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Effluent Guidelines

Steam Electric Power Generating Effluent Guidelines

""EPA promulgated the Steam Electric Power Generating Effluent Guidelines and Standards (40 CFR Part 423) in 1974, and amended the regulations in 1977, 1978, 1980, 1982, 2015 and 2020. The regulations cover wastewater discharges from power plants operating as utilities. The Steam Electric regulations are incorporated into NPDES permits.
 
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What is Steam Electric Power Generating?

Steam electric plants use nuclear or fossil fuels (such as coal, oil and natural gas) to heat water in boilers, which generates steam. The steam is used to drive turbines connected to electric generators. The plants generate wastewater in the form of chemical pollutants and thermal pollution (heated water) from their water treatment, power cycle, ash handling and air pollution control systems, as well as from coal piles, yard and floor drainage, and other miscellaneous wastes.

These activities are included within the following NAICS codes:
  • 221112 – Fossil Fuel Electric Power Generation
  • 221113 – Nuclear Electric Power Generation

Note: the NAICS group listings are provided as a guide and do not define the coverage of the Steam Electric regulations. For precise definitions of coverage, see the applicability sections in 40 CFR Part 423.


Facilities Covered

The Steam Electric Power Generating Effluent Guidelines apply to a major portion of the electric power industry. These are plants primarily engaged in the generation of electricity for distribution and sale which results primarily from a process utilizing fossil-type fuel or nuclear fuel in conjunction with a thermal cycle employing the steam water system as the thermodynamic medium. There are approximately 914 of these facilities located throughout the United States.


2020 Reconsideration Rule

EPA revised the requirements for two waste streams: flue gas desulfurization (FGD) wastewater and bottom ash (BA) transport water; revised the voluntary incentives program for FGD wastewater; added subcategories; and established new compliance dates.

2015 Final Rule - Amendment

The 2015 final rule sets the first federal limits on the levels of toxic metals in wastewater that can be discharged from power plants.

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Background Documents

2009 Detailed Study

EPA conducted a study which provided an industry overview, data on wastewater characteristics of coal-fired plants, a description of applicable wastewater treatment technologies, a discussion of trends in the use of air pollution controls, and a description of environmental impacts.

Laboratory Analysis of Flue Gas Desulfurization (FGD) Wastewater


Rulemaking History

2020 Amendment

2015 Amendment

1982 Amendment

Revised BPT, BAT, BCT, NSPS, PSES and PSNS requirements
  • Documents, including:
    • Final Rule (November 19, 1982)
      • Development Document
        Industry description, wastewater characterization, treatment technologies, regulatory compliance cost estimates and pollutant loadings for the final rule
    • Proposed Rule (October 14, 1980)

1978 and 1980 Amendments

Amended BPT variance clause
  • Documents, including:
    • Final Rule (September 17, 1980)
    • Final Rule (September 29, 1978)

1977 Amendment

Established PSES requirements
  • Documents, including:
    • Final Rule (March 23, 1977)
      • Development Document (Pretreatment Supplement)
    • Proposed Rule (October 8, 1974)

1974 Initial Rulemaking

Established BPT, BAT, NSPS and PSNS requirements
  • Documents, including:
    • Final Rule (October 8, 1974)
      • Development Document
        Industry description, wastewater characterization, treatment technologies, regulatory compliance cost estimates and pollutant loadings for the final rule
    • Proposed Rule (March 4, 1974)

Additional Information

For additional information regarding Steam Electric Power Generating Effluent Guidelines, please contact Richard Benware (benware.richard@epa.gov) or 202-566-1369.

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