Project Summary
ORIN treated highly contaminated unsaturated soils using a combination of advanced oxidation treatment chemistry and bio-available absorbent media (BAM). The chemistries were applied separately and mixed into the soils with a modified excavator. Approximately 9,120 cubic yards of soil were treated ex-situ within contained treatment pits of 4-ft thickness. The treatment zone was excavated in 570 cubic yard batches. The Fenton’s treatment chemistry, a catalyzed hydrogen peroxide solution, was applied to break apart the clays, oxidize VOCs, and better homogenize the mixing of the BAM particulate. The site specific clean-up goal targeted less than 1.3 mg/kg TCE (or sufficiently meet TCLP standards), so as to allow the re-emplacement of treated soils into the subsurface. Post treatment composite samples determined the contaminant level reduction and need for retreatment if necessary.
Project Results
The TCE impacted soils were successfully treated to non-hazardous screening and re-emplaced back into the subsurface. Additional TCLP data was sampled from each batch to determine leachability. The combined average TCLP from all treated soils was 0.009 mg/L. Untreated excavated soils with samples in exceedance of 100 mg/kg TCE were treated for non-hazardous disposal. The site is now being developed as a multiple use commercial complex and parking lot.