The Environmental Protection Agency (EPA) received four petitions for reconsideration, rulemaking, or reopening of the Endangerment and Cause or Contribute Findings for Greenhouse Gases under Section 202(a) of the Clean Air Act (CAA), published in the Federal Register on December 15, 2009. The agency is providing notification of its action denying all four petitions. The basis for EPA's action is set out fully in the accompanying decision document, available in the docket for this action.