On April 17, 2015, the Environmental Protection Agency (EPA or the Agency) promulgated national minimum criteria for existing and new coal combustion residuals (CCR) landfills and existing and new CCR surface impoundments. On August 21, 2018, the D.C. Circuit Court of Appeals issued its opinion in the case of Utility Solid Waste Activities Group, et al v. EPA, which vacated and remanded the provision that exempted inactive impoundments at inactive facilities from the CCR rule. EPA is developing regulations to implement this part of the court decision for inactive CCR surface impoundments at inactive utilities, or “legacy units.” This proposal may include adding a new definition for legacy CCR surface impoundments. EPA may also propose to require such legacy CCR surface impoundments to follow existing regulatory requirements for fugitive dust, groundwater monitoring, and closure, or other technical requirements. Finally, EPA is proposing corrective action requirements for all CCR contamination (regardless of how or when that CCR was placed) at a regulated facility.