Some of the groundwater on Wright Patterson Air Force Base is contaminated with PFAS, commonly known as forever chemicals, which have been linked with cancer and developmental problems.
Forever chemicals are extremely difficult to break down, so they end up sticking around for a long time in water, soil and the human body. The chemicals have been used to manufacture all sorts of things because of their unique properties—like anti-stick pots and pans, fast food wrappers and dental floss.
One source of contamination at Wright Patterson comes from something called AFFF (aqueous film-forming foam) that was used by firefighters on base. If those chemicals, which don’t break down naturally because of their strong chemical bonds, aren’t cleaned up, they can spread into local drinking water wells.
Using congressional funding, engineers at the base recently designed an interceptor trench to best capture contaminated groundwater so it can then be treated. Here’s a video and some pictures from base officials explaining how it works and showing its construction this Fall.
George Walters, a supervisory environmental engineer at Wright-Patterson AFB, said that, in essence, water from the contaminated sites on base that are currently being prioritized will settle in a thirty foot deep and four hundred foot long trench.
“This would basically guarantee capture of all the water,” he said. “Whereas extraction wells, if we could have put them in, you might have some dead zones where water could snake by.”
After the water is captured, it is pumped through an organic clay treatment filter on base and then discharged into local waterways.
Walters also said the new interceptor trench system and treatment facilities on base are going to need to be around for a long time. That’s, in part, because the US Environmental Protection Agency is expected to lower the levels of PFAS that are considered safe in drinking water.
“If the EPA keeps lowering the LHA (Lifetime Health Advisories) in the future and it's going to be as low as we're hearing, in the single digits (parts per trillion), the system will be operating for a very long time because at those levels it's practically raining PFAS,” Walters said.
Chris Welter is a reporter and corps member with Report for America, a national service program that places journalists in local newsrooms.
