FALMOUTH -- A military cleanup team is checking for emerging contaminants near two ponds in Mashpee, even as its investigation of those same pollutants continues on Currier Road in Falmouth and near the Otis Rotary in Pocasset.
A total of nine homes are now being supplied with bottled water -- six in Falmouth and three in Bourne -- because perfluorinated compounds (PFCs) found in well water exceeds federal advisory levels. There were originally seven homes being supplied with bottled water because of the contamination.
In May, the Environmental Protection Agency changed its advisory level for PFCs, which include PFOS and PFOA, from 0.2 micrograms per liter and 0.4 micrograms per liter to 0.07 micrograms per liter for both. The agency also advised that if both are present, they should be combined as a risk. At the time, based on the change, the samples at four houses were at levels above those recommended by EPA.
"They came up with a new number that is protective," said Jane Downing, an EPA official. Pregnant and lactating women are considered most at risk if exposed to PFCs, based on animal studies, she said.
The Air Force Civil Engineer Center has since added Johns Pond and Ashument Pond to its testing and found levels of PFCs above the drinking water advisory. Levels ranged from 0.078 to 0.18 micrograms per liter for the two compounds in both ponds.
The ponds were tested because elevated levels were found nearby on Joint Base Cape Cod and just outside the base boundary where a firefighter training site was once located, said Rose Forbes, remediation director for the Air Force. PFCs are a chemical used in firefighting foam and may be the source of the contamination, she said.
About a dozen homeowners attended an informational session Wednesday night with the Air Force and environmental regulators at the Unitarian Universalist Church in East Falmouth. Several expressed frustration at the slow pace of getting approved for water filtration systems and concern over the changing results.
"I'd like to see them put in town water, it's a really small link," said Susan Houghton, who owns an affected rental property. "It's really a guessing story. You have to wait to get the samples done. Meanwhile, young people are risk."
Donald McCarthy owns one of the houses that tested above the federal advisory in May and had another that was just below. This time, both are above the health advisory.
"We knew it was only a matter of time," he said.
McCarthy is pushing for water filtration systems for both houses and said he is frustrated by the pace after Forbes said it would take another four to six months to secure government funding for the systems.
McCarthy's neighbor James Hocking has seen levels in test results creep up, but not enough to warrant a bottled water delivery paid for by the Air Force. Hocking has lived in the neighborhood long enough to remember when discussions about groundwater contamination were at a fever pitch on the base and wondered aloud why Currier Road was passed by at that time.
"I think it was bad planning, bad decisions and I'm on the wrong end of these bad plans and bad decisions," he said.
The Air Force has been testing private wells in the neighborhood for about a year since 1,4 dioxane, another emerging contaminant, was found in water being discharged from one of its treatment plants into a trench. As a precaution, the military has stopped using that trench to return water back into the environment.
The Air Force is still doing outreach in a neighborhood near Johns Pond in Mashpee. While most of the neighborhood is on a public drinking-water supply, there are some private wells, said Douglas Karson, a community outreach coordinator for the cleanup program. Karson is hoping to identify them and set them up for quarterly testing, he said.
Anyone who has a private drinking-water well in that area can contact Karson for testing at 508-968-4678, extension 2, or by email at email@example.com.
Marc Nascarella, director of environmental toxicology programs for the state Department of Public Health, said the ponds are safe for "incidental exposure" like boating and swimming, but are already off limits for consuming fish because of high mercury levels.
Fish have not been tested for PFCs, though Forbes said that's something that's being considered.