HEALTH CONSULTATION
UNION MECHLING COMPANY
SENECA, GRUNDY COUNTY, ILLINOIS
Because data are limited, IDPH concludes that the site, in its present condition, presents an indeterminate health
hazard to trespassers who contact contaminated on-site soil. Off-site well water samples did not contain site-related
contaminants; however, on-site groundwater has not been adequately characterized and migration of site contaminants
to drinking water supplies is a potential concern. Off-site private well water may contain thallium that can be harmful
if consumed over long periods of time. IDPH has not been provided any private well data other than that collected in
1991. Therefore, no conclusion can be drawn about the current status of the private wells in the area.
IDPH makes the following recommendations:
- Prevent public access to the site.
- Install groundwater monitoring wells to better characterize groundwater at the site and what may be migrating from the site.
- Continue testing private wells near the site and provide the data to IDPH for public health implications if constituents or levels have changed.
- Although contaminants present in private well water are not known at this time to be site related, owners of the private wells containing elevated thallium concentrations are advised to continue to use an alternative drinking and cooking water source because the water may not be safe to drink over a long period of time.
Cary Ware
Illinois Department of Public Health
This Union Mechling Health Consultation was prepared by the Illinois Department of Health under Cooperative Agreement with the Agency for Toxic Substances and Disease Registry. It is in accordance with approved methodology and procedures existing at the time the Health Consultation was initiated.
Gail D. Godfrey
Technical Project Officer
SPS, SSAB, DHAC
The Division of Health Assessment and Consultation (DHAC), ATSDR, has reviewed this Health Consultation and concurs with its findings.
Richard Gillig
Chief, SPS, SSAB, DHAC, ATSDR
- Union Mechling CERCLA Screening Site Inspection Report. IEPA, Springfield, Illinois, 1991.
- Union Mechling CERCLA Site Inspection Prioritization Report. IEPA, Springfield, Illinois, 1994.
- Memorandum: Phase I Site Investigation Report at Union Mechling, Seneca, Illinois. From Steve Anderson, On-Scene Representative, Harza Environmental Services, Inc. to Hank Konzelmann, IEPA Project Manager. June 22, 1989.
- Greg Dunn, April 29, 1997. Telephone communication with Greg Dunn, IEPA, Springfield, Illinois, regarding sealing of on-site wells.
- Site Assessment Report For National Marine/Union Mechling Site, Seneca, Grundy County, Illinois. Ecology and Environment, Incorporated, Chicago, Illinois. June, 1996.
- Letter: Union Mechling Site/Olson's Auto Wrecking. From Kevin Turner, On-Scene Coordinator, USEPA, to Robert O'Neil and John Barnes, Union Marine, Inc. (Vectura Group). March 25, 1997.
- Memorandum: Request for a Time-Critical Removal Action at the Union Mechling Site, Grundy County, Seneca, Illinois. From Matthew Williams, On-scene Coordinator, USEPA to William Muno, USEPA.
- ATSDR. February 1996. Draft Update Toxicological Profile for PCBs. Atlanta, GA: US Dept. of Public Health and Human Services, Agency for Toxic Substances and Disease Registry.
- ATSDR. April 1993. Update Toxicological Profile for Lead. Atlanta, GA: US Dept. of Public Health and Human Services, Agency for Toxic Substances and Disease Registry.
- ATSDR. May 1994. Update Toxicological Profile for 4,4'-DDT, 4,4'-DDE, 4,4'-DDD. Atlanta, GA: US Dept. of Public Health and Human Services, Agency for Toxic Substances and Disease Registry.
- ATSDR. September 1992. Toxicological Profile for Antimony. Atlanta, GA: US Dept. of Public Health and Human Services, Agency for Toxic Substances and Disease Registry.
- ATSDR. July 1992. Toxicological Profile for Thallium. Atlanta, GA: US Dept. of Public Health and Human Services, Agency for Toxic Substances and Disease Registry.


