MASSDEP SETS MCL FOR PFAS IN DRINKING WATER

 

Simultaneously, MassDEP issued a notice to all public water suppliers (PWS) indicating the final regulations will be published and go into effect on October 2, 2020.

 

The final version of the MCL, which will be part of the revised drinking water regulations at 310 CMR 22.00, mirrors the draft regulations that were disseminated for public comment in December 2019 and establishes a Total PFAS MCL of 20 parts per trillion (ppt) for the sum of six PFAS compounds: PFOS, PFOA, PFHxS, PFNA, PFHpA, and PFDA. The regulations provide a new nickname for the group, the “PFAS6.”

 

The regulatory limit matches the revised Office of Research and Standards Guideline from January 24, 2020, but the new regulations also recognize that the scientific community’s understanding of the toxicological impacts from this broad class of synthetic compounds is still being developed. Section 310 CMR 22.07G(3)(e) of the final regulations directs MassDEP to “perform a review of relevant developments in the science, assessment and regulation of PFAS in drinking water for the purpose of evaluating whether to amend 310 CMR 22.07G(3) in light of any advancements in analytical or treatment technology, toxicology and/or any other relevant information” once every three years. Through this process, the PFAS concentration level could be changed and additional compounds could be added to the list of regulated contaminants in the future.

 

While the December 2019 draft MCL regulations anticipated the largest PWS serving more than 50,000 customers would begin quarterly monitoring by April 1, 2020, the COVID-19 pandemic hampered the agency’s ability to complete the regulatory review process. As a result, the final regulatory package was delayed and the Department set January 1, 2021 as the new monitoring start date for the largest PWS. The final regulations stagger the monitoring start date for PWS serving between 10,000 and 50,000 customers to April 1, 2021, and systems with less than 10,000 customers start monitoring on October 1, 2021.

 

In addition to unveiling the anticipated release of the final MCL regulations, the administration’s press release also announced the recipients of MassDEP’s PFAS Treatment Grants to support the design of treatment systems and reimburse costs and expenses for communities impacted by PFAS in drinking water. Ten water supply systems received grants of $200,000 from the PFAS Treatment Grant program.

 

In combination with the revisions that MassDEP made to the Massachusetts Contingency Plan in December 2019, which established reportable concentrations and cleanup standards for PFAS in soil and groundwater, this new MCL for PFAS in drinking water is another important step toward achieving a comprehensive regulatory framework for detecting and remediating PFAS in the Commonwealth. 

 

 

For more information:

 

John Shea’s newsletter article PFAS: From “Emerging Contaminants” to “Forever Chemicals” provides a survey of the regulatory history for PFAS in Massachusetts up through the draft MCL.

 

Peter Durning is a co-chair and moderator of an upcoming Environmental Business Council of New England (EBC) webinar with the leadership of the MassDEP Bureau of Water Resources on Wednesday, September 30, 2020. The speakers, including Assistant Commissioner Kathleen Baskin, and the Director of the Drinking Water Program, Yvette DePeiza, will certainly address this significant development in the drinking water regulations. Follow this link for more information and registration.