contaminated layer

Concrete shavers were later used to scrape off the contaminated layers.

If contaminated sediment is deposited back on top of the cap then a cap was built to separate to contaminated layers.

In many places in the dredging zone — the upper Hudson above Albany — the contaminated layers of sediment were far thicker than sampling probes had predicted.

Officials said the long-term plan was to restore the area to its pre-flood state by removing contaminated layers of soil from nearly 1,000 hectares (2,500 acres) of residential and agricultural land.

Lawrence Livermore National Laboratory has created a new material for military uniforms that can automatically repel chemical and biological agents -- and shed contaminated layers like a snakeskin.

Bioventilation technology for soil treatment involves injecting air into the contaminated layer to encourage biodegradation of organic contaminants (light hydrocarbons, gasoline, diesel) and draw them out with the gaseous effluent.