Sheboygan River dredging scheduled to start in April

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Sheboygan River dredging scheduled to start in April

By Dan Benson • For Wisconsinoutdoorfun.com • March 4, 2011

Work on dredging the Sheboygan River of tainted sediments and deepening its channel nearer the harbor will be under way in April and likely will be completed by the end of 2012. Local leaders are hailing the moves as a key toward helping lift Sheboygan from its economic doldrums.

The effort "will be great for the prosperity of the City of Sheboygan," Sheboygan Mayor Bob Ryan said at the beginning of a public forum Wednesday night at the Mead Public Library attended by about 50 people, many of them city, county, state and federal officials, as well as private business leaders, who have worked on the planning for the cleanup.

"This is a true public-private partnership getting this river cleaned up," Ryan said.

The EPA declared the 14 miles of the river from Sheboygan Falls to the Sheboygan Harbor a hazardous waste site under the federal Environmental Protection Agency Superfund legislation in 1986.

About $20 million already has been spent to clean the river above Boat Island of polychlorinated biphenyls, or PCBs, cancer-causing chemicals that were widely used in hydraulic fluids, coolants and lubricants. Manufacture of PCBs was halted in 1977. The Tecumseh plant in Sheboygan Falls has been identified as a major source of PCBs in the Sheboygan River.

In all, more than 100,000 cubic yards of contaminated river sediment will be removed over the next two years, lowering the riverbed an average of 3 to 4 feet between the Eighth Street bridge and the area of the river around Boat Island and the 1.5-acre former Campmarina manufactured gas plant on the north bank of the river at 732 N. Water St. A city-owned park is there now.

EPA testing showed that pollutant concentrations in the area downriver from the Eighth Street bridge aren't heavy enough to require cleanup, said Pablo Valentin, an EPA project manager helping oversee the project.

The work will be done in two phases at a total cost of about $37 million — $15 million in 2011 as part of the EPA Superfund clean-up effort, and $22 million in 2012 under the Great Lakes Legacy Act. The City of Sheboygan, Sheboygan County, state Department of Natural Resources and the Wisconsin Public Service have each contributed $100,000 toward the cleanup.

Mark Tuchman, another EPA official, admitted future funding is up in the air due to the budget debate in Washington.

"But we're optimistic they'll keep the whole thing going," Tuchman said.

Near the Campmarina site are high concentrations of another pollutant, polynuclear aromatic hydrocarbons — or PAHs — which are petroleum products that also cause cancer.

Valentin said "emergency removal" practices will be necessary to remove the PAHs because they can be suspended in water and washed downstream if disturbed.

"There is the possibility of them being dispersed in the water," Valentin told the audience.

Consequently, a steel cofferdam will be driven into the sediment on the east side of Boat Island to corral the pollutants.

"There will be a lot of pounding and noise while the cofferdam is being built," Valentin said.

Contaminated sediment will be taken to a dewatering site near 22nd Street and Maryland Avenue, where it will be treated and then transported to one of two landfills. Treated sediment with lower levels of contamination will be taken to a landfill near Chilton. Dirt with greater contamination will be taken to a specially designed landfill in Michigan. Treated water will be returned to the river.

Once the river is cleaned, officials say improvements to the river may include fish spawning areas, wildlife habitat improvements and erosion control efforts.