Hazardous Waste Sites

Hazardous waste sites come in all sizes, shapes and levels of complexity. Some sites consist of a few abandoned drums left in an unobtrusive location, while other sites cover many acres and are located in a populated area. A site may be contaminated by one chemical, or there may be a complex mixture of chemicals affecting a region.

Stacked drums and overturned containers leaking hazardous chemicals. The Missouri Department of Health and Senior Services (DHSS) assesses the risks to public health and provides health information to agencies and to the public regarding these sites. DHSS works cooperatively with the Agency for Toxic Substances and Disease Registry (ATSDR), the United States Environmental Protection Agency (EPA) and the Missouri Department of Natural Resources (MDNR), in the evaluation, oversight and management of hazardous waste sites.

DHSS's responsibilities at various hazardous waste sites include conducting:

Public Health Assessments and Technical Reviews of Human Health Risk Assessments for Superfund Sites

DHSS is involved at several stages in the evaluation, cleanup and long-term management of Superfund sites. During the early stages of investigation of a site, EPA, MDNR or members of the public may ask DHSS for input on a variety of site-related health issues. Verbal or written responses may be provided to the public, the agencies or both.

The Comprehensive Environmental Responsibility, Compensation and Liability Act (CERCLA, or Superfund) is a federal program designed to clean up the nation's abandoned or uncontrolled hazardous waste sites. Superfund clean-up activities focus on those sites that cannot be cleaned up under other government programs. Most Superfund sites are either heavily contaminated, fairly complex or both. The Superfund program though CERCLA, is action oriented and is intended to augment other federal or state authorities. This "Super" fund is generated through a broad-based corporate tax, chemical feedstock tax, petroleum tax, and additional general revenues.

If the contamination and potential for exposure to the contamination are significant enough, a site may be listed on the National Priorities List (NPL). The NPL, established and maintained by the EPA, is a list of the most serious uncontrolled or abandoned hazardous waste sites in the nation. Within one year of proposal for listing on the NPL, DHSS must complete a Public Health Assessmentfor the site. A public health assessment reviews information about hazardous substances at a site and evaluates whether exposure to those substances has occurred and if that exposure might cause any harm to people. These assessments are conducted cooperatively with the ATSDR, a federal health agency.

In addition to public health assessments, DHSS may be asked to comment on specific issues at any phase during the evaluation and cleanup of a hazardous waste site by the public or the regulatory agencies. Responses to these specific inquires may be given in a health consultation, in a comment letter, as a technical assist, or verbally.

DHSS provides technical reviews of risk assessments and other site related documents prepared by other entities as part of a Remedial Investigation and Feasibility Study (RI/FS). The RI/FS is the process established by the Superfund program for characterizing the nature and extent of contamination at a site, characterizing potential site risks, and for developing and evaluating remedial options. A human-health risk assessment evaluates potential, current or future exposures at a site. In addition, it provides a quantitative estimate of the likelihood of health effects occurring if no actions were taken to clean up the site. The results of the risk assessment provide the basis for remedial decisions made about the site. During the analysis of remedial alternatives, site-specific preliminary remediation goals (PRGs) are formed, which are clean-up goals developed to be protective of human health and the environment.

Once a site is cleaned up, the regulatory agencies are required to conduct periodic site reviews. DHSS participates as requested in these reviews to ensure that the remedies used at the site remain health-protective.

For more information on the Superfund process, visit the websites for EPA, Region 7 EPA and MDNR.

Health Assessments for the Registry

The Registry of Confirmed Abandoned or Uncontrolled Hazardous Waste Disposal Sites in Missouri (the Registry), published by the MDNR, is a list of sites that contain hazardous waste. The Registry provides public information about certain hazardous waste sites and helps to ensure that potential owners, occupants and purchasers of these sites are informed about hazards and legal obligations associated with the sites. Additionally, the Registry provides for a variety of institutional controls that allow residual contamination to remain at a site while ensuring the protection of human health and the environment.

DHSS is a member of the Site Assessment Committee, the group that annually evaluates and ranks sites listed on the Registry. DHSS is responsible for assessing the potential human health effects of exposure to contamination at each Registry site on an annual basis. These health assessments are provided to MDNR and reported in the Registry annual report.

Document Reviews for Brownfields/Voluntary Cleanup Programs

Brownfields are abandoned or underused properties that are, or may be, contaminated by hazardous substances. Expansion, redevelopment, or reuse of these sites may be complicated by the actual or perceived contamination. Cleaning these sites and getting them back into productive use provides environmental benefits, as well as economic benefits for the community. MDNR's Brownfields/Voluntary Cleanup Section provides state oversight for voluntary cleanups. DHSS staff review site-specific sampling plans, risk assessments, proposed plans and other site-related documents and provide input to MDNR and the public on health issues related to these sites.

More information on Brownfields and Voluntary Cleanup programs may be found on the EPA and MDNR websites.

Health Consultations and Other Services

DHSS receives requests for information on a variety of subjects, some related to hazardous waste sites, some related to chemical exposures. These requests may come from the public or from other agencies and may be submitted by phone, in writing, or by email (See contact information on right side of page). Responses may take the form of verbal advice over the phone, letters, technical assists or health consultations. Health studies and exposure investigations may also be conducted to determine potential health effects from exposure to the hazardous substances.

Health Education

To assist the public in preventing exposure to contaminants at sites, DHSS provides a variety of health education and community involvement activities. Some sites have complex exposures that may take years to remediate and involve extensive health education activities whereas other site involve very little. Community involvement and health education have many facets: