Clark Environmental Consulting, LLC
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Assessing risks to human health requires knowledgeable approaches.


Health Risk Assessment

Human health risk assessments form a primary component in the evaluation of risks posed by environmental contamination.  During their careers, Dr. Milton Clark and scientists with CEC have developed over 100 health risk assessments for hazardous waste sites, situations involving human exposure to pesticides, contaminated soils and sediments, and toxic chemicals in foods.  We work with clients to ensure that work products meet federal and state risk assessment requirements and regulatory criteria.  Currently, CEC does not undertake projects where the United States government is a party or has a direct and substantial interest.

Health Risk Assessment Projects:

Contaminated Sediments: Waukegan Harbor, Illinois

At this Superfund site over one million pounds of polychlorinated biphenyls (PCBs) were discharged into Waukegan Harbor and Lake Michigan. PCB levels in sediments were over 10,000 parts per million and fish were found to have some of the highest PCB levels ever observed.  While working for U.S. EPA, Dr. Milton Clark performed a multi-media risk assessment to assess current human health risks as well as risks during and following remedial actions.  This risk assessment and risk management analysis led to an effective harbor cleanup at reasonable costs.  Following cleanup, PCB levels in fish were dramatically lowered reducing public health risks.

Contaminated Soils: Bloomington, Indiana

Industrial manufacture and disposal of PCB transformer oils in several area landfills resulted in contamination of soils, groundwater, and surface waters.  For this complex Superfund site, human health risk assessments were developed to establish appropriate cleanup levels. To address public health concerns, risk communication presentations were made to the public prior to and during cleanup operations. Remedial actions were undertaken in a cost-effective manner to remove the highest PCB contaminated materials, cap remaining soils in landfills, and install water treatment.

Contaminated Fish and Health Risks

Dr. Milton Clark has pioneered risk assessment techniques for consumption of contaminated fish from Superfund and RCRA sites in the Great Lakes including Manistique Harbor, Michigan; Fox River, Wisconsin; the Kalamazoo River, Michigan; and Tittabawassee River, Michigan.  These risk assessments have supported Superfund based remedial investigations (RI), feasibility studies (FS) as well as EPA record of decisions (ROD).  Defensible risk assessments for fish consumption require careful balancing of chemical exposures and fish ingestion rates.  It is important not to overstate chemical exposure risks, but a the same time ensure that sensitive populations, such as certain ethic groups, women of child bearing age and children, and the developing fetus are protected.