	Introduction

On March 28, 2017, President Trump issued Executive Order 13783, which aims to promote the development or use of domestically produced energy resources. The order specifically requires the U.S. Environmental Protection Agency (EPA) to review the revised volatile organic compounds (VOCs) and GHG (namely methane) emission standards for new, modified, and reconstructed equipment, processes, and activities of the oil and natural gas sector issued by the Obama Administration in June 2016. EPA issued these emission standards pursuant to Section 111 of the Clean Air Act (CAA) and the Methane Strategy. Although the methane emission standards and guidelines for new and existing municipal solid waste (MSW) landfills are not specifically mentioned in Executive Order 13783, EPA has also reviewed and is currently reconsidering several requirements of the MSW landfill emission standards and guidelines that the Obama Administration updated in August 2016. EPA's review of the oil and natural gas sector and landfill methane rules has influenced several judicial challenges to the Obama-era rules. The U.S. Court of Appeals for the District of Columbia Circuit (D.C. Circuit) granted EPA's requests to pause the judicial challenges to allow EPA to complete its review of the regulations. In addition, EPA has attempted to stay the requirements that are being reconsidered by the agency, but courts have restricted the agency's ability to stay such requirements. This report examines the statutory authority for issuing the various methane regulations, legal challenges to the standards, and legal issues related to the reconsideration and stay of these regulations. Judicial review of EPA's attempts to stay rules already in effect could have broader effects on the Trump Administration's efforts to similarly stay or postpone requirements in other rules that are under reconsideration. Petitions for Judicial Review

Although EPA is reconsidering the 2016 Oil and Gas NSPSs, the underlying rule is also being challenged in court. The agency also revised the 1996 emission guidelines for existing landfills operating prior to that date. The updated NSPSs aimed to further decrease methane emissions from MSW landfills. Both rules became effective on October 28, 2016 and remain in effect unless EPA finalizes a stay or revises the rules. At this time, EPA has not formally proposed a longer stay of the rules or initiated the public comment period for issues under reconsideration.
On March 28, 2017, President Trump signed Executive Order 13783, directing federal agencies to review existing regulations and policies that potentially burden the development or use of domestically produced energy resources. Acting pursuant to the order, the U.S. Environmental Protection Agency (EPA) is reviewing and reconsidering several regulations issued during the Obama Administration that address methane emissions from various industrial sectors. Methane is a short-lived greenhouse gas (GHG) with a Global Warming Potential of more than 25 times carbon dioxide that is emitted from various industrial activities.
President Trump's executive order specifically requires EPA to review the revised emission standards for new, modified, and reconstructed equipment, processes, and activities of the oil and natural gas sector issued by the Obama Administration in June 2016. EPA issued these standards for methane and volatile organic compound (VOC) emissions pursuant to Section 111 of the Clean Air Act (CAA). Based on its review and in response to several administrative petitions for reconsideration, EPA is now reconsidering certain emission requirements from the June 2016 rule, which remain in effect unless EPA finalizes a proposed two-year stay of these requirements or otherwise repeals those requirements.
In addition, EPA is reconsidering the emission standards and guidelines for new and existing municipal solid waste (MSW) landfills updated by the Obama Administration in August 2016. In those rules, EPA issued the updated and revised emission standards for MSW landfills built after 2014 to further reduce emissions, including methane emissions. The agency also revised emission guidelines established in 1996 for existing landfills operating prior to that date. At this time, the 2016 landfill rules are in effect. EPA has not formally proposed any revisions to the 2016 rules or initiated a public comment period for any issues under reconsideration.
EPA's review of the oil and natural gas sector and landfill methane rules has influenced the pending judicial challenges to the various 2016 rules. The U.S. Court of Appeals for the District of Columbia Circuit granted EPA's requests to pause the judicial challenges of both rules to allow EPA to complete its review of them. In addition, stakeholders have successfully challenged in court EPA's attempts to stay the various requirements that the agency is currently reconsidering. Judicial review of EPA's attempts to stay rules in effect could more broadly impact the Trump Administration's efforts to similarly stay other rules that are under reconsideration.
This report examines the statutory authority for issuing the methane regulations, legal challenges to the standards, and legal issues related to the reconsideration and stay of the regulations.