ATSDR -- FY 1999 AGENCY PROFILE AND ANNUAL REPORT
In 1952 the plant started operations to enrich uranium 235 by a gaseous
diffusion process. Early processes included limited production of uranium
hexafluoride and uranium metal. Over time, TCE and Tc-99 contaminated local
groundwater. ATSDR's investigations also found other conventional and
radiologic contaminants in air, surface soils, sediments, and surface waters.
These originated from different sources at the site.
ATSDR obtained approximately 700,000 data values, geo-locators for each
sample station, and other data from the plant's environmental database. By
incorporating these data into a GIS system, ATSDR was able to visualize
patterns of contaminant concentrations in the different media and to integrate
this information with demographic information for the vicinity. GIS provided
both a visual image of areas affected and a numerical value representing the
persons potentially affected by the contaminants in each media. It also
generated a demographic breakdown of different types of populations. When
sample locations were depicted graphically, areas that had not been sampled
were easily identified. ATSDR also determined past plume migration and
estimated exposure durations.
ATSDR evaluated potential exposure doses to airborne radionuclides
using EPA's Clean Air Act Assessment Package and demographic and off-site
distance information provided by GIS. ATSDR also performed an air
the analysis onto maps to determine potentially exposed populations.
ATSDR released a public health assessment that generally concluded that
the offsite community was not exposed to contaminants at levels of public
health concern during normal plant operation. It did find that in five residential
wells, past exposures to maximum concentrations of TCE or lead posed a
health hazard for two or three young children. Additionally, it determined that
if new wells are drilled into the contaminated groundwater plume or old wells
are used, exposures to maximum concentrations in the groundwater plumes
would pose a future health hazard for children and adults.
Kelly Air Force Base
San Antonio, Texas
Members of the community neighboring Kelly Air Force Base, Texas,
expressed concerns about fuel vapor odors and other odors coming from the
base. They asked if there was a relationship between these odors and the
occurrence of health effects, such as nausea, headaches, difficulty in breathing,
and cancer. To determine if any emissions from the base could be linked to
those symptoms, ATSDR gathered and researched several types of information,
including historical information about the base, environmental information,
health outcome data, and information provided by the community.
After reviewing information about the chemicals being emitted and their
sources, ATSDR used an air dispersion model to estimate the dispersion of
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