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ST. LOUIS COUNTY
ST. LOUIS COUNTY
Congressional District # 08
ST. LOUIS RIVER SITE
EPA ID# MND039045430Last Updated: April, 2008
Site Description
The St. Louis River site comprises two state Superfund (MERLA-Minnesota Environmental Response and Liability Act) listed sites: St. Louis River/Interlake/Duluth Tar (SLRIDT) and US Steel (USS). In 1983, the United States Environmental Protection Agency (U.S. EPA) consolidated the SLRIDT site and the USS site and added them to the National Priorities List (NPL), the federal Superfund list, as one site: the St. Louis River/Interlake/U.S. Steel site with a hazard ranking score of 32. In 1984, Minnesota Pollution Control Agency (MPCA) added both sites to the state's Permanent List of Priorities (PLP).
Both sites have separate project teams, are in different phases of remediation, and have different potentially responsible parties (PRPs).The sites are located upriver from Lake Superior, i.e., SLRIDT is four miles from Lake Superior and USS sites are eight miles from Lake Superior. Approximately 800 people live within one mile of the site. Contaminated groundwater is not used as a drinking water source. Drinking water is supplied from an intake, several miles into Lake Superior.
SLRIDT Site
The SLRIDT site is within the West Duluth neighborhood in the city of Duluth, St. Louis County, Minnesota. The site is located on the north bank of the St. Louis River, approximately four miles upstream from Lake Superior, and encompasses about 255 acres of land and river embayments, wetlands, and boat slips. The land portion of the site includes the 59th Avenue Peninsula (Hallett Peninsula), the 54th Avenue Peninsula, and is bounded on the north by the Burlington Northern right-of-way. The aquatic portion of the SLRIDT site includes Stryker Embayment (approximately 35 acres and defines the western boundary), Boat Slip 6 (about 23 acres), and Keene Creek Bay / Boat Slip 7 (about 27 acres and defines the eastern boundary), and is bounded on the south by the St. Louis River. Stryker Embayment is a shallow water embayment with emergent wetlands at the north end of the embayment. Boat Slip 6 is a deep-water environment, used for loading and unloading ships. Keene Creek Bay/Boat Slip 7 is emergent wetlands and a shallow water environment, grading into a deep-water environment.
The upland portion of the site is zoned for industrial use. Residences are located west of the SLRIDT site on the 63rd Avenue Peninsula and to the north of the railroad tracks. Approximately 800 persons live within one mile of the site. A walking trail and boat docks are along the western bank of the Stryker Embayment, and some residents have been known to swim and fish in the embayment, despite repeated warnings not to do so. A "No Swimming" sign has been posted along the walking trail. A campground, a school, a community center, and a school play field are located within one mile of the SLRIDT site's boundaries.
The SLRIDT site is the former location of pig iron and coking plants and a water/gas plant that began operation in 1904. Tar and chemical companies used byproducts of the iron companies' coking operations to make other products, including tar paper and shingles. The tar and chemical companies closed operations in 1948. The iron plant closed its operations in 1961 and toppled the blast furnace and emptied the coke ovens in 1962.
Beginning in 1979, MPCA documented that as a result of past industrial operations and disposal activities, conducted by the PRPs, soil, groundwater, and sediments on and beneath the SLRIDT site are contaminated with tar, polycyclic aromatic hydrocarbons (PAHs), volatile organic hydrocarbons (VOCs), cyanide, naphthalene, and heavy metals, including mercury.
In 1991 and 1993, MPCA identified four PRPs. These include the Interlake Corporation (Interlake, now known as GKN North America Services and referred to as the XIK Corporation), Allied Signal Inc., (Allied, now known as Honeywell International Inc.), Domtar Inc., (Domtar), and Beazer East Inc., (Beazer).
USS Site
The US Steel Duluth Works (USS ) site is located near a residential neighborhood, Morgan Park, and a light industrial area in the far western area of Duluth, Minnesota. The site includes 500 acres of land and 80 acres of sediment. It operated as a steel mill and coke production facility from 1915 until 1979, making steel products such as nails, wire, and steel sign posts. Contaminants of concern are primarily PAHs, SVOCs, and heavy metals. Other contaminants such as PCB and dioxins/furans have also been found on land and in the sediments. Contamination was found in the soil, groundwater, surface water, and sediments. The PRP is US Steel and is actively remediating the site.
Site Responsibility
This site is part of U.S. EPA Deferral Pilot Project and was placed under MPCA's jurisdiction in 1995. The MPCA has been overseeing a PRP group in Remedial Investigation/Feasibility Study (RI/FS) and Remedial Design/Remedial Action (RD/RA) activities at the SLIDRT portion of the Site and the MPCA has been overseeing US Steel as the PRP at the USS portion of the Site.Threats and Contaminants
Near the site the St. Louis River is an estuary with some industrial and residential uses but also a large area of natural river system. Abundant wildlife and productive fisheries are present. The State of Minnesota has issued a fish consumption advisory for area fish for mercury. As directed by MPCA the PRPs have posted “no sediment contact” warning signs, discouraging direct sediment contact in the site areas.
SLRIDT Site:
In 1979, PAHs were detected in Stryker Embayment sediments by MPCA staff. Subsequent analysis of samples of embayment surface water by MPCA staff in 1980, showed the presence of PAH compounds. In addition, in 1981, a local resident reported oil rising to the surface of Stryker Embayment, apparently from the slow release of oil from the sediments. Subsequent investigations have revealed significant PAH, heavy metals, and mercury contamination in the SLRIDT site sediments. The contamination on the land portion of the SLRIDT site was found as tar seeping at the ground surface, tar deposits within the fill material, tar-impacted soil and fill, solid wastes such as coal and coke particles, ash, slag, and clinker. MPCA has documented that as a result of past industrial operations and disposal activities conducted by the PRPs, soil, groundwater, and sediments on and beneath the SLRIDT site are contaminated with tar, PAHs, VOCs, cyanide, naphthalene, and heavy metals, including mercury.
USS Site:
Spills or disposal of coking coal tar byproducts and byproducts of coal tar refining resulted in semi-VOCs, PAHs, and metal contamination of soils, shallow groundwater, surface water, and sediments. The Coke Settling Basin was constructed within a creek bed and direct discharge was allowed to fill in many acres of former water body areas. The Wire Mill pond also took direct discharge from the wire production and has shown to extend out into the river sediments.
Cleanup Progress
The SLRIDT site was split up into these three Operable Units:
Tar Seeps Operable Unit (TSOU, U.S. EPA OU01)
Soil Operable Unit (SOU, U.S. EPA OU03)
Sediment Operable Unit (SedOU, U.S. EPA OU04).
Actions to Date on SLIDRT Site
TSOU (EPA OU01) and SOU (EPA OU03) Remedy
Contamination of the TSOU and the SOU consisted of tar seeping at the ground surface, tar deposits within fill material, tar impacted soil and fill, solid wastes such as coal and coke particles, ash, slag, and clinker. On March 26, 1991, the MPCA Citizens' Board (Board) issued a request for response action (RFRA), pursuant to MERLA, Minn. Stat. ch. 115B, to: Allied, Domtar, and Interlake for the implementation of the selected remedy for the TSOU, further investigation of the SOU, and implementation of the selected remedy for the SOU. U.S. EPA and MPCA had previously issued a record of decision (ROD) for the TSOU on September 28, 1990. In September 1992, Allied, Domtar, and Interlake initiated the selected remedy for the TSOU. The selected remedy, completed in March 1994, included excavation of the tar seep wastes and transportation of the wastes to be burned offsite for energy recovery at the Missouri Fuel Recycler / Continental Cement Company of Hannibal, Missouri
On May 25, 1993, the Board issued a RFRA to Interlake for additional areas of soil contamination to become an integral part of the SOU and to Beazer for the TSOU and the SOU. On September 26, 1995, the MPCA Board issued a ROD to Allied, Beazer, Domtar, and Interlake for the SOU. The major components of the selected remedy, completed in October 1997 by the PRPs, included excavation of contaminated soil, thermal desorption, and landfilling. Because the current and future land use of the upland portion of the site is industrial, remedial actions included cleaning up the site to accommodate an industrial setting. As a result, property use restrictions were to be developed by MPCA and the landowner and were to be filed with the property records.
Although groundwater at the SLRIDT site has been impacted by soil contamination, it's not currently used as a source of drinking water. However, groundwater does discharge to surface water and is being evaluated as part of the SedOU.
SedOU (EPA OU04) Remedy at SLRDT portion of the Site
MPCA signed a ROD for the Sediment Operable Unit of the SLRIDT portion of the Site in August of 2004. The ROD identified a Revised Dredge/Cap Hybrid Alternative as the selected remedy. The main components of the remedy consist of dredging approximately 224,000 cubic yards of contaminated sediments and placing them in a containment facility constructed in a boat slip on site; capping approximately 28 acres; and capping approximately 11 acres of contaminated sediments with the highest naphthalene concentrations using surcharging techniques. The surcharge technique will be used to consolidate the underlying sediment and isolate contaminants without reducing water depth and natural resource functions.
Response actions to the sediment contamination began in 2006, and consisted of the construction of the Confined Aquatic Disposal (CAD) facility in Slip 6, and construction of a 2000 foot sheet pile wall to create the capping and surcharge containment structure for an 11 acre surcharge cap in Stryker Bay.
2007 remedial activities consisted of construction of an on-site waste water treatment plant, on-going dredging of approximately 125,000 cubic yards of contaminated sediment from Stryker Bay and placing it in the Slip 6 CAD with a slurry pipe, and excavation of two contaminated wetland areas on the 54th Avenue Peninsula.
2008 remedial activities will consist of placement of cover sand and armor material in Stryker Bay, completion of the 54th avenue wetland excavations and placement of covers, dredging of contaminated sediments located in the Federal Navigation Channel and waters of the state of Wisconsin (south of CAD end dike in Slip 6 and MN Channel Dredging), and completion of Slip 7 capping, cover, and armoring. Additionally, Stryker Bay Cap/Surcharge will continue to settle.
2009 and 2010 remedial activities are expected to consist of the removal of the temporary sheet pile containment wall from Stryker Bay Cap/Surcharge Area, removal of the surcharge sand from Stryker Bay, installation of the CAD cover material in the former Slip 6, dredging and transportation of the environmental media from the Tallas Island mitigation project, placement of the environmental media over all of the capped and covered areas of the entire SLRIDT Site, and finally, restoration of the Tallas Island Dredge Area and final restoration of the SLRIDT Site.
During construction, air, water and noise monitoring are taking place on a regular basis.
Response actions are scheduled to be completed by the end of 2010; At least 30 years of long term monitoring and O&M will then begin.
US Steel Site: Actions to Date
The USS Site has 18 “sub” operable units as defined in the 1989 ROD, OUA-OUR, and 16 remedies are completed; the two remaining are sediment OUs. Two OUs were completed in 1997 that left coal tar wastes in place at levels above the unrestricted use standards. These are OUJ, the coke settling basin and the OUP, and Wire Mill Pond. Seven of the OUs were designated as “No Action” which includes long-term monitoring. Action at seven other OUs was contamination removal or capping.
OUP Remedy
The Wire Mill Pond received wastewater from the wire mill and other USX operations. The pond contained several feet of oily waste as well as PAH, PCB, VOC, cyanide, and heavy metals. Contaminant level pond water exceeded surface water quality standards.
A response action plan was submitted to MPCA in March 1996 and approved by MPCA in November 1996. Response actions began in June 1997 and were completed in December 1997. In all 6,487 tons of sediments, containing high levels of oils and grease, PAHs and metals, were removed and transported to an industrial waste landfill. The remaining contamination in the pond was covered and lined with geotextile fabric, backfilled with clean sand, and planted with native wetland vegetation. Performance surface water monitoring of the outfall continues on a semiannual basis. No significant exceedences of performance criteria have been detected to date.
OUJ Remedy
USS retained Geraghty & Miller, Inc. to re-evaluate four alternatives for Operable Unit J, including a slurry wall containment system, a
slurry wall system with in-situ treatment, in-situ cement stabilization, and a funnel and gate system. A response action plan (RAP) for Operable Unit J was submitted to MPCA in March 1996, proposed in-situ cement stabilization as the preferred remedy, and approved the RAP in November 1996. Field work began in June 1997 and was completed in December 1997. Approximately 10,000 cubic yards of coal tar and tar-contaminated soil were solidified in-place and a seven-foot-engineered cap was placed over the unit and vegetated. Semiannual surface water monitoring of the Unnamed Creek that flows around OUJ continues and is used as the performance criteria. Monitoring to date has shown no exceedences of surface water quality performance criteria.
As the OUs were completed, site buildings were dismantled as part of the site closure and incorporated in an onsite demolition landfill. Two demolition landfills are present on site.
Currently, a remedial investigation is ongoing for the two sediment operable units. The original remedy was identified in the ROD as "No Action", working under the theory that natural deposition at the site will adequately cap the contamination. A sediment survey in 1993 noted that natural sedimentation is not adequate, and contamination is exposed at the surface in some locations. Sampling in 2003 was conducted to confirm the magnitude and extent of contamination with a human health and ecological risk assessment to be completed in 2008. Another sediment “area” noted in the ROD was the “Area In-between (but not included) OUI and OUJ”. The remedy for this area was a removal of coal tar product for use as fuel. It was not clear in any of the past actions that this area was removed. Since 2003, this area has been inspected over the summer and the creek is impacted by tar balls and sheens. Further investigation of this sediment area will be included with the River sediment units.
As a result of the 5-Year Review (discussed below), additional investigations are currently underway. It is expected that these investigations will be completed by 2012 after which MPCA will determine a cleanup remedy.
Results of the 2008 Five Year Review by Minnesota Pollution Control Agency (MPCA)
U.S. Steel Site
The 1989 Record of Decision (ROD) for the USS Site identified 18 separate OUs and two additional areas of concern. Three additional areas of concern were identified since issuance of the ROD which are included in this Five-Year Review. The results of this Five-Year Review
indicate that, although the RAs have contributed to a decrease in risk to human health and the environment, contamination remains in soil, sediment, and surface water exceeding regulatory criteria. In addition, migration of contaminants from the OUs to the St. Louis River, an
Outstanding International Resource Water (OIRW), is occurring.
With the exception of OU-N and OU-R, a protectiveness statement was developed for each OU and additional areas of concern that remains at the site. Protectiveness statements were not developed for OU-N and OU-R because these areas are being evaluated as a component of an ongoing river sediment investigation. Although protectiveness statements were developed, a site-wide risk evaluation and establishment of institutional controls for all OUs and areas of concern that remain on-site are required in order to provide complete short-term and long-term protectiveness statements.
Several issues have been raised with respect to the current land use, along with new Applicable, Relevant, and Appropriate Requirements (ARARs), and To Be Considereds (TBCs) including the following:
• There were no Target Clean-up Levels (TCLs) developed for soil in the 1989 ROD. The First Five-Year Review did present potential TBCs for a few Contaminants of Concern (COCs) based on the MPCA SRVs. TCLs will be developed for all COCs.
• The TCLs for surface water delineated in the 1989 ROD were updated in 1997. It is unknown if these criteria include all surface water ARARs, including OIRW criteria and standards.
As a result of these concerns, the MPCA is in the process of reviewing the exposure assumptions, toxicity data, and cleanup levels for all media at the site. Several OUs and areas of concern are not considered protective in the short-term for the following reasons:
• Thirteen separate areas of tar and tar-contaminated soil (OU-A) were noted across the site. These areas clearly show that the RAs for OU-A have not been completed as intended by the ROD.
• Oil sheens were observed in the Area Between OU-I and OU-J, OU-P, OU-Q, and “Dog Pond”. In accordance with Minn. Rules ch. 7050.0210 Subp. 2, oil sheens are prohibited.
• Analytical results of soil, water, and/or sediments indicate the presence of contamination above screening criteria in the Area Between OU-I and OU-J, OU-L, OU-Q, Crushed Slag Disposal and High pH Area, and “Dog Pond”.
• Natural disturbances to the OUs include beaver activity, flooding, and erosion of delta sediments in OU-J, OU-L, and OU-M.
In addition to a risk evaluation and institutional controls, in order to assure the long-term protectiveness of the site, several remedial areas will have additional follow-up activities, including:
• Repair OU-J cover. Erosion and settlement/slumping of the cover and gabion walls of OU-J containment cell is occurring and must be corrected/repaired. A perimeter fence will be installed to restrict access to the cover.
• Repair and Maintain OU-K cover. Damage to the soil cover from trespassers and off-road vehicle use will be repaired. A perimeter fence is recommended to restrict access to the cover. Annual inspection and maintenance including tree/shrub removal must be conducted.
• Investigate the source of the oil sheens in OU-P. The protectiveness of the cover will be evaluated. If it is determined that the cover is not protective, additional actions will be implemented.
• Develop and implement a revised inspection and monitoring program. An updated annual site inspection and monitoring program will be developed that addresses all media of concern. The monitoring program will be developed and implemented undated in conjunction with a site-wide risk evaluation. The monitoring program will also include an operation and maintenance plan that addresses: trespassing (site access, warning signs, fencing); semi-annual sampling; semi-annual site inspections including inspecting OUs and cap and cover inspection and maintenance.
The remedy at the USS Site cannot be determined for protectiveness at this time. Further information will be obtained and evaluations will be performed as described in this Report. Additional actions will also be undertaken at OU-N and OU-R.
St. Louis River/Interlake/Duluth Tar Site
The SLRIDT Site has three OUs: the TSOU; the SOU; and the Sediment OU (SedOU). Remedial actions have been completed at the TSOU and the SOU. A remedy was selected for the SedOU in 2004 and is currently being implemented.
The result of this Five-Year Review indicates the TSOU remedy is protective of human health and the environment. The tar seeps identified in the TSOU ROD were location-specific and have been removed.
The First Five-Year Review indicated the SOU remedy is protective of human health and the environment in the short-term as the RAs identified in the ROD have been completed. However, this Five-Year Review identified several issues that must be addressed before a final
protectiveness statement for the SOU can be made including:
• A tar layer was discovered near the radio tower on the west side of Stryker Bay. Further evaluation will be conducted. Additional remedial actions will be taken if this evaluation indicates that they are required to provide a fully protective remedy.
• Residual Operational Material in Area E. Open pits or former storage vessels containing water/waste or that are filled in with soil were observed within the on-site buildings. These pits or former storage vessels may contain tar and/or tar-impacted soil. Operational waste
that was left behind could be a continued source of soil and groundwater contamination and should have been included in the SOU. Further evaluation will be conducted. Additional remedial actions will be taken if this evaluation indicates that they are required to provide a
fully protective remedy.
• Oil Sheen near Area E storm sewer outfall. The oil sheen observed in this area indicates that there may be a source of contamination remaining. Further evaluation will be conducted. Additional remedial actions will be taken if this evaluation indicates that they are
required to provide a fully protective remedy.
In order to assure the long-term protectiveness and develop a long-term protectiveness statement, the following issues must be addressed:
• Update risk evaluation. Perform additional evaluation of risk (soil) based on current screening criteria and contaminant migration of soil vapor to indoor air.
• Develop or revise restrictive covenants for all property owners.
• Enforce institutional controls.
A comprehensive SLRIDT site-wide protectiveness statement cannot be developed until the issues of this Second Five-Year Review are addressed and the SedOU remedy is completed.
U. S. Steel and SLRIDT Overall Protectiveness Statement
A comprehensive site-wide protectiveness statement cannot be made until further information is obtained and the recommendations contained within this Second Five-Year Review Report are implemented. Additionally, upon completion of further evaluations, other remedial actions will also be selected for OU-N and OU-R at USS and construction completed for the SedOU at SLRIDT. It is expected that these actions will take approximately 5 years to complete, at which time a protectiveness determination will be made.
Community Involvement
Monthly Community Work group Meetings are held on each second Wednesday of the month during the construction season.Property Reuse
US Steel Duluth Works: Conceptual Reuse Framework
Based on stakeholder group discussions and meetings, as well as on analyses of the site’s physical characteristics, contamination and remediation options, land use and market conditions in the City of Duluth and surrounding St. Louis County, the project’s consultant team worked with project stakeholders to develop a site reuse strategy, called a Conceptual Reuse Framework. The results are called a “framework” because they represent an early plan that is a flexible structure able to incorporate additional detail and information as the site’s remedy is designed and implemented. The remediation of Superfund sites like the US Steel Duluth Works site can take years, rather than months, so plans for the site’s future use must be flexible enough to incorporate new information over time. The framework is also designed to allow for portions of the site to be adapted for reuse in different phases so that site reuses can benefi t the community as soon as possible. For instance, the site could initially begin serving the neighboring communities as an ecological and recreational amenity. During this phase of reintegrating the site into the community, planning for the second phase could begin which could include community oriented facilities as well as mixed commercial and residential development. The following sections describe the potential amenities of the Framework in greater detail. Ecological and Recreational Amenities The US Steel Duluth Works site could serve as a significant ecological and recreational amenity for future site users, visitors, and residents of the surrounding neighborhoods. The eastern portion of the US Steel Duluth Works site offers extensive views of the St. Louis River, potential for waterfront access, and a perennial stream corridor. Wetland areas adjacent to the St. Louis River provide excellent natural habitat and opportunities for wildlife viewing for new neighborhood residents. The site also features a historic tourist train, operated by the Lake Superior and Mississippi Railroad Company, which runs along tracks parallel to the St. Louis River during non-winter months. The US Steel Duluth Works site is located within one mile of three neighborhood parks, regional Bardons Peak Forest Park, and biking and walking trails like the Western Waterfront Trail, Iron Trail, and the Munger Trail. The region’s network of biking and walking trails serve as a local and regional attraction for Duluth and are also a nationally-recognized bird-watching resource. Species including the harlequin duck, black-capped chickadee, downy woodpecker, red-breasted nuthatch, white-winged crossbilll and great gray owl can be found in the area. During winter months, snowshoeing and cross-country skiing along Duluth’s established trails is a popular way to view birds and other wildlife such as deer, red fox, and timber wolf.
Contacts
Remedial Project Manager, U.S. EPAjames hahnenberg (hahnenberg.james@epa.gov)
(312) 353-4213
Community Involvement Coordinator, U.S. EPA
dave novak
(312) 886-7478
Aliases
ST LOUIS RIVERINTERLAKE/DULUTH TAR
ST LOUIS RIVER HAZ WASTE SITE
US STEEL CORP DULUTH WKS