[20200817]IF11622_汞和空气毒物法规的司法审查.pdf

https:/crsreports.congress.gov August 17, 2020Judicial Review of Mercury and Air Toxics RegulationsSince 1990, the U.S. Environmental Protection Agencys (EPAs) efforts to regulate mercury and other hazardous air pollutants (HAPs or air toxics) emitted by power plants have faced numerous legal challenges. The Clean Air Act (CAA) Amendments of 1990, Pub. L. 101-549, established a multistep process for EPA to regulate HAP emissions from fossil fuel-fired electric utility steam generating units (i.e., power plants). One of those steps requires EPA to regulate HAP emissions from power plants if the agency determines that it is “appropriate and necessary” to do so. Stakeholders have challenged each of EPAs “appropriate and necessary” findings and other actions to regulate HAP emissions from power plants. Most recently, litigants are challenging EPAs May 2020 rule that concluded that HAP emission limits for coal- and oil-fired power plants are not “appropriate and necessary” under the CAA (2020 Appropriate and Necessary (A&N) Rule, 85 Fed. Reg. 31,286, May 22, 2020). This rulemaking reversed a prior EPA-issued rule that such limits were appropriate and necessary, though EPA declined to r