HANOVER — Dartmouth College has secured an easement from a landowner near Rennie Farm to treat contaminated groundwater that has migrated from the former college laboratory dump site, a step the college says will expedite the overall cleanup. Dartmouth is working to obtain state and local permits to install wells that will extract groundwater and pump it underneath Rennie Road to its existing treatment system at the former dump site, college officials said on Thursday.
The 15-year easement is intended to help accelerate the cleanup of the spread of the chemical 1,4 dioxane, which was found in soil and groundwater both on Rennie Farm and on private property across Rennie Road.
The rural site had been used as a dumping ground in the 1960s and 1970s for the carcasses of test animals used at what was then known as Dartmouth Medical School. Dartmouth excavated most of the waste in 2011, but dioxane was later found in a private well along Rennie Road.
Ellen Arnold, the Dartmouth lawyer who has been helping to oversee the cleanup, said the work will help speed up the removal of dioxane from the area.
“We’ve had excellent results from the existing system. There has been no expansion of the contamination,” she said.
Jim Wieck, a consultant with GZA Geo Environmental Inc., the contractor that is handling the cleanup, said state officials had not required Dartmouth to expand the cleanup.
“This is a voluntary thing Dartmouth is doing,” Wieck said.
Last July, the College reported significant progress in the cleanup.
The concentration of 1,4 dioxane has been reduced by 46 percent on-site and by 64 percent downgradient of the site, according to Dartmouth.
Arnold said Dartmouth hopes to have the new groundwater extraction system, which could include 15 new wells, up and running in six to eight months.
The existing treatment system consists of 12 extraction wells and over 90 monitoring wells.
The easement has been obtained from William Braman, who owns a 144-acre parcel off Hanover Center Road that also runs along Rennie Road just north of the Higgins home where dioxane was found in a drinking well. Arnold said the easement covers about 11 acres of land, and that it was where Dartmouth has previously reported that dioxane had been detected.
“I’m just glad we’re cleaning it up and getting this problem resolved as fast as possible for the neighbors,” said Braman. His home, which has been in his family for three generations, is near Hanover Center Road, and his drinking water supply is safe for consumption.
Braman was compensated $65,000 for property damage and $15,000 a year for the easement, according to an internal Dartmouth document obtained by the Valley News.
The Dartmouth document also said the groundwater pump system would control the “migration of contamination,” accelerate the remediation of dioxane, limit its presence in surface water and “increases community confidence.”
Dartmouth also has spent $4.2 million to purchase six homes and two large, vacant parcels since 2017 under what it calls a “value assurance program” for nearby landowners in Hanover Center.
Arnold said the college is currently working with a local real estate agent to determine which properties Dartmouth now owns should be resold.
Following state-mandated testing of all groundwater management sites, Dartmouth also tested last year for PFAS, chemicals which have been linked to cancer and other health problems, and which have been implicated in contamination elsewhere in New Hampshire.
The testing determined that PFAS is not a contaminant of concern at the site, Arnold said. Among the nine PFAS compounds tested, only one was detected to be above reporting limits of 2.08 nanograms per liter, coming in at 2.1 nanograms per liter. Dartmouth officials said state officials are not requiring any further sampling or action.
Arnold also added that as of last March, sampling revealed that there is no longer any more radiological waste from animal carcasses at the site.
But the cleanup has not satisfied all of Rennie Farm’s neighbors.
Duncan Syme, whose house is on Rennie Road but is not eligible for the value assurance program, expressed frustration at the college’s lack of generosity in compensation and response to the contamination, which he said had been known about for years.
“Dartmouth has not behaved like a good neighbor — exactly the opposite. They’ve taken an adversarial role at every step,” Syme asserted.
He also said the college hasn’t communicated well about the future of the homes, some now empty, that it has purchased because of concerns over contamination.
“It just seems like a shame to let these properties and these neighborhoods become more and more vacant,” he said.
Amanda Zhou can be reached at azhou@vnews.com.