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Effluent Guidelines

2020 Steam Electric Reconsideration Rule

Steam Electric Power Generating Effluent Guidelines

""EPA, on August 31, 2020, finalized a rule revising the regulations for the Steam Electric Power Generating category (40 CFR Part 423). The rule revises requirements for two specific waste streams produced by steam electric power plants: flue gas desulfurization (FGD) wastewater and bottom ash (BA) transport water.

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In 2015, EPA issued a final rule that set the first federal limits on the levels of toxic metals in wastewater that can be discharged from power plants. That rule was subject to legal challenge and the agency received two petitions for administrative reconsideration, including one from the U.S. Small Business Administration’s Office of Advocacy. In response, EPA agreed to reconsider the Effluent Guidelines for two waste streams. This 2020 rule contains the final revised regulations for those two waste streams.


EPA hosted a public webinar on Thursday, November 5, 2020. Slides of the presentation are now available and a transcript of the presentation will be posted soon.

Affected Facilities

Only those coal fired power plants that discharge bottom ash transport water or FGD wastewater may incur compliance costs under the 2020 final rule. EPA estimates that 75 plants may incur compliance costs under the final rule, in an industry population of 914 plants.

Regulatory Requirements

The 2020 final rule:

  • Changes the technology-basis for treatment of FGD wastewater and BA transport water.
  • Revises the voluntary incentives program for FGD wastewater.
  • Adds subcategories for high-flow units, low utilization units and those that will transition away from coal combustion by 2028 and finalizing requirements that are tailored to facilities in these subcategories.
  • Establishes new compliance dates.

2020 Final Rule Documents


Documents related to the rulemaking can be found on EPA’s docket at The Docket Number is EPA-HQ-OW-2009-0819.

Related Rulemaking

2019 Proposed Reconsideration Rule

Additional Information

For additional technical information about the 2020 final rule, please contact Richard Benware ( or 202-566-1369. For economic information please contact James Covington ( or 202-566-1034.

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