01
Former coal-tar manufactured-gas site
US river sediment site
Background
A former coal-tar-based artificial gas manufacturing facility had discharged pollutants into an adjacent river system over the long term, contaminating roughly 4,000 sq ft of sediment.
Technology Used
Anti-methanogenic in-situ sediment capping
Approach
A three-layer cover system was installed over the contaminated sediment: a protective stone layer, an aquifer layer, and an organic bentonite base layer containing methane suppressants — extending contact time between the sediment and the reactive layer.
Results
- Effectively inhibited methane generation, avoiding local damage to the cap from gas bubbling
- Achieved the intended remediation objectives with no cap disruption