February 23, 2025. The previous post addressed the human health risks associated with 1,4 dioxane. Two approaches to limiting the release of 1,4 dioxane to North Carolina drinking water sources have been blocked in the last two years.  For almost 50 years, an existing EMC rule (often referred to as the “narrative standard”) has been used to limit the discharge of a toxic water pollutant if  the EMC has not yet adopted an individual rule setting a water quality standard for the pollutant.   That rule has recently been the subject of legal challenges.  Several North Carolina cities that contested  use of the narrative standard  to limit 1,4 dioxane releases also opposed EMC adoption of a rule setting a water quality standard for 1,4 dioxane.  As described below, the result has been an administrative court order barring use of the narrative standard to limit discharge of 1,4 dioxane; a stymied effort to adopt a rule setting an individual water quality standard for 1,4 dioxane; and the loss (at least in the short term) of any effective means to regulate discharge of  1,4 dioxane to North Carolina drinking water sources.  

Challenges to the “Narrative Standard” for Toxic Water Pollutants. An existing water quality rule,  15A NCAC 2H.0208, directs the Department of Environmental Quality (DEQ)  to ensure that

The rule (often referred to as the  “narrative standard”) goes on to set out specific methods for calculating the allowable concentration of a toxic substance in surface waters based on toxicity or association with increased cancer risk. The EMC uses the same methods set out in 15A NCAC 2H.0208 to develop and adopt a rule setting the water quality standard for an individual toxic pollutant. The “narrative standard” establishes the equations to be used in calculating the concentration of  a toxic water pollutant that would protect human health; an EMC rule setting  the water quality standard for an individual toxic pollutant reflects the number that results from those same equations.

The U.S. Environmental Protection Agency (EPA) requires every state that issues federal Clean Water Act (CWA) permits for wastewater discharges  — National Pollutant Discharge Elimination System (NPDES) permits — to adopt a version of the narrative standard.  The standard exists specifically to address new pollutants or new information about health and environmental risks associated with known pollutants. In the absence of the narrative standard, the state would have no clear, predictable and timely method for limiting release of a newly identified toxic and/or cancer-causing pollutant.  The state process for adopting a rule setting a water quality standard for an individual pollutant takes a minimum of  2-3 years, but can and often does take longer. The N.C. “narrative standard” rule has been in place since  EPA approved the state’s NPDES permitting  program in 1976.  

The City of Asheboro’s wastewater treatment system discharges to a tributary of the Cape Fear River which is a drinking water source for a number of downstream communities. After monitoring data showed periodically high levels of 1,4 dioxane in Asheboro wastewater discharges, DEQ added a 1,4 dioxane limit to the city’s NPDES permit in 2023. The permit gave the city an initial permit limit of 55.7 parts per billion (ppb) and required phased reductions over five years to a final limit of 21.58 ppb. The final permit limit reflected the concentration of 1,4 dioxane at the discharge point that would allow downstream drinking water sources to meet the health based standard calculated under 15A NCAC 2H.0208.  

The City of Asheboro appealed the 1,4 dioxane permit limit.  The cities of Greensboro and Reidsville, which have also been sources of periodically high 1,4 dioxane releases, joined the appeal in support of Asheboro.  The cities argued that an NPDES permit limit  must be based on a rule setting a  numerical water quality standard for the individual pollutant and cannot be based on a toxic pollutant standard calculated under 15A NCAC 2H.0208. 

In September 2024, Chief Administrative Law Judge (ALJ) Donald van der Vaart ruled in favor of the cities. The decision held that DEQ lacked authority to impose a permit limit based on an in-stream standard for a toxic pollutant calculated under 15A NCAC 2H.0208.  Alternatively, the ALJ held that  DEQ misapplied the “narrative standard” by treating 1,4 dioxane as a human carcinogen and calculating the in-stream value based on carcinogenicity. The order voided the 1,4 dioxane limit on the City of Asheboro NPDES permit.

The failed attempt to set a water quality standard for  1,4 dioxane by rule.  In 2022, the EMC adopted a rule setting a numerical water quality standard for 1,4 dioxane. The rule could not  go into effect unless the N.C.  Rules Review Commission (RRC)  approved it under four criteria set out in G.S. 150B-21.1.  The rule must be:

1. Within the authority delegated to the agency by the General Assembly.

2. Clear and unambiguous.

3. Reasonably necessary to implement or interpret an enactment of the General Assembly, or of Congress, or a regulation of a federal agency…and

4. Adopted in accordance with the Administrative Procedure Act (APA)  rule-making process.

Since the APA requires a fiscal analysis for certain types of rules,  the fourth criteria allows the RRC to disapprove a rule based on agency failure to prepare a required fiscal analysis. 

Several cities  submitted comments to the RRC  opposing  the 1,4 dioxane standard proposed by the EMC in 2022. The RRC ultimately objected to the 2022 1,4-dioxane rule based on the fourth criteria — that the EMC failed  to adopt the rule in accordance with APA rule-making requirements. The specific objection was that the fiscal analysis of the rule was inadequate. The  RRC objection prevented the rule from moving through the final steps required for the 1,4 dioxane standard to go into effect. 

In September 2022, the EMC voted to appeal the RRC objection to Superior Court on the grounds that the RRC had no authority to object to a rule based on the content of the fiscal analysis. G.S. 150B-21.4 gives the Office of State Budget and Management (OSBM) authority to approve or disapprove the fiscal analysis of a proposed rule.  The  EMC appeal argued that the EMC  fully complied with APA rulemaking requirements by submitting an OSBM-certified fiscal analysis for the 1,4 dioxane rule.   The appeal took several twists and turns,  including voluntary dismissal of the initial appeal petition for technical reasons and months of settlement negotiations with the RRC. In early November 2023,  EMC legal counsel re-filed the appeal petition in Superior Court in the expectation that the case could be resolved quickly based on a settlement  that would withdraw the RRC objection.

The 1,4 dioxane rule  then became caught up in legislative changes in appointments to the EMC. Under Session Law 2023-136, the political makeup of the EMC shifted from a majority of governor’s appointees to a majority appointed by legislative leaders and the Commissioner of Agriculture. As a result, the EMC flipped from a Democratic to a Republican majority. The law also removed the Governor’s power to appoint the EMC chair, requiring that the chair be elected from among the members. The new Republican majority elected legislative appointee J.D. Solomon as chair at the November 2023 EMC meeting.  

Although the EMC’s legal counsel reportedly advised Chair Solomon in November 2023 that a settlement agreement with the RRC was being drafted, no settlement was ever finalized and EMC members never received any update on conclusion of settlement negotiations. In January 2024, the new EMC majority  voted to dismiss the appeal entirely on the recommendation of Chair Solomon. Dismissal of the appeal allowed the objection to the 1,4 dioxane rule to stand and prevented the proposed rule from moving forward. 

State of Play. As noted above, a Rules Review Commission objection prevents a proposed rule from moving through the final steps necessary for  the rule to go into effect. The EMC decision to dismiss  the appeal of the RRC objection in January 2024 allowed the objection to  stand and prevented the rule from going into effect. Since then,  the EMC has taken no steps toward adoption of a rule setting a numerical standard for 1,4 dioxane.  

DEQ has appealed the ALJ ruling on the City of Asheboro NPDES permit. In the meantime, DEQ complied with the decision  by issuing a revised permit with no 1,4 dioxane limit in November of 2024.  A few weeks ago, water quality monitoring found that levels of 1,4 dioxane released by the City of Asheboro had increased exponentially since modification of the permit. A DEQ press release reported concentrations of 2200 ppb in Division of Water Resources (DWR) samples taken from the Asheboro discharge on January 25, 2025 — 100X the proposed final NPDES permit limit of 22 parts per billion. Samples taken by the city showed  concentrations as high as 3500 parts per billion. A DWR graph shows the dramatic increase in the monthly average 1,4 dioxane concentration in the Asheboro wastewater discharge 

Note: I am a current governor’s appointee and past chair of the EMC.  The post reflects my analysis of the rulemaking history and does not represent those of the  EMC as a body or any of its members.