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Fox River Project

50,000 Cubic Yards of Contaminated Sediment Removed

The removal of sediment contaminated with polychlorinated biphenyl's (PCBs) has been completed in Sediment Management Unit 56/57 (SMU 56/57) on the Lower Fox River in Green Bay. The dredging and dewatering operation was accomplished two weeks ahead of schedule, meeting the goal of removing 50-thousand CYs cubic yards (CYs) of PCB-contaminated sediment which was targeted for this year's project. Combined with the work performed at the site last year, a total of 80-thousand CYs of contaminated sediment have been removed from what is believed to be the worst "hot spot" on the river.

Over One Ton of PCBs Removed from River

Over the two years the project was operational, 2,111 pounds of PCBs were removed from the river. "As a result of this project, over a ton of PCBs have permanently been removed from the river and the ecosystem," said Bruce Baker, DNR Fox River Project team leader. "This project clearly demonstrates that a safe and effective cleanup of the river can be accomplished when an appropriate remedial option is selected and implemented efficiently."

In May, Fort James, DNR, and the U.S. Environmental Protection Agency (EPA) signed an Administrative Order of Consent in which the company agreed to remove contaminated sediment from the site. The order required the project to begin by late August and finish by late November. However, because the contractor, Sevenson Environmental Services of Niagara Falls, NY, worked under an aggressive schedule, the project was started and completed earlier than expected. Dredging and dewatering operations ran 24 hours per day, seven days a week, over 69 days in order to accomplish the project goals before the onset of cold weather.

During the course of the dredging, which began on August 23, an average of 723 CYs per day of contaminated sediment were removed from the river. The highest daily production rate occurred on October 20 when 1,599 CYs were removed. The highest weekly production rate achieved was 1,265 CYs per day. This occurred during the week of October 15 to 21.

Cleanup Objectives Met

The objectives for the SMU 56/57 project called for the removal of a specific volume of contaminated sediment from an area established in the original pilot project. The objectives of the work performed this year called for the area to be dredged to a specific elevation. The remaining sediment was then sampled. Areas with PCB concentrations less than 1ppm were considered to be completed, and needed no further work. Areas with PCB concentrations between 1 and 10ppm were to be covered with at least a six-inch layer of sand. If confirmation sampling showed levels above 10ppm, the dredging was to continue until the PCB concentration in the surface sediment was below 10ppm.

All the cleanup objects were met for this project. Confirmation samples taken from the site ranged from "no detect" to 9.5 ppm. Eleven out of 28 samples (about 40%) were less than 1 ppm and 24 of the 28 samples (86%) were below 4 ppm. Please note that all analytical results are preliminary. Completion of Quality Assurance and Quality Control of this data is expected by early January, 2001. Since this project was classified as an emergency response action, the cleanup objectives were specific for this project, and are not indicative of what the objectives would be for a cleanup of the entire river

The agreement between Ft. James Corporation, DNR, and the EPA called for the company to be released from further liability, in the dredged area, if the cleanup objectives were met.

9 to 12 inches Sand Cover Placed Over Entire Site

Ft. James Corporation chose to cover the entire dredged area with sand to further reduce exposure to PCBs. This also makes it easier to determine exactly which areas were dredged. The sand covering on most of the 6 ½ acre dredged area ranged from 9 to 12 inches, and thicker in some sections. This helped to cover any exposed PCBs left in the surface sediment and in the side slopes along the edges of the dredged area.

Over 55,000 tons, of Dewatered Sediment Transported to the Landfill

The dredged sediment was piped to an onshore dewatering operation at a site adjacent to the Fort James mill. There, the sediment was separated from the water and trucked off to a waste disposal landfill, owned and operated by Fort James near Austin Straubel International Airport in Ashwaubenon. The dredging operation included a 2,400 gallon-per-minute water treatment system, and a de-watering structure set up to "squeeze" water from the contaminated sediment. A total of over 55,000 tons, or 2,500 truckloads, of de-watered sediment were transported to the landfill during the project.

66 Million Gallons of Treated Wastewater Returned to the River

Over 66 million gallons of treated river water were returned to the river. The water was filtered through a series of sand, cloth, and carbon filters before entering the river. The discharged water showed no detectable levels of PCBs or mercury. As part of the decontamination and demobilization activities, all the used silt curtain, filter sand, and carbon and bag filters were placed in the landfill, which was then covered.