A third private property in a Hanover neighborhood has tested positive for a chemical released from a former Dartmouth hazardous waste burial site.
In a letter to residents, Dartmouth said a house well tested .3 micrograms per liter for the chemical 1,4-dioxane. That is below the state-allotted level for the chemical in ground water at 3 micrograms per liter.
However, Dartmouth College is providing those homeowners with bottled water, a point-of-entry treatment system and a health consultant.
This comes just over a year after it was discovered that the chemical 1,4-dioxane, a probable human carcinogen, had gotten into the groundwater and run off the Rennie Farm property.
During the 1960s and '70s, Dartmouth College research labs were burying hazardous waste materials, including radioactive animal carcasses, scintillation fluid and lab refuse in a hilltop land plot. 1,4-Dioxane is a chemical that was often used in scintillation fluid cocktails during the mid-20th century.
In an email to neighbors, Maureen O’Leary, Dartmouth's director of environmental health & safety, said the contamination has reached further than initially expected, at nearly a mile away from the Rennie Farm burial plot.
“Although the detection of 1,4-dioxane this far from the site was not considered likely, we recommended homeowner well sampling in that area as a precaution,” she wrote in an email late Monday afternoon. “We are now working with the property owners to investigate how the 1,4-dioxane contamination reached the well and to verify the source, which we believe to be the Rennie Farm property.”
At a community meeting Tuesday night at the Rennie Farm burial site, concerned neighbors gathered to discuss their drinking water.
Amy Nichols said she was shocked when she heard the news. She lives just yards away from the property most recently discovered to have been contaminated.
"We thought we were far enough away and uphill that it definitely wasn't going to affect us, and to hear that is was is definitely shocking," she said. "It's concerning to whether our well has got any levels."
Nichols and other neighbors in the area are getting their drinking water tested.
Last September, the first drinking well, down the hill from the burial site, tested positive for the chemical. That family has been drinking bottled water provided by Dartmouth ever since. Their well water continues to exceed state limits acceptable for 1,4-dioxane.
Several local streams have also tested positive for the chemical at levels below the state allotted limit for 1,4-dioxane in groundwater. The chemical was also discovered at a second private property last month, but the landowner does not source their drinking water from the contaminated land.
Later this fall, Dartmouth will be installing a pump and treatment system to try and remove the source of the 1,4-dioxane leftover in the Rennie Farm burial plot.
Dartmouth officials and the contractor in charge of following the chemical plume will be holding open hours at the Rennie Farm burial site in Hanover on the afternoon of Tuesday, October 25th.
UPDATE 8:40a.m. October 13, 2016: This post was updated to include the date of an upcoming public information session held to discuss the contamination remediation.