Cleanup of Legacy Soil and Groundwater Contamination
Cleanup of Legacy Soil and Groundwater Contamination at Former Automotive Parts Manufacturing Facility
Client: Automotive Parts Manufacturer | Location: Nebraska
Weaver Consultants Group’s (WCG) Remediation Services team provides environmental and remediation services associated with legacy contamination from former manufacturing operations at an automotive parts manufacturing facility in Nebraska, which operated from the 1960s to 2012. It formerly housed various petroleum products and hazardous substance Underground Storage Tanks (USTs), chromium plating and degreasing operations, underground conveyance and sewer lines, D and F listed waste and process water management and treatment operations, and former solid waste surface impoundments.
Numerous spills, operations, UST releases, and Solid Waste Management Units (SWMUs) have impacted subsurface soil and multiple aquifers with Chlorinated Volatile Organic Compounds (CVOCs), specifically Trichloroethene (TCE). A groundwater monitoring program and corrective action, including a groundwater extraction treatment system utilizing an air stripper tower, has been conducted since 1984 as part of Resource Conservation and Recovery Act (RCRA) Post-Closure Permit requirements.
WCG replaced a previous consultant conducting the cleanup efforts, which stalled over the past 10+ years. WCG took over the RCRA corrective action, post-closure permitting, and facility assessments and investigations to meet the US Environmental Protection Agency (USEPA) and Nebraska Department of Environment and Energy (NDEE) cleanup deadline.
The client requested WCG’s involvement under an accelerated timeline to review, refine, and optimize the remedial program for the most cost-efficient and effective resource allocation to meet the cleanup deadline.
WCG implemented the following actions to meet NDEE and USEPA requirements:
- Implement a Soil Vapor Extraction (SVE) pilot test, then expand and implement SVE system and performance monitoring program to reduce vadose zone TCE impacts within the soil, a contributor to shallow groundwater impacts.
- Investigate and characterize shallow (<10 feet) TCE groundwater impacts and evaluate potential vapor intrusion to refine the Conceptual Site Model further.
- Prepare Remedial Action Plan to remove the free product and close an oil UST release through the NDEE Risk-Based Corrective Action closure program and UST reimbursement program.
- Groundwater extraction treatment system optimization and upgrades, by-passing the air stripper tower, which was not needed to meet National Pollution Discharge Elimination System (NPDES) discharge requirements.
- Amend an outdated Sampling and Analysis Plan (SAP) using no purge sampling techniques and optimizing the Groundwater Monitoring Program within the three water-bearing zones (0-29-ft, 30-100-ft, 101-200-ft)
- Conduct a Focused Feasibility Study to evaluate and select the most beneficial and effective remedial strategy to reduce the contribution of TCE impacts from soil to groundwater.
- Develop a complex Materials Management Plan and implement a unique “Hot Spot” soil excavation, management, and remedial approach to remove/reuse TCE impacted soil by constructing treatment cells for vapor extraction treatment system.
- Design and implement a Tracer Study/Groundwater Monitoring Program to assess “Hot Spot” treatment efficacy to mitigate soil-to-groundwater TCE migration.
- Perform a Vapor Intrusion Evaluation to determine whether VOCs in the soil vapor and beneath mobile homes and a commercial property present a risk to human health or the environment.
- Address remaining requirements of RCRA Post-Closure Permit for closure of former hazardous waste surface impoundments.
- Prepare amended RCRA Facility Investigation for SWMUs and other areas of concern as part of Post-Closure Permit requirements.