On July 17, 2014, EPA proposed to update its New Source Performance Standards (NSPS) for municipal solid waste (MSW) landfills for the first time since 1996. The proposed NSPS would require reductions in emissions of methane and other landfill gases at MSW landfills that commenced construction, reconstruction, or modification on or after July 17, 2014. EPA simultaneously issued an Advanced Notice of Proposed Rulemaking (ANPR), requesting public input on methods to reduce emissions of methane, carbon dioxide, and other landfill gases from existing MSW landfills. EPA intends to use the information obtained in response to the ANPR in its review of the emissions guidelines for existing MSW landfills, which were issued in 1996. Both proposals are part of President Obama’s Climate Action Plan to reduce emissions of greenhouse gases.