IAI was the General Contractor for all landside operations on the Ottawa River Remediation Project, which was conducted over the course of the 2010 construction and dredging seasons. The project involved hydraulic dredging of 242,000 cubic yards of contaminated sediment from the Ottawa River near Toledo, Ohio. The dredged sediment was pumped by the dredging contractor from the river to the Hoffman Road Landfill Facility in Toledo, where two separate dewatering pads had been constructed for the purpose of dewatering the dredged sediment. Toxic Substances Control Act (TSCA) regulated sediment was pumped to the TSCA dewatering pad for chemical conditioning and dewatering in geotextile tubes. Sediment not regulated by TSCA was pumped to the Non-TSCA dewatering pad where the dredge slurry was injected with polymer, screened and thickened, and dewatered in geotextile tubes. Storm water from the dewatering pads, clear water from the sediment thickeners and water released from the geotextile tubes was collected and treated in a temporary on site wastewater treatment plant (WWTP). Over 500 million gallons of water were treated in the WWTP.

Remediation Services

• Sediment treatability work to identify chemical conditioners and dosage rates
• Installation and operation of polymer make down and feed system
• Installation and operation of debris screening and sediment thickening equipment
• Design, installation and operation of the TSCA and Non-TSCA geotextile tube header systems
• Design of the TSCA and Non-TSCA sediment dewatering pads
• Design, deployment and operation of the geotextile tubes
• Design, construction, start-up, operation and maintenance of the 4,000 gpm wastewater treatment plant (WWTP), configured with lamella inclined plate clarifiers, pressurized multi-media filters, bag filters and Granular Activated Carbon (GAC) adsorption units
• General site conditions for all landside functions, including site security, utilities installations, parking area construction and provision of site office trailers
• Landside health and safety, including design and installation of personnel and equipment decontamination areas, determination and enforcement of site work zones, development and implementation of a written site-specific health and safety plan, and air monitoring
• Decontamination and demobilization of TSCA and Non-TSCA geotextile tube header systems and WWTP equipment

Sediment Dewatering & Water Treatment Equipment Utilized

• 41,125 lineal feet of geotextile tubes, 75 – 85 feet in circumference
• (2) separate 8 inch diameter fused HDPE geotextile tube header systems
• (2) 31,000 gal sediment thickeners, operated in parallel, with pre-screening
• 400 gpm emulsion polymer makedown and feed system and injection header
• 4,000 gpm design flow wastewater treatment plant

Project Photos