Case Studies

Manufacturing Site in Michigan

Challenge: WSP Environment & Energy was retained by an automobile parts manufacturer to review a soil flushing and groundwater containment system. The 8-year old system was preventing the migration of a plume of chlorinated solvents. Soil at a former plating line was being treated by flushing hexavalent chromium from the soil to the groundwater for collection and treatment by the pump and treat system.

Solution: WSP Environment & Energy reviewed the available soil and groundwater characterization data and recommended aggressive source reduction. The proposed strategy included in situ treatment of hexavalent chromium. This transformation process immobilized the chromium. Air sparging and soil vapor extraction were recommended to accelerate the removal of the chlorinated solvents from the soil and groundwater.

Result: The review enabled the client to adopt a course of action that reduced the projected endpoint for the groundwater system by 10 years resulting in a savings of $1,000,000. Furthermore, the accelerated remediation of the site under Michigan's Part 201 regulations improved its marketability, enabling it to be sold before the remediation was completed.

Manufacturing Site in Pennsylvania

Challenge: WSP Environment & Energy was retained by a manufacturer to review a pump and treat system at an inactive facility. The system, which had been operating for 10 years, was removing large volumes of water containing less than 100 µg/l of chlorinated volatile organic compounds (VOCs). The VOCs had affected a municipal water well approximately 200 feet downgradient, which had an air stripper installed by the client and operated by the municipality.

Solution: WSP Environment & Energy entered the site into Pennsylvania's Land Recycling and Environmental Remediation Standards Act (Act 2) program. We demonstrated to the state that the pump and treat system was no longer significantly cleaning up the groundwater and we were allowed to turn off the system. Subsequently, our client received a release from liability under Act 2 for the VOCs in the groundwater.

Result: The remediation review enabled the client to turn off the pump and treat system in less than 2 years. Only 8 quarters of groundwater monitoring were required for post-remediation care. The net cost savings was at least $500,000, since it is uncertain how long the state would have required the treatment system to run. Addressing the site through the Act 2 program limited the liability and enabled the client to sell it.

Manufacturing Site in Pennsylvania

Challenge: WSP Environment & Energy was retained to review the status of manufacturing facility that had closed in the early 1990s. The client wanted to restore the property so it could be sold for commercial development. Soil at the property was contaminated with petroleum hydrocarbons, chlorinated solvents, barium, and cyanide; the groundwater had not yet been investigated.

Solution: We recommended putting the site in Pennsylvania's Land Recycling Act 2 program, because its flexibility would enable the property to be sold with minimal investment in remediation. We were then retained to investigate the site in accordance with the Act 2 requirements. A focused investigation and analysis of potential exposure pathway, we demonstrated to the state that the contaminated soils had not affected the groundwater. Furthermore, we showed with institutional controls in place, there would be no risk to potential receptors. The state agreed, requiring only two quarters of additional groundwater monitoring to issue a release from liability under Act 2 for the soil contaminants.

Result: The client will be able to sell this property without having to implement extensive soil remediation, which had been estimated to cost from $300,000 to $500,000.

Manufacturing Facility in Virginia

Challenge: WSP Environment & Energy was retained to review a pump and treat system operating at a manufacturing facility. The system had been installed in accordance with a RCRA post-closure permit that required corrective action for VOC-contaminated groundwater in the bedrock.

Solution: After evaluating the investigation and corrective action programs being implemented as part of the post-closure permit, WSP Environment & Energy developed a new strategy that consisted of source control and obtaining a technical impracticability waiver for the groundwater in the deep bedrock. We assisted this client in negotiating the HSWA permit that was being issued by the state. This resulted in several permit conditions being modified that will reduce the effort and overall costs required. Several solid waste management units were eliminated and no longer needed to be investigated.

Result: The permit modifications saved the client $250,000 by reducing the number of investigations required. The new remediation strategy will save over $2 million dollars by focusing efforts on source control rather than the technically impracticable remediation of groundwater in the deep bedrock. Also, the remediation will be completed in considerably less time.