The U.S. Environmental Protection Agency (the EPA or the Agency) is entrusted with protecting human health and safeguarding the natural environment — air, water, and land. The EPA works with other federal agencies, state and local governments, and Indian Country governments to develop and enforce regulations under existing environmental laws. The EPA, which is responsible for researching and setting national standards for a variety of federal environmental programs, has in many cases approved State and Tribal programs for issuing permits and monitoring and enforcing compliance. Where national standards are not met, the EPA can issue sanctions and take other steps to assist the States and Tribes in reaching the desired levels of environmental quality. In the absence of primacy approval, programs are managed through the EPA's regional offices. In addition to the various Headquarters program offices, the EPA maintains 10 regional offices and 17 laboratories across the country.

Contact

• U.S. Environmental Protection Agency
  Standard Mail:
  Ariel Rios Building
  1200 Pennsylvania Avenue, N.W.
  Mail Code 3213A
  Washington, DC 20460
  (202) 272-0167 (phone)
  
  Overnight Package Delivery:
  EPA East
  1201 Constitution Avenue, N.W.
  Room Number 4101 M
  Washington, DC 20004

Produced Water Management Practices and Applicable Regulations

Discharge Operations — The Clean Water Act (CWA) requires that all discharges of pollutants to surface waters (streams, rivers, lakes, bays, and oceans) must be authorized by a permit issued under the National Pollutant Discharge Elimination System (NPDES) program. The two basic types of NPDES permits issued are individual and general permits. Individual NPDES permits are specifically tailored to individual facilities. General NPDES permits cover multiple facilities within a certain category located in a specific geographical area. The EPA has published federal NPDES regulations under the CWA, and may authorize states—as well as Territories and Tribes—to implement all or parts of the national program. Once approved, a state gains the authority to issue permits and administer the program. However, the EPA retains the opportunity to review the permits issued by the state, and formally object to elements deemed in conflict with federal requirements. The EPA's website depicts state program status. The EPA has not approved permitting authority for oil and gas in Texas, Oklahoma, New Mexico and Alaska, and still issues permits for produced water discharges in those states.

• Calculation of Effluent Limits — In order to meet the goals and requirements of the CWA, NPDES permit writers must consider two types of effluent limits when identifying effluent limits for produced water discharges: technology-based effluent limits and water quality-based effluent limits. Specifically, Federal regulations require NPDES permit writers to identify for each permitted wastewater discharge any applicable technology-based effluent limits (see 40 CFR 125.3). The permit writer must base the effluent limits in the permit on the more stringent of these two approaches. The permit writer can find these technology-based effluent limits in EPA and State regulations. In the absence of applicable national technology-based limits for an industrial wastewater or pollutant discharge (known as effluent limitations guidelines or "ELGs"), permit writers will use Best Professional Judgment (BPJ) to identify technology-based limitations on a case-by-case basis.
  
• Technology-based Effluent Limits — For oil and gas extraction operations, the EPA has codified national technology-based ELGs in the Code of Federal Regulations (CFR) at 40 CFR Part 435—Oil and Gas Extraction Point Source Category.
  
• Onshore — EPA established ELGs for the Oil and Gas Extraction point source category on 13 April 1979 (44 FR 22075). EPA imposed a zero-discharge requirement for all produced waters in the Onshore subcategory (40 CFR 435.32). Some onshore wells are not subject to this discharge prohibition.
  
  • Oil wells with very small production (i.e., stripper wells producing less than 10 bbl/day of oil) are not regulated by the Onshore subcategory but are regulated by the Stripper subcategory (40 CFR 435.60). The permitting authority will use best professional judgment (BPJ) and water quality standards to determine whether or not to allow the discharge of produced water and any appropriate effluent limitations.
    
  • Oil and gas wells located west of the 98 th parallel (roughly the western half of the United States) may be regulated by the effluent limits in the Agricultural and Wildlife Water Use subcategory (40 CFR 435.50) and may be able to discharge produced water if the following conditions are met:
    
    • The produced water must be used in agriculture or wildlife propagation when discharged into navigable waters (40 CFR 435.50); and
      
    • The produced water discharges must not exceed an oil and grease daily maximum limitation of 35 mg/L (40 CFR 435.52(b)).
      
  Additionally, EPA defined the term use in agricultural or wildlife propagation by stating "the produced water is of good enough quality to be used for wildlife or livestock watering or other agricultural uses, and the produced water is actually put to such use during periods of discharge." (40 CFR 435.51(c)). [Emphasis added].
  
• Coastal — Oil and gas activities located in coastal waters may not discharge produced waters, except for platforms located in Cook Inlet, Alaska (treated in the same manner as offshore waters, see below).
  
• Offshore — The ELGs for offshore wells establish limits for oil and grease of 29 mg/L monthly average and 42 mg/L daily maximum.
  
• Coal Bed Methane (CBM) — EPA did not consider CBM production in developing the 1979 national technology-based effluent limitations guidelines for the Onshore and Agricultural and Wildlife Water Use Subcategories of the Oil and Gas Extraction Point Source Category (40 CFR 435, Subparts C and E) because there was no significant CBM production in 1979. Accordingly, these ELGs do not apply to CBM produced water discharges. Permit writers will use BPJ to identify technology-based limitations on a case-by-case basis. The EPA announced in December 2006 that it would study the CBM industry during 2007–2008 to determine if additional ELGs were needed.
  

Regional General Permits
Four of the EPA's regional offices (4, 6, 9, and 10) have issued general permits to facilities discharging into ocean waters beyond the three-mile limit of the territorial seas and may also issue permits to facilities in the territorial sea if the adjoining State does not have an approved NPDES program. Regional NPDES permits establish slightly different effluent limits, monitoring, testing, reporting, and other operational or study requirements. These permits typically are issued for five-year terms.

• Region 4, Final NPDES General Permit for Offshore Oil and Gas Activities in the Eastern Portion of the Outer Continental Shelf of the Gulf of Mexico, GMG460000
  
• Region 6, Final NPDES General Permit for New and Existing Sources and New Dischargers in the Offshore Subcategory of the Oil and Gas Extraction Category for the Western Portion of the Outer Continental Shelf of the Gulf of Mexico, GMG290000
  
• Region 6, Final NPDES General Permit for Discharges from the Offshore Subcategory of the Oil and Gas Extraction Point Source Category to the Territorial Seas Off Texas, TXG260000
  
• Region 6, Final NPDES General Permit for Discharges from the Oil and Gas Extraction Point Source Category to Coastal Waters in Texas, TXG330000
  
• Region 9, Final General NPDES Permit for Offshore Oil and Gas Facilities Located in Federal Waters off the Coast of Southern California, CAG280000
  
• Region 10, General NPDES for Discharges from Oil and Gas Extraction Facilities in Federal and State Waters in Cook Inlet, AKG-31-5000
  
• Region 10, Arctic General Permit, AK 280000
  
  • Does not authorize produced water discharge.

Ocean Discharge Criteria Evaluation
Discharges into territorial seas, contiguous zones, and the oceans must undergo an additional level of review to ensure that they do not cause unreasonable degradation of the marine environment. The review is based on the EPA's ocean discharge criteria regulations codified in the Code of Federal Regulations (CFR) at 40 CFR Part 125.120 to 125.124.

Other NPDES Permit Conditions
Facilities are responsible for taking the steps necessary to demonstrate compliance with NPDES permit limits. Responsibilities include sampling, recordkeeping, reporting, and preparation of best management practices plans or spill prevention plans.

Injection Operations — Most onshore produced water is injected for either enhanced recovery or disposal. With the passage of the Safe Drinking Water Act (SDWA) in 1974, the subsurface injection of fluids came under Federal regulation. In 1980, the EPA promulgated the Underground Injection Control (UIC) regulations. The UIC program is designed to protect underground sources of drinking water (USDWs). A USDW is an aquifer or portion of an aquifer that supplies any public water system or contains sufficient quantity of groundwater to supply a public water system; currently supplies drinking water for human consumption or contains fewer than 10,000 mg/L total dissolved solids; and is not an aquifer exempted from UIC regulations. For purposes of regulatory control, the regulations distinguish between different classes of injection wells, including those associated with the production of oil and gas. The oil field injection wells are known as UIC Class II wells. The regulatory minimum requirements and technical criteria and standards govern permitting, area of review analysis, mechanical integrity, construction, operating, monitoring and reporting, and plugging and abandonment. The EPA's website shows drawings of typical injection wells of different classes.

The EPA has established minimum standards for state programs prior to receiving primacy for the UIC program under Section 1422 of the SDWA. In the wake of a congressional amendment, Section 1425 of the SDWA allows a state that seeks authority for oil-and-gas-related injection well programs to demonstrate a similar degree of effectiveness in protecting USDWs. The optional demonstration, which is only available for oil-and-gas-related injection well programs, covers various elements, including adequate oversight, record-keeping, and reporting. Because the Section 1425 approval route offers greater flexibility, most states that have obtained UIC primacy have opted to pursue this route. Tribes also follow the same rules for obtaining primacy if they are receiving "Treatment as a State" (TAS). The EPA's website reports that the Agency has approved program primacy for all well classes in 34 states, that it shares responsibility in six states, and that it directly implements the program for all well classes in 10 states (and in all of Indian Country). The Agency provides grant funds to all approved programs to help pay for program costs. States must provide a 25 percent match.

Exploration and Production Waste Exemption — In 1980, Congress conditionally exempted oil and gas exploration and production (E&P) wastes from the hazardous waste management requirements of Subtitle C of the Resource Conservation and Recovery Act (RCRA) (Section 3001(b)(2)(A) of RCRA and Section 8002(m) of RCRA). In addition to directing the EPA to study these wastes and submit a report to Congress on the status of their management, Congress required the Agency either to promulgate regulations under Subtitle C of RCRA or make a determination that such regulations were unwarranted. In 1988, the EPA published its Regulatory Determination for Oil and Gas and Geothermal Exploration, Development, and Production Wastes in the Federal Register (FR) at 53 FR 25447 (July 6, 1988). The EPA exempted wastes related to oil and gas exploration and production, including produced water, from the hazardous waste portions of the Resource Conservation and Recovery Act. The EPA rearticulated the exemption in the Code of Federal Regulations (CFR) at 40 CFR 261.4(b)(5) (click on retrieve by CFR citation enter: Title - 40, Part - 261, Section - 4). In 1993, the EPA published the Clarification of the Regulatory Determination for Wastes from the Exploration, Development and Production of Crude Oil, Natural Gas, and Geothermal Energy in the Federal Register (FR) at 58 FR 15284 (March 22, 1993). In 2002, the EPA published an information booklet entitled Exemption of Oil and Gas Exploration and Production Wastes from Federal Hazardous Waste Regulations. The federal E&P RCRA Subtitle C exemption, however, does not preclude these wastes from control under other federal and state regulations (including oil and gas conservation programs and some hazardous waste programs).

Additional Links Recommended by EPA

• EPA's Effluent Guidelines Website
• EPA's NPDES Permit Writers' Manual (EPA-833-B-96-003) (1996)
• EPA's Technical Support Document for the Preliminary 2008 Effluent Guidelines Program Plan (EPA-821R-07-007) (2007)
• EPA Office of Solid Wastes (OSW) Special Wastes
• EPA Office of Compliance Sector Notebook
• EPA TENORM Program
• Code of Federal Regulations
• Federal Register