The Oklahoma Department of Environmental Quality (DEQ) is revising Title 252 of the Oklahoma Administrative Code (OAC), which would affect the State’s water regulations. The proposed changes aim to incorporate United States Environmental Protection Agency (EPA) rulemaking activities, implement public feedback, and pave the way for carbon sequestration primacy. The DEQ’s proposed changes impact five chapters of the OAC’s Title 252.
Oklahoma Pollutant Discharge Elimination System (OAC252:606)
Public Water Operation (OAC252:631)
Underground Injection Control (OAC252:652)
Waterworks and Wastewater Works Operator Certification (OAC252:710)
Laboratory Services (OAC252:305)
In this article, we explain the proposed changes to the first four listed chapters and explore their potential impacts on entities subject to these regulations. The revisions to the Laboratory Services chapter are outside the scope of this article.
1. Oklahoma Pollutant Discharge Elimination System (OAC252:606)
Recent EPA rulemaking activities related to PFAS, power generation, test methods, and certification spurred the Oklahoma DEQ to propose four additions to the Oklahoma Pollutant Discharge Elimination System chapter of the OAC.
The first change would add regulations for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)—including their salts and structural isomers—to this chapter. This follows the EPA’s designation of PFOA and PFOS as “hazardous substances” under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). CERCLA, also known as Superfund, gives the EPA authority to regulate and clean up hazardous waste sites. Designating PFOA and PFOS as hazardous substances allows the Superfund program to become involved in waste sites where these chemicals are present.
Once a chemical is designated as hazardous, it is added to the Superfund (40CFR) Table 302.4. Any unplanned environmental release above the designated reportable quantity of 1 pound (lb) during a 24-hour period must be reported to the EPA’s National Response Center. In addition, hazardous substances may be subject to release tracking, permitting, manifesting, and reporting under various other federal and state programs.
Steam Electric Power Generating Effluent Guidelines and Standards
The Oklahoma DEQ’s second proposed addition to this chapter would revise the technology-based limits (i.e., discharge limits based on capabilities of pollution control technologies) under the EPA’s Steam Electric Power Generating Effluent Guidelines for wastewater from coal-fired plants that operate as utilities.
The changes would implement a zero-discharge policy for flue gas desulfurization wastewater, bottom ash transport water, and combustion residual leachate. They would also limit discharges via groundwater and legacy wastewater from surface impoundments.
Under the revisions, limits would be less strict for power plants that are closing or switching to less polluting fuels, like natural gas, by 2034. These plants would be able to continue following 2020 requirements.
The Oklahoma DEQ’s proposed revision to this chapter would impact effluent test procedures under the National Pollutant Discharge Elimination System (NPDES). This proposal is in reaction to the EPA updating its test procedures under the agency’s permit programs for analyzing industrial and municipal wastewater's chemical, physical, and biological properties.
Under the Oklahoma DEQ’s proposal, facilities must use EPA-approved analytical methods when applying for NPDES permits; when preparing sampling or other reports under NPDES permit requirements; and when gathering other effluent data to satisfy NPDES regulations, state CWA 401 certifications, and sampling and analysis requirements under the EPA’s General Pretreatment Regulations for Existing and New Sources of Pollution. The updated procedures would offer a range of measurement techniques, selection flexibility, and better cost control in meeting monitoring requirements while maintaining data quality.
Water Quality Certification
Oklahoma DEQ proposed a new water quality certification improvement rule that aims to provide a clear and consistent Clean Water Act (CWA) Section 401 certification process while protecting state, territory, and Tribal water resources. The CWA certification ensures that states and authorized Tribes have a role in protecting their water from impacts related to federally licensed or permitted projects.
The rule would allow stakeholders to engage in certification earlier in the process. It would also establish clear expectations for what information should be included in certification requests, limit the time to decide on water quality certification to one year, and allow modifications to certification with EPA approval.
2. Public Water Operation (OAC252:631)
The Oklahoma DEQ proposed changes to this chapter to update federal regulations from August 17, 2022, to July 1, 2024.
Other major rules such as the Lead and Copper Rule Improvements (LCRI), which was last amended on October 30, 2024, may also be incorporated into the chapter “by reference,” meaning “as is” without significant revisions to the original rule language. The LCRI specifies new requirements for public water treatment, corrosion control, lead service line inventory/replacement, public notice, monitoring for lead in schools and childcare facilities, and public education. This rule is a significant expansion of regulatory requirements affecting community water systems and non-transient, non-community water systems.
The Oklahoma DEQ also aims to update laboratory notifications to match Tier 1 public notice requirements, as well as public water supply immediate notification requirements, sampling data validation procedures, and Consumer Confidence Report delivery.
The agency’s proposed revisions would also remove total chlorine residual testing requirements for systems that use free chlorine since the latter is more representative of water safety and accommodates physical and cybersecurity concerns. Public water system security in Oklahoma aligns with the EPA’s program countering increases in cyber threats.
3. Underground Injection Control (OAC252:652)
The Oklahoma DEQ’s proposed changes in this chapter would impact Class VI well regulations related to geologic carbon dioxide sequestration. According to the Oklahoma DEQ, these changes are necessary for the EPA to give Oklahoma primary enforcement responsibility (primacy) over Class VI wells. The latter is specifically designed and used to inject carbon dioxide deep underground to reduce and counteract ambient emissions into the environment.
The changes include adding rule language citing Class VI wells, establishing fees for Class VI facilities, and creating a new subchapter detailing specific requirements for these wells.
The Oklahoma DEQ also aims to amend OAC 252:4, which details the Class VI injection well permit application process, to correspond with these proposed regulation changes.
Both the Oklahoma DEQ and the Oklahoma Corporation Commission (OCC) currently have joint statutory authority over Class VI wells. Going forward, OCC plans to create its own Class VI regulations.
4. Waterworks/Wastewater Operator Certification (OAC252:710)
The proposed updates to this chapter would clarify that the term “operator experience” means licensed experience as to ensure that licensure requirements are clear. They would also allow operator certification classes shorter than 4 hours to be virtual, establish a military exception for renewals, and create a format for training record submittals. The changes would also require annual adjustments to Consumer Price Index fees, which are currently adjusted every 5 years. Additionally, they would rename “registered helper” to “non-certified helper” and authorize the Oklahoma DEQ to determine if non-community and minor systems need an operator.
What’s Next
These changes could impact a range of entities subject to Oklahoma water regulations. The public can comment on the proposed changes from December 2, 2024, through January 7, 2025, the latter being the date of the Water Quality Management Advisory Council (WQMAC) hearing. Thereafter, the Environmental Quality Board will meet on January 21, 2025, to vote on the proposed changes prior to permanent rulemaking and incorporation into the Water Quality Management Plan. The public may make comments orally at the hearings or submit comments in writing by the end of the specified public comment period. Additional announcements about the proposed changes are posted on the DEQ’s website, the Oklahoma Register, and the Oklahoma Office of Administrative Rules’ website, which provides access to the proposed rules open to public comments. Title 252 drafts discussed herein can be accessed online.
