Known Toxic Sites
Superfund Sites are described as "Thousands of contaminated sites exist nationally due to hazardous waste being dumped, left out in the open, or otherwise improperly managed. These sites include manufacturing facilities, processing plants, landfills and mining sites." EPA, What is a Superfund?
For more information on this please see Environmental Protection Agency
Search for Superfund Sites in the Pacific Northwest and Alaska.
Washington State Department of Ecology Site Clean-up Search Page
State identifies more toxic sites needing cleanup
Washington State Department of Ecology,Toxic Cleanups: Hazardous Sites List