[20200519]IF11078_环保局重新考虑汞和空气毒物限制的好处.pdf

https:/crsreports.congress.gov Updated May 19, 2020EPA Reconsiders Benefits of Mercury and Air Toxics LimitsIn April 2020, the U.S. Environmental Protection Agency (EPA) concluded that limits on hazardous air pollutants (HAPs) from coal- and oil-fired power plants are not “appropriate and necessary” (A&N) under Clean Air Act (CAA) Section 112(n)(1) (“Reconsideration of Supplemental Finding and Residual Risk and Technology Review,” April 16, 2020). The 2020 A&N rule reversed prior A&N determinations, which led to the 2000 listing of coal- and oil-fired power plants as a major source of HAPs and the 2012 Mercury and Air Toxics Standards (MATS) limiting those HAPs. Notwithstanding the 2020 A&N rule, the 2012 MATS limits remain in effect for power plants because EPA determined that it could not meet the criteria under CAA 112(c)(9) to delist them. Furthermore, the A&N finding does not change the regulatory status of other pollution sources because CAA Section 112(n)(1) applies only to power plants. Some have raised questions about why EPA reversed the A&N finding and how it might affect regulated entities. For example, some power plant owners are concerned the A&N reversal may comprom