MONTGOMERY COUNTY — Elevated levels of per- and polyfluoroalkyl substances (PFAS) were detected in a stormwater pond and a nearby stream in Montgomery County, Maryland. The affected waterways are located near Great Seneca Highway and Key West Avenue in the Gaithersburg and Rockville areas.

Montgomery County issued a health advisory, and red temporary fencing was installed around the contaminated pond to restrict access for people and pets. County officials advised residents to stay out of the affected waterways, keep pets away, and avoid eating any fish caught there. Officials stated that tap water in the area remains safe.

The Maryland Department of the Environment identified the high PFAS levels. Jennifer Macedonia, Director of the Montgomery County Department of Environmental Protection, said, "The state's testing detected high levels of PFAS in an area on and adjacent to the site of the county's former public safety training facility." Firefighters trained at that facility for decades until 2015, and officials stated the contamination may be connected to chemicals used in firefighting foam there.

WSSC Water requested additional testing in the Muddy Branch area, which led to the discovery of the high PFAS readings. Laura O'Donnell, PFAS Program Manager at WSSC Water, said, "I want our WSSC Water customers in Montgomery and Prince George's counties to know that the water we provide is safe." She added, "This is not a public water supply issue."

Montgomery County Executive Marc Elrich stated, "The county is taking this issue and the concern very seriously, and it's taking steps to inform the public and protect public health and the environment." He also said, "This stuff is ubiquitous and it's not always easy to figure out where it came from, but it's there now." The county is offering free PFAS testing to homeowners with private wells within one mile of the highest sampling locations. Additional testing is underway to determine the extent of the contamination.

Macedonia said, "The County is working with the Maryland Department of Environment to identify the extent and locations of contamination to inform our next steps to protect public health and the environment. We will conduct additional testing, including groundwater and soil to inform remediation plans." The Environmental Protection Agency indicates that exposure to certain levels of PFAS can lead to health risks, including cancer, developmental delays in children, and hormone interference.

PFAS are manmade chemicals that do not break down and can accumulate in the environment and the body. The county stated that these chemicals have been used in industrial processes and consumer products since the 1940s. Montgomery County filed a lawsuit in 2023 against manufacturers of PFAS, alleging they concealed risks while profiting from the chemicals and failed to warn users and the public. Elrich said, "We also intend to continue pursuing accountability from the manufacturers of PFAS-containing products that have contributed to contamination in communities across this nation." Montgomery County scheduled a community meeting for 7 p.m. on Wednesday at DuFief Elementary School.