Company: EAI
Filing Date: 2025-02-18
Form Type: 10-K
Source: 0000065984-25-000012
Chunk: 118

Company: ENTERGY ARKANSAS, LLC
Filing Date: 2025-02-18
Form: 10-K
Item: Item 1A
Chunk 118
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 Engineers (Corps) subsequently issued a statement that the agencies would revert to pre-2015 regulations pending a new rulemaking.  In December 2022 the EPA and the Corps released a final definition of waters of the United States (the 2022 Rule) that replaces the NWPR with a definition that is consistent with the pre-2015 regulatory regime as interpreted by several United States Supreme Court decisions.  The 2022 Rule was subject to multiple legal challenges and was enjoined from implementation or enforcement throughout Entergy’s utility service territory.  In May 2023 the U.S. Supreme Court issued a decision limiting the scope of federal jurisdiction over wetlands, and in September 2023 the EPA and the Corps issued a final rule incorporating the Supreme Court decision.  Most notably, the exclusion for waste treatment systems is retained.

Effluent Limitation Guidelines

The 2015 Steam Electric Effluent Limitations Guidelines required, among other things, that there be no discharge of bottom ash transport water.  In 2020 the EPA finalized the Reconsideration Rule, allowing limited discharges of bottom ash transport water up to 10% of system volume, under certain defined circumstances including significant (10-year, 24-hour) rain events.  The 2020 rule also created a subcategory for units that permanently cease coal combustion by December 31, 2028.  Entergy’s White Bluff facility filed a notice of planned participation for this subcategory in October 2021.  In May 2024 the EPA finalized a supplemental rule that retains the “retirement by 2028” subcategory, creates a new “retirement by 2034” subcategory, otherwise reinstates the zero-discharge requirement for bottom ash transport water, and imposes new requirements for leachate after the facility ceases to burn coal.  Thus, units which permanently cease combustion of coal by December 31, 2028 or December 31, 2034 are exempt from the zero-discharge requirement.  However, for units in the 2034 subcategory, the 10% discharge allowance must be incorporated into the facility’s discharge permit.  To be covered by this exemption, both Independence and Nelson Unit 6 will need to file Notices of Planned Participation in the 2034 subcategory by December 31, 2025.  To help ensure facilities cease combustion of coal by the required subcategory 2028 and 2034 dates, zero discharge of bottom ash transport water is required after April