A map of where officials are looking at PFAS in Loring.
A map shows the Air Force Civil Engineering Center's main areas of investigation (in purple) to determine how far PFAS chemicals have spread at the former Loring Air Force Base. Credit: Courtesy of U.S. Air Force

LIMESTONE, Maine — Although PFAS contamination hasn’t been found in drinking water supplies in the area around the former Loring Air Force Base, the use of a PFAS chemical to put out fires on Loring’s runway has prompted the U.S. Air Force to examine how far the chemical has spread into the natural environment.

Looking into the spread of Aqueous Film Forming Foams, or AFFF, and assessing the potential ecological and human health risks is the latest phase in the Air Force’s investigation into PFAS contamination and will include a public meeting next week for area residents to ask questions.

PFAS substances, also known as “forever chemicals,” have been found in farm soil and animals and in the state’s  wild deer herd, among other places in Maine. It is the state’s largest growing health concern.

Starting in 2015, members of the Air Force’s Civil Engineering Center took smaller samples from 22 major groundwater, surface water, soil and sediment areas at Loring to verify whether AFFF existed. The yearlong study verified the chemical’s existence, so researchers began a more detailed analysis.

While the Environmental Protection Agency mandates that PFAS levels not exceed 70 parts per billion to be deemed safe in drinking water, the Loring investigations have thus far not found fire foam in private wells or public drinking water systems.

Only single-digit parts per billion levels of fire foam have been found in the surveyed sites, according to Val de la Fuente, chief of the Civil Engineering Center’s Eastern Executive Branch.

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But the mere presence of PFAS, a group of manufactured chemicals known to cause cancer, birth effects and other health risks, means that the Air Force must conduct a study on how far the chemicals at Loring have spread and how they might be removed, de la Fuente said.

“Our initial investigation found that 21 of our 22 sites require further investigation,” de la Fuente said. “We have to look at where the water [that drained from the runway fire sites] has gone and how far [the fire foam] has spread. It’s not just drinking water but also soil, sediment, groundwater and surface water.”

The investigation will include at least 1,300 total samples of groundwater, stormwater, surface water, soil, sediment and fish in and around the region now known as Loring Development Authority, a commercial, industrial and aviation park on the site of the former Air Force base.

Though portions of the study will be conducted on Loring Development Authority-owned property, researchers and LDA officials do not yet know if any PFAS monitoring wells will be placed near manufacturing facilities, Loring Job Corps Center or other businesses.

Sampling for the fire foam began in May and will continue throughout fall 2022. Sites will include waterways such as Limestone Stream, Little Madawaska River, Chapman Pit, Durepo Reservoir, Greenlaw Brook, Malabeam Lake and Butterfield Brook.

Once that investigation and the sample analysis conclude, de la Fuente’s team will release its findings and start determining how to remove the fire foam chemicals. Unlike previous environmental clean-ups at Loring, which operated from 1950 to 1994, removing the fire foam will take many years, de la Fuente said.

“Loring had petroleum spills and chlorinated solvent leaks but those were contained to specific areas. We were able to remove the soil and now we just monitor [the area] to make sure levels stay down,” de la Fuente said. “But [the fire foam residue] has spread.”

As the investigation continues, Air Force officials will communicate with landowners in and around what is now the Loring Development Authority. They will also conduct community meetings to inform the public on developments.

Air Force Civil Engineering Center officials, including de la Fuente, will hold a public meeting at 5:30 p.m. on Wednesday in the Limestone Community School auditorium to address questions.