CLEAN HARBORS INC 8-K

What Happened Clean Harbors Inc. (CLH) filed an 8-K reporting that Alan S. McKim, who serves as Executive Chairman of the Board and Chief Technology Officer, notified the Board on May 19, 2026 of his intention to retire from the Board and his CTO role. The company issued a press release on May 20, 2026 (Exhibit 99.1) announcing the planned retirement, which will take effect upon the Board’s appointment of a new independent Chairman.

Key Details

• Notice date: May 19, 2026; press release dated May 20, 2026 (furnished as Exhibit 99.1).
• Roles affected: Executive Chairman of the Board and Chief Technology Officer (Alan S. McKim).
• Effective timing: Retirement effective upon appointment of a new independent Chairman, anticipated in summer 2026, as part of a planned leadership transition.
• Company statement: Mr. McKim’s decision is not due to any disagreement with the company regarding operations, policies, practices, or similar matters.

Why It Matters This filing documents a planned senior leadership change at Clean Harbors (Board chair and technology leadership). The company expects an independent Chairman to be named in the summer of 2026, marking a leadership transition that investors may monitor for any subsequent governance or management updates. The filing explicitly states the departure is not the result of disagreement, which is a material disclosure for governance and continuity considerations.