Draft Environmental Impact Statement for Roca Honda Mine

Chapter 3. Affected Environment and Environmental Consequences
Impacts to wildlife from habitat fragmentation are associated with the destruction or modification
of habitat or with the introduction of a permanent disturbance to the habitat that serves to divide
large areas of continuous habitat (USFS, 2011). Habitat fragmentation can isolate wildlife
populations, decreasing population productivity. Construction of roads, utility corridors, and
surface facilities could create wildlife barriers and alter migration patterns and species dispersal
(Al-jabber, 2003). Habitat in the region has already been fragmented from previous mining
operations (drill pads and access roads) and rangeland activities. BMPs would be used to
minimize these impacts. When large pipelines are laid on the ground, wildlife “ramps” would be
constructed across the pipeline at about 300-foot intervals. Culverts would be placed on grade
wherever possible to allow animal passage (RHR, 2009c).
Fragmentation could impact smaller ground-dwelling animals because they may also have to go
around the mining operation to locate forage or living space. Long-term adverse effects to
wildlife from habitat loss, degradation, and fragmentation could range from minor to major in
magnitude and would be medium in extent, probable, and slight in precedence. Major impacts
would occur if the RHR mine violated the MBTA. These impacts could be avoided by
implementing timing restrictions on habitat removal from April 1 to July 31, but during initial
construction this may not be feasible.
Both action alternatives would entail installation and operation of the 20-inch diameter, 6-milelong
water reuse pipeline, which would be laid atop the ground surface. However, this connected
action would not result in long-lived habitat loss, alteration, degradation, or fragmentation.
Nonetheless, some short-term habitat degradation in the immediate vicinity of the line would be
expected as a result of running and using equipment and vehicles off-road atop vegetation.
Although the 20-inch diameter, aboveground line could conceivably interfere with movement and
migration of small mammals, reptiles, and nonwinged insects, it is likely that imperfections
(bumps and depressions) on the ground surface would in fact allow these small animals to pass
beneath the pipeline relatively unobstructed.
Displacement
Impacts to wildlife from noise and associated visual disturbance could result in the temporary
displacement of some species during mine development, operation, and reclamation including
blasting and excavation activities. It could also occur while the water reuse pipeline is being laid.
Noise can adversely affect wildlife in two ways: by inducing stress and by masking
communication and other natural sounds (USFS, 2011). Animals rely on meaningful sounds for
communication, navigation, avoiding danger, and finding food. Noise pollution is defined as any
human sound that alters the behavior of animals or interferes with their daily functions (FHWA,
2011). The level of impact from noise on wildlife depends on decibel levels, durations, and the
physical characteristics of the environment (Ouren et al., 2007). Noise pollution can harm the
health, reproduction, survivorship, habitat use, physical distribution, abundance or genetic
distribution of wildlife (FHWA, 2011). Noise can also lead to changes in behavior, including
avoidance behavior and changes in normal patterns (Radle, 1998).
Development and/or operation noise and disturbance from human activity would continue until
the completion of reclamation activities. Noise impacts could also impact the ability of wildlife to
use vocal communication and natural sounds important for mate attraction, social cohesion,
predator avoidance, prey detection, navigation, and other basic behaviors (USFS, 2011). Impacts
232 DEIS for Roca Honda Mine, Cibola National Forest