AIRWAY HEIGHTS, Wash. (AP) — Officials in the Spokane suburb of Airway Heights say city tap water is now safe to drink.

Residents were told not to drink city water May 16 after tests by Fairchild Air Force Base found groundwater tainted with two industrial chemicals used for years in firefighting foam and consumer products such as nonstick cookware.

For weeks now residents have been driving up to a station set up behind a grocery store to get bottled water.

Airway Heights Assistant Fire Chief Don Malone on Thursday said the latest round of tests found 20 of 21 samples at acceptable levels for the compounds commonly known as PFOS and PFOA. Officials have closed off the site where the one sample detected contamination above federal guidelines.

The city has flushed millions of gallons of water through the city's pipes and water system hoping to remove the compounds.