This study was done by the STEEP Superfund Research Program at the University of Rhode Island and was a collaborative effort with the Harvard T.H. Chan School of Public Health, the state Department of Environmental Health, and the Silent Spring Institute. Results showed that 46% of the 101 private wells tested had at least one PFAS chemical detected, while 28% of wells had two or more PFAS chemicals detected. Fortunately, only 3% of wells showed levels higher than the proposed groundwater standards for Massachusetts, which limit PFAS contamination to 20 parts per trillion for six chemicals.
While the study did not identify a source of PFAS entering well water, STEEP researcher Laurel Schaider noted, “wells with more nitrates tended to have high PFAS.” The number of wells with detectable PFAS levels was highest near Mid-Cape, 61%, and lowest near Lower Cape, 32%.
Sampling for this study so far was done in August, September, November, and December of 2018. By the end of the five-year project, STEEP plans to have sampled 250 wells with another round of well testing planned for this winter. The research team also plans to test for PFAS at possible sources of exposure, such as landfills and firefighting training areas.
This study tested for 25 different PFAS chemicals, detecting 9 of which at least once. The state of Massachusetts lists five PFAS chemicals in its current drinking water guideline for the state, however this study detected the presence of several PFAS chemicals not on the list. Not all PFAS chemicals are well understood and this study demonstrates the importance of further investigation into where these chemicals come from and what exposure to these chemicals means.