Dames & Moore, 1999 - USDA Forest Service

I
There are no promulgated federal or State of Washington regulations regarding freshwater sediment
chemical criteria or criteria related to other accumulated solid materials. In 1997, Ecology published a
guidance document, "Creation and Analysis of Freshwater Sediment Quality Values in Washington State,"
which provides guidance information on possible sediment threshold levels and suggests "possible"
proposed guidelines (Ecology, 1997). The Ecology Freshwater Sediment Quality Values (FSQVs) are
provided in Table 5.1-1. The only current regulatory citation for freshwater sediments is specified in WAC
173-204 Section 340 for freshwater sediment quality standards and states "the department shall determine
on a case-by-case basis the criteria, methods, and procedures necessary to meet the intent of this chapter."
Currently, proposed changes are under review regarding this regulation but have not been promulgated.
Guidelines for freshwater sediments have been developed by Long & Morgan (1990, 1995) and the
Canadian Council of Ministers of the Environment (CCMI, 1991) and are considered TBCs that may also be
used for comparison; however, these guidelines are not further discussed in this section. It is understood
that these guidance have limitations ind uncertainties associated with them. The FSQVs available for
comparison to historical and RI sediment data are considered to be preliminary as the "possible" guidance
levels do not reflect Site-specific conditions.
5.2 SOIL
Surface soil samples were collected during the RI from locations throughout the Railroad Creek drainage
and in Holden Village, the baseball field near Winston home sites, the maintenance yard, the lagoon area,
the surfaces of the three tailings piles, and downwind of the Site area for windblown tailings. Subsurface
soil samples were collected from the maintenance yard, the lagoon area, and the tailings piles.
Samples were analyzed for metals (aluminum, arsenic, barium, beryllium, cadmium, calcium, chromium,
copper, iron, lead, magnesium, manganese, molybdenum, nickel, potassium, silver, sodium, thallium,
uranium, and zinc). Samples collected in the maintenance yard and the lagoon area were also analyzed for
total petroleum hydrocarbons and PCBs. The samples were submitted for analyses to Analytical Resources
Incorporated (AM) in Seattle, Washington.
The following sections discuss the data collected during the RI for each of the geographic locations, as well
as historical data reported by the USBM and USGS. The historical data are assumed to be of adequate
quality to include in the RI for comparative purposes and for evaluating PCOCs except where noted.
Sampling procedures and analytical methodology used hi&orically may differ from procedures and methods
used during the RI. These differences may result in data that are inappropriate or not beneficial to use for
Site assessment due to increased detection limits, different sample locations, and different analytical
parameters. Where appropriate, historical data are discussed with the RI data. RI and historical sample
locations are shown on Figures 5.2-1 through 5.2-5. Analytical data are summarized in Tables 5.2-1
through 5.2-5. A summary of the PCOCs identified in the soil matrix at the Site is provided in Table 5.2-6.
5.2.1 Background
Area background was statistically calculated from analytical data collected for this purpose. The Site
sample data were compared initially to the area background values.
5-5
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