ATSDR and IDPH conclude, based on data reviewed, that the Mason City Coal Gas Site poses
no apparent public health hazard. No completed exposure pathways to site contaminants leading
to adverse health effects have been identified. Potential exposure pathways, however, exist under
current site conditions.
The shallow aquifer on-site and off-site is contaminated with PAHs, benzene, and lead at levels
that could cause health problems if people were to come into contact with the contaminants. If
contaminants migrate to off-site domestic wells, or if the contaminated groundwater is used for
domestic consumption, exposure to site-related contaminants is possible.
The waste pile contains contaminated materials excavated from previous source areas on-site.
During remedial activities, exposure can be avoided if workers adhere to current occupational
safety standards.
Site access is restricted by a chain-link fence; however, no signs were posted to warn people of
hazardous wastes in the area.
ATSDR's Health Activities Recommendation Panel (HARP) determined that potential exposure
could be avoided if local health agencies provide appropriate information to clean-up workers and
the community.
RECOMMENDATIONS AND ACTIONS
The purpose of the Recommendations and Actions section is to provide recommendations and
actions needed to protect the public health as activities proceed at the site. Although no
completed exposures have been identified at the site, conditions exist that could result in exposure
to site contaminants. The recommendations and actions listed, if implemented, will prevent
exposure at levels that could cause people to become sick.
Actions Completed:
Provide on-site remedial workers with adequate training and protective equipment in accordance with 29CFR1910.120 and follow appropriate guidelines and standards prescribed by the Occupational Safety and Health Administration, the National Institute for Occupational Safety and Health, and the American Conference of Governmental Industrial Hygienists. EPA requires and approves a site-specific Health and Safety Plan that must be followed before workers begin activities. That plan incorporates worker safety requirements.
Actions Planned:
Institutional controls should be considered to prevent the installation of new water supply wells for domestic purposes within the contaminated portion of the aquifer. If wells are developed in those areas, a monitoring program should be implemented. IDPH will notify the appropriate authority about well installations and will make EPA aware of the necessity of well monitoring should wells be developed in the area of contamination.
Protect people on and off the site during remediation from exposure to airborne particulates or vapors that may be released. The local health department will notify workers and community members of their potential for exposure during the clean-up activities at the site and advise them on ways to avoid or minimize exposure.
Warning signs should be posted to prevent trespassing at the site and the integrity of the fence structure should be maintained. IDPH will share this information with EPA for consideration.
No further actions are planned at this time. If new data become available that indicate a need for further follow-up health actions, IDPH will inform the community and other agencies.
PREPARERS OF THE REPORT
IDPH Public Health Assessment Team
Russell Currier, DVM, MPH
Environmental Epidemiologist
Division of Health Protection
Iowa Department of Public Health
Brad V. Cudal, M.D.
Environmental Specialist
Division of Health Protection
Iowa Department of Public Health
Arlene Jacob
Environmental Specialist
Division of Health Protection
Iowa Department of Public Health
Richard L. Welke, B.A.
Environmental Specialist
Division of Health Protection
Iowa Department of Public Health
Elena Babak, Ph.D.
Environmental Specialist
Division of Health Protection
Iowa Department of Public Health
ATSDR REGIONAL REPRESENTATIVE
Denise Jordan-Izaguirre.
Senior Regional Representative
EPA Region VII
ATSDR Technical Project Officer
Gail D. Godfrey
Environmental Health Scientist
Division of Health Assessment and Consultation
CERTIFICATION
The Mason City Coal Gas Site Public Health Assessment was prepared by the Iowa Department of Public Health under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the public health assessment was begun.
Gail D. Godfrey
Technical Project Officer
Superfund Site Assessment Branch
Division of Health Assessment and Consultation (DHAC)
ATSDR
The Division of Health Assessment and Consultation, ATSDR, has reviewed this health
consultation, and concurs with its findings.
Robert C. Williams, P.E., DEE
Director,
Division of Health Assessment and Consultation
ATSDR
