Ecological Assessments
Contaminants in fish and wildlife that inhabit the Columbia River and the Hanford Site are
routinely monitored. Wildlife may access areas of the site that contain radioactive or chemical
contamination, and aquatic organisms can be exposed to contamination entering the Columbia River
from groundwater discharges along the shoreline. Fish and some wildlife species exposed to
Hanford contaminants have the potential to be harvested for food and contribute to offsite public
exposure. In addition, detection of contaminants or changes in contaminant levels in biota
over time may indicate that animals are entering contaminated areas (for example, burrowing in
waste burial grounds) or materials are moving out of known contaminated areas (for example,
through water, blowing dust, or food-chain transport).
Ecological assessments determine the impact of Hanford's past and present operations on the area
ecology. These assessments also determine the impact of any specific cleanup, operational, or
closure actions. Assessments include determining the concentration of contaminants in ecological
species, the relative health of indicator species, and other activities required to protect
threatened or endangered species.
The data collected to date suggest that maximally exposed individuals of the public are not at
risk from consuming game animals. The results also indicate that wildlife populations monitored
on the Hanford Site are thriving compared to other reference populations.
A single, integrated biological characterization and impact assessment capability brings better
understanding to the potential biological impact associated with the presence of contaminants
in the environment. This approach is a cost-effective means to identify those areas and organisms
that best represent the most likely receptors of Hanford-derived contamination and areas where
both short- and long-term contaminant surveillance and biological impact monitoring should be
conducted. Integration of these activities will:
document the biological resources present, identify biota pathways that contain elevated levels of Hanford-derived contamination, examine measurable biological endpoints that indicate the relative condition of the receptor organisms, and provide the site-specific data necessary to examine, calibrate, or validate contaminant transport and ecological risk assessment models proposed as screening tools for the Hanford Site close-out plans.
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