A screenshot of the Washington State Department of Ecology's 'Dirt Alert' web mapping application showing the Tacoma Smelter Plume tab, displaying predicted arsenic soil concentrations across the south King County / Pierce County area including SeaTac, Des Moines, Vashon Island, and Maury Island. The legend indicates concentration zones ranging from under 20 ppm (light yellow) to over 100 ppm (dark purple), with SeaTac Airport and surrounding communities falling within the 40.1–100 ppm range.Open full document
Notes
A screenshot of the Washington State Department of Ecology’s ‘Dirt Alert’ web mapping application showing the Tacoma Smelter Plume tab, displaying predicted arsenic soil concentrations across the south King County / Pierce County area including SeaTac, Des Moines, Vashon Island, and Maury Island. The legend indicates concentration zones ranging from under 20 ppm (light yellow) to over 100 ppm (dark purple), with SeaTac Airport and surrounding communities falling within the 40.1–100 ppm range.
