A US Government site had elevated TCE. Low aquifer pH stalled in situ bioremediation.
- Inject organic substrate in the aquifer to enable naturally-occuring bacteria to effect in situ anaerobic reductive dechlorination
- Control pH to sustain long-term performance
- Achieve regulatory remediation levels of 5 µg/L TCE in groundwater and 53 µg/kg TCE in soil
Test effectivness of buffered emulsified oil substrate.
- Sixteen wells paired to inject and recirculate EOS PRO
- Post-injection performance monitoring for 29 months
- Twenty direct push points to inject CoBupH MG
- Post-injection performance monitoring for 13 months
Buffered substrate overcame the stall in bioremediation caused by low pH. Phase I unbuffered injections resulted in up to 99% TCE reduction, but with little formation of vinyl chloride (VC) or ethene. Phase II buffered injections stimulated the reductive dechlorination process resulting in substantial increases in both VC and ethene.