CONCORD, N.H. >> New Hampshire says emissions of a chemical used to make Teflon coatings may be the source behind the contamination of more than 40 wells in several towns.
The company behind those emissions, Saint-Gobain Performance Plastics, has said it's too early to say whether it's responsible for contaminating wells in Merrimack, Litchfield and Manchester.
So far, the state has determined that 33 wells in Litchfield, seven in Merrimack and one in Manchester contain high levels of the chemical PFOA, suspected by some scientists to be a carcinogen. Some concentrations were four times higher than the levels considered safe by the Environmental Protection Agency.
The state recently told Saint-Gobain it believes the company was "potentially responsible" for the contamination but isn't sure whether the chemicals were dumped into the water or spread through the air.
Mike Fitzgerald, an assistant director with the state Environmental Services Department, said it's possible the chemical spread through the air since the company emitted a derivative of PFOA for several years, starting in 2001, before reducing emissions it to almost zero. The derivative becomes PFOA once it is dissolved in water.
"We do know they emitted to the air and that it can attach itself to particles in the air and then be deposited on the ground," he said. "When it rains, it can percolate down into the ground and carry the compound down into groundwater. Given the widespread nature of contamination, that certainly makes some sense to us that air dispersion could be one of the pathways."
The company, which bought the Merrimack plant from ChemFAB in 2000, initially believed it wasn't emitting anything harmful. But Fitzgerald said that changed in 2004 after the company installed more sophisticated technology and realized it was emitting the chemical. After the company alerted the state, DES determined Saint Gobain was exceeding state air limits for the chemical, and the company agreed to significantly reduce emissions.
But the state didn't move to do any groundwater testing until this year because there was no indication at the time that the emissions posed a threat to groundwater, Fitzgerald said. That only came to light this year after wells near Saint-Gobain facilities in Hoosick Falls, New York, were found to be contaminated with PFOA. More than 100 wells in Bennington and North Bennington, Vermont, also have since been found contaminated with PFOA around the company's now-closed plant.
"Looking back, there is nothing we would have done differently," Fitzgerald said.
"Certainly we would have preferred to know this was a potential problem from a groundwater perspective," he said.
Now that the DES is aware of the connection, Fitzgerald said the state has started examining several facilities that may have used the chemical to determine whether PFOA contamination is more widespread. Vermont is doing something similar, with Gov. Peter Shumlin saying testing will be done near 11 industrial sites.
"It could be a number of companies," Fitzgerald said. "This is a compound that was used widely in the United State and it is very persistent in the environment. Yes, we are concerned there are other sites around New Hampshire where we could potentially have problems."