Occidental Chemical Site, Whitehall, Michigan

Investigation Results

• The groundwater underlying the OCC facility is contaminated with volatile organic compounds (VOCs) and C-series compounds.

• The groundwater contaminant plume is 2000 feet wide and 6500 feet long, migrating from north to south. The plume is intercepted by the purge well system before it can discharge to White Lake. The contaminated groundwater poses a significant risk to human health if used as a water source.

• Waste trapped in subsurface soil continues to contaminate groundwater, Groundwater contamination poses a potential risk to human health for hundreds of years if the waste is not removed.

• Surface soil is locally contaminated with VOCs, C-series compounds, mirex, and dioxin. Institutional controls are necessary to restrict areas to industrial use since soil contamination poses an unacceptable risk under residential use.

• Soil remediation is necessary in the Former Small Disposal Pile Exposure Area to protect human health and the environment.

• A soil cover is necessary in the Former Burn Pit Exposure Area to minimize risk to human health and the environment.

• Subsurface soil is contaminated in the Northern and Central Exposure Areas, including "No Mans Land". The extent of waste remaining in soil will be investigated and feasible corrective measures taken.

• Approximately 3000 cubic yards of White Lake sediment is contaminated with C-series compounds, PCBs, and asbestos from past outfall discharges. The sediment poses a risk to human health via fish consumption.

• VOCs discharging to the surface from contaminated subsurface soil and groundwater do not pose a risk to human health if buildings were constructed on-site.

Scope of Corrective Action

The environmental problems at the OCC facility have been partially addressed through the Consent Judgement and interim actions under the RCRA Order. The actions have helped stabilize the release of contaminants to water, soil, and air. Final actions are still necessary to fully address the remaining contaminants in the groundwater, soil, and sediment.

Contaminated groundwater is a principal threat to human health because of long-term potential for direct ingestion through drinking water wells and discharge to White Lake. Cleanup objectives are to contain the migration of contaminated groundwater and to reduce contaminant concentrations below Michigan Part 201 cleanup goals in a timely manner.

Local areas of contaminated soil are a risk due to the long-term potential for direct human contact and migration of contaminants to groundwater. The cleanup objectives are to reduce the contaminant concentrations below Michigan Part 201 cleanup goals, reduce migration to groundwater in a timely manner, and isolate contaminated soil from contact.

Contaminated sediment in White Lake poses a risk to the aquatic environment and people consuming fish from the lake. Cleanup objectives are to minimize exposure to the sediment by eliminating the exposure pathway. Calculations show that eliminating exposure to concentrations of PCBs and hexachlorobenzene at levels above 2 ppm and 0.45 ppm respectively, would significantly reduce risk to human health and the environment.

Click here for the Summary of Corrective Measures.

Click here for the Proposed Remedy by U.S. EPA.

Contact Information

Kirk Riley, rileyki@egr.msu.edu
Dr. Mike Dybas, dybas@egr.msu.edu
Atiq Syed, syedatiq@egr.msu.edu