Hanover — New Hampshire water regulators on Thursday approved Dartmouth College’s revised cleanup plan for the Rennie Farm, a laboratory dump site that contaminated a private well.
Last month, workers discovered waste that was missed during a 2011 excavation, spurring this new work.
The project, however, will not go forward until state nuclear regulators weigh in. Those officials, who have authority over the radiological materials presumed to be in the site, said their response is coming next week.
The approval from the state Department of Environmental Services, which has jurisdiction over water contamination, brings the college a small step closer to completing a costly project that began five years ago. A spokeswoman recently estimated that Dartmouth had spent $5 million so far to remediate the hillside where nearly 50 years ago the medical school dumped several tons of radioactive test animals.
College spokespeople could not be reached for comment Friday.
The water regulators also postponed a response to demands from neighbors that the work be dramatically expanded. Paul Rydel, the DES official handling the case, said the immediate goal was to remove extra lab animals found last month.
“They’re poised and ready to do that,” he said of Dartmouth. “It just makes sense to have them go and do that as soon as possible.”
A group of 36 neighbors last month circulated a petition sharply criticizing the college and demanding a more aggressive cleanup, including a full excavation of the one-acre burial site, which lies on a 218-acre, mostly wooded property above Hanover Center Road.
Dartmouth’s work plan, submitted July 25, calls for a narrower scope: the excavation of a roughly 30-by-30-foot area around one burial plot presumed to contain extra waste.
In an interview Friday afternoon, Rydel said there would be an opportunity to address the neighbors’ request later. The college is due to submit a “much more comprehensive” report in September, he said, which will include more detailed groundwater data that will inform the state’s response to residents.
It was in preparing this report that Dartmouth’s environmental contractors last month found bags of animals remains that the 2011 excavators had missed, Rydel said.
That discovery triggered the re-excavation of a site declared free of radioactivity years ago. State nuclear regulators in 2013 had released the dumping ground from the license that Dartmouth holds for radioactive materials, and so the college’s July 25 work plan requested that the new digging be incorporated into its current permit.
Twila Kenna, manager of the state Radiological Health Section office that supervised the Rennie Farm, said this week had officials known of the extra material, they would not have discontinued the license.
“With the information now that there’s material there, the release would not be given,” Kenna said in a voice message on Thursday.
Back in 2011, when Dartmouth excavated the radioactive carcasses, its contractors noted that they had had difficulty digging up one of the burial plots, and said waste likely remained there.
Nevertheless, the contractors said the amount of hazardous material probably was negligible, and deemed the work complete.
In July, workers found more bags of animals in the same burial plot.
“The current work plan is under review,” Kenna added in her Thursday message, “and should be finished either today or tomorrow, and hopefully that will improve conditions greatly.”
The following day, Kenna estimated her office would respond to Dartmouth’s plan early next week.Rob Wolfe can be reached at firstname.lastname@example.org or at 603-727-3242.