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Congressional District # 14


EPA ID# ILD980823991
Last Updated: May, 2015

Site Description

The Kerr-McGee Kress Creek/West Branch of DuPage River site is one of four National Priorities List (NPL) sites in the West Chicago area that were contaminated with radioactive thorium wastes.  The radioactive waste originated from a nearby facility known as the Rare Earths Facility (REF). The REF, operated by Lindsay Light and Chemical Company and its successors from 1932 until 1973, produced non-radioactive elements known as rare earths and radioactive elements such as thorium, radium, and uranium along with gas lantern mantles for private entities and the United States government's use in federal atomic energy programs.  The REF produced these elements by extracting them from monazite sands, bastnasite (rare earth ore), and other ores, using an acid leaching process.  Production of these elements resulted in the generation of radioactive mill tailings that contained residual levels of thorium, radium, and uranium as well as certain other insoluble metals.  Kerr-McGee purchased the REF in 1967 and maintained operations until closing the facility in 1973.

At the Kress Creek/West Branch of DuPage River (KC/WBDR) site, creek and river sediments and banks and floodplain areas are contaminated with radioactive thorium wastes.  The site became contaminated when radioactively-contaminated surface runoff and discharges from the REF were carried by a storm sewer into nearby Kress Creek and, from there, downstream to the West Branch DuPage River.  The site includes approximately 1.5 miles of Kress Creek from the storm sewer outfall to the creek's confluence with the West Branch DuPage River and approximately 5.2 miles of the river from the confluence downstream to the McDowell Dam in Naperville, IL, for a total of 6.7 miles of creek and river.

Approximately 20,000 people live within three miles of the site.  Drinking water in the area is obtained from municipal or private wells and is not impacted by site contaminants.

Site Responsibility

This site was addressed through potentially responsible party (PRP) actions until January 2009, when Tronox (formerly Kerr-McGee) filed for Chapter 11 bankruptcy.  EPA successfully negotiated a settlement of environmental claims that established the West Chicago Environmental Response Trust, with Weston serving as Trustee, to complete the site cleanup. 

Threats and Contaminants

Sediments and soils at the site contained low-level radioactive contamination.  People exposed to radioactively-contaminated soils or sediments may suffer adverse health effects.

Cleanup Progress

U.S. EPA began a remedial investigation/feasibility study (RI/FS) in 1993 to determine the nature and extent of contamination at the site and to evaluate various cleanup alternatives.  Around 1997, Kerr-McGee and parties representing the affected communities asked U.S. EPA for time to negotiate an agreement and the parties eventually reached a conceptual agreement for cleanup of the site.  As part of the agreement, Kerr-McGee conducted extensive, additional characterization work at the site.  The proposed cleanup approach was contingent upon Kerr-McGee, U.S. EPA, and other governmental agencies resolving certain technical and legal issues regarding the cleanup.

In October 2003, U.S. EPA and Kerr-McGee reached an agreement in principle resolving the main outstanding technical and legal issues and signed an Administrative Order on Consent, effective November 21, 2003, for Kerr-McGee to complete the RI/FS at the site.  The order specified that Kerr-McGee would incorporate U.S. EPA's prior data as well as Kerr-McGee's extensive site characterization data into the RI and FS documents. Kerr-McGee prepared the RI and FS reports, and U.S. EPA prepared the human health and ecological risk assessment reports.  These documents were finalized in May 2004 and U.S. EPA issued a proposed plan for site cleanup on May 24, 2004.  U.S. EPA held a public meeting on June 2, 2004 to present the cleanup plan and to discuss the community's concerns regarding the approach.  U.S. EPA signed the Record of Decision (ROD) on March 24, 2005 selecting excavation and off-site disposal as the cleanup method for targeted sediments and soils at the site.

Kerr-McGee entered into two separate consent decrees (one with the federal government and one with the local communities).  Given the overlapping issues, both decrees had to be finalized around the same time.  The federal consent decree was finalized on March 30, 2005 requiring Kerr-McGee to design and carry out the cleanup at the site, with the cleanup estimated to cost $71.9 million.  The design and cleanup is being conducted under a phased approach, proceeding sequentially from upstream to downstream, with the site divided into several different sections or "reaches" as described below:

        Reach 1:  creek from storm sewer outfall to May Street

        Reach 2:  creek from May Street to Joy Road

        Reach 3:  creek from Joy Road to Route 59

        Reach 4:  creek from Route 59 to the confluence with the River

        Reach 5C:  river from confluence to Mack Road

        Reach 5D:  river from Mack Road to River Oaks subdivision

        Reach 5E:  river from River Oaks subdivision to Williams Road

        Reach 6:  river from Williams Road to Butterfield Road

        Reach 7:  river from Butterfield Road to Warrenville Dam

        Reach 8:  river from Warrenville Dam to McDowell Dam

Cleanup work at the site began in the summer of 2005 and was completed by the end of 2012.  In January 2009, Tronox (formerly Kerr-McGee) filed for Chapter 11 bankruptcy and ceased work on the site.  U.S. EPA negotiated a settlement of environmental claims with Tronox resulting in a February 14, 2011 a bankruptcy settlement agreement and provided for the creation of the West Chicago Environmental Response Trust, with Weston serving as Trustee. The West Chicago Trust is responsible for fulfilling remaining environmental obligations of the KC/WBDR site and is primarily funded by legally required DOE reimbursements at the rate of 55.2% of site cleanup costs pursuant to the Energy Policy Act of 1992. 

The cleanup work at the Kress Creek site was conducted by Kerr-McGee, Tronox and the West Chicago Environmental Response Trust, along with their contractors, under the oversight of U.S. EPA, the State of Illinois, and the local communities.

Restoration activities had ceased in 2013 due to the lack of DOE funding to provide reimbursements of site cleanup costs.  The West Chicago Trust received partial reimbursements of past cleanup costs in April 2015 and is now preparing plans to complete restoration activities.  Maintenance and monitoring of site restoration will continue for at least three more years, and then the Kress Creek site will be eligible for deletion from the NPL.

Community Involvement

The local community has been very involved in site issues for more than a decade. The Thorium Action Group (TAG) is a very active and vocal community group that has fought hard for the removal of the thorium materials from the West Chicago and DuPage County area.  EPA participated in regular meetings of the West Chicago Intergovernmental Forum, which includes representatives of state and federal regulatory agencies, local community representatives, members of TAG, the PRP, and other interested stakeholders.

In addition, the local community entities (including West Chicago, Warrenville, DuPage County, the DuPage County Forest Preserve District and the West Chicago Park District) entered into a separate consent decree with Kerr-McGee and conducts oversight of site cleanup activities.

The West Chicago Intergovernmental Forum met every month to provide updates to the local communities and regulatory authorities on the progress of the cleanup work.  As worked progressed, the frequency of these meetings were reduced and are now held only on an "as needed" basis.  Minutes of these meetings as well as other site documents can be found at http://www.epa.gov/region5/cleanup/kerrmcgee/index.htm

Many letters have been sent to the EPA Administrator in support of funding for this project, including letters from the US Senate, House of Representatives, Illinois House of Representatives, City of West Chicago, City of Warrenville, DuPage County, and the DuPage County Forest Preserve District.

Congressional Interest

Many letters have been sent to the EPA Administrator in support of funding for this project, including letters from the US Senate, House of Representatives, Illinois House of Representatives, City of West Chicago, City of Warrenville, DuPage County, and the DuPage County Forest Preserve District.

Property Reuse

Land use along the creek and river is primarily a mixture of residential and forest preserve properties.  Future land use is expected to remain the same.


Remedial Project Manager, U.S. EPA
david seely (seely.david@epa.gov)
(312) 886-7058

Community Involvement Coordinator, U.S. EPA
janet pope
(312) 353-0628




Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.


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