EPA Sends letter to 117 West Chicago Homeowners

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 5
77 WEST JACKSON BOULEVARD
CHICAGO, IL 60604-3590

Si gusta obtener una explication de esta carta en el idioma espaiiol, por favor Ilame a Pablo Valentfn al312-353-2886,o al 1- 800-621 -8431 x 32886

Dear Property Owner:

        In recent weeks you may have heard news reports that some residential properties in West Chicago might have buried radioactive thorium concentrations exceeding U.S.  Environmental Protection Agency's (EPA7s) current cleanup standards. The properties in question are those excavated in the 1980s by Kerr-McGee Chemical (Kerr-McGee) under an agreement with the City of West Chicago. Your property was part of that cleanup project. EPA is evaluating earlier radiation data and the extent and depth of cleanup at your property to determine if there is a possibility that buried residual thorium exceeding EPA's current cleanup level may remain at your property. As the evaluation progresses, we will provide you with additional information regarding your property.

        During the 1980s thorium cleanup project, Ken-McGee focused on the identification and removal of potentially unsafe thorium levels in the residential areas of West Chicago. At that time, Kerr-McGee removed thorium contamination from 117 properties in West Chicago. Later, in 1994, EPA ordered Kerr-McGee to clean up residential properties to more recently developed EPA standards. The 1994 EPA-ordered cleanup resulted in the
removal of additional thorium- contaminated soil from 94 of the 117 properties that Kerr-McGee had excavated in the 1980s. The 1994 cleanup also removed thorium contaminated soil from an additional 5 82 properties.

Why has this question come up now?

        Your property is one of the 117 properties that was part of the 1980s cleanup project.  After thorium-contaminated soil was excavated during the 1980s, the excavated soil was replaced with clean backfill soil. Later, in the 1990s and early 2000s, EPA re-examined properties and Kerr-McGee conducted the EPA-ordered cleanup. It is possible that clean backfill soil from the 1980s may have shielded residual thorium contamination that remained at the base of the 1980s excavation. That clean backfill soil may have made it difficult for radiation detection instruments to identify residual contamination above EPAts cleanup standard, if any existed. The City of West Chicago first raised this possibility to EPA and Kerr-McGee several years ago. At that time, EPA was focused on related thorium cleanup projects in the West Chicago area.

        It is possible that some of the 117 properties that underwent cleanup in the 1980s might still have buried thorium deposits exceeding EPA's 1994 standards. However, if any such deposits remain, the thorium levels would be low and not much above EPA7s 1994 standards. Also, because the material is buried, it is not causing any current exposure. - Nearly all of the 117 properties were retested by EPA in the 1990s and 2000s (only 4 of the 117 properties were not retested), and 94 of those properties had additional thorium contaminated soils removed as part of the EPA-ordered cleanup. Those 94 properties, as well as the 19 other properties that were retested but had no additional cleanup, have no radiation levels at the surface exceeding EPA's 1994 standards. Also, because some of the 117 properties were extensively re-excavated in the 1990s and 2000s as part of the EPA-ordered cleanup, EPA knows that certain properties have no buried residual contamination remaining.

What is EPA doing to determine whether or not there may be buried thorium contamination on your property?

        EPA is carefully analyzing the data and excavation information for each property that was part of the 1980s cleanup project, including your property. We expect for certain properties, especially properties that were entirely re-excavated during the EPA-ordered cleanup in the 1990s and 2000s, existing information will show no reason for concern that any buried contamination remains. EPA hopes to complete a preliminary evaluation of these 117 West Chicago properties by this October. Depending on the results of the preliminary evaluation, EPA may decide to sample certain properties to determine whether any additional assessment is warranted. EPA will share the details of its analytical approach with thorium remediation experts representing the City of West Chicago and Tronox(Kerr-McGee Chemical's successor), as well as interested property owners. The results of EPA's individual property analyses will then be shared with the City, Tronox and the respective property owner.

        If you have any questions or concerns regarding this complex situation, please call me at (3 12) 886-4760. Also, if you have concerns about buried residual contamination on your property and are planning any major excavation work, please contact me. You may call anytime. If I am not available when you call, please leave me a message with your name and contact information so I can return your call promptly.

Sincerely,
Rebecca Prey
Remedial Project Manager
Superfund Division
cc: City of West Chicago
Tronox LLC
Sen. Richard Durbin