- AECOM Technical Services
- East Greenwich, RI
The Stanley Black and Decker Former Storage Area (FSA) is a 5.4-acre site bounded by farmland, an undeveloped forest, a seasonal stream, and wetlands where wastes from manufacturing operations were disposed from 1956 through the 1980s. Wastes included items such spent solvents, metal turnings and debris, glues, plating wastes, heat treatment wastes, mineral spirits, and tumbling wastes. The scope of work involved the excavation of impacted material above Rhode Island Department of Environmental Management (RIDEM) criteria for onsite reuse.
Challenges and Solutions
The work included excavation of cadmium stockpiles and volatile organic compound hotspots followed by backfill with sand-blended zero valent iron to achieve compliance with RIDEM standards. Impacted soil was blended with zero valent iron and used to create a reactive barrier wall along the northern and eastern sides of the facility in conjunction with the soil cap to mitigate groundwater and direct surface water seepage into surrounding areas.
Hotspot excavations were performed to remove cadmium and volatile organic compounds (VOCs), excavation of a barrier trench to bedrock to prevent any remaining VOCs in the groundwater from leaving the site, and stream bank and culvert restoration. The entire site was stripped to 2+ feet below existing grade to remove any waste materials and debris and then sorted for use as part of the landfill cap.
The hotspot excavation operation was conducted in cells with confirmatory sampling to determine the extent of contaminated soils. Throughout the deep excavation, the crew had to work around large boulders and with seasonal groundwater changes. To combat this issue the operation had constant management and treatment of soils. Once the excavation was completed, hotspots were backfilled with treated soils and clean fill which were mixed with Zero Valent Iron to neutralize any remaining VOC’s.Back to all