ENTACT completed the multi-phase remediation of a 100-acre industrial site near a river in preparation for mixed-use redevelopment. The initial phase covered 34 acres in the central portion of the site and lasted 3.5 years.

We excavated approximately 932,000 cubic yards of chromium ore process residue (COPR) and chromium-impacted material and transported 53,000 truckloads for disposal off-site. To reduce water content in the waste materials, ENTACT designed, installed, and operated a groundwater extraction system. Finally, we imported, placed, and compacted approximately 880,000 cubic yards of backfill to bring the site to the final surface grades.

The second remediation phase was completed over three years and was located north and south of the previously remediated area. ENTACT designed, installed, and operated a vacuum well point and deep well groundwater extraction system to reduce the amount of groundwater at the site. We placed over 400,000 cubic yards of surcharge materials in a rolling fashion over the north and south areas for subgrade consolidation.

On the perimeters of the north and south areas, we installed over 180,000 square feet of epoxy-coated sheet pile with grouted or sealed interlocks. We excavated 250,000 cubic yards of overburden and chromium-impacted soil to a maximum depth of 20 feet below ground surface and disposed of off-site. ENTACT imported, placed, and compacted 285,000 cubic yards of backfill to bring excavated areas to subgrade elevations. Finally, we constructed two 10-acre capping systems consisting of geosynthetic and cover soil components and installed a gas venting and groundwater extraction system within capped areas.