Draft Environmental Impact Statement for Roca Honda Mine

Chapter 2. Alternatives, Including the Proposed Action
stockpiles to prevent mass movement and protected from storm water runoff. If the material is
inert, it would be returned to the mine and used to backfill areas for stability during mining.
Alternatively, if the analytical results indicate that acid producing or other toxic constituents
could be leached, the material would be loaded in haulage trucks and taken offsite for disposal.
Runoff from these stockpiles would be collected in storm water retention ponds. The water would
be pumped to the onsite water treatment plant before it is discharged. The bottom sediment from
the ponds would be analyzed for constituent makeup and disposed of appropriately in an offsite
facility. Thus, any material with the potential to release acid or other toxic drainage would not be
on the permit area after reclamation (RHR, 2012).
Sufficient material has been identified to restore a vegetative community that would support the
approved post-mining land use of livestock grazing. Topdressing that has been stockpiled for
more than 1 year would be analyzed to determine if soil amendments are necessary to support
successful reclamation of disturbed areas. RHR commits to the addition of mycorrhizal inoculum
for all topsoil materials stockpiled at depths greater than 2 feet from the surface.
As part of reclamation operations, disturbed areas would be stabilized through grading areas to
conform to the geomorphic character of the region and surrounding area, including shaping,
berming, and grading to final contour. Reclamation of slopes would incorporate the practice of
minimizing slope lengths and gradients, while conforming to the geomorphic character of the
region and surrounding areas to minimize the potential for excessive erosion. Both runoff and
runon (water entering a site) would be diverted from reclaimed areas to prevent erosion of those
areas. The reclaimed slopes would be protected using best management practices (BMPs) to
reduce erosion into these diversion channels. If a channel has the potential to erode into a
reclaimed slope, the bank would be armored temporarily until the reclamation project has been
approved. The reclaimed areas would be monitored for erosion until stabilization and
revegetation has been achieved. Any areas of major erosion discovered during this monitoring
would be repaired, stabilized, and revegetated (RHR, 2012).
With regard to revegetation, salvaged topdressing would be redistributed over regraded areas,
amended with mycorrhyzae and organic fertilizers, and then seeded using native, adapted species
characteristic of the region and supportive of livestock grazing. The proposed seed mix in table 2
is used at the nearby Lee Ranch Coal Mine, which has similar topography, soils and climatic
regime. It has shown to be effective over more than 30 years, and is a mixture of cool and warm
season species of grasses, forbs, and shrubs that have demonstrated ability to reestablish in mine
reclamation soils and also to support livestock grazing. All species are known for their
palatability to livestock and wildlife, are high in nutritive value for native plant species, and have
differing seasonal value between species, which makes the mix supportive of the post-mining
land use of grazing on a year-round basis (RHR, 2012).
DEIS for Roca Honda Mine, Cibola National Forest 49