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Implementation of rapid stabilization practices for disturbed areas to reduce erosion and
the movement of sediment. Techniques such as the application of organic mulches on
disturbed slopes may also increase the efficiency and effectiveness of future
revegetation efforts.
Implementing physical technologies for stabilization, especially on steep slopes where
erosion is excessive. Practices such as surface scarification, placement of silt fences,
cross-slope barriers constructed of straw bales, and the use of surface coverings such
as nettings or plastic coverings may be used as-needed to control the movement of
sediment down slopes.
Recovering the uppermost soil horizon from the Waste Rock Facility foundation during
construction and stockpiling it for use in revegetation. This practice will be used in
conjunction with the establishment of a short-term vegetation cover, consisting of fast-
growing plant species, for the protection of the stockpiles against erosion. Containment
berms will be constructed around and/or downstream from topsoil stockpiles.
Implementation of rapid revegetation techniques for disturbed areas where practical,
especially on constructed elements such as road cuts and fills, borrow areas, and rock
and other disposal areas. The vegetation will be seeded prior to the onset of the next
growing season in order to prevent excessive loss of material. Local vegetation species
that grow rapidly may be used in order to maximize the development of a self-sustaining
vegetative cover. Such a mix could contain species such as Canada wildrye (
Elymus
canadensis
), thickspike wheatgrass (
Elymus lanceolatus
), western wheatgrass (
Elymus
smithii
), slender wheatgrass (
Elymus trachcaulus
), and applicable, commercially
available bluegrasses or fescues. A vegetative cover protects the surface against
erosion and provides long-term stabilization of the area. RER will consult with the Forest
Service to determine a desirable seed mix.
Maintenance of erosional features will be conducted until long-term surface stabilization
is achieved. Annual maintenance may include repairing and seeding erosional features
such as rills and gullies that develop on newly revegetated slopes, recontouring problem
slopes, and the installation of additional channel protection in natural drainage channels
located downgradient of sediment control structures, if erosion is evident.
5.4
SOLID WASTES
Solid wastes generated at the Mine generally fall into three categories: waste rock (overburden)
that is removed to access the ore; waste created on-site (e.g., septic tank wastes from the
offices, change house, warehouse, and other facilities, truck wash wastes, laboratory wastes,
and spill cleanup residues – if spills occur); and waste from purchased materials (e.g., shop
wastes, oil and grease, and non-hazardous trash). Descriptions of these waste streams and
handling plans for disposal are provided below.
5.4.1 Waste Rock
Over the life of mine, 123.7 million tons of waste rock will be generated and will be placed in the
Waste Rock Facility with a footprint of approximately 426 acres. The Waste Rock Facility
(located in Section 16 on private lands) and just east of the Mineable Pit will accommodate
waste rock from the Bull Hill Resource Area, Whitetail Resource Area, and High Grade oxide
reject. The design includes 2.5 horizontal to vertical lift faces that will be reclaimable. These
faces will be developed from an angle of repose approximately 1.4 horizontal to vertical faces by
dozing after active placement on a face is completed. Low grade reject material (13.7 million
tons) will be placed in the Low Grade Ore Stockpile (approximately 70 acres) located within the
