REGENESIS were retained to carry out the remediation design and site application works to treat groundwater impacted with hexavalent chromium (CrVI) on the site of a former saw mill.
Metals Remediation Compound® (MRC) and 3D-Microemulsion® (3DMe) were applied into the groundwater to provide rapid reduction and immobilisation of the CrVI present. Groundwater samples collected 2 months after application were analysed for CrVI, returning non-detect results.
As the geology comprises weathered and fractured limestone, treatment was carried out via pre-installed treatment wells at a 5 m spacing in the source area and 6 m in the barrier.
MRC and 3DMe were co-applied into these wells to target the source area of contamination and to install a reactive barrier at the down-gradient edge of the site to protect a nearby watercourse. MRC and 3DMe provide a powerful combination of wide distribution and strong reducing and immobilising properties.
The 3DMe/MRC application achieved rapid reductions from concentrations of up to 15,000ug/L CrVI to below detection limits within 2 months (See graph below). These low concentrations were then maintained throughout the validation period (ongoing).