The former Elizabeth Webbing Mills property was an abandoned mill complex consisting of 19 buildings situated on 4 acres of land adjacent to the Blackstone River. To support redevelopment of the mill complex to mixed residential/commercial use, 14 soil borings were advanced in the Phase I section of the Site. Arsenic, lead and several SVOCs were detected at concentrations exceeding their Residential Direct Exposure Criteria in several locations.
BETA developed a Remedial Action Work Plan in concert with site redevelopment plans that addressed the soil contamination through encapsulation coupled with the filing of an Environmental Land Usage Restriction (ELUR) and a Soil Management Plan in the land evidence records of the City of Central Falls. In landscaped areas, soil was excavated to a depth of 2 feet below existing ground surface and backfilled with a minimum of 2 feet of clean soil. Fill brought to the site was sampled for various parameters to verify it was clean. Before backfill was placed, an identifying marker in the form of snow fencing or other similar material was placed over remaining soil. In some areas, it was necessary to limit the depth of excavation to 1 foot or less. In these instances, a geofabric was placed at the bottom of the excavation prior to backfilling with clean compacted material.
Most of the existing pavement throughout the site was in disrepair and was replaced during redevelopment. The pavement and a minimum of 6-inches of soil were removed from all areas that were re-paved. The asphalt was crushed on-site and then placed over the remaining soil layer in a 3-inch to 4-inch lift, as part of the sub-base for the new pavement. Clean gravel was then placed over the crushed asphalt so that final depth of sub-base below the pavement was a minimum of 6-inches following compaction. Two-inches of bituminous base and 2-inches of bituminous surface course, laid in perpendicular lifts, were placed over the clean sub-base. All work was performed with the approval of the RIDEM.