PARIS – The Environmental Protection Agency will clean up toxic sludge left behind at the old A.C. Lawrence tannery after it determines the extent of soil contamination at the site.
The tannery, which closed in 1985, was not in violation of any state laws regarding the sludge sites.
The Superfund cleanup could begin next month and continue into July and cost up to $1 million. That’s an early and high estimate based on a rough idea of the depth and reach of the underground sludge, according to the EPA.
“We have counted 11 lagoons, and we’re going to try to determine their size,” said Wayne Paradis, project manager with the Maine Department of Environmental Protection. “We have drawings and aerial photographs, but we need to get our boots on the ground and determine what is physically in the ground.”
This Friday, Maine DEP will use ground penetrating radar on the site to delineate the lagoons. Maine is contributing up to $10,000 toward the survey cost as well as clearing brush in the area. The rest of the project will be funded through the EPA.
Amy Jean Lussier, on-site coordinator with the EPA, said by phone Wednesday she will conduct soil borings beginning May 15 at the seven-acre site on Oxford Street to determine the depth of contamination. Based on that data, she will be better able to judge the cost of the cleanup, which will entail excavating the sludge and disposing of it in landfills.
Paradis said a 2003 sampling showed that the sludge layer was between 1 and 2 feet below ground, and on average 3-feet thick.
For more than 20 years – up until 1973 or 1974 – the tannery used the lagoons to filter wastes generated from processing and dyeing hides. The waste matter was pumped from the factory across the Little Androscoggin River to the lagoons, where the solids would settle out and the residual liquids would percolate through the mud.
When one lagoon was filled, the tannery created another one, Lussier said.
The A.C. Lawrence Leather Co. shut down in 1985. According to the EPA, the sludge beds were closed and capped then, with the majority of sludge remaining in place. Although the solids should have been removed, officials said they remain at the site.
The EPA has also detected chromium contamination in the soil along the riverbank and in river sediments.
“Where the site is sitting is in a groundwater aquifer,” Lussier said. “There is no well drawing from it now, but there could be. It’s a contact threat and there’s contamination along the river, and people use that for fishing and kayaking.”
While the biggest concern is chromium, which was used to dye the hides, there are also some solvent residuals, which were used to remove the fat from the hides, as well as a little bit of lead, she said.