Dames & Moore, 1999 - USDA Forest Service

7.1.5.4 Surface Water and Fish
Surface water sample results were divided into three areas based on physical location, as follows:
1) Railroad Creek adjacent to the Site, 2) Railroad Creek downgradient of the Site, and 3) Copper Creek.
Screening of constituent concentrations resulted in the elimination of Railroad Creek as an area of concern.
Only one constituent (molybdenum) exceeded screening criteria in Copper Creek and was selected as an
IHS for surface water and fish. Risks for Copper Creek surface water were evaluated for both incidental
ingestion of surface water during recreational activities, and ingestion of fish by sport fishermen. Hazard
quotients for molybdenum were 6.44 x 1w2 for ingestion of water and 3.18 x 10" for ingestion of fish. both
of which are below the allowable MTCA hazard quotient. There were no cancer risks calculated for this
media since the IHS was not a carcinogen.
The findings of no significant risk for ingestion of fish is supported by the data collected in 1989/1991
and 1992 by PNL and Ecology. PNL and Ecology collected fish muscle tissue from three locations in
Railroad Creek, including at Lucerne, and from 25-Mile Creek (a reference site south of Lucerne). PNL
concluded there were no significant overall locational differences in metal concentrations for muscle
tissue, and that results indicated little risk to human health through consumption of trout. Screening of
this muscle tissue data against U.S. EPA risk-based concentrations confined that residual metals in
edible tissues are well below levels of concern, both at the site and downgradient of the site. (287)
7.1.5.5 Seeps, 1500-Level Main Portal Drainage, and 1500-Level Ventilator Portal Seepage
Seep, 1500-level main portal drainage and 1500-level ventilator portal seepage data were evaluated
separately. No constituents were selected as IHSs for ventilator portal drainage. Constituents exceeding
screening criteria in seeps and mine portal drainage were selected as IHSs and evaluated in the site-specific
risk assessment. Noncancer hazard quotients for all IHSs in both media were below the allowable MTCA
hazard quotient. There were no cancer risks calculated for these media since IHSs were not carcinogens.
The hazard quotients ranged from 1.15 x 1 c2 for manganese in the 1500-level main drainage to 5.2 1 x 10"
for cadmium in the 1500-level main portal drainage.
Lead w& present in both seeps and the 1500-level main portal drainage at concentrations exceeding the
MTCA Method A level; however, because no toxicity criteria exist. for this constituent, site-specific risks
could not be evaluated. While exposure concentrations exceed MTCA Method A level, the exposure
frequencies and water ingestion rates expected at the site are significantly less than those upon which the
cleanup criteria is based. Therefore, concentrations of lead in seeps and 1500-level main portal drainage are
not expected to cause effects in potentially exposed populations.
7.1.5.6 Sauna Dipping Pool (Copper Creek Diversion)
Risks associated with the sauna dipping pool were evaluated by screening water from the Copper Creek
diversion against drinking water criteria. No constituents detected in the Copper Creek diversion exceeded
screening criteria and therefore this route of exposure was eliminated from further evaluation.
7.1.5.7 Groundwater
. Groundwater at the site is not considered useable for drinking water purposes and therefore was not
screened for exceedances of drinking water criteria. Groundwater collected at the Lucerne USFS well was
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17693005019Uuly 27. 1999.5:16 PMDRAFT FINAL RI REPORT