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Next, suitable subsoil will be salvaged (average depth of 16 inches) depending on the specific
soil conditions encountered. Salvage depths will be determined based on test pits excavated
during a preconstruction survey. Suitable soil encountered at lower depths will be stockpiled as
necessary to provide an adequate volume of soil for reclamation.
Unsuitable subsoil will be added to excess material/spoil piles (namely the Waste Rock Facility)
and will not be used for revegetation. All practical precautions will be taken to avoid mixing the
unsuitable soil with the suitable topsoil and subsoil. WDEQ-LQD Guideline No. 1, Topsoil and
Overburden provides the parameters, analytical procedures, and suitability criteria for topsoil
and subsoil evaluation. The radiological criteria for topsoil stockpile and replacement is the
natural background concentration of the soil material. According to WDEQ Guideline No. 1,
topsoil may consist of the A, B, and C soil horizons or any combination thereof and which has
been determined through soil surveys, laboratory analyses, and field trials to be suitable as a
plant growth medium for post mining land use. Soil is unconsolidated mineral material in the
immediate surface of the earth that serves as a natural medium for the growth of plants and
differs from the material from which it was derived in many physical, chemical, biological, and
morphological properties and characteristics.
Subsoil may contain any subsurface earthen materials, excluding any material within the topsoil
layer, which is capable of supporting plant life.
Soil Storage.
The topsoil and subsoil stockpile locations will be flagged before beginning
earthworks (see Map 4.2-2 – map pocket). Suitable topsoil is assumed to be stockpiled in two
locations: (1) within the PUG Plant Site and north of the PUG Plant, and (2) east of the Waste
Rock Facility. Suitable subsoil will be salvaged and stockpiled separately but in similar locations.
Each stockpile will be marked with signs designating it as “Topsoil for Revegetation” or “Subsoil
for Revegetation.” Unsuitable soil will be placed in the Waste Rock Facility or used to balance
cut/fills associated with construction. The excess material/spoil stockpile will be clearly marked
with a sign designating it as “Unsuitable for Revegetation.”
Soil stockpiles will be constructed with slopes no steeper than 3H:1V. Surface runoff will be
diverted away from the stockpiles. Suitable topsoil and subsoil stockpiles will be seeded to
provide erosion protection, discourage weed invasion, and maintain microbial populations.
Soil Stabilization.
Appropriate measures will be applied to prevent wind and water erosion
using short- and long-term soil stabilization techniques. The following soil stabilization
techniques will be used when appropriate:
No surface disturbing activities will occur when soils are wet or frozen.
Apply appropriate compaction during placement of soil.
Manage storm water run-on and control storm water run-off to prevent erosion.
Dozer-track all fill slopes immediately after construction.
Properly place and compact berms.
Promptly seed, mulch, and revegetate.
Monitor and repair erosional features.
Use a soil tackifier where appropriate.
5.22.4.2 Revegetation
Surface Preparation.
Existing, in-place materials will first be spread to conform to pre-
disturbance contours to the extent practical in all areas to be reclaimed. After regrading, a disk,
harrow, or scarifier will be used to alleviate compaction and provide a roughened contact for
redistributed topsoil.
