American Chemical Service

"Providing Full-Service Soil and Water Remediation"

What's the safest way to prevent chemicals from a manufacturing plant (and former solvent recycling facility) from migrating into soil and water?

MWH tackled that challenge in our work for American Chemical Service. We provided full-service, turnkey soil and groundwater remediation services on a site that is currently an active chemical manufacturing operation. It's also a former solvent recycling facility for companies in the Chicago and northern Indiana area of the United States.

Decades of chemical handling and processing at the facility had produced subsurface ground contamination. These waste materials posed no immediate threat to human health or the environment. However, the possibility of chemicals migrating from the site over time was deemed unacceptable. The site was added to the Superfund list in September 1984.

Innovative Subsurface Barrier

A consortium of companies ranging from multinationals to small, regional firms funded MWH’s efforts. Our activities included:

• Investigating the site to determine the type and extent of contamination
• Designing appropriate remedial strategies
• Implementation of these remedial programs

MWH moved quickly to stabilize the site and eliminate potential off-site migrations. Our experts used pre-design investigations to help refocus the remedial approach.

They also negotiated a modification to the EPA's Record of Decision (ROD) remedy that saved the client at least $100 million in remedial costs. The new remedy consisted of a combination of containment and contamination treatment by In-Situ Vapor Extraction. It equaled the original remedy in protecting human health and the environment. However, it was a safer method that was much less costly to implement.

MWH designed a state-of-the-art groundwater remediation system that features an innovative impermeable barrier wall consisting of high density polyethylene (HDPE) and soil bentonite slurry to contain the buried waste. The system also features phase separation, biological treatment, metals precipitation and carbon polishing to treat water so it can be released directly to the wetlands west of the site.

Our experts also garnered EPA approval to use a design-build approach on the project. This allowed our experts to modify design components in real time during construction. It also allowed regulators to provide immediate feedback and approval. This approach saved the client hundreds of thousands of dollars. Overall design costs were minimized, and numerous cost-saving construction steps were implemented during the building process.