Dames & Moore, 1999 - USDA Forest Service

8.3.5.2 Lucerne Bar & Stehekin River Bar
Sediment was collected from near the mouth of Railroad Creek at Lucerne Bar and a reference site near
the mouth of the Stehekin River, approximately 10 miles north of Lucerne Bar in Lake Chelan. The
results indicate concentrations of zinc slightly above FSQVs (approximately 5 percent higher)for one
sample out of 12 collected at Lucerne Bar; the sample was collected near the eastern margin of the study
area. All others metal concentrations were below FSQVs.
8.3.6 Other Media
8.3.6.1 Ferricrete
Three samples of femcrete were collected during the RI to characterize the chemistry to assess the
formation of the deposits. The samples were collected from the areas near seeps located northwest and
northeast of tailings pile. Iron was the dominant metal present, followed by lessor concentrations of
aluminum, magnesium, calcium, and copper.
8.3.6.2 Flocculent
Three samples of flocculent were collected during the RI from the substrate in Railroad Creek to assess the
formation of the precipitates. The flocculent was similar in metals composition to femcrete, but generally
contained a higher proportion of iron (up to 43 percent higher).
8.3.6.3 Portal Film
Two samples of film or flocculent were collected from the portal drainage substrate. One sample was
collected each during the July and SeptemberIOctober 1997 events. Aluminum was the dominant metal in
the portal film, followed by iron, calcium, copper, and zinc. Aluminum was approximately twice as high in
July when compared to September/October. Zinc and copper were higher by approximately two times in
September/October as compared to July.
8.3.6.4 Air
Air samples were collected as part of the pre- and post-construction monitoring associated with the tailings
pile rehabilitation project completed at the Site by the USFS between 1989 and 1991. A dust bucket study
was completed between 1974 and 1976; however, the dust was not chemically characterized. The post-
construction sampling consisted of establishing air monitoring stations both west and east of the Site, as well
as on top of the tailings piles. The results indicate that the metals of highest concentrations were aluminum,
calcium, magnesium, potassium, and sodium. These data were utilized to evaluate potential risk as
discussed in a later subsection.
8.4 CONTAMINANT PATHWAYS AND CHEMICAL LOADING
8.4.1 General
The contaminant pathways were evaluated based on the potential sources of contaminants and chemistry as
discussed in the previous subsection. This discussion presents the contaminant pathways for the western
and eastern portions of the Site, and Railroad Creek. The western portion of the Site principally includes the
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