Originally published in The Weekly Packet, July 31, 2014
Callahan Mine update
First phase of mine cleanup completed
by Rich Hewitt
The first phase of the cleanup at the Callahan Mine Superfund site has been completed, but the largest and most expensive part of the project is still to come.
Meanwhile, concerns linger over the health hazards posed by contaminants at the former mine site and the legal hazards attached to the 150-acre site.
Work on the first phase of the cleanup was completed in 2013, according to Ed Hathaway, the EPA project manager for the cleanup. Hathaway provided the annual update on the project on Tuesday, July 29, before a small group of local and seasonal residents.
The initial phase of the cleanup included the excavation of more than 49,000 cubic yards of contaminated materials from the mine site. About 12,000 cubic yards of that material that contained high concentrations of PCBs were taken to either a hazardous waste landfill or special waste landfill. The rest, including soils with low concentrations of PCBs and soils on adjacent residential properties contaminated with lead and arsenic, was placed on the tailings impoundment on site. That area will be covered in the next phase of the cleanup.
According to Hathaway, the Maine Department of Transportation, working with the state’s DEP and the EPA, is developing a design for that cover. The design, which includes a dewatering mechanism, should be completed by next spring, he said.
That next phase also includes the largest part of the cleanup, which also will be the most expensive.
To date, the cleanup has cost $7 million. That’s three and a half times the original estimate for the first phase, Hathaway said. He noted, however, that both the amount of contamination and the contaminated areas at the site had increased significantly more than that.
In response to questions about why the initial assessments were so far off, Hathaway said that the Callahan site was unusual. PCB contamination, he said, is usually localized. At Callahan, the PCB contamination likely came from transformers used on the site.
“With PCBs, they’re usually focused where the spill is,” he said. “We looked at the area and we had clean strips surround the area [where the transformers were].”
He said, however, that the EPA had a longtime veteran who, literally, could smell PCBs, inspect the site.
“He checked the site and said ‘you need to sample here, you need to sample there,’ and everywhere he pointed, he was right,” Hathaway said. “It was as if someone had pushed [the PCBs] around and spread it all over the place. I haven’t seen a pattern like that before. It was as if they wanted to contaminate as large an area as possible.”
The next phase of the cleanup could cost as much as $25 million, Hathaway said.
“We’ve estimated that there’s about 300,000 cubic yards of contaminated rock and about 100,000 cubic yards of contaminated sediment,” he said. “The remaining work will cost in the $20 million to $25 million range.”
Hathaway said he had no timeline for when the remaining work would be done. The design work for the rock and sediment cleanup has been delayed while the MDOT waits for funding for that part of the project.
Once the design is ready, Hathaway said, the project goes onto a national priority list where it competes for funding with other Superfund projects around the country. Funding for those projects is based on appropriations from Congress.
The EPA also has postponed designing a cleanup of contaminated groundwater at the mine site. Hathaway explained that they want to see what effect the other cleanup measures have on that groundwater before taking any cleanup action.
“We’re going to wait until after the cleanup,” he said. “It’s possible that the groundwater will clean itself up.”
Residents raised concerns about any ongoing health hazards at the site. State Rep. Ralph Chapman (D-Brooksville) asked specifically if the EPA was reassessing its cleanup plans in light of new scientific studies from Dartmouth University and the U.S. Geological Service. Both studies indicate that contamination from the mine site continues to affect Goose Pond and the surrounding estuary and that the contamination is bioaccumulating—or building up—in animals such as shell fish and fish in the area. The Dartmouth study in particular notes that there are indications that the contamination in animals is moving up the food chain and that it could move out of Goose Pond as larger animals move in and out of the pond.
Hathaway said the new studies matched information the EPA had developed on the site, adding the agency has not amended its cleanup plan. He indicated that if that plan is successful, it will eliminate the contamination leaching into the pond and the contamination accumulating in animals.
Residents, including the town’s selectmen, raised concern about future liability at the site once the cleanup has been completed. During the cleanup, the EPA, DEP and MDOT are working together with the DOT responsible for developing the cleanup plans. Once the cleanup is completed, Hathaway said, the responsibility for ongoing maintenance of the site will remain with the state. That will be true if the site remains with its current owner or if the property is transferred to a new owner, he said.
The EPA has the responsibility under current law to continue to inspect the site on a five-year review cycle.
That will continue “forever,” he said, unless Congress changes the law. If any new contamination was discovered, as long as the owners did not cause it, it would be the responsibility of state.