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No elevated gas readings found in homes near Duvall closed landfill


Air-quality tests have revealed no trace of methane gas in homes near the Duvall closed landfill where King County employees recently recorded elevated readings of the gas.


No trace of methane gas has been found in air-quality tests from homes near the Duvall closed landfill, where elevated readings of the gas were recently recorded at a monitoring well.

On Thursday, July 27, King County Solid Waste Division employees notified owners of 26 homes in the immediate vicinity of the landfill about the presence of methane gas at the closed landfill, and to offer free in-home air-quality testing.

To date, none of the 18 homes tested have had any methane present in the samples. Three homeowners declined the offer to test, and five homeowners have not responded to the offer to test.

The closed landfill will be monitored daily until the methane gas readings are back to within regulatory levels.

The 13-acre Duvall closed landfill is located in unincorporated King County between Woodinville and Duvall and closed in the 1981. Due to its age and the regulatory requirements at that time, a landfill gas collection system was never integrated into the site. Since then, King County has installed monitoring equipment and protocols for regular testing for the presence of gas.