Last week the Environmental Protection Agency set a nationwide standard for PFAS (per- and polyfluoro-alkyl substances)—more commonly known as “forever chemicals”—in drinking water. Public water supplies have five years to comply with the new regulations, which are stricter than the state’s. The latest tests on Harvard’s town water, supplied by two wells on Pond Road, passed all the new regulations, although one of the regulated substances passed by only three-hundredths of a milligram per liter.
While the state PFAS maximum contaminant level is 20 milligrams per liter (or parts per trillion) for the sum of six specific substances, the new federal regulation applies to single substances (see table). Concentrations of PFOA and PFOS, two of the more prevalent substances found in water in this area, may be no higher than 4 ppt each. Three other substances, PFHxS, PFNA, and HFPO-DA, cannot be over 10 ppt. Compliance with these regulations will be measured against the average test results in a year.
Water to residences and businesses in town center, as well as to the schools and municipal offices, is supplied by two wells (well #2 and well #5) located just off Pond Road. Both wells have been testing positive for PFAS since testing began in 2021, but results have always fallen below the state’s maximum permitted contaminant level.
Town wells testing just over or under new regs
But each of the Pond Road wells has tested over the limit for at least one of the substances in the EPA’s new regulation. Well #5 has routinely tested over 4 ppt for PFOA and PFOS since 2021. The most recent result for that well, from January 2023, showed a PFOA level of 4.72 ppt and a PFOS level of 4.38. Well #2 tested over 4 ppt for PFOA in only two of the six tests run in the past three years, but one test result showed a higher amount of PFOA, 5.23 ppt, than ever found in well #5.
Water from the two wells is currently blended, and the only blended test result available is from October 2023. In that test, the amount of PFOA in the blended water squeaked by under the new federal limits with a concentration of 3.97 ppt; PFOS was 3.43.
The presence of the other substances now regulated by the EPA in either well is currently minimal. PFNA and HFPO-DA were not detected in any test since 2021, and the highest level of PFHxS found in either well over the past three years was barely over 1 ppt.
Connecting Harvard’s town water to Devens
Fortunately, last year the town voted to fund a project to connect to the public water supply in Devens, where treatment of the three wells there has brought the most recent levels of every substance mentioned in the new EPA regulations to “non-detect.” Bids on that project were just opened, and the funding the town approved is not enough to cover the project (see story, page 2). Town officials are currently working on that problem.
The town planned to keep the Pond Road wells operational as a backup water supply after the Devens connection is complete. But the new regulations could make that tricky. While last year’s test results complied with the EPA limits, it was very close. It’s unclear what the EPA would require if a result went over the limit for only one year. And the state has yet to weigh in on whether it will adopt the federal regulations and how enforcement would work.
Trouble for other public water supplies?
The new maximum limits for contaminants will also spell trouble for other public water supplies in town. Water that serves Harvard Green condominiums, Foxglove Apartments, and Appleworks offices routinely tested over 4 ppt for PFOA in 2023, and Appleworks test results also exceeded the new federal limits for PFOS numerous times last year. Drinking water from the other public water supplies in town all tested within the EPA’s new regulations last year.
Public water supplies have three years to complete initial PFAS monitoring. The state already requires PFAS monitoring, and test results for all the public water supplies in Massachusetts are available on the Energy and Environmental Affairs Data Portal webpage.
Beginning in 2027, results must be reported to the public and regular compliance monitoring must begin. Two years later, systems must comply with the EPA’s new regulations.
