Final Rule - Legacy Coal Combustion Residuals Surface Impoundments and CCR Management Units
On this page:
Rule Summary
On May 8, 2024, EPA finalized changes to the CCR regulations for inactive surface impoundments at inactive electric utilities, referred to as "legacy CCR surface impoundments." Within tailored compliance deadlines, owners and operators of legacy CCR surface impoundments must comply with all existing requirements applicable to inactive CCR surface impoundments at active facilities, except for the location restrictions and liner design criteria.
This action is in response to the August 21, 2018 opinion by the U.S. Court of Appeals for the District of Columbia Circuit (Utility Solid Waste Activities Group, et al v. EPA) that vacated and remanded the provision that exempted inactive impoundments at inactive facilities from the April 17, 2015 CCR rule. These new regulations are also driven by the record, which clearly demonstrates that regulating legacy CCR surface impoundments will have significant public health and environmental benefits. This is because legacy CCR surface impoundments are more likely to be unlined and unmonitored, making them more prone to leaks and structural problems than units at utilities that are currently in service.
In addition, through implementation of the 2015 CCR rule, EPA found areas at regulated CCR facilities where CCR was disposed of or managed on land outside of regulated units at CCR facilities, referred to as “CCR management units.” Groundwater monitoring shows CCR management units pose risks to groundwater and human health and the environment. So, in this final rule, EPA established groundwater monitoring, corrective action, closure, and post closure care requirements for all CCR management units (regardless of how or when that CCR was placed) at regulated CCR facilities. This rule advances the agency’s commitment to protecting communities, groundwater, waterways, drinking water, and the air from CCR contamination.
- Read the final rule.
- Read the fact sheet for this final rule (pdf) .
- Read the press release.
- Read the list of Legacy CCR Surface Impoundments (pdf) .
- Read the list of CCR Management Units (pdf) .
- Read the list of CCRMU at other active facilities (pdf) .
- Access the May 2024 presentation about the final rule (pdf) .
Technical Corrections
On November 8, 2024, EPA published a direct final rule and companion proposed rule to correct errors in the May 2024 Legacy CCR Surface Impoundments final rule. The changes reflected in the direct final rule and companion proposal are:
- Fixing an error that caused confusion regarding the November 8, 2024 effective date of the Legacy Final Rule.
- Correcting inadvertent deletions in existing 2015 regulatory text caused by incorrect amendatory instructions.
EPA did not receive adverse comments by December 9, 2024, so the direct final rule went into effect on February 6, 2025.
Second Technical Corrections Rule
On January 16, 2025, EPA published a second direct final rule and companion proposed rule to correct errors and clarify several provisions in the May 2024 Legacy CCR Surface Impoundments final rule. The changes reflected in the direct final rule and companion proposal are:
- Fixing incorrect regulatory text citations and cross-references.
- Clarifying and adding provisions in the regulatory text to match what is clearly described in the preamble of the May 8 rule.
- Improving rule implementation by adding a new section consolidating compliance deadlines for CCRMU.
On March 14, 2025, EPA withdrew the direct final rule because we received adverse comment on it before the end of the comment period, March 17, 2025. The direct final rule would have gone into effect May 16, 2025. EPA still accepted public comments on the rule through March 17, 2025. EPA will respond to comments as part of any final action we take on the parallel proposed rule. As stated in the direct final rule and the parallel proposed rule, EPA will not institute a second comment period on this action. EPA is not reconsidering, proposing to reopen, or otherwise soliciting comment on any provisions of the Legacy CCR Surface Impoundments final rule or the CCR regulations.
- Access the direct final rule.
- Access the proposed rule.
- Access the withdrawal of the direct final rule.
Rule History
2015 Final Rule
In April 2015, EPA finalized national regulations to provide a comprehensive set of requirements for the safe disposal of coal ash from coal-fired power plants. These regulations include technical standards that prevent the leaking of contaminants into groundwater, blowing of contaminants into the air as dust, and catastrophic failure of coal ash surface impoundments. Additionally, the rule sets out inspection, monitoring, recordkeeping, and reporting requirements and makes transparency a cornerstone of the program by requiring facilities to post compliance data online on a facility-established, publicly available website.
The 2015 rule imposed requirements on inactive surface impoundments at active facilities, but did not impose requirements on inactive surface impoundments at inactive facilities. Several parties challenged the 2015 rule including, among other provisions, the exemption for inactive surface impoundments at inactive power plants from regulation.
The U.S. Court of Appeals for the D.C. Circuit issued its decision on August 21, 2018. The Court held that EPA acted “arbitrarily and capriciously and contrary to RCRA” in exempting inactive surface impoundments at inactive power plants from regulation. The court ordered that these provisions be vacated and remanded back to the Agency (Utility Solid Waste Activities Group, et al. v. EPA, 901 F.3d 414, D.C. Cir. 2018).
Advance Notice of Proposed Rulemaking
In October 2020, EPA requested comments and data on inactive surface impoundments at inactive electric utilities to assist in the development of future regulations for these CCR units. EPA requested input on a potential definition of a legacy CCR surface impoundment and specifically solicited information on the types of inactive surface impoundments at inactive facilities that might be considered legacy surface impoundments. Finally, the Agency took comment on EPA's regulatory authority, the appropriate regulatory approach for these units and the timeframes to come into compliance with those regulations.
Proposed Rule
On May 18, 2023, EPA proposed changes to CCR regulation for legacy CCR surface impoundments and CCR management units. EPA collected public comments on the proposal through July 17, 2023. EPA hosted an in-person hearing and an online public hearing.
- Read the proposal.
- Read a fact sheet about this proposal:
- Access the May 2023 press release announcing the proposal.
- Read through the comments submitted for this proposal.
- Access a transcript of the in-person hearing in the docket.
- Access a transcript of the online public hearing in the docket.
Notice of Data Availability
On November 7, 2023, the EPA Administrator signed a notice of data availability related to this proposed rule. EPA made available new information and data pertaining to the Agency’s May 18, 2023 proposed changes about legacy CCR surface impoundments and CCR management units. Some of the information includes data or analyses received during the comment period for the proposed rule and that could support the development of the final rule. It also includes information obtained based on further EPA research conducted both during and after the close of the comment period, which was not available for public comment during the prior comment period on the proposed rule.
EPA welcomed public comment on this additional information through December 11, 2023.
- Access the notice.
- Draft Supplemental Risk Assessment, October 2023.
- Groundwater Modeling Input and Output Files (Attachments C-1 and C-2):
- Attachment C-1: EPA Composite Model for Leachate Migration with Transformation Products inputs and associated outputs for impoundments (zip)(260.533 MB).
- Attachment C-1: EPACMTP inputs and outputs for landfills (zip)(116.585 MB).
- Attachment C-2: EPACMTP inputs for CCR management unit fills (zip)(61.534 MB).
- Attachment C-2: EPACMTP outputs for CCR management unit fills (zip)(44.677 MB).
- Groundwater Modeling Input and Output Files (Attachments C-1 and C-2):