v2.4.0.6

Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Cash and cash equivalents	$ 75,093	$ 79,817
Receivables	4,964	2,015
Receivable from Arch Coal, Inc.	473,803	582,384
Inventories	170,439	150,419
Other	22,162	21,435
Total current assets	746,461	836,070
Property, plant and equipment
Coal lands and mineral rights	763,059	763,059
Plant and equipment	1,798,404	1,665,285
Deferred mine development	577,332	548,776
Property, plant and equipment, gross, total	3,138,795	2,977,120
Less accumulated depreciation, depletion and amortization	(1,624,296)	(1,488,277)
Property, plant and equipment, net	1,514,499	1,488,843
Other assets:
Receivable from Arch Coal, Inc.	1,234,918	910,797
Other	12,955	10,920
Total other assets	1,247,873	921,717
Total assets	3,508,833	3,246,630
LIABILITIES AND MEMBERSHIP INTERESTS
Accounts payable	183,151	121,670
Accrued expenses and other current liabilities	166,762	153,141
Commercial paper		56,904
Total current liabilities	349,913	331,715
Long-term debt	450,971	451,618
Note payable to Arch Coal, Inc.	225,000	225,000
Asset retirement obligations	305,046	301,355
Accrued postretirement benefits other than pension	22,195	23,509
Accrued pension benefits	24,843	23,904
Other noncurrent liabilities	44,104	43,015
Total liabilities	1,422,072	1,400,116
Redeemable membership interest	11,534	10,444
Total liabilities and membership interests	3,508,833	3,246,630
Non-Redeemable Membership Interest [Member]
LIABILITIES AND MEMBERSHIP INTERESTS
Non-redeemable membership interest	$ 2,075,227	$ 1,836,070

Carrying value as of the balance sheet obligations incurred and payable, pertaining to costs that are statuary in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered, and of current obligations not separately disclosed in the balance sheet due to materiality considerations, which are expected to be paid within one year.

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The gross amount of mineral rights, or rights to extract a mineral from the earth or to receive payment in the form of a royalty for the extraction of minerals, and land held for production use.

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Costs of developing new mines or significantly expanding the capacity of existing mines. Costs may include: construction permits and licenses; mine design; construction of access roads, shafts, slopes and main entries; and removing overburden to access reserves in a new pit.

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The amount of ownership interest of different classes of partners in limited partnership.

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