Kalamazoo Area 1 CVSC Sediment Dredging & Remediation

Forgen was tasked with conducting sediment removal at the Allied Paper Inc./Portage Creek/Kalamazoo River Superfund Site in Cooper Township, Michigan. We needed to safely and effectively remove side channel sediments contaminated with non-TSCA Polychlorinated Biphenyls (PCBs) (and TSCA if encountered). Additionally, we had to prevent river flow into and out of the side channel and control sediment re-suspension and migration during dredging to protect the surrounding environment and water quality.

To tackle these challenges, our team developed a comprehensive and meticulous working plan for this heavy environmental and heavy civil construction project. We installed a temporary steel sheet pile cofferdam to isolate the side channel from river flow, preventing water from entering or leaving the area during operations. We also deployed impermeable turbidity curtains within the side channel to minimize sediment re-suspension and prevent contamination migration during dredging.

The project team used a John Deere 250G long-reach excavator equipped with GPS technology for precise excavation, operating from a floating Poseidon barge platform. We dredged the side channel to depths of 5 feet below existing grades, ensuring thorough sediment removal. We then loaded the dredged material directly or relayed it to a sediment transfer box, transferring it into 30-ton articulating trucks with modified tailgates designed to contain the liquefied PCB impacted materials. These trucks safely transported the contaminated sediment to the on-site Sediment Processing Area (SPA) for stabilization.

To maintain the integrity of on-site haul roads leading to the SPA, our team installed HDPE mats, ensuring that the transportation of materials did not degrade the pathways. We contained all contact water on-site and treated it using a 100-gallon-per-minute water treatment system. After rigorous analytical testing which included confirming PFAS removal, we discharged the treated water back into the Kalamazoo River.

Forgen stabilized the dewatered sediment material by homogenously mixing it with Portland cement and quicklime using excavator bucket mixing until achieving a cohesive stabilized material. The stabilized material was then loaded into trucks for off-site transportation. Forgen disposed of the stabilized material at approved licensed facilities, using two different waste disposal facilities based on the levels of acceptable PFAS constituents.

Our team successfully removed contaminated sediments from the Crown Vantage Side Channel. We installed a temporary cofferdam and turbidity curtains to prevent river flow and control sediment migration, protecting the environment and water quality.

Using precise GPS-guided dredging operations, Forgen thoroughly removed contaminated sediments to the specified depths. During this project, our team mechanically dredged over 11,000 cubic yards of PCB sediments. We transported over 17,000 tons of sediment for off-site disposal and used 1,500 tons of Calciment/quicklime reagent for soil stabilization.

Forgen treated all contact water on-site and safely discharged it back into the Kalamazoo River, meeting all federal and state permitted environmental and safety standards. By stabilizing the dredged sediment material with Portland cement and quicklime, our team ensured it was suitable for off-site disposal. We used approved licensed disposal facilities and complied with all regulatory requirements, particularly concerning PFAS constituents.

Our comprehensive and methodical approach led to the successful remediation of this contaminated site. Forgen’s expertise in managing complex environmental projects and our commitment to environmental protection and regulatory compliance ensured the project’s successful completion.