Some fly ash will remain in Wenham LakePublished by MAC on 2003-11-14
Some fly ash will remain in Wenham Lake
The Salem News, by Marc Fortier, Staff writer
Friday, November 14, 2003
Beverly - After four years of wrangling, the parties involved in the cleanup of Wenham Lake agreed on a course of action yesterday that calls for the removal of 4,000 to 6,000 cubic yards of fly ash from the bottom of the regional drinking water supply.
Initial plans had called for all 7,800 cubic yards of fly ash in the lake to be removed, but that plan was scrapped when the Salem and Beverly Water Supply Board, which controls the drinking water for the two cities, expressed concern that dredging might stir up the ash, releasing arsenic into the water.
Capping the fly ash at the bottom of the lake was also seen as too risky, as it would only last 10 years and the technology hasn't been tested.
The level of arsenic being released into the lake by the fly ash is below federal and state drinking water standards, so engineers recommended removing only 70 percent of the material. Most of that work can be done without going into the water, during the driest period of the year in September and October.
"We basically have to take what nature gives us as far as the water level," said Mark Mahoney, an engineer hired by New England Power to work on the project.
As the former owner of the Salem power plant, New England Power has agreed to pay for the removal of the fly ash, a byproduct of coal burning. The ash was buried at the Vitale dump in the 1950s and 1960s, and over the years it migrated to the lake, leaving deposits of ash that are more than 3 feet deep in some places at the bottom of the reservoir.
The engineers feel the ash left in the lake will be relatively safe with the removal of the majority of it and through cutting off the source of the material by capping the Vitale dump and cleaning up Airport Brook. The power company agreed to develop a 50-year monitoring program to make sure the arsenic levels don't increase.
"The key is eliminating the source," said Michael Lotti, project manager for New England Power. "When you cut the supply off, over time it's just going to get better."
There are potential problems with the proposed course of action. If next year is particularly wet, the water level in the lake will be too high and much of the fly ash in the lake will be have to be left in place.
"If you get a wet year, you're really not going to get much bang for your buck," Conservation Commission Chairman David Lang observed.
But Mahoney said even if the water level doesn't drop significantly, 50 to 60 percent of the fly ash could still be taken out. He said New England Power will work with the water board to see if the water can be kept lower than normal while the work is being done.
Lori Ehrlich of the Wenham Lake Watershed Association, a group that fought for the lake cleanup, expressed skepticism about the latest proposal, especially its dependence on the weather.
"It feels a little theoretical to me right now," she said. "It's hard to evaluate if it's good news or bad news because there's so much at the whim of Mother Nature."
Despite its concerns, members of the Wenham Lake Technical Advisory Committee -- the group of public officials, activists and interested observers that has been overseeing the lake cleanup -- endorsed New England Power's cleanup plan.
"There's going to be a divergence of opinions," said attorney Jan Schlichtmann, president of the Wenham Lake Watershed Association. "Essentially, what they have offered us is the best in an imperfect world. We should give it our full support."
Now that a plan of action has been settled, New England Power will work on getting the needed permits with the hope that it can start work in the spring. Work would start on the upland portion of the project, cleaning up and capping the Vitale site and Airport Brook, before getting to the lake itself.
Lotti said it will take a "Herculean effort" to get all of the permits in time to start work next year. If the project hits any snags, he said, the cleanup might not start until 2005.
He said another Wenham Lake Technical Advisory Committee meeting will be held in early January to update everyone on the permitting process and discuss the long-term monitoring plan.