Dartmouth College Says Toxicity Levels Greatly Reduced at Rennie Farm

Valley News Staff Writer
Published: 7/24/2018 11:47:51 PM
Modified: 7/25/2018 11:05:30 AM

Hanover — Dartmouth College is reporting significant progress in cleaning up the chemical solvent that was fouling water wells near a former laboratory waste site on its Rennie Farm property.

“Current testing shows there are really significant reductions in 1,4-dioxane,” Ellen Arnold, associate general counsel with Dartmouth, said on Tuesday, referencing the chemical that was found to be migrating from the college dump site down to the well of a neighboring family. “We have seen a 46 percent reduction at the source area on-site, and a 64 percent reduction” in the Rennie Farm areas to which the contaminant had spread.

Meanwhile, the New Hampshire Department of Environmental Services has insisted, over Dartmouth’s objections, that the college test the water for PFAS, a set of chemical contaminants that have been linked to impaired childhood development, reduced pregnancy rates and cancer.

“PFAS are new in the sense that their potential health effects are only recently recognized,” the state DES Hazardous Waste Management Bureau’s Paul Rydel said on Tuesday. “The compounds themselves, which are ingredients in Teflon and stain-resistant material, have been in consumer products for a long time.”

Rydel rejected an argument, submitted to the state earlier this year by a Dartmouth consultant, that testing for PFAS should not be required.

“The potential presence (or absence) of PFAS as a site-related contaminant can only be assessed via targeted groundwater sampling ... and thus we continue to require that Dartmouth complete an initial groundwater screening for PFAS,” Rydel wrote in a June 19 letter to Dartmouth.

Since the 1940s, chemical manufacturing companies like 3M and DuPont have sold PFAS for use in products ranging from pizza boxes to fire-fighting foams; over the past 10 years or so, the Environmental Protection Agency has worked with the industry to phase out most PFAS from national production chains, though they remain present in many imported products.

Beginning in 2016, there have been several high-profile cases, including in New York, Vermont and New Hampshire, in which public drinking water was found to be contaminated by PFOA and PFOS (two of the PFAS compounds that have been the subject of health advisories from the EPA).

With regulatory agencies still working through the tangled relationship between individual PFAS compounds, concentration levels, and health impacts, the DES told Dartmouth earlier this year that all active hazardous waste sites, including Rennie Farm, should be tested for PFAS.

Dartmouth’s consultant, GZA GeoEnvironmental Inc., argued against the testing because, it said, none of the documentation at the Hanover Center site, where thousands of animals used in lab experiments were buried several decades ago, hinted at any PFAS or PFAS-related products being present.

But in Rydel’s response, he found that “due to their properties to resist heat, oils, and water, PFAS are widely known to have been used in the formulation of many laboratory and common products,” including non-stick products, and clot-resistant coatings on needles, seals and gaskets on medical equipment.

Arnold said on Tuesday that the college plans to comply.

“We’re going to do the sampling,” she said. “We’re planning it in our September sampling round.”

She said she thought the added costs of such testing would likely be marginal, given that the wells have been dug and already are being tested for 1,4-dioxane.

The college spent roughly $10 million on cleanup costs at the Rennie Farm in fiscal years 2016 and 2017, and budgeted an additional $22 million for future costs. Arnold said that even a positive test for PFAS might be less problematic for the remediation effort than one might assume.

“As I’m sure you would imagine, we have thought about that, and the irony is that one of the most effective treatments for PFAS is carbon filter treatment which is what we already have there,” Arnold said. “We think we would be able to treat it effectively.”

She said that treatment system, which sucks water out of a series of wells, filters it, and returns it to the aquifer, seems to be doing the job for the 1,4-dioxane, which was found to exist in an underground plume in 2015.

“All of our monitoring shows there has been no expansion of the plume. That’s working well,” Arnold said, referencing the 2017 annual report on the site released in March. “The good news is that the water is being cleaned and the treatment is effective and we know the contamination is not spreading. We feel like we have a good handle on the area.”

Matt Hongoltz-Hetling can be reached at mhonghet@vnews.com or 603-727-3211.

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