STRAFFORD — The 20-year cleanup of the Elizabeth Mine Superfund site is expected to wrap up this year, though officials at the Environmental Protection Agency say work this summer may lead to some temporary road closures at the site.
At a virtual meeting with Strafford-area residents last week, Ed Hathaway, the EPA’s remedial project manager, said the bridge deck to Tyson Road off Route 132 is being replaced but that the materials shortage in the COVID-19 pandemic has led to a delay in obtaining guardrails.
“All the work should be completed by the end of the month, except for the guardrail. Like many things right now, guardrails are in short supply and we may not be able to have it available until August,” Hathaway said.
In addition, Hathaway said the “major activity right now” is closing an opening to the mine, known as an “adit,” that dates to 1898. Crews are installing a concrete plug that will prevent impounded water in the mine from escaping and forming a sinkhole on Mine Road as it did in 2018. Right now, two potentially unstable “blockages” in the passage are holding back 719,000 gallons of acidic water.
“We’ve closed Copperas Road, as we’ve had to do many other times in the past,” Hathaway said. Mine Road may also be closed so that crews can install the plug safely.
In 2001, the EPA designated the abandoned copper mine a Superfund site. Acid- and metal-contaminated water had leached out of the waste rock and tailings into the streams that feed the west branch of the Ompompanoosuc River since the mine closed in 1958. Contaminated water endangered aquatic life, and unstable tailings threatened nearby homes.
The EPA anticipates the project will cost as much as $96 million, excluding state expenses, EPA officials said. Over the last 20 years, the EPA has installed 60,000 cubic yards of soil to stabilize the tailing dam; diverted shallow groundwater and surface water; replaced approximately 8 acres of toxic wetlands with 15 acres of healthy wetlands that naturally clean the water; and installed a “low permeability cover system” including soil and vegetation that is now home to a 20,000-panel solar array to isolate the mine waste.
Hathaway said the EPA’s monitoring shows that none of the residential wells in the area have any contamination. Groundwater contamination is mostly confined to the waste area. The West Branch of the Ompompanoosuc River and the once-contaminated streams meet water quality standards except for the tributaries of Lord Brook, which is approaching the EPA’s standards. Along with a 10% cost-share of the remediation at the site, the state of Vermont is expected to fund and oversee the long-term maintenance and monitoring of the mine after the EPA completes the cleanup, at a cost of about $61,000 a year, according to Hathaway.
Residents have seen the results of the EPA’s investment in the site. Strafford Selectboard Chairwoman Toni Pippy lived on Mine Road when she first moved to the area and said in an interview on Tuesday that she still remembers the distinct, polluted smell of the abandoned mine.
“If it rained heavily before the EPA came to do their job, the river would turn a deep reddish, coppery color, ” she said. “Now, we never see that.”
Residents this week said that they had a good working relationship with the EPA. The flow of trucks driving to and from the site has slowed to a trickle as the project has wound down. Pippy emphasized that “the EPA folks have been more than responsive to any concerns that the town has had.” Sue Coburn, at South Strafford’s Coburns’ General Store, said she has been “pleasantly surprised about how nice everyone has been.”
But former Selectboard member John Freitag, who has followed the project’s progress since the late 1990s when the EPA first considered cleaning up the site, did say he was concerned about the environmental impact of the cleanup project itself and its high cost. Over 20,000 truck trips have delivered supplies to the site.
“Overall they did a wonderful job and spent a ton of money,” he said. “A real quality job — no question about it. Is it completely practical? I don’t know.”
In the last phase of the project, Hathaway said at the meeting last week, the EPA is focusing on moving from active engineering and “construction-based treatment approaches” to “institutional controls” that will help protect the cleanup.
He said that the EPA will work with residents and local officials to determine what “administrative restraints” work best for the site, and that land-use restrictions are likely within the “waste management area.” The public also will have the opportunity to review and comment on any reclassification of groundwater from the site, though restrictions are expected for areas where there may be contamination, he said.
Because the site remains private property, the mine’s landowners will determine how much public access there will be, with a treatment area and the 27-acre solar array that was installed at the site four years ago will remain fenced in. Last year, trespassers damaged the cap on the South Mine and trespassing vehicles impaired the restored wetlands at the site, the EPA said.
Hathaway said that the EPA will likely transfer control of the site to the state of Vermont within the next two years. Then the state will continue monitoring and taking test samples.
“It’s a fantastic place,” Hathaway, who has been involved with the Elizabeth Mine cleanup for over 20 years, said of Strafford. “I love it up there, but at some point, it’s time for me to go home.”
He said in an email that the EPA will continue working on other contaminated mines in the Upper Valley. The Ely Copper Mine in Vershire has a completed design and is awaiting funding, and the Pike Hill Copper Mine in Corinth is still in the investigation phase, he said.
Claire Potter is a Report for America corps member. She can be reached at cpotter@vnews.com or 603-727-3242.