First Environment conducted the investigation and remediation of this 28-acre site, which became part of the New Jersey ECRA/ISRA process. Located adjacent to the South Branch of the Rahway River, the site’s challenges included a wide range of contaminants of concern—including volatile organic compounds (VOCs), heavy metals, and polychlorinated biphenyls (PCBs— and a variety of areas of concern including buried drums, underground storage tanks, and outfalls. The site remains an active manufacturing facility that has operated throughout the investigative and remedial activities.
First Environment performed the remedial investigation in phases. During the early phase of the investigation, the project team identified 20 potential buried drum sites which they investigated via test pits, ultimately identifying 11 areas requiring remediation. The remediation activities consisted of excavation and segregation of drums from impacted soils. First Environment developed, classified, and transported two waste streams for off-site disposal.
Midway through the project, the New Jersey Department of Environmental Protection (NJDEP) adopted new (and in some cases, more stringent) soil cleanup criteria. The adoption of the new rules prompted the investigation of a larger portion of the buried drum areas. The investigation—for which First Environment collected 180 soil and sediment samples from 109 locations—successfully delineated the area of heavy metals-impacted soil within the buried drum areas. First Environment also coordinated and oversaw the excavation and disposal of approximately 6,000 tons of soil and sediment that contained elevated concentrations of cadmium, chromium, and lead.
In order to evaluate remedial alternatives and disposal options for the soil, First Environment conducted a feasibility study. The study identified a nearby beneficial use project that provided the client with a cost effective remedial option.
During follow-up investigation activities, PCBs were identified within the floodplain and riverbed adjacent to the site. First Environment completed the delineation (horizontal and vertical) of PCBs and ecological impacts in the floodplain and river channel, submitting a Remedial Investigation Report and Ecological Risk Assessment Workplan to NJDEP. NJDEP approved both of these documents, as well as First Environment’s Remedial Action Workplan detailing the remediation of approximately 3.5 acres of wooded wetlands/floodplain and portions of the river channel. As with the previous buried drum area remediation activities, the work area is located in wetlands within the 100-year floodplain. As a result, First Environment completed a wetland delineation survey, soil erosion sediment control plan, freshwater wetland, stream encroachment, and waterfront development permits. The permits and regulatory approvals were secured for the drum area remediation as well as the floodplain/river channel remediation.
In addition, the project team was required to secure authorization from the NJDEP Land Use Regulation Program (LURP), Soil Conservation District, and U.S. Army Corps of Engineers in order to obtain the regulatory authority to begin the project. NJDEP issued No Further Action for the remediation of the buried drum areas. The project ultimately consisted of the excavation, backfilling, and restoration (grading, wetland plantings, etc.) of approximately 3.5 acres and two areas of the river channel.
A subsequent phase of the investigation focused on the leaking underground tanks. First Environment conducted soil vapor screening to determine the extent of VOCs above NJDEP guidelines and to optimize the location of soil borings requested by NJDEP. The concentrations of total VOCs found in these soils ranged from 10 to 16,000 ppm.
In addition to the soil remediation activities at the site, First Environment has also investigated and remediated the groundwater underlying the site. Leaking USTs resulted in a VOC plume, for which First Environment designed and installed a soil vapor extraction (SVE) and groundwater recovery treatment system which continues to operate at the site. First Environment operated the system by conducting weekly operation and maintenance (O&M) visits as well as ensuring permit compliance for both air and water, which involved monthly discharge monitoring reports (DMR) to the local POTW. First Environment also installed a series of injection wells and completed in-situ chemical oxidation (ISCO) events utilizing hydrogen peroxide to supplement the SVE and groundwater treatment system.