adjust aquifer pH with CoBuphMg™
graph shows benefit of using CoBupHMg™ to adjust aquifer pH

Using CoBuphMg™ to Adjust Aquifer pH

This case study demonstrates how adding CoBupHMg™, a colloidal buffer, can control and adjust aquifer pH for enhanced bioremediation.

PROBLEM

A US Government site had elevated TCE. Low aquifer pH stalled in situ bioremediation.

PROJECT GOAL

  • 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

METHODOLOGY

Test effectivness of buffered emulsified oil substrate.

Phase I

  • Sixteen wells paired to inject and recirculate EOS PRO
  • Post-injection performance monitoring for 29 months

Phase II

  • Twenty direct push points to inject CoBupHMg™
  • Post-injection performance monitoring for 13 months

RESULTS

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.