Segmented trenches for recovering contaminant plumes from lined waste impoundments

This study examined the capability of segmented trenches with various placements to remediate groundwater contaminated by small holes in lined waste impoundments such as landfills. A groundwater flow and mass transport model simulated a small contaminant source above an unconfined alluvial aquifer. After the leachate plume evolved for 1,000 days, the source was shut off and clean-up trials commenced. Decoupled trench configurations, with one segment at the downgradient edge of a plume, and the other at high concentrations within the plume, expedited cleanup while limiting downgradient travel. At some sites, relatively efficient schemes documented here may be effective clean-up alternatives for contemporary landfills.