BROOKSVILLE, Maine — State and federal environmental agencies will hold a meeting next week in Brooksville to update residents about ongoing cleanup efforts at the toxic former Callahan Mine site in Cape Rosier.
The meeting, hosted by U.S. Environmental Protection Agency and Maine Department of Environmental Protection, will take place at 7 p.m. Wednesday, Oct. 24, at the Brooksville Public Service Building.
The site, where 800,000 tons of rock bearing zinc and copper ore were mined from 1968 to 1972, was listed as a “Superfund” site in 2002. The designation is reserved for abandoned hazardous waste sites deemed a national priority by the EPA. Maine is home to 15 similar “long term/national priority” sites, including the former air stations in Brunswick and Limestone.
An EPA assessment of the Callahan Mine found the site had several threats to human health and the environment, mostly due to the chemical processes used in mining the zinc and copper ore.
A three-phase cleanup program at the site began in Spring 2011 with the removal of soil contaminated with polychlorinated biphenyls — PCBs — and the cleanup of arsenic and lead contamination in the soil of private properties near the site. That work is mostly complete, according to EPA reports.
But the cleanup effort also calls for much of the contaminated materials — at the ore pad, the mine operations area and one of the waste rock piles — as well as contaminated sediment to be disposed of in the 320-feet deep former mine pit, which was flooded when operations ceased in 1972 and is now underwater.
It also calls for an impermeable cap to be installed over the tailings impoundment, where leftover material from the ore separation process was dumped.
Responding to questions from residents in 2009 about whether contaminated material dumped into the pit would seep into nearby Goose Pond or otherwise, EPA Project Manager Ed Hathaway said there were methods available to prevent the dispersal of contaminants.
Hathaway also said the cleanup cost could total about $23 million. The state will have to pay 10 percent of whatever price the cleanup effort carries.
Efforts Friday to contact Hathaway and EPA Community Involvement Coordinator Pam Harting-Barrat for information about the meeting, or for an update on the cleanup effort, were unsuccessful.
The Callahan Mine also will serve as a cautionary tale at a presentation by the National Resources Council of Maine and the Marine Environmental Research Institute scheduled for 6:30 p.m. Tuesday, Oct. 30, at MERI’s Blue Hill facility.
National Resources Council of Maine scientist Nick Bennett claims a law signed by Gov. Paul LePage in May could threaten Maine’s water supply and wildlife, and points to the effect of just four years of mining at Callahan as a prime example.
The law puts into motion an overhaul of two-decades-old state mining regulations that will not be complete until 2014. And then, the rules must get the blessing of the Legislature. But National Resources Council of Maine and other environmental groups have said the new law will weaken groundwater protection standards and cleanup requirements for mining operations.
For information on the EPA and Maine DEP meeting, email Harting-Barrat at email@example.com. For information on the presentation at MERI, call Todd Martin at 430-0115.
Follow Mario Moretto on Twitter at @riocarmine.