Dames & Moore, 1999 - USDA Forest Service

evaluated by screening constituent concentrations against drinking water criteria. No constituents detected
in the Lucerne well exceeded screening criteria and therefore this route of exposure was eliminated from
further evaluation.
7.1.5.8 Fib Muscle Tissue
PNL and Ecology fish muscle tissue daui were screened against U.S. €PA Region 111 Risk-Based
Concentrations for ingestion of fish. None of the muscle concentrations exceeded the screening criteria and
therefore no risk to human health exists due to ingestion of the detected metals in edible fish tissue.
7.1.5.9 Summary of Conclusions
Figure 7.1-3 illustrates the combined results of the screening level human health assessment and the site-
specific human health risk assessment. Figure 7.1-3 shows that the environmental conditions at the Site and
Holden Village do not pose an unacceptable risk to potentially exposed populations, i.e., residents and
recreational users of the Site, and USFS personnel. Table 7.1-42 summarizes the risks associated with ,each
exposure area and IHS at the site. An evaluation of the cumulative risks for each potentially exposed
population also demonstrates that cumulative cancer and noncancer risks are acceptable (see Section
Cumulative Risk 4.3).
All conclusions are based upon very conservative screening criteria and site-specific assumptions which, for
all practical purposes, overestimate the risk posed by the Site.
7.2 ECOLOGICAL RISK ASSESSMENT
7.2.1 Methodology
The intent of this risk assessment is to:
a Address protection of the environment under the State of Washington Model Toxics
Control Act, Chapter 173-340 Washington Administrative Code (WAC), CERCLA, and
the National Contingency Plan (NCP) through assessment of ecological risk
a Provide a risk assessment and risk management framework that will support decision
making andlor identification of further data gaps (if any) for the RVFS and remedy
selection
a Support an injury determination to focus further studies that may evaluate any loss of
resources or services under NRDA rules
The objectives were developed using the most recent concepts and available guidance on ecological risk
assessment (USEPA 1994; 1998). In keeping with current guidance and the NCP, the specific objectives of
the study were to:
• Characterize the nature and extent of previous human activity-related conditions at the
Site
Provide a limited characterization of the ecological populations, communities, and
ecosystem at the Site
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FINAL RI REPORT