The Guardian newspaper teamed up with Consumer Reports to sample 120 water systems in the nation, and found that almost all of them — 118 of 120 — had detectable levels of lead, arsenic or PFAS chemicals found in household products from cookware to rugs.
Included in the report was a noteworthy test result from Shelburne that indicated PFAS levels of 5.77 parts per trillion. That’s well below the federal advisory level of 70 parts per trillion and Vermont’s more stringent 20 parts per trillion level.
But it is more than has been reported by the water system serving much of Shelburne, the Champlain Water District, raising questions about how the contaminant made it into the sample.
“We don’t have any PFAS detected in our source water,” said Joseph Duncan, general manager of the Champlain Water District.
The district delivers drinking water from Shelburne Bay to 75,000 people in eight towns, including South Burlington, Essex and Milton.
The district samples for PFAS both at its treatment plant on Queen City Park Road and at points in the water distribution network, but not in people’s homes, he said.
Tests performed in 2019 and in 2020 both came back as “non-detect,” meaning the sample has less than 2 parts per trillion, and the five PFAS compounds Vermont regulates were considered not detected. The Guardian story also included a result of 1.74 parts per trillion from Bennington, but that falls below what is considered detectable by the state.
Complicating the issue is that the sampling regimen utilized by the publications relied on volunteers, and the conditions under which the water sample was taken could not be confirmed.
PFAS chemicals are prevalent in clothing and a range of consumer goods, and sampling must be done with precision, Duncan noted.
“At the parts-per-trillion level, you have to be very careful with how you collect the sample in order to not cross-contaminate it and wind up with a false positive,” Duncan said.
He stressed he was not questioning the competence of the volunteers or the value of the reporting, and said he supports greater public awareness of water quality issues. Nevertheless, a single data point from an unknown origin that doesn’t align with the district’s own regular sampling results makes drawing…