BROOKSVILLE, Maine — Could high concentrations of copper at the Callahan mine site have changed the DNA of fish in the adjacent waters of Goose Cove?
That is just one of the questions a team of scientists from the Mount Desert Island Biological Laboratory in Bar Harbor hopes to answer as part of a study in the cove. Copper concentrations at the mine site, according to Charles Wray, a staff scientist at the MDI lab, are the highest anywhere in New England. The study will focus on the effects of the metal, which has been leaching into the cove, on the fish.
Although the study will concentrate on fish in Goose Cove, known locally as killifish, Wray said the findings could provide valuable information about the effect of toxic metals on humans.
“We have an opportunity to understand how copper is interacting on a whole population, and we’ll be able to transfer that information on how copper toxicity interacts in humans,” Wray said.
The Callahan Mining Co. did extensive mining at the site in the late 1960s and early 1970s, extracting an estimated 800,000 tons of rock containing copper, zinc, lead and traces of silver from the open pit site. About 5 million tons of waste rock containing contaminants also was removed from the mine and deposited on the site.
Since that time, those contaminants have leached from the site and in 2002 it was listed by the U.S. Environmental Protection Agency as a SuperFund site. Earlier this year, the EPA adopted a cleanup plan for the site and plans to begin one phase of the cleanup next spring.
“This study will give us an opportunity to understand how well a vertebrate population tolerates metal stress,” Wray said. “And we will be able to monitor the success of the cleanup.”
The researchers were on the site this summer and gathered baseline information about the environment.
“We’ve got here right at the right moment,” he said. “It would have been good to study the site in 1965 [before the mining operations started], but that’s not going to happen. But here we’ll be able to study the site pre-cleanup, during the cleanup and after the cleanup.”
The study involves both staff and visiting scientists to the MDI lab, including researchers from College of the Atlantic, Dartmouth College and Indiana University. It is being conducted under the Dartmouth College SuperFund program, which has conducted studies at other SuperFund sites, funded through grants from the National Institute of Environmental Health Sciences.
The project actually involves several different studies by the different scientists involved. The team was at the Goose Cove estuary near the mine site this summer collecting fish samples for research.
Celia Chen from Dartmouth is working to determine how copper bioaccumulates in the fish and to measure how much copper is accumulating in them.
Joseph Shaw at Indiana is trying to determine how the killifish have reacted to the copper and whether there have been any genetic changes because of its presence.
“We’re not sure what’s happening at the site,” Wray said.
Wray and Chris Petersen from COA, are looking at the overall populations of killifish in Goose Cove and other nearby sites to determine if the killifish in the cove are a distinct species.
Bruce Stanton, also from Dartmouth, is working on the molecular level looking at how the metal interacts with proteins in molecules.
Wray said the researchers will compare their findings with the results from other SuperFund sites that have been studied through the Dartmouth program. One of the benefits of beginning the study now is that researchers can monitor the fish population throughout the SuperFund cleanup process.
The scientists reviewed the project at a meeting with community members this summer and likely will make future reports to residents, the EPA and the current owner of the property.
“There are a lot of people interested in this site,” Wray said. “And they have been involved in this project right from the get-go. And that’s good. We’re not isolated in the lab. That’s a good thing for science.”
The researchers expect to return to the site next summer, by which time, the initial cleanup of a portion of the site should be under way.