Tony,
Part of what is the city of Dupont used to be the manufacturing site for the Dupont munitions factory. The Weyerhauser Company purchased the 3200 acre site after the Dupont Powder Works closed and started to develop the area into the Northwest Landing planned community. Because some of the areas showed increased levels of lead and arsenic in the soil, Weyerhauser had to present a soil remediation and land use plan to the city, as well as the state ecology department before they could go on with their development plans. I'm not sure as to the full extent of the requirements, but some of it included scarping soil. As far as I know, the clean-up has been completed and blessed off by all agencies involved. I believe the greatest concern with building on a site that showed traces of lead and arsenic, were ground water pollution. I don't think radiation was ever a concern (Dupont Powder Works
did not manufacture depleted uranium ammunition).
You might find these documents, detailing the process, an interesting read:
http://www.ecy.wa.gov/programs/tcp/s...eyer_Sec_2.pdf
http://www.ecy.wa.gov/programs/tcp/s...eyer_Sec_3.pdf
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dupont? radiation?
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