Hanover
Water regulators already have authorized the work, and so Dartmouth officials said they hoped to start their re-excavation during the week of Aug. 22. The work is anticipated to last only a few days, a spokesperson said, and around the same time the college also will install new monitoring wells to track the flow of a contaminant that entered a neighbor’s water supply.
Dartmouth is still estimating the cost of this latest work, spokeswoman Diana Lawrence said. She previously estimated that the entire project, from a 2011 excavation to today, had cost around $5 million.
“I can’t speculate on the final figure,” she said in an email. “However, Dartmouth is committed to spending whatever is necessary to address the contamination expeditiously and effectively and to protect the health of the neighbors.”
The state officials’ signoff came despite demands from a group of concerned neighbors that the remediation project be dramatically expanded.
In June, college contractors found waste left over from the 2011 excavation, spurring this new round of digging. Residents in the rural area along Hanover Center Road have circulated a petition calling for a more aggressive treatment strategy.
As it stands, Dartmouth will hollow out a 30-by-30-foot area around the burial plot where extra waste turned up in June. For comparison, the neighbors’ requests include that the college dig up the entire acre on which several tons of animal carcasses were buried in the 1960s and ’70s.
But Dartmouth administrators say they are concerned that expanding the work to the full acre could disturb a contaminant that still lingers there.
The 2011 project appears to have to set that chemical, 1,4-dioxane, in motion, which led to the tainting of a well of a neighboring family on Rennie Road.
College officials say they did not want to further disturb the substance before they have a pumping system in place to control its flow. The installation of that system is scheduled for the fall.
Water officials with the New Hampshire Department of Environmental Services last week gave their approval to the college’s more limited plan, saying their priority was to get the known waste out of the ground.
The DES regulators said they would respond to the neighbors’ demands in September, after Dartmouth had collected more data on the site’s groundwater.
A college spokesperson on Thursday said sampling from the new monitoring wells is expected to begin Sept. 5 and yield results on Nov. 11.
The test animals buried at the Rennie Farm came from Dartmouth’s medical school, where they likely were involved in experiments using radioactive isotopes.
Since more carcasses were found in the ground in June, the dump site may contain radioactive materials, and so digging there requires a modification to Dartmouth’s license with the state Radiological Health Section, an office in the Department of Health and Human Services.
That change came on Tuesday with a letter from Twila Kenna, the Radiological Health Section official handling the case. Kenna appeared to have approved the work plan as-is, except for an adjustment to the way waste from the excavation would be stored before shipping.
Messages to Kenna were not returned Thursday.
Rob Wolfe can be reached at rwolfe@vnews.com or at 603-727-3242.