LOCATION AND PHYSICAL DESCRIPTION
Waukegan Harbor is situated in Lake County, Illinois on the western shore of Lake Michigan. Constructed by filling a natural inlet and portions of adjacent wetlands, Waukegan Harbor has water depths varying from 4.0 to 6.5 m. The harbor sediment is composed of soft organic silt (muck) which lies over medium dense, fine to coarse sand.
In 1990, approximately 75 commercial ship dockings were present in the Harbor. The majority of the materials brought through the Harbor were building/construction materials for nearby Chicago industries (Hey and Associates 1993).
Although substantial recreational use occurs in the area around the harbor, land use in the Waukegan Harbor area is primarily industrial. Of the major facilities present, the Outboard Marine Corporation (OMC) was identified as the primary source of PCB contamination in Harbor sediments. In 1972 OMC dismantled a coke oven gas plant (previously built and owned by the North Shore Coke and Chemical Company) to construct their own facilities for manufacturing recreational marine products. U.S. Environmental Protection Agency (EPA) investigations in 1976 revealed high levels of polychlorinated biphenyls (PCBs) in Waukegan Harbor sediments and in soil close to OMC outfalls. Concurrently, high levels of PCBs (above the U.S. Food and Drug Administration action levels of 2.0 ppm PCB) were also found in resident fish species. As a result, in 1981, the U.S. EPA formally recommended that no fish from Waukegan Harbor be consumed. Subsequently, the Lake County Health Department posted signs warning residents that consumption of fish from the northern Harbor could be dangerous to human health.
PROJECT GOALS AND OBJECTIVES
With the discovery of Waukegan Harbor's PCB problem in 1976, the U.S. EPA and Illinois EPA became involved in a lengthy litigation process with OMC and, as a result of the requirements of the 1980 Comprehensive Environmental Response Compensation and Liability Act (Superfund), and its 1986 Amendments, a Consent Decree was entered by the U.S. Justice Department in District Court in 1989. The Consent Decree called for remediation of the contaminated sediments greater than 50 ppm PCBs.
SEVERITY AND GEOGRAPHIC EXTENT OF PROBLEM
Early investigations of harbor sediment indicated that approximately 136,000 kg of PCBs were in the harbor proper (IJC 1989). In the most highly contaminated areas of the harbor (Slip #3), PCB concentrations in sediments were as high as 500,000 mg/kg (Figure 1). Severely contaminated areas totaled about 19 ha, including the Upper Harbor, Slip #3 and land on the northern edge of OMCs property (IJC 1987).
Figure 1. OMC site before remedial action (U.S. EPA 1988)
DESCRIPTION OF REMEDIAL ACTIONS
Remedial efforts in the Harbor began in 1990 with harbor dredging conducted in 1992. As a result of the Consent Decree, OMC provided approximately $20-25 million for remediation which included the construction of three containment cells (Figure 2). 24,500 m3 of PCB contaminated sediment was removed from the Harbor using a hydraulic dredge. Approximately 2,000 m3 of PCB-contaminated sediment, in excess of 500 mg/kg PCBs, was removed from Slip #3 (a "hot spot" that accounts for the majority of the PCBs on the site) and thermally extracted onsite to at least 97% (Taciuk Process). 11,521,400 kg of material were treated and 132,500 litres of PCBs were extracted and taken off site for destruction. The treated sediment was placed in one of the OMC containment cells. Upper harbor sediment was dredged and put in the Slip #3 containment cell. Soils in excess of 10,000 mg/kg of PCBs were also excavated and treated onsite by thermal extraction (Hartig and Zarull 1991).
Figure 2. OMC site after remedial action completed (U.S. EPA 1988)
Extracted PCBs were transported to an offsite facility for high-temperature combustion (>2200oF) in accordance with the U.S. Toxic Substances Control Act. No soils or sediments that exceeded 50 mg/kg PCBs remained onsite, except those within the containment cells.
Following completion of the soil and sediment remediation, the cells were closed and capped with a high density polyurethane liner and a soil cover (Figure 3). Extraction wells in each cell maintain an inward hydraulic gradient, to prevent PCB migration. The cells are operated and maintained by OMC. To offset the loss of slip #3, a new slip (#4) was dredged and opened to the public in July 1991.
Figure 3. Containment cell cross section (U.S. EPA 1988)
Under the Consent Decree, the Outboard Marine Corporation paid an estimated $20-25 million for remedial actions they conducted under the 1989 consent decree.
OMC was required to comply with the 1989 Consent Decree and all Superfund requirements. In addition, extracted PCBs had to be transported and incinerated in accordance with requirements of the U.S. Toxic Substances Control Act.
CLEANUP TARGETS AND ENDPOINTS
The primary cleanup target was the removal, containment, and treatment of contaminated sediments in and around the OMC property in order to meet the 50 mg/kg PCB determined under the consent decree.
POST PROJECT EVALUATION OF EFFECTIVENESS
Fish flesh sampling, conducted after the inner harbor was dredged in 1992, through the Superfund remediation in 1993 shows a substantial decrease for PCB concentrations in carp fillets. Figure 4 presents trend data for PCBs in Waukegan Harbor carp fillets (Clark 1997). PCB levels in 1993 fish show that dredging did not cause significant PCB suspension. Contaminant levels in 1993 fish averaged 5 fold lower than those tested in 1983 and 1991.
Historical information on PCB levels in fish is limited and not standardized for trend analysis. However, a review of the available data, although not subject to statistical analysis, supports the overall trend of decreasing PCB contamination of fish following sediment remediation (Table 1).
As a result of the dramatic decline in PCBs in fish, the posted Waukegan Harbor fish advisories were removed, although fish advisories still exist for carp and other harbor fish. The Illinois Lake Michigan Lakewide Advisory is protective of human health as PCB concentrations in Waukegan Harbor fish are considered to approximate fish found elsewhere in Lake Michigan.
Approximately 136,000 kg of PCBs were removed through the Superfund action. Sediment sampling indicates that about 900 kg of PCB-contaminated sediment remains in the navigational channel of the harbor. This PCB contamination and silting has resulted in cargo carrier restrictions on ships passing into the channel. The Department of Transportation has observed disturbance of navigational sediments by prop wash. U.S. Army Corps of Engineers, working with the Waukegan Port Authority, plans to remove those sediments interfering with navigation. Once completed, this action will eliminate the majority of the 900 kg of PCBs still present in harbor sediments.
CONTACT PERSONS OR AGENCIES
Waukegan Harbor RAP Co-Coordinator
Illinois Environmental Protection Agency
1021 North Grand Avenue East
P.O. Box 19276
Springfield, IL 62794-9276
Waukegan Hab RAP Co-Coordinator
Illinois Environmental Protection Agency
1701 First Avenue
Clark, J. Milton. 1997. "Policy Implications" - a presentation to the Great Lakes Roundtable - "Achieving the Future". Niagara-on-the-Lake. October 31.
Hartig, J.H. and M.A. Zarull. 1991. Methods of Restoring Degraded Areas in the Great Lakes. Reviews of Environmental Contamination and Toxicology. 117:127-154.
Hey and Associates. 1993. Waukegan Remedial Action Plan - Stage 1 Final Report. Libertyville, Illinois. 106 pp. + appendices.
International Joint Commission. 1989. Progress in developing and implementing remedial action plans for Areas of Concern in the Great Lakes Basin - Appendix A. Great Lakes Water Quality Board. Windsor, Ontario. 196 pp.
International Joint Commission. 1987. Report on Great Lakes Water Quality, Great Lakes Water Quality Board. Windsor, Ontario. 236 pp.
International Joint Commission. 1983. Report on Great Lakes Water Quality - Appendix A - Areas of Concern in the Great Lakes Basin: 1983 Update of Class 'A' Areas. Great Lakes Water Quality Board. Windsor, Ontario. 113 pp.
U.S. EPA. 1988. Cleanup of Outboard Marine Corporation/Waukegan Harbor Site. Office of Public Affairs. Chicago, Illinois. 8 pp.
Table 1 - Qualitative comparison of PCB levels in Waukegan fish
|Description of Sample||Reference or Source|
|white sucker||3.6||whole||U.S. EPA|
|white sucker||26.8||whole||U.S. EPA|
|white sucker||0.26||whole||Illinois EPA|
|white sucker||0.37||whole||Illinois EPA|
|white sucker||0.52||whole||Illinois EPA|
|white sucker||0.17||fillet||Illinois EPA|
|white sucker||0.36||whole||Illinois EPA|
|white sucker||0.86||whole||Illinois EPA|
|white sucker||0.77||whole||Illinois EPA|
|white sucker||0.90||whole||Illinois EPA|
|white sucker||0.30||whole||Illinois EPA|