2021-01-14_PERMIT FILE - C1981019A ‎(3)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 1/14/2021
• Section_Exhibit Name: 2.05 Operations and Reclamation Plans
• Media Type: D
• Archive: Yes

RULE 2 PERMITS
the estbalishment of reclaimed plant communities that meet the designated post mining land use
of rangeland, with the subcomponents of grazingland and wildlife habitat. Please see Section
2.05.5 for a detailed description of the post mine land uses at Colowyo.
Areas designated as grazingland for the post mining land use will aim to establish vegetation
communities comprised of species primarily selected for palatability and production, with
incidental wildlife habitat. The reclamation seed mixes utilized in grazingland targeted areas are
designed to establish highly productive stands of native perrennial grasses to support grazing and
forage, yet the mixes contain forbs and shrubs to also provide additional benefits for incidental
wildlife use. Topsoil replacement depths in grazingland areas vary based on slope, which will
encourage species diversity and mimic soil development processes in native soil systems.
Areas designated for wildlife habitat as the post mining land use will aim to establish a sagebrush
steppe vegetation community.The reclamation seed mix utilized in sagebrush steppe targeted areas
is designed to encourage sagebrush establishment by decreasing perennial grass competition
through decreasing the number of grass species and seed numbers, and also incorporating only
bunchgrasses (as opposed to sod-forming grasses), with a significant increase in the total amount
and relative proportion of sagebrush seed. Reclamation techniques that will encourage the
deposition and entrapment of blowing snow (to increase spring soil moisture) are also employed
in sagebrush steppe targeted areas,to provide a competitive advantage to sagebrush over perennial
grasses. These techniques include taking advantage of site-specific opportunities for the
development of convex and concave surfaces along with the potential development of small berms
along the contour and approximately perpendicular to prevailing winds. Topsoil replacement
depths in sagebrush steppe targeted areas will be reduced relative to other areas, also to decrease
competition from grasses.
The reclamation timetable and associated acreages for the various aspects of the mining operation
are provided on Table 2.03-1.
Backfill and Grading Plan
As discussed in detail in Section 2.05.3, the mining method implemented by Colowyo is referred
to as open-pit multiple seam/single seam dragline mining. The overburden material from the initial
boxcut area was deposited in a permanent valley fill. As mining progresses, overburden material
from each successive cut is backfilled into the previously mined out area. This cycle was repeated
for the entire mining area. Because an open-pit mining technique is used, the regrading and
backfilling of the spoil material is as contemporaneous as possible behind the mined-out area to
facilitate proper leveling of the overburden material.
The backfilled mining areas are graded to establish the approximate original contour and to blend
in with the undisturbed areas outside the mining limits. Additional information on the backfilling
and regrading plan are discussed further in Section 2.05.3 and Section 4.14.
Final grading before topsoil placement will be conducted in a manner that minimizes erosion and
provides a surface for the topsoil that minimizes slippage. If spoil compaction is a problem, the
Rule 2 Permits 2.05-17 Revision Date: 10/27/20
Revision No.: TR-143