PORTSMOUTH — Portsmouth public works officials shut down one of the three wells servicing Pease International Tradeport on Thursday, after tests by the U.S. Air Force and state health and environmental departments found excessive levels of a chemical contaminant.
Mike Wimsatt, director of the waste management division at the New Hampshire Department of Environmental Services, said Thursday that he hadn’t received any reports of health issues or concerns related to drinking water at Pease.
“None whatsoever,” Wimsatt said, noting that the other two wells at Pease remained in service. “The water that’s provided to tradeport customers is safe to drink, so there’s no cause for concern at present.”
The state’s waste management division oversees cleanup efforts at Pease, which was a U.S. Air Force base from 1956 to 1991 and remains a Superfund site that the Air Force is cleaning up, with additional oversight from the U.S. EPA.
The tradeport is home to more than 245 companies that employ a total of more than 7,000 people, according to its website.
Dave Mullen, executive director of the Pease Development Authority, said Thursday that the Haven Well’s closure hadn’t affected water services at Pease. Mullen said the city of Portsmouth operates water services at the tradeport and could supplement water supplies if necessary.
“The well that’s the source of the problem is no longer in use,” Mullen said. “The key thing is that the Air Force found the problem, we shut it off and we’re working with the city toward a solution.”
The New Hampshire departments of environmental services and health and human services said Thursday that the contaminant was one of a class of chemicals known as perfluorochemicals, or PFCs. Portsmouth’s water system was not affected, the departments said.
“Out of an abundance of caution, the water system for the city of Portsmouth was also recently tested, since the systems at Pease and Portsmouth are linked, however, water from the Pease wells is rarely used to service the city of Portsmouth,” a statement from the departments read. “The results were that no PFCs were detected in any of the other supply wells or surface water sources that serve the Portsmouth water system.”
The closed well also serves the New Hampshire Air National Guard base at Pease.
The state departments said Air Force operations decades ago could have led to the contamination.
“It is suspected that firefighting foam used by the Air Force starting around 1970 for plane crashes and training exercises contained PFCs that leached into the ground and consequently contaminated the well,” the departments said.
Water samples from the other two wells servicing Pease also contained PFCs, but not at levels in excess of health advisory levels set by the EPA, according to the departments.
Wimsatt said the samples that led to Thursday’s closure were taken in April and confirmed this month.
“We do know that the EPA set a very conservative health advisory number for this contaminant,” Wimsatt said. “We don’t really know whether that translates to adverse health risks. It’s a very conservative number that’s based on limited information that the EPA has available to it.
“You like to be able to speak in very definitive terms, but unfortunately we don’t have the data available” to discern whether there are potential health risks, he added.