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Found along the eastern boundary of the Project Area (approximately 9 percent of the total
area) is the Rock outcrop-Vanocker complex, 50 to 75 percent slopes soil unit. This unit is found
at elevations of 3,600 to 6,200 ft. and residuum and alluvium weathered from sedimentary rock.
Sedimentary rock outcrop comprises most of this unit and the profile is generally 0 to 1 inch
slightly decomposed plant material, 1 to 3 inches loam, and 3 to 61 inches very channery clay
loam (NRCS, 2011). This complex is found along the steep eastward-facing slopes in and near
Cole Canyon.
Soil observed at Beaver, Whitetail, and Whitelaw creeks is the Lynx silt loam (0 to 3 percent
slopes). This unit is alluvial in deposition and is derived from the surrounding igneous,
metamorphic, and sedimentary rocks. Silt loam is generally found from 0 to 27 inches and silty
clay loam is found from 27 to 60 inches along these drainage bottoms.
5.9.2 Baseline Soils Survey
RER initiated a baseline soil survey within the Project Area. Soil mapping and sampling was
conducted from June 25 through 28, and July 4, 2012 after all archeological clearances were
completed. Field mapping was conducted according to techniques and procedures outlined in
the National Cooperative Soil Survey. WDEQ-LQD Guideline 1 (Topsoil and Overburden) was
used as a guide during all phases of the study. Mapping was performed to an Order 2 scale on
the majority of the Project Area, with more detailed sampling and mapping being performed
where surface disturbing activities may occur. NRCS mapping, vegetation, and topography will
be utilized for preliminary delineation, in conjunction with field verification of map units and exact
boundaries. Actual soil boundaries were identified in the field by exposing soil profiles to
determine the nature and extent of soil series within the Project Area. Soil mapping utilized 2009
USDA National Agriculture Imagery Program (NAIP) true color ortho aerial imagery for base
map purposes.
Resulting from the baseline soils survey, it can be assumed that an average of 1.25 feet of
topsoil and subsoil will be salvaged from all disturbed areas within the project boundary.
Disturbed areas include the PUG Plant, the Waste Rock Facility (including the Low Grade Ore
Stockpile), the Mineable Pit, haul roads, and light traffic roads. During operations, these soils
will be stockpiled in two locations as shown on Map 4.2-2. The total estimated volume of
salvageable topsoil and subsoil is approximately 1.6 million cubic yards. The total volume of
stockpile #1 is approximately 575,000 cubic yards. The total volume of stockpile #2 is
approximately 1,022,000 cubic yards.
5.9.3 Design Features/Environmental Protection Measures
RER has identified the following design features/environmental protection measures to reduce
potential impacts to soils:
Any long-term surface disturbances will have useable topsoil and subsoil removed
and stockpiled for later reclamation use. Topsoil piles will be clearly marked and
kept separate from spoils piles. Stockpiles will be designed to minimize erosion from
wind and water.
When small disturbances occur on sloped areas, topsoil and spoil piles will require
special placement. Spoil piles will be located uphill of the disturbance to prevent
surface water contamination, and to retain any pile losses within the disturbance
area. When possible, spoil piles will be placed on or near disturbed ground. Topsoil
piles will be located downhill of the disturbance so that any translocation of the
topsoil from the stockpile will be away from the disturbed area.
