NR 140 Groundwater Quality Standards Update

By Jeff Ramey, Senior Project Manager, TRC Companies

On June 21, 2019, the Wisconsin Department of Health Services (DHS) provided recommendations for groundwater enforcement standards (ES) (https://www.dhs.wisconsin.gov/water/gws.htm) and preventive action limits (PAL) as requested by the Wisconsin Department of Natural Resources (DNR) for 27 groundwater contaminants (referred to as Cycle 10). This is the first time in the last ten years that the DNR has proposed new or revised groundwater standards. The DNR rule making process (https://dnr.wi.gov/topic/Groundwater/NR140.html) for Cycle 10 commenced in March of 2018 with the DNR’s formal request of DHS to provide groundwater recommendations and is expected to take up to 30 months to complete before enforceable standards will be promulgated. The DNR states in their press release that after promulgating groundwater quality standards that: “These standards are used for regulating facilities, practices, and activities that can affect groundwater. They apply to bottled water, approved agricultural chemicals, contamination site cleanup, regulation of solid waste landfills, and more.”

Of the 27 requested groundwater contaminants in Cycle 10, 16 contaminants are new and 11 are existing contaminants under Wis. Admin. Code NR 140. Notably, recommendations for standards for emerging contaminants, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), hexavalent chromium, and glyphosate (commonly known as Roundup™) were newly created by DHS and revisions were recommended for tetrachloroethylene (PCE) and trichlorethylene (TCE). Potentially significant to contamination site cleanup is DHS’s recommendation to reduce the ES and PAL for TCE by an order of magnitude.

DHS’s recommended ES of 20 ng/L (parts per trillion) for the sum of the concentrations of PFOS and PFOA is the lowest groundwater standard for these compounds in the nation (along with the State of Vermont). The recommended PAL for PFOS and PFOA of 2 ng/L will challenge analytical laboratories to achieve useable reporting limits for these compounds when other organic or inorganic compounds or contaminants are present using the current, modified, and future analytical methodology. The DNR’s NR 149 laboratory certification program has drafted the “WI PFAS SOP” with the requested input of 17 laboratories to create a standard procedure to report 36 per- and polyfluoralkyl substances (PFAS). The DNR plans to audit and certify laboratories for PFAS analysis later this summer.

Concurrently, the DNR has formally issued a request to DHS to provide groundwater recommendations for 40 additional contaminants (referred to as Cycle 11), including 34 additional PFAS that do not currently have NR 140 groundwater standards. The rule making process and timelines for Cycle 10 and Cycle 11 are separate processes with proposed end points for published and effective dates of Fall 2021 and Fall 2023, respectively. Each rule making procedure will follow an extensive process (https://dnr.wi.gov/new/input/documents/rules/AdminRuleProcedure.pdf ) for the promulgation of permanent rules that will include the opportunity for public input through public meetings and hearings, Natural Resources Board (NRB) meetings, and stakeholder input into the economic impact of the proposed rules in the required preparation of an economic impact analysis (EIA).

As of the time of this article, the DNR posts 22 cases where PFAS are listed as a substance in the Bureau for Remediation and Redevelopment Tracking System (BRRTS). Later this summer, DNR’s water quality bureau will conduct a water quality monitoring plan with the objectives of describing PFAS concentrations at sites with known or suspected contamination and collecting paired fish tissue and surface water samples. The testing will be conducted in Wisconsin waterbodies could lead to follow up actions by the DNR at potential PFAS sources along with providing data that will be used for potential fish consumption advisories and the deriving of surface water quality standards.

For more information on the current state of PFAS, register for the FET PFAS Updates and Strategies seminar on Tuesday, October 22nd. PFAS Updates and Strategies