State sets standards for PFAS in public water

Municipal supplies on-Island and across Massachusetts will be tested regularly.

Private wells were tested and carbon filters were installed upon the discovery of PFAS in 2019, but public water supplies did not yet have rigid standards for contaminant levels. — Brian Dowd

The state recently finalized regulations that establish enforceable standards for per- and polyfluoroalkyl substances (PFAS) in public drinking water systems.

According to Ron Myrick of Tetra Tech, the consulting and engineering services firm retained by the Martha’s Vineyard Airport that launched a mitigation effort to test and filter private wells that were affected by PFAS, public water supplies will be required to test for six of the main PFAS compounds.

PFAS is a fire retardant used in cookware and food packaging. In the case of Martha’s Vineyard Airport, PFAS contamination is linked to foam used for fighting jet engine fires.

According to MassDEP, exposure to the chemicals may cause developmental effects in fetuses during pregnancy, and in breastfed infants. Effects on the thyroid, the liver, kidneys, hormone levels, and immune systems have also been reported, according to MassDEP.

The new drinking water standard for PFAS establishes a limit of 20 parts per trillion (ppt) for the sum of six PFAS compounds, called “PFAS6.” The rule requires public water suppliers to test for PFAS6, and act when there is a detection above the state limit. There are currently no federal PFAS standards for drinking water.

Myrick said the state always intended to formulate a standard for PFAS in public water, but that process requires extensive review and consideration. “Going forward, PFAS will be on the list of compounds that public water suppliers in Massachusetts need to test for,” Myrick said.

He noted that his team and the airport have been using the 20 ppt regulation in testing private wells on-Island, but no public water supply standards were established at the outset of the mitigation effort, although he noted that municipal water supplies were tested for PFAS, and none were found to be at a high contaminant level.

During testing, Myrick and the Tetra Tech team discovered that PFAS had migrated through groundwater, coming from areas around the airport where aircraft fires had been extinguished, or where foam testing had taken place. Residential wells directly adjacent to the airport property were found to contain the highest concentrations of PFAS. The environmental consultants also dug test wells to test groundwater at various problem areas near the airport.

“Our administration is committed to ensuring that all residents have access to safe and clean drinking water,” said Gov. Charlie Baker in a press release. 

All community public water systems will be required to test for PFAS6. Large public water supplies, those serving a population of 50,000 or more, will be the first to test for PFAS6 under the new regulations, beginning their initial PFAS6 tests on Jan. 1, 2021. Public water supplies serving populations between 10,000 and 50,000 will begin initial tests April 1, 2021, and those serving a population of fewer than 10,000 will begin testing Oct. 1, 2021.