He allowed the polluted soils to remain in place and be remediated through phytoremediation, and sequestered soils with high toxicity in the existing bunkers.
Instead of excavation or extraction for above-ground treatment or disposal, tetrachloroethylene contamination has been successfully remediated by chemical treatment or bioremediation.
Costs include costs to clean up or remediate contaminated sites, environmental fines, penalties and taxes, purchase of pollution prevention technologies and waste management costs.