MARTINSBURG, W.Va. — The U.S. Air Force has agreed to reimburse Martinsburg $4.9 million for expenses that the city incurred in response to water-supply contamination linked to the 167th Airlift Wing of the West Virginia Air National Guard, U.S. Sens. Shelley Moore Capito and Joe Manchin announced Wednesday.

“I’m so thrilled that the Air Force has finally put forward an agreement that will help recuperate the significant costs Martinsburg incurred during the cleanup of their water supply,” Capito, R-W.Va., said in a news release.

“When faced with this serious public-health challenge, the city stepped up to protect the health and well-being of the community and its residents, and that was neither an easy nor an inexpensive effort.”

Manchin, D-W.Va., said Wednesday in a separate news release that he is glad to see the U.S. Department of Defense working with Martinsburg “to take ownership of a problem we have been trying to solve for three years.”

“I will continue to encourage the department to act in the best interests of impacted communities, and support efforts to develop groundwater and drinking-water standards that will protect the public from the health hazards associated with PFAS contamination,” Manchin said in the release.

The cleanup of perfluoroalkyl and polyfluoroalkyl substances, or PFAS, at the city’s Big Springs Water Plant began shortly after the U.S. Environmental Protection Agency announced a health advisory standard for human exposure to the chemical in May 2016.

The EPA announcement prompted the city to temporarily take the water plant off U.S. 11 south of Martinsburg offline due to a higher level of the contaminants being sampled in the water-supply source.

The water plant went back online in December 2017, and city officials have said the upgraded system has performed well since.

City Manager Mark Baldwin said Wednesday that Martinsburg will recoup construction, engineering and other costs incurred as a result of the cleanup.

“Our federal lawmakers have worked very hard for us,” he said.

Wednesday’s announcements come three months after the Centers for Disease Control and Prevention and the Agency for Toxic Substances and Disease Registry jointly said in February that Berkeley County near the 167th Airlift Wing was among eight communities across the United States selected to be part of assessments of human exposure to the contaminants.

The assessment work is to continue into 2020.

PFAS are manmade synthetic chemicals used in industry and consumer products since the 1940s. They also have been used in nonstick cookware; water-repellent clothing, stain-resistant fabrics and carpets; cosmetics; and firefighting foam.

Authorities determined after the EPA’s announcement in 2016 that the chemical contaminants migrated into Martinsburg’s water source from the 167th Airlift Wing base at Eastern West Virginia Regional Airport, where the firefighting foam in question was used.

As part of a continued effort to prevent future PFAS contamination and protect public health, Capito said Wednesday that she has introduced two PFAS-related bills — the Protect Drinking Water from PFAS Act of 2019 and the PFAS Release Disclosure Act.

The PFAS Act of 2019 would require the EPA to establish an enforceable standard under the Safe Drinking Water Act for PFAS in drinking water.

The PFAS Release Disclosure Act would provide a process for the EPA to identify and publicly share sources of PFAS emissions.