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United States

Securities and Exchange Commission

Washington, D.C. 20549

FORM 10-K

(MARK ONE)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended September 30, ~~2024~~2025

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from __________ to __________

Commission File Number 001-31921

Compass Minerals International, Inc.

(Exact name of registrant as specified in its charter)


Delaware						36-3972986
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)


9900 West 109th Street,	Suite 100	66210
Overland Park,	Kansas	(Zip Code)
(Address of principal executive offices)

Registrant’s telephone number, including area code:

(913) 344-9200

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

Trading Symbol

Name of each exchange on which registered

Common stock, $0.01 par value

CMP

The New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.

Yes

☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.

Yes

☐

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing

requirements for the past 90 days.

Yes

☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

Yes

☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer

☐

Accelerated filer

Non-accelerated filer

☐

Smaller reporting company

☐

Emerging growth company

☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐


Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.			☑

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☑☐


Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).			☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Yes

☐

As of March 31, ~~2024~~2025, the aggregate market value of the registrant’s common stock held by non-affiliates of the registrant was $~~538~~318,~~071~~890,~~743~~203, based on the closing sale price of $159.7429 per share, as reported on the New York Stock Exchange.

The number of shares outstanding of the registrant’s $0.01 par value common stock at December 118, ~~2024~~2025 was 41,~~452~~819,~~793~~495 shares.

DOCUMENTS INCORPORATED BY REFERENCE

Document						Parts into which Incorporated
Portions of the Proxy Statement for the Annual Meeting of Stockholders to be held March 6, 2025						Part III, Items 10, 11, 12, 13 and 14
Certain portions of the registrant’s definitive proxy statement, in connection with its 2026 annual meeting of stockholders, to be filed within 120 days of September 30, 2025, are incorporated by reference into Part III of this Annual Report on Form 10-K.						Part III, Items 10, 11, 12, 13 and 14

Auditor Name

Auditor Location

Auditor Firm ID

KPMG LLP

Kansas City, MO

185


						COMPASS MINERALS INTERNATIONAL, INC.

TABLE OF CONTENTS

PART I		Page No.
Item 1.	Business	4
Item 1A.	Risk Factors	1314
Item 1B.	Unresolved Staff Comments	2628
Item 1C.	Cybersecurity	2628
Item 2.	Properties	2831
Item 3.	Legal Proceedings	5961
Item 4.	Mine Safety Disclosures	5962
PART II
Item 5.	Market for the Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	6164
Item 6.	Reserved	6265
Item 7.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	6366
Item 7A.	Quantitative and Qualitative Disclosures About Market Risk	7780
Item 8.	Financial Statements and Supplementary Data	7982
Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	~~127~~135
Item 9A.	Controls and Procedures	~~127~~135
Item 9B.	Other Information	~~128~~137
Item 9C.	Disclosure Regarding Foreign Jurisdictions That Prevent Inspections	~~129~~137
PART III
Item 10.	Directors, Executive Officers and Corporate Governance	~~130~~138
Item 11.	Executive Compensation	~~130~~138
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	~~130~~138
Item 13.	Certain Relationships and Related Transactions, and Director Independence	~~130~~138
Item 14.	Principal ~~Accounting~~Accountant Fees and Services	~~130~~138
PART IV
Item 15.	Exhibits, Financial Statement Schedules	~~131~~139
Item 16.	Form 10-K Summary	~~137~~144
SIGNATURES		~~138~~145

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PART I

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this Form 10-K, including without limitation our or management’s beliefs, expectations or opinions; statements regarding future events or future financial performance; our plans, objectives and strategies; our outlook, including expected sales volumes and costs; the useful life of our mine properties; conversion of mineral resources into mineral reserves; existing or potential capital expenditures, capital projects and investments; the industry and our competition; projected sources of cash flow; potential legal liability; proposed or recently enacted legislation and regulatory action; the seasonal distribution of working capital requirements; our reinvestment of foreign earnings outside the United States (“U.S.”); repatriation of foreign earnings to the U.S.; payment of future dividends and ability to reinvest in our business; our ability to optimize cash accessibility and minimize tax expense; our debt service requirements; our liquidity needs; realization of potential savings from our restructuring activities; funding obligations for our United Kingdom (“~~U.K.~~UK”) pension plan; outcomes of matters with taxing authorities; the seasonality of our business; the effects of climate change on us; and our ability to successfully remediate the material weaknesses in our internal control over financial reporting disclosed in this Form 10-K, are forward-looking statements. Forward-looking statements are those that predict or describe future events or trends and that do not relate solely to historical matters. We use words such as “may,” “would,” “could,” “should,” “will,” “likely,” “expect,” “anticipate,” “believe,” “intend,” “plan,” “forecast,” “outlook,” “project,” “estimate” and similar expressions suggesting future outcomes or events to identify forward-looking statements or forward-looking information. These statements are based on our current expectations and involve risks and uncertainties that could cause our actual results to differ materially. In evaluating these statements, you should carefully consider various risks, uncertainties and factors including, but not limited to, those listed under “Risk Factors” and elsewhere in this ~~report~~Form 10-K. Forward-looking statements are only predictions and are subject to certain risks and uncertainties that may cause our actual results to differ materially from the forward-looking statements expressed or implied in this ~~report~~Form 10-K as a result of factors, risks, and uncertainties, over many of which we do not have control.

Although we believe that the expectations reflected in the forward-looking statements are reasonable as of the date of this ~~report~~Form 10-K, we cannot guarantee future results, levels of activity, performance or achievements. We do not undertake, and hereby disclaim any obligation or duty, unless otherwise required to do so by applicable laws, to update any forward-looking statement after the date of this ~~report~~Form 10-K regardless of any new information, future events or other factors. The inclusion of any statement in this ~~report~~Form 10-K does not constitute our admission that the events or circumstances described in such statement are material to us.

Factors that could cause actual results, levels of activity, performance, or achievements to differ materially from those expressed or implied by the forward-looking statements include, but are not limited to, the following:

•risks ~~related~~relating to our mining and industrial operations;

•risks relating to unexpected or variations in geological conditions;

•risks relating to variations in weather conditions;

•our continued ability to access ambient lake brine in the Great Salt Lake;

•dependency on a limited number of key production and distribution facilities and critical equipment;

•the inability to fund necessary capital expenditures or successfully complete capital projects;

•risks and uncertainties in estimating our economically recoverable reserves and resources, our useful life of our mine properties, and our conversion of mineral resources into mineral reserves;

•~~the~~risks ~~useful~~relating ~~life~~to strikes, other forms of ~~our~~work ~~mine~~stoppage ~~properties~~or slowdown or other union activities;

•conversion of mineral resources into mineral reserves;

•strikes, other forms of work stoppage or slowdown or other union activities;

•supply constraints or price increases for energy and raw materials used in our production processes;

•our indebtedness and inability to pay our indebtedness;

•restrictions in our debt agreements that may limit our ability to operate our business or require accelerated debt payments;

•tax liabilities;

•the inability of our customers to access credit or a default by our customers of trade credit extended by us;

•financial assurance requirements;

•our payment of any dividends;

•the seasonal demand for our products;

•variables impacting effective inventory management may adversely impact our performance;

•the impact of anticipated changes in potash product prices and customer application rates;

•the impact of competition on the sales of our products;

•inflation ~~risks~~could result in higher costs and decreased profitability;

•the impact of increasing costs or a lack of availability of transportation services;

•risks associated with our international operations and sales, including changes in currency exchange rates;

•conditions in the sectors where we sell products and supply and demand imbalances for competing products;

•our ~~rights~~indebtedness and ~~governmental~~inability ~~authorizations~~ to ~~mine~~pay ~~and operate~~ our ~~properties~~indebtedness;

2•restrictions ~~2024~~in ~~FORM~~our ~~10-K~~debt agreements that may limit our ability to operate our business, incur additional debt, pay dividends, refinance debt and to do so at favorable terms, and may require accelerated debt payment;

•exposure to tax liabilities could adversely impact our profitability, cash flow, and liquidity;

•the inability of our customers to access credit or a default by our customers of trade credit extended by us;


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•~~risks~~our ~~related~~ability to ~~unanticipated~~satisfy ~~litigation~~financial orassurance ~~investigations or pending litigation or investigations or other contingencies~~requirements;

•the payment of any future cash dividends;

•our rights and governmental authorizations to mine and operate our properties;

•risks relating to unanticipated litigation or investigations or pending litigation or investigations or other contingencies;

•compliance with environmental, health and safety laws and regulations;

•risks relating to environmental liabilities;

•compliance with foreign and U.S. laws and regulations related to import and export requirements and anti-corruption laws;

•changes in laws, industry standards and regulatory requirements;

•risks relating to product liability claims and product recalls;

•misappropriation or infringement claims relating to intellectual property;

•inability to obtain required product registrations or increased regulatory requirements;

•our ability to successfully implement our strategies;

•risks ~~related~~relating to labor shortages and the loss of key personnel;

•a compromise of our computer systems, information technology or operations technology or the inability to protect confidential or proprietary data;

•the effects of climate change and related laws and regulations;

•our ability to expand our business through acquisitions and investments, realize anticipated benefits from acquisitions and investments and integrate acquired businesses;

•outbreaks of contagious disease or similar public health threats;

•domestic and international general business, economic, political, regulatory, social and ~~economic~~financial market conditions;

•our ability to successfully remediate the material weaknesses in internal control over financial reporting disclosed in this Form 10-K; and

•other ~~risk~~risks ~~factors~~and uncertainties included in this ~~report~~Form 10-K or reported from time to time in our filings with the Securities and Exchange Commission (the “SEC”). ~~See “Where You Can Find More Information.”~~

MARKET AND INDUSTRY DATA AND FORECASTS

This ~~report~~Form 10-K includes market share and industry data and forecasts that we obtained from publicly available information and industry publications, surveys, market research, internal company surveys and consultant surveys. Industry publications and surveys, consultant surveys and forecasts generally state that the information contained therein has been obtained from sources believed to be reliable, but there can be no assurance as to the accuracy and completeness of such information. We have not independently verified any of the data from third-party sources nor have we ascertained the underlying economic assumptions relied upon therein. Similarly, internal company surveys, industry forecasts and market research, which we believe to be reliable based upon management’s knowledge of the industry, have not been verified by any independent sources. Except where otherwise noted, references to North America include only the continental U.S. and Canada, references to the ~~U.K.~~UK, include only England, Scotland and Wales, and statements as to our position relative to our competitors or as to market share refer to the most recent available data. Statements concerning (a) North American consumer and industrial salt and highway deicing salt markets are generally based on historical sales volumes, (b) ~~U.K.~~UK highway deicing salt sales are generally based on historical sales volumes, and (c) sulfate of potash are generally based on historical sales volumes. Except where otherwise noted, all references to tons refer to “short tons” and all amounts are in U.S. dollars. One short ton equals 2,000 pounds and one metric ton equals 2,204.6 pounds.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy, and other information with the SEC and our SEC filings are available at the SEC’s website at www.sec.gov. Copies of these documents are also available free of charge on our website, www.compassminerals.com. We also use our website as a tool to disclose important information about the company and comply with our disclosure obligations under Regulation Fair Disclosure. The information on our website (or any webpages referenced in this Form 10-K) is not part of this or any other report we file with, or furnish to, the SEC. Further, our references to website URLs are intended to be inactive textual references only.

You may also request a copy of any of our filings, at no cost, by writing or telephoning:

Investor Relations

Compass Minerals International, Inc.

9900 West 109th Street, Suite 100

Overland Park, Kansas 66210

~~For~~3 ~~general~~2025 ~~inquiries~~FORM ~~concerning us, please call (913) 344~~10-~~9200.~~K

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~~Unless~~For ~~the~~general ~~context~~inquiries ~~requires~~concerning ~~otherwise, references in this report to the “Company,” “Compass Minerals,” “CMP,” “we,” “~~us~~” and “our” refer to Compass Minerals International~~, ~~Inc.~~please ~~(“CMI,”~~call ~~the parent holding company~~(913) ~~and its consolidated subsidiaries collectively~~344-9200.

Unless the context requires otherwise, references in this Form 10-K to the “Company,” “Compass Minerals,” “CMP,” “we,” “us” and “our” refer to Compass Minerals International, Inc. (“CMI,” the parent holding company) and its consolidated subsidiaries collectively.

ITEM 1. BUSINESS

~~COMPANY~~General ~~OVERVIEW~~Development Of Business

Compass Minerals International, Inc. through its subsidiaries is a leading provider of essential minerals, ~~focused~~primarily onsalt ~~safely delivering where~~ and ~~when~~plant ~~it matters to help solve nature’s challenges for customers and communities~~nutrition. Our ~~salt~~production ~~products~~sites ~~help keep roadways safe during winter weather and~~ are ~~used~~located in ~~numerous~~the ~~other~~United ~~consumer,~~States ~~industrial~~(“U.S.”), ~~chemical~~Canada and ~~agricultural applications. Our plant nutrition products help improve~~ the ~~quality~~United ~~and~~Kingdom ~~yield of crops, while supporting sustainable agriculture~~(“UK”). WeThe ~~are~~Company also ~~working~~provides torecords ~~develop~~management ~~long-term~~services ~~fire-retardant~~in ~~solutions to help combat wildfires. As of September 30, 2024, we operate 12 production and packaging facilities with nearly 1,900 employees throughout~~ the UUK.~~S., Canada and the U.K., including:~~

Back-to-Basics Strategy

Our back-to-basics strategy focuses on improving cash flow generation and returns on capital in our core Salt and Plant Nutrition businesses through cost management and appropriate flexibility in capital intensity. We are committed to continually balancing inventory volumes, improving our cost structure, and enhancing profitability, leveraging our unique assets with durable competitive advantages and strong leadership positions in our respective marketplaces. We believe this strategy will enable us to create meaningful, long-term shareholder value and strengthen our financial performance.

To achieve the strategy of improving cash flow generation and returns on capital in the core Salt and Plant Nutrition businesses, we have taken the following specific actions:

•Cost management. Implementing cost control measures to reduce expenses and to improve our cost structure and profitability.

•Debt reduction. Reducing levels of indebtedness to create long-term shareholder value.

•Continually balancing inventory volumes. Optimizing inventory volumes and associated cash impacts, while ensuring market opportunities are met.

•Flexibility in capital intensity. Optimizing our capital expenditures to enhance cash flow and returns on capital.

The following are key actions we took on our back-to-basics strategy to strengthen our financial performance for the fiscal year ended September 30, 2025.

•Exited the Fire Retardant Business. On March 25, 2025, we announced actions to further optimize the cost structure of the Company and focus on activities in our core Salt and Plant Nutrition businesses. As a result, we began the process of exiting the Fortress North America, LLC (“Fortress”) fire retardant business and terminated the employment of all Fortress employees. On May 30, 2025, we entered into an Asset Purchase Agreement and sold substantially all Fortress assets. See Part II, Item 8, Note 1. Organization and Formation and Note 2. Summary of Significant Accounting Policies of our Consolidated Financial Statements for further information.

•Selling, General, and Administrative Cost Reduction. Selling, general, and administrative (“SG&A”) expenses decreased 17.8%, or $24.5 million, during the fiscal year ended September 30, 2025, compared to the fiscal year ended September 30, 2024, primarily due to reductions in corporate compensation expense and professional services.

•Refinancing Transaction. On June 16, 2025, we issued $650.0 million aggregate principal amount of our 8.00% Senior Notes due 2030 (the “2030 Notes”). We used the net proceeds from the 2030 Notes to (i) repay all outstanding amounts under our senior secured credit facility, including $43.5 million under our revolving credit facility and $191.3 million under our term loan and (ii) redeem approximately $350.0 million of our outstanding 6.75% Senior Notes due 2027 at a redemption price of 101.125% of the principal amount, plus accrued and unpaid interest. For further information, see Part II, Item 8, Note 10. Long Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements.

•Continually Balancing Inventory Volumes. Throughout the fiscal year ended September 30, 2025, we realized a working capital release of nearly $117 million out of finished goods inventory. See Part II, Item 8, Note 5. Inventories of our Consolidated Financial Statements for further details of our inventory balances.


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•Capital Expenditure Reduction. Capital expenditures decreased 39.0%, or $44.5 million, during the fiscal year ended September 30, 2025, compared to fiscal year ended September 30, 2024.

•Dividends. The Board of Directors did not declare dividends, and does not expect to declare dividends for the foreseeable future in order to align the Company’s capital allocation priorities with its corporate focus on accelerating cash flow generation and debt reduction.

Please see Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and Note 5. Inventories and Note 10. Long Term Debt and Finance Lease Liabilities under Part II. Item 8 of this Form 10-K for additional information.

Description Of Business

Compass Minerals is a leading provider of essential minerals focused on safely delivering where and when it matters to help solve nature’s challenges for customers and communities. Our salt products help keep roadways safe during winter weather and are used in numerous other consumer, industrial, chemical and agricultural applications. Our plant nutrition products help improve the quality and yield of crops, while supporting sustainable agriculture. As of September 30, 2025, we operate 12 production and packaging facilities with more than 1,800 employees throughout the U.S., Canada and the UK, including:

•The largest underground rock salt mine in the world in Goderich, Ontario, Canada;

•The largest dedicated rock salt mine in the ~~U.K.~~UK in Winsford, Cheshire;

•A solar evaporation facility located near Ogden, Utah, which is both the largest sulfate of potash specialty fertilizer (“SOP”) production site and the largest solar salt production site in the Western Hemisphere; and

•Several mechanical evaporation facilities producing consumer and industrial salt.

See Item 2, “Properties,” for a discussion of our mining properties, including processing methods, facilities, production and summaries of our mineral resources and reserves, both in the aggregate and for our individual material mining properties.

Our ~~Salt~~business ~~segment~~is ~~provides~~operated ~~highway~~in ~~deicing~~two ~~salt~~reportable tosegments, ~~customers~~Salt ~~in North America~~ and ~~the~~Plant UNutrition.K. asThe ~~well~~results asof ~~consumer~~operations ~~deicing~~for ~~and~~the ~~water~~Company’s ~~conditioning~~exited ~~products,~~fire ~~ingredients~~retardant ~~used~~business, inrecords ~~consumer~~management ~~and~~business, ~~commercial food preparation~~ and other ~~salt-based~~incidental ~~products~~revenues ~~for~~are ~~consumer,~~included ~~industrial,~~in ~~chemical~~Corporate and ~~agricultural~~Other ~~applications~~and inare ~~North~~not ~~America.~~material Into ~~the U.K., we operate a records management business utilizing excavated areas of~~ our ~~Winsford~~consolidated ~~salt~~financial ~~mine with one other location in London, England~~results.

Our Salt segment provides highway deicing salt to customers in North America and the UK as well as consumer deicing and water conditioning products, ingredients used in consumer and commercial food preparation and other salt-based products for consumer, industrial, chemical and agricultural applications in North America. In the UK, we operate a records management business utilizing excavated areas of our Winsford salt mine with one other location in London, England.

Our Plant Nutrition segment produces and markets SOP products in various grades domestically and internationally to distributors and retailers of crop inputs, as well as growers and for industrial uses. We market our SOP under the trade name Protassium+®.

InWe ~~May~~sell ~~2023,~~our wesalt ~~completed~~and ~~the~~plant ~~purchase~~nutrition ofproducts ~~Fortress~~primarily ~~North~~in ~~America~~the U.S., ~~LLC~~Canada ~~(“Fortress”),~~and athe ~~fire~~UK. ~~retardant~~See ~~company~~Part ~~working~~II, toItem ~~develop~~8, ~~long-term~~Note ~~fire~~12. ~~retardant~~Operating ~~solutions~~Segments to ~~help~~our ~~combat~~Consolidated ~~wildfires~~Financial ~~(see~~Statements ~~Part~~for ~~II,~~financial ~~Item~~information 8,relating ~~Note~~to ~~3 of~~ our ~~Consolidated~~operations ~~Financial~~by ~~Statements)~~geographic areas.

We sell our salt, plant nutrition and fire retardant products primarily in the U.S., Canada and the U.K. See Part II, Item 8, Note 14 to our Consolidated Financial Statements for financial information relating to our operations by geographic areas.

On February 16, 2021, we announced our plan to restructure our former Plant Nutrition South America segment to enable targeted and separate sales processes for each portion of the former segment, including our chemicals and specialty plant nutrition businesses along with our equity method investment in Fermavi Eletroquímica Ltda. (“Fermavi”). On March 16, 2021, our Board of Directors approved a plan to sell our South America chemicals and specialty plant nutrition businesses, our investment in Fermavi and our North America micronutrient product business (collectively, the “Specialty Businesses”) as described further in Part II, Item 8, Note 1 and Note 4 to our Consolidated Financial Statements. Consequently, the Specialty Businesses qualified for presentation as discontinued operations in accordance with U.S. generally accepted accounting principles (“GAAP”). Accordingly, the Specialty Businesses’ results of operations are presented as discontinued operations in the Consolidated Statements of Operations for the fiscal year ended September 30, 2022. As a result, we are presenting two reportable segments in continuing operations, Salt and Plant Nutrition in this Form 10-K. See Part II, Item 8, Note 14 to our Consolidated Financial Statements for more information.

SALT SEGMENT

Overview

Salt is indispensable and enormously versatile with thousands of reported uses. In addition, there are no known cost-effective alternatives for most high-volume uses. Through the use of effective mining techniques and efficient production processes, we leverage our high-grade salt deposits, which are among the most extensive in the world. Further, many of our Salt segment assets are in locations that are logistically favorable to our core markets. Our strategy for this segment is to focus on driving profitability from every ton we produce through cost efficiency as well as commercial and operational execution.

Through our Salt segment, we produce, market and sell salt (sodium chloride) and magnesium chloride in North America and sodium chloride in the UUK.K. Our Salt products include rock salt, mechanically-evaporated salt, solar-evaporated salt, brine magnesium chloride and flake magnesium chloride. We also purchase potassium chloride (“KCl”) and calcium chloride to sell as finished products or to blend with sodium chloride to produce specialty products. Sodium chloride represents the vast

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majority of the products we produce, market and sell. InFor the fiscal years ended September 30, 2025, September 30, 2024, and September 30, 2023, the Salt segment sales as a percentage of total sales accounted for approximately 82%, 81%, and 84%, respectively, of our sales (see Part II, Item 8, Note 1412. toOperating Segments of our Consolidated Financial Statements for segment financial information).

Salt segment sales as a percentage of total sales from continuing operations for the fiscal years ended September 30, 2024, 2023 and 2022, are as follows:

Our Salt segment products are used in a wide variety of applications, including as a deicer for roadways, consumer and professional use, as an ingredient in chemical production, for water treatment, human and animal nutrition and for a variety of other consumer and industrial uses.

Historical demand for salt has remained relatively stable during periods of rising prices and through a variety of economic cycles due to its relatively low cost and diverse number of end uses. As a result, our cash flows from our Salt segment are not materially impacted by economic cycles. However, demand for deicing salt products is primarily affected by the number and intensity of snow events and temperatures in our service territories and fluctuations have impacted, and may impact, our cash flows. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Seasonality” for more information on the seasonality of our Salt segment results.

Salt Industry Overview

In our primary markets, we estimate that the consumption of highway deicing rock salt in North America, including rock salt used in chemical manufacturing processes, is approximately 39 million tons per year, assuming average winter weather conditions~~, while the consumer and industrial market is approximately 10 million tons per year~~. In the ~~U.K.~~UK, we estimate that the consumption of highway deicing salt is approximately 2 million tons per year, assuming average winter weather conditions. We also estimate that salt consumption in the U.S. has increased at a long-term historical average rate of flat to approximately 1% per year, although there have been recent fluctuations above and below this average driven primarily by winter weather variability.

Salt prices vary according to purity, end use and variations in refining and packaging processes. Management estimates that salt prices in the U.S. have increased at a long-term historical average rate of approximately 3% to 4% per year, although there have been recent fluctuations above and below this average. Due to salt’s relatively low production cost, transportation and handling costs tend to be a significant component of the total delivered cost, which makes logistics management and customer service key competitive factors in the industry. The high relative cost associated with transportation of salt tends to favor producers located nearest to customers.

Products and Sales

We sell our Salt segment products through our highway deicing product line (which includes brine magnesium chloride as well as rock salt treated with this mineral) and our consumer and industrial product line (which includes salt as well as products containing magnesium chloride and calcium chloride in both pure form and blended with salt).

Highway deicing, including salt sold to chemical customers, constituted 6063% of our fiscal ~~2024~~2025 Salt segment sales. Our principal customers are states, provinces, counties, municipalities and road maintenance contractors that purchase bulk deicing salt, both treated and untreated, for ice control on public roadways. Highway deicing salt in North America is sold primarily through an annual tendered bid contract process with governmental entities, as well as through multi-year contracts,. ~~with price~~Price, product quality and delivery capabilities asare the primary competitive market factors. Some sales also occur through negotiated sales contracts with customers, particularly in the UUK.K. Since transportation costs are a relatively large portion of the delivered cost of our products to customers, locations of salt sources and distribution networks also play a significant role in the ability of suppliers to cost-effectively serve customers. We have an extensive network of approximately 80 depots for storage and distribution of highway deicing salt in North America. The majority of these depots are located on the Great Lakes and the Mississippi River and Ohio River systems. Deicing salt product from our Ogden facility supplies customers in the Western and upper Midwest regions of the U.S. Treated rock salt, which is typically rock salt with brine magnesium chloride and organic materials that enhance the salt’s performance, is sold throughout our markets.

5We ~~2024~~believe ~~FORM~~our 10production capability at our Winsford mine and favorable logistics position enhance our ability to meet the UK’s winter demands. Due to our strong position, we are viewed as a key supplier by the UK’s Highways Agency. In the UK, approximately 75% of our highway deicing customers have multi-Kyear contracts.


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~~upper~~of ~~Midwest~~our ~~regions~~North ofAmerican deicing sales are made in Canada and the Midwestern U.S. ~~Treated~~ ~~rock~~where ~~salt,~~inclement ~~which~~weather isduring ~~typically~~the ~~rock~~winter ~~salt~~months causes dangerous road conditions. In keeping with ~~magnesium~~industry ~~chloride~~practice, ~~brine~~we ~~and~~stockpile ~~organic~~salt ~~materials~~to ~~that~~meet ~~enhance~~estimated requirements for the ~~salt~~next winter season. See “Management’s ~~performance,~~Discussion isand ~~sold~~Analysis ~~throughout~~of Financial Condition and Results of Operations—Seasonality” for more information on the seasonality of our ~~markets~~Salt segment results.

We believe our production capability at our Winsford mine and favorable logistics position enhance our ability to meet the U.K.’s winter demands. Due to our strong position, we are viewed as a key supplier by the U.K.’s Highways Agency. In the U.K., approximately 75% of our highway deicing customers have multi-year contracts.

Winter weather variability is the most significant factor affecting salt sales for deicing applications because mild winters reduce the need for salt used in ice and snow control. On average, over the last three years, approximately two-thirds of our deicing product sales occurred during the North American and European winter months of November through March. The vast majority of our North American deicing sales are made in Canada and the Midwestern U.S. where inclement weather during the winter months causes dangerous road conditions. In keeping with industry practice, we stockpile salt to meet estimated requirements for the next winter season. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Seasonality” for more information on the seasonality of our Salt segment results.

Our principal chemical customers are producers of intermediate chemical products used in the production of vinyls and other chemicals, pulp and paper, as well as water treatment and a variety of other industrial uses. We typically have multi-year supply agreements with these customers. Price, service, product quality and security of supply are the major competitive market factors.

Sales of our consumer and industrial products accounted for 4037% of our fiscal ~~2024~~2025 Salt segment sales. We are the third largest producer of consumer and industrial salt products in North America. These products include commercial and consumer applications, such as water conditioning, consumer and professional ice control, food processing, agricultural applications, table salt and a variety of industrial applications. We estimate we are among the largest private-label producers of water conditioning salt in North America and of table salt in Canada. Our Sifto brand encompasses a full line of salt products, which are well recognized in Canada.

Our consumer and industrial ~~business~~products ~~has~~include ~~broad product lines with~~ both private-label and Company brands. Our consumer and industrial product line is distributed through many channels, including retail, agricultural, industrial, janitorial and sanitation, and resellers. These consumer and industrial products are channeled from our plants and third-party warehouses to our customers using a combination of direct sales personnel, contract personnel and a network of brokers or manufacturers’ representatives.

The chart below shows our annual sales volumes of Salt segment products for the fiscal years ended September 30, ~~2024~~2025, ~~2023~~September 30, 2024, and ~~2022~~September 30, 2023:

Competition

We face strong competition in each of the markets in which we operate. In North America, other large, nationally and internationally recognized companies compete with our Salt segment products. In addition, there are also several smaller regional producers of salt. There are several importers of salt into North America, which mostly impact the East Coast and West Coast of ~~the~~North ~~U.S.~~America, where we have minimal market presence. Two competitors serve the highway deicing salt market in the ~~U.K.~~UK, one in Northern England and one in Northern Ireland. Typically, there are not significant imports of highway deicing salt into the UUK.K.

Salt is a commodity, which limits the potential for product differentiation and increases competition. Additionally, low barriers to entry in the consumer and industrial markets increase competition. Our advantageous geographical locations, superior assets, including the scale and deep-water port associated with our Goderich Mine, complimented by our distribution network, strengthen our competitive position.

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PLANT NUTRITION SEGMENT

Industry Overview

Fertilizers are critical for efficient crop production using the limited arable land resources available around the world. The nutrients needed to ensure plant health can be divided into three categories:

•macro nutrients - the traditional NPK fertilizers (nitrogen (N), phosphorus (P) and potassium (K));

•secondary nutrients - calcium, magnesium and sulfur; and

•specialty plant nutrients - trace elements of iron, manganese, copper, boron, zinc, molybdenum, chlorine and nickel.

Factors influencing the plant nutrition market include world grain and food supply, currency fluctuations, weather and climate change, grower incomes, changes in consumer diets, general levels of economic activity, government food programs, governmental agriculture and energy policies in the U.S. and around the world, and the amount or type of crop grown in certain locations, or the type or amount of fertilizer product used. In addition, our Plant Nutrition segment results can be impacted by seasonality (see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Seasonality” for more information).

Our Plant Nutrition segment currently generates nearly all of its sales and earnings through the production and sale of SOP. There are two major forms of potassium-based fertilizer, SOP, a specialty form of potassium which also provides plant-ready sulfur, and muriate of potash (“MOP” or “KCl”). Based on data from Green Markets® A Bloomberg Company, management estimates the average annual worldwide consumption of all potash fertilizers is approximately 81 million tons, with MOP accounting for approximately 8788% of all potash used in fertilizer production. SOP represents approximately 109% of all potash production. The remainder of potash is supplied in forms containing varying concentrations of potassium (expressed as potassium oxide) along with different combinations of co-nutrients. SOP, which contains the equivalent of approximately 50% potassium oxide, maintains a price premium over MOP due to the fact that it contains the secondary nutrient, sulfur, does not contain chlorides and is more expensive to produce than MOP. Additionally, many high-value or chloride-sensitive crops experience improved yields and quality when SOP is applied instead of MOP. SOP is also a more cost-effective alternative to other forms of specialty potash.

Our SOP sales are primarily concentrated in the Western and Southeastern U.S. where the crops and soil conditions favor the use of low-chloride potassium nutrients. Consequently, weather patterns and field conditions in these locations can impact Plant Nutrition sales volumes.

While long-term global consumption of potash has increased in response to growing populations and the need for additional food supplies, the market for commodity potash has been challenged in recent years due to downturns in the broader crop market which pressure grower incomes. Additionally, demand for our SOP products has been resilient despite the challenges facing the global potash market.

We expect the long-term demand for potassium nutrients to continue to grow as arable land per capita decreases, thereby encouraging improved crop yield efficiencies. We expect our future growth to stem from the conversion of certain commodity potassium applications into higher yield SOP applications.

Approximately 9288% of our Plant Nutrition segment sales in fiscal ~~2024~~2025 were made to U.S. customers, who include retail fertilizer dealers and distributors of agricultural products as well as professional turf care customers. In some cases, these dealers and distributors combine or blend our Plant Nutrition segment products with other fertilizers and minerals to produce fertilizer blends tailored to individual requirements.

Products and Sales

We currently generate nearly all of our sales and earnings in our Plant Nutrition segment through the production and sale of SOP. Our SOP is sold in various grades under our Protassium+ brand. Our Protassium+ product line consists of different grades sized for use in broadcast spreaders, direct application and liquid fertilizer solutions. Our turf product line consists of grades sized for use by the turf and ornamental markets and for blends used on golf course greens. We also provide a product line suitable for organic cropping systems with grades sized for a wide range of applications.

~~Our~~8 ~~Protassium+~~2025 ~~product~~FORM line is generally sold to crop input distributors and dealers who may blend our products with other fertilizer products to sell to farmers and growers, or it may be sold as the final product. Our commercial efforts focus on educating and selling the agronomic benefits of SOP as a source of potassium nutrients.10-K

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Our Protassium+ product line is generally sold to crop input distributors and dealers who may blend our products with other fertilizer products to sell to farmers and growers, or it may be sold as the final product. Our commercial efforts focus on educating and selling the agronomic benefits of SOP as a source of potassium nutrients.

Competition

SOP is marketed globally; based on our latest information, approximately 5562% of the world’s ~~10.7 million~~ tons of estimated capacity is located in China. Management estimates global SOP capacity to be as follows:

Source: Green Markets ® A Bloomberg Company

We are the leading SOP producer and marketer in North America and we also market SOP products internationally, depending on market conditions. Our major competition for SOP sales in North America includes imports from the European Union. Fluctuations in the values of foreign currencies in relation to the U.S. dollar, coupled with Baltic freight rates impact the level of international competition we face. As the only SOP producer with production facilities in North America, and as a result of our logistically favorable production site near Ogden, Utah, we estimate that our share of the North American market is sizable. In addition to imported SOP, there is functional competition between SOP and other forms of potassium crop nutrients, such as MOP. The specialty plant nutrient market is highly fragmented. because ~~Commodity~~commodity and specialty crops require specialty plant nutrients in varying degrees depending on the crop and soil conditions.

OTHER BUSINESSES

~~Fortress~~DeepStore is our ~~fire~~records ~~retardant~~management ~~company~~business ~~working~~in tothe ~~develop~~UK ~~long-term~~that ~~aerial~~utilizes portions of previously excavated space in our salt mine in Winsford, Cheshire, and ~~ground-applied~~one ~~fire~~warehouse ~~retardant~~location ~~products~~in toLondon, ~~help~~England ~~prevent~~for secure underground document and ~~combat~~archive ~~wildfires~~storage. Currently, DeepStore does not have a significant share of the document storage market in the UK, and it is not material to our consolidated financial statements.

Prior to May 30, 2025, Fortress was our fire retardant business, which worked to develop long-term aerial and ground-applied fire retardant products to help prevent and combat wildfire. The fire retardant revenue generated in the U.S. was not material to our consolidated financial statements. Fortress had one primary customer, the U.S. Forest Service (“USFS”), for the 2023 fire season. Fortress did not secure a contract for the 2024 fire season. AsOn ofMarch ~~the~~25, ~~date~~2025, ofwe ~~this~~announced ~~report,~~actions weto ~~have~~further ~~generated~~optimize ~~all~~the cost structure of the Company and focus on our ~~fire~~core ~~retardant~~Salt ~~revenue~~and inPlant ~~the~~Nutrition Ubusinesses.S. ~~and~~On itMay is30, ~~not~~2025, ~~material~~we inentered ~~comparison~~into toan ~~our~~Asset ~~Salt~~Purchase ~~and~~Agreement, ~~Plant~~selling ~~Nutrition~~substantially ~~segments~~all Fortress assets.

DeepStore is our records management business in the U.K. that utilizes portions of previously excavated space in our salt mine in Winsford, Cheshire, for secure underground document and archive storage and one warehouse location in London, England. Currently, DeepStore does not have a significant share of the document storage market in the U.K., and it is not material in comparison to our Salt and Plant Nutrition segments.

INTELLECTUAL PROPERTY

To protect our intellectual property, we rely on a combination of approaches, including but not limited to, patents, trademarks, copyrights, trade secret protection, employee and third-party non-disclosure agreements, license arrangements and domain name registrations. These protections are important to our business and we believe that our success is at least partly dependent on the acquisition and maintenance of these rights. However, we rely primarily on the innovative skills, technical competence, operational knowledge and marketing abilities required by our business in order to succeed.

We9 ~~sell~~2025 ~~many~~FORM of our products under a number of registered trademarks that we believe are widely recognized in the industry. Our trademarks registered pursuant to applicable intellectual property laws include, but are not limited to, COMPASS MINERALS, AMERICAN STOCKMAN, CANADIAN STOCKMAN, DUSTGARD, FREEZGARD, ICEAWAY, PROSOFT, SAFE STEP, SAFE STEP PRO, SIFTO, SURESOFT, SURE PAWS and PROTASSIUM+ and FORTRESS FIRE RETARDANT SYSTEMS. 10-K

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~~Competitors~~on ~~may~~the ~~challenge~~acquisition ~~our~~and ~~patent~~maintenance ~~rights~~of orthese ~~assert alleged claims regarding infringement~~rights. IfHowever, ~~our~~we ~~patents~~rely ~~are~~primarily ~~held~~on ~~invalid~~the orinnovative ~~unenforceable~~skills, ~~our~~technical ~~competitors~~competence, ~~could~~operational ~~commercialize~~knowledge ~~our~~and ~~patented~~marketing ~~technology.~~abilities Ifrequired ~~it is determined~~ by aour ~~court~~business ofin ~~competent~~order ~~jurisdiction that we have infringed another party’s patent, we may not be able~~ to ~~use or sell that technology~~succeed.

We sell many of our products under a number of registered trademarks that we believe are widely recognized in the industry. Our trademarks registered pursuant to applicable intellectual property laws include, but are not limited to, COMPASS MINERALS, AMERICAN STOCKMAN, CANADIAN STOCKMAN, DUSTGARD, FREEZGARD, ICEAWAY, PROSOFT, SAFE STEP, SAFE STEP PRO, SIFTO, SURESOFT, SURE PAWS and PROTASSIUM+.

Any issued patents, trademarks or copyrights on our proprietary technology may not provide us with substantial protection or be commercially beneficial to us. The issuance of a patent is not conclusive as to its validity or its enforceability. Competitors may challenge our patent rights or assert alleged claims regarding infringement. If our patents are held invalid or unenforceable, our competitors could commercialize our patented technology. If it is determined by a court of competent jurisdiction that we have infringed another party’s patent, we may not be able to use or sell that technology.

With respect to proprietary know-how, we rely on trade secret protection and confidentiality agreements. Monitoring the unauthorized use of our technology is difficult, and we may not be able to prevent unauthorized use of our technology. The disclosure or misappropriation of our intellectual property could harm our ability to protect our rights and our competitive position (see “Risk Factors—Our intellectual property may be misappropriated or subject to claims of infringement” for more information).

HUMAN CAPITAL MANAGEMENT

As of September 30, ~~2024~~2025, we employed 1,~~894~~849 employees, of which ~~986~~906 were located in the U.S., ~~721~~761 were located in Canada, and ~~187~~182 were located in the UUK.K. Nearly 50% of our workforce is represented by collective bargaining agreements (“CBA”). Of our 12 ~~collective~~CBAs ~~bargaining agreements~~ in effect on September 30, ~~2024, six will expire in fiscal~~ 2025: ~~(including our Cote Blanche mine), four will expire in fiscal 2026 (including our Goderich mine), and two will expire in fiscal 2027.~~

•Six expired in fiscal 2025 (including our Cote Blanche mine), four of which were renewed/renegotiated and two are still in the process of being negotiated;

•Four will expire in fiscal 2026 (including our Goderich mine, which have 393 positions represented by a CBA); and

•Two will expire in fiscal 2027.

We believe that our workforce drives the success of our Company and is paramount to creating long-term value. We strive to put our employees first and foster an environment in which their safety, well-being, career progression and sense of belonging are prioritized. By investing in our workforce and culture, we are helping to ensure a strong, sustainable future for our Company.

To help maintain a focus on our workforce and culture, as well as measure our progress in these areas, we announced in fiscal 2022 a set of fiscal 2025 environmental, social and governance goals and targets, including in the categories of safety, employee development, and diversity and inclusion.

Environmental, Health and Safety

At Compass Minerals, we prioritize a safe and healthy work environment for all our employees. We are focused on the ultimate goal of zero harm, which includes zero injuries to our employees and contractors, and zero environmental incidents. This goal requires the collaboration and participation of all employees, at every site. We measure zero harm by how we are decreasing our total recordable injury rate (“TRIR”) and improving our environmental compliance-based metrics. For the fiscal year ended September 30, ~~2024~~2025, our TRIR is 1.285. Our reporting standard, TRIR, is a stringent incident reporting standard based upon the U.S. Department of Labor’s Mine Safety and Health Administration regulations. The standard includes all medical treatment, lost time and restricted-duty injuries based upon 200,000 exposure hours to enable increased reporting consistency across our organization and provides greater clarity of operational safety performance and capabilities.

AWe key driver of this trajectory has been the implementation of the SafeStart® methodology across our organization. Tools introduced through SafeStart training addressed unintentional human error and critical safety habits, which reduce risk and the probability of injury. Additionally, we approach health and safety through the lens of continuous improvement and utilize an environmental, health and safety framework that includes policies, procedures, training and Company standards that go beyond compliance. Each of our ~~operational~~ sites ~~has~~have a safety committee, which includes employees and management, and when applicable, union representation. In ~~addition~~fiscal 2025, ~~our sites form~~ focus groups were formed to ~~engage~~re-evaluate ~~team~~our ~~members~~top risks, review policies and ~~establish~~create ~~best~~the ~~practices~~framework ~~for~~to ~~specific~~introduce ~~health~~standardized ~~and~~fatal ~~safety~~risk ~~issues~~management tools in fiscal 2026. To keep health and safety top of mind throughout the year, we encourage our employees to begin internal meetings with a “safety ~~share,” a safety~~ reminder or a lesson learned, known as a “safety share.”

~~Organizational~~10 ~~Health~~2025 FORM 10-K

In fiscal 2024, our journey to improve organizational health continued to involve ensuring that our workforce is engaged, supported and equipped to support the needs of our customers and communities. One area of focus in fiscal 2024 included an enterprise-wide, CEO-led discussion about the importance of living our Core Values and demonstrating Integrity, Respect, Collaboration, Value Creation and High Performance in every interaction.

Diversity, Belonging, Inclusion and Equity

At Compass Minerals, we believe that everyone has a voice and every voice matters. We hire, promote and retain people with different backgrounds and experiences, which strengthens our culture and brings a wider range of perspectives to help solve critical issues. Our diversity, belonging, inclusion and equity (“DBIE”) approach focuses on raising awareness and educating employees, engaging employees in initiatives to create a sense of belonging, and finally, having a positive impact on our organization and in our communities by partnering with external groups working to improve DBIE.

In fiscal 2024, we maintained and continued to grow our six employee resource groups (“ERGs”): Black Employees and Allies, Emerging Leaders, Compass Pride for LGBTQ+ employees and allies, Women and Allies, Advanced Career for seasoned employees and allies and Asian Employees and Allies. To further support the importance of inclusion and belonging, we celebrated International Allyship Day at all locations in fiscal 2024. On this day, we came together to recognize the

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~~importance~~Employee ofInclusion ~~standing up for one another~~ and ~~building bridges of support and understanding. In addition, we continue to focus on strategies to diversify our talent pipeline and to ensure our internal processes are inclusive.~~ Belonging

We believe that every voice matters and we are dedicated to creating a work environment where each employee feels valued, represented and encouraged. We are guided by our Core Values and are committed to creating a safe and inclusive organization where all are treated with dignity. We are focused on hiring, promoting and retaining exceptional talent and seek to attract individuals with a broad range of backgrounds and experiences, which strengthens our culture and brings a wider range of perspectives to help solve critical issues. To promote inclusion, belonging and alignment with our culture, we support our employee resource groups, which are each accessible to all employees and offer opportunities for mentoring, development and engagement while also helping to drive business results.

Employee Development

In fiscal ~~2024~~2025, we continued ~~utilizing~~to provide Compass Minerals University (“CMU”), an online platform for employee training and development. CMU provides our employees with on‑demand access to more than 500 learning modules on topics ranging from project management to strategic thinking to emotional intelligence. ~~Content~~We isalso ~~presented~~developed inand alaunched ~~variety~~training ofthis ~~formats~~year ~~from~~for ~~videos~~frontline ~~and~~supervisors, ~~readings~~covering totopics ~~downloadable~~such ~~templates~~as ~~and~~training ~~work~~on ~~aids~~performance ~~for~~mindset, ~~managers~~team toeffectiveness ~~use~~and incommunication ~~team~~styles. ~~meetings~~Additionally, orwe ~~with~~make ~~direct~~programs ~~reports.~~available Inthrough ~~addition,~~our ~~there~~employee ~~are~~resource ~~live~~groups ~~virtual~~that ~~trainings~~provide ~~our~~development opportunities to help employees ~~can~~increase ~~attend~~their knowledge and grow professionally.

WeAdditionally, employees have ~~other~~opportunities ~~forms~~for ofprofessional development ~~opportunities~~through ~~for~~strategic ~~employees,~~partnerships with several outside organizations such as ~~training~~Central onExchange, ~~performance~~Women ~~mindset~~in Mining, ~~team~~Society ~~effectiveness~~of ~~and~~Women ~~communication styles~~Engineers, and ~~programs~~American ~~available~~Royal, ~~through~~as ~~our~~well ~~ERGs.~~as ~~Several~~through ~~options~~membership ~~are~~in ~~available~~trade togroups, ~~employees~~including ~~who~~The ~~are~~Fertilizer ~~looking~~Institute, toUK ~~increase~~Salt ~~their~~Association ~~knowledge~~ and ~~grow~~Ontario ~~professionally.~~Mining Association.

Additionally, employees have opportunities for professional development through strategic partnerships with several outside organizations such as Central Exchange, Society of Women Engineers, and American Royal, as well as through membership in trade groups including The Fertilizer Institute, Essential Minerals Association, U.K. Salt Association and Ontario Mining Association.

Full-time employees can also take advantage of our tuition reimbursement program to further their education in subjects and degree programs that are relevant to our business.

Community

Beyond the success of our Company and our people, we are committed to supporting and creating value for communities where our employees live and work. We recognize that in many areas, we play an integral role in providing jobs and fostering local economic growth. On a larger scale, through our products, we support safety, sustainability and addressing food insecurity in communities around the world.

Focused on Company giving and employee volunteerism to positively impact our communities, Compass Minerals Cares, our community engagement program, looks to the United Nations Sustainable Development Goals to guide community engagement initiatives. We also align charitable giving and volunteer engagement with our Core Purpose to help keep people safe, feed the world and enrich lives, every day.

ENVIRONMENTAL, HEALTH AND SAFETY AND OTHER REGULATORY MATTERS

Environmental, Health and Safety Matters

Our operations subject us to an evolving set of federal, state, local and foreign environmental, health and safety (“EHS”) laws and regulations. These EHS laws and regulations regulate, or propose to regulate, the conduct of our mining and production operations, including safety procedures and process safety management; management and handling of raw and in-process materials and finished products; air and water quality impacts from our facilities; emissions of greenhouse gases (including carbon or emissions taxes); management of hazardous and solid wastes; remediation of contamination at our facilities; and post-mining land reclamation. Additional legislative and regulatory measures to address climate change and greenhouse gas emissions (including carbon or emissions taxes) are in various phases of consideration and enactment. For further discussion of how EHS laws and regulations may impact our business, see Item 1A, “Risk Factors.”

While a number of our capital projects indirectly result in environmental improvements, we estimate that our fiscal ~~2024~~2025 environmental-specific capital expenditures were $30.89 million. We expect to have approximately $32.62 million of environmental-specific capital expenditures in fiscal ~~2025~~2026 on a variety of projects. However, future capital expenditures are subject to a number of uncertainties, including changes to environmental laws and regulations, changes to our operations or unforeseen remediation requirements, and these expenditures could exceed our expectations.

As of September 30, ~~2024~~2025, we ~~had~~ recorded $12.8 million of accruals for environmental liabilities. We accrue for environmental liabilities when we believe it is probable that we will be responsible, in whole or in part, for environmental investigation or remediation activities and the expenditures for these activities are reasonably estimable. However, the extent and costs of any environmental investigation or remediation activities are uncertain and difficult to estimate and could exceed our expectations, which could materially affect our financial condition and operating results.

~~Operating~~11 ~~Requirements~~2025 ~~and~~FORM ~~Impacts~~10-K

Our operations require permits for extraction of salts and brine, air emissions, surface water discharges of process material and wastes, waste generation, injection of brine and wastewater into subsurface wells and other activities. As a result, we hold numerous environmental and mineral extraction permits, water rights and other permits, licenses and approvals from governmental authorities authorizing operations at each of our facilities. These permits, licenses and approvals are typically subject to renewals and reissuances. Expansion of our operations or production capacity, or preservation of existing rights in some cases, is also predicated upon securing any necessary permits, licenses and approvals. The terms and conditions of future

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~~EHS~~environmental ~~laws~~investigation ~~and~~or ~~regulations,~~remediation ~~permits,~~activities ~~licenses~~are ~~and~~uncertain ~~approvals may be more stringent~~ and ~~may~~difficult ~~require~~to ~~increased~~estimate ~~expenditures on our part. In addition, although we do not engage in hydraulic fracturing (commonly known as “fracking”), laws~~ and ~~regulations targeting fracking~~ could ~~lead~~exceed ~~to increased permit requirements and compliance costs for non-fracking operations, including~~ our ~~Salt operations~~expectations, which ~~require~~could ~~permitted~~materially ~~wastewater~~affect ~~disposal~~our ~~wells~~financial ~~that~~condition ~~sometimes~~and ~~receive~~operating ~~fluid waste from fracking operations as well~~results.

~~Our~~Operating ~~Cote~~Requirements ~~Blanche mine, an underground salt mine located in St. Mary Parish, Louisiana, is subject to regulation by the Mine Safety~~ and Health Administration (“MSHA”) under the Federal Mine Safety and Health Act of 1977, as amended (the “Mine Act”). MSHA is required to regularly inspect the Cote Blanche mine and issue a citation, or take other enforcement action, if an inspector or authorized representative believes that a violation of the Mine Act or MSHA’s standards or regulations has occurred. As required by MSHA, these operations are regularly inspected by MSHA personnel. See “Mine Safety Disclosures” and Exhibit 95 to this report for information concerning mine safety violations and other regulatory matters required by SEC rules. The cost of compliance and penalties for violations of the Mine Act have been and could potentially be significant. Our underground salt mines located in Goderich, Ontario, Canada and Winsford, Cheshire, U.K. are subject to similar regulations regarding health and safety, and the cost of compliance with these regulations also have been and are expected to be significant.Impacts

WeOur ~~have~~operations ~~post-closure~~require ~~reclamation~~permits ~~obligations~~for extraction of salts and brine, ~~primarily~~air ~~arising~~emissions, ~~under~~surface ~~our~~water ~~mining~~discharges ~~permits~~of orprocess bymaterial ~~agreement.~~and ~~Many~~wastes, waste generation, injection of ~~these~~brine ~~obligations~~and ~~include~~wastewater ~~requirements~~into tosubsurface ~~maintain~~wells ~~financial~~and ~~surety~~other ~~bonds~~activities. toAs ~~fund~~a ~~reclamation~~result, we hold numerous environmental and ~~site~~mineral ~~cleanup~~extraction ~~following~~permits, ~~the~~water ~~ultimate~~rights ~~closure~~and other permits, licenses and approvals from governmental authorities authorizing operations at each of our ~~mines~~facilities. These permits, licenses and approvals are typically subject to renewals and reissuances. Expansion of our operations or ~~certain~~production ~~other~~capacity, ~~facilities~~or preservation of existing rights in some cases, is also predicated upon securing any necessary permits, licenses and approvals. AsThe aterms ~~result~~and conditions of future EHS laws and regulations, permits, licenses and approvals may be more stringent and may require increased expenditures on our part. In addition, although we ~~maintain~~do ~~financial~~not ~~surety~~engage ~~bonds~~in hydraulic fracturing (commonly known as “fracking”), laws and regulations targeting fracking could lead to ~~satisfy~~increased ~~these~~permit ~~obligations.~~requirements and compliance costs for non-fracking operations, including our Salt operations, which require permitted wastewater disposal wells that sometimes receive fluid waste from fracking operations as well.

Our Cote Blanche mine, an underground salt mine located in St. Mary Parish, Louisiana, is subject to regulation by the Mine Safety and Health Administration (“MSHA”) under the Federal Mine Safety and Health Act of 1977, as amended (the “Mine Act”). MSHA is required to regularly inspect the Cote Blanche mine and issue a citation, or take other enforcement action, if an inspector or authorized representative believes that a violation of the Mine Act or MSHA’s standards or regulations has occurred. As required by MSHA, these operations are regularly inspected by MSHA personnel. See “Mine Safety Disclosures” and Exhibit 95 to this Form 10-K for information concerning mine safety violations and other regulatory matters required by SEC rules. The cost of compliance and penalties for violations of the Mine Act have been and could potentially be significant. Our underground salt mines located in Goderich, Ontario, Canada and Winsford, Cheshire, UK are subject to similar regulations regarding health and safety, and the cost of compliance with these regulations also have been and are expected to be significant.

We have post-closure reclamation obligations with respect to our mines, primarily arising under our mining permits or by agreement. Many of these obligations include requirements to maintain financial surety bonds to fund reclamation and site cleanup following the ultimate closure of our mines or certain other facilities. As a result, we maintain financial surety bonds to satisfy these obligations.

We are also impacted by the U.S. Clean Air Act (the “Clean Air Act”) and other EHS laws and regulations that regulate air emissions. These regulatory programs may require us to make capital expenditures (for example, by installing expensive emissions abatement equipment), modify our operational practices, obtain additional permits or make other expenditures, which could be significant.

We endeavor to conduct our operations in compliance with all applicable EHS laws, regulations, permits or approvals. However, because of extensive and comprehensive regulatory requirements, violations occur from time to time in our industry, and from time to time we have received notices from governmental agencies that we are not in compliance with certain EHS laws, regulations, permits or approvals and have incurred fines or penalties for these violations. Upon receipt of these notices, we evaluate the matter and take appropriate corrective actions.

In fiscal 2024, we announced a binding Voluntary Agreement (“Voluntary Agreement”) with the Utah Division of Forestry, Fire and State Lands (“FFSL”) outlining water and land conservation commitments we are making toward the long-term health of the Great Salt Lake. Among other things, the Voluntary Agreement outlines a progressive set of brine withdrawal caps for certain of our consumptive water rights, based on annual lake elevation and informed by the Great Salt Lake Strategic Plan. Although our brine consumption is reduced to 50% of our certificated water right for calendar year 2026, our brine extraction plan for 2026 is well below this limit and we do not expect any impacts to production. We may be impacted in the future if low lake levels result in further reductions as specified in the Voluntary Agreement with the Utah Division of FFSL, which outlines negotiated brine withdrawal limits based on annual lake elevation, discussed further in Item 1, “Business—Environmental, Health and Safety Matters and Other Regulatory Matters.”


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Remedial Activities

Many of our past and present facilities have been in operation for decades. Operations at these facilities have historically involved the use and handling of regulated chemical substances, salt, salt byproducts and waste by us and our predecessors.

At many of these facilities, releases and disposal of regulated substances have occurred and could occur in the future, which could require us to investigate, undertake or pay for remediation activities under the U.S. Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”) and other similar EHS laws and regulations. These laws and regulations may impose “no fault” liability on past and present owners and operators of facilities associated with the release or disposal of hazardous substances, regardless of fault or the legality of the original actions. Additionally, one past or present owner or operator may be required to bear more than its proportional share of liability if payments cannot be obtained from other responsible parties.

In addition, third parties have alleged in the past and could allege in the future that our operations have resulted in contamination to neighboring off-site areas or third-party facilities, including third-party disposal facilities for regulated substances generated by our operations, which could result in liability for us under CERCLA or other EHS laws and regulations.

We have incurred and expect to continue to incur costs and liabilities as a result of our current and former operations and our predecessor’s operations. In the past, we have agreed to undertake or pay for investigations to determine whether remediation will be required under CERCLA or otherwise to address any contamination. In other instances, we have agreed to perform remediation activities or have undertaken voluntary remediation to address identified contamination.

Other Regulatory Matters

As a global company, we are subject to complex and evolving laws and regulations. The most significant government regulations that impact our business, in addition to EHS laws and regulations, operating requirements and remedial activities, are discussed below. For further discussion of how government regulations may impact our business, see Item 1A, “Risk Factors.”

Taxes and Tariffs - We are subject to complex requirements of federal, state, local and foreign laws and regulations related to taxation, tariffs and import duties. See Part II, Item 8, Note 108. Income Taxes of our Consolidated Financial Statements for more information on taxes.

11Import ~~2024~~and ~~FORM~~Export 10Requirements, Anti-KCorruption Laws and Related Matters - We manufacture, market and sell our products both inside and outside the U.S. and ship our products across international borders. As a result, we are required to comply with a number of U.S. and international regulations, which include fair competition (antitrust) laws, import and export requirements, customs laws and anti-corruption laws, such as the U.S. Foreign Corrupt Practices Act (the “FCPA”), the UK Bribery Act and the Canadian Corruption of Foreign Public Officials Act, which generally prohibit the making or offering of improper payments to foreign government officials and political figures for the purpose of obtaining or retaining business or to gain an unfair business advantage.

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Import and Export Requirements, Anti-Corruption Laws and Related Matters - We manufacture, market and sell our products both inside and outside the U.S. and ship our products across international borders. As a result, we are required to comply with a number of U.S. and international regulations, which include fair competition (antitrust) laws, import and export requirements, customs laws and anti-corruption laws, such as the U.S. Foreign Corrupt Practices Act (the “FCPA”), the U.K. Bribery Act and the Canadian Corruption of Foreign Public Officials Act, which generally prohibit the making or offering of improper payments to foreign government officials and political figures for the purpose of obtaining or retaining business or to gain an unfair business advantage.

Employment and Labor Relations - We are also subject to numerous federal, state, local and foreign laws and regulations governing our relationships with our employees, including those relating to wages, overtime, labor matters, working conditions, hiring and firing, non-discrimination, immigration, work permits and employee benefits.

Impacts of Regulatory Matters

Costs of compliance with laws and regulations, including management effort, time and resources, have been and are expected to continue to be significant. These costs include the capital projects related to environmental improvements discussed above. New or proposed regulatory programs (including EHS regulatory programs), as well as future interpretations and enforcement of existing laws and regulations, may impact our business significantly, our ability to serve customers, preclude us from conducting business with governmental entities, require modification to our facilities, lead to substantial increases in operating costs, penalties, injunctions, civil remedies or fines or cause interruptions, modifications or a termination of operations, the extent toof which we cannot predict. Anticipating future compliance obligations, implementing compliance plans and estimating future costs can be particularly challenging while laws and regulations are under development and have not been adopted. For further discussion, see Item 1A, “Risk Factors.”

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ITEM 1A. RISK FACTORS

We are subject to a number of risks ~~which~~that could have a material adverse effect on our business, financial condition, results of operations and the value of our securities. You should carefully consider the following risks and all of the information set forth in this ~~report~~Form 10-K. The risks described below are not the only ones facing our company. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial may also materially and adversely affect our business, financial condition or results of operations.

Risks Related to our Restatement and Internal Controls

Management identified material weaknesses in the Company’s internal control over financial reporting that resulted in errors in financial statements. If the Company fails to remediate the material weaknesses or experiences additional material weaknesses in the future, it may be unable to accurately and timely report financial results or comply with the requirements of being a public company, which could cause the price of the Company’s common stock to decline and harm its business.

Management identified material weaknesses in internal control over financial reporting in conjunction with the restatement described in the Explanatory Note of our Form 10-K/A, filed with the SEC on October 29, 2024. The description of the material weaknesses that were determined to exist as of September 30, ~~2023~~2024 and ~~2024~~September 30, 2023 is included under Part II Item 9A of this Form 10-K.

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected in a timely basis.

While we are taking steps to address the identified material weaknesses and prevent additional material weaknesses from occurring, it cannot be assured that the measures the Company has taken to date, and is continuing to implement, will be sufficient to remediate the material weaknesses or to avoid potential future material weaknesses. Accordingly, there could continue to be a reasonable possibility that the material weaknesses identified, or other material weaknesses or deficiencies identified in the future, could result in a misstatement of accounts or disclosures that would result in a material misstatement of the Company’s financial statements that would not be prevented or detected on a timely basis or cause us to fail to meet our obligations under securities laws, stock exchange listing rules, or debt instrument covenants to file periodic financial reports on a timely basis. Any of these failures could result in adverse consequences that could materially and adversely affect the Company’s business, including an adverse impact on the market price of its common stock, potential action by the SEC, shareholder lawsuits, delisting of the Company’s stock, potential covenant defaults, and general damage to its reputation. The Company has incurred and expects to incur additional costs to rectify the material weaknesses or new issues that may emerge, and the existence of these issues could adversely affect its reputation or investor perceptions. The Company maintains director and officer liability insurance, for which it must pay substantial premiums. The additional reporting and other obligations resulting from the material weaknesses, including any litigation or regulatory inquires that may result therefrom, increase legal and financial compliance costs and the costs of related legal, accounting and administrative activities.

Operational Risks

Our mining and industrial operations can involve high-risk activities.

Our operations can involve or be subject to significant risks and hazards, including environmental hazards, industrial accidents and natural disasters. Our underground salt mining operations and related processing activities have in the past, and may in the future, be subject to hazards such as industrial and mining accidents, fire, natural disasters, explosions, unusual or unexpected geological formations or movements, water intrusion and flooding. For example, MSHA considers our Cote Blanche mine to be a “gaseous mine” and, as a result, is subject to a heightened risk of explosion and fire. These potential risks include damage or impacts from pipeline and storage tank leaks and ruptures; explosions and fires; mechanical failures; earthquakes, tornadoes, hurricanes, flooding and other natural disasters; and chemical spills and other discharges or releases of toxic or hazardous substances or gases at our sites or during transportation.

These hazardous activities pose significant management challenges and could result in loss of life, a mine shutdown, damage to or destruction of our properties and surrounding properties, production facilities or equipment, production delays or business ~~interruption. Our insurance coverage may be insufficient to cover all losses or claims associated with our operations, including these operational risks.~~

~~Geological~~14 ~~conditions~~2025 ~~could~~FORM ~~lead to a mine shutdown, increased costs, production delays and product quality issues, which could adversely affect results of our operations.~~ 10-K

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~~significant~~interruption. ~~water~~Our ~~inflows~~insurance ~~and~~coverage ~~flooding~~may atbe ~~any~~insufficient ~~of our underground mines, which could result in a mine shutdown, serious injuries, loss of life, increased operational costs, production delays, damage~~ to ~~our~~cover ~~mineral~~all ~~deposits~~losses ~~and~~or ~~equipment~~claims ~~damage.~~associated Wewith ~~have minor water inflows at~~ our Cote Blanche and Goderich salt mines that we actively monitor and manage. Underground mining also poses the potential risk of mine collapse or ceiling collapse because of the mine geology and the rate and volume of minerals extractedoperations, ~~among~~including ~~other~~these ~~potential~~operational ~~causes~~risks. ~~We could also have a ceiling collapse in the brine wells used to extract salt for mechanical evaporation, which could increase costs and cause production delays.~~

Geological conditions could lead to a mine shutdown, increased costs, production delays and product quality issues, which could adversely affect results of our operations.

Our salt mining operations involve complex processes, which are affected by the mineralogy of the mineral deposits and structural geologic conditions and are subject to related risks. For example, unexpected geological conditions could lead to significant water inflows and flooding at any of our underground mines, which could result in a mine shutdown, serious injuries, loss of life, increased operational costs, production delays, damage to our mineral deposits and equipment damage. We have minor water inflows at our Cote Blanche and Goderich salt mines that we actively monitor and manage. Underground mining also poses the potential risk of mine collapse or ceiling collapse because of the mine geology and the rate and volume of minerals extracted, among other potential causes. We could also have a ceiling collapse in the brine wells used to extract salt for mechanical evaporation, which could increase costs and cause production delays.

Variations in the mineralogy and geology of our mineral deposits have limited, and could continue to limit, our ability to extract these deposits, increase our extraction costs and impact the purity and suitability of extracted minerals to create products for sale and to meet customer specifications. This could adversely impact our ability to fulfill our contracts, resulting in significant contractual penalties and loss of customers.

The results of our operations are dependent on and vary due to weather conditions and lake level fluctuations. Additionally, adverse weather conditions or significant changes in weather patterns could adversely affect us.

Weather conditions, including amounts, timing and duration of wintry precipitation and snow events, excessive hot or cold temperatures, rainfall and drought, can significantly impact our sales, production, costs and operational results and impact our customers. From year to year, sales of our deicing products and profitability of the Salt segment are affected by weather conditions in our markets. Any prolonged change in weather patterns in our markets, as a result of climate change or otherwise, could have a material impact on the results of our operations.

In addition, our ability to produce SOP, sodium chloride and magnesium chloride, from our solar evaporation ponds located near Ogden, Utah, is dependent upon sufficient lake brine levels in the Great Salt Lake and hot, arid summer weather conditions. Prolonged periods of precipitation, lack of sunshine, cooler weather or increased mountain water run-off during the evaporation season could reduce mineral concentrations and evaporation rates, leading to decreases in our production levels. Other factors such as state or federal actions to manage the salinity of the Great Salt Lake could also alter north arm lake levels and disrupt our evaporation production cycle, impact our access to ambient lake brine in the Great Salt Lake or increase our related capital expenditures and production costs. Similarly, in recent years drought, or decreased mountain snowfall and associated fresh water run-off have reduced brine intake levels, ~~which~~impacting ~~could~~subsequent ~~also~~harvests ~~impact~~in ~~mineral~~2024 ~~composition~~ and ~~our~~2025. ~~mineral~~Future ~~harvesting~~occurrences ~~process,~~of ~~amount~~drought and/or ~~timing.~~reduced ~~Lake~~runoff ~~level fluctuations and other factors~~ could ~~alter~~also ~~brine~~impact ~~levels or~~ mineral ~~concentration~~composition ~~levels,~~and ~~which may disrupt~~ our ~~typical~~mineral ~~two-~~harvesting toprocess, ~~three-year~~amount ~~evaporation~~and ~~production cycle~~timing. Similar factors could negatively impact the lake level and concentration of sulfates at the Big Quill Lake, impacting the operations at our Wynyard, Saskatchewan, Canada, facility., ~~The~~and ~~occurrence~~potentially ofleading ~~these events at the Great Salt Lake or Big Quill Lake (as a result of climate change or otherwise) could lead~~ to decreased production levels, increased operating costs and significant additional capital expenditures.

Weather conditions have historically caused volatility in the agricultural industry (and indirectly in our results of operations) by causing crop failures or significantly reduced harvests, which can adversely affect application rates, demand for our SOP products and our customers’ creditworthiness. Weather conditions can also lead to a reduction in farmable acres, due to flooding, drought or wildfires, ~~which could also adversely impact the number of acres planted, growers’ crop yields and the uptake of plant nutrients,~~ reducing the need for application of plant nutrition products for the next planting season, which could result in lower demand for our SOP products and impact sale prices. ~~Weather conditions also impact our fire retardant business, since hotter and drier summer weather is generally correlated with a higher prevalence of wildfires.~~

Operations at our Ogden, Utah, facility are dependent on ambient brine from the Great Salt Lake, and changes in lake brine levels or any limitations on our continued ability to access ambient lake brine in the Great Salt Lake could adversely affect us.

Our Ogden facility produces three mineral salts - specifically, SOP, sodium chloride and magnesium chloride products - from the high mineral concentrations within the ambient lake brine in the Great Salt Lake. Our ability to produce SOP, sodium chloride and magnesium chloride at our Ogden facility is dependent upon, among other matters, sufficient lake elevations in the Great Salt Lake and our continued ability to maintain, renew or acquire the permits, licenses and approvals required to access ambient lake brine in the Great Salt Lake.

Sustained drought (as a result of climate change or otherwise), lower lake levels or increased mineral concentrations in the Great Salt Lake could impact mineral composition and our mineral harvesting process, amount and timing. Lake level fluctuations and other factors, including state or federal actions to manage the salinity of the Great Salt Lake, could alter north arm lake levels and may disrupt our evaporation production cycle, impact our access to ambient lake brine in the Great Salt Lake or increase our related capital expenditures and production costs.

Our operations are conducted primarily through a limited number of key production and distribution facilities, and we are also dependent on critical equipment.

We conduct our operations through a limited number of key production and distribution facilities. These facilities include our underground salt mines, our evaporation plants, our solar evaporation ponds and facilities and the distribution facilities, depots and ports owned by us and third parties. Many of our products are produced at one or two of these facilities. Any disruption of operations at one of these facilities could significantly affect production of our products, distribution of our products or our ability to fulfill our contractual obligations, which could damage our customer relationships.

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For example, our two North American salt mines together constituted approximately 70% of our salt production capacity as of September 30, ~~2024~~2025, and supply most of the salt sold by our North American highway deicing business and significant portions of the salt sold by our consumer and industrial business. A production interruption at one of our salt mines could adversely affect our ability to fulfill our salt contracts and our ability to secure future contracts in affected markets or other markets or could lead to increased costs to service customers from alternative supply sources. Our salt mines also have limited access ways and shafts and any inability to use these access ways and shafts could impede our ability to operate or cause a production interruption. In addition, we only have a limited number of distribution facilities in the markets in which we sell our salt products. Failure to have our salt products at a specific distribution facility when needed (for example during a snow event) could adversely impact our ability to fulfill our highway deicing sales contracts, resulting in significant contractual penalties and loss of customers.

Similarly, our plant nutrition product, SOP, is only produced at two locations: our solar evaporation ponds and facilities located adjacent to the Great Salt Lake near Ogden, Utah, and our facility near Big Quill Lake in Saskatchewan, Canada. SOP production from these facilities could be disrupted or negatively impacted by structural damage, as a result of dike failure or other factors, which could result in reduced sales. A production interruption or disruption at one or more of our facilities could result in a loss of customers, a loss in revenue or subject us to fines or penalties.

Our operations depend upon critical equipment, such as continuous mining machines, hoists, conveyor belts, bucket elevators, loading equipment, baghouses, compactors and dryers. This equipment could be damaged or destroyed, suffer breakdowns or failures or deteriorate due to wear and tear sooner than we estimate, and we may be unable to replace or repair the equipment in a timely manner or at a reasonable cost. If these events occur, we may incur additional maintenance and capital expenditures, our operations could be materially disrupted and we may not be able to produce and ship our products.

Our business is capital intensive, and the inability to fund necessary capital expenditures or successfully complete our capital projects could have an adverse effect on our growth and profitability.

In recent years, we have made significant expenditures on large capital projects, including a shaft relining project at our Goderich mine and upgrading the barge dock at the Cote Blanche mine. In addition, maintaining our existing facilities requires significant capital expenditures, which may fluctuate materially. We also may make significant capital expenditures in the future to expand or modify our existing operations, including projects to expand or improve our facilities (including new mine level development and mine expansion to access additional mineral deposits, or to augment our Ogden facility’s pond storage capacity) or equipment and projects to improve our computer systems, information technology and operations technology. These activities or other capital improvement projects may require the temporary suspension of production at our facilities, which could have a material adverse effect on the results of our operations.

Any capital project we undertake involves risks, including cost overruns, delays and performance uncertainties, and could interrupt our ongoing operations. The expected benefits from any of our capital projects may not be realized in accordance with our projections. Our capital projects may also result in other unanticipated adverse consequences, such as the diversion of management’s attention from other operational matters or significant disruptions to our ongoing operations.

Although we currently finance most of our capital expenditures through cash provided by operations, we also may depend on increased borrowing or other financing arrangements to fund future capital expenditures. If we are unable to obtain suitable financing on favorable terms or at all, we may not be able to complete future capital projects and our ability to maintain or expand our operations may be limited. The occurrence of these events could have a material adverse effect on our business, financial condition and results of operations.

We face numerous uncertainties in estimating our economically recoverable reserves and resources, and inaccuracies in our estimates could result in lower than expected revenues, higher than expected costs and decreased profitability.

A mineral is economically recoverable when the price at which it can be sold exceeds the costs and expenses of mining, processing and selling the mineral. Forecasts of our future performance are based on, among other things, estimates of our mineral reserves and resources. Our mineral reserve and resource estimates of the remaining tons of minerals in our mines and other mining properties are based on many factors, including engineering, economic and geological data assembled and analyzed by our staff and third parties, which include various engineers and geologists, the area and volume covered by our mining rights, assumptions regarding our extraction rates and duration of mining operations, and the quality of in-place reserves and resources. The reserve and resource estimates as to both quantity and quality are updated on a routine basis to reflect, among other matters, production of minerals from our mining properties and new mining or other data received.


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There are numerous uncertainties inherent in estimating quantities and qualities of minerals and costs to mine recoverable reserves and resources, including many factors beyond our control. Estimates of mineral reserves and resources necessarily depend upon a number of variable factors and assumptions, any one of which may, if incorrect, result in an estimate that varies considerably from actual results. These factors and assumptions include:

•geologic and mining conditions, including our ability to access certain mineral deposits as a result of the nature of the geologic formations of our salt mines or other factors, which may not be fully identified by available exploration data and may differ from our experience in areas we currently mine;

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•demand for our minerals;

•current and future market prices for our minerals, contractual arrangements, operating costs and capital expenditures;

•taxes and development and reclamation costs;

•mining technology and processing improvements;

•the effects of legislation or interpretations thereof, or regulation by governmental agencies;

•the ability to obtain, maintain and renew all required permits;

•employee health and safety;

•historical production from the area compared with production from other producing areas; ~~and~~

•the indigenous interest and rights of the First Nation organization in the provinces of Saskatchewan, Ontario and Nova Scotia, and the related consultation requirements applicable to us in these provinces with First Nation, which may impact our ability to obtain permits, lease extensions, mine and conduct our business; and

•our ability to convert all or any part of our resources to economically extractable mineral reserves.

As a result, actual tonnage recovered from identified mining properties and revenues and expenditures with respect to our reserves and resources may vary materially from estimates. Thus, these estimates may not accurately reflect our actual reserves and resources. Any material inaccuracy in our estimates related to our reserves or resources could result in lower than expected revenues, higher than expected costs or decreased profitability, which could materially and adversely affect our business, results of operations, financial position and cash flows. Additionally, our reserve and resource estimates may be adversely affected in the future by interpretations of, or changes to, the SEC’s property disclosure requirements for mining companies.

Strikes, other forms of work stoppage or slowdown and other union activities could disrupt our business and negatively impact our financial results.

Nearly 50% of our workforce in the U.S., Canada and the ~~U.K.~~UK is represented by ~~collective bargaining agreements~~CBAs. Of our 12 ~~collective~~CBAs ~~bargaining agreements~~ in effect on September 30, ~~2024, six will expire in fiscal~~ 2025 ~~(including our Cote Blanche mine), four will expire in fiscal 2026 (including our Goderich mine), and two will expire in fiscal 2027.~~ :

~~Unsuccessful~~•Six ~~contract~~expired ~~negotiations,~~in ~~adverse~~fiscal ~~labor~~2025 ~~relations~~(including ~~at any of~~ our ~~locations~~Cote orBlanche ~~other factors have in the past~~mine), ~~and~~four ~~could~~of ~~in the future, result in strikes, work stoppages, work slowdowns, dissatisfied employees or other actions,~~ which ~~could~~were ~~disrupt~~renewed/renegotiated ~~our business~~ and ~~operations.~~two ~~These~~are ~~disruptions~~still ~~could negatively impact our business, our operations, our ability to produce or sell our products, our ability to service our customers and our ability to recruit and retain personnel and could result~~ in ~~significant~~the ~~additional~~process ~~costs~~of asbeing ~~well~~negotiated; ~~as adversely affect our reputation, financial condition and operating results.~~

~~Our~~•Four ~~production~~will ~~processes~~expire ~~rely~~in onfiscal ~~the~~2026 ~~consumption~~(including ofour ~~natural~~Goderich ~~gas~~mine, ~~electricity~~which ~~and~~have ~~certain~~393 ~~other~~positions ~~raw~~represented ~~materials. A~~by ~~significant~~a ~~interruption~~CBA); inand ~~the supply or an increase in the price of any of these could adversely affect our business.~~

~~Energy~~•Two ~~costs,~~will ~~primarily~~expire natural gas and electricity, represent a substantial part of our total production costs. Our profitability is impacted by the price and availability of natural gas and electricity we purchase from third parties. Natural gas is a primary energy source used in ~~the~~fiscal ~~mechanically evaporated salt production process~~2027. Our contractual arrangements for the supply of natural gas have terms of up to three years, do not specify quantities and are automatically renewed unless either party elects not to do so. We do not have arrangements in place with back-up suppliers. We use natural gas derivatives to hedge some of our financial exposure to the price volatility of natural gas. A significant increase in the price of energy that is not recovered through an increase in the price of our products or covered through our hedging arrangements, or an extended interruption in the supply of natural gas or electricity to our production facilities, could have a material adverse effect on our business, financial condition and results of operations.

WeUnsuccessful ~~use~~contract ~~KCl~~negotiations, instrained ~~our~~labor ~~salt~~relations ~~and~~at ~~plant~~any ~~nutrition~~of ~~operations. Large~~our ~~price~~locations ~~fluctuations~~or inother ~~KCl~~labor-related ~~can~~factors ~~occur~~have ~~without a corresponding change~~ in the ~~sales~~past, ~~price~~and ~~of our products sold to our customers. This~~ could ~~change~~in the ~~profitability~~future, ofresult ~~our~~in ~~products~~strikes, ~~that~~work ~~require KCl~~stoppages, ~~which~~work ~~could~~slowdowns, ~~materially~~or ~~affect~~other ~~the~~forms ~~results~~ of ~~our~~labor ~~operations~~disruption. InThese ~~certain~~disruptions ~~cases,~~may welead ~~also~~to ~~source~~increased ~~raw~~operational ~~materials~~costs, ~~from~~delays ain ~~sole~~fulfilling ~~supplier~~customer commitments and ~~cannot~~reputational ~~guarantee~~harm. ~~that~~Ultimately, ~~any~~they ~~supplier~~could ~~will~~adversely beaffect ~~able to meet~~ our ~~requirements~~financial ~~and any changes in their operations~~condition, ~~including~~operating ~~prolonged~~results ~~outages,~~and ~~could~~long-term ~~have~~strategic ~~a material adverse effect on our business~~objectives.

Our production processes rely on the consumption of natural gas, electricity, diesel, and certain other raw materials. A significant interruption in the supply or an increase in the price of any of these could adversely affect our business.

Energy costs, primarily natural gas, electricity, and diesel represent a substantial part of our total production costs. Our profitability is impacted by the price and availability of natural gas, electricity, and diesel we purchase from third parties. Natural gas is a primary energy source used in the mechanically evaporated salt production process. We do not have arrangements in place with back-up suppliers. We use natural gas derivatives to hedge some of our financial exposure to the price volatility of natural gas. A significant increase in the price of energy that is not recovered through an increase in the price of our products or covered through our hedging arrangements, or an extended interruption in the supply of natural gas or electricity to our production facilities, could have a material adverse effect on our business, financial condition and results of operations.

We use KCl in our salt and plant nutrition operations. Large price fluctuations in KCl can occur without a corresponding change in the sales price of our products sold to our customers. This could change the profitability of our products that require KCl, which could materially affect the results of our operations. In certain cases, we also source raw materials from a sole


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supplier and cannot guarantee that any supplier will be able to meet our requirements and any changes in their operations, including prolonged outages, could have a material adverse effect on our business.

Competition, Sales and Pricing Risks

The demand for our products is seasonal.

The demand for our salt and plant nutrition products is seasonal, and the degree of seasonality can change significantly from year to year due to weather conditions, including the number of snow events, rainfall, drought and other factors.

Our salt deicing business is seasonal. On average, in each of the last three years, approximately two-thirds of our deicing product sales occurred during the North American and European winter months of November through March. Winter weather events are not predictable, yet we must stand ready to deliver deicing products to local communities with little advance notice under the requirements of our highway deicing contracts. As a result, we attempt to stockpile our highway deicing salt throughout the year to meet estimated demand for the winter season. Failure to deliver under our highway deicing contracts may result in significant contractual penalties and loss of customers. Servicing markets typically serviced by one production facility with product from an alternative facility may add logistics and other costs and reduce profitability.

Our plant nutrition business is also seasonal. As a result, we and our customers generally build inventories during the low demand periods of the year (which are typically winter and summer, but can vary due to weather and other factors) to ensure timely product availability during the peak sales seasons (which are typically spring and autumn, but can also vary due to weather and other factors).

If seasonal demand is greater than we expect, or we experience increased costs and product shortages, our customers may turn to our competitors for products that they would otherwise have purchased from us. If seasonal demand is less than we expect, we may have excess inventory to be stored (in which case we may incur increased storage costs) or liquidated (in which case the selling price may be below our costs). If prices for our products rapidly decrease, we may be subject to inventory write-downs. Our inventories may also become impaired through obsolescence or the quality may be impaired if our inventories are not stored properly. Low seasonal demand could also lead to increased unit costs if our production levels are curtailed.

Variables impacting effective inventory management may adversely impact our performance.

Efficient inventory management is essential to our performance. We must maintain appropriate inventory levels and product mix to meet customer demand, while minimizing costs related to storing and holding excess inventory. If our inventory management decisions do not accurately align to demand or otherwise result in excess inventory, as has happened in the past, our financial results may be adversely impacted by markdowns, impairment charges, or impact to subsequent period production rates. Conversely, if we do not maintain enough inventory to satisfy the demand of our customers, we may lose business to our competitors. Any such inefficiencies in inventory management could negatively affect our operations and results.

Anticipated changes in potash prices and customer application rates can have a significant effect on the demand and price for our plant nutrition products.

When customers anticipate increasing potash selling prices, they tend to accumulate inventories in advance of the expected price increase. Similarly, customers tend to delay their purchases when they anticipate future selling prices for potash products will stabilize or decrease. These customer expectations can lead to a lag in our ability to realize price increases for our SOP products and adversely impact our sales volumes and selling prices.

Growers’ decisions to purchase plant nutrition products and the application rate for potash products depend on many factors, including expected grower income, crop prices, plant nutrition product prices, commodity prices, input prices and nutrient levels in the soil. Customers are more likely to decrease purchases and application rates when they expect declining agricultural economics or relatively high plant nutrient costs, other input costs or elevated soil nutrient levels. This variability can materially impact our prices and volumes sold.


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Our products face strong competition and if we fail to successfully attract and retain customers and invest in capital improvements, productivity, quality improvements and product development, sales of our products could be adversely affected.

We encounter strong competition in many areas of our business and our competitors may have significantly more financial resources than we do. Competition in our product lines is based on a number of factors, including product quality and performance, logistics (especially in Salt distribution), brand reputation, price and quality of customer service and support. Many of our customers attempt to reduce the number of vendors from which they purchase in order to increase their efficiency. To remain competitive, we need to invest in manufacturing, productivity, product innovation, marketing, customer service and support and our distribution networks. We may not have sufficient resources to continue to make such investments or maintain our competitive position. We may have to adjust our prices, strategy, product innovation, distribution or marketing efforts to stay competitive.

Changes in competitors’ production, geographic or marketing focus could have a material impact on our business. We face global competition from new and existing competitors who have entered or may enter the markets in which we sell, particularly in our plant nutrition business. Some of our competitors may have greater financial and other resources than we do or are more diversified, making them less vulnerable to industry downturns and better positioned to pursue new expansion and development opportunities. Our competitive position could suffer if we are unable to expand our operations through investments in new or existing operations or through acquisitions, joint ventures or partnerships.

Inflation could result in higher costs and decreased profitability.

Our business can be affected by inflation, including increases in freight rates, prices for energy and other costs. Sustained inflation could result in higher costs for transportation, energy, materials, supplies and labor. Our ability to recover inflation-driven cost increases may be constrained by the terms of our contracts, the competitive nature of the bidding process, and the economic and industry conditions prevailing in the markets where we operate. Significant inflation presents a risk of materially increasing our costs and adversely impacting our profitability and overall financial performance.

Increasing costs or a lack of availability of transportation services could have an adverse effect on our ability to deliver products at competitive prices.

Transportation and handling costs are a significant component of our total delivered product cost, particularly for our salt products. The high relative cost of transportation favors producers whose mines or facilities are located near the customers they serve. We contract (directly and, from time to time, through third parties) bulk shipping vessels, barges, trucking and rail services to move our products from our production facilities to distribution outlets and customers. A reduction in the dependability or availability of transportation services, a significant increase in transportation service rates, adverse weather and changes to water levels on the waterways used for our products could impair our ability to deliver our products economically to our customers or expand our markets. For example, when the Mississippi river floods significantly or if water levels are significantly reduced by severe drought conditions (as they were in 2023), barges may be unable to traverse the river system and we may be prevented from delivering our salt products to our depots and customers on a timely basis, which could increase costs to deliver our products and adversely impact our ability to fulfill our contracts, resulting in significant contractual penalties and loss of customers.

In addition, diesel fuel is a significant component of our transportation costs. Some of our customer contracts allow for full or partial recovery of changes in diesel fuel costs through an adjustment to the selling price. However, a significant increase in the price of diesel fuel that is not passed through to our customers could materially increase our costs and adversely affect our financial results.

Significant transportation costs relative to the cost of certain of our products, including our salt products, may limit our ability to increase our market share or serve new markets.


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Risks associated with our international operations and sales and changes in economic and political environments could adversely affect our business and earnings.

We have significant operations in Canada and the UK. Our fiscal 2025 sales outside the U.S. were 30% of our total fiscal 2025 sales. Our overall success as a global business depends on our ability to operate successfully in differing economic, political and cultural conditions. Our international operations and sales are subject to numerous risks and uncertainties, including:

•economic developments including changes in currency exchange rates, inflation risks, exchange controls, tariffs, economic sanctions, other trade protection measures and import or export licensing requirements;

•difficulties and costs associated with complying with laws, treaties and regulations, including tax, labor and data privacy laws, treaties and regulations, and changes to laws, treaties and regulations;

•restrictions on our ability to own or operate subsidiaries, make investments or acquire new businesses;

•restrictions on our ability to repatriate earnings from our non-U.S. subsidiaries to the U.S. or the imposition of withholding taxes on remittances and other payments by our subsidiaries;

•political developments, government deadlock, political instability, political activism, terrorist activities, civil unrest and international conflicts;

•uncertain and varying enforcement of laws and regulations and weak protection of intellectual property rights; and

•risks relating to epidemics and pandemics and effects therefrom.

A significant portion of our cash flow is generated in Canadian dollars and British pounds sterling and our consolidated financial results are reported in U.S. dollars. Our reported results can significantly increase or decrease based on exchange rate volatility after translation of our results into U.S. dollars. Exchange rate fluctuations could also impact our ability to meet interest and principal payments on our U.S. dollar-denominated debt. In addition, we incur currency transaction risk when we enter into a purchase or a sales transaction using a currency other than the local currency of the transacting entity. We may not be able to effectively manage our currency risks. For more information, see Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Effects of Currency Fluctuations and Inflation,” and Part II, Item 7A, “Quantitative and Qualitative Disclosures About Market Risk.”

In addition, we may face more competition in periods when foreign currency exchange rates are favorable to our competitors. A relatively strong U.S. dollar increases the attractiveness of the U.S. market for some of our international competitors while decreasing the attractiveness of other markets to us.

Conditions in the sectors where we sell products and supply and demand imbalances for competing products can impact the price and demand for our products.

Conditions in the North American agricultural sectors can significantly impact our plant nutrition business. The agricultural sector can be affected by a number of factors, including weather conditions, field conditions (particularly during periods of traditionally high plant nutrition application), government policies, tariffs and import and export markets.

Demand for our products in the agricultural sector is affected by crop prices, crop selection, planted acreage, application rates, crop yields, product acceptance, population growth, livestock consumption and changes in dietary habits, among other things. Supply is affected by available capacity, operating rates, raw material costs and availability, feasible transportation, government policies, tariffs and global trade. In addition, the demand and price of our SOP products can be affected by factors such as plant disease.

MOP is the least expensive form of potash fertilizer and, consequently, it is the most widely used potassium source for most crops. SOP is utilized by growers for many high-value crops, especially crops for which low-chloride content fertilizers or the presence of sulfur improves quality and yield, such as almonds and other tree nuts, avocados, citrus, lettuce, tobacco, grapes, strawberries and other berries. Lower prices or demand for these crops could adversely affect demand for our products and the results of our operations.

When the demand and price of potash are high, our competitors are more likely to increase their production and invest in increased production capacity. An over-supply of MOP or SOP domestically or worldwide could unfavorably impact the prices we can charge for our SOP, as a large price disparity between potash products could cause growers to choose MOP or other less-expensive alternatives, which could adversely impact our sales volume and the results of our operations.

Similarly, conditions in the Salt sector can significantly impact our Salt segment. These conditions include weather conditions as well as import and export markets. Supply and demand imbalances can be caused by a number of factors, including weather conditions, operating rates, transportation costs and global trade.


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Financial Risks

Our indebtedness and any inability to pay our indebtedness could adversely affect our business and financial condition.

We have a significant amount of indebtedness and may incur additional debt in the future. As of September 30, ~~2024~~2025, we had $~~922~~845.8 million of outstanding indebtedness, ~~including $383.9 million of borrowings under our senior secured credit facilities,~~ which are further described in Part II, Item 8, Note 1210. Long Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements. We pay significant interest on our indebtedness, with variable interest on ~~our~~borrowings ~~borrowing~~made under both our ~~senior~~revolving ~~secured~~ credit facilities and account receivable securitization facility based on prevailing interest rates. Significant increases in interest rates will increase the interest we pay on our debt. Our indebtedness could:

•require us to agree to less favorable terms, including higher interest rates, in order to incur additional debt, and otherwise limit our ability to borrow additional money or sell our stock to fund our working capital, capital expenditures and debt service requirements;

•impact our ability to implement our business strategy and limit our flexibility in planning for, or reacting to, changes in our business as well as changes to economic, regulatory or other competitive conditions;

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•place us at a competitive disadvantage compared to our competitors with greater financial resources;

•make us more vulnerable to a downturn in our business or the economy;

•require us to dedicate a substantial portion of our cash flow from operations to the repayment of our indebtedness, thereby reducing the availability of our cash flow for other purposes;

•restrict us from making strategic acquisitions or cause us to make non-strategic divestitures; and

•materially and adversely affect our business and financial condition if we are unable to meet our debt service requirements or obtain additional financing.

In the future, we may incur additional indebtedness or refinance our existing indebtedness. If we incur additional indebtedness or refinance, the risks that we face as a result of our leverage could increase. Financing may not be available when needed or, if available, may not be available on commercially reasonable or satisfactory terms. Any downgrades from credit rating agencies such as Moody’s or Standard & Poor’s may adversely impact our ability to obtain financing or the terms of such financing.

Our ability to make payments on our indebtedness, refinance our indebtedness and fund planned capital expenditures will depend on our ability to generate future cash flows from operations. This, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. There can be no assurance that our business will generate sufficient cash flows from operations or that future borrowings will be available to us under our revolving credit facility in an amount sufficient to enable us to make payments with respect to our indebtedness or to fund our other liquidity needs. If this were the case, we might need to refinance all or a portion of our indebtedness on or before maturity, sell assets, reduce or delay capital expenditures or seek additional equity financing. Our inability to obtain needed financing or generate sufficient cash flows from operations may require us to abandon or curtail capital projects, strategic initiatives or other investments, cause us to divest our business or impair our ability to make acquisitions, enter into joint ventures or engage in other activities, which could materially impact our business.

The agreements governing our indebtedness impose restrictions that may limit our ability to operate our business or require accelerated debt payments.

Our agreements governing our indebtedness contain covenants that limit our ability to:

•incur additional indebtedness or contingent obligations or grant liens;

•pay dividends or make distributions to our stockholders;

•repurchase or redeem our stock;

•make investments or dispose of assets;

•prepay, or amend the terms of, certain junior indebtedness;

•engage in sale and leaseback transactions;

•make changes to our organizational documents or fiscal periods;

•create or permit certain liens on our assets;

•create or permit restrictions on the ability of certain subsidiaries to make certain intercompany dividends, investments or asset transfers;

•enter into new lines of business;

•enter into transactions with our stockholders and affiliates; and

•acquire the assets of, or merge or consolidate with, other companies.

~~The~~21 credit agreement governing our senior secured credit facilities also requires us to maintain financial ratios, including an interest coverage ratio and a total leverage ratio, which we may be unable to maintain. As of September 30, 2024, our total net leverage ratio (as calculated under the terms of our credit agreement) was 4.89x. We would be in default under our credit agreement if our net leverage ratio exceeds 6.5x as of the last day of any quarter through the fiscal quarter ended September 30, 2025, ~~gradually~~FORM ~~stepping down to 4.5x for the fiscal quarter ended December 31, 2026 and thereafter.~~10-K


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The credit agreement governing our senior secured credit facilities also requires us to maintain financial ratios, including a consolidated interest coverage ratio and a consolidated first lien net leverage ratio, which we may be unable to maintain. As of September 30, 2025, our consolidated first lien net leverage ratio (as calculated under the terms of our credit agreement) was 0.01x. We would be in default under our credit agreement if our consolidated first lien net leverage ratio exceeds 2.75x as of the last day of any quarter through the fiscal quarter ended September 30, 2025, stepping down to 2.5x for the fiscal quarter ended December 31, 2025 and thereafter.

Various risks, uncertainties and events beyond our control could affect our ability to comply with the covenants, financial tests and ratios required by the agreements governing our indebtedness. If we default under our agreements governing our indebtedness, our lenders could cease to make further extensions of credit, accelerate payments under our other debt instruments (including hedging instruments) that contain cross-acceleration or cross-default provisions and foreclose upon any collateral securing that debt as well as restrict our ability to make certain investments and payments, pay dividends, repurchase our stock, enter into transactions with affiliates, make acquisitions, merge and consolidate, or transfer or dispose of assets.

If our lenders were to require immediate repayment, we may need to obtain new financing to be able to repay them immediately, which may not be available or, if available, may not be available on commercially reasonable or satisfactory terms. Under these circumstances, we might not have sufficient funds or other resources to satisfy all of our obligations.

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We are subject to tax liabilities which could adversely impact our profitability, cash flow and liquidity.

We are subject to income tax primarily in the U.S., Canada and the UUK.K. Our effective tax rate, tax expense, and cash flows could be adversely affected by changes in the mix of earnings in ~~countries~~jurisdictions with differing statutory tax rates, changes in the ~~valuation of deferred~~ tax ~~assets~~laws and ~~liabilities~~regulations and the discovery of new information in the course of our tax return preparation process. Our effective tax rate, ~~tax expense and cash flows~~ could also be adversely affected by changes in the valuation of deferred tax ~~laws~~assets and liabilities. We are also subject to audits in various jurisdictions and may be assessed additional taxes as a consequence of an audit.

A Canadian provincial tax ~~authorities~~authority ~~have~~has challenged our tax positions and assessed additional taxes and interest on us, which are described in Part II, Item 8, Note 108. toIncome Taxes of our Consolidated Financial Statements. These tax assessments and future tax assessments could be material if the disputes are not resolved in our favor. Also see Part II, Item 8, Note 18. Subsequent Event for discussion of subsequent event concerning settlement of tax dispute for 2002-2018.

In the ordinary course of our business, there are many transactions and calculations that could be challenged by taxing authorities. This includes the values charged on the transfer of products between our subsidiaries. Although we believe our tax estimates and calculations are reasonable, they have been challenged by taxing authorities in the past. The final determination of any tax audits and litigation may take several years and be materially different from our historical income tax provisions and accruals in our consolidated financial statements. If additional taxes are assessed as a result of an audit, assessment or litigation, there could be a material adverse effect on our financial condition, income tax provision and net income in the affected periods as well as future profitability, cash flows and our ability to pay dividends and service our debt.

If our customers are unable to access credit, they may not be able to purchase our products. In addition, we extend trade credit to customers and the results of our operations may be adversely affected if customers default on these obligations.

Some of our customers require access to credit in order to purchase our products. A lack of available credit to customers, due to global or local economic conditions or for other reasons, could adversely affect demand for, ~~our products~~ and ~~the~~ sales of, our products.

We extend trade credit to our customers primarily in the U.S., ~~and~~UK, ~~throughout~~Mexico ~~the~~and ~~world~~Canada, in some cases for extended periods of time. If these customers are unable to repay the trade credit from us, the results of our operations could be adversely affected. Our customers may be unable to repay the trade credit from us as a result of supply chain disruptions, market conditions in the agricultural sector, adverse weather conditions and increases in prices for other products and inputs that could increase the working capital requirements, indebtedness and other liabilities of our customers. We may not be able to limit our credit and collectability risk or avoid losses.

We are subject to financial assurance requirements and failure to satisfy these requirements could materially affect our business, results of our operations and our financial condition.

In connection with our dispute of tax assessments made by Canadian provincial tax authorities (described in more detail in Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Investments, Liquidity and Capital Resources”, and Part II, Item 8, Note ~~10 of our Consolidated Financial Statements), we are required to post and maintain financial performance bonds~~8. InIncome ~~addition,~~Taxes ~~as part of our business operations, we are required to maintain financial surety or performance bonds with certain of our North American deicing customers~~ and toNote ~~fund reclamation and site cleanup following the ultimate closure of our mines and certain other facilities~~18. WeSubsequent ~~incur~~Event ~~costs to maintain these financial assurance bonds and failure to satisfy these financial assurance requirements could materially affect our business, the results~~ of our ~~operations~~Consolidated ~~and our financial condition.~~


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Financial Statements), we are required to post and maintain financial performance bonds. In addition, as part of our business operations, we are required to maintain financial surety or performance bonds with certain of our North American deicing customers and to fund reclamation and site cleanup following the ultimate closure of our mines and certain other facilities. We incur costs to maintain these financial assurance bonds and failure to satisfy these financial assurance requirements could materially affect our business, the results of our operations and our financial condition.

We ceased paying cash dividends in fiscal 2024; any future cash dividends will be at the discretion of our board of directors and other factors.

On April 22, 2024, the Board of Directors determined not to declare dividends for the foreseeable future in order to align our capital allocation priorities with our corporate focus on accelerating cash flow generation and debt reduction. The payment of any future dividends will be at the discretion of the Board of Directors and will depend upon our financial condition, results of operations, capital requirements, legal requirements, restrictions in our debt agreements and other factors deemed relevant by our Board of Directors. Although our operations are conducted through our subsidiaries, none of our subsidiaries is obligated to make funds available to pay dividends on our common stock. Accordingly, our ability to pay dividends to our stockholders is dependent on the earnings and the distribution of funds from our subsidiaries. Certain agreements governing our indebtedness contain limitations on our ability to pay dividends (including regular annual dividends), as described under “—The agreements governing our indebtedness impose restrictions that may limit our ability to operate our business or require accelerated debt payments.” We cannot provide assurances that the agreements governing our current and future indebtedness will permit us to pay dividends on our common stock.

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Competition, Sales and Pricing Risks

The demand for our products is seasonal.

The demand for our salt, plant nutrition and fire retardant products is seasonal, and the degree of seasonality can change significantly from year to year due to weather conditions, including the number of snow events, rainfall, drought and other factors.

If seasonal demand is greater than we expect, or we experience increased costs and product shortages, and our customers may turn to our competitors for products that they would otherwise have purchased from us. If seasonal demand is less than we expect, we may have excess inventory to be stored (in which case we may incur increased storage costs) or liquidated (in which case the selling price may be below our costs). If prices for our products rapidly decrease, we may be subject to inventory write-downs. Our inventories may also become impaired through obsolescence or the quality may be impaired if our inventories are not stored properly. Low seasonal demand could also lead to increased unit costs.

Anticipated changes in potash prices and customer application rates can have a significant effect on the demand and price for our plant nutrition products.

The demand for our products may be adversely affected by technological advances or the development of new or less costly competing products. For example, the development of substitutes for our plant nutrition products that can more efficiently mix with other agricultural inputs or have more efficient application methods may impact the demand for our products. Many of our products, including sodium chloride, magnesium chloride and SOP, have historically been characterized by a slow pace of technological advances. However, new production methods or sources for our products or the development of substitute or competing products could materially and adversely affect the demand and sales of our products. We also need to continue investing resources in our fire retardant product research and development in order to keep our products competitive.

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diversified, making them less vulnerable to industry downturns and better positioned to pursue new expansion and development opportunities. Our competitive position could suffer if we are unable to expand our operations through investments in new or existing operations or through acquisitions, joint ventures or partnerships.

Inflation could result in higher costs and decreased profitability.

Our business can be affected by inflation, including increases in freight rates, prices for energy and other costs. Sustained inflation could result in higher costs for transportation, energy, materials, supplies and labor. Our efforts to recover inflation-based cost increases from our customers may be hampered as a result of the structure of our contracts and the contract bidding process as well as the competitive industries, economic conditions and countries in which we operate. Accordingly, substantial inflation may result in a material adverse impact on our costs, profitability and financial results.

Increasing costs or a lack of availability of transportation services could have an adverse effect on our ability to deliver products at competitive prices.

Transportation and handling costs are a significant component of our total delivered product cost, particularly for our salt products. The high relative cost of transportation favors producers whose mines or facilities are located near the customers they serve. We contract (directly and, from time to time, through third parties) bulk shipping vessels, barges, trucking and rail services to move our products from our production facilities to distribution outlets and customers. A reduction in the dependability or availability of transportation services, a significant increase in transportation service rates, adverse weather and changes to water levels on the waterways used for our products could impair our ability to deliver our products economically to our customers or expand our markets. For example, when the Mississippi river floods significantly or if water levels are significantly reduced by severe drought conditions (as they were in 2023), barges may be unable to traverse the river system and we may be prevented from timely delivering our salt products to our depots and customers, which could increase costs to deliver our products and adversely impact our ability to fulfill our contracts, resulting in significant contractual penalties and loss of customers.

Significant transportation costs relative to the cost of certain of our products, including our salt products, limit our ability to increase our market share or serve new markets.

Risks associated with our international operations and sales and changes in economic and political environments could adversely affect our business and earnings.

We have significant operations in Canada and the U.K. Our fiscal 2024 sales outside the U.S. were 26% of our total fiscal 2024 sales. Our overall success as a global business depends on our ability to operate successfully in differing economic, political and cultural conditions. Our international operations and sales are subject to numerous risks and uncertainties, including:

•restrictions on our ability to own or operate subsidiaries, make investments or acquire new businesses;

•restrictions on our ability to repatriate earnings from our non-U.S. subsidiaries to the U.S. or the imposition of withholding taxes on remittances and other payments by our subsidiaries;

•political developments, government deadlock, political instability, political activism, terrorist activities, civil unrest and international conflicts (including impacts from the current war in Ukraine); and

•uncertain and varying enforcement of laws and regulations and weak protection of intellectual property rights.

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Conditions in the sectors where we sell products and supply and demand imbalances for competing products can impact the price and demand for our products.

Legal, Regulatory and Compliance Risks

Our operations depend on our rights and governmental authorizations to mine and operate our properties.

We hold numerous environmental and mineral extraction permits, water rights and other permits, licenses and approvals from governmental authorities authorizing operations at each of our facilities. A decision by a governmental agency to revoke, substantially modify, deny or delay renewal of or apply conditions to an existing permit, license or approval could have a material adverse effect on our ability to continue operations at the affected facility and result in significant costs. For example, certain indigenous groups have challenged the Canadian government’s ownership of the land under which our Goderich mine is operated. There can be no assurances that the Canadian government’s ownership will be upheld or that our existing mining and operating permits will not be revoked or otherwise affected. In addition, although we do not engage in fracking, laws and regulations targeting fracking could lead to increased permit requirements and compliance costs for non-fracking operations, including our salt operations, which require permitted wastewater disposal wells. Rulemaking implementing Utah House Bill 513 (now codified as amended Utah Code §65A-6-4) may adversely impact mineral extraction on the Great Salt Lake, including our existing SOP, sodium chloride and magnesium chloride production. We may be impacted by the Voluntary Agreement we entered into with the Utah Division of FFSL, which outlines brine withdrawal caps based on annual lake elevation, discussed further in Item 1., “Business—Environmental, Health and Safety Matters and Other Regulatory Matters”.

Furthermore, many of our facilities are located on land leased from governmental authorities or third parties. Our leases generally require us to continue mining in order to retain the lease, the loss of which could have a material adverse effect on our ability to continue operations at the affected facility and result in significant costs. In some instances, we have received access rights or easements from third parties which allow for a more efficient operation than would exist without the access or easement. Loss of these access rights or easements could have a material adverse effect on us. In addition, many of our facilities are located near existing and proposed third-party industrial operations that could affect our ability to fully extract, or the manner in which we extract, the mineral deposits to which we have mining rights. For example, certain neighboring operations or land uses may require setbacks that could prevent us from mining portions of our mineral reserves or resources or using certain mining methods.

Expansion of our existing operations or production capacity, or preservation of existing rights in some cases, is also predicated upon securing any necessary permits, licenses and approvals.

Unanticipated litigation or investigations, or negative developments in pending litigation or investigations or with respect to other contingencies, could adversely affect us.

We are currently, and may in the future become, subject to litigation, arbitration or other legal proceedings with other parties. Any claim that is successfully asserted against us in these legal proceedings, or others that could be brought against us in the future, may adversely affect our financial condition, results of operations or prospects. For example, on October 21, 2022 we ~~and certain of our former officers, were named as defendants in a putative securities class action lawsuit filed in the United~~

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and certain of our former officers, were named as defendants in a putative securities class action lawsuit filed in the United States District Court for the District of Kansas, alleging that we and such officers made misleading statements damaging shareholders. WeOn ~~intend~~July to30, ~~vigorously~~2025, ~~defend~~the ~~these~~court ~~allegations.~~held Ata ~~this~~hearing ~~time,~~at wewhich ~~are~~it ~~unable~~approved tothe ~~assess~~settlement ~~with~~of ~~any~~$48.0 ~~certainty~~million, ~~what,~~including iffees ~~any,~~and ~~damages~~expenses ~~could~~awarded beto ~~awarded~~lead incounsel ~~this~~and ~~matter~~plaintiffs and our insurers have funded the agreed upon settlement. We are also involved periodically in other reviews, inquiries, investigations and other proceedings initiated by or involving government agencies (including litigation brought by Canadian provincial tax authorities as described in Part II, Item 8, Note 108. toIncome Taxes and Note 18. Subsequent Event of our Consolidated Financial Statements), some of which may result in adverse judgments, settlements, fines, penalties, injunctions or other relief. In these types of matters, it is inherently difficult to determine whether any loss is probable or whether it is possible to estimate the amount of any reasonably possible loss. We cannot predict with certainty if, how or when such proceedings will be resolved or what the eventual judgment, settlement, fine, penalty or other relief, conditions or restrictions, if any, may be. Any eventual judgment, settlement, fine, penalty or other relief, conditions or restrictions could have a material impact on us. For further discussion of pending litigation and governmental proceedings and investigations, see Part II, Item 8, Note 108. Income Taxes, Note 11. Commitments and Contingencies, and Note 1318. toSubsequent Event of our Consolidated Financial Statements.

We are subject to EHS laws and regulations which could become more stringent and adversely affect our business.

Our operations are subject to an evolving set of federal, state, local and foreign EHS laws and regulations. New or proposed EHS regulatory programs, as well as future interpretations and enforcement of existing EHS laws and regulations, may require modification to our facilities, require substantial increases in equipment and operating costs, subject us to fines, penalties or lead to interruptions, modifications or a termination of operations, which could involve significant capital costs, increases in operating costs or other significant impacts.

For example, we are impacted by the Clean Air Act and other EHS laws and regulations that regulate air emissions. These regulatory programs may subject us to fines or penalties or require us to install expensive emissions abatement equipment, modify our operational practices, obtain additional permits or make other expenditures. Our Ogden facility is located in an area expected to be of continued scrutiny by the Environmental Protection Agency and Utah Division of Air Quality with respect to certain air emissions and related issues under the Clean Air Act.

In addition, if new Clean Water Act regulations are adopted or increased compliance obligations are imposed on existing regulations, we could be adversely affected. For example, a significant portion of our salt products are distributed through salt depots owned and operated by third parties. If these depots are required to adopt more stringent stormwater management practices or are subject to increased compliance requirements under existing Clean Water Act regulations, these depots may pass on any increased costs to us, exit the depot business (requiring us to find new depot partners or establish Company-owned depots) or otherwise cause an adverse impact to our ability to deliver salt to our customers. Additionally, governmental agencies could restrict or limit the use of road salt for highway deicing purposes or adopt laws and regulations to address climate change and greenhouse gases, which could have a material impact on us. See Item 1, “Business—Environmental, Health and Safety and Other Regulatory Matters” for more information about EHS laws and regulations affecting us and their potential impact on us.

We could incur significant environmental liabilities with respect to our current, future or former facilities, adjacent or nearby third-party facilities or off-site disposal locations.

Risks of environmental liabilities is inherent in our current and former operations. At many of our past and present facilities, releases and disposals of regulated substances have occurred and could occur in the future, which could require us to investigate, undertake or pay for remediation activities under CERCLA and other similar EHS laws and regulations. The use, handling, disposal and remediation of hazardous substances currently or formerly used by us, or the liabilities arising from past releases of, or exposure to, hazardous substances may result in future expenditures that could materially and adversely affect our financial results, cash flows or financial condition. Our facilities are also subject to laws and regulations which require us to monitor and detect potential environmental hazards and damages. Our procedures and controls may not be sufficient to timely identify and protect against potential environmental damages and related costs.

We record accruals for contingent environmental liabilities when we believe it is probable that we will be responsible, in whole or in part, for environmental investigation, asset retirement obligation or remediation activities and the expenditures for these activities are reasonably estimable. However, the extent and costs of any environmental investigation, asset retirement obligation or remediation activities are inherently uncertain and difficult to estimate and could exceed our expectations, which could materially affect our financial condition and operating results.

~~Additionally,~~24 we2025 ~~previously~~FORM ~~sold a portion of our U.~~10-K. salt mine to a third party, which operates a waste management business. The third party’s business, under governmental permits, is allowed to securely dispose certain hazardous waste at the property they own and they pay us fees for engaging in this activity.

Compliance with import and export requirements, the FCPA and other applicable anti-corruption laws may increase the cost of doing business.

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~~laws~~Additionally, ~~customs~~we ~~laws,~~previously ~~tax~~sold ~~laws~~a ~~and~~portion ~~anti-corruption laws, such as the FCPA, the U.K. Bribery Act and the Canadian Corruption~~ of ~~Foreign~~our ~~Public~~UK ~~Officials~~salt ~~Act.~~mine Weto ~~cannot~~a ~~predict~~third ~~how these or other laws or their interpretation~~party, ~~administration~~which ~~and~~operates ~~enforcement~~a ~~will~~waste ~~change~~management ~~over time~~business. The ~~There~~third ~~can~~party’s ~~be no assurance that our employees~~business, ~~contractors,~~under ~~agents,~~governmental ~~distributors~~permits, ~~customers,~~is ~~payment~~allowed ~~parties or third parties working on our behalf will not take actions in violation of these laws. Any violations of these laws could subject us~~ to ~~civil~~securely ordispose ~~criminal~~certain ~~penalties,~~hazardous ~~including~~waste ~~fines~~at orthe ~~prohibitions~~property onthey ~~our~~own ~~ability to offer our products in one or more countries, debarment from government contracts (~~and ~~termination~~they ofpay ~~existing~~us ~~contracts)~~fees ~~and~~for ~~could~~engaging also materially damage our reputation, brand, international expansion efforts, business and operating results. In addition, changes to trade or anti-corruption laws and regulations could affect our operating practices or impose liability on us in athis ~~manner that could materially and adversely affect our business, financial condition and results of operations~~activity.

Compliance with import and export requirements, the FCPA and other applicable anti-corruption laws may increase the cost of doing business.

Our operations and activities inside and outside the U.S., as well as the shipment of our products across international borders, require us to comply with a number of federal, state, local and foreign laws and regulations, which are complex and increase our cost of doing business. These laws and regulations include import and export requirements, economic sanctions laws, customs laws, tax laws and anti-corruption laws, such as the FCPA, the UK Bribery Act and the Canadian Corruption of Foreign Public Officials Act. We cannot predict how these or other laws or their interpretation, administration and enforcement will change over time. There can be no assurance that our employees, contractors, agents, distributors, customers, payment parties or third parties working on our behalf will not take actions in violation of these laws. Any violations of these laws could subject us to civil or criminal penalties, including fines or prohibitions on our ability to offer our products in one or more countries, debarment from government contracts (and termination of existing contracts) and could also materially damage our reputation, brand, international expansion efforts, business and operating results. In addition, changes to trade or anti-corruption laws and regulations could affect our operating practices or impose liability on us in a manner that could materially and adversely affect our business, financial condition and results of operations.

We are subject to costs and risk associated with a complex regulatory, compliance and legal environment, and we may be adversely affected by changes in laws, industry standards and regulatory requirements.

Our global business is subject to complex requirements of federal, state, local and foreign laws, regulations, treaties and regulatory authorities as well as industry standard-setting authorities. These requirements are subject to change. Changes in the standards and requirements imposed by these laws, regulations, treaties and authorities or adoption of any new laws, regulations or treaties could negatively affect our ability to serve our customers or our business. In the event that we are unable to meet any existing, new or modified standards when adopted, our business could be adversely affected. Some of the federal, state, local and foreign laws and regulations that affect us include those relating to EHS matters; taxes; antitrust and anti-competition laws; data protection and privacy; advertisement and marketing; labor and employment; import, export and anti-corruption; product liability; product registrations and labeling requirements; and intellectual property. We could be adversely affected by the adoption of global minimum taxes as countries implement the Organization for Economic Co-operation and Development’s (“OECD”) Pillar II regime or the side-by-side global minimum tax framework conceptually agreed to amongst the G-7 countries in late June 2025.

If significant import duties were imposed on the salt we import into the U.S. from our Goderich mine, or if we were unable to include the transfer price of such salt in the cost of goods sold for U.S. tax purposes, our financial condition and operating results would be materially and adversely affected. We could also be adversely impacted by changes in tariffs imposed by countries or other trade protection measures, which could decrease our sales in markets where we sell our products. Certain U.S. states have either enacted or proposed legislation that would provide a preference for their agencies or municipalities to use salt mined in the U.S., their home state or selected states. If such legislation is adopted, it could adversely impact the amount of salt sales contracts awarded to us for salt supplied from our Goderich or Cote Blanche mines in the applicable state. Proposed rulemaking implementing Utah House Bill 513 (now codified as amended Utah Code §65A-6-4) may adversely impact mineral extraction on the Great Salt Lake, including our existing SOP, sodium chloride and magnesium chloride production. Failure to comply with applicable laws, regulations or treaties or to comply with any of contracts we have with governmental entities could preclude us from conducting business with governmental entities and lead to penalties, injunctions, civil remedies or fines. For example, our fire retardant products are subject to extensive government regulation, including the USFS qualification process and laws and regulations relating to the award, administration and performance of U.S. government contracts.

We may face significant product liability claims and product recalls, which could harm our business and reputation.

We face exposure to product liability and other claims if our products cause harm, are alleged to have caused harm or have the potential to cause harm to consumers or their property. In addition, our products or products manufactured by our customers using our products could be subject to a product recall as a result of product contamination, our failure to meet product specifications or other causes. For example, our customers use our food-grade salt products in food items they produce, such as cheese and bread, which could be subject to a product recall if our products are contaminated or adulterated. For example, see Part II, Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Product Recall”. Similarly, the use and application of our animal feed and plant nutrition products could result in a product recall if it were alleged that they were contaminated. ~~If our fire retardant products fail to provide the intended protection, they could be subject to a product recall or subject us to liability.~~

A25 ~~product~~2025 ~~recall~~FORM could result in significant losses due to the costs of a recall, the destruction of product inventory and production delays to identify the underlying cause of the recall. We could be held liable for costs related to our customers’ product recall if our products cause the recall or other product liability claims if our products cause harm to our customers or their property. Additionally, a significant product liability case, product recall or failure to meet product specifications could result in adverse publicity, harm to our brand and reputation and significant costs, which could have a material adverse effect on our business and financial performance. 10-K

Our intellectual property may be misappropriated or subject to claims of infringement.

Intellectual property rights, including patents, trademarks, and trade secrets, are a valuable aspect of our business. We attempt to protect our intellectual property rights primarily through a combination of patent, trademark, and trade secret protection. The patent rights that we obtain may not provide meaningful protection to prevent others from selling competitive

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A product recall could result in significant losses due to the costs of a recall, the destruction of product inventory and production delays to identify the underlying cause of the recall. We could be held liable for costs related to our customers’ product recall if our products cause the recall or ~~using~~other ~~similar~~product ~~production~~liability ~~processes~~claims if our products cause harm to our customers or their property. ~~Pending~~Additionally, ~~patent~~a ~~applications~~significant ~~may~~product ~~not~~liability case, product recall or failure to meet product specifications could result in anadverse ~~issued~~publicity, ~~patent.~~harm Ifto weour dobrand ~~receive~~and anreputation ~~issued~~and ~~patent~~significant costs, wewhich ~~cannot~~could ~~guarantee~~have ~~that~~a material adverse effect on our ~~patent~~business ~~rights~~and ~~will~~financial ~~not~~performance. Our insurance coverage may be ~~challenged,~~insufficient ~~invalidated,~~to ~~circumvented,~~cover orall ~~rendered~~losses ~~unenforceable.~~related to product liability claims and product recalls.

Our intellectual property may be misappropriated or subject to claims of infringement.

We also rely on trade secret protection to guard confidential unpatented technology, manufacturing expertise, and technological innovation. Although we generally enter into confidentiality agreements with our employees, third-party consultants and advisors to protect our trade secrets, we cannot guarantee that these agreements provide meaningful protection or that adequate remedies will be available in the event of an unauthorized use or disclosure of our trade secrets.

Our brand names and the goodwill associated therewith are an important part of our business. We seek to register our brand names as trademarks where it makes business sense. Our trademark registrations may not prevent our competitors from using similar brand names. Many of our brand names are registered as trademarks in the U.S. and foreign countries. The laws in certain foreign countries in which we do business do not protect trademark rights to the same extent as U.S. law. As a result, these factors could weaken our competitive advantage with respect to our products, services and brands in foreign jurisdictions, which could adversely affect our financial performance.

Our intellectual property rights may not be upheld if challenged. Such claims, if proven, could materially and adversely affect our business and may lead to the impairment of the amounts recorded for goodwill and other intangible assets. If we are unable to maintain the proprietary nature of our technologies, we may lose any competitive advantage provided by our intellectual property. In addition, although any such claims may ultimately prove to be without merit, the necessary management attention to and legal costs associated with defending our intellectual property rights could be significant.

Strategic and Other Business Risks

We may not successfully implement our strategies.

Our success depends, to a significant extent, on successful implementation of our business strategies, including our back-to-basics strategy, cost savings initiatives, our continuous improvement initiatives, ~~the successful commercialization of Fortress North America’s fire retardants,~~ and any other strategies described in the “Business” section of this ~~report~~Form 10-K. We cannot assure that we will be able to successfully implement our strategies or, if successfully implemented, we may not realize the expected benefits of our strategies.

Although we make investments in product innovation, we cannot be certain that we will be able to develop, obtain or successfully implement new products or technologies on a timely basis or that they will be well-received by our customers. Moreover, our investments in new products and technologies involve certain risks and uncertainties and could disrupt our ongoing business. New investments may not generate sufficient revenue, may incur unanticipated liabilities and may divert our limited resources and distract management from our current operations. We cannot be certain that our ongoing investments in new products and technologies will be successful, will meet our expectations and will not adversely affect our reputation, financial condition and operating results.

Our business is dependent upon personnel, including highly skilled personnel. A labor shortage or the loss of key personnel may have a material adverse effect on our performance.

Our business is dependent on our ability to attract, develop and retain personnel. We may encounter difficulty recruiting sufficient numbers of personnel at acceptable wage and benefit levels due to the competitive labor market. If we are unable to attract, develop and retain the personnel necessary for the efficient operation of our business, this could result in higher costs and decreased productivity and efficiency, which may have a material adverse effect on our performance.

Our business is also dependent on the ability to attract, develop and retain highly skilled personnel. An inability to attract, develop and retain personnel with the necessary skills and experience could result in decreased productivity and efficiency, higher costs, the use of less-qualified personnel and reputational harm, which may have a material adverse effect on our performance.

To26 ~~help~~2025 ~~attract,~~FORM ~~retain and motivate qualified personnel, we use stock~~10-based incentive awards such as restricted stock units and performance stock units. If the value of these stock awards does not appreciate as measured by our common stock price, performance conditions in these awards are not met or if our stock-based compensation otherwise ceases to be viewed as a valuable benefit, our ability to attract, retain and motivate personnel could be weakened, which could harm our business.K

The loss of certain key employees could result in the loss of vital institutional knowledge, experience and expertise, damage critical customer relationships and impact our ability to successfully operate our business and execute our business strategy. We may not be able to find qualified replacements for these key positions and the integration of replacements may be disruptive to our business. In addition, the loss of our key employees who have in-depth knowledge of our mining, manufacturing, engineering or research and development processes could lead to increased competition to the extent that those employees are hired by a competitor and are able to recreate our processes or share our confidential information.

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To help attract, retain and motivate qualified personnel, we offer a compensation package, which may include benefits, short-term incentives, such as annual bonus programs, and long-term incentives, such as stock awards. If our Total Rewards compensation package ceases to be viewed as competitive, for example, the value of long-term awards declines in value as measured by our common stock price, our ability to attract, retain and motivate personnel could be weakened, which could harm our business.

The loss of certain key employees could result in the loss of vital institutional knowledge, experience and expertise, damage critical customer relationships and impact our ability to successfully operate our business and execute our business strategy. We may not be able to find qualified replacements for these key positions and the integration of replacements may be disruptive to our business. In addition, the loss of our key employees who have in-depth knowledge of our mining, manufacturing, engineering processes could lead to increased competition to the extent that those employees are hired by a competitor and are able to recreate our processes or share our confidential information.

If our computer systems, information technology or operations technology are disrupted or compromised, our ability to conduct our business will be adversely impacted.

We rely on computer systems, information technology and operations technology to conduct our business, including cash management, order entry, invoicing, plant operations, vendor payments, ~~employee~~recordkeeping ~~salaries~~of payroll and ~~recordkeeping~~human resource information, inventory and asset management, shipping of products, and communication with employees and customers. We also use our systems to analyze and communicate our operating results and other data to internal and external recipients. While we maintain some of our critical computer and information technology systems, we are also dependent on third parties to provide important computer and information technology services. We continue to make updates and improvements to our enterprise resource planning system, network and other core applications, which could impact substantially all of our key processes. Any implementation issues could have adverse effects on our ability to properly capture, process and report financial transactions, distribute our products, invoice and collect from our customers and pay our vendors and could lead to increased expenditures or operational disruptions.

We are susceptible to cyber-attacks, computer viruses and other technological disruptions, which generally continue to increase due to evolving threats and our ~~expanding~~ information technology footprint. Attackers are also becoming more sophisticated, including due to the increased availability of artificial intelligence (“AI”) tools, and additional vulnerabilities may be introduced from the use of AI by us, our customers or third parties. We have experienced attempts by unauthorized agents to gain access to our computer systems through the internet, e-mail and other access points. To date, none have resulted in any material adverse impact to our business or operations. While we have programs, policies and procedures in place to identify, prevent and detect any unauthorized access, this does not guarantee that we will be able to detect or prevent unauthorized access to our computer systems. In addition, remote work arrangements for our employees could strain our technology resources and introduce operational risks, including heightened cybersecurity risk. Remote working environments may be less secure and more susceptible to hacking attacks, including phishing and other social engineering attempts. These risks have also impacted, and may in the future impact the third parties on which we rely, and security measures employed by these third parties may also prove to be ineffective at countering threats.

A material failure or interruption of access to our computer systems for an extended period of time or the loss of confidential or proprietary data could adversely affect our operations, reputation and regulatory compliance. While we have mitigation and data recovery plans in place, it is possible that significant expenditures, capital investments and time may be required to correct any of these issues. Additional capital investment and expenditures needed to address, prevent, correct or respond to any of these issues may negatively impact our business, financial condition and results of operations.

Climate change and related laws and regulations could adversely affect us.

The potential impact of climate change on our resources, operations, product demand and the needs of our customers remains uncertain. Scientists have proposed that the physical impacts of climate change could include changes in rainfall patterns, water shortages, changing sea levels, changes to the water levels of lakes and other bodies of water, changing storm patterns and intensities and changing temperature levels. These changes could be severe and vary by geographic location. These changes could negatively impact customer demand for our products as well as our costs and ability to produce and distribute our products. For example, prolonged period of mild winter weather could reduce the market for deicing products. Drought conditions could similarly impact demand for our plant nutrition products. Climate change could also lead to disruptions in the production or distribution of our products due to major storm events or prolonged adverse conditions, changing temperature levels, lake or river level fluctuations or flooding from sea level changes. See “—The results of our operations are dependent on ~~and vary due to weather conditions. Additionally, adverse weather conditions or significant changes in weather patterns could adversely affect us.” for more information.~~

In27 ~~addition,~~2025 ~~legislative~~FORM and regulatory measures to address climate change and greenhouse gas emissions (including carbon or emissions taxes) have been enacted and are also in various phases of consideration at both the state and federal level, as well as internationally. These measures could restrict our operations, require us to make capital expenditures to be compliant with these initiatives, increase our costs, impact our ability to compete or negatively impact efforts to obtain permits, licenses and other approvals for existing and new facilities. These measures could also result in increased cost of fuel and other consumables used in our operations or in transporting our products. Our inability to timely respond to the risks posed by climate change and the costs of compliance with climate change laws and regulations could have a material impact on us. 10-K

We may not be able to expand our business through acquisitions and investments, and acquisitions and investments may not perform as expected. We may not successfully integrate acquired businesses and anticipated benefits may not be realized.

In the future, our business strategy may include supplementing organic growth with acquisitions of and investments in complementary businesses. We may not have acquisition or investment opportunities because we may not identify suitable businesses to acquire or invest in, we compete with other potential buyers and investors, we may not have or be able to obtain suitable financing for an acquisition or investment and we may be hindered by competition and regulatory laws. If we cannot make acquisitions or investments, our business growth may be limited.

Acquisitions of new businesses and investments in businesses (including our acquisition of Fortress) may not perform as expected, may lose value, may not positively impact our financial performance and could increase our debt obligations.

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~~Acquisitions~~ and ~~investments~~vary ~~involve~~due ~~significant~~to ~~risks~~weather ~~and~~conditions. ~~uncertainties~~Additionally, ~~including~~adverse ~~diversion~~weather ofconditions ~~management~~or ~~attention,~~significant ~~greater~~changes ~~than~~in ~~expected~~weather ~~liabilities~~patterns ~~and~~could ~~expenses,~~adversely ~~inadequate~~affect ~~return~~us.” onfor ~~capital~~more ~~and unidentified issues not discovered in our due diligence~~information.

In addition, transition risks could include legislative and regulatory measures to address climate change and greenhouse gas emissions (including carbon or emissions taxes) have been enacted and are also in various phases of consideration at both the state and federal level, as well as internationally. These measures could restrict our operations, require us to make capital expenditures to be compliant with these initiatives, increase our costs, impact our ability to compete or negatively impact efforts to obtain permits, licenses and other approvals for existing and new facilities. These measures could also result in increased cost of fuel and other consumables used in our operations or in transporting our products. Our inability to timely respond to the risks posed by climate change and the costs of compliance with climate change laws and regulations could have a material impact on us.

In the future, our business strategy may include supplementing organic growth with acquisitions of and investments in complementary businesses. We may not have acquisition or investment opportunities because we are not able to identify suitable businesses to acquire or invest in, competition with other potential buyers and investors, an inability to obtain suitable financing for an acquisition or investment and restrictions under competition and regulatory laws. If we cannot make acquisitions or investments, our business growth may be limited.

Acquisitions of new businesses and investments in businesses may not perform as expected, may lose value, may not positively impact our financial performance and could increase our debt obligations. Acquisitions and investments involve significant risks and uncertainties, including diversion of management attention, greater than expected liabilities and expenses, inadequate return on capital and unidentified issues not discovered in our due diligence.

The success of any acquisition will also depend on our ability to successfully combine and integrate the acquired business. We may fail to integrate acquired businesses in a timely and efficient manner. The integration process could result in the loss of key employees, higher than expected costs, ongoing diversion of management attention from other strategic opportunities or operational matters, the disruption of our ongoing businesses or increased risk that our internal controls are found to be ineffective.

Outbreaks of contagious disease or similar public health threats could materially and adversely affect our business, financial condition and results of operations.

Outbreaks of contagious disease, including COVID-19, or other adverse public health developments in the U.S. or worldwide could have a material adverse effect on our business, financial condition and results of operations. For example, the emergence and spread of COVID-19 variants could adversely impact our business and results of operations. Outbreaks of contagious disease, including COVID-19, or other adverse public health developments could affect our business in a number of ways, including but not limited to:

•Disruptions or restrictions on our employees’ ability to work effectively due to illness.

•Temporary closures or disruptions at our facilities or the facilities of our customers or suppliers could reduce demand for our products or affect our ability to timely meet our customer’s orders and negatively impact our supply chain.

•Our mining and manufacturing facilities rely on raw materials and components provided by our suppliers. Outbreaks of contagious disease could cause delays or disruptions in our supply chain and we could experience a mining or manufacturing slow-down or seek to obtain alternate sources of supply, which may not be available or may be more expensive.

•The failure of third parties on which we rely, including our suppliers, customers, contractors, commercial banks, transportation service providers and external business partners, to meet their respective obligations to us, or significant disruptions in their ability to do so, which may be caused by their own financial or operational difficulties, could have an adverse impact on our business, financial condition or results of operations.

The impact of contagious disease or other adverse public health developments could also exacerbate other risks discussed elsewhere in this section of this report, any of which could have a material adverse effect on us.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 1C. CYBERSECURITY

Cybersecurity Risk Management and Strategy

Risk Assessment and Management

As digitization and technological advancements continue to accelerate, the landscape of cybersecurity faces new challenges. Compass Minerals remains vigilant in our efforts to minimize risk by safeguarding systems and protecting private business, partner, and customer information. Protection of our digital assets requires strategically focused cybersecurity processes with persistent execution.

We maintain a cybersecurity program employing many components and strategies to mitigate and remediate day-to-day cybersecurity threats and exposures. We approach cybersecurity threats through a cross-functional, multilayered approach, with specific goals of: (i) identifying, preventing and mitigating cybersecurity threats to us; (ii) preserving the confidentiality, security, integrity, and availability of the information that we collect and store to use in our business; (iii) protecting our intellectual property; (iv) maintaining the confidence of our customers, clients and business partners; and (v) providing appropriate public disclosure of cybersecurity risks and incidents when required. Our layered approach to cyber security risk mitigation includes the following:

•Secure architectural solution design of processes and system configuration.

•Assessment and remediation of cybersecurity events with potential impact on business processes.

•Proactive monitoring and mitigation of active exploits through managed services.

•Evolution of the information security governance program.

We28 ~~take~~2025 aFORM ~~risk~~10-based approach to cybersecurity, which begins with the identification and evaluation of cybersecurity risks or threats that could affect our operations, finances, legal or regulatory compliance, and/or reputation. We employ continuous monitoring systems and other technologies and security controls to assist us with the identification of cybersecurity risks and threats. These strategies include, among others, the application, adoption or modification of cybersecurity policies and K

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We take a risk-based approach to cybersecurity, which begins with the identification and evaluation of cybersecurity risks or threats that could affect our operations, finances, legal or regulatory compliance, and/or reputation. We employ continuous monitoring systems and other technologies and security controls to assist us with the identification of cybersecurity risks and threats. These strategies include, among others, the application, adoption or modification of cybersecurity policies and procedures, implementation of administrative, technical, and/or physical controls and employee training, education, and awareness initiatives.

Our cybersecurity risk management includes continuous monitoring of networks and systems for potential signs of suspicious activity. We have deployed managed detection and response ~~services~~ for all corporate production systems (servers, desktops, and laptops). This managed service includes 24x7x365 monitoring, threat hunting, remediation, and escalation to help maintain a secure environment. We also provide mechanisms and training for employees to report to the IT Department any unusual or potentially malicious activity they observe for proper identification and analysis.

We track key performance indicators and cybersecurity metrics to evaluate the efficacy of our cybersecurity controls and practices. ~~Further~~Furthermore, our cybersecurity program is periodically reviewed by senior ~~members of~~ management members and adjusted as needed to maintain the program’s agility and responsiveness as circumstances and technologies evolve, new cybersecurity threats emerge, and regulations change.

Cybersecurity represents a critical component of our overall approach to risk management. Our cybersecurity policies, standards and practices are fully integrated into our enterprise risk management (“ERM”) approach, and cybersecurity risks are among the core enterprise risks that are subject to oversight by our Board of Directors (the “Board”). We separately operate an ERM program to identify, evaluate and manage risks. Cybersecurity risks are evaluated alongside other critical business risks under the ERM program to align cybersecurity efforts with our broader business goals and objectives. We believe that integrating cybersecurity risks into our ERM program fosters a proactive and holistic approach to cybersecurity, which helps safeguard our operations, financial condition, and reputation in an ever-evolving threat landscape. Cybersecurity risks are further considered and evaluated as part of an annual risk assessment performed independently by our internal audit department.

Incident Response

We maintain an incident response policy and program focused upon detecting, managing, documenting, and reporting incidents affecting our systems and data, including those specific to cybersecurity. In the event of a significant cybersecurity incident, we establish an ~~incident~~Incident ~~response~~Response ~~team~~Team (“IRT”) that works in conjunction with our internal crisis management team, subject matter experts, and business stakeholders to identify, contain, eradicate and, if necessary, recover from athe ~~cybersecurity~~ incident. We have built into our incident response program, a review process that gives our disclosure committee real-time access to information to rapidly assess materiality. These efforts may include detecting, identifying, defending against, responding to and, if necessary, recovering from cybersecurity incidents. Incidents that meet certain thresholds are escalated to senior members of management, internal legal advisors, communication specialists and other key stakeholders for additional guidance and action.

Through third parties we are also able to rapidly deploy forensic analysis, legal services, notification, and call center service(s). Our incident response and change management policies and procedures were designed based on guidelines from the National Institute of Standards and Technology (“NIST”) Cybersecurity Framework (“CSF”).

Use of Third Parties

Cybersecurity Service Providers and Third-Party Consultants. Periodically we engage independent cybersecurity consultants, auditors and other third parties to assess and enhance our cybersecurity risk assessment and practices. These third parties conduct independent assessments, penetration testing and vulnerability assessments to identify weaknesses and recommend improvements. When cybersecurity risks are identified, we prioritize mitigation strategies based ~~upon~~on ~~risks’~~the potential impact, likelihood, velocity, and vulnerability of risks, considering both quantitative and qualitative factors. Additionally, we employ several third-party tools and technologies as part of our efforts to enhance cybersecurity functions and monitoring.

Oversight of Third-Party Service Providers. We use third-party service providers to support our operations and many of our ~~technology~~technological initiatives, including third parties that house financial or sensitive information. Our technology acquisition policy and our internal controls framework require us to obtain and review attestation reports regarding these third-party service providers and their sub-service processors or providers and their internal controls, complementary user entity controls and contractual obligations, including those specific to cybersecurity. We evaluate cybersecurity risks associated with our use of third-party service providers, which may include a review of a service provider’s cybersecurity posture or a recommendation of specific mitigation controls. We determine and prioritize service provider risk based on potential threat impact and likelihood and these risk determinations determine the level of due diligence and ongoing compliance monitoring required for each service provider. We have independent validation and assessment capabilities from our cyber insurance provider (Resilience). Each year we select several third-party suppliers for evaluation, analyze resultant reports, and mitigate risks associated with the vendor as needed.

~~Risks~~29 ~~from~~2025 ~~Material~~FORM ~~Cybersecurity Threats~~10-K

As of the date of this report, we have not identified any cybersecurity threats that have materially affected or are reasonably anticipated to have a material effect on the organization. Although we have not previously experienced cybersecurity incidents that are individually, or in the aggregate, material, we have experienced cyberattacks in the past, which we believe have thus far been deflected or mitigated by our preventative, detective, and responsive measures.

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and these risk determinations determine the level of due diligence and ongoing compliance monitoring required for each service provider.

Risks from Material Cybersecurity Threats

As of the date of this Form 10-K, we have not identified any cybersecurity threats that have materially affected or are reasonably anticipated to have a material effect on the organization. Although we have not previously experienced cybersecurity incidents that are individually, or in the aggregate, material, we have experienced cyberattacks in the past, which we believe have thus far been deflected or mitigated by our preventative, detective, and responsive measures.

Cybersecurity Governance

Board Oversight

Our board -level audit committee retains oversight of our ~~cyber~~cybersecurity ~~security~~ program, which is led by our ~~vice~~Vice ~~president~~President of ~~information~~Information ~~technology~~Technology ~~services~~Services. Our senior leadership regularly provides updates on cybersecurity risks and ~~cyber~~cybersecurity ~~security~~ initiatives to both the audit committee and the broader board. The Board is responsible for overseeing management’s assessments of major risks facing the Company and for reviewing options to mitigate these risks. The Board’s oversight of cybersecurity risks occurs at both the Board level and through its Audit Committee.

The Board. The Chief Executive Officer, the Chief Operating Officer, the Chief Financial Officer, other members of ~~senior~~executive management, and other personnel and advisors, as requested by the Board, report on our financial, operating, and commercial strategies, as well as ~~major~~significant related risks, which may include cybersecurity risks, at regularly scheduled meetings of the Board. The Board may request follow-up data and presentations to address any specific concerns or recommendations.

The Audit Committee. The Audit Committee reviews with our management team, including our ~~vice~~Vice ~~president~~President of ~~information~~Information ~~technology~~Technology ~~services~~Services, our cybersecurity frameworks, policies, technologies, programs, opportunities, strategies, and associated risks. These presentations highlight any significant cybersecurity incidents, the cyber threat landscape, cybersecurity program enhancements, cybersecurity risks, related remediation and mitigation activities, security user awareness and reporting training program and any other relevant cybersecurity topics. In addition, members of our Legal Department advise the Audit Committee as needed regarding cybersecurity-related legal matters, including disclosure requirements. Management believes that these reports help to provide the Audit Committee with an informed understanding of our cybersecurity program, risks, and strategies. The Audit Committee may request follow-up data and presentations to address any specific concerns or recommendations. In addition to this periodic reporting, significant cybersecurity risks or threats may also be escalated to the Audit Committee as needed based upon our cyber incident reporting process. The Audit Committee reports regularly to the entire Board and reviews with the Board any major issues that arise at the committee level, which may include cybersecurity risks.

Management’s Role

Our IT Department addresses current and emerging cybersecurity matters. This function is led by our ~~vice~~Vice ~~president~~President of ~~information~~Information ~~technology~~Technology ~~services~~Services, who reports to our Chief ~~Strategy~~Financial Officer, and brings more than 15 years of leadership experience in enterprise technology, digital transformation, and operational risk management. This position oversees the Company’s information technology, cybersecurity, data governance, and enterprise architecture functions and has led multi-year modernization initiatives across infrastructure, core business platforms, and security tooling. The Vice President of Information Technology Services has experience managing cybersecurity frameworks, vulnerability management programs, OT/IT security integration, vendor risk oversight, and incident response preparedness, in addition to a background in leading cross-functional teams, partnering with external security firms, and strengthening organizational controls to reduce cyber, operational, and compliance risks. The Vice President of Information Technology Services holds both a masters degree and a bachelors degree in business administration. Prior to working at Compass Minerals, the Vice President of Information Technology Services held various positions of increasing responsibility within the IT function, including Business Solutions Architect; Manager, Business Solutions; and Director, Business Solutions. The IT Department’s security team, led by our Senior Manager, Cybersecurity, comprise of a cross-functional group ~~composed~~ of members with substantial professional and technical information technology experience, oversees the cybersecurity program to help ensure the confidentiality, integrity and availability of the company’s systems and mitigate day-to-day threats and exposures. It is responsible for measuring and managing cybersecurity risk, including the prevention, detection, mitigation, and remediation of cybersecurity incidents and for implementing cybersecurity policies, programs, procedures and strategies. The security team reports significant cybersecurity incidents to senior management, internal legal advisors, communication specialists and other key stakeholders as required.


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ITEM 2. PROPERTIES

SUMMARY OVERVIEW OF MINING OPERATIONS

Information concerning our mining properties in this Form 10-K has been prepared in accordance with the requirements of subpart 1300 of Regulation S-K. Subpart 1300 of Regulation S-K requires us to disclose our mineral resources, in addition to our mineral reserves, as of the end of our most recently completed fiscal year both in the aggregate and for each of our individually material mining properties. When evaluating materiality for purposes of the disclosure, the Company considered several quantitative metrics including production, sales and capital expenditure data, as well as synergistic and other qualitative information that the Company believes investors would find important to their investing decisions.

As used in this Form 10-K, the terms “mineral resource,” “measured mineral resource,” “indicated mineral resource,” “inferred mineral resource,” “mineral reserve,” “proven mineral reserve” and “probable mineral reserve” are defined and used in accordance with subpart 1300 of Regulation S-K. Under subpart 1300 of Regulation S-K, mineral resources may not be classified as “mineral reserves” unless the determination has been made by a qualified person (“QP”) that the mineral resources can be the basis of an economically viable project. You are specifically cautioned not to assume that any part or all of the mineral deposits (including any mineral resources) in these categories will ever be converted into mineral reserves, as defined by the SEC. See Item 1A, “Risk Factors.”

You are cautioned that, except for that portion of mineral resources classified as mineral reserves, mineral resources do not have demonstrated economic value. Inferred mineral resources are estimates based on limited geological evidence and sampling and have a too high of a degree of uncertainty as to their existence to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability. Estimates of inferred mineral resources may not be converted to a mineral reserve. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. A significant amount of exploration must be completed in order to determine whether an inferred mineral resource may be upgraded to a higher category. Therefore, you are cautioned not to assume that all or any part of an inferred mineral resource exists, that it can be the basis of an economically viable project, or that it will ever be upgraded to a higher category. Likewise, you are cautioned not to assume that all or any part of measured or indicated mineral resources will ever be converted to mineral reserves. See Item 1A, “Risk Factors.”

28The ~~2024~~Company ~~FORM~~has determined that the following properties are individually material mining properties for purposes of subpart 1300 of Regulation S-K: the Ogden facility, the Cote Blanche mine and the Goderich mine. There have been no material changes in the mineral reserves or mineral resources from the last technical report summaries filed for each of the other properties, so the Company is not filing a new technical report summary for any of these properties in connection with this Form 10-K.


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~~determine~~The ~~whether~~following anmap ~~inferred~~shows ~~mineral resource may be upgraded to a higher category. Therefore, you are cautioned not to assume that all or any part of an inferred mineral resource exists, that it can be~~ the ~~basis~~locations of anour ~~economically~~mining ~~viable project~~properties, oras ~~that it will ever be upgraded to a higher category. Likewise, you are cautioned not to assume that all or any part~~ of ~~measured or indicated mineral resources will ever be converted to mineral reserves. See Item 1A~~September 30, ~~“Risk Factors.”~~2025:

~~The~~32 ~~Company~~2025 ~~has~~FORM determined that the following properties are individually material mining properties for purposes of subpart 1300 of Regulation S-K: the Ogden facility, the Cote Blanche mine and the Goderich mine. The Company has terminated its lithium project and is no longer disclosing mineral resources of lithium or lithium carbonate equivalent, so it is not filing a technical report summary for lithium in connection with this Form 10-K. There have been no material changes in the mineral reserves or mineral resources from the last technical report summaries filed for each of the other properties, so the Company is not filing a new technical report summary for any of these properties in connection with this Form 10-K.

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~~The~~As ~~following~~of ~~map~~September 30, ~~shows~~2025, ~~the~~we ~~locations~~had often ~~our~~ mining properties, as ofsummarized ~~September 30,~~in ~~2024~~the table below:

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As of September 30, 2024, we had ten mining properties, as summarized in the table below:

Location

Segment

Use

Stage

United States

Cote Blanche Island, Louisiana

Salt

Rock salt mine

Production

Lyons, Kansas

Salt

Evaporated salt facility

Production

Ogden, Utah

Salt, Plant Nutrition

SOP, solar salt and magnesium chloride facility

Production

Canada

Amherst, Nova Scotia

Salt

Evaporated salt facility

Production

Goderich, Ontario

Salt

Rock salt mine

Production

Goderich, Ontario

Salt

Evaporated salt facility

Production

Unity, Saskatchewan

Salt

Evaporated salt facility

Production

Wynyard, Saskatchewan

Plant Nutrition

SOP facility

Exploration

United Kingdom

Winsford, Cheshire

Salt

Rock salt mine

Production

Chile

Atacama Desert

Salt

N/A

Exploration

We are the sole operator of each of our mining properties and we own all of the ownership interests in our mining operations. With respect to most of our mineral properties, we own the land and surface rights and have entered into lease agreements with respect to the mineral rights. Our mineral leases have varying terms. Some will expire after a set term of years, while others continue indefinitely. Many of these leases provide for a royalty payment to the lessor based on a specific amount per ton of minerals extracted or as a percentage of revenue. In addition, we own a number of properties and are party to non-mining leases that permit us to perform activities that are ancillary to our mining operations, such as surface use leases for storage at depots and warehouse leases. We believe that all of our leases were entered into at market terms.

We hold numerous environmental and mineral extraction permits, water rights and other permits, licenses and approvals from governmental authorities authorizing operations at each of our facilities. With respect to each facility at which we produce salt, brine or SOP, permits, licenses and approvals are obtained as needed in the normal course of business based on our mine plans and federal, state, provincial and local regulatory provisions regarding mine permitting and licensing. Based on our historical permitting experience, we expect to be able to continue to obtain necessary mining permits and approvals to support historical rates of production.

The three processing methods we use to produce salt and SOP at our production-stage properties are as follows:

•Underground Rock Salt Mining - We produce most of the salt we sell through underground mining. In North America, we use a combination of continuous mining and drill and blast techniques. At our Winsford, Cheshire, ~~U.K.~~UK, mine, we utilize continuous mining techniques. Mining machinery moves salt from the salt face to conveyor belts, which transport the salt to the mill center where it is crushed and screened. It is then hoisted to the surface where the processed salt is loaded onto shipping vessels, railcars or trucks. The primary power sources for each of our rock salt mines are electricity and diesel fuel. Rock salt is sold in our highway deicing product lines and for numerous applications in our consumer and industrial product lines.

•Mechanical Evaporation - Mechanical evaporation involves creating salt-saturated brine from brine wells in underground salt deposits and subjecting this salt-saturated brine to vacuum pressure and heat to precipitate and crystallize salt. The primary power sources used for this process are natural gas and electricity. The resulting product has a high purity and uniform physical shape. Mechanically-evaporated salt is primarily sold through our consumer and industrial salt product lines.

•Solar Evaporation - For a description of the solar evaporation process, see “—Ogden Facility” below.

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Our current estimated production capacity is approximately 1615.25 million tons of salt and 360,000 tons of SOP per year. The following table shows the estimated annual production capacity and type of salt or other mineral produced at each of our owned or leased processing locations as of September 30, ~~2024~~2025:


Location	Annual Production Capacity(1) (tons)	Product Type
North America
Goderich, Ontario, Mine	8.0 million	Rock Salt
Cote Blanche, Louisiana, Mine	2.9 million	Rock Salt
Ogden, Utah, Plant:
Salt(2)	1.5 million	Solar Salt
Magnesium Chloride(3)	750,000	Magnesium Chloride
SOP(4)	320,000	SOP
Lyons, Kansas, Plant	450,000	Mechanically-Evaporated Salt
Unity, Saskatchewan, Plant	140,000	Mechanically-Evaporated Salt
Goderich, Ontario, Plant	140,000	Mechanically-Evaporated Salt
Amherst, Nova Scotia, Plant	135,000	Mechanically-Evaporated Salt
Wynyard, Saskatchewan, Plant	40,000	SOP
United Kingdom
Winsford, Cheshire, Mine	2.2 million	Rock Salt

(1)Annual production capacity is our estimate of the tons that could be produced based on design capacity, assuming optimization of our operations, including our facilities, equipment and workforce. Incremental equipment, labor or other costs may be required to achieve these production capacity estimates. As we continue our efforts to optimize and refine our production methods, we will update our estimates if necessary.

(2)Solar salts deposited annually substantially exceed the amount converted into finished products. The amount presented here represents an approximate average amount produced based on recent market demand.

(3)The magnesium chloride amount includes both brine and flake.

(4)The annual SOP production capacity at our Ogden facility during normal weather and pond chemistry conditions, which includes amounts produced from both solar-pond based feedstock and supplemental KCl feedstock when economically feasible.

Actual annual salt, magnesium chloride and SOP production volume levels may vary from the annual production capacity shown in the table above due to a number of factors, including variations in the winter weather conditions which impact demand for highway and consumer deicing products, the quality of the reserves and the nature of the geologic formation that we are mining at a particular time, unplanned downtime due to safety concerns, incidents and mechanical failures, and other operating conditions.

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The following table shows production by product at our owned and leased production locations, in tons:

Fiscal Year Ended

September 30, 2024

September 30, 2023

September 30, 2022

September 30, 2025

September 30, 2024

September 30, 2023

Salt(1)

Cote Blanche mine

1,~~837~~783,~~389~~065

1,~~965~~837,~~257~~389

1,~~944~~965,~~722~~257

Goderich mine

4,~~300~~310,~~103~~462

64,~~034~~300,~~204~~103

6,~~305~~034,~~067~~204

Ogden facility(2)

~~901~~947,~~267~~909

1901,~~177,465~~267

1,~~165~~177,~~767~~465

Other

1,~~392~~529,~~416~~700

1,~~652~~392,~~512~~416

1,~~686~~652,~~668~~512

Total Salt

8,~~431~~571,~~175~~136

108,~~829~~431,~~438~~175

1110,~~102~~829,~~224~~438

SOP

Ogden facility

~~226~~257,~~313~~185

~~238~~226,~~428~~313

~~245~~238,~~165~~428

Other

3037,~~272~~762

3730,~~805~~272

4137,~~486~~805

Total SOP

~~256~~294,~~585~~947

~~276~~256,~~233~~585

~~286~~276,~~651~~233

Magnesium Chloride

Ogden facility(2)

~~671~~660,~~486~~410

~~731~~671,~~490~~486

~~686~~731,~~213~~490

Total Magnesium Chloride

~~671~~660,~~486~~410

~~731~~671,~~490~~486

~~686~~731,~~213~~490

(1)Excludes solar salt harvested at our Ogden facility that is not converted into finished product and salt processed at our packaging facilities.

(2)Fiscal year 2023 ~~and 2022~~ production tons are less than our reserve reduction due to process timing of extracting tons to producing finished product. See Ogden Facility below for additional information regarding our sodium, sodium chloride, magnesium and magnesium chloride reserve estimates at the Ogden facility.

Our production facilities have access to vast mineral deposits. At all of our production locations, we estimate the recoverable reserves to last at least several more decades at current production rates and capacities, although additional capital resources and developmental spending may be required. Our rights to extract those minerals may be contractually limited by geographic boundaries or time. We believe that we will be able to continue extending these agreements, as we have in the past, at commercially reasonable terms without incurring substantial costs or material modifications to the existing lease terms and conditions, thereby allowing us to fully utilize our existing mineral rights.

Our underground mines in Canada (Goderich, Ontario), the U.S. (Cote Blanche, Louisiana) and the ~~U.K.~~UK (Winsford, Cheshire) make up 85% of our salt production capacity as of September 30, ~~2024~~2025. Each of these mines is operated with modern mining equipment and utilizes subsurface improvements, such as vertical shaft lift systems, milling and crushing facilities, maintenance and repair shops and extensive raw materials handling systems.

In 2012, we acquired mining rights to approximately 100 million tons of salt resources in the Chilean Atacama Desert. This resource estimate is based upon an initial assessment. A feasibility study would be completed before we decide whether to proceed with the development of this project to ensure the salt resources can be converted into reserves. The development of this project would require significant infrastructure to establish extraction and logistics capabilities. As of September 30, ~~2024~~2025 our investment in these rights totaled $8.5 million.

Summary of Mineral Resources and Reserves

Summaries of our mineral resources and reserves at the end of fiscal ~~2024~~2025 are set forth in Tables 1 and 2. Each mineral resource and reserve estimate is based on a reasonable and justifiable prices selected by a qualified person, as indicated in the notes to the tables below. These price assumptions provide a reasonable basis for establishing the prospects of economic extraction for mineral resources and for establishing that the project is economically viable for reserves.

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Table 1. Summary Mineral Resources at September 30, ~~2024~~2025

Measured Mineral Resources (tons)(1)

Indicated Mineral Resources (tons)(1)

Measured + Indicated Mineral Resources (tons)(1)

Inferred Mineral Resources (tons)(1)

Salt(2)(3)

United States

Cote Blanche mine

3127,~~022~~635,~~341~~059

629,032,729

~~660~~656,~~055~~667,~~070~~788

163,767,364

Ogden facility(4)

—

2,~~139~~138,~~215~~162,~~607~~374

—

Lyons

~~137~~136,~~214~~372,~~766~~326

~~193~~231,~~979~~579,000

~~331~~367,~~193~~951,~~766~~326

—

Total United States

~~168~~164,~~237~~007,~~107~~385

2,~~962~~998,~~227~~774,~~336~~103

3,~~130~~162,~~464~~781,~~443~~488

163,767,364

Canada

Goderich mine

—

1,~~441~~430,~~611~~188,~~742~~004

148,200,000

Goderich plant

6669,~~550~~494,~~160~~610

41,700,000

~~108~~111,~~250~~194,~~160~~610

—

Amherst

—

408,~~794~~636,~~258~~916

—

Unity

—

251,~~873~~676,~~143~~433

—

Total Canada

6669,~~550~~494,~~160~~610

2,~~143~~132,~~979~~201,~~143~~353

2,~~210~~201,~~529~~695,~~303~~963

148,200,000

United Kingdom

Winsford

4241,~~896~~333,~~918~~687

7,730,000

5049,~~626~~063,~~918~~687

—

Total United Kingdom

4241,~~896~~333,~~918~~687

7,730,000

5049,~~626~~063,~~918~~687

—

Chile

Atacama Desert property

—

102,531,129

—

Total Chile

—

102,531,129

—

Total Salt

~~277~~274,~~684~~835,~~185~~682

5,~~216~~241,~~467~~236,~~608~~585

5,~~494~~516,~~151~~072,~~793~~267

311,967,364

SOP(5)(6)

United States

Ogden facility(7)

—

89,~~461~~182,~~892~~949

—

Total United States

—

89,~~461~~182,~~892~~949

—

Canada

Wynyard(8)

—

Total Canada

—

Total SOP

—

89,~~461~~182,~~892~~949

—

Magnesium Chloride(9)(10)

United States

Ogden facility(11)

—

~~358~~357,~~632~~898,~~573~~785

—

Total United States

—

~~358~~357,~~632~~898,~~573~~785

—

Total Magnesium Chloride

—

~~358~~357,~~632~~898,~~573~~785

—

(1)Mineral resources are reported in situ. Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that all or any part of the mineral resources will be converted into mineral reserves upon application of modifying factors.

(2)Based on an average sodium chloride grade of 97,350 milligrams per liter (“mg/L”) in the north arm of the Great Salt Lake and 46,300 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm. Grades of in-situ sodium chloride range from 75% at our Lyons facility to 98% at the Goderich mine. Although the actual sodium chloride grade at our underground mines is less than 100%, it is not considered in the resource, as the final saleable product is the in situ product, as-present (i.e., the saleable product includes any impurities present in the in situ rock).

(3)There are multiple saleable products based on salt quality from the underground mining operations (rock salt for road deicing and chemical grade salt). For simplicity, all sales are assumed at the lower value (and higher tonnage) product, rock salt, and are based on pricing data based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for rock salt for road deicing of $6463.4065 per ton to $94107.9828 per ton. Sales prices are projected to increase to approximately $319.63 per ton to $1,204.66 per ton for rock salt for road deicing through the current expected end of mine life.

~~(4)The~~36 ~~Company~~2025 ~~does~~FORM not have exclusive access to mineral resources in the lake and other existing operations, including those run by US Magnesium, Morton Salt and Cargill, also extract dissolved mineral from the lake (all in the south arm).10-K

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(4)The Company does not have exclusive access to mineral resources in the lake and other existing operations, including those run by US Magnesium, Morton Salt and Cargill, also extract dissolved mineral from the lake (all in the south arm).

(5)With respect to the Ogden facility, based on an average potassium grade of 7,320 mg/L in the north arm of the Great Salt Lake and 3,060 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

(6)With respect to the Ogden facility, based on pricing data based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for SOP of $~~659~~672.9627 per ton. Sales prices are projected to increase to approximately $8,529 per ton through the current expected end of mine life.

(7)The Company does not have exclusive access to mineral resources in the lake, and other existing operations, including those run by US Magnesium and Cargill, also extract dissolved mineral from the lake (all in the south arm).

(8)No resources or reserves have been estimated for the Wynyard facility since the production process relies on the import of KCl as a source of potassium from external sources, with supplemental potassium from a relatively dilute concentration of potassium (approximately 0.05%) from Big Quill Lake.

(9)Based on an average magnesium chloride grade of 11,150 mg/L in the north arm of the Great Salt Lake and 4,790 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

(10)Based on pricing data based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for magnesium chloride of $7485.4649 per ton. Sales prices are projected to increase to approximately $1,~~100~~238.3959 per ton through the current expected end of mine life.

(11)The Company does not have exclusive access to mineral resources in the lake, and other existing operations, including those run by US Magnesium, also extract dissolved mineral from the lake (in the south arm).

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Table 2. Summary Mineral Reserves at September 30, ~~2024~~2025

Proven Mineral Reserves (tons)(1)

Probable Mineral Reserves (tons)(1)

Total Mineral Reserves (tons)(1)

Salt(2)(3)

United States

Cote Blanche mine

1715,~~522~~739,~~245~~180

236,547,378

~~254~~252,~~069~~286,~~623~~558

Ogden facility

—

~~157~~156,~~524~~576,~~046~~137

Lyons

—

1817,~~269~~932,~~542~~566

Total United States

1715,~~522~~739,~~245~~180

~~412~~411,~~340~~056,~~966~~081

~~429~~426,~~863~~795,~~211~~261

Canada

Goderich mine

—

~~453~~449,~~390~~080,~~625~~163

Goderich plant

883,~~535~~140,563

5,700,000

58,~~788~~840,~~535~~563

Amherst

—

5,~~169~~054,~~347~~487

Unity

~~231~~113,~~294~~268

24,179,074

24,~~410~~292,~~368~~342

Total Canada

~~319~~3,~~829~~253,831

~~488~~484,~~439~~013,~~046~~724

~~488~~487,~~758~~267,~~875~~555

United Kingdom

Winsford

2019,~~317~~505,~~997~~117

3,710,000

2423,~~027~~215,~~997~~117

Total United Kingdom

2019,~~317~~505,~~997~~117

3,710,000

2423,~~027~~215,~~997~~117

Chile

Atacama Desert property

—

Total Chile

—

Total Salt

38,~~160~~498,~~071~~128

~~904~~898,~~490~~779,~~012~~805

~~942~~937,~~650~~277,~~083~~933

SOP(4)(5)

United States

Ogden facility

—

4544,~~058~~801,~~239~~054

Total United States

—

4544,~~058~~801,~~239~~054

Canada

Wynyard(6)

—

Total Canada

—

Total SOP

—

4544,~~058~~801,~~239~~054

Magnesium Chloride(7)(8)

United States

Ogden facility

—

9392,~~349~~688,~~316~~906

Total United States

—

9392,~~349~~688,~~316~~906

Total Magnesium Chloride

—

9392,~~349~~688,~~316~~906

(1)Ore reserves are as recovered, saleable product.

(2)Based on an average sodium chloride grade of 97,350 mg/L in the north arm of the Great Salt Lake and 46,300 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm. Grades of in-situ sodium chloride range from 75% at our Lyons facility to 98% at the Goderich mine. Although the actual sodium chloride grade at our underground mines is less than 100%, it is not considered in the reserve, as the final saleable product is the in situ product, as-present (i.e., the saleable product includes any impurities present in the in situ rock).

(4)With respect to the Ogden facility, based on an average potassium grade of 7,320 mg/L in the north arm of the Great Salt Lake and 3,060 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

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(5)With respect to the Ogden facility, based on pricing data based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for SOP of $~~659~~672.9627 per ton. Sales prices are projected to increase to approximately $8,529 per ton through the current expected end of mine life.

(6)No resources or reserves have been estimated for the Wynyard facility since the production process relies on the import of KCl as a source of potassium from external sources, with supplemental potassium from a relatively dilute concentration of potassium (approximately 0.05%) from Big Quill Lake.

(7)Based on an average magnesium chloride grade of 11,150 mg/L in the north arm of the Great Salt Lake and 4,790 mg/L in the south arm of the Great Salt Lake. Reported concentrations for the Great Salt Lake assume an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

(8)Based on pricing data based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for magnesium chloride of $7485.4649 per ton. Sales prices are projected to increase to approximately $1,~~100~~238.3959 per ton through the current expected end of mine life.

Our mineral resource and reserve estimates were prepared by a QP and have a basis in periodic, historical reserve studies completed by third-party geological engineering firms. Our mineral resource and reserve estimates and the third-party reserve studies are based on many factors, including the area and volume covered by our mining rights, assumptions regarding our extraction rates based upon an expectation of operating the mines on a long-term basis and the quality of in-place reserves. Established criteria for inferred, indicated and measured resources and proven and probable reserves are primarily applicable to mining deposits of discontinuous metal, where both the presence of ore and its variable grade need to be precisely identified. However, the massive continuous nature of evaporative deposits, such as salt deposits, requires proportionately less data for the same degree of confidence in mineral resources and reserves, both in terms of quantity and quality.

OGDEN FACILITY

The Ogden facility is a production stage property that separates and processes potassium, sodium and magnesium salts from brine sourced from the Great Salt Lake in Utah. The primary product currently produced at the Ogden facility is SOP (which is a potassium-rich salt used as plant fertilizer), with coproduct production of sodium chloride (which is used for highway deicing and chemical applications) and magnesium chloride (which is used in deicing, dust control and unpaved road surface stabilization applications and is an ingredient in our fire retardant products). The Company has also identified a lithium ~~resource~~deposit at the Ogden facility, but has recently indefinitely suspended its plans to add lithium salt as a coproduct to SOP production. The Ogden facility relies upon solar evaporation to concentrate brine extracted from the north arm of the Great Salt Lake and precipitate the salts into a series of large evaporation ponds located on the east and west sides of the lake, referred to as the east ponds and the west ponds, respectively, prior to harvesting and processing at its related plant (the “Ogden plant”). Maps of the Ogden facility are shown in Figures 1 and 2.

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Figure 1. Ogden Facility Property Location Map

Ogden Facility Property Location Map.jpg

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Figure 2. Locations of East and West Ponds Relative to the Ogden Plant and the Great Salt Lake

The Great Salt Lake is the largest saltwater lake in the western hemisphere, and the fourth largest terminal lake in the world, covering approximately 1,700 square miles. It is also one of the most saline lakes in the world, with a chemical composition very similar to the world’s oceans. Salinity throughout the Great Salt Lake is governed by lake level, freshwater inflows, precipitation and re-solution of salt, mineral extraction, and circulation and constriction between bays of the lake.

The infrastructure associated with the Ogden facility, including the Ogden plant, is located on the shores of the Great Salt Lake in Box Elder and Weber Counties in the State of Utah. The Ogden plant is located at the approximate coordinates of 41˚16’51” North and 112˚13’53” West on the east side of the lake approximately 15 miles (by road) to the west of Ogden, Utah, and 50 miles (by road) to the northwest of Salt Lake City, Utah. The east ponds are located adjacent (to the north and west) to the Ogden plant in Bear River Bay. The west ponds are located on the opposite side of the Great Salt Lake (due west) in Clyman and Gunnison Bays. Access to the Ogden facility is via Ogden, Utah, and its vicinity on paved two-lane roads. From Salt Lake City, Utah, located 40 miles to the south, Ogden is accessible via Interstate Highway 15. Commercial air travel is accessible from Salt Lake City. The area population provides a more than adequate base for staffing the Ogden facility, with a pool of talent for both trades and technical management. The Ogden facility is connected to the local municipal water distribution system, Weber Basin Water Conservation District. The Ogden facility is also connected to the local electrical and natural gas distribution systems provided by Rocky Mountain Power and Dominion Energy, respectively, and houses an existing substation that services the operations at the east ponds. Rail access is provided by Union Pacific Railroad on an existing siding at the Ogden plant.

The Ogden facility is located on approximately 108,749 acres of land, of which approximately 7,434.16 acres are owned by the Company. The Great Salt Lake and minerals associated with it are owned by the State of Utah. The Company is able to extract and produce salts from the lake by rights derived from a combination of: (i) lakebed lease agreements (the “Lakebed Leases”) with the Utah Department of Natural Resources, Division of Forestry, Fire and State Lands (the “Utah FFSL”); (ii) one lease for upland evaporation ponds (the “Upland Pond Lease”) with the State of Utah School and Institutional Trust Lands Administration (the “Utah SITLA”); (iii) seven non-solar leases and easements; (iv) water rights for consumption of brines and freshwater (the “Water Rights”) through the Utah Department of Natural Resources, Division of Water Rights; (v) a large mine operation mineral extraction permit (GSL Mine M/057/0002) (the “Mineral Extraction Permit”) through the Utah Department of Natural Resources, Division of Oil, Gas and Mining (the “Utah DOGM”); and (vi) a royalty agreement for extraction of all ~~mineral salts, dated September 1, 1962 (as amended from time to time, the “Royalty Agreement”), with the Utah State Land Board.~~

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mineral salts, dated September 1, 1962 (as amended from time to time, the “Royalty Agreement”), with the Utah State Land Board.

Leasable areas for mineral extraction on the Great Salt Lake lakebed are identified in the Great Salt Lake Comprehensive Management Plan (the “GSL Plan”), which is managed by the Utah FFSL. The GSL Plan is updated approximately every ten years, or when there are major changes to the Great Salt Lake environment and setting. A party interested in leasing lakebed for mineral extraction may nominate an area within the area designated by the GSL Plan as leasable, at which time, the Utah FFSL will issue public notice of lease nomination, conduct an environmental assessment on the nominated lease area, and ultimately consider approval of the lease nomination. This process was followed historically in the acquisition of existing Lakebed Leases held by the Company for the Ogden facility.

The Lakebed Leases and Upland Pond Lease provides the Company the right to develop mineral extraction and processing facilities on the shore of the Great Salt Lake. The Lakebed Leases and Upland Pond Lease were issued between 1965 and 2022 and amended and restated in 2024, covering a total lease area of approximately 100,068 acres among seven active leases, though not all are currently utilized.

Each of the Lakebed Leases, have an initial term (Initial term) of 20 years beginning in October 2024 and shall be extended for successive twenty years terms (Extended Terms) provided that Compass Minerals has fully performed all of its obligations under each renewing lease. FFSL may cancel the renewal of any Lease by providing written notice to Compass Minerals at least ninety (90) days prior to the expiration of the Initial Term or any Extended Term (“FFSL Notice Date”), provided however, that FFSL’s right to cancel a Lease renewal term shall be limited to the existence, at the time of the FFSL Notice Date, of a material default or breach of the terms of the applicable Lease. Most of the Lakebed Leases provide the State of Utah with the opportunity to periodically adjust the lease’s terms, except for the royalties to be paid. These readjustment opportunities occur at intervals ranging from five to 20 years. In the past, these periodic readjustments have not materially hindered the business.

Pursuant to each of the Lakebed Leases, the Company is obligated to pay rent at rates ranging from $0.50 to $2.00 per acre per year, and some leases have a minimum rent of $10,000 per year. The rent paid pursuant to each lease is credited against the Company’s royalty obligations pursuant to the Royalty Agreement (as described further below).

The Upland Pond Lease consists of a single Special Use Lease Agreement (“SULA”) 1971, consisting of 37,181 acres, which was acquired on July 14, 2022. The rent for SULA 1971 is $427,584 per year. SULA 1971 is a 50-year lease expiring on June 30, 2072. SULA 1971 consists of former SULA 1186, which was acquired in May 1999, and SULA 1267, which was acquired from Solar Resources International in 2013, as well as an additional 13,833 acres. The Upland Pond Lease allows for the construction and operation of evaporation ponds on the subject properties. The Upland Pond Lease does not impose any material conditions on the Company’s retention of the property except for payment of rent.

The Company also holds seven non-solar leases and easements granted by Utah FFSL or Utah SITLA covering approximately 1,258 acres. Two of these are material to the operation of the Ogden facility, Behrens Trench Easement 400-00313 and PS-113 Easement SOV002-0400. The Company paid a one-time fee of $42,514 for Behrens Trench Easement 400-00313, which expires in June 2051. The Company paid a one-time fee of $27,273 for PS-113 Easement SOV002-0400, which does not expire. The Company also has a lease indenture for a brine canal with the Union Pacific Railroad, dated April 13, 1967, on Promontory Point. The indenture automatically renews with payment, which is $595.72 annually.

The Water Rights are procured by application to the Utah Department of Natural Resources, Division of Water Rights, which reviews the application and evaluates the proposed nature of use, place of use, and point of diversion in light of availability of water pursuant to hydrology and/or prior claims relative to the available water, and whether the proposed use would impair existing water right holders. The application is posted for public review and comment, and the State Engineer evaluates the merits of the application and either approves or denies the application, sometimes with modifications or conditions on future use. The Water Rights control the actual extraction of minerals from the Great Salt Lake and dictate the amount of brine that can be pumped from the lake on an annual basis. The Company has 156,000 acre-feet extraction rights from the north arm of the Great Salt Lake under five Water Rights, on which it relies for its current production. As a limit on the volume of brine that can be pumped from the lake in a year, the Water Rights effectively cap the aggregate production of salt that is possible in any year. The Company has certificated the Water Rights that contribute to the 156,000 acre feet of extraction rights, meaning that demonstration of actual use in order to retain the right in perpetuity has been approved and authorized. The Company may be impacted by the Voluntary Agreement with the Utah Division of FFSL, which outlines brine withdrawal caps based on annual lake elevation, discussed further in Item 1., “Business—Environmental, Health and Safety Matters and Other Regulatory Matters”.

~~The~~42 ~~Mineral~~2025 ~~Extraction~~FORM Permit (GSL Mine M/057/0002) was granted by the Utah DOGM. The Mineral Extraction Permit enables extraction of brine from the Great Salt Lake and ultimate mineral extraction from the brine. The Mineral Extraction Permit also enables all lake extraction, pond operations, and plant and processing operations conducted by the Company at the Ogden facility. The Mineral Extraction Permit is supported by a reclamation plan that documents all aspects of current operations and mandates certain closure and reclamation requirements in accordance with Utah Rule R64710-4-104. Financial assurance for the ultimate reclamation of facilities is documented in the reclamation plan, and security for costs that will be incurred to execute site closure is provided by a third-party insurer to the State of Utah in the form of a surety bond. The total future reclamation obligation is estimated to be $4.36 million. K

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~~costs~~The Mineral Extraction Permit (GSL Mine M/057/0002) ~~per~~was ~~pound~~granted ofby ~~salts~~the ~~produced~~Utah DOGM. ~~Under~~The Mineral Extraction Permit enables extraction of brine from the ~~Royalty~~Great ~~Agreement~~Salt Lake and ultimate mineral extraction from the brine. The Mineral Extraction Permit also enables all lake extraction, pond operations, and plant and processing operations conducted by the ~~current~~Company ~~royalty~~at ~~rate~~the ~~for~~Ogden ~~SOP~~facility. The Mineral Extraction Permit is supported by a reclamation plan that documents all aspects of current operations and mandates certain closure and reclamation requirements in accordance with Utah Rule R647-4-104.8% Financial assurance for the ultimate reclamation of ~~gross~~facilities ~~revenues,~~is documented in the ~~current~~reclamation ~~royalty~~plan, ~~rate~~and security for ~~magnesium~~costs ~~chloride~~that will be incurred to execute site closure is 5%provided ofby ~~gross~~a ~~revenues,~~third-party ~~and~~insurer to the ~~current~~State ~~royalty~~of ~~rate~~Utah ~~for~~in ~~sodium~~the ~~chloride~~form isof $0a surety bond.~~50/ton~~ ~~times~~The ~~the~~total ~~Producer~~future ~~Price~~reclamation ~~Index~~obligation is estimated to be $4.36 million.

Pursuant to the Royalty Agreement, the Company has rights to all salts from the Great Salt Lake, and in exchange, the Company pays a royalty to the State of Utah based on net revenues (gross revenue net of sales taxes and shipping and handling costs) per pound of salts produced. Under the Royalty Agreement, the current royalty rate for SOP is 4.8% of gross revenues, the current royalty rate for magnesium chloride is 5% of gross revenues, and the current royalty rate for sodium chloride is $0.50/ton times the Producer Price Index.

The Ogden facility is the largest SOP production site in the western hemisphere, and one of only four large-scale solar brine evaporation operations for SOP in the world. We believe the Ogden facility has the capability to produce 320,000 tons of SOP, including amounts produced with both solar-pond based feedstock and supplemental KCl feedstock when economically feasible, approximately 750,000 tons of magnesium chloride and 1.5 million tons of sodium chloride annually during normal weather and pond chemistry conditions. These recoverable minerals exist in vast quantities in the Great Salt Lake.

Solar evaporation is used in areas of the world where high-salinity brine is available and weather conditions provide for a high natural evaporation rate. Mineral-rich lake water, or brine, from the Great Salt Lake is drawn into the solar evaporation ponds. The brine moves through a series of solar evaporation ponds over a two- to three-year production cycle. As the water evaporates and the mineral concentration increases, some of those minerals naturally precipitate out of the brine and are deposited on the pond floors. These deposits provide the minerals necessary for processing into SOP, solar salt and magnesium chloride. The evaporation process is dependent upon sufficient lake brine levels and hot, arid summer weather conditions. The potassium-bearing salts are mechanically harvested out of the solar evaporation ponds and refined to high-purity SOP through flotation, crystallization and compaction at the Ogden plant. After sodium chloride and potassium-rich salts precipitate from brine, a concentrated magnesium chloride brine solution remains, which becomes the raw material used to produce several magnesium chloride products.

Operations have been ongoing at the Ogden facility since the late 1960s, with commercial production starting in 1970. Lithium Corporation of America (“Lithcoa”), separately, and then in a partnership with a wholly owned subsidiary of Salzdetfurth, A.G., carried out initial exploration and development activities between 1963 and 1966. In 1967, Gulf Resources and Minerals Co., or Gulf Resources, acquired Lithcoa, and in 1973, acquired Salzdetfurth, A.G.’s (then known as Kaliund Salz A.G.) partnership interest. Gulf Resources made significant capital expenditures in the early 1980s to protect the evaporation pond system at the Ogden facility from the rising levels of the Great Salt Lake. On May 5, 1984, a northern dike of the system breached, resulting in severe flooding and damage to about 85% of the pond complex. The breach resulted in physical damage to dikes, pond floors, bridges, pump stations, and other structures. In addition, brine inventories were diluted, making them unusable for producing SOP. During the next five years, Gulf Resources pumped the water from its solar ponds, reconstructed peripheral and interior dikes and roads, replaced pump stations, and laid down new salt floors in order to restart its operation at the Ogden facility. In 1993, D.G. Harris & Associates acquired the Ogden facility, and in 1994, constructed the west ponds, which are connected to the east ponds by a 21-mile, open, underwater canal called the Behrens Trench, which was dredged in the lakebed from the west ponds’ outlet to a pump station near the east ponds. Ownership of the Ogden facility was transferred in 1997 to IMC Global (“IMC”), following its acquisition of Harris Chemical Group (part of D.G. Harris & Associates). IMC sold a majority of its salt operations, including the Ogden facility, to Apollo Management V, L.P. through an entity called Compass Minerals Group in 2001. Following a leveraged recapitalization, the company now known as Compass Minerals International, Inc. completed an initial public offering in 2003.

The Company has operated the Ogden facility since its initial public offering in 2003. In that time, the Company has invested funds and acquired necessary permits to increase the efficiency and expand the capacity of the Ogden facility through upgrades to the Ogden plant and solar evaporation ponds. The Company believes that the Ogden facility and its operating equipment are maintained in good working condition. The net book value of property, plant and equipment associated with the Ogden facility as of September 30, ~~2024~~2025 was $220,700,000, exclusive of mineral rights and the value of assets leased under operating leases.

The Ogden facility has procured and is operating in compliance with all required operating licenses, including permits pertaining to mineral extraction, effluent discharge and air permitting. The Ogden facility operates under a Title V air permit (# 5700001003), which is administered by the Utah Department of Environmental Quality. The permit covers emissions from the pond and plant operations and expires in December 2026. Surface water discharges from the Ogden facility are regulated under Utah Pollutant Discharge Elimination System permit UT0000647. The permit requires discharge monitoring for effluent flows from the nine outfalls that discharge into the saline waters of the Great Salt Lake and regulates inputs in pond and plant processes that may be discharged in project effluent.

~~Summaries~~43 of2025 ~~the~~FORM Ogden facility’s potassium and SOP mineral resources and mineral reserves as of September 30, 2024 and 2023 are shown in Tables 3 and 4, respectively. Summaries of the Ogden facility’s magnesium and magnesium chloride mineral resources and mineral reserves as of September 30, 2024 and 2023 are shown in Tables 5 and 6, respectively. Summaries of the Ogden facility’s sodium and sodium chloride mineral resources and mineral reserves as of September 30, 2024 and 2023 are shown in Tables 7 and 8, respectively. Joseph Havasi, who is employed full10-time as the Vice President, Natural Resources, of the Company, served as the QP and prepared the estimates of potassium and SOP, magnesium and magnesium chloride, and sodium and sodium chloride mineral resources and mineral reserves at the Ogden facility. The material assumptions and information pertaining to the Company’s disclosure of mineral resources and mineral reserves at the Ogden facility are based on the Technical Report Summary with respect to Potassium and SOP, Magnesium and Magnesium Chloride and Salt for the Ogden facility, dated November 29, 2021, as amended on December 14, 2022, with an effective date of September 30, 2021 K

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(5700001003), which is administered by the ~~“Ogden~~Utah ~~Potassium/Magnesium/Sodium~~Department ~~TRS”)~~of Environmental Quality. ~~This~~The ~~Form~~permit ~~10-K~~covers ~~also~~emissions ~~reflects~~from ~~more~~the ~~recent~~pond ~~information~~and ~~obtained~~plant operations and expires in December 2026. Surface water discharges from the QPOgden asfacility are regulated under Utah Pollutant Discharge Elimination System permit UT0000647. The permit requires discharge monitoring for effluent flows from the nine outfalls that discharge into the saline waters of ~~September~~the ~~30,~~Great ~~2024,~~Salt ~~which~~Lake ~~supplements~~and regulates inputs in pond and ~~updates~~plant ~~information~~processes ~~from~~that ~~such~~may ~~TRS~~be discharged in project effluent.

~~Table~~Summaries of the Ogden facility’s potassium and SOP mineral resources and mineral reserves as of September 30, 2025 and 2024 are shown in Tables 3 and 4, respectively. Summaries of the Ogden ~~Facility~~facility’s –magnesium ~~Summary~~and magnesium chloride mineral resources and mineral reserves as of ~~Potassium~~September 30, 2025 and ~~SOP~~2024 ~~Mineral~~are shown in Tables 5 and 6, respectively. Summaries of the Ogden facility’s sodium and sodium chloride mineral resources and mineral reserves as of September 30, 2025 and 2024 are shown in Tables 7 and 8, respectively. The Company’s Vice President, Natural Resources served as the Qualified Person and prepared the estimates of potassium and SOP, magnesium and magnesium chloride, and sodium and sodium chloride mineral resources and mineral reserves at the Ogden facility. The material assumptions and information pertaining to the Company’s disclosure of mineral resources and mineral reserves at the Ogden facility are based on the Technical Report Summary with respect to Potassium and SOP, Magnesium and Magnesium Chloride and Salt for the Ogden facility, dated November 29, 2021, as amended on December 14, 2022, with an effective date of September 30, ~~2024~~2021 (the “Ogden Potassium/Magnesium/Sodium TRS”). This Form 10-K also reflects more recent information obtained from the QP as of September 30, 2025, which supplements and ~~2023~~updates information from such TRS.

	September 30, 2024				September 30, 2023
Resource Area	Average Potassium Grade (mg/L)(7)	Potassium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Resources (tons)(1)(2)(3)(4)(5)	Average Potassium Grade (mg/L)(7)	Potassium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Resources (tons)(1)(2)(3)(4)(5)
Measured Resources
Total Measured Resources	—	—	—	—	—	—	—	—
Indicated Resources
Great Salt Lake North Arm	7,320	14,135,094	4,000	31,461,892	7,320	14,245,372	4,000	31,707,350
Great Salt Lake South Arm	3,060	26,057,971	1,660	58,000,000	3,060	26,057,971	1,660	58,000,000
Total Indicated Resources		40,193,065		89,461,892		40,303,343		89,707,350
Measured + Indicated Resources
Great Salt Lake North Arm	7,320	14,135,094	4,000	31,461,892	7,320	14,245,372	4,000	31,707,350
Great Salt Lake South Arm	3,060	26,057,971	1,660	58,000,000	3,060	26,057,971	1,660	58,000,000
Total Measured + Indicated Resources		40,193,065		89,461,892		40,303,343		89,707,350
Inferred Resources
Total Inferred Resources	—	—	—	—	—	—	—	—

Table 3. Ogden Facility – Summary of Potassium and SOP Mineral Resources at September 30, 2025 and 2024


	September 30, 2025				September 30, 2024
Resource Area	Average Potassium Grade (mg/L)(7)	Potassium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Resources (tons)(1)(2)(3)(4)(5)	Average Potassium Grade (mg/L)(7)	Potassium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Resources (tons)(1)(2)(3)(4)(5)
Measured Resources
Total Measured Resources	—	—	—	—	—	—	—	—
Indicated Resources
Great Salt Lake North Arm	7,320	14,009,771	4,000	31,182,949	7,320	14,135,094	4,000	31,461,892
Great Salt Lake South Arm	3,060	26,057,971	1,660	58,000,000	3,060	26,057,971	1,660	58,000,000
Total Indicated Resources		40,067,742		89,182,949		40,193,065		89,461,892
Measured + Indicated Resources
Great Salt Lake North Arm	7,320	14,009,771	4,000	31,182,949	7,320	14,135,094	4,000	31,461,892
Great Salt Lake South Arm	3,060	26,057,971	1,660	58,000,000	3,060	26,057,971	1,660	58,000,000
Total Measured + Indicated Resources		40,067,742		89,182,949		40,193,065		89,461,892
Inferred Resources
Total Inferred Resources	—	—	—	—	—	—	—	—

(1)Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that all or any part of the mineral resources will be converted into mineral reserves upon application of modifying factors.

(2)Mineral resources are reported in situ for the both the north arm and the south arm of the Great Salt Lake.

(3)Conversion of potassium to SOP uses a factor of 2.2258 tons of SOP per ton of potassium.


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(4)Included process recovery is approximately 7.8% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(5)Based on pricing data described in Section 18.1 of the Ogden Potassium/Magnesium/Sodium TRS. The pricing data is based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for SOP of $~~659~~672.9627 per ton. Sales prices are projected to increase to approximately $8,529 per ton for SOP through year 2161 (the current expected end of mine life).

(6)Estimated cut-off grade of approximately 4,000 milligrams of potassium per liter of brine extracted from the north arm of the Great Salt Lake, and a cut-off grade of 1,660 milligrams of potassium per liter of brine in the south arm of the Great Salt Lake, which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of potassium and SOP.

(7)Reported potassium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

42Table ~~2024~~4. ~~FORM~~Ogden ~~10-K~~Facility – Summary of Potassium and SOP Mineral Reserves at September 30, 2025 and 2024

Table of Contents COMPASS MINERALS INTERNATIONAL, INC.


	September 30, 2025				September 30, 2024
Reserve Area	Average Potassium Grade (mg/L)(7)	Potassium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Reserves (tons)(1)(2)(3)(4)(5)	Average Potassium Grade (mg/L)(7)	Potassium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Reserves (tons)(1)(2)(3)(4)(5)
Proven Reserves
Total Proven Reserves	—	—	—	—	—	—	—	—
Probable Reserves
Great Salt Lake North Arm	7,320	20,128,068	4,000	44,801,054	7,320	20,243,615	4,000	45,058,239
Great Salt Lake South Arm	—	—	—	—	—	—	—	—
Total Probable Reserves	7,320	20,128,068	4,000	44,801,054	7,320	20,243,615	4,000	45,058,239
Total Reserves
Great Salt Lake North Arm	7,320	20,128,068	4,000	44,801,054	7,320	20,243,615	4,000	45,058,239
Great Salt Lake South Arm	—	—	—	—	—	—	—	—
Total Reserves	7,320	20,128,068	4,000	44,801,054	7,320	20,243,615	4,000	45,058,239

Table 4. Ogden Facility – Summary of Potassium and SOP Mineral Reserves at September 30, 2024 and 2023

	September 30, 2024				September 30, 2023
Reserve Area	Average Potassium Grade (mg/L)(7)	Potassium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Reserves (tons)(1)(2)(3)(4)(5)	Average Potassium Grade (mg/L)(7)	Potassium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	SOP Reserves (tons)(1)(2)(3)(4)(5)
Proven Reserves
Total Proven Reserves	—	—	—	—	—	—	—	—
Probable Reserves
Great Salt Lake North Arm	7,320	20,243,615	4,000	45,058,239	7,320	20,345,292	4,000	45,284,552
Great Salt Lake South Arm	—	—	—	—	—	—	—	—
Total Probable Reserves	7,320	20,243,615	4,000	45,058,239	7,320	20,345,292	4,000	45,284,552
Total Reserves
Great Salt Lake North Arm	7,320	20,243,615	4,000	45,058,239	7,320	20,345,292	4,000	45,284,552
Great Salt Lake South Arm	—	—	—	—	—	—	—	—
Total Reserves	7,320	20,243,615	4,000	45,058,239	7,320	20,345,292	4,000	45,284,552

(1)Mineral reserves are as recovered, saleable product.

(2)Annual production rates for SOP are assumed to be 320,000 tons per year, relating to a depletion of 145,833 tons of potassium per year. Based on the QP’s reserve model, the life of mine is estimated to be 138 years.

(3)Conversion of potassium to SOP uses a factor of 2.2258 tons of SOP per ton of potassium.

(4)Included process recovery is approximately 7.8% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(6)Estimated cut-off grade of approximately 4,000 milligrams of potassium per liter of brine extracted from the north arm of Great Salt Lake, and a cut-off grade of 1,660 milligrams of potassium per liter of brine in the south arm of the Great Salt Lake, which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of potassium and SOP.

(7)Reported potassium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

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Table 5. Ogden Facility – Summary of Magnesium and Magnesium Chloride Mineral Resources at September 30, ~~2024~~2025 and ~~2023~~2024

	September 30, 2024				September 30, 2023
	September 30, 2025				September 30, 2024
Resource Area	Average Magnesium Grade (mg/L)(7)	Magnesium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Magnesium Chloride Resources (tons)(1)(2)(3)(4)(5)	Average Magnesium Grade (mg/L)(7)	Magnesium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Magnesium Chloride Resources (tons)(1)(2)(3)(4)(5)
Measured Resources
Total Measured Resources	—	—	—	—	—	—	—	—
Indicated Resources
Great Salt Lake North Arm	11,120	51,~~528~~341,~~897~~371	8,638	~~201~~200,~~632~~898,~~573~~785	11,120	51,~~719~~528,~~568~~897	8,638	~~202~~201,~~378~~632,~~669~~573
Great Salt Lake South Arm	4,785	40,122,668	3,039	157,000,000	4,785	40,122,668	3,039	157,000,000
Total Indicated Resources		91,~~651~~464,~~565~~039		~~358~~357,~~632~~898,~~573~~785		91,~~842~~651,~~236~~565		~~359~~358,~~378~~632,~~669~~573
Measured + Indicated Resources
Great Salt Lake North Arm	11,120	51,~~528~~341,~~897~~371	8,638	~~201~~200,~~632~~898,~~573~~785	11,120	51,~~719~~528,~~568~~897	8,638	~~202~~201,~~378~~632,~~669~~573
Great Salt Lake South Arm	4,785	40,122,668	3,039	157,000,000	4,785	40,122,668	3,039	157,000,000
Total Measured + Indicated Resources		91,~~651~~464,~~565~~039		~~358~~357,~~632~~898,~~573~~785		91,~~842~~651,~~236~~565		~~359~~358,~~378~~632,~~669~~573
Inferred Resources
Total Inferred Resources	—	—	—	—	—	—	—	—

(1) Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that all or any part of the mineral resource will be converted into mineral reserve upon application of modifying factors.

(2) Mineral resources are reported in situ for the both the north arm and the south arm of the Great Salt Lake.

(3) Conversion of magnesium to magnesium chloride uses a factor of 3.913 tons of magnesium chloride per ton of magnesium.

(4) Included process recovery is approximately 10.0% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(5) The pricing data is based on a five-year average of historical gross sales data for MgCl of $7485.4649 per ton. Gross sales prices are projected to increase to approximately and $1,~~100~~238.3959 per ton for MgCl through year 2161 (the current expected end of mine life).

(6) Estimated cut-off grade of approximately 8,638 milligrams of magnesium per liter of brine extracted from the north arm of the Great Salt Lake, and a cut-off grade of 3,039 milligrams of magnesium per liter of brine in the south arm of the Great Salt Lake which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of magnesium and magnesium chloride.

(7) Reported magnesium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

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Table 6. Ogden Facility – Summary of Magnesium and Magnesium Chloride Mineral Reserves at September 30, ~~2024~~2025 and ~~2023~~2024

	September 30, 2024				September 30, 2023
	September 30, 2025				September 30, 2024
Reserve Area	Average Magnesium Grade (mg/L)(7)	Magnesium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Magnesium Chloride Reserves (tons)(1)(2)(3)(4)(5)	Average Magnesium Grade (mg/L)(7)	Magnesium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Magnesium Chloride Reserves (tons)(1)(2)(3)(4)(5)
Proven Reserves
Total Proven Reserves	—	—	—	—	—	—	—	—
Probable Reserves
Great Salt Lake North Arm	11,120	23,~~856~~687,~~201~~428	8,638	9392,~~349~~688,~~316~~906	11,120	2423,~~027~~856,~~805~~201	8,638	9493,~~020~~349,~~802~~316
Great Salt Lake South Arm	4,785	—	3,039	—	4,785	—	3,039	—
Total Probable Reserves		23,~~856~~687,~~201~~428		9392,~~349~~688,~~316~~906		2423,~~027~~856,~~805~~201		9493,~~020~~349,~~802~~316
Total Reserves
Great Salt Lake North Arm	11,120	23,~~856~~687,~~201~~428	8,638	9392,~~349~~688,~~316~~906	11,120	2423,~~027~~856,~~805~~201	8,638	9493,~~020~~349,~~802~~316
Great Salt Lake South Arm	4,785	—	3,039	—	4,785	—	3,039	—
Total Reserves	—	23,~~856~~687,~~201~~428	—	9392,~~349~~688,~~316~~906	—	2423,~~027~~856,~~805~~201	—	9493,~~020~~349,~~802~~316

(1) Mineral reserves are as recovered, saleable product.

(2) Production rates for magnesium chloride are 620,000 tons per year. This relates to a depletion of 158,271 tons of magnesium per year. Based on the QP’s reserve model, the life of mine is estimated to be 139 years, based on potash operational longevity.

(3) Conversion of magnesium to magnesium chloride uses a factor of 3.913 tons of magnesium chloride per ton of magnesium.

(4) Included process recovery is approximately 10.0% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(5) The pricing data is based on a five-year average of historical gross sales data for MgCl of $7485.4649 per ton. Gross sales prices are projected to increase to approximately ~~and~~ $1,~~100~~238.3959 per ton for MgCl through year 2161 (the current expected end of mine life).

(6) Estimated cut-off grade of approximately 8,638 milligrams of magnesium per liter of brine extracted from the north arm of Great Salt Lake, and a cut-off grade of 3,039 milligrams of magnesium per liter of brine in the south arm of the Great Salt Lake which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of magnesium and magnesium chloride.

(7) Reported magnesium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

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Table 7. Ogden Facility – Summary of Sodium and Sodium Chloride Mineral Resources at September 30, ~~2024~~2025 and ~~2023~~2024

	September 30, 2024				September 30, 2023
	September 30, 2025				September 30, 2024
Resource Area	Average Sodium Grade (mg/L)(7)	Sodium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Sodium Chloride Resources (tons)(1)(2)(3)(4)(5)	Average Sodium Grade (mg/L)(7)	Sodium Resources (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Sodium Chloride Resources (tons)(1)(2)(3)(4)(5)
Measured Resources
Total Measured Resources	—	—	—	—	—	—	—	—
Indicated Resources
Great Salt Lake North Arm	97,530	435,~~568~~154,~~689~~357	75,757	1,~~107~~106,~~215~~162,~~607~~375	97,530	435,~~962~~568,~~634~~689	75,757	1,~~108~~107,~~217~~215,~~016~~607
Great Salt Lake South Arm	46,298	405,979,544	40,365	1,032,000,000	46,298	405,979,544	40,365	1,032,000,000
Total Indicated Resources		841,~~548~~133,~~233~~901		2,~~139~~138,~~215~~162,~~607~~375		841,~~942~~548,~~178~~233		2,~~140~~139,~~217~~215,~~016~~607
Measured + Indicated Resources
Great Salt Lake North Arm	97,530	435,~~568~~154,~~689~~357	75,757	1,~~107~~106,~~215~~162,~~607~~375	97,530	435,~~962~~568,~~634~~689	75,757	1,~~108~~107,~~217~~215,~~016~~607
Great Salt Lake South Arm	46,298	405,979,544	40,365	1,032,000,000	46,298	405,979,544	40,365	1,032,000,000
Total Measured + Indicated Resources		841,~~548~~133,~~233~~901		2,~~139~~138,~~215~~162,~~607~~375		841,~~942~~548,~~178~~233		2,~~140~~139,~~217~~215,~~016~~607
Inferred Resources
Total Inferred Resources	—	—	—	—	—	—	—	—

(1) Mineral resources are not mineral reserves and do not have demonstrated economic viability. There is no certainty that all or any part of the mineral resource will be converted to a mineral reserve upon application of modifying factors.

(2) Mineral resources are reported in-situ for both the north arm and south arm of the Great Salt Lake.

(3) Conversion of sodium to sodium chloride uses a factor of 2.542 tons of sodium chloride per ton of sodium.

(4) Included process recovery is approximately 10.0% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(5) The pricing data is based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical gross sales data for sodium chloride of $94107.9828 per ton. Gross sales prices are projected to increase to approximately $1,204.66 per ton for sodium chloride through year 2161 (the current expected end of mine life).

(6) Estimated cut-off grade of approximately 75,757 milligrams of sodium per liter of brine extracted from the north arm of Great Salt Lake, and a cut-off grade of 40,365 milligrams of sodium per liter of brine in the south arm of the Great Salt Lake which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of sodium and sodium chloride.

(7) Reported sodium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

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Table 8. Ogden Facility – Summary of Sodium and Sodium Chloride Mineral Reserves at September 30, ~~2024~~2025 and ~~2023~~2024

	September 30, 2024				September 30, 2023
	September 30, 2025				September 30, 2024
Reserve Area	Average Sodium Grade (mg/L)(7)	Sodium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Sodium Chloride Reserves (tons)(1)(2)(3)(4)(5)	Average Sodium Grade (mg/L)(7)	Sodium Reserves (tons)(1)(2)(4)(5)	Cut-Off Grade (mg/L)(6)	Sodium Chloride Reserves (tons)(1)(2)(3)(4)(5)
Proven Reserves
Total Proven Reserves	—	—	—	—	—	—	—	—
Probable Reserves
Great Salt Lake North Arm	97,530	61,~~968~~595,~~547~~648	75,757	~~157~~156,~~524~~576,~~046~~137	97,530	6261,~~323~~968,~~098~~547	75,757	~~158~~157,~~425~~524,~~314~~046
Great Salt Lake South Arm	46,298	—	40,365	—	46,298	—	40,365	—
Total Probable Reserves		61,~~968~~595,~~547~~648		~~157~~156,~~524~~576,~~046~~137		6261,~~323~~968,~~098~~547		~~158~~157,~~425~~524,~~314~~046
Total Reserves
Great Salt Lake North Arm	97,530	61,~~968~~595,~~547~~648	75,757	~~157~~156,~~524~~576,~~046~~137	97,530	6261,~~323~~968,~~098~~547	75,757	~~158~~157,~~425~~524,~~314~~046
Great Salt Lake South Arm	46,298	—	40,365	—	46,298	—	40,365	—
Total Reserves	—	61,~~968~~595,~~547~~648	—	~~157~~156,~~524~~576,~~046~~137	—	6261,~~323~~968,~~098~~547	—	~~158~~157,~~425~~524,~~314~~046

(1) Mineral reserves are as recovered, saleable product.

(2) Production rates for the sodium chloride are 1,045,000 tons per year. This relates to a depletion of 411,074 tons of sodium per year. Based on the QP’s reserve model, the life of mine is estimated to be 139 years, based on potash operational longevity.

(3) Conversion of sodium to sodium chloride uses a factor of 2.542 tons of NaCl per ton of sodium.

(4) Included process recovery is approximately 10.0% based on historical production results. Mining or metallurgical recovery is not applicable for this operation.

(6) Based on the economic analysis described in Section 19 of the Ogden Potassium/Magnesium/Sodium TRS, the QP estimated a cut-off grade of approximately 75,757 milligrams of sodium per liter of brine extracted from the north arm of Great Salt Lake, and a cut-off grade of 40,365 milligrams of sodium per liter of brine in the south arm of the Great Salt Lake which ultimately flows into the north arm of the Great Salt Lake. The QP assumes that when the north arm of the Great Salt Lake (where the Ogden facility sources its brine) reaches this concentration level, the Ogden facility will halt production of sodium and sodium chloride.

(7) Reported sodium concentration for the Great Salt Lake assumes an indicative lake level of 4,194.4 feet in the south arm and 4,193.5 feet in the north arm.

From September 30, ~~2023~~2024 to September 30, ~~2024~~2025, for both potassium and SOP, combined measured and indicated resources decreased by approximately 0.2731% and total reserves decreased by approximately 0.5057%. The decreases in the combined measured and indicated resources were attributable to depletion of potassium from the Great Salt Lake in connection with extraction operations of the Company and another salt producer, while the decrease in reserves was attributable to the Company’s production of SOP during that period.

COTE BLANCHE MINE

The Cote Blanche mine is a production stage, underground mine that produces rock salt primarily for highway deicing customers through a series of depots located along the Mississippi and Ohio rivers (and their major tributaries) and chemical and agricultural customers in the Southern and Midwestern United States. The Cote Blanche mine is located in south-central Louisiana in the Parish of St. Mary (T15S, R7E), at the northern edge of Cote Blanche Hummoch, commonly called “Cote Blanche Island.” Maps of the Cote Blanche mine property are shown in Figures 3 and 4.

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Figure 3. Cote Blanche Mine Property Location Map

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Figure 4. Aerial View of Cote Blanche Island

Cote Blanche Island is situated between the Intra-Coastal Waterway and Cote Blanche Bay in the Gulf of Mexico. The Cote Blanche mine is approximately 124 miles west of New Orleans, Louisiana, and approximately 26 miles southeast of New Iberia, Louisiana, on the Gulf Coast. The approximate coordinates of the site facilities are 29˚45’4” North and 91˚43’24” West. The site is accessed by surface roads to the Cote Blanche Landing, and then by ferry boat from the Cote Blanche Landing to Cote Blanche Island. The Company accesses Cote Blanche Island via two rights-of-way with a separate private landowner group: one for the landing for the ferry boat that the Company operates and maintains; and the other for the barge canal, which is utilized for barge access to the mine. The barges are managed by contract tug boat services.

The Cote Blanche mine has a barge loading dock, administrative offices and other services-related structures. Power is supplied to the site by CLECO Power from nearby power lines that are fed directly from the main power grid and there are telephone and cellular connections. Water is provided to the Cote Blanche mine by privately owned and operated wells that are on the mine site. The Cote Blanche mine is well established and has been in the community for over 50 years. The communities of New Iberia, Broussard and Lafayette, Louisiana, have the required infrastructure (shopping, emergency services, schools, etc.) to support the workforce. New Iberia is served by a small regional airport and a transcontinental railroad.

The Company leases the entirety of Cote Blanche Island from a private ownership group, except for 115 acres of the southeastern sector of the island (the “115 Acre Tract”), for a total mineral lease of 1,520 acres. The lease grants salt rights to the Company for all salt from the ground surface downward 3,000 feet, except for salt located within the 115 Acre Tract. The lease also grants surface rights in the western and southwestern sectors of Cote Blanche Island, with access rights to the mine road that extends north-south from the surface lease area to the Cote Blanche Crossing.

The lease has an effective end date of June 30, 2060, unless earlier terminated. In the event that no actual mining is being completed during any five consecutive years, the lessor has the option to cancel the lease. As lessee, the Company may exercise two options to extend the term of the lease, each for a 25-year period upon the same terms and conditions contained in the lease. The Company has a minimum royalty based on 1,500,000 tons of salt hoisted annually. Under the terms of the lease, the royalty for each calendar year is equal to the Net F.O.B. Mine Sales Revenue Per Ton (as defined below), multiplied by the Applicable Royalty Rate (as defined below), multiplied by the number of tons of salt hoisted from the Cote Blanche mine in that calendar year. The “Net F.O.B. Mine Sales Revenue Per Ton” for each calendar year is the quotient of the total bulk sales revenue (excluding any taxes) of the Company and its affiliates for salt sold from the Cote Blanche mine in bulk (in units of 1 short ton or more) (“Total Bulk Sales Revenue”) reduced for all freight in, freight out, fuel surcharge, additives, depot/warehouse storage, handling and operating costs, promotions/discounts and other costs as are properly deducted under generally accepted accounting principles in that calendar year, divided by the total number of tons sold. The number of tons of salt sold is the same number of tons used to generate the Total Bulk Sales Revenue. The “Applicable Royalty Rate” is 5.5%.

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accounting principles in that calendar year, divided by the total number of tons sold. The number of tons of salt sold is the same number of tons used to generate the Total Bulk Sales Revenue. The “Applicable Royalty Rate” is 5.5%.

The lease further provides that if, on or before January 1 of 2034, 2059 or 2084 (each, a “Review Year”), the lessor or the Company determines that, in operation, the royalty provisions of the lease result in the lessor receiving more or less than 5.5% of the fair value of salt at the minehead free of all costs at that point (the “Royalty Standard”), such party shall deliver to the other party on or before January 1 of the Review Year a written statement of its reasons why the Royalty Standard is not being met, a computation of the amount that will satisfy the Royalty Standard and a proposed revision to the royalty provisions of the lease that will cause the royalty provisions to comply with the Royalty Standard. On or before January 30 of the Review Year, the other party is required to deliver to the first party a written statement of its opinion as to whether the royalty provisions as proposed comply with the Royalty Standard and a response to the first party’s statement delivered under the preceding sentence. If the parties are not in agreement, the parties are required to commence arbitration.

The lease provides that the lessor has full right to grant future oil, gas and other mineral leases, except salt, provided that each such future oil, gas and mineral lease shall expressly obligate the lessee to cooperate with the Company in the conduct of its operations in order that the purposes of both leases may be best effectuated. The lease obligates the Company to cooperate with the oil, gas and mineral lessee so as to permit drilling of oil and/or gas wells.

The Cote Blanche mine operates with a production schedule targeting approximately 2.2 million tons of salt per year. That target can vary significantly depending on the severity of winter weather conditions and the resulting market demand for road salt.

Domtar Industries, Inc. constructed the Cote Blanche mine over four years beginning in 1961 with 8-foot and 14-foot shafts and the barge loadout facility. Salt production commenced in 1966. The DG Harris Company purchased the Cote Blanche mine in 1990, which operated as Carey Salt Co. thereafter. The salt assets of The DG Harris Company were sold to IMC in 1997. IMC sold a majority of its salt operations, including the Cote Blanche mine, to Apollo Management V, L.P. through an entity called Compass Minerals Group in 2001. Following a leveraged recapitalization, the company now known as Compass Minerals International, Inc. completed an initial public offering in 2003.

Mining at the Cote Blanche mine occurs in 75-foot mining horizons at specific depths below the surface. To date, the salt dome has been mined at three levels, including the 1,300-foot level, which was mined from 1965 to 1986; the 1,100-foot level, which was mined from 1986 to 2002; and the current 1,500-foot level, which began in 1998 to and is expected to remain in operation through 2026. The Company is in the process of developing a ramp to an extension of the 1,300-foot level, for which mining is projected to start in 2022. Active mining on both the 1,300-foot level and the 1,500-foot level is anticipated to take place from 2022 to 2026. The Company’s current mine plan focuses on completion of the 1,500-foot level with future expansion to the 1,700-foot level and finally advancing to the 1,900-foot level. At this time, mining is not anticipated below the 1900-foot level.

There has been extensive historical oil and gas exploration on and adjacent to Cote Blanche Island, but the Company only has access to mapping and reports that are publicly available from external subsurface exploration. While the historical data provide a strong depiction of the salt ore body, the Company has undertaken in-seam seismic and mud-rotary drilling to verify and validate salt diapir position, morphology and margin at the Cote Blanche mine. The nature of salt diapirs lends itself to a strong understanding of the homogeneity of the morphology and mineralogy of the ore body. Thus, the primary concerns within the salt diapir are understanding the margin of the diapir to support the mine plan by ensuring geotechnical stability, and mapping the localized presence of sandstone partings and seams that are encountered from time to time as well as sheer planes along margins of salt stock formations. The combination of historic data collected through externally funded and directed seismic and drilling programs for oil and gas exploration in strata surrounding the diapir, combined with Compass Minerals’ salt diapir morphology validation drilling has created a reasonably strong characterization of the definition of the salt diapir.

As the mining continues and progresses to the next deeper mining level at 1,700 feet and eventually to the 1,900-foot level, definition of the upper surface of the salt diapir is no longer necessary as mining will be below the current mining level. Therefore, mud-rotary drilling to validate the salt dome surface will no longer be necessary and instead the mining operation will continue its in-seam seismic data collection to assess the potential for anomalies as mining progresses to the outer margins of the mine plan, and verify that the lateral margins of the diapir are not within the Company’s self-determined, 400-foot setback of mineral extraction.

The Cote Blanche mine utilizes the room and pillar method of extraction. In this method, excavations (rooms) are recovered by mining and are alternated with areas of undisturbed salt (pillars) that form the necessary support for maintaining stability of the mine roof. The layout of the rooms and pillars and their respective sizes are optimized to maximize the ratio of salt extracted, relative to in situ salt, while still meeting safety and surface subsidence requirements. All levels in the current mine plan, 1,300-foot through the 1,900-foot levels, are currently mining or are planned to be operated in the same manner, with the same mining parameters and with the same set of unit operations, altered only by the footprint of the mining of the room and pillar method as modified to reflect the constraints of the planned level and the lateral constraints of the salt dome contours of each level.

~~The~~52 ~~current~~2025 ~~room~~FORM and pillar layout has an extraction ratio of approximately 56% within the mined room area, but the overall extraction ratio of the property, taking into account barrier pillars and unmined zones and interruptions from oil wells among other anomalies is about 51%. Rooms are mined in a progression of two phases creating a total room height of 75 feet when completed. The rooms have a nominal width of 50 feet and are bounded by 10010-~~foot square pillars. Variations in room and~~ K

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~~pillar~~relative ~~dimensions~~to ~~are~~in ~~observed~~situ ~~due~~salt, towhile ~~production~~still ~~blasting~~meeting safety and ~~scaling,~~surface sosubsidence ~~values~~requirements. ~~are~~All ~~approximate.~~levels Toin ~~achieve~~the 75current ~~feet~~mine ofplan, ~~height~~1,300-foot ~~rooms~~through the 1,900-foot levels, are ~~initially~~currently ~~developed~~mining ~~using~~or aare 30planned ~~foot~~to ~~top-cut~~be ~~(horizontal~~operated ~~drill~~in ~~and~~the ~~blast)~~same manner, ~~which~~with isthe ~~then~~same ~~vertically~~mining ~~drilled~~parameters and ~~blasted~~with ~~(benched)~~the ansame ~~additional~~set 45of ~~feet~~unit operations, ~~with~~altered 5only ~~feet~~by ofthe ~~sub-drilling.~~footprint ~~Loading~~of ~~and~~the ~~hauling~~mining isof ~~completed~~the ~~with~~room ~~diesel~~and ~~powered~~pillar ~~loading~~method ~~equipment~~as ~~and~~modified ~~haul~~to ~~trucks.~~reflect ~~Development~~the ~~mining~~constraints ~~typically~~of ~~leads~~the ~~ahead~~planned oflevel ~~benching~~and orthe ~~room~~lateral ~~advance~~constraints byof ~~approximately~~the ~~one~~salt ~~and~~dome acontours ~~half~~of ~~years~~each level.

The current room and pillar layout has an extraction ratio of approximately 56% within the mined room area, but the overall extraction ratio of the property, taking into account barrier pillars and unmined zones and interruptions from oil wells among other anomalies is about 51%. Rooms are mined in a progression of two phases creating a total room height of 75 feet when completed. The rooms have a nominal width of 50 feet and are bounded by 100-foot square pillars. Variations in room and pillar dimensions are observed due to production blasting and scaling, so values are approximate. To achieve 75 feet of height, rooms are initially developed using a 30 foot top-cut (horizontal drill and blast), which is then vertically drilled and blasted (benched) an additional 45 feet, with 5 feet of sub-drilling. Loading and hauling is completed with diesel powered loading equipment and haul trucks. Development mining typically leads ahead of benching or room advance by approximately one and a half years.

The process for salt production at the Cote Blanche mine focuses on particle size reduction of the salt product. Rock salt is processed and sized by underground crushers and the mill before it is hoisted to the surface. The mill has two distinct halves: the mine run circuit and the whole mill. Only chemical quality and non-chemical quality salt can be processed through the whole mill. Ice control quality salt is processed through the mine run circuit. Once the salt has been sized accordingly, it is either stockpiled or placed directly onto a barge for transport to market. The main stockpile area allows separate piles for chemical, non-chemical, and ice control grade salt.

The Cote Blanche mine is operated with modern mining equipment and utilizes subsurface improvements, such as vertical shaft lift systems, milling and crushing facilities, maintenance and repair shops and extensive raw materials handling systems. The milling and crushing facilities were constructed when the Cote Blanche mine developed the 1,500 foot level in 2001. As of September 30, ~~2024~~2025, the net book value for the plant, property and equipment at the Cote Blanche mine is $83,200,000, exclusive of mineral rights and the value of assets leased under operating leases.

The Cote Blanche mine has procured and is operating in compliance with required operating licenses, including permits pertaining to mineral extraction, effluent discharge and air permitting. The Company will be required to renew the current air permit at the Cote Blanche mine, which is administered by the Louisiana Department of Environmental Quality, when it expires in December 2026. Surface water discharges from the site are regulated under Louisiana Pollutant Discharge Elimination System (LPDES) permit LA0103233. The permit requires discharge monitoring for effluent flows from the three outfalls that discharge into the saline waters of the Intracoastal Waterway and Cote Blanche Bay. The State of Louisiana does not require an operating permit for the Cote Blanche mine. Air and NPDES permits are maintained by the site. The site is located in a Coastal Protection Zone and therefore any new site disturbance requires permitting by the U.S. Army Corps of Engineers and the Louisiana Office of Coastal Management. Initial operations at the site predate the Coastal Resources rules so no formal reporting is required under this process.

There are no mine closure plans for the Cote Blanche mine. Once the lease agreement terminates, the Company has six months to vacate the mine of any personal property it wishes to recover before the landownership group assumes control of the mine and either continues mining or initiates other commercial or industrial uses of the surface mine site and underground void space.

Summaries of the Cote Blanche mine’s salt mineral resources and mineral reserves as of September 30, ~~2024~~2025 and ~~2023~~2024 are shown in Tables 10 and 11, respectively. ~~Joseph~~The ~~Havasi,~~Company’s ~~who is employed full-time as the~~ Vice President, Natural Resources, ~~of the Company,~~ served as the QPQualified Person and prepared the estimates of salt mineral resources and mineral reserves at the Cote Blanche mine. The material assumptions and information pertaining to the Company’s disclosure of mineral resources and mineral reserves at the Cote Blanche mine are based on the Technical Report Summary dated November 16, 2021, as amended on December 14, 2022, with an effective date of September 30, 2021 (the “Cote Blanche TRS”). This Form 10-K also reflects more recent information obtained from the QP as of September 30, ~~2023~~2025, which supplements and updates information from such TRS. The Company periodically reviews its mining plans, including which levels of the mine to develop. Changes in the mining plan in the future may result in increases in expected capital costs or changes that may adversely impact our reported reserves. If mineral reserves were materially impacted, the QP would update the TRS accordingly.

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Table 10. Cote Blanche Mine – Summary of Salt Mineral Resources at September 30, ~~2024~~2025 and ~~2023~~2024

	Salt Resources (tons)(1)(2)(3)(4)(5)(6)(7)
Resource Area(2)(8)	September 30,~~2024~~2025	September 30,~~2023~~2024
Measured Resources
1,300-Foot Level	2423,~~388~~618,~~583~~722	2524,~~140~~388,~~266~~583
1,500-Foot Level	64,~~633~~243,~~758~~195	96,~~372~~633,~~555~~758
Total Measured Resources	3127,~~022~~861,~~341~~917	3431,~~512~~022,~~821~~341
Indicated Resources
1,300-Foot Level	12,373,509	12,373,509
1,500-Foot Level	9,028,840	9,028,840
1,700-Foot Level(9)	361,~~584~~357,~~762~~904	361,584,762
1,900-Foot Level(9)	246,045,618	246,045,618
Total Indicated Resources	~~629~~628,~~032~~805,~~729~~871	629,032,729
Measured + Indicated Resources
1,300-Foot Level	3635,~~762~~992,~~092~~231	3736,~~513~~762,~~775~~092
1,500-Foot Level	1513,~~662~~272,~~598~~035	1815,~~401~~662,~~395~~598
1,700-Foot Level(9)	361,~~584~~357,~~762~~904	361,584,762
1,900-Foot Level(9)	246,045,618	246,045,618
Total Measured + Indicated Resources	~~660~~656,~~055~~667,~~070~~788	~~663~~660,~~545~~055,~~550~~070
Inferred Resources
1,700-Foot Level(9)	32,915,833	32,915,833
1,900-Foot Level(9)	130,851,531	130,851,531
Total Inferred Resources	163,767,364	163,767,364

(1)Mineral resources are reported in situ. Mineral resources are not mineral reserves and do not have demonstrated economic viability.

(2)Underground mineral resources are reported based on assumed 75-foot mining horizons, discounted for areas not accessible due to proximity to oil wells.

(3)Tonnage was calculated based on a tonnage factor of 0.0675 tons per cubic foot.

(4)Included process recovery is 94% based on production experience. Included mining recovery is approximately 56% based on the room and pillar layout.

(5)Although the actual sodium chloride grade is less than 100%, it is not considered in the resource, as the final saleable product is the in situ product, as-present after processing (i.e., the saleable product includes any impurities present in the in situ rock).

(6)A cut-off grade was not utilized for the calculation as the in situ product quality is relatively constant and saleable after processing.

(7)There are multiple saleable products based on salt quality from the operation (rock salt for road deicing and chemical grade salt). For simplicity, all sales are assumed at the lower value (and higher tonnage) product, rock salt, and are based on pricing data described in Section 16 of the Cote Blanche TRS. The pricing data is based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for rock salt for road deicing of $7175.5974 per ton. Sales prices are projected to increase to approximately $763.94 per ton for rock salt for road deicing through year 2138 (the current expected end of mine life).

(8)Based on approximate areas of: 5,399,000 square feet (“ft2”) for the 1,300-foot level; 2,991,000 ft2 for the 1,500-foot level; 45,721,000 ft2 for the 1,700-foot level; 50,293,000 ft2 for the 1,900-foot level; and 104,404,000 ft2 in the aggregate.

(9)The 1,700-foot and 1,900-foot levels have been approximated using the 1,300-foot and 1,500-foot level contours, respectively, in alignment to the 400-foot contact distance restriction and site and safety constraints.

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Table 11. Cote Blanche Mine – Summary of Salt Mineral Reserves at September 30, ~~2024~~2025 and ~~2023~~2024

	Salt Reserves (tons)(1)(3)(4)(5)(6)(7)
Reserve Area(2)(8)	September 30,~~2024~~2025	September 30,~~2023~~2024
Proven Reserves
1,300-Foot Level	12,~~735~~330,~~563~~308	1312,~~131~~735,~~249~~563
1,500-Foot Level	21,~~969~~711,~~828~~436	42,~~411~~969,~~531~~828
Total Proven Reserves	1514,~~705~~041,~~391~~744	1715,~~542~~705,~~780~~391
Probable Reserves
1,700-Foot Level(9)	113,~~853~~734,~~955~~537	113,853,955
1,900-Foot Level(9)	122,693,422	122,693,422
Total Probable Reserves	236,~~547~~427,~~377~~959	236,547,377
Total Reserves
1,300-Foot Level	12,~~735~~330,~~563~~308	1312,~~131~~735,~~249~~563
1,500-Foot Level	21,~~969~~711,~~828~~436	42,~~411~~969,~~531~~828
1,700-Foot Level(9)	113,~~853~~734,~~955~~537	113,853,955
1,900-Foot Level(9)	122,693,422	122,693,422
Total Reserves	~~252~~250,~~252~~469,~~768~~703	~~254~~252,~~090~~252,~~157~~768

(1)Ore reserves are as recovered, saleable product.

(2)Underground mineral reserves are reported based on assumed 75-foot mining horizons, discounted for areas not accessible due to proximity to oil wells.

(3)Tonnage was calculated based on a tonnage factor of 0.0675 tons per cubic foot.

(4)Included process recovery is 94% based on production experience. Included mining recovery is approximately 56% based on the room and pillar layout.

(5)Although the actual sodium chloride grade is less than 100%, it is not considered in the reserve, as the final saleable product is the in situ product, as-present (i.e., the saleable product includes any impurities present in the in situ rock).

(6)A cut-off grade was not utilized for the calculation as the in situ product quality is relatively constant and saleable after processing.

(8)Based on approximate areas of: 5,399,000 ft2 for the 1,300-foot level; 2,991,000 ft2 for the 1,500-foot level; 45,721,000 ft2 for the 1,700-foot level; 50,293,000 ft2 for the 1,900-foot level; and 104,404,000 ft2 in the aggregate.

From September 30, ~~2023~~2024 to September 30, ~~2024~~2025, combined measured and indicated resources at the Cote Blanche mine decreased by approximately 0.5351% and total reserves decreased by approximately 0.7271%. The decreases in salt resources and reserves were attributable to depletion of salt in connection with extraction operations of the Company.

GODERICH MINE

The Goderich mine is a production stage, underground mine that produces rock salt primarily for highway use and as feed product for other uses. The Goderich mine is located in southwestern Ontario, Canada, on the eastern shore of Lake Huron. The Goderich mine is located west of the town of Goderich, Ontario, on an isthmus in the mouth of the Maitland River, as it enters Lake Huron. Maps of the Goderich mine property are shown in Figures 5 and 6.

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Figure 5. Goderich Mine Property Location Map

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Figure 6. Lease and Mine Map: Goderich Mine

The Goderich mine is approximately 60 miles northwest of London, Ontario, and 120 miles west of Toronto, Ontario. Its approximate coordinates are 43˚ 44’ 50” North and 81˚ 43’ 30” West. Access to the Goderich mine is considered excellent. The town of Goderich has established infrastructure for both mining and exporting salt and can be accessed via regional highways from Toronto from the east (2.5 hours). The triangular-shaped mine site is surrounded by the lake on three sides and the Maitland River on the north side. Goderich Harbor and the Goderich mine site are accessed via North Harbor Road, a municipally owned and maintained road that connects the harbor area to Highway 21. The Goderich mine is connected to local power, water, natural gas and sewage infrastructure. Primary logistics for transporting mined product include the rail siding at the mine site and direct loading into ships or barges in Goderich Harbor. The town of Goderich provides all necessary resources for the Goderich mine, with a ready labor supply, housing, hotels, food and all other typical facilities. The close proximity to rail, port and roads provides easy access for all logistical needs. Commercial air travel is available from London, Ontario, Toronto, Ontario, and Detroit, Michigan, all of which are in relative proximity to the site.

The Goderich mine site is located on 16.3 acres of Company-owned land (PIN 41369-0004) on a man-made peninsula consisting of several large buildings and silos associated with mining and material handling, a ship loading facility and three shafts. The Company actively mines salt west of its owned land under Salt Mining Lease No. 110134, dated February 5, 2024, with the Ontario Ministry of Energy, Northern Development and Mines (“MNDM”), comprising approximately 13,195 acres. The lease has a 21-year term that expires on May 31, 2043. The current royalty rate paid is $0.729 per tonne.

The Goderich mine is the largest underground rock salt mine in the world. Based on the proposed mine layout and using a 6.5 million tons per annum average production run rate assumption, the Goderich mine has a current mine life of approximately 69 years, assuming the Company is able to successfully renew the lease following the expiration of the 21-year renewal term in 2043, which the Company currently expects.

~~Salt~~57 ~~production~~2025 ~~began~~FORM in Goderich, Ontario, in 1867 by Sifto Canada (“Sifto”) after an unsuccessful search for oil uncovered a vast bed of rock salt. Sifto used basic solution mining and evaporation, now known as mechanical evaporation, to begin the nearby Goderich plant. 10-K

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~~1957.~~Salt ~~The Goderich mine started~~ production ~~upon~~began ~~the completion of the first shaft~~ in ~~1959. Additional increases in production were enabled after a second mine shaft and a third mine shaft were completed in 1962 and 1982~~Goderich, ~~respectively. In 1990~~Ontario, ~~Domtar~~in ~~Chemicals~~1867 ~~Limited~~by ~~(previously~~Sifto ~~known~~Canada ~~as Dominion Tar and Chemical Company Ltd.~~(“Sifto”) ~~sold~~after ~~Sifto~~an tounsuccessful ~~the~~search ~~North American Salt Company, a subsidiary of D.G. Harris & Associates. In 1993, D.G. Harris & Associates founded Harris Chemical Group as a holding company~~ for ~~salt~~oil ~~operations,~~uncovered ~~which was acquired by IMC in 1997. IMC sold~~ a ~~majority~~vast bed of ~~its~~rock salt ~~operations, including the Goderich mine, to Apollo Management V, L~~.P. ~~through~~Sifto anused ~~entity~~basic ~~called~~solution ~~Compass~~mining ~~Minerals~~and ~~Group in 2001. Following a leveraged recapitalization~~evaporation, ~~the company~~ now known as ~~Compass~~mechanical ~~Minerals International~~evaporation, ~~Inc.~~to ~~completed~~begin anthe ~~initial~~nearby ~~public~~Goderich ~~offering in 2003~~plant.

In 1956, Sifto received approval to operate an underground salt mine while under the ownership of Dominion Tar and Chemical Company Ltd. Initial drilling at the Goderich mine started in 1955 with the sinking of the first shaft beginning in 1957. The Goderich mine started production upon the completion of the first shaft in 1959. Additional increases in production were enabled after a second mine shaft and a third mine shaft were completed in 1962 and 1982, respectively. In 1990, Domtar Chemicals Limited (previously known as Dominion Tar and Chemical Company Ltd.) sold Sifto to the North American Salt Company, a subsidiary of D.G. Harris & Associates. In 1993, D.G. Harris & Associates founded Harris Chemical Group as a holding company for salt operations, which was acquired by IMC in 1997. IMC sold a majority of its salt operations, including the Goderich mine, to Apollo Management V, L.P. through an entity called Compass Minerals Group in 2001. Following a leveraged recapitalization, the company now known as Compass Minerals International, Inc. completed an initial public offering in 2003.

The Goderich mine’s underground infrastructure is situated in the A-2 salt bed approximately 1,750 feet to 1,760 feet below the surface at the mine shafts’ location. The A-2 salt bed in the shaft area is approximately 79 feet thick. The regional stratigraphic sequence is well understood from many wells drilled across the basin and locally in the Goderich, Ontario, area. The salt strata are highly continuous over the basin, and most of the major salt units can be traced for hundreds of miles. On a local scale, the continuity of the salt beds can be impacted by the presence of pinnacle reefs, displacement by faults, or the local leaching of salt. The Company can use various tools to characterize geological conditions in nearby areas to assess the possibility of encountering these local ground conditions at the mine. Accordingly, the Company has engaged third parties to conduct in-seam seismic surveys and, more recently, has begun use of ground penetrating radar to identify disturbances in salt continuity and the thickness of the A-2 salt bed in development.

The Goderich mine progresses development of main entries in advance of bench mining. The subsequent benches achieve the remainder of the 60-foot room height for room production. Development and bench mining progress at an approximate 40:60 ratio in terms of area of advance in the mine plan and are part of the production process. As needed, underground rooms for facility support functions have been and will be developed in excavated areas of the mine. This includes development of shaft areas on each level for hoist equipment, design, planning and development of ramp structures from one level to the subsequent, lower level as required, installation of underground work facilities such as maintenance shops and storage rooms. As mining progresses, development also encompasses the design, placement, repair and maintenance of support infrastructure such as crushers, screens and other plant in support of mining. All portions of mine development within the A-2 salt are planned to be operated in the same manner and mining method, with the same mining parameters with the same set of unit operations.

The general method of mining employed at the Goderich mine is known as room and pillar mining. Beginning in 2012 and 2013, the Company advanced the Goderich mine to mechanized room and pillar mining as continuous mining machines (each a “CMM”) replaced the previous under-cutter/over-cutter equipment and drilling and blasting sequence in the development areas of the mine. By 2017, the Company was engaged in continuous mining of the entire 60-foot face of the mined rooms in multiple lifts with a goal of improving efficiency and safety, reducing costs and reducing the amount of diesel equipment utilized underground, thus largely eliminating the use of drilling and blasting at the Goderich mine. The Company continues to upgrade its CMM fleet at the Goderich mine.

Certain mining units at the Goderich mine are equipped with both a CMM and a flexible conveyor train (“FCT”), a dynamic move-up unit and a belt storage unit. On these mining units, the CMM cuts the salt directly from the face and discharges it into a hopper on the end of the FCT. From the FCT, the rock salt is offloaded to the main underground belt conveyance system where it is then transported to the underground crushers and the mill. Other mining units are also equipped with a CMM, but are supported with rubber-tired haulage equipment to transfer salt. Salt mined from these CMMs is transferred from the face by rubber-tired haulage to a centralized dump point with a crusher and then follows the same process as the other units once the salt is put onto the underground conveyance system. Rock salt is processed and sized at the underground crushers and the mill before being hoisted to the surface. Salt is stockpiled at the surface in domes. The salt is then distributed to depots, packaging facilities and customers via ship (approximately 80%), and rail car and truck (approximately 20%). The net book value for the plant, property and equipment at the Goderich mine is $206,300,000 as of September 30, ~~2024~~2025, exclusive of mineral rights and the value of assets leased under operating leases.

The Goderich mine has procured and is operating in compliance with all required operating licenses, including permits pertaining to mineral extraction, effluent discharge and air permitting. The Ontario Ministry of Energy, Northern Development and Mines regulates closure for the Goderich mine. The most recent closure plan was approved by the ministry in 2021. Long-term cleanup of the site will essentially include demolishing surface facilities, removal of surface infrastructure and restoring a natural alvar ecological community on the surface, flooding of the workings, and decommissioning (plugging). The Goderich mine operates under two air permits issued by the Ontario Ministry of Environment, Conservation and Parks, one for the lab (8-1131-96-007), and the other for the garage for welding exhaust (5522-78NUN2). Site drainage into Snug Harbour and the Maitland River is permitted pursuant to Certificate of Approval 2342-7ULQEU and Environmental Compliance Approval 1236-8YGK8A, respectively, issued by the Ontario Ministry of Environment, Conservation and Parks.

~~Summaries~~58 of2025 ~~the~~FORM ~~Goderich mine’s salt mineral resources and mineral reserves as of September 30, 2024 and 2023 are shown in Tables 12 and 13, respectively. Joseph Havasi, who is employed full~~10-time as the Vice President, Natural Resources, of the Company, served as the QP and prepared the estimates of salt mineral resources and mineral reserves at the Goderich mine. The material assumptions and information pertaining to the Company’s disclosure of mineral resources and mineral reserves at the Goderich mine are based on the Technical Report Summary dated November 16, 2021, as amended on December 14, 2022, K

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~~with~~term ancleanup ~~effective~~of ~~date~~the site will essentially include demolishing surface facilities, removal of ~~September~~surface 30infrastructure and restoring a natural alvar ecological community on the surface, ~~2021~~flooding (of the ~~“Goderich~~workings, ~~TRS”~~and decommissioning (plugging). ~~This~~The ~~Form~~Goderich ~~10-K~~mine ~~also~~operates ~~reflects~~under ~~more~~two ~~recent~~air ~~information,~~permits ~~including~~issued ~~revised~~by ~~capital~~the ~~expenditure~~Ontario ~~forecasts~~Ministry of Environment, ~~obtained~~Conservation ~~from~~and ~~the~~Parks, QPone asfor ofthe ~~September~~lab 30(8-1131-96-007), ~~2024,~~and ~~which~~the ~~supplements~~other ~~and~~for ~~updates~~the ~~information~~garage ~~from~~for ~~such~~welding ~~TRS~~exhaust (5522-78NUN2). ~~These~~Site ~~changes~~drainage tointo ~~the~~Snug ~~capital~~Harbour ~~expenditures~~and ~~forecasts~~the ~~would~~Maitland ~~affect~~River ~~the~~is ~~NPV~~permitted ~~and~~pursuant ~~IRR~~to ~~figures~~Certificate ~~stated~~of inApproval ~~Section~~2342-7ULQEU 19and ofEnvironmental ~~the~~Compliance ~~Goderich~~Approval ~~TRS~~1236-8YGK8A, ~~but~~respectively, ~~salt~~issued ~~resources~~by orthe ~~reserves~~Ontario ~~would~~Ministry ~~not~~of beEnvironment, ~~affected~~Conservation and Parks.

Summaries ~~Table~~of the Goderich mine’s salt mineral resources and mineral reserves as of September 30, 2025 and 2024 are shown in Tables 12 and 13, respectively. The Company’s Vice President, Natural Resources served as the Qualified Person and prepared the estimates of salt mineral resources and mineral reserves at the Goderich ~~Mine~~mine. –The ~~Summary~~material assumptions and information pertaining to the Company’s disclosure of ~~Salt~~mineral ~~Mineral~~resources ~~Resources~~and mineral reserves at the Goderich mine are based on the Technical Report Summary dated November 16, 2021, as amended on December 14, 2022, with an effective date of September 30, ~~2024~~2021 (the “Goderich TRS”). This Form 10-K also reflects more recent information, including revised capital expenditure forecasts, obtained from the QP as of September 30, 2025, which supplements and ~~2023~~updates information from such TRS. These changes to the capital expenditures forecasts would affect the NPV and IRR figures stated in Section 19 of the Goderich TRS, but salt resources or reserves would not be affected.

	Salt Resources (tons)(1)(2)(4)(5)(6)(7)(8)
Resource Area(3)(9)	September 30,2024	September 30,2023
Measured Resources	—	—
Indicated Resources	1,441,611,742	1,453,008,026
Measured + Indicated Resources	1,441,611,742	1,453,008,026
Inferred Resources	148,200,000	148,200,000

Table 12. Goderich Mine – Summary of Salt Mineral Resources at September 30, 2025 and 2024


	Salt Resources (tons)(1)(2)(4)(5)(6)(7)(8)
Resource Area(3)(9)	September 30, 2025	September 30, 2024
Measured Resources	—	—
Indicated Resources	1,430,188,004	1,441,611,742
Measured + Indicated Resources	1,430,188,004	1,441,611,742
Inferred Resources	148,200,000	148,200,000

(2)All figures have been rounded to reflect the relative accuracy of the estimates.

(3)Underground mineral resources are reported based on an expected representative A-2 salt bed thickness of 82 feet.

(4)Tonnage was calculated based on a tonnage factor of 0.0675 tons per cubic foot.

(5)Included process recovery is 97.5% based on production experience. Included mining recovery is approximately 38.7% based on the room and pillar mine plan.

(6)Although the actual sodium chloride grade is less than 100%, it is not considered in the resource, as the final saleable product is the in situ product, as-present after processing (i.e., the saleable product includes any impurities present in the in situ rock).

(7)A cut-off grade was not utilized for the calculation as the in situ product quality is relatively constant and saleable after processing.

(8)There are multiple saleable products based on salt quality from the operation (rock salt for road deicing and chemical grade salt). For simplicity, all sales are assumed at the lower value (and higher tonnage) product, rock salt and are based on pricing data described in Section 16 of the Goderich TRS. The pricing data is based on a five-year average (~~2020~~2021 through ~~2024~~2025) of historical sales data for rock salt for road deicing of $6463.3865 per ton. Sales prices are projected to increase to approximately $319.63 per ton for rock salt for road deicing through year 2094 (the current expected end of mine life).

(9)Based on an area of approximately 575,257,000 square feet for the A-2 salt bed within the lease area.

Table 13. Goderich Mine – Summary of Salt Mineral Reserves at September 30, ~~2024~~2025 and ~~2023~~2024

	Salt Reserves (tons)(1)(2)(3)(4)(5)(6)(7)(8)
Reserve Area(3)(9)	September 30,~~2024~~2025	September 30,~~2023~~2024
Proven Reserves	—	—
Probable Reserves	~~453~~449,~~390~~080,~~625~~163	~~457~~453,~~690~~390,~~728~~625
Total Reserves	~~453~~449,~~390~~080,~~625~~163	~~457~~453,~~690~~390,~~728~~625

(1)Ore reserves are as recovered, saleable product.

(2)All figures have been rounded to reflect the relative accuracy of the estimates.

(3)Reserve volume assumes a mining thickness of 18 meters (approximately 60 feet) production, 8.5 meters (approximately 28 feet) mains.

(4)Tonnage was calculated based on a tonnage factor of 0.0675 tons per cubic foot.

(5)Included process recovery is 97.5% based on production experience. Included mining recovery is approximately 38.7% based on the room and pillar mine plan.


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(6)Although the actual sodium chloride grade is less than 100%, it is not considered in the reserve, as the final saleable product is the in situ product, as-present after processing (i.e., the saleable product includes any impurities present in the in situ rock).

(7)A cut-off grade was not utilized for the calculation as the in situ product quality is relatively constant and saleable after processing.

(9)Based on an area of approximately 575,257,000 square feet for the A-2 salt bed within the lease area.

From September 30, ~~2023~~2024 to September 30, ~~2024~~2025, combined measured and indicated resources at the Goderich mine decreased by approximately 0.8% and total reserves decreased by approximately 1.0%. The decreases in salt resources and reserves were attributable to depletion of salt in connection with extraction operations of the Company.

INTERNAL CONTROLS DISCLOSURE

The modeling and analysis of the Company’s resources and reserves has been developed by Company mine personnel and reviewed by several levels of internal management, including the QP. The development of such resources and reserves estimates, including related assumptions, was a collaborative effort between the QP and Company staff. This section summarizes the internal control considerations for the Company’s development of estimations, including assumptions, used in resource and reserve analysis and modeling.

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estimates, including related assumptions, was a collaborative effort between the QP and Company staff. This section summarizes the internal control considerations for the Company’s development of estimations, including assumptions, used in resource and reserve analysis and modeling.

When determining resources and reserves, as well as the differences between resources and reserves, management developed specific criteria, each of which must be met to qualify as a resource or reserve, respectively. These criteria, such as demonstration of economic viability, points of reference and grade, are specific and attainable. The QP and Company management agree on the reasonableness of the criteria for the purposes of estimating resources and reserves. Calculations using these criteria are reviewed and validated by the QP.

Estimations and assumptions were developed independently for each significant mineral location. All estimates require a combination of historical data and key assumptions and parameters. When possible, resources and data from generally accepted industry sources, such as governmental resource agencies, were used to develop these estimations.

The Company’s salt-producing locations do not utilize exploration in the development of their assumptions around mineral resources or reserves. The mineral deposits are restricted in access by bodies of water, and industry techniques used for geological exploration for other types of mineral deposits, specifically drilling, are degradational to the salt ore being assessed. Given the nature of the salt mineral, this limitation impedes the validation of mineral resources and reserves using drilling. Accordingly, geophysical techniques are utilized at both Goderich and Cote Blanche to assist in mine planning, and to verify that there are no obstructions ahead of advancement of the mine in the form of geological anomalies or structural features, such as faults that could affect future mining. In conducting these geophysical campaigns, including in-seam seismic and ground penetrating radar technologies, the Company is able to identify the continuity of ore-body ahead of mining.

Geographical modeling and mine planning efforts serve as a base assumption for resource estimates at each significant salt-producing location. These outputs have been prepared by both Company personnel and third-party consultants, and the methodology is compared to industry best practices. Mine planning decisions, such as mining height, execution of mining and ground control, are determined and agreed upon by Company management. Management adjusts forward-looking models by reference to historic mining results, including by reviewing performance versus predicted levels of production from the mineral deposit, and if necessary, re-evaluating mining methodologies if production outcomes were not realized as predicted. Ongoing mining and interrogation of the mineral deposit, coupled with product quality validation pursuant to industry best practices and customer expectations, provides further empirical evidence as to the homogeneity, continuity and characteristics of the mineral resource. Ongoing quality validation of production also provides a means to monitor for any potential changes in ore-body quality. Also, ongoing monitoring of ground conditions within the mine, surveying for evidence of subsidence and other visible signs of deterioration that may signal the need to re-evaluate rock mechanics and structure of the mine ultimately inform extraction ratios and mine design, which underpin mineral reserve estimates.

For the mass load estimations in the Great Salt Lake brine, the Utah Geological Survey (“UGS”) as of September 2020 (water samples across five locations) and United States Geological Survey bathymetry data from 2000 (sonar sampling) were used as the basis for the modeling of sodium, magnesium, and potassium mass loads, the critical ions of interest. Key data from the common sampling points were compared to confirm data correlated. Because these reports are independently produced, undergo inter-agency review, and their key data points correlate, no further evaluation of sampling methods or quality control were reviewed by Company management or the QP. The Company also collected potassium and other ion data during this campaign in order to relate ion relationships and ratios in its modelling as well. These data were derived from samples collected by the QP in hermetically sealed samples containers, sent to an external laboratory under chain of custody, analyzed by an accredited laboratory for metals analysis, and the data were reviewed and validated by SRK Consulting. Review of the data derived from the Company’s sampling campaign revealed that the data were of sufficient quality to integrate in to the historic UGS data set for further mass load modelling.


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were reviewed by Company management or the QP. The Company also collected potassium and other ion data during this campaign in order to relate ion relationships and ratios in its modelling as well. These data were derived from samples collected by the QP in hermetically sealed samples containers, sent to an external laboratory under chain of custody, analyzed by an accredited laboratory for metals analysis, and the data were reviewed and validated by SRK Consulting. Review of the data derived from the Company’s sampling campaign revealed that the data were of sufficient quality to integrate in to the historic UGS data set for further mass load modelling.

The QP is satisfied that the hydrological/chemical model for the Great Salt Lake reflects the current hydrological and chemical information and knowledge. The mineral resource model is informed by brine sampling data spanning approximately 55 years and recent bathymetry data. Continuity of the resource is not a concern, as the lake is a visible, continuous body. The Company’s experience in extracting potassium and other salts from the Great Salt Lake for over 50 years under dynamic conditions, such as changing lake elevations and ion concentrations, lends confidence regarding the ability to operate under varying conditions, utilizing ion concentrations as a tool to monitor reserve estimates and make operational decisions.

Management also assesses risks inherent in mineral resource and reserve estimates, such as the accuracy of geophysical data that is used to support mine planning, identify hazards and inform operations of the presence of mineable deposits. Also, management is aware of risks associated with potential gaps in assessing the completeness of mineral extraction licenses, entitlements or rights, or changes in laws or regulations that could directly impact the ability to assess mineral resources and reserves or impact production levels. Risks inherent in overestimated reserves can impact financial performance when revealed, such as changes in amortizations that are based on life of mine estimates.

OTHER PROPERTIES

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The Company packages its Salt segment products at three additional Company-owned and operated facilities located in Illinois, Minnesota and New York. The Company estimates that its annual combined packaging capacity at these three facilities is 275,000 tons. This packaging capacity is based on the Company’s estimate of the tons that can be packaged at these facilities assuming a normal amount of scheduled down-time and operation of its facilities under normal working conditions, including staffing levels. The Company has the capability to significantly increase its annual packaging capacity by increasing its staffing levels in response to demand, which would require incremental labor and other costs.

ITEM 3. LEGAL PROCEEDINGS

We are involved in the legal proceedings described in Part II, Item 8, Note 108. Income Taxes and Part II, Item 8, Note 1311. toCommitments and Contingencies of our Consolidated Financial Statements and, from time to time, various routine legal proceedings and claims arising from the ordinary course of our business. These primarily involve tax assessments, disputes with former employees and contract labor, commercial claims, product liability claims, personal injury claims and workers’ compensation claims. Management cannot predict the outcome of legal proceedings and claims with certainty. Nevertheless, management believes that the outcome of legal proceedings and claims, which are pending or known to be threatened, even if determined adversely, will not, either individually or in the aggregate, have a material adverse effect on our results of operations, cash flows or financial condition, except as otherwise described in Part II, Item 8, Note 108. ~~and~~Income Taxes, Part II, Item 8, Note 1311. Commitments and Contingencies of our Consolidated Financial Statements, and Item 8, Note 18. Subsequent Event.


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ITEM 4. MINE SAFETY DISCLOSURES

Information concerning mine safety violations or other regulatory matters required by Section 1503(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act and Item 104 of Regulation S-K is incorporated by reference to Exhibit 95 to this Form 10-K report.

Information about our Executive Officers

Below is information about each person who was or is an executive officer as of September 30, ~~2024~~2025, and as of the date of the filing of this ~~report~~Form 10-K. The table sets forth each person’s name, position and age as of the date of the filing of this ~~report~~Form 10-K.

Name

Age

Position

Edward C. Dowling Jr.

6970

President and Chief Executive Officer and Director

Jeffrey Cathey

Chief Financial Officer

Peter Fjellman

Chief Financial Officer

Mary L. Frontczak

Chief Legal and Administrative Officer and Corporate Secretary

Patrick Merrin

Chief Operations Officer

Jenny Hood

Chief Supply Chain Officer

Ben Nichols

Chief Commercial Officer

Ben Nichols

Chief Sales Officer

Amy Tills

Chief Human Resources Officer

Ashley Ward

Chief Accounting Officer

Edward C. Dowling Jr., President and Chief Executive Officer and Director, joined Compass Minerals as president and chief executive officer (CEO) in January 2024. He continues to serve on the company’s board of directors, as he has since March 2022. Mr. Dowling has more than 3035 years of leadership experience and international mining expertise. Prior to joining Compass Minerals, Mr. Dowling served as the president, CEO and member of the board of directors of SSR Mining Inc. (f/k/a Alacer Gold Corp.), a publicly traded hard rock mining company (2008-2012), and was chair of the board (2013-2020). Previously, he was president and CEO of Meridian Gold Inc. (2006-2007), executive director for mining and exploration at De Beers S.A. (2004-2006) and executive vice president for operations at Cleveland-Cliffs Inc. (1998-2004). Additionally, he formerly served as chair of the board of PJSC Polyus and of Copper Mountain Mining Corporation. Mr. Dowling currently serves on the board of directors of Wesdome Gold Mines as of May 2025 and has served on the board of directors of Teck Resources Ltd. from 2012 to 2025.

~~Jeffrey~~Peter ~~Cathey~~Fjellman, Chief Financial Officer, joined Compass Minerals in ~~December~~January ~~2023~~2025 as chief ~~accounting~~financial officer. InMr. ~~June~~Fjellman ~~2024,~~brings heover ~~was~~30 ~~named~~years ~~chief~~of ~~financial~~experience ~~officer~~leading ~~and~~finance isteams ~~responsible~~across ~~for~~diverse ~~all~~industrial, ~~aspects~~manufacturing ofand ~~financial~~logistics ~~management~~sectors, ~~including~~most ~~accounting,~~recently ~~reporting,~~serving ~~tax,~~as ~~internal~~senior ~~audit,~~vice ~~treasury,~~president ~~financial~~of ~~planning~~finance, Americas and ~~analysis~~Asia Pacific for GXO Logistics, ~~and~~a ~~investor~~spinoff ~~relations.~~of MrXPO Logistics. ~~Cathey~~Prior ~~brings~~to ~~over~~GXO 15Logistics, ~~years~~his ofroles ~~financial~~included ~~leadership~~CFO, ~~experience~~Americas infor ~~public~~ABB, a global power and ~~private~~automation ~~companies~~products tomanufacturer; ~~his~~vice ~~new~~president ~~role.~~of ~~Before~~finance, ~~joining~~North ~~Compass~~America, ~~Minerals~~at Danaher Corporation, hea ~~spent~~global 10life ~~years~~sciences inand diagnostics company; and positions of ~~growing~~increasing responsibility at ~~Crestwood~~Newell ~~Equity~~Rubbermaid ~~Partners~~Corporation, ~~LP.~~a ~~Previously,~~global heconsumer ~~held~~goods ~~roles~~manufacturer. atMr. ~~Shamrock~~Fjellman ~~Trading~~began ~~Corporation~~his ~~and~~career ~~Ernst~~on &the ~~Young~~audit ~~LLP~~team at KPMG.

~~Mary~~Patrick ~~L. Frontczak~~Merrin, Chief ~~Legal~~Operations ~~and Administrative~~ Officer ~~and Corporate Secretary~~, joined Compass Minerals in ~~November~~March ~~2019~~2025 ~~and~~as ~~assumed~~chief ~~her~~operations ~~current~~officer ~~position in February 2020~~(“COO”). Prior to ~~her~~joining ~~current~~the ~~role~~company, ~~she~~Mr. Merrin served as ~~the~~executive ~~Company’s~~vice ~~chief~~president ~~legal~~of ~~officer~~technical ~~and~~services ~~corporate~~at ~~secretary~~Lundin Mining Corporation, a diversified Canadian base metals miner. Before ~~joining~~Lundin, ~~Compass~~he ~~Minerals~~was appointed chief executive officer at Copper Mountain Mining Corporation, Msa copper mining company. ~~Frontczak~~Previous ~~had~~roles ~~served~~include asCOO of mining at Washington Companies, a diversified holding company in the transportation, mining, construction and shipbuilding industries; and senior vice president of Canadian operations at Newcrest Mining and Goldcorp, both gold mining companies acquired by Newmont Corporation.

59Ben Nichols, Chief Commercial Officer, joined Compass Minerals in November 2004 as sales and marketing analyst and held positions of increasing responsibility until his promotion in March 2018, to vice president, salt, consumer and industrial. In January 2020, he was named vice president, plant nutrition. Mr. Nichols was appointed chief sales officer in January 2024 ~~FORM~~to ~~10-K~~oversee the sales, product management and marketing functions for the Salt and Plant Nutrition businesses. In March 2025, he was named chief commercial officer.


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~~and~~Amy ~~general~~Tills, ~~counsel~~Chief ofHuman ~~POET~~Resources ~~LLC~~Officer, anjoined ~~ethanol~~Compass ~~and~~Minerals ~~other~~as ~~biorefined~~chief ~~products~~human ~~producer,~~resources ~~since~~officer ~~2017~~in September 2025. ~~Prior~~Before tojoining ~~POET~~Compass Minerals, Ms. Tills developed a background in transforming organization cultures and she ~~headed~~brings ~~the~~more ~~legal~~than ~~department~~20 atyears ~~Bunge~~of ~~North~~experience ~~America,~~in anhuman ~~agribusiness~~resources leadership and ~~food~~labor ~~ingredient~~relations ~~company,~~ from ~~2015~~various toindustries ~~2017~~ and ~~held~~global ~~roles~~operations. Most recently, she served as global vice president of ~~increasing~~human ~~responsibility~~resources at ~~Peabody~~Fluke ~~Energy~~ Corporation. Previously, ~~the~~she ~~world’s~~was ~~largest~~vice ~~private~~president ~~sector~~of ~~coal~~human ~~company~~resources, ~~from~~global ~~2005~~cooling, toat ~~2015~~SPX ~~and~~Corporation. ~~The~~Additionally, ~~May~~she ~~Department~~gained ~~Store~~experience ~~Company~~at ~~from~~manufacturing ~~1996~~companies, toincluding ~~2005.~~Honeywell, ~~Her~~Amcor ~~experience~~Ltd., ~~also~~and ~~includes~~Goodyear ~~five~~Tire ~~years~~and inRubber ~~private practice~~Company.

~~Jenny~~Ashley ~~Hood~~Ward, Chief ~~Supply~~Accounting ~~Chain~~ Officer, joined Compass Minerals in ~~September~~July ~~2019~~2024 as vice president, ~~supply~~corporate ~~chain.~~controller Inand ~~August 2023, she~~ was ~~named head of fire retardants. Ms. Hood was~~ appointed chief ~~supply~~accounting ~~chain~~ officer in ~~January~~June ~~2024~~2025. ~~and~~Prior isto ~~responsible~~joining ~~for~~the ~~leading~~company, ~~all~~Ms. ~~commercial~~Ward ~~and~~spent ~~innovation~~10 ~~activities~~years ~~for~~with ~~our~~Crestwood ~~long-term~~Equity ~~Fire~~partners ~~Retardant~~and ~~business.~~held ~~She~~positions ~~also provides oversight~~ of ~~our~~increasing ~~global supply chain function~~responsibility, including ~~the~~assistant ~~customer~~controller ~~experience,~~and ~~integrated business planning~~director, ~~logistics~~operational accounting and ~~procurement~~fixed ~~teams~~assets. ~~Prior~~After toreceiving ~~joining~~a ~~Compass~~Bachelor ~~Minerals, Ms. Hood was vice president~~ of ~~transportation~~Business atAdministration ~~Contura~~in ~~Energy~~accounting ~~(2018-2019)~~from ~~and~~Wichita ~~vice~~State ~~president~~University, ofshe ~~marketing~~began ~~and logistics at Bowie Resource Partners (2014-2018). Early in~~ her career, ~~she worked~~ in ~~positions~~accounting ~~of increasing responsibility within supply chain and logistics~~ at ~~Alpha~~Flint ~~Natural~~Hills Resources, ~~(2011-2014)~~a ~~and~~wholly ~~Massey~~owned ~~Energy~~subsidiary ~~Company~~of ~~(2005-2011)~~Koch Industries.

~~Ben~~63 ~~Nichols,~~2025 ~~Chief~~FORM Sales Officer, joined Compass Minerals in November 2004 as sales and marketing analyst and held positions of increasing responsibility until his promotion in March 2018, to vice president, salt, consumer and industrial. In January 2020, he was named vice president, plant nutrition. He has been serving as vice president, commercial, since May 2021. Mr. Nichols was appointed chief sales officer in January 2024 to oversee the sales, product management and marketing functions for the Salt and Plant Nutrition businesses.10-K

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PART II

ITEM 5. MARKET FOR THE REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

CUMULATIVE TOTAL STOCK RETURN

The following Stockholder Performance Graph compares the cumulative total return on the Company’s common stock with the Russell 2000 Index and a peer group index with companies with market capitalization from $1 billion to $3 billion. The performance graph below uses a market capitalization index because the Company does not believe it has a reasonable line-of-business peer group. The graph assumes that the value of the investment in common stock and each index was $100 on December 31, ~~2019~~2020 and that all dividends were reinvested. Peer group indices use beginning of period market capitalization weighting.

The share price performance shown on the graph is not necessarily indicative of future price performance. Information used in the graph was prepared by Zacks Investment Research, Inc. Used with permission. All rights reserved. Copyright 1980–2024. Index Data: Copyright Russell Investments. Used with permission. All rights reserved. The performance graph above is furnished and not filed for purposes of the Securities Act and the Exchange Act. The performance graph is not soliciting material subject to Regulation 14A.

COMMON STOCK DATA

Our common stock, $0.01 par value, trades on the New York Stock Exchange under the symbol CMP.

HOLDERS

On December 118, ~~2024~~2025, the number of holders of record of our common stock was ~~251~~228.

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DIVIDEND POLICY

We paid dividends for the first and second quarters of fiscal 2024. On April 22, 2024, the Board of Directors determined not to declare dividends for the foreseeable future in order to align our capital allocation priorities with our corporate focus on accelerating cash flow generation and debt reduction. The payment of any future dividends will be at the discretion of the Board of Directors and will depend on our financial condition, results of operations, capital requirements, and any other factors deemed relevant by the Board of Directors.

ITEM 6. RESERVED

Part II, Item 6 is no longer required as the SEC has adopted certain amendments to Regulation S-K that eliminate Item 301 of Regulation S-K.

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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The statements in this discussion regarding the industry outlook, our expectations for the future performance of our business, and the other non-historical statements in this discussion are forward-looking statements. These forward-looking statements are subject to numerous risks and uncertainties, including, but not limited to, the risks and uncertainties described in Item 1A, “Risk Factors.” You should read the following discussion together with Item 1A, “Risk Factors” and the Consolidated Financial Statements and Notes thereto included elsewhere in this ~~report~~Form 10-K.

COMPANY OVERVIEW

Compass Minerals is a leading global provider of essential minerals, ~~focused~~including onsalt, ~~safely~~consisting ~~delivering~~of ~~where~~sodium ~~and~~chloride ~~when it matters to help solve nature’s challenges for customers~~ and ~~communities.~~magnesium ~~Our~~chloride ~~Salt segment products help keep roadways safe during winter weather~~ and ~~are used in numerous other consumer, industrial, chemical and agricultural applications. Our Plant Nutrition segment is the leading North American producer of~~ sulfate of potash, ~~which~~(SOP”) ~~is used in the production of~~ specialty ~~fertilizers for high-value crops and turf and helps improve the quality and yield of crops, while supporting sustainable agriculture~~fertilizer. ~~We are working to develop long-term fire-retardant solutions to help combat wildfires.~~ As of September 30, ~~2024~~2025, we operate 12 production and packaging facilities with ~~nearly~~more than 1,~~900~~800 personnel throughout the U.S., Canada and the ~~U.K.~~UK, including:

•The largest rock salt mine in the world in Goderich, Ontario, Canada;

•The largest dedicated rock salt mine in the ~~U.K.~~UK in Winsford, Cheshire;

•A solar evaporation facility located near Ogden, Utah, which is both the largest sulfate of potash specialty fertilizer production site and the largest solar salt production site in the Western Hemisphere; and

•Several mechanical evaporation facilities producing consumer and industrial salt.

WeOur ~~concluded~~Salt ~~that~~segment ~~certain~~provides ofhighway ~~our~~deicing ~~assets~~salt ~~met~~to ~~the~~customers ~~criteria~~in ~~for~~North ~~classification~~America asand ~~discontinued operations in~~ the ~~first~~UK ~~quarter~~as ofwell ~~2021,~~ as ~~discussed~~consumer ~~further~~deicing inand ~~the~~water ~~“Discontinued~~conditioning ~~Operations” section below. As a result~~products, weingredients ~~are~~used ~~presenting two reportable segments, Salt and Plant Nutrition (which was previously known as the Plant Nutrition North America segment)~~ in ~~this~~consumer ~~“Management’s Discussion~~ and ~~Analysis~~commercial offood ~~Financial~~preparation, ~~Condition~~ and ~~Results~~other ofsalt-based ~~Operations.”~~products ~~See~~for ~~Item~~consumer, 8industrial, ~~Note~~chemical 14and toagricultural ~~our~~applications ~~Consolidated~~in ~~Financial~~North ~~Statements for more information~~America. ~~Unless~~In ~~otherwise~~the ~~indicated~~UK, ~~the~~we ~~information~~operate ~~and~~a ~~amounts~~records ~~provided~~management inbusiness ~~this~~utilizing ~~“Management’s~~excavated ~~Discussion~~areas ~~and Analysis~~ of ~~Financial~~our ~~Condition~~Winsford ~~and~~salt ~~Results~~mine ofwith ~~Operations”~~one ~~pertain~~other tolocation ~~continuing~~in ~~operations~~London, England.

Our Salt segment provides highway deicing salt to customers in North America and the U.K. as well as consumer deicing and water conditioning products, ingredients used in consumer and commercial food preparation, and other salt-based products for consumer, industrial, chemical and agricultural applications in North America. In the U.K., we operate a records management business utilizing excavated areas of our Winsford salt mine with one other location in London, England.

Our Plant Nutrition segment produces and markets SOP products in various grades worldwide to distributors and retailers of crop inputs, as well as growers and for industrial uses. We market our SOP under the trade name Protassium+.

Debt Refinancing. In ~~May~~June ~~2023~~2025, we ~~completed~~issued ~~the~~$650.0 ~~purchase~~million aggregate principal amount of ~~Fortress,~~our 8.00% Senior Notes due 2030 in a ~~fire~~private ~~retardant~~offering ~~company~~(the ~~working~~“2030 toNotes”). ~~develop~~We ~~long-term~~used ~~aerial~~the ~~and~~net ~~ground~~proceeds ~~fire~~from ~~retardant~~the ~~products~~2030 Notes to ~~help~~(i) ~~combat~~repay ~~wildfires~~all ~~(see~~outstanding ~~Part~~amounts ~~II,~~under ~~Item~~our 8senior secured credit facility, ~~Note~~including $43.5 million under the revolving credit facility and $191.3 ofmillion under our ~~Consolidated~~term ~~Financial~~loan, ~~Statements~~(ii) redeem approximately $350.0 ~~December~~million ~~31,~~of ~~2023~~our ~~marked~~outstanding ~~the~~6.75% ~~end~~Senior ofNotes ~~Fortress's~~due ~~first~~2027, ~~commercially~~(iii) ~~operating~~pay ~~fire~~transaction-related ~~season~~fees ~~with~~and ~~the~~expenses, ~~U.S.~~(iv) ~~Forest~~increase ~~Service~~cash on our balance sheet, and (~~“USFS”~~v) for general corporate purposes. AsThe ~~described~~redemption resulted in ~~Item~~a 8,loss ~~Note~~on 2debt extinguishment of ~~our~~$7.6 ~~Consolidated~~million, ~~Financial~~which ~~Statements,~~is ~~the~~included ~~USFS~~in ~~did~~Loss ~~not~~on ~~award~~extinguishment usof adebt ~~contract~~in the Consolidated Statements of Operations for the ~~calendar~~fiscal ~~2024~~year ~~fire~~ended ~~season~~September 30, 2025. WeSee ~~are~~the ~~evaluating~~Liquidity ~~various~~and ~~alternatives~~Capital ~~regarding~~Resources ~~the~~section ~~path~~below ~~forward~~and ~~for~~Item ~~the~~8, ~~Fortress~~Note ~~business~~10. ~~given~~Long ~~recent~~Term ~~developments.~~Debt and Finance Lease Liabilities of our Consolidated Financial Statements for additional information.

AsFortress ~~discussed~~Exit. inIn ~~Item~~May 82023, ~~Note~~we 2completed ofthe ~~our~~purchase ~~Consolidated~~of ~~Financial~~Fortress ~~Statements~~North America, weLLC ~~recognized~~(“Fortress), a fire retardant company working to develop long-~~lived~~term ~~asset~~aerial ~~impairment,~~and ~~net,~~ground offire ~~$15.6 million,~~retardant anproducts ~~inventory~~to ~~impairment~~help ofcombat $2wildfires.~~4 million~~ ~~and~~In ~~goodwill~~March ~~impairment~~2025, ofwe ~~$32.0 million~~took ~~related~~measures to ~~Fortress~~align ~~and~~our ~~goodwill~~cost ~~impairment~~structure to our current business needs as part of ~~$51.0 million~~a ~~related~~larger strategic refocus to improve the profitability of our core Salt and Plant Nutrition ~~during~~businesses, including the ~~second~~process ~~quarter~~ of ~~fiscal~~exiting ~~2024.~~the ~~Failure~~Fortress tobusiness ~~obtain~~and ~~full~~terminating ~~qualification~~the byemployment ~~the~~of ~~USFS~~all orFortress employees. As a ~~decision~~result byof ~~the~~impairment ~~USFS~~tests ~~not~~performed toduring ~~enter~~fiscal ~~into~~year ~~commercial~~ended ~~agreements~~September ~~with~~30, ~~respect~~2025, towe ~~Fortress’s~~recorded ~~non-magnesium~~a ~~chloride~~$53.0 million loss on impairment of long-~~based~~lived ~~fire~~assets ~~retardant~~related ~~products~~to ~~could~~customer ~~result~~relationships inand ~~additional~~trade ~~impairments~~name and a $0.7 million impairment related to the remaining Fortress ~~business~~property, plant and equipment. See Item 8, Note 2. Summary of Significant Accounting Policies of our Consolidated Financial Statements for additional information.

~~Additionally,~~We wecontinue ~~had~~to ~~been~~monitor ~~pursuing~~the ~~development~~effects of athe ~~sustainable~~tariffs ~~lithium~~imposed ~~salt~~by ~~resource~~the ~~near~~U.S. ~~Ogden,~~administration UTduring to2025, ~~support~~ the ~~North~~reciprocal ~~American~~tariffs ~~battery~~and ~~market.~~retaliatory ~~However,~~tariffs asimposed ~~described~~by inother ~~Part II~~countries, ~~Item~~and 8,the ~~Note~~impact 8on of our ~~Consolidated~~business. ~~Financial~~Our ~~Statements,~~salt weand ~~have~~fertilizer ~~terminated~~production ~~our~~in ~~pursuit~~Canada ofis ~~the~~qualified ~~lithium~~under ~~development. Consequently, we evaluated~~ the ~~capitalized~~United ~~assets,~~States-Mexico-Canada ~~including~~(“USMCA”) ~~site~~trade ~~preparation,~~agreement. ~~project engineering~~Accordingly, ~~equipment~~our ~~and~~exports ~~materials~~from ~~and~~Canada ~~capitalized~~into ~~labor~~the ~~and~~United ~~interest,~~States ~~and~~are ~~recorded~~exempt anfrom ~~impairment~~tariffs ~~charge~~at ofthis ~~$74~~time.~~8 million.~~

WeOn ~~focus~~July on4, ~~building~~2025, ~~intrinsic~~the ~~value~~U.S. byenacted ~~growing~~a ~~our~~budget ~~earnings~~reconciliation ~~before~~package ~~interest,~~known ~~taxes,~~as ~~depreciation~~the ~~and~~“One ~~amortization~~Big Beautiful Bill Act of 2025” (“~~EBITDA~~OBBBA”), which includes both tax and bynon-tax ~~improving~~provisions. ~~our~~We ~~asset~~are ~~quality~~evaluating inthe aeffects ~~way~~of ~~that~~these ~~optimizes~~changes ~~our~~and ~~cash~~other ~~flows.~~provisions Weof ~~can~~this ~~employ~~legislation on our ~~free~~consolidated ~~cash~~financial ~~flow~~statements; ~~and~~however, ~~other~~we ~~sources~~do ofnot ~~liquidity~~expect tothe ~~re-invest~~changes resulting from the tax provisions in ~~our~~OBBBA ~~business,~~will ~~pay~~have ~~down~~a ~~debt~~material ~~and~~impact ~~make~~on ~~acquisitions.~~the Company’s results of operations due to the timing of our fiscal year reporting.

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~~Discontinued~~RESULTS ~~Operations~~OF OPERATIONS—For the Fiscal Year September 30, 2025, Compared to the Fiscal Year September 30, 2024

OnCONSOLIDATED ~~March~~RESULTS ~~16,~~OF 2021, our Board of Directors approved a plan to sell our South America chemicals and specialty plant nutrition businesses, our investment in Fermavi and our North America micronutrient product business with the goal of reducing our leverage and enabling increased focus on optimizing our core businesses and as described further in Item 8, Note 1 and Note 4 to our Consolidated Financial Statements, we subsequently sold our South America specialty plant nutrition business, a component of our North America micronutrient business, our Fermavi investment and our South America chemicals business, respectively. We believe these dispositions were conducted through a single disposal plan representing a strategic shift that has had a material effect on our operations and financial results. Consequently, the Specialty Businesses qualify for presentation as discontinued operations in accordance with U.S. Generally Accepted Accounting Principles. The dispositions were completed during fiscal 2022; accordingly, the results of operations of the Specialty Businesses are presented as discontinued operations in the Consolidated Statements of Operations for the fiscal year ended September 30, 2022.OPERATIONS

~~Consolidated~~CONSOLIDATED ~~Results~~RESULTS ofCOMMENTARY: ~~Operations~~— For the Fiscal Year Ended September 30, 2025, Compared to the Fiscal Year Ended September 30, 2024

~~The~~•Total ~~following~~sales increased 11.3%, ~~discussion~~or ~~and~~$126.5 ~~analysis~~million, ~~are~~due ~~for~~to ~~the~~higher ~~fiscal~~Salt ~~year~~and ~~ended~~Plant ~~September~~Nutrition ~~30,~~segment ~~2024~~sales, ~~compared~~partially tooffset ~~the~~by ~~same~~lower ~~period~~Fortress infire ~~2023,~~retardant ~~unless otherwise stated~~sales. ~~For~~The aincrease ~~discussion~~in ~~and~~Salt ~~analysis~~sales ofwas ~~the~~primarily ~~fiscal~~driven ~~year~~by ~~ended~~higher ~~September~~sales 30volumes, ~~2023,~~partially ~~compared~~offset toby ~~the~~lower ~~same~~combined ~~period~~average sales prices. The increase in ~~2022~~Plant Nutrition sales, ~~please~~in ~~refer~~comparison to ~~Management’s~~the ~~Discussion~~prior ~~and~~fiscal ~~Analysis~~year, ofprimarily ~~Financial~~reflects ~~Condition~~higher ~~and~~sales ~~Results~~volumes, ofpartially ~~Operations~~offset ~~included~~by inlower ~~Part~~average ~~II,~~sales ~~Item~~price. 7The results of ~~our~~operations ~~Form~~of ~~10-K/A~~Fortress included sales of $14.7 million for the fiscal year ended September 30, ~~2023~~2024 and no sales in fiscal 2025. On May 30, ~~filed~~2025, ~~with~~we completed the ~~SEC~~sale onof ~~October~~the ~~29,~~Fortress ~~2024~~fire retardant assets.

*•Operating ~~Refer~~income was $25.3 million for the fiscal year ended September 30, 2025, compared to ~~“—Reconciliation~~an ofoperating ~~Net~~loss of $(~~Loss~~116.8) ~~Earnings~~million, ~~from~~for ~~Continuing~~the ~~Operations~~fiscal toyear ~~EBITDA~~ended ~~and~~September ~~Adjusted~~30, ~~EBITDA”~~2024. The improvement in operating income for afiscal ~~reconciliation~~2025, compared to the ~~most~~operating ~~directly~~loss ~~comparable~~for Ufiscal 2024, was primarily due to a decrease in impairment losses and lower selling, general and administrative expenses.S. ~~GAAP~~These ~~financial~~positive ~~measure~~effects were partially offset by a decline in gross profit (see Gross Profit and Gross Margin Commentary below) and a decrease in the ~~reasons~~gain wecontingent ~~use~~consideration ~~this~~related ~~non-U.S.~~to ~~GAAP~~the ~~measure~~Fortress acquisition.

~~CONSOLIDATED~~•Diluted ~~RESULTS~~net ~~COMMENTARY:~~loss ~~Fiscal~~per ~~Year~~share ~~Ended~~of ~~September~~$1.91 improved by ~~30,~~$3.08 ~~2024~~from –a ~~Fiscal~~net ~~Year~~loss ~~Ended~~of ~~September~~$4.99 ~~30,~~per ~~2023~~common share in the prior fiscal year period.

~~•Total~~67 ~~sales decreased 7%,~~2025 orFORM $87.3 million, due to lower Salt segment sales, partially offset by sales by the Fortress fire retardant business and higher Plant Nutrition segment sales. The decrease in Salt sales was primarily driven by lower sales volumes, partially offset by higher average sales price. The increase in Plant Nutrition sales from the prior year primarily reflects higher sales volumes, partially offset by lower average sales price. 10-K

•Operating loss of $116.8 million decreased $194.2 million from operating earnings of $77.4 million in the prior fiscal year, reflecting the impairments related to our previous lithium development project (see Item 8, Note 8), our Fortress business and the Plant Nutrition segment (see Item 8, Note 2) and lower Plant Nutrition operating earnings. Corporate and Other operating loss increased from the prior year primarily due to a $74.8 million lithium asset impairment and $50.0 million of goodwill, long-lived asset and inventory impairments related to the Fortress business. The

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~~impairments~~GROSS ~~were~~PROFIT ~~partially~~& ~~offset~~GROSS byMARGIN ~~the~~COMMENTARY: — ~~net~~For ~~non-cash~~the ~~reduction~~Fiscal inYear ~~our~~Ended ~~Fortress-related~~September ~~contingent consideration of $22.1 million. Plant Nutrition operating earnings decreased due primarily to a $51.0 million goodwill impairment~~30, ~~a $17.6 million water rights impairment and lower sales prices~~2025, ~~which~~Compared ~~were~~to ~~partially~~the ~~offset~~Fiscal byYear ~~higher~~Ended ~~sales~~September ~~volumes and lower per-unit distribution costs. In addition~~30, ~~Salt operating earnings decreased slightly due to lower Salt sales volumes, partially offset by higher average sales prices.~~2024

~~•Diluted~~Gross ~~net~~Profit: ~~loss~~Decreased ~~per~~2.2%, ~~share~~or of $4.~~99 decreased by~~3 ~~$5.24~~million; ~~from~~Gross ~~net~~Margin ~~earnings~~decreased ~~of $0~~2.252% ~~per~~from ~~common~~17.5% ~~share~~to ~~in the prior fiscal year period~~15.3%

•EBITDA*Salt ~~adjusted~~segment ~~for~~gross ~~items~~profit ~~management~~decreased ~~believes are not indicative of our ongoing operating performance (“Adjusted EBITDA”)* increased 4%, or~~ $718.29 million, ~~benefiting~~primarily ~~from~~due ato ~~$22.1 million~~lower ~~net~~average ~~gain~~combined ~~recorded~~sales inprices ~~the~~and ~~current~~higher ~~fiscal~~per-unit ~~year~~product ~~period~~costs, ~~related~~partially tooffset ~~the~~by ~~decline~~higher insales ~~the~~volumes ~~valuation~~(see ofSalt ~~the~~operating ~~Fortress contingent consideration~~results).

~~GROSS~~•Gross ~~PROFIT~~profit &for ~~GROSS~~the ~~MARGIN~~Plant ~~COMMENTARY:~~Nutrition ~~Fiscal~~segment ~~Year~~increased ~~Ended~~$23.1 ~~September~~million ~~30,~~due ~~2024~~to –higher ~~Fiscal~~sales ~~Year~~volumes ~~Ended~~and ~~September~~lower 30per-unit product costs, ~~2023~~partially offset by lower average sales prices and higher per-unit distribution costs (see Plant Nutrition operating results).

•Gross ~~Profit:~~profit ~~Decreased~~was ~~16%~~also unfavorably impacted by a reduction in Fortress gross profit, orin ~~$37~~comparison to the prior year.0 ~~million;~~No ~~Gross~~Fortress ~~Margin~~sales ~~decreased~~occurred 2%in ~~from~~fiscal ~~19%~~2025, toand ~~17%~~on May 30, 2025, we completed the sale of the Fortress fire retardant assets.

~~•Salt~~OTHER ~~segment~~EXPENSES ~~gross~~AND ~~profit~~INCOME ~~decreased~~COMMENTARY: ~~$9.1~~— ~~million~~For ~~primarily~~the ~~due~~Fiscal toYear ~~lower~~Ended ~~sales~~September ~~volumes~~30, ~~and higher per-unit product costs~~2025, ~~which~~Compared ~~were~~to ~~partially~~the ~~offset~~Fiscal byYear ~~higher~~Ended ~~average~~September ~~sales~~30, ~~prices (see “—Operating Segment Performance—Salt” for additional information).~~ 2024

~~•Gross~~SG&A: ~~profit for the Plant Nutrition segment decreased~~ Decreased $2824.45 million; ~~due~~Decreased to3.2 ~~lower~~percentage ~~average~~points ~~sales~~as ~~prices,~~a ~~which~~percentage ~~were~~of ~~partially offset by lower per-unit distribution costs and higher~~ sales ~~volumes~~from ~~(see “—Operating Segment Performance—Plant Nutrition” for additional information)~~12.3% to 9.1%

•~~Fortress~~The ~~gross~~decrease ~~profit~~in ~~decreased~~SG&A ~~$1.0~~expense ~~million~~was ~~from~~primarily ~~2023~~due asto ~~Fortress~~reductions ~~was~~in ~~not~~corporate ~~awarded~~compensation aexpense ~~contract~~and ~~for~~professional ~~the 2024 fire season~~services.

~~OTHER~~Loss ~~EXPENSES~~on ~~AND INCOME COMMENTARY~~Impairments: ~~Fiscal~~Decreased ~~Year~~$137.3 ~~Ended~~million ~~September~~to ~~30,~~$53.7 ~~2024 – Fiscal Year Ended September 30, 2023~~ million

~~SG&A:~~•We ~~Decreased~~ recorded a loss on impairment of definite-lived intangible assets and long-lived assets of $1253.47 million;, ~~Decreased~~during ~~0.2~~the ~~percentage~~fiscal ~~points~~year asended aSeptember ~~percentage~~30, of2025, ~~sales~~related to ~~12.3%~~ ~~from~~the 12exit of Fortress.5%

•~~The~~During ~~decrease~~the infiscal ~~SG&A~~year ~~expense~~ended ~~was~~September ~~primarily~~30, ~~due~~2024, towe ~~lower~~recognized ~~corporate~~goodwill ~~expenses,~~impairments ~~including~~of ~~lower~~$51.0 million ~~compensation~~related ~~expenses~~to ~~due~~our toPlant ~~restructuring~~Nutrition segment and ~~lower~~$32.0 million ~~professional~~related ~~services,~~to asour ~~well~~Fortress asoperations ~~lower~~(within ~~lithium~~the ~~expenses~~Corporate and Other segment). ~~These~~The ~~decreases~~Plant ~~were~~Nutrition ~~partially~~impairment ~~offset~~was byprimarily ~~higher~~the ~~expenses~~result of reduced cash flow assumptions impacting expected profitability of the Plant Nutrition segment. The Fortress impairment was primarily related to uncertainty surrounding our ~~Fortress~~magnesium chloride-based fire ~~retardant~~retardants ~~business~~which ~~that~~impacted ~~was~~projected ~~acquired~~future inrevenues ~~May~~and ~~2023~~cash flows. Also, during the fiscal year ended September 30, 2024, we recorded a loss on impairment of definite-lived intangible asset of $15.6 million, related to Fortress magnesium chloride-based products.

~~Loss~~•We recorded a loss on ~~Impairments:~~impairment of long-lived assets of $~~191~~74.0 8 million infor the ~~current-~~fiscal year ~~period~~ended September 30, 2024 related to the termination of the lithium development.

•~~During~~We ~~the~~recorded ~~fiscal~~an ~~year~~impairment ~~ended~~loss ~~September 30, 2024, we recognized goodwill impairments~~ of $5117.06 million ~~related~~for ~~to our Plant Nutrition segment and $32.0 million related to our Fortress operations (within~~ the Corporate and Other segment). The Plant Nutrition impairment was primarily the result of reduced cash flow assumptions impacting expected profitability of the Plant Nutrition segment. The Fortress impairment was primarily related to uncertainty surrounding our magnesium chloride-based fire retardants which impacted projected future revenues and cash flows. Also, during the fiscal year ended September 30, 2024, wein ~~recognized~~our aPlant ~~$15.6 million~~Nutrition ~~long-lived~~segment ~~asset impairment, net,~~ related to ~~Fortress~~water ~~magnesium~~rights ~~chloride~~definite-~~based~~lived ~~products.~~intangible ~~See Item 8, Note 2 for additional information~~asset.

•WeSee ~~recognized~~Item an8, ~~impairment~~Note ~~loss of $74~~2.~~8 million~~ ~~for~~Summary ~~the~~of ~~fiscal~~Significant ~~year~~Policies ~~ended~~of ~~September~~our ~~30,~~Consolidated ~~2024~~Financial ~~related~~Statements tofor ~~the~~additional ~~termination~~information ofon the ~~lithium~~impairment ~~development~~losses ~~(see~~discussed ~~Item 8, Note 8)~~above.

~~•We~~68 ~~recognized~~2025 anFORM ~~impairment loss of $17.6 million for the fiscal year ended September 30, 2024 in our Plant Nutrition segment related to water rights (see Item 8, Note 9).~~10-K

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Other Operating (Income) Expense: ~~Changed~~Decreased $2115.4 million from ~~expense~~income of $417.40 million to income of $171.06 million

•The ~~change~~decrease in other operating (income) ~~expense~~ was primarily ~~the~~due ~~result~~to of a ~~$22.1 million~~decrease ~~non-cash gain~~ in the gain contingent consideration ~~recorded~~of in$14.2 ~~the~~million ~~current fiscal year~~ related to the Fortress acquisition, ~~due~~along towith ~~changes~~an increase in ~~projected~~legal ~~revenues~~fees and ~~cash~~product ~~flows~~recall ~~from~~costs, ~~our~~partially ~~magnesium~~offset ~~chloride-based~~by ~~fire~~the ~~retardants.~~decrease in severance costs and corporate restructuring charges.

~~•The~~Interest ~~other~~Income: ~~operating~~Increased ~~income~~$0.3 ~~was~~million ~~partially~~to ~~offset by a provision for product recall costs of~~ $01.83 million.

~~Interest~~•The ~~Income:~~increase ~~Decreased~~in ~~$4.3~~interest ~~million~~income during the current fiscal year period is primarily due to $1a higher average cash balance in the current year.0 ~~million~~

~~•The~~Interest ~~decrease~~Expense: inDecreased ~~interest~~$1.0 ~~income~~million ~~during the current fiscal year period is primarily due~~ to ~~a higher average cash balance in the prior period resulting from proceeds received from the private placement of our common stock~~$68.5 million

~~Interest~~•The ~~Expense:~~decrease ~~Increased~~was ~~$14.0~~primarily ~~million~~due to ~~$69.5~~lower ~~million~~debt levels in the current fiscal year period.

~~•The~~Gain ~~increase~~(Loss) ~~was~~on ~~primarily~~Foreign ~~due~~Exchange: toChanged ~~higher~~by ~~debt~~$0.8 ~~levels~~million from a $0.7 million loss in the ~~current~~prior fiscal year ~~period~~to $0.1 million gain

~~Loss~~•We onrealized ~~Foreign~~a ~~Exchange:~~foreign ~~Decreased~~exchange bygain of $10.61 million ~~from~~for ~~$2.3~~the ~~million~~fiscal year ended September 30, 2025, compared to a loss of $0.7 million in the prior year, primarily reflecting the translation of our intercompany loans from Canadian dollars to U.S. dollars.

~~•We~~Loss ~~realized~~on aExtinguishment ~~foreign exchange loss~~ of ~~$0.7~~Debt: ~~million for the fiscal year ended September 30, 2024 compared to a loss of~~ $27.36 million in the ~~prior~~current ~~year~~fiscal ~~due primarily to changes in translating our intercompany loans from Canadian dollars to U.S. dollars.~~year

~~Net~~•We ~~Loss~~recorded a loss on extinguishment of debt of $7.6 million in ~~Equity~~the ~~Investees~~fiscal year ended September 30, 2025, comprised of a $3.9 million prepayment premium related to the partial redemption of 6.75% Senior Notes due 2027 (the “2027 Notes”) and a $3.7 million write-off of unamortized deferred financing costs related to the partial redemption of 2027 Notes and repayment of our term loan. See Item 8, Note 10. Long-Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements for additional information.

~~•We~~Other ~~realized~~Expense, aNet: ~~net~~Increased ~~loss in equity investees of~~ $32.1 million ~~in the fiscal year ended September 30, 2023 reflecting our share of losses related~~ to ~~our equity investments~~$4.3 million

~~Gain~~•The ~~from~~increase ~~Remeasurement~~is primarily due to fees paid and the write-off of ~~Equity~~previously ~~Method~~capitalized ~~Investment~~deferred financing costs when we modified our Credit Agreement and entered into the fourth amendment to our Credit Agreement in the current fiscal year.

~~•We~~Income ~~recognized~~Tax aExpense: ~~gain~~Increased of $108.12 million ~~for~~from ~~the~~$17.9 ~~fiscal~~million ~~year ended September 30, 2023 related~~ to ~~our previously held equity investment in Fortress, which was remeasured to fair value upon our full acquisition of the business in May 2023~~$26.1 million

~~Other~~•The ~~Expense,~~increase ~~Net:~~in ~~Decreased~~income ~~$2.1~~tax ~~million~~expense was primarily driven by the increase in foreign book income in the fiscal year ended September 30, 2025, compared to $2the fiscal year ended September 30, 2024.2 ~~million~~Additionally, the majority of the impairments recorded in the fiscal year ended September 30, 2025 and September 30, 2024 were either not tax deductible or the tax benefit was offset by tax expense for a valuation allowance on the related deferred tax asset.

•~~The~~Our ~~change~~effective istax ~~due~~rate of (49%) for the fiscal year ended September 30, 2025 is primarily todriven aby ~~decrease~~the income mix by country with income recognized in foreign jurisdictions offset by losses recognized in the U.S., for which a valuation allowance has been recorded against the U.S. tax benefit carryforward. Additionally, the majority of the impairments recorded in the fiscal year ended September 30, 2025 and September 30, 2024 were either not tax deductible or the tax benefit was offset by tax expense for a valuation allowance on ~~cash~~the ~~flow~~related ~~hedges~~deferred tax asset. See Item 8, Note 8. Income Taxes of our Consolidated Financial Statements for additional information.

~~Income~~•Our ~~Tax~~income ~~Expense~~tax ~~from~~provision ~~Continuing~~for ~~Operations:~~the ~~Increased~~fiscal $0years ended September 30, 2025 and September 30, 2024 differs from the U.8S. ~~million~~statutory rate primarily due to ~~$17~~U.9S. ~~million~~statutory depletion, state income taxes, nondeductible executive compensation, foreign income, mining and withholding taxes and valuation allowance expense.

~~•Income~~OPERATING ~~tax~~SEGMENT ~~expense~~PERFORMANCE: — ~~increased~~For ~~$0.8 million despite a reduction in pretax book income of $215.8 million due primarily to~~ the ~~income~~Fiscal ~~mix~~Year byEnded ~~country~~September ~~with income recognized in foreign jurisdictions more than offset by losses~~30, ~~including significant impairments~~2025, ~~recognized~~Compared into the ~~U.S.,~~Fiscal ~~for~~Year ~~which~~Ended aSeptember ~~valuation~~30, ~~allowance has been recorded against the U.S. tax benefit carryforward. See Note 2 for further discussion of impairments.~~2024

~~•Our~~The ~~effective~~following ~~tax~~financial ~~rate~~results ~~was~~represent aconsolidated ~~negative~~financial ~~10%~~information with respect to sales from our Salt and Plant Nutrition segments for the fiscal ~~year~~years ended September 30, ~~2024,~~2025 ~~which~~and isSeptember ~~primarily~~30, ~~driven~~2024. Sales byprimarily ~~the~~include ~~income~~revenue ~~mix~~from bythe ~~country~~sales ~~with~~of ~~income~~our ~~recognized~~products, inor ~~foreign~~“product ~~jurisdictions~~sales,” ~~more~~and ~~than~~the ~~offset~~impact byof ~~losses~~shipping ~~recognized~~and inhandling ~~the~~costs ~~U.S.,~~incurred ~~for~~to ~~which~~deliver aour ~~valuation~~salt ~~allowance~~and ~~has~~plant ~~been~~nutrition ~~recorded~~products ~~against~~to ~~the~~our Ucustomers.~~S. tax benefit carryforward.~~

~~•Our~~69 ~~income~~2025 ~~tax~~FORM provision in both periods differs from the U.S. statutory rate primarily due to U.S. statutory depletion, state income taxes, nondeductible executive compensation, foreign income, mining and withholding taxes and valuation allowance expense. Additionally, the income tax provision for the fiscal year ended September 30, 2023 included base erosion and anti10-~~abuse tax.~~K

OPERATING SEGMENT PERFORMANCE

The following financial results represent consolidated financial information with respect to sales from our Salt and Plant Nutrition segments for the fiscal years ended September 30, 2024 and 2023. Sales primarily include revenue from the sales of our products, or “product sales,” and the impact of shipping and handling costs incurred to deliver our salt and plant nutrition products to our customers.

The results of operations of the Fortress business include sales of $14.7 million and $10.4 million for the fiscal years ended September 30, 2024 and 2023, respectively. The results of operations of the consolidated records management business and other incidental revenues include sales of $13.9 million, $11.4 million and $11.5 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively. These sales are not material to our consolidated financial results and are not included in the following operating segment financial data.

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The Fortress results of operations include sales of $0.0 million and $14.7 million for the fiscal years ended September 30, 2025 and September 30, 2024, respectively. The results of operations of the consolidated records management business and other incidental revenues include sales of $15.1 million and $13.9 million, for the fiscal years ended September 30, 2025 and September 30, 2024, respectively. These sales are not material to our consolidated financial results and are not included in the following operating segment financial data.

SALT SEGMENT RESULTS

	Fiscal Year Ended
	September 30,2024		September 30,2023		September 30,2022
	September 30,2025		September 30,2024
Salt Sales (in millions)	$	~~907~~1,022.85	$	~~1,010~~907.8	$	~~1,011.4~~
Salt Operating Earnings (in millions)	$	163.6	$	170.5	$	115.6
Salt Operating Income (in millions)	$	145.9	$	163.6
Salt Sales Volumes (thousands of tons)
Highway deicing	78,~~462~~985		97,~~321~~462		~~10,453~~
Consumer and industrial	1,~~852~~863		1,~~999~~852		~~2,122~~
Total tons sold	910,~~314~~848		119,~~320~~314		~~12,575~~
Average Salt Sales Price (per ton)
Highway deicing	$	7371.2353	$	6873.8523	$	~~61.34~~
Consumer and industrial	$	~~195~~203.1487	$	~~184~~195.6714	$	~~174.45~~
Combined	$	9794.4726	$	8997.2947	$	~~80.45~~

SALT SEGMENT RESULTS COMMENTARY: — For the Fiscal Year Ended September 30, ~~2024~~2025, –Compared to the Fiscal Year Ended September 30, ~~2023~~ 2024

•Salt sales of $~~907~~1,022.85 million ~~decreased~~increased $~~103~~114.07 million, or 1012.6%, in the current year reflecting ~~lower~~higher ~~Salt~~sales volumes, ~~which were~~ partially offset by ~~higher~~lower ~~Salt~~highway deicing average sales prices.

•Salt sales volumes ~~decreased~~increased 1816.5%, ~~or 2.0~~increasing ~~million tons, and reduced~~ sales by approximately $~~155~~113.17 million. Highway deicing sales volumes ~~decreased~~increased 20.4% reflecting a ~~combination~~more ofnormal ~~exceptionally~~winter ~~mild~~ weather ~~and~~in the ~~impact~~North ofAmerican 9%deicing ~~lower~~season, ~~total~~compared ~~committed~~to ~~bid~~the ~~volumes~~same ~~year~~period ~~over~~of ~~year compared to~~ the prior~~-year~~ ~~bid season~~year. Consumer and industrial sales volumes ~~decreased~~increased 70.6%, primarily ~~reflecting~~due ato ~~decrease~~higher inconsumer deicing ~~sales~~ volumes.

•~~Salt~~Combined average sales price ~~increased~~decreased ~~9% and contributed approximately $52~~3.~~1 million to the increase in sales~~3%, partially offsetting the ~~decrease~~volume inincrease ~~sales~~by ~~volumes,~~approximately ~~due~~$1.0 million todriven ~~higher~~by ~~highway~~a ~~and~~decrease ~~consumer~~in ~~and~~highway ~~industrial~~ average sales prices.

•Highway deicing average sales prices ~~increased~~decreased 62.3% ~~across all product categories when compared to the prior year as we have sought to restore profitability~~ and ~~offset the impact of prior year inflation on our costs by executing a commercial bidding strategy emphasizing pricing over volume.~~ Consumer and industrial average sales prices increased 64.5%, ~~due~~which toresulted ~~price~~in ~~increases~~a ~~taken~~combined toaverage ~~offset~~sales ~~inflation~~price ~~realized~~decrease inof 3.3%, compared to the prior ~~years~~year. The ~~higher~~lower combined average sales prices are also reflective of sales mix.

•Salt operating ~~earnings~~income decreased 410.8%, or $617.97 million, due primarily to lower ~~sales~~combined ~~volumes~~average ~~for~~sales ~~both~~prices ~~highway~~ and ~~consumer and industrial products and~~ higher per-unit product costs, ~~which were~~ partially offset by higher ~~average~~ sales ~~prices~~volumes and lower per-unit distribution costs.

PLANT NUTRITION RESULTS

	Fiscal Year Ended
	September 30,2024		September 30,2023		September 30,2022
	September 30,2025		September 30,2024
Plant Nutrition Sales (in millions)	$	~~181~~206.03	$	~~172~~181.10	$	~~222.3~~
Plant Nutrition Operating (Loss) Earnings (in millions)	$	(86.4)	$	9.5	$	40.2
Plant Nutrition Operating (Loss) Income (in millions)	$	6.5	$	(86.4)
Plant Nutrition Sales Volumes (thousands of tons)	~~273~~326		~~219~~273		~~286~~
Plant Nutrition Average Sales Price (per ton)	$	~~663~~634	$	~~785~~663	$	~~777~~

PLANT NUTRITION RESULTS COMMENTARY: — For the Fiscal Year Ended September 30, ~~2024~~2025, –Compared to the Fiscal Year Ended September 30, ~~2023~~ 2024

•Plant Nutrition sales increased 514.0%, or $825.93 million, due to higher sales volumes, ~~which was~~ partially offset by lower average ~~sales prices.~~

~~•Plant~~70 ~~Nutrition~~2025 ~~sales~~FORM volumes increased 25%, or 54,000 tons, which contributed approximately $42.4 million to the increase in sales driven by normalization of demand levels in fiscal 2024 following lower demand in fiscal 2023 reflective of impacts from weather events in key markets and uncertainty regarding future fertilizer prices causing customers to cancel or delay purchases. 10-K

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~~•Plant Nutrition~~ sales prices ~~decreased 16%, partially offsetting the increase in sales by approximately $33~~.~~5 million. Average sales prices decreased through fiscal 2024 due to global supply and demand dynamics for fertilizer products resulting in weakening pricing year over year.~~

•Plant Nutrition ~~operating~~sales ~~earnings decreased~~volumes ~~$95~~increased 19.94%, ~~million~~or 53,000 tons, towhich anresulted ~~operating loss of $86.4 million~~ in ~~fiscal 2024 primarily due to~~ a $5135.~~0 million goodwill impairment, a $17.6~~1 million ~~water~~increase ~~rights~~in ~~impairment~~sales ~~and~~driven ~~lower~~by ~~sales~~positive ~~prices,~~production ~~which~~trends ~~were~~in ~~partially~~2025 ~~offset~~that byhave ~~higher~~allowed ~~sales~~us ~~volumes~~to ~~and~~pursue ~~lower~~business ~~per-unit~~beyond ~~distribution~~normally ~~costs~~serviced markets.

~~OUTLOOK~~•Plant Nutrition average sales prices decreased 4.4%, partially offsetting the increase in sales volume by $9.8 million.

•~~Following~~Plant ~~one~~Nutrition ofoperating ~~weakest~~income ~~winters~~ in ~~our served markets in nearly a quarter century, committed volumes for~~ fiscal year 2025 inwas ~~the~~$6.5 ~~North~~million, ~~American~~compared ~~highway~~to ~~deicing~~an ~~business~~operating ~~are~~loss ~~down~~of ~~approximately 9%~~$86.4 ~~Despite~~million ~~these~~in ~~lower~~fiscal ~~volume~~year ~~commitments,~~2024. weThe ~~expect~~improvement ~~Salt~~in ~~segment~~earnings ~~sales~~was ~~volumes~~due to ~~increase~~higher bysales ~~approximately~~volumes 9%combined ~~year~~with ~~over year at~~ the ~~mid-point~~prior ofyear ~~our~~including ~~guidance range based on a reversion to more normalized weather~~$68.6 ~~Pricing~~million ~~for~~loss ~~the~~from ~~Salt~~impairments ~~segment~~(goodwill isand ~~expected~~water ~~to decline slightly year over year~~rights), ~~driven~~partially offset by lower ~~North American highway deicing bid season results that saw~~ average ~~pricing contract due to excess supply across the system. Accordingly, we expect Salt segment~~ sales ~~volumes~~prices and ~~adjusted~~higher ~~EBITDA~~per-unit todistribution ~~range from 9~~costs.7 ~~million to 10.7 million tons and $225 million to $250 million, respectively, in fiscal year 2025.~~

~~•Plant~~Results ~~Nutrition segment sales volumes are expected to improve to a range~~ of ~~285,000~~Operations—For tothe ~~305,000~~Fiscal ~~tons~~Year inSeptember ~~fiscal year 2025~~30, ~~improving from levels in fiscal year~~ 2024, ~~that~~Compared ~~reflected a return~~ to ~~normal~~the ~~demand~~Fiscal inYear ~~core~~September ~~Western markets. We expect lower average selling prices throughout fiscal 2025 due to anticipated weakness in global potash value. For fiscal year 2025~~30, ~~we expect adjusted EBITDA in a range of $14 million to $20 million.~~2023

~~•Fiscal~~For a discussion and analysis of the fiscal year ~~2025~~ended ~~capital~~September ~~expenditures~~30, ~~are~~2024, ~~expected~~compared to bethe infiscal ~~the~~year ~~$100~~ended ~~million~~September to30, ~~$110~~2023, ~~million~~see ~~range~~“Part II, Item 7. ~~This~~Management’s ~~includes~~Discussion ~~non-recurring~~and ~~amounts~~Analysis of ~~approximately~~Financial ~~$10~~Condition ~~million~~and toResults ~~$15~~of ~~million~~Operations” ~~related~~of toour ~~larger~~Form ~~capital~~10-K ~~projects,~~for ~~including~~the ~~preparation~~fiscal ~~work~~year ~~for~~ended September 30, 2024, filed with the ~~mill~~SEC ~~relocation~~on atDecember ~~Goderich~~16, ~~mine~~2024, ~~and~~which ~~refurbishment~~is ofincorporated ~~silos~~herein atby ~~Ogden~~reference.

~~Investments,~~ Liquidity and Capital Resources—For the Fiscal Year Ended September 30, 2025, Compared to the Fiscal Year Ended September 30, 2024

~~Overview~~Historically, our cash flows from operating activities have generally been adequate to fund our basic operating requirements, ongoing debt service and sustaining investment in our property, plant and equipment. We have also used cash generated from operations to fund capital expenditures, pay dividends, fund smaller acquisitions and repay our debt. To a certain extent, our ability to meet our short- and long-term liquidity and capital needs is subject to general economic, financial, competitive and weather conditions, effects of climate change, geological variations in our mine deposits and other factors that are beyond our control. Historically, our working capital requirements have been the highest in the first fiscal quarter (ending December 31) and lowest in the third fiscal quarter (ending June 30). When needed, we may fund short-term working capital requirements by accessing our $325 million revolving credit facility and our revolving AR Securitization Facility extending to March 2027 with a capacity, which is subject to certain conditions, of up to $100.0 million. As of September 30, 2025, we had liquidity of approximately $364.6 million, comprised of $59.7 million of cash and cash equivalents and $304.9 million of availability under our $325 million revolving credit facility.

AsPrincipally adue ~~holding~~to ~~company,~~the ~~CMI’s~~nature ~~investments~~of inour ~~its~~deicing ~~operating~~business, ~~subsidiaries~~our ~~constitute~~cash ~~substantially~~flows ~~all~~from ofoperations ~~its~~have ~~assets.~~historically ~~Consequently~~been seasonal, ~~our~~with ~~subsidiaries~~the ~~conduct~~majority ~~all~~ of our ~~consolidated~~cash flows from operations ~~and~~generated ~~own~~during ~~substantially~~the ~~all~~first half of ~~our~~the ~~operating~~calendar ~~assets~~year (see “—Seasonality” for more information). Our ~~The~~working ~~principal~~capital ~~source~~needs ofare ~~cash~~heavily ~~needed~~impacted toby ~~pay~~the ~~our~~severity ~~obligations~~and istiming of the ~~cash~~winter ~~generated~~weather, ~~from~~which ~~our~~generally ~~subsidiaries’~~occurs ~~operations~~from ~~and~~December ~~their~~through ~~borrowings~~March each year. ~~Furthermore,~~Customers wetend ~~must~~to ~~remain~~replenish intheir ~~compliance~~inventory ~~with~~prior to the ~~terms~~start of the ~~credit~~winter ~~agreement~~season ~~governing~~and ~~our~~following ~~credit~~snow ~~facilities~~events, ~~including~~consequently the ~~consolidated~~number ~~total~~and ~~net~~timing ~~leverage~~of ~~ratio~~snow ~~and~~events ~~interest~~during ~~coverage~~the ~~ratio. We~~winter ~~must~~season ~~also~~will ~~comply~~impact ~~with~~ the ~~terms~~amount of our ~~indentures~~accounts ~~governing~~receivable ~~our~~and 6inventory at the end of each quarter.~~75%~~ ~~Senior~~When ~~Notes~~we ~~due~~have ~~December~~not ~~2027~~been ~~(the~~able ~~“6.75%~~to ~~Notes”)~~meet our short-term liquidity or capital needs with cash from operations, ~~which~~whether ~~limits~~as a result of the ~~amount~~seasonality of ~~dividends~~our business or other causes, we ~~can~~have ~~pay~~met tothose needs with borrowings under our ~~stockholders~~revolving credit facility. We ~~are~~expect into ~~compliance~~meet ~~with~~the ~~our~~ongoing requirements for debt ~~covenants~~service, asany ofdeclared ~~September 30,~~dividends ~~2024~~and capital expenditures from these sources. ~~See~~This, ~~Item~~to 8a certain extent, ~~Note~~is 12subject to ~~our~~general ~~Consolidated~~economic, ~~Financial~~financial, ~~Statements~~competitive, ~~for~~legislative, aregulatory ~~discussion~~and ofother ~~our~~factors ~~outstanding~~that ~~debt~~are beyond our control.

~~Historically,~~We manage our ~~cash~~capital ~~flows~~allocation ~~from~~considering ~~operating~~our ~~activities~~long-term ~~have~~strategic ~~generally~~objectives, ~~been~~required ~~adequate~~spending to ~~fund~~sustain our ~~basic~~business ~~operating requirements, ongoing debt service~~ and ~~sustaining~~focus ~~investment~~on ingenerating ~~our~~adequate ~~property,~~returns ~~plant~~on ~~and equipment~~capital. We ~~have~~On ~~also~~April ~~used cash generated from operations to fund capital expenditures~~22, ~~pay dividends~~2024, ~~fund~~the ~~smaller~~Board ~~acquisitions~~of ~~and~~Directors ~~repay~~determined ~~our~~not ~~debt. We have been able~~ to ~~manage~~declare ~~our~~dividends ~~cash~~for ~~flows~~the ~~generated~~foreseeable ~~and~~future ~~used~~in ~~across~~order ~~Compass Minerals~~ to ~~indefinitely~~align ~~reinvest earnings in~~ our ~~foreign~~capital ~~jurisdictions~~allocation orpriorities ~~efficiently~~with ~~repatriate~~our ~~those~~corporate ~~funds~~focus toon ~~the~~accelerating ~~U.S. As~~cash offlow ~~September 30,~~generation ~~2024,~~and wedebt ~~had $17~~reduction.3 ~~million~~While ofour ~~cash~~equipment and ~~cash~~facilities ~~equivalents~~are ~~(in~~generally ~~our~~not ~~Consolidated~~impacted ~~Balance~~by ~~Sheets)~~rapid ~~that~~technology ~~was~~changes, ~~either~~our ~~held~~operations ~~directly~~require orrefurbishments ~~indirectly~~and byreplacements ~~foreign~~to ~~subsidiaries. Due~~maintain instructural ~~large~~integrity ~~part~~and toreliable ~~the~~production ~~seasonality~~and ofshipping ~~our~~capabilities. ~~salt~~When ~~deicing business~~possible, we ~~have~~incorporate ~~experienced~~efficiency, ~~large~~environmental ~~changes~~and insafety ~~our~~improvements ~~working~~into ~~capital requirements from quarter to quarter. Historically,~~ our ~~working~~routine capital ~~requirements~~projects ~~have been the highest in the first fiscal quarter (ending December 31)~~ and ~~lowest~~we inplan the ~~third~~timing ~~fiscal~~of ~~quarter~~larger ~~(ending~~projects ~~June~~to ~~30). When~~balance ~~needed,~~with weour ~~may~~liquidity ~~fund~~and ~~short-term working~~ capital ~~requirements~~resources. byChanges ~~accessing~~in our ~~$375~~operating ~~million~~cash ~~revolving~~flows ~~credit~~may ~~facility~~affect ~~and~~ our ~~$100~~future ~~million~~capital ~~revolving~~allocation ~~accounts~~and ~~receivable financing facility (our “AR Facility”)~~spending.

~~Notwithstanding~~We ~~our~~have ~~strategic~~been ~~decision~~able to ~~exit~~manage our ~~South~~cash ~~America~~flows ~~chemicals~~generated and ~~specialty~~used ~~plant~~across ~~nutrition~~Compass ~~businesses,~~Minerals ~~as discussed in Item 8, Note 1 and Note 4~~ to ~~our~~indefinitely ~~Consolidated~~reinvest ~~Financial statements, we have historically considered the undistributed~~ earnings ofin our foreign ~~subsidiaries~~jurisdictions toor beefficiently ~~permanently~~repatriate ~~reinvested.~~those Asfunds ato ~~result~~the of U.S. As ~~tax~~of ~~reform~~September 30, 2025, we ~~revised~~had ~~our permanently reinvested assertion in fiscal 2018 expecting to repatriate approximately~~ $~~150~~23.6 million of ~~unremitted~~cash ~~foreign~~and ~~earnings~~cash ~~from~~equivalents ~~Canada.~~(in ~~In fiscal 2022, we revised~~ our ~~permanently~~Consolidated ~~reinvested~~Balance ~~assertion,~~Sheets) ~~expecting~~that towas ~~repatriate~~either anheld ~~additional~~directly ~~$10~~or ~~million~~indirectly ofby ~~unremitted~~ foreign ~~earnings~~subsidiaries. ~~from~~In ~~our~~fiscal ~~U.K.~~2025 ~~operations~~ and in fiscal ~~2023~~2024, we ~~revised~~did itnot ~~again expecting to~~ repatriate anany ~~additional approximately $6 million of~~ unremitted foreign earnings ~~from our U~~.K. ~~operations.~~ During the ~~first~~second quarter of fiscal ~~2023~~2025, ~~$89.2~~we ~~million~~revised ~~was~~our ~~repatriated~~permanently ~~from~~reinvested Canada and in the third quarter of fiscal 2023, $15.6 million was repatriated from the U.K. Net income tax expense of $3.8 million has been recorded for foreign withholding tax, state income tax and foreign exchange losses on these changes in assertion ~~as of September 30, 2024, consisting of a tax benefit of $0~~.7 ~~million~~We ~~recorded~~are inexpecting ~~fiscal~~to ~~2023,~~repatriate aapproximately ~~tax benefit of~~ $~~0.2~~11 ~~recorded in fiscal 2022 and tax expense of $4.7~~ million, ~~recorded in years prior to fiscal 2022. It is our current intention to continue to reinvest the remaining undistributed earnings~~ of ~~our~~unremitted foreign ~~subsidiaries indefinitely.~~

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Weearnings ~~review~~from our ~~tax~~UK ~~circumstances~~operations on awhich ~~regular~~there ~~basis~~was ~~with~~no ~~the~~income ~~intent~~tax impact as of ~~optimizing~~September ~~cash~~30, ~~accessibility~~2025. ~~and~~It ~~minimizing~~is ~~tax~~our ~~expense.~~current Asintention ofto ~~September 30,~~continue ~~2024,~~to wereinvest ~~have~~the ~~$213.5~~remaining ~~million~~undistributed earnings of ~~outside~~our ~~basis~~foreign ~~differences~~subsidiaries ~~for~~indefinitely. ~~which~~We noreview ~~deferred~~our ~~taxes~~tax ~~have~~circumstances ~~been~~on ~~recorded.~~a ~~See~~regular ~~Item~~basis 8,with ~~Note~~the 10intent toof ~~our~~optimizing ~~Consolidated~~cash ~~Financial~~accessibility ~~Statements~~and ~~for~~minimizing ~~additional~~tax ~~information~~expense.

In addition, the amount of permanently reinvested foreign earnings is influenced by, among other things, the profits generated by our foreign subsidiaries and the amount of investment in those same subsidiaries. The profits generated by our U.S. and foreign subsidiaries are impacted by the transfer price charged on the transfer of our products between them. As ~~discussed in Item 8, Note 10 to our Consolidated Financial Statements,~~ Canadian provincial taxing authorities continue to challenge our transfer prices of certain items. The final resolution of these challenges may not occur for several years. We currently expect the outcome of these matters will not have a material impact on our results of operations. However, it is possible the resolution could materially impact the amount of earnings attributable to our foreign subsidiaries, which could impact the amount of permanently reinvested foreign earnings. See Item 8, Note 108. toIncome Taxes and Note 18. Subsequent Event of our Consolidated Financial Statements for a discussion regarding our Canadian tax reassessments.

~~Capital~~Historical ~~Allocation~~Cash Flows

~~Principally~~The ~~due~~table tobelow ~~the~~provides nature of our deicing business, our cash flows from operations have historically been seasonal, with the majority of our cash flows from operations generated during the first half of the calendar year (see “—Seasonality” for more information). When we have not been able to meet our short-term liquidity or capital needs with cash from operations, whether as a ~~result~~summary of ~~the seasonality of~~ our business or other causes, we have met those needs with borrowings under our revolving credit facility. We expect to meet the ongoing requirements for debt service, any declared dividends and capital expenditures related to our Salt, Plant Nutrition and Fortress businesses from these sources. ~~This, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory~~ and ~~other~~uses ~~factors~~of ~~that~~cash ~~are~~(in ~~beyond our control.~~millions):

We manage our capital allocation considering our long-term strategic objectives, required spending to sustain our business and focus on generating adequate returns on capital. In April 2024, the Board of Directors determined not to declare dividends for the foreseeable future in order to align the Company’s capital allocation priorities with its corporate focus on accelerating cash flow generation and debt reduction. While our equipment and facilities are generally not impacted by rapid technology changes, our operations require refurbishments and replacements to maintain structural integrity and reliable production and shipping capabilities. When possible, we incorporate efficiency, environmental and safety improvements into our routine capital projects and we plan the timing of larger projects to balance with our liquidity and capital resources. Changes in our operating cash flows may affect our future capital allocation and spending.


	Fiscal Year Ended
	September 30, 2025		September 30, 2024
Net cash flow from operating activities	197.7		$	14.4
Net cash flow from investing activities	(50.0)		(116.1)
Net cash flow from financing activities	(108.3)		83.1
Effect of exchange rate changes on cash and cash equivalents	0.1		0.1
Net change in cash and cash equivalents	$	39.5	$	(18.5)

OnAs ~~October~~of 18September 30, ~~2022~~2025, we ~~received~~had ~~aggregate~~cash ~~net~~and ~~proceeds~~cash equivalents of ~~approximately~~ $~~240~~59.7 million, ~~net~~an ofincrease ~~transaction costs, from Koch Minerals & Trading, LLC (“KM&T”) as part~~ of ~~a strategic equity partnership~~$39.5 ~~We have used, or committed to use, approximately $78~~ million ~~of the proceeds~~ from ~~the~~September ~~private~~30, ~~placement for capital expenditures to advance the first development phase of the lithium project with the remainder of the proceeds used to reduce debt or for general corporate purposes~~2024.

InCash ~~fiscal~~Flows ~~2022,~~from weOperating made an additional $45 million equity investment in Fortress, resulting in a total investment of $50 million representing a 45% ownership interest. Fortress is a fire retardant company working to develop long-term fire retardant solutions to help combat wildfires. On May 5, 2023, we acquired the remaining 55% interest in Fortress not previously owned in exchange for an initial cash payment of approximately $18.9 million (net of cash held by Fortress of $6.5 million), and additional contingent consideration of up to $28 million to be paid in cash and/or Compass Minerals common stock upon the achievement of certain performance measures, and a cash earn-out based on financial performance and volumes of Fortress fire retardant products sold over a 10-year period. Building upon the previous 45% minority ownership stake in Fortress, the transaction provided us full ownership of all Fortress assets, contracts, and intellectual property. Activities

69Net cash provided by operating activities, as reflected in the Consolidated Statements of Cash Flows, were $197.7 million, for the fiscal year ended September 30, 2025, as compared to $14.4 million, for the fiscal year ended September 30, 2024. ~~FORM~~Throughout 10the fiscal year ended September 30, 2025, we realized a working capital release of approximately $117 million out of finished goods inventory as part of our back-Kto-basics strategy of optimizing inventory volumes and associated cash impacts. In addition, the increase in cash flows provided by operating activities for the fiscal year ended September 30, 2025, included increases in accounts payable and accrued expenses, partially offset by increases in receivables.

Cash flows from Investing Activities

Net cash used in investing activities, as reflected in the Consolidated Statements of Cash Flows, were $50.0 million and $116.1 million, during the fiscal years ended September 30, 2025 and September 30, 2024, respectively. Cash outflows from investing activities for capital expenditures during the fiscal years ended September 30, 2025 and September 30, 2024 were $69.7 million and $114.2 million, respectively. The decrease in investing activities for capital expenditures during the fiscal year ended September 30, 2025, was primarily due to the termination of the lithium development project in the prior year. During the fiscal year ended September 30, 2025, we received proceeds from the sale of Fortress assets, net of transaction costs of $19.6 million. We estimate that our cash outflows for capital expenditures will be approximately $90 million to $110 million for the fiscal year ended September 30, 2026.

Cash Flows from Financing Activities

Net cash used in financing activities, as reflected in the Consolidated Statements of Cash Flows, were $108.3 million, for the fiscal year ended September 30, 2025, as compared to net cash provided in financing activities of $83.1 million, for the fiscal year ended September 30, 2024. The decrease in cash flows from financing activities during the fiscal year ended September 30, 2025, compared to September 30, 2024, was primarily due to the principal and redemption premium under our 2027 Notes


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~~The~~and ~~table~~repayment ~~below~~of ~~provides~~our aRevolving ~~summary~~Credit ~~our~~Facility ~~cash~~and ~~flows~~Term Loan, partially offset by ~~category~~borrowings under the issuance of our 2030 Notes and ~~period~~Revolving Credit Facility. The Company paid deferred financing fees of $15.9 million and $2.1 million, during the fiscal years ended September 30, 2025 and September 30, 2024, respectively.

Fiscal Year Ended
September 30, 2024	September 30, 2023	September 30, 2022
Operating Activities:
Net cash flows provided by operating activities were $14.4 million.»Net losses were $206.1 million.»Non-cash depreciation and amortization expense was $105.0 million.»Non-cash impairment losses were $191.0 million.»Non-cash stock-based compensation was $8.1 million.»Non-cash net gain from remeasurement of contingent consideration was $22.1 million.»Working capital items were a use of operating cash flows of $66.9 million.	Net cash flows provided by operating activities were $106.0 million.»Net earnings were $10.5 million.»Non-cash depreciation and amortization expense was $98.6 million.»Non-cash stock-based compensation was $20.6 million.»Non-cash remeasurement gain of $10.1 million related to the acquisition of Fortress.»Non-cash loss on disposition of assets was $4.5 million.»Non-cash net loss in equity investees was $3.1 million.»Working capital items were a use of operating cash flows of $22.6 million.	Net cash flows provided by operating activities were $120.4 million.»Net losses were $21.1 million.»Non-cash depreciation and amortization expense was $112.8 million.»Non-cash impairment loss was $23.1 million.»Non-cash stock-based compensation was $15.7 million.»Non-cash net loss in equity investees was $5.2 million.»Non-cash loss on disposition of assets was $3.7 million.»Working capital items were a use of operating cash flows of $11.3 million.
Investing Activities:
Net cash flows used in investing activities were $116.1 million.»Net cash flows used in investing activities included $114.2 million of capital expenditures.	Net cash flows used in investing activities were $177.9 million.»Net cash flows used in investing activities included $154.3 million of capital expenditures. »Included cash investment of $18.9 million, net of cash held by Fortress, for the acquisition of the remaining interest in Fortress.	Net cash flows used in investing activities were $79.9 million.»Net cash flows used in investing activities included $96.6 million of capital expenditures. »Investing activity outflows were partially offset by proceeds of $61.2 million from the sale of our South America specialty chemicals business and specialty plant nutrition earnout. »Included investments in equity method investees of $46.3 million.
Financing Activities:
Net cash flows provided by financing activities were $83.1 million.»Net proceeds from the issuance of debt of $111.6 million.»Included payments of dividends of $12.6 million.»Included payment of contingent consideration of $9.1 million.»Included payment of deferred financing costs of $2.1 million.	Net cash flows provided by financing activities were $64.0 million.»Included payments of dividends of $24.9 million.»Net payments on our debt of $144.7 million.»Included payment of deferred financing costs of $3.9 million.»Included net proceeds from private placement of common stock of $240.7 million.	Net cash flows used in financing activities were $14.3 million.»Included payments of dividends of $20.8 million.»Net proceeds from the issuance of debt of $9.9 million.

As mentioned above, our Salt segment’s business is seasonal and our Salt segment results and working capital needs are heavily impacted by the severity and timing of the winter weather, which generally occurs from December through March each year. Customers tend to replenish their inventory prior to the start of the winter season and following snow events, consequently the number and timing of snow events during the winter season will impact the amount of our accounts receivable and inventory at the end of each quarter. During the fiscal year ended September 30, 2024, we also paid liabilities accrued as of September 30, 2023, including the remaining $10 million settlement payment to the SEC, accrued incentive compensation, and other liabilities. Additionally, at the end of Fortress’ contract term with the USFS, we recognized revenue previously deferred in accrued liabilities and decreased our contingent consideration liability due to recent revisions of potential payouts. The lower accounts receivable balance and higher inventory balance as of September 30, 2024, as compared to September 30, 2023,

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Table of Contents COMPASS MINERALS INTERNATIONAL, INC.

primarily reflects lower sales volumes in the fourth quarter in our Salt segment year over year. The lower accounts receivable balance and higher inventory balance as of September 30, 2023, as compared to September 30, 2022, primarily reflects lower sales volumes in the fourth quarter 2023 in our Salt and Plant Nutrition segments. The acquisition of Fortress resulted in an increase in current liabilities due to accrued contingent consideration and deferred revenue recorded on its contract with the USFS as of September 30, 2023 as compared to September 30, 2022.

Capital Resources

With regard to our Salt, and Plant Nutrition ~~and Fortress~~ businesses, we believe our ongoing primary sources of liquidity will continue to be cash flow from operations and borrowings under our revolving credit facility. We believe that our current banking syndicate is secure and believe we will have access to our entire revolving credit facility. We expect that ongoing requirements for debt service and sustaining capital expenditures will primarily be funded from these sources.

~~Our~~As debt service obligations could, under certain circumstances, materially affect our financial condition and prevent us from executing our business strategies. See Item 1A, “Risk Factors—Our indebtedness and any inability to pay our indebtedness could adversely affect our business and financial condition.” Furthermore, CMI is a holding company with no operations of ~~its own and is dependent on its subsidiaries for cash flow. As discussed in Item 8, Note 12 to our Consolidated Financial Statements, at~~ September 30, ~~2024~~2025, we had $~~922~~845.8 million of outstanding indebtedness consisting of $~~500~~650.0 million outstanding under our 68.7500% Senior Notes due 2030, $~~383~~150.90 million ~~of borrowings~~ outstanding under our ~~senior~~6.75% ~~secured~~Notes ~~credit~~due ~~facilities~~2027, ~~(consisting of a term loan~~ and ~~a revolving credit facility), including~~ $~~190~~45.18 million ~~borrowed~~outstanding ~~against~~loans ~~our~~under ~~revolving~~the ~~credit~~AR ~~facility~~Securitization Facility. ~~Letters~~ Outstanding letters of credit totaling $1520.2 1 million as of September 30, ~~2024,~~2025 further reduced available borrowing capacity under the revolving credit facility to $~~169~~304.7 9 million.

OnWe ~~March~~may ~~27,~~borrow ~~2024,~~amounts weunder ~~entered into an amendment to our 2023 Credit Agreement, which eased~~ the ~~restrictions~~revolving ofcredit ~~certain~~facility ~~covenants~~or ~~contained~~enter ininto ~~the~~additional ~~agreement.~~financing ~~The~~to ~~amendment~~fund ~~included~~our ~~increasing~~working ~~the~~capital ~~maximum~~requirements, ~~allowed~~potential ~~consolidated~~acquisitions ~~total net leverage ratio (as defined~~ and ~~calculated~~capital ~~under the terms of the amended 2023 Credit Agreement) to 6.5x as of the last day of any quarter through the fiscal quarter ended December 31~~expenditures, ~~2024,~~and ~~then~~for ~~gradually~~other ~~stepping~~general ~~down~~corporate ~~to 4~~purposes.~~75x by the fiscal quarter ended March 31, 2026 and thereafter.~~

OnOur ~~August~~ability ~~12,~~to ~~2024,~~make wescheduled ~~entered~~interest ~~into~~and ~~amendments~~principal payments on our indebtedness, to modify our ~~2023~~indebtedness, ~~Credit~~to ~~Agreement~~fund planned capital expenditures, and to fund acquisitions will depend on our ARability ~~Securitization~~to ~~Facility,~~generate ~~which~~cash ~~extended~~in the ~~deadline~~future. ~~for~~This, ~~delivery~~to ofa ~~our~~certain ~~financial~~extent, ~~statements~~is ~~for~~subject ~~the~~to ~~quarter~~general ~~ended~~economic, ~~June~~financial, 30competitive, ~~2024~~legislative, ~~together~~climate-related, ~~with~~regulatory ~~the~~and ~~respective~~other ~~compliance~~factors ~~certificates~~that are beyond our control. Based on our current level of operations, ~~from~~we 45believe ~~days~~that tocash 75flow ~~days~~from ~~after~~operations ~~the~~and ~~last~~available ~~day~~cash, oftogether ~~the~~with ~~quarter~~available ~~ended~~borrowings ~~June~~under 30our revolving credit facility, ~~2024~~will be adequate to meet our liquidity needs over the next 12 months.

OnOur ~~September~~debt ~~13,~~service ~~2024~~obligations could, weunder ~~entered~~certain ~~into~~circumstances, ~~amendments~~materially toaffect our ~~2023~~financial ~~Credit~~condition ~~Agreement~~ and prevent us from fulfilling our ARdebt ~~Securitization~~obligations. ~~Facility~~As a holding company, ~~which~~CMI’s ~~extended~~investments ~~the~~in ~~deadline~~its ~~for~~operating ~~delivery~~subsidiaries constitute substantially all of its assets. Consequently, our ~~financial~~subsidiaries ~~statements~~conduct ~~for~~substantially all of our consolidated operating activities and own substantially all of our operating assets. The principal source of the ~~quarter~~cash ~~ended~~needed ~~June~~to ~~30,~~pay ~~2024~~our obligations is the cash generated from our subsidiaries’ operations and their borrowings. Furthermore, ~~together~~we must remain in compliance with the ~~respective~~terms ~~compliance~~of ~~certificates,~~the to2023 ~~November~~Credit 29Agreement governing our credit facilities, ~~2024~~including the consolidated first lien net leverage ratio and consolidated interest coverage ratio, ~~152~~in ~~days~~order ~~after~~to ~~the~~pay ~~last~~dividends ~~day~~to ofour stockholders. We must also comply with the ~~quarter~~terms ~~ended~~of our indentures governing our 6.75% Senior Notes due December 2027 and our 8.00% Senior Notes due June 302030, ~~2024~~which limit the amount of dividends we can pay to our stockholders.

On June 16, 2025, we issued $650.0 million aggregate principal amount of our 8.00% Senior Notes due 2030 in a private offering, pursuant to an indenture, dated June 16, 2025 (the “2030 Notes”), among us, the subsidiary guarantors named therein and Computershare Trust Company, N.A., as trustee. The 2030 Notes are senior unsecured obligations, with interest payable semi-annually on January 1 and July 1, commencing January 1, 2026. The Notes are guaranteed by certain of our domestic subsidiaries. The 2030 Notes will mature on June 16, 2030. We incurred $13.0 million in deferred financing costs, including arrangement, legal and other fees, and will be amortized to interest expense method over the 5-year term of the 2030 Notes.

We used the net proceeds from the 2030 Notes to (i) repay all outstanding amounts under its senior secured credit facility, including $43.5 million under the revolving credit facility and $191.3 million under our term loan, (ii) redeem approximately $350.0 million of its outstanding 2027 Notes at a redemption price of 101.125% of the principal amount, plus accrued and unpaid interest, (iii) pay transaction-related fees and expenses, (iv) increase cash on its balance sheet, and (v) for general corporate purposes. The redemption, completed on June 17, 2025, resulted in a loss on debt extinguishment of $5.7 million, included in Loss on extinguishment of debt in the Consolidated Statements of Operations for the fiscal year ended September 30, 2025. The loss was comprised of a $3.9 million prepayment premium and a $1.8 million write-off of unamortized deferred financing costs. Following the redemption, $150.0 million of the 2027 Notes remain outstanding and continue to accrue interest, payable semi-annually on June 1 and December 1, with unamortized deferred financing costs of $0.7 million as of September 30, 2025.


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On June 16, 2025, we entered into the fifth amendment to its 2023 Credit Agreement, originally dated April 20, 2016, as amended (the “Amended and Restated 2023 Credit Agreement”). The amendment, among other things, (i) fixed the aggregate revolving commitments at $325.0 million, eliminating the automatic periodic step-downs previously included in the December 12, 2024, amendment to the 2023 Credit Agreement, which had scheduled reductions to $250.0 million by July 1, 2026, (ii) permitted the issuance of the 2030 Notes, with net proceeds used to prepay all outstanding loans under the Existing Amended and Restated Credit Agreement, including $43.5 million outstanding under the revolving credit facility and $191.3 million outstanding under our term loan, plus accrued and unpaid interest, (iii) permitted the Company to utilize certain baskets under covenants restricting the incurrence of indebtedness, liens, investments, dividends, and junior debt prepayments, and (iv) modified the financial maintenance covenants, which are tested on a quarterly basis, as follows: (A) replaced the leverage-based covenant, which previously required compliance with a maximum ratio of consolidated total net indebtedness to consolidated EBITDA of 6.50x (with a step-down to 5.75x on December 31, 2025, and a further step-down to 4.75x on March 31, 2026) with a leverage-based covenant which requires compliance with a maximum ratio of consolidated first lien net indebtedness to consolidated EBITDA of 2.75x (with a step-down to 2.50x on December 31, 2025) and (B) lowered the required minimum ratio of consolidated EBITDA to consolidated interest expense from 2.00x (with a step-up to 2.25x on March 31, 2026) to 1.50x. Consolidated first lien net debt includes the aggregate principal amount of consolidated first lien debt, net of unrestricted cash not to exceed $100.0 million. In connection with the prepayment of our term loan, we recorded a loss on debt extinguishment of $1.9 million, included in Loss on extinguishment of debt on the Consolidated Statements of Operations for the fiscal year ended September 30, 2025, related to the write-off of unamortized deferred financing costs related to this instrument. As of September 30, 2025, our consolidated first lien net leverage ratio was approximately 0.01x.

On December 12, 2024, we entered into the fourth amendment to our 2023 Credit Agreement, which, among other things, eased the restrictions of certain covenants contained in the agreement. The amendment included increasing the maximum allowed consolidated total net leverage ratio (as defined and calculated under the terms of the amended 2023 Credit Agreement) to 6.5x as of the last day of any quarter through the fiscal quarter ended September 30, 2025, then gradually stepping down to 4.5x by the fiscal quarter ended December 31, 2026 and thereafter. The amendment also decreased the Revolving Commitments (as defined in the Existing Credit Agreement) from $375 million to $325 million with additional reductions stepping down to $250 million on July 1, 2026.

On September 18, 2024, we received a notice of default relating to our 6.750% Senior Notes due 2027 because we failed to timely furnish a Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2024. We had 90 days from receipt of the notice to remedy prior to it becoming an Event of Default under the terms of the Indenture, dated November 26, 2019. Our Q3 Form 10-Q was filed with the SEC on October 30, 2024.

On ~~December~~September 1213, 2024, we entered into anamendments ~~amendment~~ to our 2023 Credit Agreement, ~~which,~~and ~~among~~our ~~other~~AR ~~things~~Securitization Facility, ~~eased~~which ~~the~~extended ~~restrictions of certain covenants contained in~~ the ~~agreement.~~deadline ~~The~~for ~~amendment~~delivery ~~included increasing the maximum allowed consolidated total net leverage ratio (as defined and calculated under the terms~~ of ~~the~~our ~~amended~~financial ~~2023~~statements ~~Credit~~for ~~Agreement) to 6.5x as of~~ the ~~last day of any~~ quarter ~~through the fiscal quarter~~ ended ~~September~~June 30, ~~2025~~2024, ~~then~~together ~~gradually~~with ~~stepping down to 4.5x by~~ the ~~fiscal~~respective ~~quarter~~compliance ~~ended December 31~~certificates, ~~2026~~to ~~and~~November ~~thereafter.~~29, ~~The~~2024, ~~amendment~~152 ~~also~~days ~~decreased~~after the ~~Revolving~~last ~~Commitments~~day ~~(as~~of ~~defined in~~ the ~~Existing~~quarter ~~Credit~~ended ~~Agreement)~~June ~~from $375 million to $325 million with additional reductions stepping down to $250 million on July 1~~30, ~~2026~~2024.

On ~~May~~August 512, ~~2023~~2024, we entered into anamendments ~~agreement~~ to ~~amend and restate~~ our credit agreement entered into on November 26, 2019 (as in effect prior to such restatement, the “Existing Credit Agreement”) with a new $575 million senior secured credit agreement due May 5, 2028 (as amended, the “2023 Credit Agreement~~”),~~ ~~comprised of a $375 million revolving credit facility~~ and ~~$200 million~~our ~~term~~AR ~~loan.~~Securitization ~~The term loan is payable in quarterly installments of interest and principal~~Facility, which ~~began~~extended ~~September 30, 2023. The 2023 Credit Agreement increases~~ the ~~Applicable~~deadline ~~Margins~~for bydelivery ~~25 basis points over those defined in the Existing Credit Agreement and adds an additional level at a consolidated total leverage ratio (defined below)~~ of ~~greater~~our ~~than~~financial ~~4.00~~statements tofor ~~1.00. Consolidated total net debt includes~~ the ~~aggregate~~quarter ~~principal~~ended ~~amount~~June of30, ~~total debt~~2024, ~~net~~together ofwith ~~unrestricted cash of up to $75 million as per~~ the ~~2023~~respective ~~Credit~~compliance ~~Agreement.~~certificates, ~~Proceeds~~ from ~~the~~45 ~~2023~~days ~~Credit Agreement were used~~ to ~~redeem~~75 ~~our~~days ~~$250 million~~after ~~4.875% Senior Notes on May 10, 2023 and pay off~~ the ~~Existing~~last ~~Credit~~day ~~Agreement term loan balance~~ of ~~$16.9 million.~~the ~~Refer~~quarter toended ~~Item~~June 830, ~~Note 12 of our Consolidated Financial Statements for additional details~~2024.

InOn ~~November~~May ~~2022~~5, 2023, we entered into ~~the~~an ~~third~~agreement ~~amendment~~to amend and restate our credit agreement entered into on November 26, 2019 (as in effect prior to such restatement, the “Existing Credit Agreement”) with a new $575 million senior secured credit agreement due May 5, ~~principally~~2028 to(as ~~affect~~amended, the “2023 Credit Agreement”), comprised of a ~~transition~~$375 million revolving credit facility and $200 million term loan. The term loan is payable in quarterly installments of interest and principal, which began September 30, 2023. The 2023 Credit Agreement increases the Applicable Margins by 25 basis points over those defined in the Existing Credit Agreement and adds an additional level at a consolidated total leverage ratio (defined below) of greater than 4.00 to 1.00. Proceeds from the ~~London~~2023 ~~Inter-Bank~~Credit ~~Offered~~Agreement ~~Rate~~were used to redeem our $250 million 4.875% Senior Notes on May 10, 2023 and pay off the ~~Secured~~Existing ~~Overnight~~Credit ~~Financing~~Agreement ~~Rate~~term ~~pricing~~loan ~~benchmark~~balance ~~provisions~~of $16.9 million. See Item 8, Note 10. Long Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements for additional details.

71On March 27, 2024, ~~FORM~~we ~~10-K~~entered into an amendment to our 2023 Credit Agreement, which eased the restrictions of certain covenants contained in the agreement. The amendment included increasing the maximum allowed consolidated total net leverage ratio (as defined and calculated under the terms of the amended 2023 Credit Agreement) to 6.5x as of the last day of any quarter through the fiscal quarter ended December 31, 2024, then gradually stepping down to 4.75x by the fiscal quarter ended March 31, 2026 and thereafter.


			74			2025 FORM 10-K


Table of Contents						COMPASS MINERALS INTERNATIONAL, INC.

~~Pursuant~~On toJune ~~the~~30, ~~terms~~2020, certain of ~~the~~our ~~amended~~U.S. ~~2023~~subsidiaries ~~Credit~~entered ~~Agreement,~~into ~~the~~a ~~maximum~~three-year ~~allowed~~committed ~~consolidated~~revolving ~~total~~accounts ~~net~~receivable ~~leverage~~financing ~~ratio~~facility ~~(as~~for ~~defined~~up ~~and~~to ~~calculated~~$100.0 million ~~under~~of ~~the~~borrowing ~~terms~~with ofPNC ~~the~~Bank, ~~amended~~National ~~2023~~Association, ~~Credit~~as ~~Agreement~~administrative agent and ~~discussed~~lender, ~~further~~and ~~above)~~PNC isCapital ~~6.5x~~Markets, LLC, as structuring agent. In January 2023, certain of the ~~last~~Company’s ~~day~~U.S. ofsubsidiaries ~~any~~entered ~~quarter~~into ~~through~~the second amendment to the ~~fiscal~~AR ~~quarter~~Securitization ~~ended~~Facility ~~December~~with ~~31,~~PNC ~~2024~~Bank, which ~~steps~~temporarily ~~down~~eased tothe ~~4.75x~~restrictions of certain covenants contained in the ~~quarter~~agreement ~~ending~~through March ~~31,~~2023. ~~2026~~The ~~and~~amendment ~~thereafter.~~made ~~The~~certain ~~consolidated~~adjustments ~~total~~to ~~net~~the ~~leverage~~financial ~~ratio~~tests ~~represents~~including: (i) the default ratio ofand (aii) ~~consolidated~~the ~~total~~delinquency ~~net~~ratio ~~debt~~to make compliance with such tests more likely. On March 27, 2024, certain of our U.S. subsidiaries entered into an amendment to ~~(b)~~its ~~consolidated~~revolving ~~adjusted~~accounts ~~EBITDA~~receivable financing facility with PNC Bank, National Association, extending the facility to March 2027. As of September 30, ~~2024~~2025, ~~our~~we ~~consolidated~~had ~~total~~$45.8 million ~~net~~of ~~leverage~~outstanding ~~ratio~~loans ~~was~~under ~~approximately~~this 4accounts receivable financing facility.~~89x~~ See Item 8, Note 10. Long Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements for more information.

InWe ~~April~~are ~~2022~~in compliance with our debt covenants as of September 30, 2025, although we ~~utilized~~can ~~earnout~~make ~~proceeds~~no ~~from~~assurance ~~the~~that ~~fiscal~~we ~~2021~~will ~~sale~~remain ofin ~~our~~compliance ~~South~~with ~~America~~these ~~specialty~~ratios. ~~plant~~Furthermore, ~~nutrition~~we ~~business~~may ~~and~~need ~~proceeds~~to ~~from~~refinance ~~the~~all ~~sale~~or a portion of our ~~South~~indebtedness ~~America~~on ~~chemicals~~or ~~business~~before tomaturity; ~~repay~~however, ~~approximately~~we ~~$60.6~~cannot ~~million~~provide assurance that we will be able to refinance any of our ~~term~~indebtedness ~~loan~~on ~~balance.~~commercially reasonable terms or at all.

OnWe ~~June~~have ~~30,~~various ~~2020,~~foreign ~~certain~~and ofstate ~~our~~net ~~U.S.~~operating ~~subsidiaries~~loss ~~entered~~(“NOL”) ~~into~~carryforwards athat ~~three-year~~may ~~committed~~be ~~revolving~~used ~~accounts~~to ~~receivable~~offset ~~financing~~a ~~facility~~portion ~~for~~of upfuture totaxable ~~$100.0 million~~income ofto ~~borrowing~~reduce ~~with~~our ~~PNC~~cash ~~Bank,~~income ~~National~~taxes ~~Association,~~that aswould ~~administrative~~otherwise ~~agent~~be ~~and lender~~payable. However, ~~and~~we ~~PNC~~may ~~Capital~~not ~~Markets,~~be ~~LLC,~~able asto ~~structuring~~use ~~agent.~~any Inor ~~January~~all ~~2023,~~of ~~certain~~our ofNOL ~~the~~carryforwards ~~Company’s~~to ~~U.S.~~offset ~~subsidiaries~~future ~~entered~~taxable ~~into~~income ~~the~~and ~~second~~our ~~amendment~~NOL tocarryforwards ~~the~~may ARbecome ~~Securitization~~subject ~~Facility~~to ~~with~~additional ~~PNC~~limitations ~~Bank,~~due ~~which~~to ~~temporarily~~future ~~eased~~ownership ~~the~~changes ~~restrictions~~or otherwise. As of ~~certain~~September 30, ~~covenants~~2025, ~~contained~~we inhad ~~the~~$80.5 ~~agreement~~million ~~through~~of ~~March~~gross ~~2023.~~federal ~~The~~NOL ~~amendment~~carryforwards ~~made~~and ~~certain~~$7.1 ~~adjustments~~million toof ~~the~~net ~~financial~~operating ~~tests~~tax-effected ~~including:~~state ~~(i)~~NOL ~~the~~carryforwards ~~default~~that ~~ratio~~expire ~~and~~beginning ~~(ii)~~in ~~the~~2031. ~~delinquency~~Also ~~ratio~~as toof ~~make~~September 30, ~~compliance~~2025 ~~with~~and ~~such~~September 30, ~~tests~~2024, ~~more~~we ~~likely~~had $1.9 million Onand ~~March~~$2.0 27million, ~~2024~~respectively, ~~certain~~ of ~~our~~tax-effected ~~U.S.~~state ~~subsidiaries~~capital ~~entered~~losses ~~into~~which anwill ~~amendment~~expire tobeginning ~~its~~in ~~revolving~~2027 ~~accounts~~and ~~receivable~~$1.6 million ~~financing~~and ~~facility~~$1.6 ~~with~~million, ~~PNC Bank~~respectively, ~~National~~of ~~Association~~tax-effected federal capital losses, ~~extending~~which ~~the~~will ~~facility~~expire tobeginning ~~March~~in ~~2027~~2025.

AtManagement assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. A significant piece of objective negative evidence evaluated was the cumulative loss incurred in the U.S. over the three-year period ended September 30, ~~2024~~2025. Such objective evidence limits the ability to consider other subjective evidence, wesuch ~~had~~as our projections for future income. On the basis of this evaluation, during the fiscal year ended September 30, 2025, an additional valuation allowance of $3833.91 million has been recorded to recognize only the portion of ~~outstanding~~the ~~loans~~U.S. ~~under~~deferred ~~this~~tax ~~accounts~~assets ~~receivable~~that ~~financing~~are ~~facility~~more likely than not to be realized. ~~See~~The ~~Item~~amount 8of the deferred tax assets considered realizable, ~~Note~~however, 12could be adjusted if estimates of future taxable income during the carryforward period are increased or reduced or if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to ~~our~~subjective ~~Consolidated~~evidence ~~Financial~~such ~~Statements~~as ~~for~~our ~~more~~projections ~~information.~~for income.

We ~~may~~have ~~borrow~~a ~~amounts~~defined ~~under~~benefit ~~the~~pension ~~revolving~~plan ~~credit~~for ~~facility~~certain orof ~~enter~~our ~~into~~current ~~additional~~and ~~financing~~former toUK ~~fund~~employees. ~~our~~Beginning ~~working~~December ~~capital~~1, ~~requirements~~2008, ~~potential~~future ~~acquisitions~~benefits ~~and~~ceased ~~capital~~to ~~expenditures~~accrue ~~and~~ for ~~other~~the ~~general~~remaining ~~corporate~~active ~~purposes.~~employee ~~Although~~participants wein ~~are~~the inplan ~~compliance~~concurrent with ~~our~~the ~~debt~~establishment ~~covenants~~of asa ofdefined ~~September 30,~~contribution ~~2024,~~plan wefor ~~can~~these ~~make~~employees. noGenerally, ~~assurance~~our ~~that~~cash wefunding ~~will~~policy ~~remain~~is into ~~compliance~~make ~~with~~the ~~these~~minimum ~~ratios.~~annual ~~Furthermore,~~contributions werequired ~~may~~by ~~need~~applicable toregulations. As ~~refinance~~of ~~all~~September 30, or2025, athe ~~portion~~fair value of ~~our~~the ~~indebtedness~~plan’s onassets orare ~~before~~in ~~maturity;~~excess ~~however,~~of wethe ~~cannot~~accumulated ~~provide~~benefit ~~assurance~~obligations ~~that~~and we ~~will~~expect to be ~~able~~required to ~~refinance~~use ~~any~~cash offrom operations above our ~~indebtedness~~historical onlevels ~~commercially~~to ~~reasonable~~fund ~~terms~~the orplan atin ~~all~~the future.

Our ability to make scheduled interest and principal payments on our indebtedness, to refinance our indebtedness, to fund planned capital expenditures and to fund acquisitions will depend on our ability to generate cash in the future. This, to a certain extent, is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control. Based on our current level of operations, we believe that cash flow from operations and available cash, together with available borrowings under our revolving credit facility, will be adequate to meet our liquidity needs over the next 12 months.

We have various foreign and state net operating loss (“NOL”) carryforwards that may be used to offset a portion of future taxable income to reduce our cash income taxes that would otherwise be payable. However, we may not be able to use any or all of our NOL carryforwards to offset future taxable income and our NOL carryforwards may become subject to additional limitations due to future ownership changes or otherwise. At September 30, 2024, we had $76.4 million of gross federal NOL carryforwards and $6.1 million of net operating tax-effected state NOL carryforwards that expire beginning in 2031. Also at September 30, 2024 and 2023, we had $2.0 million tax-effected state capital losses that expire beginning in 2027 and $1.6 million of tax-effected federal capital losses that expire beginning in 2025. The NOL carryforwards in Brazil and related valuation allowances were eliminated as of September 30, 2022 given the ending of the Company’s operations in Brazil.

Management assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. A significant piece of objective negative evidence evaluated was the cumulative loss incurred in the U.S. over the three-year period ended September 30, 2024. Such objective evidence limits the ability to consider other subjective evidence, such as our projections for future income. On the basis of this evaluation, for the fiscal year 2024, an additional valuation allowance of $46 million has been recorded to recognize only the portion of the U.S. deferred tax assets that are more likely than not to be realized. The amount of the deferred tax assets considered realizable, however, could be adjusted if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as our projections for income.

We have a defined benefit pension plan for certain of our current and former U.K. employees. Beginning December 1, 2008, future benefits ceased to accrue for the remaining active employee participants in the plan concurrent with the establishment of a defined contribution plan for these employees. Generally, our cash funding policy is to make the minimum annual contributions required by applicable regulations. As of September 30, 2024, the fair value of the plan’s assets are in excess of the accumulated benefit obligations and we expect to be required to use cash from operations above our historical levels to fund the plan in the future.

Dispositions

On April 20, 2022, we completed the sale of our South America chemicals business to a subsidiary of Cape Acquisitions LLC. Upon closing of the all-cash sale, we received gross proceeds of approximately $51.5 million based on exchange rates at the time of receipt, including a post-closing adjustment and compensation for $6.4 million cash on hand that transferred to the buyer. The sale included all of our remaining operations in Brazil, concluding the previously announced plan to exit the South

72 2024 FORM 10-K

Table of Contents COMPASS MINERALS INTERNATIONAL, INC.

American market. We recorded losses on the sales of the South American specialty plant nutrition business, the investment in Fermavi and the South America chemicals business totaling approximately $323.1 million. These losses were partially offset by approximately $30.6 million of gain from the sale of a component of the North America micronutrient business.

Off-Balance Sheet Arrangements

At September 30, 2024, we had no off-balance sheet arrangements that have or are likely to have a material current or future effect on our consolidated financial statements.

Contractual Obligations

We believe we have sufficient liquidity to fund our operations and meet both short-term and long-term obligations. Our material future obligations include the contractual obligations and other commitments as described below.

We are party to contractual obligations involving commitments to make payments to third parties. These obligations impact our liquidity and capital resource needs. As of September 30, ~~2024~~2025, we had total future contractual obligations of approximately $1.43 billion, with approximately $~~141~~127.65 million due during fiscal ~~2025~~2026.

We have a contractual commitment to repay our long-term debt of $~~922~~845.8 million based on the terms of our debt agreements, of which $70.50 million is payable within the next twelve months. Our interest commitment based on the debt balances at September 30, ~~2024~~2025 is $~~215~~282.85 million, with $64.93 million expected within the next twelve months. The remainder of our contractual commitments consist of lease payments, purchase obligations and commitments, income taxes and employer pension and benefit plan obligations.

~~See~~75 ~~Item~~2025 8,FORM Note 6 and Item 8, Note 12 to our Consolidated Financial Statements for amounts outstanding as of September 30, 2024 related to leases and debt, respectively. Our contractual obligations related to income taxes represent the one-time transition tax obligation. Refer to Item 8, Note 13 for amounts related to purchase obligations and performance bonds. See Item 8, Note 10 for information related to income taxes. Our contractual obligations related to employer pension plan obligations represent the funded status recognized as of September 30, 2024. See Item 8, Note 11 for information related to these plans.-K

InTable ~~addition, we have other future contingent commitments~~ of ~~approximately~~Contents ~~$250.1~~COMPASS ~~million,~~MINERALS ~~consisting of letters of credit and performance bonds~~INTERNATIONAL, ~~due during fiscal 2025~~INC. At September 30, 2024, we had $242.4 million of outstanding performance bonds, which includes bonds related to Ontario mining tax reassessments. Refer to Item 8, Note 13 for additional details. We also have contingent consideration liabilities related to the Fortress acquisition currently valued at $7.9 million as of September 30, 2024. The milestone portion of the contingency is to be paid upon the achievement of certain performance measures over the next five years (currently estimated to be $4.7 million in total), and a cash earn-out based on financial performance and volumes of certain Fortress fire retardant products sold over a 10-year period (currently estimated to be $3.2 million in total). Refer to Item 8, Note 3 and Item 8, Note 17 for additional information.

See Item 8, Note 4. Leases and Note 10. Long Term Debt and Finance Lease Liabilities of our Consolidated Financial Statements for amounts outstanding as of September 30, 2025 related to leases and debt, respectively. Refer to Item 8, Note 11. Commitments and Contingencies and Note 18. Subsequent Event of our Consolidated Financial Statements for amounts related to purchase obligations and performance bonds. Our contractual obligations related to employer pension plan obligations represent the funded status recognized as of September 30, 2025. See Item 8, Note 9. Pension Plans and Other Benefits of our Consolidated Financial Statements for information related to these plans.

In addition, we have other future contingent commitments of approximately $231.6 million, consisting of letters of credit and performance bonds, due during fiscal 2026. At September 30, 2025, we had $211.5 million of outstanding performance bonds, which includes bonds related to Ontario mining tax reassessments, and with the settlement that occurred during the first quarter of fiscal 2026, the bonds posted as collateral for the 2002-2018 period were released. Refer to Item 8, Note 11. Commitments and Contingencies and Note 18. Subsequent Event of our Consolidated Financial Statements for additional details.

Product Recall

On October 25, 2024, we issued a recall for ~~nine~~specific production lots of food-grade salt produced at our Goderich Plant following a customer report of a non-organic, foreign material in our product. ~~The~~We ~~products~~subsequently ~~recalled~~expanded ~~included~~the ~~both~~voluntary recall to include food products ~~sold~~from ~~prior~~the ~~and~~Goderich ~~subsequent~~Plant tobetween September 3018, 2024 and November 6, 2024. We followed recall protocol and notified ~~our~~the BRCGS Global Standard for Food Safety certifying body, the Canadian Food Inspection Agency (“CFIA”) and the U.S. Food and Drug Administration (“FDA”). We ~~have~~completed ~~been~~our ~~working~~investigation toand ~~obtain~~continue ~~and~~to assess the ~~reported~~scope ~~foreign~~and ~~material,~~magnitude ~~complete~~of ~~the~~customer ~~necessary~~claims ~~investigation,~~related ~~and~~to ~~determine~~ the ~~next steps~~recall. ~~Based~~At this time, based on ~~initial~~currently ~~feedback~~available ~~received~~information ~~from~~and ~~customers~~our ~~impacted~~applicable byinsurance ~~the~~coverage, ~~recall~~we ~~and~~do ~~other~~not ~~currently~~believe ~~available~~any ~~information,~~incremental welosses will have ~~recorded~~a ~~$0.8~~material ~~million~~adverse ~~for~~effect ~~estimated~~on ~~costs~~our ~~expected~~results toof beoperations ~~borne~~or bycash ~~us,~~flows ~~which~~in wefuture ~~have~~periods. ~~included~~The recall in ~~other~~the ~~(income)~~United ~~expense~~States, onsupervised by the ~~Consolidated~~FDA, ~~Statements~~is ofcomplete, ~~Operations~~and ~~for~~ the ~~year~~matter ~~ended~~is ~~September~~closed ~~30,~~with ~~2024~~FDA. ~~Additionally,~~The asCFIA ofhas ~~September~~conducted ~~30,~~a ~~2024,~~follow-up weinspection ~~have~~of ~~recorded~~the ~~additional~~Goderich ~~reserves~~Plan ofto ~~$6.7~~verify ~~million~~compliance with regulatory requirements and ~~estimated~~identified ~~insurance~~no ~~recoveries~~non-compliances. ofSee $6Item 8, Note 11.~~7 million~~ inCommitments and Contingencies of our Consolidated ~~Balance~~Financial ~~Sheets~~Statements for additional information.

WeOff-Balance ~~continue~~Sheet to assess the scope and magnitude of additional customer claims for product produced and shipped after September 30, 2024. At this time, based on currently available information and our applicable insurance coverage, we do not believe any incremental losses will have a material adverse effect on our results of operations or cash flows in future periods.Arrangements

~~Reconciliation~~At ofSeptember 30, ~~Net~~2025, ~~(Loss)~~we ~~Earnings~~had ~~from~~no ~~Continuing~~off-balance ~~Operations~~sheet arrangements that have or are likely to ~~EBITDA~~have ~~and~~a ~~Adjusted~~material ~~EBITDA~~current or future effect on our consolidated financial statements.

~~Management~~Liquidity uses a variety of measures to evaluate our performance. While our consolidated financial statements, taken as a whole, provide an understanding of our overall results of operations, financial condition and ~~cash~~Capital ~~flows,~~Resources—For ~~we analyze components of~~ the ~~consolidated~~Fiscal ~~financial~~Year ~~statements~~Ended toSeptember ~~identify certain trends and evaluate specific performance areas. In addition to using U.S. GAAP financial measures~~30, ~~such as gross profit~~2024, ~~net~~Compared earnings and cash flows generated by operating activities, management uses EBITDA and Adjusted EBITDA. We have presented Adjusted EBITDA for both continuing operations and consolidated including discontinued operations for comparative purposes (see Item 8, Note 4 to ~~our Consolidated Financial Statements for a discussion of discontinued operations). Both EBITDA and Adjusted EBITDA are non-U.S. GAAP financial measures used to evaluate~~ the ~~operating~~Fiscal ~~performance~~Year ofEnded ~~our~~September ~~core~~30, ~~business operations because our resource~~ 2023

73For a comparison of our liquidity and capital resources for the fiscal year ended September 30, 2024, ~~FORM~~compared to the fiscal year ended September 30, 2023, see “Part II, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” of our Form 10-K for the fiscal year ended September 30, 2024, filed with the SEC on December 16, 2024, which is incorporated herein by reference.

Reconciliation of Net Loss to EBITDA and Adjusted EBITDA

Management uses a variety of measures to evaluate our performance. While our consolidated financial statements, taken as a whole, provide an understanding of our overall results of operations, financial condition and cash flows, we analyze components of the consolidated financial statements to identify certain trends and evaluate specific performance areas. In addition to using U.S. GAAP financial measures, such as gross profit, net (loss) income and cash flows generated by operating activities, management uses earnings before interest, taxes, depreciation and amortization (“EBITDA”) adjusted for items management believes are not indicative of our ongoing operating performance (“Adjusted EBITDA”). Both EBITDA and Adjusted EBITDA are non-U.S. GAAP financial measures used to evaluate the operating performance of our core business operations because our resource allocation, financing methods and cost of capital, and income tax positions are managed at a corporate level, apart from the activities of the operating segments, and our operating facilities are located in different taxing jurisdictions, which can cause considerable variation in net earnings. We also use EBITDA and Adjusted EBITDA to assess our operating performance and return on capital against other companies, and to evaluate potential acquisitions or other capital projects. EBITDA and Adjusted EBITDA are not calculated under U.S. GAAP and should not be considered in isolation or as a substitute for net income, cash flows or other financial data prepared in accordance with U.S. GAAP or as a measure of our overall profitability or liquidity.


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Table of Contents						COMPASS MINERALS INTERNATIONAL, INC.

~~allocation~~EBITDA and Adjusted EBITDA exclude interest expense, ~~financing~~income ~~methods~~taxes and ~~cost~~depreciation and amortization, each of ~~capital~~which are an essential element of our cost structure and cannot be eliminated. Furthermore, Adjusted EBITDA excludes other cash and non-cash items, including stock-based compensation, interest income, ~~tax~~(gain) ~~positions~~loss ~~are~~on ~~managed~~foreign atexchange, aother ~~corporate~~(income) ~~level~~expense, ~~apart~~net ~~from~~and ~~the~~other ~~activities~~significant items that management does not consider indicative of ~~the~~normal ~~operating~~operations. Other ~~segments~~significant items, such as executive transition costs, restructuring charges and ~~the~~impairment charges, involve distinct initiatives that are not reflective of core operating ~~facilities~~activities and affect the comparability of our operational results across reporting periods. Our borrowings are ~~located~~a insignificant ~~different~~component ~~taxing~~of ~~jurisdictions,~~our ~~which~~capital ~~can~~structure ~~cause~~and ~~considerable~~interest ~~variation~~expense inis ~~net~~a ~~earnings~~continuing cost of debt. We are also ~~use~~required ~~EBITDA~~to ~~and~~pay ~~Adjusted~~income ~~EBITDA~~taxes, toa ~~assess~~required and ongoing consequence of our ~~operating~~operations. We ~~performance~~have ~~and~~a ~~return~~significant oninvestment in capital ~~against~~assets ~~other~~and ~~companies,~~depreciation and toamortization ~~evaluate~~reflect ~~potential~~the ~~acquisitions~~utilization orof ~~other~~those ~~capital~~assets ~~projects~~in order to generate revenues. Our ~~EBITDA~~employees are vital to our operations and ~~Adjusted~~we ~~EBITDA~~utilize ~~are~~various ~~not~~stock-based ~~calculated~~awards ~~under~~to Ucompensate and incentivize our employees.S. ~~GAAP~~Consequently, ~~and~~any ~~should~~measure ~~not~~that beexcludes ~~considered~~these inelements ~~isolation~~has ormaterial aslimitations. While aEBITDA ~~substitute~~and ~~for~~Adjusted ~~net~~EBITDA ~~earnings,~~are ~~cash~~frequently ~~flows~~used oras ~~other~~measures ~~financial~~of ~~data~~operating ~~prepared~~performance, inthese ~~accordance~~terms ~~with~~are ~~U.S.~~not ~~GAAP~~necessarily orcomparable asto asimilarly ~~measure~~titled measures of ~~our~~other ~~overall~~companies ~~profitability~~due orto ~~liquidity.~~the potential inconsistencies in the method of calculation.

~~EBITDA and~~ Adjusted EBITDA ~~exclude~~decreased ~~interest expense~~3.6%, ~~income~~or ~~taxes and depreciation, depletion and amortization, each of which are an essential element of our cost structure and cannot be eliminated~~$7. ~~Furthermore,~~5 ~~Adjusted~~million ~~EBITDA~~for ~~excludes~~the ~~other~~fiscal ~~cash~~year ~~and~~ended ~~non-cash~~September ~~items~~30, ~~including stock-based compensation~~2025, ~~interest~~compared ~~income,~~to ~~(gain)~~the ~~loss~~fiscal onyear ~~foreign~~ended ~~exchange,~~September ~~other (income) expense~~30, ~~net and other significant items that management does not consider indicative of normal operations. Other significant items~~2024, ~~such~~primarily asdue ~~executive~~to ~~transition~~a ~~costs,~~reduction ~~restructuring~~in ~~charges and impairment charges and~~ gain ~~from~~related ~~remeasurement~~to ofthe ~~equity~~Fortress ~~method~~contingent ~~investment,~~consideration ~~involve distinct initiatives that are not reflective~~ of ~~core operating activities and affect the comparability of our operational results across reporting periods~~$14.2 ~~Our~~million ~~borrowings are a significant component of our capital structure~~ and ~~interest expense is~~ a ~~continuing~~reduction ~~cost~~in ofgross ~~debt. We are also required to pay income taxes~~profit, apartially ~~required~~offset ~~and~~by ~~ongoing consequence of our operations. We have~~ a ~~significant~~decrease ~~investment~~ in ~~capital~~selling, ~~assets~~general and ~~depreciation~~administrative ~~and~~expenses. ~~amortization~~The ~~reflect~~calculation ~~the utilization~~ of those assets in order to generate revenues. Our employees are vital to our operations and we utilize various stock-based awards to compensate and incentivize our employees. Consequently, any measure that excludes these elements has material limitations. While EBITDA and Adjusted EBITDA ~~are~~as ~~frequently~~ used asby ~~measures~~management ofis ~~operating~~set ~~performance,~~forth ~~these~~in ~~terms are not necessarily comparable to similarly titled measures of other companies due to~~ the ~~potential~~table ~~inconsistencies~~below (in ~~the~~millions): ~~method of calculation.~~

The calculation of EBITDA and Adjusted EBITDA as used by management is set forth in the table below (in millions).


	Fiscal Year Ended
	September 30, 2025		September 30, 2024

Net loss	$	(79.8)	$	(206.1)
Interest expense	68.5		69.5
Income tax expense	26.1		17.9
Depreciation, depletion and amortization	103.2		105.0
EBITDA	118.0		(13.7)
Adjustments to EBITDA:
Stock-based compensation - non-cash	10.2		8.1
Interest income	(1.3)		(1.0)
(Gain) loss on foreign exchange	(0.1)		0.7
Loss on extinguishment of debt	7.6		—


Restructuring charges(a)	4.3		15.8
Total impairment loss(b)	53.7		193.4
Product recall costs(c)	2.1		0.8

Other expense, net	4.3		2.2
Adjusted EBITDA	$	198.8	$	206.3

	Fiscal Year Ended
	September 30,2024		September 30,2023		September 30,2022
Net (loss) earnings from continuing operations	$	(206.1)	$	10.5	$	(33.3)
Interest expense	69.5		55.5		55.2
Income tax expense	17.9		17.1		33.5
Depreciation, depletion and amortization	105.0		98.6		112.8
EBITDA from continuing operations	(13.7)		181.7		168.2
Adjustments to EBITDA from continuing operations:
Stock-based compensation - non-cash	8.1		20.6		15.7
Interest income	(1.0)		(5.3)		(0.8)
Loss (gain) on foreign exchange	0.7		2.3		(14.9)
Gain from remeasurement of equity method investment	—		(10.1)		—
Restructuring charges(a)	15.8		5.9		4.3
Loss on impairments(b)	193.4		—		—
Provision for product recall costs(c)	0.8		—		—
Accrued loss and legal costs related to SEC investigation(d)	—		(0.3)		17.1
Other expense, net	2.2		4.3		0.5
Adjusted EBITDA from continuing operations	206.3		199.1		190.1
Adjusted EBITDA from discontinued operations	—		—		19.0
Adjusted EBITDA including discontinued operations	$	206.3	$	199.1	$	209.1

(a)During the fiscal year ended September 30, 2025, we incurred severance and related charges due to a reduction in workforce. During the fiscal year ended September 30, 2024, we incurred severance and related charges related to reductions in workforce, changes to executive leadership and additional restructuring costs related to the termination of our lithium development project.

(ab)WeDuring ~~incurred~~the ~~severance~~fiscal ~~and~~year ~~related~~ended ~~charges~~September 30, 2025, we recorded a loss on impairment of $53.0 million, related to ~~reductions~~Fortress inintangible ~~workforce~~assets and $0.7 million, ~~changes~~related to ~~executive~~Fortress ~~leadership~~long-lived ~~and~~assets. ~~additional~~During ~~restructuring~~the ~~costs~~fiscal year ended September 30, 2024, we recorded a loss on impairment of long-lived assets of $74.8 million related to the termination of ~~our~~the lithium development project; goodwill of $32.0 million related to Fortress, long-lived assets of $15.6 million and inventory of $2.4 million related to Fortress; and goodwill of $51.0 million related to Plant Nutrition for the twelve months ended Sept. 30, 2024. Impairments of long-lived assets, intangible assets, and goodwill are included in loss on impairments, while the impairment of inventory is included in product cost, both on the Consolidated Statements of Operations. Refer to Item 8, Note 2. Summary of Significant Accounting Policies and Note 15. Fair Value Measurements of our Consolidated Financial Statements for additional details.

(bc)We ~~recognized~~recorded ~~impairments~~product ofrecall ~~long-lived~~costs ~~assets~~ related to ~~the~~a ~~termination~~recall offor ~~the~~food-grade ~~lithium~~salt ~~development~~produced ~~project;~~at ~~Fortress~~our ~~goodwill,~~Goderich ~~intangible assets and inventory; and~~ Plant ~~Nutrition goodwill and water rights~~. Refer to Item 8, Note 2,11. ~~Item~~Commitments 8,and ~~Note~~Contingencies 8of ~~and~~our ~~Item~~Consolidated 8,Financial ~~Note~~Statements 9 for additional details.

~~(c)We~~Our ~~recorded~~net aincome, ~~provision~~EBITDA ~~for~~and ~~potential~~Adjusted ~~costs~~EBITDA ~~related~~are toimpacted aby ~~recall~~other ~~for~~events ~~food-grade~~or ~~salt~~transactions ~~produced~~that atwe believe to be important in understanding our ~~Goderich~~earnings ~~Plant~~trends such as the variability of weather. ~~Refer~~The impact of weather has not been adjusted in the amounts presented above. Our fiscal year ended September 30, 2025 results included a more normal winter weather in the North American deicing season, which led to ~~Item~~a 820% increase in highway deicing sales volume. Our fiscal year ended September 30, ~~Note~~2024 13results ~~for~~were ~~additional~~unfavorably ~~details~~impacted by winter weather activity as compared to an average winter in the markets we serve.

~~(d)We~~77 ~~recognized~~2025 ~~costs,~~FORM ~~net of reimbursements, related to the settled SEC investigation during the fiscal year ended September 30, 2023, and recorded a settlement loss accrual during the fiscal year ended September 30, 2022.~~10-K

Adjusted EBITDA also excludes other non-operating income, primarily non-cash stock-based compensation expense, foreign exchange gains (losses) resulting from the translation of intercompany obligations, interest income and investment income (loss) relating to our nonqualified retirement plan.

74 2024 FORM 10-K


Table of Contents						COMPASS MINERALS INTERNATIONAL, INC.

~~Our~~Management’s ~~net~~Discussion ~~earnings, EBITDA and Adjusted EBITDA are impacted by other events or transactions that we believe to be important in understanding our earnings trends such as the variability~~ of ~~weather.~~Critical ~~The~~Accounting impact of weather has not been adjusted in the amounts presented above. Our fiscal 2024, 2023 and 2022 results were unfavorably impacted by winter weather activity as compared to an average winter in the markets we serve. Estimates

~~Management’s~~The ~~Discussion~~preparation of ~~Critical~~the ~~Accounting~~consolidated ~~Policies~~financial statements in conformity with U.S. GAAP requires management to make estimates and ~~Estimates~~assumptions that affect the reported amounts of assets and liabilities as of the reporting date and the reported amounts of revenue and expenses during the reporting period. Actual results could vary from these estimates. We have identified the critical accounting estimates that we believe are most important to the portrayal of our financial condition and results of operations. The estimates set forth below require significant subjective or complex judgments by management, often as a result of the need to make estimates about the effect of matters that are inherently uncertain.

~~The~~Intangible ~~preparation~~Assets. ofOn ~~the~~March ~~consolidated~~25, ~~financial~~2025, ~~statements~~we intook ~~conformity~~measures ~~with~~to ~~U.S.~~align ~~GAAP~~our ~~requires~~cost ~~management~~structure to ~~make~~our ~~estimates~~current ~~and~~business ~~assumptions~~needs ~~that~~as ~~affect~~part ~~the reported amounts~~ of ~~assets~~a ~~and~~larger ~~liabilities~~strategic asrefocus ofto ~~the~~improve ~~reporting date and~~ the ~~reported~~profitability ~~amounts~~ of ~~revenue~~our ~~and~~core ~~expenses~~Salt ~~during the reporting period. Actual results could vary from these estimates. We have identified the critical accounting policies~~ and ~~estimates~~Plant ~~that~~Nutrition webusinesses, ~~believe~~including ~~are most important to~~ the ~~portrayal~~process of ~~our~~exiting ~~financial~~the ~~condition~~Fortress ~~and~~North ~~results of operations. The policies set forth below require significant subjective or complex judgments by management~~America, ~~often~~LLC as(“Fortress”) afire ~~result~~retardant ofbusiness ~~the~~and ~~need~~terminating ~~to make estimates about~~ the ~~effect~~employment of ~~matters~~all ~~that~~Fortress ~~are inherently uncertain~~employees.

~~Intangible~~As ~~Assets~~a -result ~~Finite-lived~~of ~~intangible~~the ~~assets~~above ~~are~~items ~~amortized~~impacting ~~over their respective estimated useful lives. Intangible assets with indefinite lives are not amortized~~Fortress, ~~but~~we ~~rather~~determined ~~are tested for impairment at least annually or more frequently if events occur or circumstances change~~ that ~~would~~there ~~more~~were ~~likely~~indicators ~~than~~of ~~not~~impairment ~~reduce~~with the ~~fair~~associated ~~value~~Fortress ~~of the~~ intangible ~~asset below its carrying amount~~assets. ~~Our finite-lived intangible assets include customer relationships~~Therefore, ~~developed~~we ~~technology,~~tested ~~trade~~these ~~name,~~intangibles ~~supply~~for ~~agreements, SOP production rights and lease rights~~impairment. ~~Our~~As ~~indefinite-lived~~there ~~intangible~~were ~~assets~~no ~~include~~future ~~trade~~cash ~~names~~flows ~~and~~expected ~~in-process~~related ~~research and development. We may first assess qualitative factors~~ to ~~determine~~these ~~whether~~intangible ~~it is necessary to perform a quantitative impairment test. A qualitative assessment (“Step 0 test”) may include~~assets, ~~but~~customer isrelationships ~~not~~was ~~limited~~determined to, ~~reviewing~~have ~~factors such as macroeconomic conditions, industry and market considerations, cost factors, financial performance and other entity or reporting unit specific events. When performing~~ a ~~Step 0 test, if we determine that it is more likely than not that the~~ fair value of azero ~~reporting~~using ~~unit~~an isincome ~~less~~approach ~~than~~under ~~its~~ASC ~~carrying value~~820, weFair ~~then~~Value ~~perform~~Measurement ~~a quantitative goodwill impairment analysis~~ (~~“Step~~Level 13 ~~test”~~inputs). byConsequently, ~~comparing~~we ~~the~~recorded ~~carrying~~a ~~amount~~loss toon animpairment ~~estimate~~ of ~~the fair value of the reporting unit~~$53.0 Ifmillion, ~~the~~for ~~fair value of~~ the ~~indefinite-lived~~fiscal ~~intangible~~year ~~asset~~ended isSeptember ~~less than the carrying amount~~30, ~~an impairment loss is recognized in an amount equal to the difference~~2025.

~~The~~Additionally, ~~unit~~we ofperformed ~~accounting~~an ~~used~~impairment to test ~~our~~on ~~indefinite-lived intangible assets for impairment is at~~ the ~~reporting~~remaining ~~unit~~Fortress ~~level.~~asset ~~The~~group ~~fair~~(including ~~values~~property, ofplant ~~our~~and ~~indefinite-lived~~equipment ~~trade~~(“PP&E”), ~~names~~inventory and in-process research and development ~~are~~(“IPR&D”), ~~determined~~with ~~for~~a carrying amount of $19.7 million. The impairment ~~testing~~test ~~purposes~~under ~~based~~ASC on360, anProperty, ~~income~~Plant ~~approach.~~Equipment ~~Under~~and Other Assets, compared the ~~income~~asset ~~approach,~~group’s weundiscounted ~~are~~cash ~~required~~flows to ~~make~~its ~~judgments~~carrying ~~about~~amount. ~~appropriate~~We ~~discount~~determined ~~rates,~~the ~~long-term~~fair ~~revenue~~value ~~growth~~of ~~rates~~the ~~and~~asset ~~the~~group ~~amount~~using ~~and~~a ~~timing~~market ofapproach ~~expected~~under ~~future~~ASC ~~cash~~820, ~~flows~~Fair Value Measurement. The ~~cash~~fair ~~flows~~value ~~used~~of inthe ~~its~~asset ~~estimates~~group ~~are~~was based on relevant third-party non-binding offers received for the ~~reporting~~specific ~~unit's~~asset ~~forecast,~~group ~~long-term~~(Level ~~business~~2 ~~plan~~inputs). The asset group (PP&E, inventory and ~~recent~~IPR&D) ~~operating~~was ~~performance.~~not ~~Discount~~impaired ~~rate~~as ~~assumptions~~its ~~are~~fair value, based on anmarket ~~assessment~~indications, ofapproximated ~~the~~or ~~risk~~exceeded ~~inherent~~its incarrying value. The fair value estimates involved significant estimates and assumptions, which may differ from actual outcomes. At June 30, 2025, the ~~future~~Company ~~cash~~performed ~~flows~~an ofimpairment test on the ~~respective~~remaining ~~reporting~~Fortress ~~unit~~asset group related to PP&E and ~~market~~recorded ~~conditions~~a loss on impairment of $0.7 ~~Our~~million, ~~estimates~~during ~~may~~the ~~differ~~fiscal ~~from~~year ~~actual~~ended ~~future~~September ~~cash~~30, ~~flows~~2025.

~~For~~Mineral ~~finite-lived~~Interests ~~intangible~~– ~~assets,~~As weof ~~amortize~~September 30, ~~over~~2025 ~~periods~~and ~~that~~September ~~range~~30, ~~from~~2024, ~~five~~we tomaintained ~~fifty~~$115.8 ~~years;~~million ~~refer~~and to$117.7 ~~Item~~million, 8respectively, ~~Note~~of 9net ~~for~~mineral ~~additional~~properties ~~details.~~as Wea ~~perform~~part anof ~~impairment~~property, ~~review~~plant ofand ~~finite-lived~~equipment. Mineral ~~intangible~~interests ~~assets~~include ~~when~~probable ~~facts~~mineral ~~and~~reserves. ~~circumstances~~We ~~indicate~~lease ~~that~~mineral ~~the~~reserves ~~carrying~~at ~~value~~several of anour ~~asset~~extraction ~~may~~facilities. ~~not~~These beleases ~~recoverable~~have ~~from~~varying ~~its~~terms, ~~undiscounted~~and ~~future~~many ~~cash~~provide ~~flows.~~for ~~The~~a ~~impairment~~royalty ~~test~~payment ~~for~~to ~~finite-lived~~

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