BENNINGTON — The state has updated its health advisory for drinking water to include test results for three additional industrial chemicals that are related to PFOA and PFOS.
A recent review also found that a handful of wells previously tested primarily for PFOA — all located in Pownal — are now considered above the state drinking water standard of 20 parts per trillion.
The Vermont Department of Health and the Agency of Natural Resources announced the change Tuesday morning. The advisory list adds three more PFAS (per- and polyfluoroalkyl) substances to PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid), both of which were found in water supplies in several Vermont communities after being discovered in Bennington in 2016.
The state Department of Environmental Conservation also announced Tuesday a pilot program to test for PFAS substances in 10 Vermont schools with on-site drinking water wells. Some of the substances are found in floor cleaning products, stripping chemicals and polishes that may have been used to maintain school floors.
Reviewed test results
Based on the new health advisory, the state recently reviewed all previous water test results involving the chemical group known as PFAS. In a few wells near a former industrial site in Pownal, the listed of PFAs have been pushed from below to above 20 parts per trillion.
Peter Walke, deputy secretary of the Agency of Natural Resources, said property owners will have their wells retested to confirm the results.
“We looked at all the data to see if any wells were impacted, and a limited number were,” said Walke.
He said the affected property owners were notified and offered bottled water. Other remediation responses, such as carbon filtering systems, could be considered.
Point-of-entry treatment filtering systems have been used in impacted homes and businesses in Bennington, Shaftsbury, Pownal and Clarendon. Walke said they are designed to remove all five listed PFA compounds.
Walke said the Pownal wells considered to be above 20 parts per trillion are near a former Warren Wire Co. facility that stood at the intersection of Center Street and North Pownal Road.
If a well tested at 15 parts per trillion of PFOA and one of the newly listed compounds raised that total figure above 20 ppt, the home owner was notified, he said. The standard now is the total of all five PFAS chemicals combined.
Extensive testing of wells around the state followed discovery in 2016 of PFOA contamination around industrial sites in Bennington and Pownal. Previous health department advisories only listed PFOA (used for decades in the manufacture of Teflon and other non-stick substances), and PFOS (an ingredient in firefighting foam).
The new advisory also lists PFHxS (perfluorohexane sulfonic acid), PFHpA (perfluoroheptanoic acid), and PFNA (perfluorononanoic acid).
Walke said state officials were already considering adding more PFA substances to the state advisory. But an ongoing series of summits organized by the federal Environmental Protection Agency to discuss responses to widespread PFAS contamination added focus to the issue of standards.
He said Massachusetts and Connecticut have taken similar regulatory steps.
Testing in schools
The pilot school testing program will begin this week as a partnership involving the DEC, the Department of Health and the Agency of Education.
According to a release from the health department, some studies show that these PFAS may affect growth, learning and behavior in babies and older children, lower a woman’s chance of getting pregnant, interfere with the body’s natural hormones, increase cholesterol levels, affect the immune system, and increase the risk of cancer.
Medical studies relating to PFOA found that exposure to the compound through drinking water was associated with high cholesterol, ulcerative colitis, thyroid disease, testicular cancer, kidney cancer and pregnancy-induced hypertension.
After the discovery of contamination in drinking water in Bennington, the DEC developed a statewide PFAS sampling plan to strategically investigate numerous sources of PFAS. DEC officials have tested several locations where PFAS was used, including wire coating facilities, semi-conductor facilities, battery manufacturing facilities, and airports.
A water sampling report on the DEC website provides an overview of the findings and offers a look ahead into additional work needed in the future.
Read the story on VTDigger here: Three more toxic chemicals added to drinking water advisory list.