Sheboygan River and Harbor, WI

A.64 Sheboygan River and Harbor, WI

A.64.1 Contacts

Remedial Project Manager:
Pablo Valentin
312-353-2886 or 800-621-8431, ext. 32886
[email protected]

Community Involvement Coordinator:
Susan Pastor
312-353-1325 or 800-621-8431, ext. 31325
[email protected]

Assistant Regional Counsel:
Richard Nagle
312-353-8222 or 800-621-8431 ext. 38222
[email protected]

State of Wisconsin Technical Representative:
Thomas Wentland
920-892-8756
[email protected]

A.64.2 Summary

Environment:	Sheboygan River Western Shore of Lake Michigan
Scale:	Full
Contaminants of Concern:	Polychlorinated biphenyls (PCBs)
Source Control Achieved Prior to Remedy Selection?	Yes – upland soils and groundwater controls
Final Remedy:	Removal and MNR: Upper River removal of between 20,774 yd³ of PCB-contaminated sediment to achieve a removal of 88% of the PCB mass in the soft sediments. This would achieve a Surfaced Weighted Area Concentration (SWAC) of 0.5 parts per million (ppm) in the combined Upper and Middle River segments. Middle River no action required. Lower River removal of 16,158 yd³ of PCB-contaminated sediment to achieve soft sediment SWAC of 0.5 parts per million (ppm). Inner Harbor removal of 34,390 yd³ of PCB-contaminated sediment to achieve soft sediment SWAC of 0.5 ppm.
Expected Recovery Time:	19 years
MNR viewed as a success?	MNR is considered an element of the cleanup process

A.64.3 Site Description

Sheboygan River and Harbor, Sheboygan County, Wisconsin. CERCLIS ID: WID 980 996 367

Sheboygan River and Harbor includes the lower 14 miles of the river from the Sheboygan Fall Dam downstream and including the Inner Harbor. The site includes the Upper River, Middle River, Lower River, and Inner Harbor. This segment of the river flows through the communities of Sheboygan Falls, Kohler, and Sheboygan before entering Lake Michigan. Tecumseh was located adjacent to the Sheboygan River in Sheboygan Falls, Wisconsin. The primary sources of contamination at this site were discharges from Tecumseh Products Co., a manufacturer of refrigeration and air conditioning compressors and gasoline engines.

The United States Army Corps of Engineers (USACE) constructed the Sheboygan Harbor and navigation channels in the early 1920s and performed routine maintenance dredging activities until 1979 when sediment samples indicated moderate-to-high levels of lead, zinc, PCBs, chromium, and moderate levels of arsenic were present. PCBs were found in sewer lines that discharged from Tecumseh’s facility to the river. PCBs were also found in hydraulic fluids used in the Tecumseh Products Company’s Diecast Division manufacturing processes. Contamination was high in sediments immediately surrounding the Tecumseh plant but decreased downstream. Tecumseh performed preliminary cleanup actions in the late 1970’s following the USEPA’s issuance of PCB regulations.

In 1989 and 1990, EPA requested Tecumseh to conduction actions to remove about 5,000 yd³ of contaminated sediment which was stored in two containment facilities at Tecumseh’s Sheboygan Falls plant. In addition, approximately 1,200 square yards of highly contaminated sediment were capped or “armored” in place to prevent contaminants in the sediments from entering the river.

CSM summary: The Conceptual Site Model includes contaminated sediments in the Upper River, low levels of contaminated sediments in the Middle River, contaminated sediments in the Lower River and Inner Harbor, contaminated soils in the River Floodplain, and contaminated groundwater at Tecumseh’s Sheboygan Falls Plant.

A.64.4 Remedial Objectives

USEPA developed a sediment cleanup goal to protect human health, based on the consumption of bass under the reasonable maximum exposure scenario (RME). The goal would range from 0.005 ppm which equals a 1 in a million risk to 0.5 ppm which would equal a 1 in ten thousand risk. The 10^-6, or 1 in a million, risk level is the departure point for managing site risks.

Based on the NOAA Aquatic Risk Assessment, PCB-contaminated sediment pose a risk to fish and wildlife, U.S. EPA analyzed the ecological risk, in consultation with the natural resource trustees. A sediment cleanup goal between 0.05 ppm and 1.0 was determined to protect fish and wildlife. The 0.05 ppm level represents the No Observed Adverse Effects Level (NOAEL) for the mink while the 1.0 ppm represents the Lowest Observed Adverse Effects Level (LOAEL) for the Heron.

RAOs/Project objectives: The remedy consisted of three primary RAOs:

Protect human health and the environment from imminent and substantial endangerment due to PCBs attributed to the site. To achieve this remediationThe act or process of abating, cleaning up, containing, or removing a substance (usually hazardous or infectious) from an environment. objective, PCB-contaminated soft sediment will be removed so that the entire river will reach an average PCB sediment concentration of 0.5 ppm or less over time. An average PCB sediment concentration of 0.5 ppm results in an excess human health carcinogenic risk of 1.0 x 10^-4or less over time through the consumption of PCB-contaminated fish. Based on site-specific biota to sediment accumulation factors, the corresponding PCB tissue level of resident fish are:

Sport Fish	Bottom Feeders
Small Mouth Bass: 0.31 ppm	Carp: 2.58 ppm
Walleye: 0.63 ppm	Catfish: 2.53 ppm
Trout: 0.09 ppm

For PCB-contaminated floodplain areas, this remediation objective will be achieved by removing sufficient contaminated soil to reach an average PCB soil concentration of 10 ppm or less.
Mitigate potential PCB sources to the Sheboygan River/Harbor system and reduce PCB transport within the river system.

Remove and dispose of Confined Treatment Facility/Sediment Management Facility sediments and previously armored/capped PCB-contaminated soft sediment deposits.

A.64.5 Remedial Approach

Final selected remedy: Removal and MNR

Remedy Contained in two separate documents Record of Decision (ROD) and Explanation of Significant Difference (ESD)

ROD May 2000

Upper River sediment removal of approximately 20,774 yd³ of PCB-contaminated sediment to achieve a removal of 88% of PCBs mass from soft sediment. Conduct fish and sediment sampling to document natural processes and ensure that over time the entire river will reach an average PCB sediment concentration of 0.5 ppm or less. Middle River sediment characterization combined with Upper River conditions to achieve a soft sediment SWAC of 0.5 ppm overall in the Upper and Middle River. Conduct fish and sediment sampling to document natural processes and ensure that over time the entire river will reach an average PCB sediment concentration of 0.5 ppm or less.

Lower River sediment characterization, removal of sediment if necessary to achieve a soft sediment SWAC of 0.5 ppm in the Lower River, annual bathymetryThe measurement of or the information from water depth at various places in a body of water. surveys to identify areas susceptible to scour, and fish and sediment sampling to document natural processes and ensure that over time the entire river will reach an average PCB sediment concentration of 0.5 ppm or less.

Inner Harbor sediment characterization, removal of approximately 53,000 yd³ of PCB-contaminated sediment to achieve a SWAC of 0.5 ppm in the Inner Harbor, annual bathymetry surveys to identify areas susceptible to scour, fish and sediment sampling to document natural processes and ensure that over time the entire river will reach an average PCB sediment concentration of 0.5 ppm or less.

Removal of floodplain soils containing PCB concentrations above 10 ppm. Investigation and mitigation of potential groundwater contamination and possible continuing sources at the former Tecumseh Plant in Sheboygan Falls. Placement of institutional controlsNon-engineered instruments, such as administrative and legal controls, that help minimize the potential for human exposure to contamination and/or protect the integrity of the remedy. (ICs) to limit access to Tecumseh's Sheboygan Falls Plant groundwater as a drinking water source.

Explanation of Significant Difference (ESD) December 2010

The ESD adjusted the volume of contaminated sediment to be removed from the river, the areas from which those sediments will be removed and the cost of the modified remedy, as a result of the pre-design characterization effort and remedial design for the Lower River and Inner Harbor portion of the remedy.

This modification to the selected remedy set forth in the ROD does not fundamentally alter the basic features of the selected remedy with respect to scope, performance, or cost. The modification provides for the implementation of the remedy for the Lower River and Inner Harbor at the Site in a way that will address the most contaminated PCB soft sediment vulnerable to recreational and natural disturbances in order to achieve the 0.5 ppm SWAC in both reaches over time. Consistent with the Remedial Investigation, a soft sediment deposit shall be defined as an area containing a soft sediment depth of 1 ft or greater as determined by probing.

	May 2000 ROD Contaminated Sediment Volume to be Removed	Lower River Remedial Design Contaminated Sediment Volume to be Removed
Lower River	None	16,158 yd³
Inner Harbor	53,000 yd³	34,390 yd³
Total Volume of Contaminated Sediment to be Removed from the Lower River and Inner Harbor	50,548 yd³

May 2000 ROD

Contaminated Sediment

Volume to be Removed

Lower River Remedial Design

Contaminated Sediment Volume to be Removed

Lower River

None

16,158 yd³

Inner Harbor

53,000 yd³

34,390 yd³

Total Volume of Contaminated Sediment to be Removed from the Lower River and Inner Harbor

50,548 yd³

Advantages of the selected remedy:

Permanent, long term solution
Mass removal of PCBs

Disadvantages of the selected remedy:

PCBs will still be available at sediment/water interface for fish to bioaccumulate
Fish tissue concentrations will require lengthy recovery timeline
Remedy is complex

Expected recovery time: 19 years.

A.64.6 Monitoring

Monitoring elements: Monitoring will occur under the 5 year review which will take place within 1-2 years. No plan has been designed yet.

RAOs/project objectives achieved: Upper River mass removal at 88% was achieved. Sediment removal is ongoing in other portions of the river and harbor.

A.64.7 Costs

Net present value for project costs: Upper River $23,800,000; Lower River and Inner Harbor $10,000,000; Floodplain soil $4,500,000; and Groundwater investigations and source controlThose efforts that are taken to eliminate or reduce, to the extent practicable, the release of COCs from direct and indirect ongoing sources to the aquatic system being evaluated. $600,000 (discounted by 7 percent per year for the estimated life of the project)

A.64.8 References

Declaration for the Record of Decision Sheboygan River and Harbor. http://www.epa.gov/region05/cleanup/sheboygan/pdfs/sheboygan_rod_200005.pdf.

Consent Decree for the Lower River Work on the Sheboygan River. http://www.epa.gov/region05/cleanup/sheboygan/pdfs/sheboygan_cd_2011.pdf.

Administrative Order on Consent for Remedial Design for the Lower River Portions of the Rod. http://www.epa.gov/region05/cleanup/sheboygan/pdfs/sheboygan_aoc_200902.pdf.

Explanation of Significant Differences. http://www.epa.gov/Region5/cleanup/sheboygan/pdfs/sheboygan_esd_201012.pdf.

Publication Date: August 2014

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