MassDEP says drinking-water program will lead rulemaking to align cleanup standards with EPA's new PFAS MCL

John Ziegler, MassDEP's statewide PFAS coordinator, told stakeholders that MassDEP's drinking-water program is taking the lead in updating Massachusetts drinking-water standards to reflect EPA's final PFAS maximum contaminant level rule, finalized June 25. "MassDEP's drinking water program is taking the lead in promulgating a Massachusetts drinking water standard that will be consistent with EPA's federal rulemaking," Ziegler said.

Ziegler said the changes will drive parallel revisions to MCP groundwater reportable concentrations (RCGW1) and method-1 GW1 standards but emphasized that the department's current MCP standards remain in effect while the Office of Research and Standards (ORS) completes a compound-by-compound review. He said the state expects to meet EPA standards but that the final PFAS list could include additional compounds identified by ORS.

Stakeholders raised concerns about the pace of rulemaking. "I would encourage...the Bureau of Waste [Cleanup] to do this earlier than the 2 years that you have under statutory regulations for EPA," said Susan Chapman, speaking in her advisory-committee role. Ziegler and other staff said the department is coordinating across bureaus to avoid public confusion and is seeking input from ORS before setting new imminent-hazard concentrations.

Ziegler said the agency is considering a downward adjustment to the current imminent-hazard threshold (now 90 nanograms per liter for the six PFAS compounds used in that benchmark) but that ORS must complete its review before a new numeric value is set. "So I think the expectation is that the imminent hazard concentration will adjust downward," he said.

MassDEP staff described next steps: issuance of a CAM protocol to support EPA method 1633 for PFAS analysis; updates to sampling-and-analysis guidance (last revised November 2023); and opportunities for public and practitioner comment as ORS completes its evaluation. Staff also flagged continued outreach, trainings and presentations at the AEHS Soils Conference at UMass Amherst on Oct. 21.

Millie, the meeting moderator, closed the update by noting ongoing legislative activity: "No, as you all know, the bill did not pass both the House and the Senate. It was not signed into law by the governor, so, therefore, it will need to be refiled for consideration next legislation." The department plans further stakeholder Q&A and guidance rollouts in coming months.

Next steps: ORS review of toxicity/compound list, a drinking-water rulemaking timetable led by the drinking-water program (potentially up to two years), and subsequent MCP updates to groundwater and soil standards where required.