EPA, Air Force Dispute Cleanup
FALMOUTH, Mass. To treat or not to treat. That is the question.
Air Force officials have proposed allowing a portion of the so-called Ashumet Valley groundwater contamination plume to continue to dissipate until it dilutes below levels that are considered harmful to humans.
The move would save taxpayers about $17 million and still protect the community, Air Force officials argue.
But U.S. Environmental Protection Agency officials say environmental laws favor an active cleanup -- such as a treatment system that would capture the toe of the plume and clean an additional 239 pounds of contamination.
Air Force, EPA and state Department of Environmental Protection Officials will meet today to seek common ground.
Meanwhile, community members who have long advised the Air Force and EPA about the cleanup said they must carefully weigh the costs and benefits to Falmouth and its residents before they decide which option would be best.
"It's a balancing act there," said Steven Hurley, a member of the citizens team that advises the Air Force on the cleanup.
"You have to balance whether the risk of contamination from pollution is worth the physical impacts to the environment and the physical impacts to the people in the neighborhood."
The Ashumet Valley plume emanates from a former firefighter training site and wastewater plant at Otis Air National Guard Base into the northeast corner of Falmouth.
Unsafe for drinking
The plume contains perchloroethene and trichloroethene, which are found in solvents, as high as approximately 50 parts per billion.
The federal safe drinking water standard for both contaminants is 5 parts per billion, or 2.5 teaspoons of water in an Olympic-sized swimming pool.
The aquifer under the base is the primary source of drinking water for the Upper Cape.
The Air Force has spent more than $40 million since 1997 to investigate and remove the contamination.
There is already a groundwater treatment system cleaning the northernmost portion of the plume.
But Air Force officials have proposed allowing the southern portion of the plume to go untreated.
The contaminants would eventually dissipate until they meet safety standards, according to the Air Force.
"That is the status quo," said Lynne Jennings, EPA's manager for the Otis cleanup.
"We are saying you need treatment on the lower half of this plume."
EPA officials want the Air Force to build a new treatment plant or add another well to the current pump-and-treat system -- a move Jennings said would treat a significant mass of contamination that would otherwise bubble up in Backus River cranberry bogs.
"There is a large mass that still has to make its way to the bogs," Jennings said.
Air Force officials argue the contamination does not pose a threat to public health because Falmouth does not intend to draw drinking water from the affected area and local residents have been connected to the town's municipal water system.
Considering it would cost an estimated $17 million to build and operate a new treatment plant, allowing the plume to naturally dissipate makes sense, according to Air Force cleanup manager Jon Davis.
The plume will dilute to less than 10 parts per billion in about 12 years, according to Air Force models.
"It is not a portion of the aquifer that is going to be used for water supply," Davis said.
Differences between the Air Force and environmental regulators will likely surface at the next Air Force cleanup citizen meeting next month.
Source: McClatchy-Tribune Information Services