Published DateGILFORD — A plan to remove virtually all the toxic coal tar dumped and buried on land along Lower Liberty Hill Road by 2015 was outlined by state environmental officials and an environmental engineer at a meeting attended by town officials and members of the public Wednesday evening.
An estimated 99.8 percent of the contaminated soil currently beneath four house lots will be removed over the period of two years under the plan now being considered, according to John Ash, vice president of GEI Consultants Inc., a Massachusetts-based geotechnical consulting firm. GEI has been retained by Liberty Utilities which now owns the properties at 69, 77, 83 and 87 Liberty Hill Road, and is the latest corporate successor to the gas utility responsible for the dumping of the coal tar in 1952 in what was then a sand and gravel pit. Ash said he expects 45,000 cubic yards of tainted soil will need to be removed in the multimillion-dollar clean-up.
He said the actual removal is expected to begin in the spring or summer of 2014 and would take two construction seasons to complete. No work will take place at the site during the winter of 2014-15, he explained.
Michael McCluskey, an engineer with the state Department of Environmental Services' Waste Management Division, said DES's goal is to remove the contaminated soil "to the greatest extent practicable."
"We are talking about moving ahead with something that will be of benefit to the community," he told the audience of about 30 people.
Mary Casey, environmental program manager for Liberty Utilities, said it was still too early to project exactly how much the clean-up would cost the utility. But she noted that a few years ago some were estimating the cost could reach about $13 million.
Ash said the first phase of the three-year project should begin in March when 50 additional test borings will be drilled around the supine figure-eight-shaped site in order to give scientists and engineers more precise data on the location and concentration of the coal tar deposits. Once the results of the test borings have been analysed, permits will be applied for some time during the summer. Barring any problems in the permitting process, work to select contractors to do the work will take place next winter. A pre-construction public meeting will take place during that time and the actual removal work will being in the spring of 2014.
"This project is not that simple," Ash said. He expected that heavy excavation equipment will need to dig as deep at 55 feet in some spots to get to some of the coal tar deposits. Removing 45,000 cubic yards of material will entail several thousand dump truck loads and Ash predicted that because of all the truck traffic Lower Liberty Hill Road "will take a beating."
John Regan, supervisor of hazardous waste remediation for DES, said the project is one of the largest to be undertaken in the state.
Ever since the buried contamination was discovered in 2005 the Board of Selectmen has insisted on the removal of 100-percent of the coal tar. But Ash said that to accomplish that would require removing an additional 36,000 cubic yards of soil from the site. "That would involve (removing) a big volume of soil to remove a small amount of contaminant," he said.
However, Dan Morrissey, an engineering consultant being retained by the town, said that leaving any amount of contaminated soil in the ground raises concerns about possibility of pollutants getting into nearby Jewett Brook in the future. Morrissey also said that the town should have its own representative on site during the removal process.
Reiterating that point, attorney Tupper Kinder, who is representing the town on the Liberty Hill clean-up, said, "The selectmen want an independent third party monitoring that the project is handled properly and thoroughly."
McCluskey said that DES would be responsive to the town's concerns.
Kathy Lacroix, who lives at 98 Liberty Hill Road, diagonally across the road from the contaminated properties, said she was pleased with much of the clean-up plan, including steps that would be taken to minimize dust and odor from site. But she was worried that pollution would have long-term harm on property values in the area, making it difficult for existing residents to sell their homes and making banks reluctant to underwrite mortgages for potential buyers.
Town Administrator Scott Dunn said that selectmen realize that property values in the area have been hard hit because of the contamination and as a result the have selectmen been insisting on a full clean-up. "Selectmen want the neighborhood to come back and the stigma removed. But it's a slow process," he said. He added that the town intends to meet with officials from Liberty Utilities about future uses for the properties that will be cleaned up – "something that will contribute to the values of the neighborhood."