January 26, 2024. In North Carolina, adopting a new state rule involves many steps and multiple levels of review. But the rulemaking process has recently obstructed a water quality standard in ways not intended by the N.C. Administrative Procedure Act (APA). As a result, the rule setting a water quality standard for 1,4 dioxane — a toxic pollutant and likely human carcinogen — cannot go into effect even though there has been no legally supported objection to the rule.
1,4 dioxane. The U.S. Environmental Protection Agency (EPA) has identified 1,4 dioxane (used in solvents and other products) as a toxic pollutant associated with a number of adverse health effects, including liver damage and increased cancer risk. EPA published those findings in a 2020 health risk assessment of 1.4 dioxane that focused primarily on occupational exposure. In 2023, EPA released a revised health risk assessment of 1,4 dioxane considering risk to the public through exposure in drinking water. The new assessment concludes that 1,4 dioxane in drinking water “presents an unreasonable risk to human health”. (The revised assessment was released for public comment in September 2023; it is not clear whether EPA has finalized the assessment since closure of the comment period.)
As early as 2015, drinking water systems using the Cape Fear River system as a water source detected 1,4 dioxane in their drinking water. Those water systems include the Town of Pittsboro and the City of Fayetteville. Investigation of 1,4 dioxane releases to the river by the N.C. Department of Environmental Quality (DEQ) led to upstream municipal wastewater systems. As documented by DEQ, several cities — including Greensboro, Reidsville and Burlington — have periodically released wastewater containing high levels of 1,4 dioxane to the Cape Fear River system (which includes the Haw River). In most cases, the 1,4 dioxane could be traced back to a specific industrial facility discharging process water to the municipal sewer system.
As DEQ worked with these communities to address 1,4 dioxane spikes in their wastewater discharges, the N.C. Environment Management Commission (EMC) proposed and adopted a numerical water quality standard for 1,4 dioxane. A water quality standard establishes the safe concentration of a water pollutant in surface waters. DEQ permit writers then use the standard to set appropriate limits on wastewater discharge permits (National Pollutant Discharge Elimination System or “NPDES” permits) to maintain a safe level in the water. In developing the standard for 1,4 dioxane, the EMC relied on state and federal studies to calculate a safe concentration of 1,4 dioxane in surface water. The proposed state water quality standard of 0.35 micrograms per liter (or 0.35 parts per billion) aligned with the concentration EPA studies associated with higher cancer risk.
The EMC adopted the water quality standard for 1,4 dioxane standard in March 2022. Two years later, the 1,4 dioxane rule is still not in effect and it is not clear when or if it will be.
What went wrong? Once a state agency adopts a rule, the N.C. Rules Review Commission (RRC) must review and approve the rule before it can go into effect. Under the APA, the RRC can only object to a rule on four grounds:
1. The rulemaking agency didn’t have authority under state law to adopt the rule;
2. The rule language isn’t clear;
3. The rule isn’t reasonably necessary to implement state law or a federal law or rule;
4. The agency failed to comply with APA rulemaking procedures.
In May 2022, the RRC objected to the EMC’s 1,4 dioxane water quality standard. The RRC objection did not question the EMC’s authority to adopt the rule; the clarity of the standard; or the scientific basis for it. The objection was that the EMC failed to comply with APA rulemaking procedures because — in the opinion of the RRC — the fiscal analysis of the rule was flawed. But the APA does not allow the RRC to object to a rule based on the content of a fiscal analysis; the Office of State Budget and Management (OSBM) has responsibility for certifying the analysis. In fact, RRC staff legal counsel had previously advised the RRC that it did not have the authority to object to a rule based on the content of a fiscal analysis approved by OSBM.
As consistently interpreted and applied in the past (by the Rules Review Commission itself), the EMC complied with APA rulemaking requirements by submitting an OSBM-certified fiscal analysis. After unsuccessful efforts to resolve the RRC objection, the EMC authorized its legal counsel in September 2022 to challenge the RRC action in court as exceeding the RRC’s authority. At the time, the EMC voted by a nearly 2/3 majority to pursue judicial review of the RRC objection.
In January 2024 — after a turnover among EMC appointments — a new EMC majority appointed by legislative leaders and the Commissioner of Agriculture voted to drop the legal action challenging the RRC objection. Dismissing the lawsuit allows the RRC objection to stand and prevents the 1,4 dioxane standard from going into effect. There is no path around the RRC objection. Nothing in the APA supports the voiding of an environmental standard in the absence of any legitimate objection to the rule or the rule adoption process.
What next? Another version of the 1,4 dioxane standard (based on the most recent EPA health risk criteria) has been included in a new package of water quality rules the EMC just began to work on. EMC Chair J. D. Solomon has indicated an intent to move the 1,4 dioxane standard forward in that process. The problem is that the new rule will go through the same process as the original 1,4 dioxane standard — a process that required nearly two years for EMC adoption; additional months for RRC review; and resulted in the rule being voided nearly four years after the rulemaking process began based on an RRC objection lacking any basis in the Administrative Procedure Act. It is unlikely that the local governments opposed to the original 1,4 dioxane standard (as reflected in their comments to the Rules Review Commission when the rule was under review) will be more enthusiastic about the somewhat stricter standard in the new rulemaking package.
Meanwhile, DEQ continues to rely on the backstop of the “narrative” water quality standard in 15A NCAC 2B.0208 to address 1,4 dioxane. That rule provides specific direction to DEQ permit writers on how to set a water quality standard for a toxic pollutant that does not yet have a numerical standard in EMC rules. In recent years, DEQ has relied on the rule to set in-stream pollutant concentrations and then wastewater permit limits for 1,4 dioxane and PFAS chemicals. In another legal twist, however, the City of Asheboro has challenged the enforceability of 15A NCAC 2B.0208 in an appeal of conditions on Asheboro’s renewed NPDES permit — including conditions related to 1,4 dioxane. That case is pending in the Office of Administrative Hearings.
Postscript: Yesterday, the Raleigh News and Observer reported that the City of Burlington detected high 1,4 dioxane levels (545 parts per billion) in wastewater samples taken at the South Burlington Wastewater Treatment Plant on January 23, 2024. As noted above, EPA studies associated 0.35 ppb with a 1/1 million increased cancer risk and EPA has previously advised that 1,4 dioxane levels in drinking water should not exceed 35 ppb which correlates to a 1/10,000 increased cancer risk.
Burlington notified both DEQ and downstream water systems of the recent 1,4 dioxane spike (test results from the day before had been only 2.4 ppb) and contacted an industrial facility in Burlington suspected to be the source. The Town of Pittsboro, which has a drinking water intake in the Haw River downstream of the Burlington wastewater discharge, immediately reduced its Haw River withdrawal and asked Pittsboro water system customers to conserve water until the slug of 1,4 dioxane contaminated water passes the intake and concentrations of 1,4 dioxane at the intake drop to safe levels.