Dames & Moore, 1999 - USDA Forest Service

The most visible large game animals are mule. deer, black-tailed deer, and black bear (Dames & Moore
1996). Smaller species of interest, that have not been observed. could include beaver. marten. wolverine.
cougar, lynx, and various rodents. Deer mice and shrews are probably present. Mule deer tracks and scat
are common on the tailings piles, especially where the cover is better established. Golden-mantled ground
squirrels and chipmunks were also common in these areas, and a mannot was observed on one occasion.
Mink are likely to be present in the area, although they have not been observed, probably because of their
nocturnal behavior.
The birds common to the area included bald eagles, hawks,(owls, grouse, and woodpeckers. Violet-green
swallows and barn swallows forage for insects over the tailiilgs piles, and a flock of American pipits was
observed foraging on the tailings piles. Immature red-tailed hawks were observed hunting over the tailings
piles and may nest in the area
1500-Level Main Portal Drainage and see^ Areas
Bats have been observed foraging for insects and touching the surface of the stream that flows from the
main mine portal. On one occasion, Mule deer were also observed drinking from the 1500-level main portal
drainage.
Rare. Threatened. and Endangered Swcies
Dames & Moore (1996) indicated that only two plants with state sensitive status had been identified in the
valley by the Washington Natural Heritage Program (Brewer's cliff-brake and Stellets rock-brake). The
report also noted that the U.S. Fish and Wildlife Service Endangered Species Team had determined that to
the best of their knowledge there are no listed or proposed threatened or endangered animal species in the
Railroad Creek area. However, wolverines were noted as a state sensjtive species by the USFS. Table
7.2.2-2 is a listing of the threatened andlor endangered species known to inhabit the Railroad Creek drainage
area.
7.2.23 Potential Complete Exposure Pathways
The analysis of exposure pathways is critical to an ERA because, by definition, there can be no risk without
exposure. The lack of complete exposure pathways may be due to the absence of a bioavailable form of the
compound of concern, the absence of a transport pathway, or the absence of a receptor. The analysis of
exposure pathways consists of three major elements:
Source of constituent of PCOC and release mechanism
Transport media (or medium) and mechanism of transfer from one medium to another
Point (or area) of potential receptor contact with PCOC
The primary sources of PCOCs considered in this assessment are those associated with the existing source
areas associated with mining advities at the Holden Mine, including the underground mine, waste rock
piles, the mill area, lagoon, and the tailings piles. Potential release mechanisms From these source areas
include surface water runoff, leaching of groundwater from seeps, subsurface interaction with groundwater,
and air transport of particulates From these source areas that contain PCOCs. Through these release
DAMES & MOORE