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Water: Oil & Gas Extraction

Oil and Gas Extraction Effluent Guidelines


EPA promulgated the Oil and Gas Extraction (O&G) effluent guidelines and standards (40 CFR Part 435) in 1979, and amended the regulation in 1993, 1996, and 2001. The regulation covers wastewater discharges from field exploration, drilling, production, well treatment and well completion activities. These activities take place on land, in coastal areas and offshore. The O&G effluent guidelines and standards are incorporated into NPDES permits.  The regulations apply to conventional and unconventional oil and gas extraction with the exception of coalbed methane.

What is the Oil and Gas Extraction Industry?

Oil and Gas Extraction is the exploration and production of petroleum and natural gas from wells. The industry generates wastewater from the water extracted from the geological formations and from chemicals used during exploration, well drilling and production of oil and gas.

These activities are included within North American Industrial Classification System (NAICS) code 211111, Crude Petroleum and Natural Gas Extraction. (Note: the NAICS group listings are provided as a guide and do not define the coverage of the O&G rule. For precise definitions of coverage, see the applicability sections in 40 CFR Part 435.)

Facilities Covered

The O&G regulation applies to facilities organized into 5 subcategories:

  • Subpart A: Offshore
  • Subpart C: Onshore
  • Subpart D: Coastal
  • Subpart E: Agricultural and Wildlife Water Use
  • Subpart F: Stripper Wells

Wastestreams Covered

  • Produced water
  • Produced sand
  • Drilling fluids
  • Drill cuttings
  • Well treatment, workover and completion fluids
  • Domestic*
  • Sanitary*
  • Deck drainage*
* Subparts A and D only

Subpart C Amendments: Unconventional Extraction

EPA has issued a proposed rule (March 31, 2015) to address wastewater pollutant discharges from onshore unconventional oil and gas extraction facilities to municipal wastewater treatment plants.

Coalbed Methane

EPA has not promulgated effluent limitations guidelines and standards for pollutant discharges from coalbed methane extraction facilities.  EPA had initiated a coalbed methane rulemaking, but announced its decision to discontinue this effort in Fall 2014.

Rulemaking History

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.

Additional Information

For additional information on existing Oil and Gas Extraction subcategories, please contact Ron Jordan (jordan.ronald@epa.gov) or 202-566-1003.  For additional information on Unconventional Extraction, please contact Lisa Biddle (biddle.lisa@epa.gov) or 202-566-0350.

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