REP35525

• Permit No: M1978305
• IBM Index Class Name: Report
• Doc Date: 5/18/2004
• Doc Name: Environmental Assessment
• From: Nat. Park Service
• To: DMG
• Media Type: D
• Archive: No

Im act To is Issue Statement s
Geology and Soiis The mining and removal of decomposed granite and intermixed materials
would result in the loss of geologic materials and soil productivity on up to
31.94 acres and could cause geohazards from high walls and unstable
slopes.
• The release of hydrocarbons or other contaminating and hazardous
substances from vehicles and equipment could alter the chemical and
physical properties of the soil in the vicinity of the operations. Changes in
soil properties could result directly from contact with contaminants on site or
indirect) via runoff from contaminated areas.
Vegetation Mining, processing, and transporting decomposed granite and intermixed
materials would result in the loss of vegetation on up to 31.94 acres. Loss
of vegetation could alter wildlife habitat and species composition, increase
stormwater runoff, and increase erosion.
• The release of hydrocarbons and contaminating or hazardous substances
could damage or kill vegetation directly via contact with contaminants on
site or indirectly via pathways from contaminated areas.
• Disturbances/removal of native vegetation could lead to the unintentional
spread and establishment of non-native plant species already within the
disturbed areas of the pit as well as those transported in or on drilling and
maintenance a ui ment.
Wildlife The mining, processing, and transporting of decomposed granite and
intermixed materials (including blasting, vehicle use, processing, and
removal of mined materials) could result in increased predation in adjoining
undisturbed areas; directly harm or kill wildlife; and disrupt wildlife feeding,
denning, nesting, spawning/reproduction, and other behavior. The mining
operations would result in the continued avoidance of the area by wildlife
due to increased noise and human presence.
• Loss or modification of wildlife habitat would occur from the expansion of
the mining operation. These activities could alter the nature of the habitat
between the pit and the surrounding lands, increase human access, and
alter wildlife species, composition, and migration.
• Elevated noise from occasional blasting activity, crushing and screening,
and loading trucks with mined materials could affect wildlife in close
proximity to the pit.
• stormwater that may collect and drain from the pit could attract, harm, and
possibly kill wildlife.
• The release of hydrocarbons and hazardous or contaminating substances
from vehices and equipment could injure wildlife. The adverse effects
could become worse over time if wildlife species ingest the contaminants
and are consumed b other wildlife s ecies.
Species of . Elevated noise from occasional blasting activity, crushing and screening,
Management Concern and loading trucks with mined materials could affect peregrine falcons,
ferruginous hawk, or swift fox that could be nesting in or using areas in
close proximity to the pit.
• Mining operations, including vegetation removal, could adversely affect the
Gunnison milkvetch or Rollin's twin od state im eriled 5 ecies .
Archeological • Expanding the mining operation into an area where a National Register of
Resources Historic Places-eligible archeological site is located would result in the loss
of the archeolo ical resources if not mitt ated.
Visitor Use and . The mining operation could pose a threat to human health and safety from
Experience geohazards, elevated noise levels, use of large equipment and vehicles
(particularly from vehicles with less maneuverability and visibility), and
vehicular traffic conflicts on access roads.
The mining operation could adversely affect air quality, alter scenic
resources, increase background sound levels, and could degrade the
_ _ _ _ _ _ quafit+Lof visitor uses and experiences in the park. _
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