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4.1.5.3. Impacts of the Proposed Action on Wildlife

4.1.5.3.1. Impacts on Wildlife Habitat

In addition to other changes, this section has been modified from the November 1996 Draft EIR in response to comments to increase the off-site land acquisition compensation ratio for disturbed microphyll woodland habitat from 1:1 to 3:1.

The total area of surface disturbance resulting from Project construction and operation within the Project mine and process area would be 1,302 acres. This would include approximately 1,215 acres of desert scrub habitat and approximately 87 acres of microphyll woodland habitat. The loss of wildlife habitat, particularly the loss of microphyll woodland habitat, would directly or indirectly displace resident birds within or near the Project mine and process area. The Project would also result in an incremental loss of foraging habitat for wildlife and/or migratory species such as bats and raptors. The effects of the loss of habitat from the Project on wildlife would continue over the life of the Project, and some of the effects would continue for an extended period following final reclamation. Wildlife would eventually return to the Project mine and process area as vegetation reestablishes and disturbed surfaces are reclaimed or recover. However, the projected period before conditions return to an approximate pre-Project status with respect to wildlife carrying capacity may exceed several decades following completion of the active life of the Project (Rado 1997). To compensate for this reduction in carrying capacity, the Proposed Action contains many measures (which are also contained in Mitigation Measures 4.1.5-7 through 4.1.5-26) to reduce the impacts on microphyll woodland habitat and associated wildlife which use this habitat; reduce the long-term impacts of the Proposed Action; provide off-site compensation for these habitat losses; and enhance reclamation. These are each discussed below, as is the level of significance for each.

As discussed in Section 3.5.6, the CDFG considers microphyll woodland to be a sensitive habitat. It is considered second only to riparian habitat in wildlife diversity in the desert area, and it is considered a particularly important habitat component to deer and other wildlife species (Personal Communication, Nancy Andrew, CDFG, 1996). CDFG has a policy of requiring replacement of habitat "on-site" and "in kind" when possible for wetland habitat impacted as a result of proposed projects. This means that sensitive wetland habitat lost within a proposed project area as a result of proposed project activities would be required to be replaced by the project applicant with the same type and quality of sensitive wetland habitat somewhere within the project area when possible, or outside of the project area when on-site replacement is not possible. Wetland habitat would not be impacted by the Imperial Project, but the CDFG also adapts this wetland habitat policy to other habitats which they consider sensitive, such as microphyll woodland, when evaluating measures to mitigate the biological effects of projects which may require Stream Alteration Agreements (Personal Communication, Lilia Martinez, CDFG, 1996).

Surface disturbance from the Imperial Project would result in the destruction of approximately 87 acres of microphyll woodland habitat within the Project mine and process area. Based on the work done at the Picacho Mine, it is apparent that microphyll woodland vegetation can be re-established (Bamberg and Hanne 1997; see also Attachment B to Appendix A, Reclamation Plan). The estimated time for recovery of a microphyll woodland, that is, for establishment of trees and shrubs to a density approaching the natural wash vegetation, is estimated at five (5) years; for recovery to a condition approaching maturity is estimated at twenty (20) years. Plant succession and changes in structure would continue for approximately 50 years for trees (up to 30 feet). The expected survival of ironwood seedling transplants after one (1) year, based on Picacho experience (December 1995 to December 1996), is approximately 80 percent (Bamberg and Hanne 1997). Studies are underway on ironwood propagation at the Picacho Mine working in conjunction with the Desert Legume Program at the University of Arizona. Other typical wash plant species (palo verde, brittle bush, saltbush, sweetbush, desert mallow, wire lettuce, and annual grasses and forbs) have been successfully grown from seed collected in washes (Bamberg 1997b; see Appendix G).

Measures are incorporated into the Project design to minimize the area of microphyll woodland habitat disturbed by the Project to 87 acres and to mitigate the adverse effects of the Project on microphyll woodland habitat. Reclamation measures would result in reestablishment within the Project mine and process area of approximately one-half (2) of these 87 acres of disturbed microphyll woodland habitat. Additional Project measures intended to compensate for the loss of microphyll woodland habitat from the Project include providing for the acquisition of off-site private lands containing microphyll woodland habitat at a ratio of 3:1 for all of the acres of microphyll woodland habitat disturbed within the Project mine and process area, reclamation of previously disturbed public lands not associated with the Proposed Action to be identified and approved by the BLM (see Section 4.1.5.4).Vegetation, wildlife and ecosystem processes are also expected to benefit from off-site compensation of upland habitat for desert tortoise and microphyll woodland habitat. Compensation lands that are in close proximity to the Project mine and process area, of equal or better habitat quality, and of similar vegetation community, elevation, hydrology, wind patterns, and substrates, would provide the greatest benefit. Additional measures to mitigate and compensate for the impacts of the Proposed Action on the ephemeral stream channels and associated microphyll woodland habitat are provided in the required Stream Alteration Agreement between the Project Applicant and the CDFG. A draft Stream Alteration Agreement has been prepared and is currently under negotiation between the CDFG and Glamis Imperial (Glamis Imperial 1997; see Section 4.1.5.4). With the implementation and success of these measures proposed as a part of the Proposed Action or required by regulation, the effect of the Proposed Action on microphyll woodland habitat within the Project mine and process area would be below the level of significance.

Diversions of the major surface drainages through constructed channels around the Project facilities would continue to provide the same flow and quality of water into these major wash systems downgradient of the Project mine and process area as exists prior to mine construction. No substantial impact on wildlife habitat or species in the major wash system downgradient of the Project mine and process area is expected. Similarly, wildlife habitat in the Algodones Sand Dunes foothill "pockets" of microphyll vegetation downgradient of the mine would not be affected by the Project. Although some minor, ephemeral tributaries of the major channels would be "truncated" by the construction of the waste rock stock piles and the heap, thereby reducing the amount of water which may flow into these small tributary channels, the amount of reduction in water flow in the major channels would be imperceptible and would not result in any significant effects.

The through-flowing surface drainages would be located as close to their original courses as reasonably possible in comparably-sized channel(s) which would tie into the original wash systems downgradient of the diversion point. As discussed in Section 4.1.5.2, these diverted drainages would be revegetated with microphyll vegetation to reestablish microphyll woodland habitat. However, as a result of Project construction, the affected microphyll woodland habitat in the smaller drainages which are not diverted cannot be reestablished within the Project mine and process area, and thus there would be a net reduction of microphyll woodland habitat in the Project mine and process area as a result of the Project. However, with implementation of the elements of the Proposed Action to compensate for the permanent loss of microphyll woodland habitat within the Project mine and process area, this loss would be less than significant.

As discussed in Section 3.5.6, approximately 2 acres of microphyll woodland habitat within the Project ancillary area and approximately 1 acre of microphyll woodland habitat in the overbuilt 92 kV/34.5 kV transmission line corridor are expected to be impacted by surface disturbance associated with the Proposed Action within these areas. The proposed removal of Project facilities and the other reclamation activities contained in the Proposed Action to be completed as part of final reclamation within the affected portions of the Project ancillary area and the overbuilt 92 kV/34.5 kV transmission line corridor are expected to fully reclaim the disturbed microphyll woodland habitat in these two (2) areas. These impacts would be below the level of significance.

Several small, isolated, ephemeral water seeps located northwest to southwest of the Project ground water well field area, in the vicinity of or adjacent to the Algodones Sand Dunes, likely provide seasonal water and habitat for wildlife which is otherwise limited in this region. As indicated in Section 3.3.1, because Project ground water production would be from a different aquifer than these seeps, it would not impact the shallow source of the seeps, and would not impact biological resources which may be supported by these seeps.

4.1.5.3.2. Impacts on Wildlife and Wildlife Movement

Wildlife species which inhabit, move through, or forage within the approximately 1,340 acres of surface area to be disturbed within the Project area would be subject to increased mortality or displacement as a result of the Proposed Action. Increased mortality would result from direct physical impacts or entombment during construction or processing activities, or result in indirect mortality from stress or increased predation pressure resulting from displacement into off-site areas. Individual animals could also be subject to injury or mortality during on-site blasting and continued mining operations and geological survey activities, and increased mortality from project-related stresses, including night lighting, in the vicinity of the Project mine and process area. Noise-sensitive species would be expected to avoid both the Project area and neighboring areas over the life of the Project, but would be expected to return when noise generating operations are discontinued. Similarly, species intolerant of surface disturbance and human activities would also be expected to avoid the Project area and neighboring areas over the life of the Project. Because of the substantial amount of alternative habitat available, these impacts to wildlife and wildlife movement are not considered significant.

Some wildlife species might come under increased pressure from opportunistic predators (i.e., ravens, coyotes and kit foxes) attracted to the Project area by increased water availability, refuse, or noise. In addition, during the life of the Project the movements of some wildlife through the Project mine and process area would be restricted as a result of the perimeter fence, the constructed Project features (such as the pits, waste rock stockpiles, and heap), or the general level of human presence and activity. Because of the substantial open space surrounding the Project mine and process area, these effects are not considered significant.

Over the life of the Project, additional injuries and mortality to wildlife would be expected to result from direct impacts with motor vehicles commuting to the Project area and other equipment traveling to and from the Project mine and process area and the ancillary area. Experience in other remote areas suggests that measures to reduced speeds on public roads, such as posting reduced speed limits, to minimize inadvertent vehicle impacts with wildlife are impractical to enforce. Individual animals attracted to the Project area from available water sources in the area may also be injured or killed by vehicles on the roads inside the Project mine and process area and in the Project ancillary area. The realignment of a portion of Indian Pass Road and creation of new roads to ancillary facilities would create a temporary impact on the movement of wildlife in the area, particularly for mule deer, coyotes, foxes, and badgers. These species are expected to acclimate to the new roads, but there may be some permanent displacements and readjustments of home ranges, even though the road realignment and ancillary area access roads are temporary. These impacts to wildlife and wildlife movement from roads and vehicles are not considered significant.

Wildlife could be affected by the hazardous chemicals used by the Project. There would be a potential for impacts to wildlife due to the transport of hazardous chemicals to the Project area via public highways and access roads. The probability of hazardous chemical spillage occurring due to a transport accident is considered low, but the potential for occurrence cannot be entirely eliminated. The preventative and corrective measures discussed in Section 4.1.12.3 would reduce both the potential risk of and effects to wildlife resulting from spills of hazardous chemicals being transported to the Project area to below the level of significance. Wet liners on ponds could attract shorebirds because they mimic wetland shores, which could result in injury or death from the ingestion of toxic chemicals in the ponds. Individual animals could also be subject to drowning in mine process fluid impoundments and increased mortality from exposure to process chemicals within the solution ponds. The Proposed Action includes measures to prevent wildlife from entering process ponds, and the residual effects would be below the level of significance.

The natural tinajas and wildlife guzzlers installed to provide artificial sources of water would not be affected by the ground water withdrawal at the Project ground water well field area, and the wildlife supported by these water sources would not be affected.

An existing section of 34.5 kV transmission line would be overbuilt with a 92 kV/34.5 kV transmission line, and a new transmission line would be constructed along Indian Pass Road, to provide electrical power to the Project mine and process area. Temporary and short-term impacts on wildlife and wildlife movement would occur during pole placement and line stringing activities as a result of minor surface disturbance and human presence. The transmission lines could also increase the availability of potential perch sites for bird predators in the area, which could result in an increase in predatory pressure on wildlife species comprising the prey base for predatory birds in the area. The transmission lines would also increase the potential for collisions or electrocutions of raptors and other bird species. However, all of these impacts would be below the level of significance.

The Proposed Action would result in the excavation of three (3) open pits, two (2) of which would be backfilled with waste rock. The East Pit would remain as an open approximately 198-acre excavation which would remain as a slight long-term impediment to the movement to some wildlife species. Individual terrestrial wildlife species could become injured or killed by falls within this open pit, although as part of the Proposed Action a rock rubble barricade would be constructed around the open pit to prevent vehicular access and limit pedestrian and wildlife access, and haul roads within the open pit would be regraded such that wildlife or humans would still be able to use them to exit the open pit should they pass beyond the barricade. Ground water could accumulate in the bottom of the open pit and form a pit lake, although this is not likely, and measures are incorporated as part of the Proposed Action to reduce the possibility further. Although any water in a pit lake would not be injurious to wildlife (see Section 4.1.3.2.2), wildlife species coming to drink could be exposed to predators which may use the pit area as a place to wait for prey. The Proposed Action also includes measures to offset the net reduction of habitat as a consequence of the open pits. The effects of the Proposed Action on general wildlife species and wildlife movement would be below the level of significance.

If mining is suspended or terminated prior to backfilling of the West Pit, the West Pit would remain as an open excavation and would remain as a long-term impediment to the movement to some wildlife species. Individual terrestrial wildlife species could become injured or killed by falls within this open pit. Ground water could accumulate in the bottom of the open West Pit and form a pit lake, although this is not likely, and measures are incorporated as part of the Proposed Action to reduce the possibility further. Although any water in a pit lake would not be injurious to wildlife (see Section 4.1.3.2.2), wildlife species coming to drink could be exposed to predators which may use the pit area as a place to wait for prey. These effects of the open West Pit on general wildlife species and wildlife movement would be above the level of significance.

4.1.5.3.3. Impacts to Threatened or Endangered Wildlife Species

One species listed on both federal and California threatened species lists, the desert tortoise, would be directly impacted by the Project. Two (2) other currently listed or proposed wildlife species (peregrine falcon and Gila woodpecker), which were either documented during the surveys or previously recorded in the Project area, are also discussed below, but would not likely be impacted by the Proposed Action.

Desert tortoise: The habitats within the Project area are unclassified by the BLM with respect to desert tortoise, and the Project area has not been designated critical desert tortoise habitat by the USFWS (USFWS 1990). However, as a result of field survey documentation of the tortoise within the Project area, the Project area would be considered Category III tortoise habitat (BLM 1989). The number of desert tortoise currently present within the Project area has been estimated from review of the survey data to range between 33 and 57 individuals (Rado 1997).

Desert tortoise which occupy the Project mine and process area may be injured or killed as a result of surface disturbance during Project construction or processing activities. The surface modification activities would occur over approximately 1,302 acres and would destroy the tortoise burrows or pallets within the Project mine and process area, potentially crushing or entombing individuals. Additional tortoises may also be injured or killed as a result of heavy equipment traffic within the Project mine and process area and from impacts with vehicles commuting to and from the Project area on existing or relocated roads. Tortoise occupying areas adjacent to the Project mine and process area, or having home ranges overlapping the Project area, would be similarly affected if they wandered onto the active Project areas. A total of 1,137 acres of desert tortoise habitat within the Project mine and process area would be reclaimed. Adjacent tortoise populations may slowly recolonize this area as vegetative processes establish native habitats. A total of 165 acres, comprising the East Pit slopes, would be lost within the Project mine and process area as desert tortoise habitat after completion of Project final reclamation.

Activities and facilities ancillary to the Project mine and process area and the overbuilt 92 kV/34.5 kV transmission line corridor could also adversely affect desert tortoises. Tortoises could be injured or killed as result of construction of the ground water wells, water pipeline, or electrical transmission line within the Project ancillary area, or the constructions of the overbuilt 92 kV/34.5 kV transmission line. The water pipeline would be buried, so it would not restrict tortoise movement. Construction of the new or overbuilt transmission lines may also attract, or provide perches for, tortoise predators (i.e., ravens). Tortoise populations have been dramatically reduced in areas with higher than normal raven populations. Ravens eat juvenile and hatchling tortoises and can severely reduce recruitment to the tortoise populations. Storage ponds within the Project mine and process area or other sources of standing water and refuse could also serve to attract and increase tortoise predator populations in the vicinity of the Project area.

Following completion of mining activities, individual desert tortoises could wander into the open East Pit. While pit slopes (estimated at 50 degrees) may allow for the movement of animals, individual tortoises could become injured or killed as a result of falls or excessive predation from coyotes, kit foxes, or other species.

Desert tortoises within the Project area would also be subject to displacement either by capture and removal of individuals to locations outside the Project area, or by individuals within or near the Project area voluntarily leaving the vicinity when Project activities are initiated.

Guzzlers constructed in the vicinity of the Project area to mitigate the effects of the Project on wildlife could inadvertently trap desert tortoise and result in increased desert tortoise mortality.

Some design elements have been incorporated into the Project to minimize the effects of the Project on desert tortoise. However, prior to any additional mitigation, the effects of the Project on desert tortoise are considered significant.

Peregrine falcon: No peregrine falcons were observed during surveys of the Project area, but a few falcons have previously been recorded from the Project area. Similarly, the species has been unreported in surveys for other projects in the general area (Condor 1991, WESCO 1992; Office of Arid Lands Studies 1993; Western Resource Development 1993; BLM 1994a). Peregrine falcons are known to nest in cliff areas along portions of the Colorado River system (USBR 1996). No potential nesting sites for peregrine falcons occur in the Project area or the surrounding area. The species could potentially utilize the Project area, including the Project mine and process area, for foraging on an infrequent basis although, based on the absence of prior records, this seems highly unlikely. Project effects on the American peregrine falcon would not be significant.

Gila Woodpecker: A single Gila woodpecker was observed perched on a large ironwood tree in a large wash near the southwest corner of the Project mine and process area by a biologist in January 1995 (Rado 1995). Additional searches for this and other Gila woodpeckers were subsequently conducted but did not record the bird in the Project area. The single observation of the Gila woodpecker is believed to have been of a transient bird. The Gila woodpecker is a cavity nester known to prefer mature cottonwood and willow trees within riparian habitats not present in the Project area. The effects of the Project on the Gila woodpecker would be below the level of significance.

4.1.5.3.4. Impacts to Other Wildlife Species of Concern and Habitat

In addition to other changes, this section has been modified from the November 1996 Draft EIR in response to comments to: discuss the impacts to bats on the basis of the results of a survey of the Project mine and process area for bats; discuss the impacts to flat-tailed horned lizards on the basis of the results of a survey of the southernmost end of the overbuilt 92 kV/34.5 kV transmission line corridor for flat-tailed horned lizard or sign; provide additional assessment on Project impacts on desert deer and bighorn sheep; and discuss the effects of Project lighting on wildlife.

In addition to the listed species discussed above, the Proposed Action may adversely effect the following wildlife species of concern.

Cheeseweed owlfly: The cheeseweed owlfly has not been documented within the Project mine and process area. Since the Project occurs within the geographic range of this species, and because its host plant (creosote bush) is present, the cheeseweed owlfly could potentially occur here. If present, the cheeseweed owlfly would be subject to habitat loss associated with initial blading and grading activities. Additionally, individual cheeseweed owlflies could be attracted to night lighting during operations; although, the species is considered a poor flyer (USBR 1996). The geographic range of this species is extensive and collecting sites widely dispersed. The short flight season of adults and the indeterminate timing of adult emergence may reflect the paucity of records. Therefore, information necessary to determine the effects of the Proposed Action on the cheeseweed owlfly is unavailable. There is no substantial evidence that the Proposed Action would substantially affect the cheeseweed owlfly or its habitat; therefore, impacts would be below the level of significance. Mitigation measures (see Section 4.1.5.4) have been incorporated into the Project design to further reduce the long-term impacts of the Project on potential cheeseweed owlfly habitat.

Chuckwalla: Marginal quality chuckwalla habitat exists over approximately one-half (2) of the Project mine and process area. A total of three (3) chuckwallas were observed during surveys of the Project mine and process area, and an estimated 25 individual chuckwallas may inhabit the Project area (Rado 1995). Chuckwallas are known to display high site fidelity and would not be expected to flee the area as a result of disturbance. As such, the chuckwallas present within the Project area could be killed or injured as a result of surface disturbance associated with mine construction and ore extraction and processing. Chuckwalla habitats are known to exist in the vicinity of Peter Kane Mountain north, Picacho Peak east, and the Cargo Muchacho Mountains south of the Project area. A large portion of the chuckwalla habitat exists within the Indian Pass Wilderness Area and Picacho Peak Wilderness Area. While the effects of the Project on the chuckwalla and chuckwalla habitat would be below the level of significance, measures have been proposed to further reduce the impacts of the Proposed Action on this species (see Section 4.1.5.4).

Flat-tailed horned lizard: There were no flat-tailed horned lizards observed within the Project area during the biological surveys of the area, and no flat-tailed horned lizard habitat exists within the Project area. Likewise, there were no flat-tailed horned lizard or flat-tailed horned lizard sign observed during the specific survey for the flat-tailed horned lizard, along the southernmost portions of the 34.5 kV transmission line to be overbuilt for the Project. Flat-tailed horned lizard habitat does exist south of Interstate Highway 8 in the proximity of the tap (origin) for the overbuilt 92 kV/34.5 kV transmission line, but Interstate Highway 8 provides a permanent barrier which would prevent lizard crossings and potential impacts to the lizard and lizard habitat south of the highway during construction of the overbuilt 92 kV/34.5 kV transmission line.

There have been no recorded sightings of flat-tailed horned lizard within ten (10) miles of the Project mine and process area and Project ancillary area. However, there is a potential that a small number of flat-tailed horned lizards may be injured or killed as a result of Project-related traffic traveling along an approximately one-mile section of flat-tailed horned lizard habit located immediately north of the junction of Ogilby Road and Interstate Highway 8. The results of the flat-tailed horned lizard surveys indicate any impacts to individual flat-tailed horned lizards or its habitat would be below the level of significance.

Loggerhead shrike: Loggerhead shrikes were frequently observed throughout the Project area during the biological surveys (Rado 1995). Shrikes are common and widely distributed in the area. Two (2) family groups were observed within the Project area during the spring breeding period, suggesting a high likelihood that nesting occurs within the Project area, but no loggerhead shrike nests were encountered during the surveys. Based on a projected density of one loggerhead shrike per 50 acres, as was observed in the alluvial plain bordering the Santa Rosa Mountains, an estimated 33 shrikes may currently use the Project area for foraging and/or nesting. During construction and mining activities within the Project area, approximately 1,340 acres of shrike habitat would be disturbed, displacing shrikes to neighboring unmodified lands. Individual loggerhead shrike nests may be destroyed, resulting in mortality to nestling birds or abandonment of eggs if disturbance occurs during the spring breeding period. Because of the availability of substantial off-site shrike habitat, the effects of the Proposed Action on the loggerhead shrike and shrike habitat would be below the level of significance.

Black-tailed gnatcatcher: Black-tailed gnatcatchers were observed within the Project area during the biological surveys. Favored gnatcatcher areas appeared to be in secondary drainages with wash vegetation in which young ironwood and palo verde trees provide cover (Rado 1995). Gnatcatchers utilizing the Project mine and process area would be displaced to neighboring unmodified lands. Individual black-tailed gnatcatcher nests would be destroyed, resulting in mortality to nestling birds or abandonment of eggs if surface disturbance occurs during the breeding period. Because of the availability of suitable gnatcatcher habitat in neighboring areas, the effects of the Proposed Action on the black-tailed gnatcatcher and its habitat would be below the level of significance.

Sharp-shinned hawk: A single sighting of a sharp-shinned hawk occurred in the Project area during the biological surveys (Rado 1995). This species is reported to be an uncommon winter migrant through the area. Implementation of the Project would result in a small reduction of the regional foraging habitat available to migrating sharp-shinned hawks, and it could result in a minor behavior modification of individual birds that cross the Project area. Based on the low frequency in which sharp-shinned hawks are projected to utilize the Project area, and the availability of off-site foraging habitat, the effects of the Proposed Action on the sharp-shinned hawk and its habitat would be below the level of significance.

Northern harrier: Two (2) sightings of northern harriers were made within the Project area during the biological surveys (Rado 1995). The sightings were during the fall and were attributed to isolated birds presumed to have been migrating through the area. There is no northern harrier nesting habitat within the Project area. The Project would result in a small reduction of the regional foraging habitat available to migrating northern harrier, and it could result in a minor behavior modification of individual birds that cross the Project area. Based on the low frequency in which northern harrier are projected to utilize the Project area, and the availability of substantial off-site foraging habitat, the effects of the Proposed Action on the northern harrier and its habitat would be below the level of significance.

LeConte's thrasher: LeConte's thrashers were not recorded during the biological surveys, which included playing recorded bird calls during the breeding season in an attempt to elicit a response. However, prior records suggest that LeConte's thrashers may occur within the Project area (CNDDB 1996; BLM records). If present, the species would be subject to habitat loss, displacement of individuals to off-site areas, and possible disruption of breeding and nest failure. Because of the availability of substantial off-site thrasher habitat, the effects of the Proposed Action on LeConte's thrasher and its habitat would be below the level of significance.

Crissal thrasher: A single crissal thrasher was observed within the Project mine and process area during the surveys. The species is closely associated with drainages and wash "edge" vegetation. A total of about 87 acres of such habitats would be affected by Project actions. Crissal thrashers that utilize these drainages would likely be displaced into adjacent unmodified lands as a result of conversion of habitat. Depending upon timing of year, nests may also be abandoned, resulting in mortality of nesting birds and/or abandonment of eggs. Because of the availability of substantial off-site crissal thrasher habitat, the effects of the Proposed Action on the crissal thrasher and its habitat would be below the level of significance.

Vaux's swift: Vaux's swifts utilize the general area, including the Project area, during spring and fall migration. They do not nest in this region. Development may result in minor behavioral modification of migrating birds passing through the region. Mining activities would also result in a reduction of the available foraging/resting habitats for migrating birds. Because of the availability of substantial off-site swift foraging/resting habitats, the effects of the Proposed Action on the Vaux's swift and its habitat would be below the level of significance.

Golden eagle: Golden eagles were not observed during the biological surveys. Eagle nesting sites are also absent from the Project area and vicinity. The species may utilize the general area, including the Project mine and process area, for foraging. Project construction and operations within the Project area would result in the incidental loss of 1,340 acres of potential golden eagle foraging habitat. Based on the widespread availability of off-site foraging habitat for golden eagles, the effects of the Proposed Action on this species and its habitat would be below the level of significance.

Prairie falcon: Biological surveys did not document the occurrence of the prairie falcon. However, the prairie falcon has been previously recorded within the general area and could utilize the Project area and surrounding area for foraging (BLM records). Project construction and operation activities within the Project area could result in the loss of 1,340 acres of foraging habitat for prairie falcons. Based upon widespread availability of off-site foraging habitat, the effects of the Proposed Action on this species and its habitat would be below the level of significance.

Cooper's hawk: Biological surveys did not document the occurrence of the Cooper's hawk. However, the species has been recorded as a seasonal visitor in the general area and could utilize the Project area and surrounding area for foraging (BLM records). Project construction and operation activities within the Project area could result in the loss of 1,340 acres of foraging habitat for Cooper's hawk. Based on the widespread availability of off-site foraging habitats for Cooper's hawk, the effects of the Proposed Action on this species and its habitat would be below the level of significance.

Long-eared owl: Biological surveys did not document the occurrence of the long-eared owl. However, the species has been recorded as a seasonal visitor in the general area and could utilize the Project area and surrounding area for foraging (BLM records). Based on the widespread availability of off-site foraging areas for long-eared owls, the effects of the Proposed Action on this species and its habitat would be below the level of significance.

Barn owl: Natural caves, fissures, old mine tunnels and shafts, or abandoned buildings often used for barn owl nesting are not present within the Project area. Project development would potentially result in the creation of barn owl nesting within storage sheds, maintenance buildings, or other "open" structures. Since this species has been recorded in the general area (BLM records), Project operations within the Project area would result in the potential reduction of 1,340 acres of barn owl foraging habitat. Based on widespread availability of off-site foraging habitat for barn owls, the effects of the Proposed Action on this species and its habitat would be below the level of significance.

Yuma puma: No pumas or sign were documented during surveys of the Project area. Use of the Project area by deer, a primary prey species for pumas, suggests that mountain lions may occur in the general area. Unconfirmed sightings of mountain lion in the region have been conveyed to the CDFG by hunters (Personal Communication, Rusty McBride, CDFG, 1996). Mine construction and operation activities would result in the reduction of 1,340 acres of foraging habitat potentially available to mountain lions. Associated impacts to deer could also incrementally affect the prey base for mountain lions. Based on the widespread availability of off-site foraging habitat for mountain lions, the effects of the Proposed Action on this species would be below the level of significance.

American badger: Badgers are presumed to utilize the Project area for foraging, but the actual number of badgers that may use the area is indeterminate. Previous studies of the species reported individual badgers having home ranges of 1,400 and 2,100 acres (Messick 1987). Based on the area of these home ranges, few American badgers would be expected to occupy habitat within the Project area. The Project would result in a reduction of the habitat available to badgers in the Project area, and increased noise, lighting, and traffic would likely result in behavior modifications by badgers to avoid the area. Based on the availability of off-site foraging habitat, the effects of the Proposed Action on the American badger and its habitat would be below the level of significance.

Sensitive bat species: No sensitive bat species were recorded within the Project mine and process area during the original biological surveys (Rado 1995). No mine adits, caves, or large rock crevices exist in the Project area, thereby limiting the species of bats which may day roost within the Project mine and process area. However, some bat species could roost in trees or in small rock crevices. A survey of the Project mine and process area for bats was conducted by Patricia E. Brown, Ph.D. in June 1997 (see Section 3.5.6.2). Five (5) sensitive bat species designated by the USFWS as Special Status Species and/or California species of concern (CSC) could conceivably roost, and also forage, in the Project area, including: Yuma myotis, small-footed myotis, cave myotis, occult little brown bat, and desert pallid bat. An additional six (6) Special Status Species/CSC bat species would not roost in the Project area but could use the Project area as nighttime foraging habitat, including: Townsend's big-eared bat, spotted bat, western mastiff, California leaf-nosed bat, big free-tailed bat, and pocketed free-tailed bat.

Large numbers of bats would neither be killed nor displaced by the Project. Foraging habitat would be affected, but similar habitat is widespread around the Project area. Night lighting from the Project would attract insects and could result in a net increase in bats foraging in the vicinity of the Project mine and process area. This could lead to individual bat collisions with lights or drownings in ponds. However, based on the availability of off-site day roost areas and foraging habitat, the effects of the Proposed Action on sensitive bat species and their habitat would be below the level of significance.

Mule deer: Desert deer are widely distributed throughout the Project area and surrounding area, but the deer population is reported to be low (Celentano and Garcia 1984). Deer were observed to use the northeast-southwest trending wash channels as movement corridors and to also move cross-gradient over the upland areas and across the washes in the Project area.

The Proposed Action would impact deer habitat by eliminating the use of the Project mine and process area by deer over the life of the Project, until habitat is reestablished, and would permanently eliminate the majority of the open East Pit from deer habitat. Project-related impacts to deer habitat could result in a slight net reduction in the numbers of deer that seasonally utilize the Project area, and/or that may reside in the Project area due to the availability of water in maintained guzzlers located south and also east of the Project mine and process area. Potential impacts to deer and deer habitat would include:

• The general loss of most of the Project mine and process area as foraging habitat during the life of the Project, and in particular the loss of the approximately 87 acres of microphyll woodland habitat which would be destroyed during Project construction.
• To the extent the Project mine and process area serves as deer fawning habitat, the approximately 87 acres of microphyll woodland in the washes would be destroyed as potential fawning habitat during Project construction.
• Restricted access through the Project mine and process area as a result of fencing may limit deer movement in the vicinity of the Project mine and process area. Access to three (3) big game guzzlers located east and south of the Project mine and process area boundaries would be slightly reduced.
• Noise from equipment operation, blasting activities, and human presence, as well as night lighting of the Project mine and process area facilities, would be expected to inhibit deer activity in the immediate vicinity of the Project mine and process area in the short-term; however, deer would be expected to acclimate to Project noise over time and resume utilization of the areas outside the boundaries of the Project mine and process area (Personal Communication, Nancy Andrew, CDFG, 1997).
• Vehicles commuting on roads to the Project mine and process area would increase the potential for vehicle impacts with deer and resulting injuries and mortality. If the Project results in an approximate five (5) percent increase in traffic (see Section 4.1.11.1.2), then a proportional potential increase in traffic-related deer mortality (i.e., an increase from approximately two (2) percent to 2.1 percent) would be expected to result.
• Deer which penetrate the perimeter fence and/or process fence of the Project mine and process area would be subject to an increased potential for vehicle impact injuries and mortality and ingestion of potentially harmful process pond solutions or other chemicals stored and used within the Project mine and process area.
• Realignment of Indian Pass Road could impact migration routes, dispersal corridors and deer movement. Deer are expected to acclimate to the road realignment; however, there may be some permanent displacement.
• Water could accumulate in the East Pit (or West Pit, if not sufficiently backfilled) and attract deer to the new water source, altering the habitat for deer. Limited access to and from the pit(s) could potentially serve as an opportunity for increased predation of deer.
• Deer may become stressed if they get into the Project mine and process area, and this could reduce fawn production in does.

Because of the low density and scattered distribution of deer in the area, and the relative abundance of similar habitat in the vicinity of the Project area, the Proposed Action would not be expected to directly or indirectly impact a large number of deer. Some deer would be indirectly impacted by reduction of habitat quality through vegetation removal. Given conflicting professional opinion as to the importance of the Project area and vicinity for deer use and as fawning habitat, the specific significance of the impacts of the Proposed Action on deer and deer habitat without the implementation of those measures designed into the Proposed Action to reduce the impact and compensate for the adverse effects on microphyll woodland habitat is uncertain. However, with the implementation of these measures, impacts to deer and deer habitat are below the level of significance. Elements of the Project design which would mitigate impacts on deer include (see also those measures identified under the applicable heading in Section 4.1.5.4):

• Constructing a 6-foot high, barbed-wire topped, chain-link fence around all Project-created surface water sources within the Project mine and process area, including the heap leach pad, process facilities, and fresh water pond;
• Revegetating disturbed areas following mining activities, and including native deer forage plants as a part of this effort (subject to BLM and CDFG approval);
• Performing revegetation within the permanent diversion channels, including direct transplanting of microphyll species from disturbed drainages, planting of young seedling palo verde and ironwood and seeding with species common to the microphyll woodland habitat;
• Performing revegetation on selected adjacent drainages subject to historic damage unrelated to the Proposed Action;
• Directing diverted surface drainages back into the same major channels to maintain continuity of flow and water quality to habitat downstream of the Project mine and process area;
• Constructing a rock barrier around the remnant East Pit and back filling the pit to a level above any predicted pit lake, if necessary;
• Constructing three (3) off-site big game guzzlers at a location in the vicinity of the Project area mutually agreeable to the Applicant, the CDFG and the BLM; and
• Constructing one or more on-site big game or small game guzzlers at the conclusion of final reclamation.

Desert bighorn sheep: No bighorn sheep were observed within the Project area during the biological survey, and the Project area is not within established bighorn habitat. Natural dispersal corridors, between Peter Kane Mountain to the north and the Cargo Muchacho Mountains to the south, lie several miles to the east of the Project mine and process area, and these routes would not be directly affected by the Project activities. Although noise from Project operations, especially from blasting, may be discernable in these areas, the effect on bighorn sheep would be below the level of significance. The Project facilities may impact movement of bighorn sheep rams between mountain ranges; however, this direct route is not considered a substantial movement corridor and the impact of the Project on desert bighorn sheep movement would be below the level of significance.

4.1.5.4. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

The following measures have been incorporated into the Project design to reduce the impacts to plant and wildlife species and habitat during the active life of the Project.

• 4.1.5-1: Applicant shall construct a fence around the entire Project mine and process area. The fence shall be constructed no less than four (4) feet in height with 3-strands of smooth wire, or equivalent. That portion of the perimeter fence constructed along the western boundary of the Project mine and process area, including all of the fenceline adjacent to Indian Pass Road (see Figure 2.2), shall be a chain-link fence, no less than six (6) feet in height, to restrict public access to the Project mine and process area. The entire perimeter fence shall include desert tortoise exclusion fencing, in conformance with responsible agency requirements, to inhibit tortoise access to Project facilities (see also Mitigation Measure 4.1.5-40). Applicant shall construct a chain-link fence, no less than six (6) feet in height, with one (1) foot of barbed wire at the top, around the ore leach pad, process facilities, and fresh water pond to further restrict wildlife from accessing these facilities. Applicant shall routinely inspect and repair the fences, as necessary. Applicant shall document any deer or other wildlife mortalities observed within the Project mine and process area, shall monthly report such mortalities to the BLM and the CDFG, and shall work with the BLM and CDFG to implement additional or amended measures to reduce the mortalities. A field contact representative (FCR) shall be responsible for maintaining the records of perimeter fence inspections and repair, and shall have authority to direct the repair of damaged or destroyed fences. The FCR may be a project manager, company environmental coordinator, contract biologist, or other person identified as responsible by the Applicant.
• 4.1.5-2: Applicant shall prohibit cross-country use of vehicles and equipment except within those portions of the Project mine and process area subject to surface disturbance.
• 4.1.5-3: Applicant shall cover the pregnant and barren solution ponds with either small-mesh nets; a solid, 40-mil, HDPE/polypropylene cover; floating plastic balls; or equivalent cover acceptable to the BLM to keep wildlife out of the ponds. Applicant shall maintain the cover over the life of the Project. Applicant shall keep records of all wildlife kills which may be associated with the use of cyanide by the Project, including all dead wildlife found in or adjacent to the ponds or heap. Individual threatened and endangered species found dead on the Project mine and process area shall be sent for necropsies. Observations of wildlife killed in the ponds or on the heap shall be reported to the BLM, CDFG, and the U.S. Fish and Wildlife Service (USFWS) monthly for evaluation and, if determined necessary, for possible imposition of additional mitigation requirements.
• 4.1.5-4: Applicant shall advise Project employees, contractors, and visitors of the need to adhere to speed limits and to avoid any animals, including the desert tortoise, flat-tailed horned lizard, and deer which may be encountered on or crossing roads to and from the Project area. Applicant shall also require Project employees, contractors, and visitors to report all incidences of wildlife injury or mortality resulting from Project-related vehicle traffic on roads used to access the Project to the FCR, who shall monthly report these incidences to the BLM and the CDFG. Applicant shall participate in agency efforts to reduce mortality of wildlife on the roads used as access to the Project when so requested by the BLM.
• 4.1.5-5: Prior to completion of mining, Applicant shall conduct an assessment of the potential for a pit lake to form in the East Pit. If the assessment indicates a reasonable potential for a pit lake to form, Applicant shall backfill the East Pit to an elevation higher than the level of any pit lake which may be predicted to form from the inflow of ground water and, thereby, prevent the creation of an attractive nuisance for wildlife. The findings of the pit lake assessment shall be completed and submitted for approval by the BLM prior to the completion of mining activities. Applicant shall monitor open pit areas monthly during the duration of post-mining reclamation for any evidence of the formation of a pit lake. The results of this monitoring shall be reported monthly to the BLM. Should the BLM determine that the monitoring indicates that a pit lake is forming or may form, the Applicant may be required to conduct an additional study or place additional backfill material into the bottom of the East Pit.
• 4.1.5-6: Before removal of the perimeter fence at the end of the active life of the Project, Applicant shall regrade haul roads within the open pit such that wildlife or humans may still use them to exit the residual open pit should they pass the barricade around the rim.

The following additional measures have been incorporated into the Project design to reduce the impacts on microphyll woodland habitat and associated wildlife which utilize this habitat.

• 4.1.5-7: Applicant shall construct a fence, no less than four (4) feet in height with 3-strands of smooth wire, or equivalent, around the approximately 40-acre south-central portion of the central wash internal to the Project mine and process area which is not intended to be disturbed by Project operations to prevent accidental surface disturbance of the microphyll woodland habitat in this area during mine construction and operation.
• 4.1.5-8: Applicant shall provide periodic slug irrigation to enhance the establishment of ironwood and deer browse vegetation within the surface drainage identified by Mitigation Measure 4.1.5-7 to enhance the quality of habitat and provide established deer browse which would be immediately available at the end of the active life of the mine. Vegetation selected for enhanced deer browse establishment shall be comprised of species known to occur in the Project area. The irrigation shall be reduced and then ceased once the vegetation is established. The composition of the seed mix and the design of the vegetation enhancement measures shall be submitted to the CDFG for approval prior to implementation.
• 4.1.5-9: Applicant shall construct and maintain during the life of the Project three (3) big game guzzlers in a design and location acceptable to the BLM and the CDFG in the general vicinity of the Project mine and process area to provide for more intensive use of the existing habitat by deer and other wildlife. Within one (1) year of approval of the ROD, the Applicant shall have either: provided sufficient funds to a third party (acceptable to BLM and CDFG) which shall construct, own, and operate the guzzler; or completed construction of the guzzler. Applicant or the acceptable third party shall obtain the required permits from the BLM prior to guzzler construction. The guzzler shall remain after reclamation.
• 4.1.5-10: Applicant shall provide periodic slug irrigation to enhance the establishment of ironwood and deer browse vegetation along the western slopes and banks of the approximately 3,000-foot section of the existing ephemeral stream channel immediately adjacent to, but outside of, the east-southeast boundary of the Project mine and process area. Vegetation selected for enhanced deer browse establishment shall be comprised of species known to occur in the Project area. Supplemental watering shall only be conducted for the first few years to allow the plants to become established. Water shall be reduced over a period of time to enable the plants to acclimate to natural moisture conditions. The composition of the seed mix and the design of the vegetation enhancement measures shall be submitted to and approved by the CDFG prior to implementation.
• 4.1.5-11: Applicant shall conduct annual transect surveys in the spring season of the ephemeral washes which flow out of the Project mine and process area, the principal washes which flow into the Project mine and process area upstream of the Project mine and process area to serve as a control, and the undisturbed ephemeral washes within the Project mine and process area, for the purpose of determining if Project construction and/or operations are having an indirect adverse effect on microphyll woodland habitat not directly impacted by surface disturbance. The surveys shall document the diversity, density, and cover of the vegetation directly associated with the washes, and shall include observations regarding the general "health" of the vegetation. The surveys shall also document any observations regarding sediment transport processes within the washes any incidental sightings of deer fawn, bighorn sheep, bobcat, kit fox, mountain lion, or other species specified by the BLM. An annual report of the results of the surveys shall be prepared and submitted to the BLM and CDFG in a form acceptable to the BLM. If, as a result of these surveys, microphyll woodland habitat downstream of the Project mine and process area is determined to be adversely impacted by the Project, appropriate additional mitigation measures may be required by the BLM and shall be implemented by the Applicant. BLM may require the Applicant to acquire title to off-site private lands with comparable microphyll woodland habitat, in a location acceptable to the BLM and the Applicant, to compensate at a 3:1 ratio for adverse impacts to microphyll woodland habitat not otherwise compensated for which cannot be mitigated through application of these additional mitigation measures.
• 4.1.5-12: Applicant shall construct all stream channel diversions to divert flows back into the same major wash system and ensure the continuing flow of an equivalent pre- and post-Project quantity of water through the major drainages to preserve the downstream microphyll woodland habitat within the drainages (see also Mitigation Measure 4.1.5-15 and mitigation measures provided for surface hydrology in Section 4.1.3.1.3).
• 4.1.5-13: Applicant shall implement the Project Reclamation Plan in conformance with the requirements of the BLM and Imperial County. The Reclamation Plan shall include a program for revegetation of the permanent diversion channels, including the planting of seedlings of young ironwood and palo verde at a density approximating that of the displaced washes and seeding of the pre-Project wash habitat (see also Mitigation Measure 4.1.5-17). The transplanted seedlings shall be protected from browsing or trampling by wire cages for the first two (2) years and from excessive sun by shade material, if necessary, or native nurse plants, if available and necessary, to facilitate transplant success.
  
  Microphyll woodland vegetation within the permanent diversion channels shall be established during early mining operations and managed and monitored throughout the life of the Project. Applicant shall conduct annual transect surveys in the spring season of the diversion channels for the purpose of determining revegetation success. The surveys shall document the diversity, density, and cover of the vegetation directly associated with the washes, and shall include observations regarding the general "health" of the vegetation. An annual report of the transect surveys shall be prepared and submitted to the BLM, Imperial County and CDFG in a form acceptable to the BLM and Imperial County. Should the surveys indicate that the revegetation of the diversion channels may not meet the standards required by the approved Reclamation Plan, the BLM and Imperial County may require appropriate additional revegetation measures to be implemented by the Applicant.
  
• 4.1.5-14 Applicant shall construct and maintain as a part of final reclamation, one or more big game and/or small game guzzlers within the Project mine and process area in a design and location acceptable to the BLM and the CDFG to enhance the area as habitat for deer and other wildlife. Final Project reclamation bond(s) shall not be released until either: the Applicant has provided sufficient funds to a third party (acceptable to BLM and CDFG) which shall construct, own, and operate the guzzler(s); or the Applicant has completed construction of the guzzler(s). Applicant or the acceptable third party shall obtain the required permit from the BLM prior to guzzler construction. The guzzler(s) shall remain after reclamation. The guzzler(s) shall be designed and constructed in a manner which allows desert tortoise to readily exit the guzzler(s).
• 4.1.5-15: Project actions would require the realignment of sections of washes. Applicant shall develop a specific plan for approval of the BLM that ensures maintenance of intermittent flood water flow down these realigned wash channels into unmodified drainage boundaries outside of the Project in order to preserve vegetation and wildlife habitat. Design of these sections of realigned wash shall also include appropriate dimensions and slopes to accommodate continued use by wildlife during mining operations and to facilitate revegetation. A specific plan shall be prepared by Applicant and submitted to the ICPWD and BLM for review, and approval of the BLM, prior to the onset of any activities that would result in disturbance to these drainages. Plan design shall include the vegetation of channel diversions with native species that include ironwood and palo verde in order to maintain continuity of washes and enhance wildlife habitat, in conformance with the approved Reclamation Plan. Unless explicitly directed otherwise by the BLM (in consultation with the CDFG), all diversion channel lining materials and rip rap shall be removed from the diversion channels.

The following measures have been incorporated into the Project design to reduce the long-term impacts of the Project on plant and wildlife habitat and to enhance reclamation of plant and wildlife habitat.

• 4.1.5-16: Upon completion of mining activities, Applicant shall remove all equipment and materials from the Project area. Unless explicitly directed otherwise by the BLM (in consultation with the CDFG), all diversion channel lining materials and rip rap shall be removed from the diversion channels and any necessary reclamation completed by the Applicant, consistent with the approved Reclamation Plan.
• 4.1.5-17: The Project Reclamation Plan shall include the collection of both fairy duster seeds and winged cryptantha seeds and distribution of the collected seeds of both species within appropriate microhabitats within the Project mine and process area. During Project operations, the Applicant shall experiment with the seeds (and transplants if reseeding is not successful), of both species to assure plant success and survival. Recovery of these two (2) species shall be considered successful when species density meets or exceeds the criterion set forth in the Approved Reclamation Plan.
• 4.1.5-18: Applicant shall stockpile available soil from the wash channels to be disturbed within the Project mine and process area and store the soil for subsequent use during reclamation activities. Soil stockpiles shall be located away from washes and other areas prone to erosion and consolidated as appropriate to reduce disturbance to undisturbed areas within the Project mine and process area. Stockpiles shall be kept shallow and dry, if not to be used within one (1) year of initial placement, to protect seeds entrained in the soil.
• 4.1.5-19: Applicant shall salvage specimens of selected plant species from the Project mine and process area prior to construction to be utilized during habitat enhancement activities or other Project reclamation needs. Plant species may include cactus, ocotillo, ironwood, palo verde, or other appropriate species identified by the BLM.
• 4.1.5-20: Applicant shall implement weed control measures such that all introduced plants (e.g., salt cedar (tamarisk species), mustard, and other noxious weeds) will not become established within the Project area. Manual or mechanical means of control shall be the preferred methods employed. Use of other methods (e.g., herbicides) shall require approval by the BLM. The weed control measures shall be implemented within six (6) months of when noxious weeds are visually identified within the Project area and shall continue over the life of the Project. Tamarisk species shall be actively controlled throughout the life of the Project by eradication of any seedlings or growth observed. If tamarisk is determined to be a continuing problem after the completion of reclamation, a portion of the reclamation bond in an amount determined appropriate by the BLM and Imperial County shall be retained to fund an eradication program to eliminate factor(s) conducive to tamarisk growth (e.g., moist areas).
• 4.1.5-21: Applicant shall implement the revegetation program contained in the Project Reclamation Plan approved by Imperial County and the BLM. The revegetation program shall include a test plot program, surface contouring and shaping, salvage and distribution of stockpiled soils, collection of a seedbank of seeds from within and in the vicinity of the Project area, preparation of seedbeds, seeding with approved mixtures of native plant species endemic to the area, planting of the plants salvaged from the area prior to mine construction, monitoring for invasion of noxious weeds or salt cedar, and vegetation success monitoring. The standards for revegetation success shall be specific to each vegetation type and based on reasonably achievable results that shall provide a plant cover and density sufficient to support long-term revegetation. Final bond release shall occur when the vegetation success criteria set forth in the Reclamation Plan have been met and the reestablishment of vegetation is confirmed.
• 4.1.5-22: Applicant shall integrate the revegetation program activities with other stabilization and reclamation activities required by the approved Reclamation Plan (see also Mitigation Measures 4.1.5-12 and 4.1.5-13).
• 4.1.5-23: Access roads which are created, or any other areas which are disturbed for the construction of the transmission line, pipeline, and well field, shall be reclaimed when they are not needed for ongoing maintenance. Reclamation methods shall include regrading, surface preparation, and revegetation either through seeding or natural processes.
• 4.1.5-24: To compensate for those lands not reclaimed within the East Pit, Applicant shall perform reclamation activities on one or more off-site locations on land in the vicinity of the Project acceptable to Applicant and the BLM, as appropriate, to reclaim habitat which has been adversely impacted by previous actions unrelated to the Project.
• 4.1.5-25: Applicant shall repair any detected leak in the water pipeline along Indian Pass Road as soon as reasonably possible in order to prevent tamarisk invasion and eliminate an attractive nuisance to wildlife.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.5-26: Applicant shall enter into a Stream Alteration Agreement with the California Department of Fish and Game (CDFG) as required pursuant to California Fish and Game Code Section 1603 which shall contain those measures which CDFG and Applicant agree may be necessary, or appropriate, to mitigate, and compensate for, the impacts of the Project on the stream channels and associated microphyll woodland habitat and wildlife. The October 31, 1997 draft of the Stream Alteration Agreement for the Imperial Project includes the following substantive requirements, which are subject to modification until agreed to by both parties:
  
  (1) "For impacts to approximately 90 acres of microphyll woodlands, the Operator shall mitigate, through the purchase of off site lands, at a 3:1 ratio. The location of the mitigation area shall be subject to review and approval of the Department. The mitigation lands shall be deeded to the Department."
  
  (2) "The Operator shall install and maintain for the life of the project, three (3) big game guzzlers at locations tp be approved by the Department. One additional guzzler shall be installed within the off-site mitigation land addressed ... above. One guzzler will also be constructed within the project site prior to final reclamation."
  
  (3) "As addressed within the DEIS/EIR ..., Operator shall; fence the approximately 40 acres contained within the central wash to prevent human intrusion, enhance the surrounding microphyll woodland habitat within the Central Wash area shall be fenced to prevent human intrusion, enhance the surrounding microphyll woodland habitat through various methods, implement and maintain a vigorous exotic and invasive weed control program, maintain all setbacks, berms, and erosion control features within the project."
  
  (4) "In those project areas where active nesting birds occur, the Operator shall flag or stake a minimum of five (5) yards in all directions. This flagged zone shall not be disturbed until the nest becomes inactive, or unless otherwise directed by the Department."
  
• 4.1.5-27: Applicant shall comply with all of the terms and conditions of the Biological Opinion prepared for the Project by the U.S. Fish and Wildlife Service in response to the BLM request for formal consultation pursuant to Section 7 of the Endangered Species Act of 1973, as amended.
• 4.1.5-28: Project actions may require either an individual dredge and fill permit (404 permit) from the U.S. Army Corps of Engineers (ACOE) or one or more Nationwide Permits. Applicant shall obtain the appropriate authorization from the ACOE prior to the onset of any actions that would disturb drainages within the Project area.
• 4.1.5-29: The California Regional Water Quality Control Board, Colorado River Basin Region (CRWQCB ) shall be notified by the Applicant of Project actions, and Applicant shall comply with CRWQCB requirements for obtaining Waste Discharge Requirements and Certification under Section 401 of the Clean Water Act for proposed discharges to land and a general Storm Water Permit.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

The following measures were identified to mitigate the effects of the Proposed Action on the Desert tortoise. These, or similar, mitigation measures, have been required by the Biological Opinions issued by the U.S. Fish and Wildlife Service for nearby projects, including the American Girl Mine, the Mesquite Mine, and the Mesquite Regional Landfill. Each of these measures would be required by the BLM for the Proposed Action:

• 4.1.5-30: Applicant shall designate a field contact representative (FCR) who shall be responsible for overseeing compliance with protective stipulations for listed species. The FCR shall have authority to halt all activities that are in violation of the stipulations. The FCR shall have a copy of all appropriate stipulations when work is being conducted within the Project area. The FCR may be a project manager, company environmental coordinator, contract biologist, or other person identified as responsible by the Applicant. Applicant shall provide the name and contact information of the FCR to the BLM and applicable responsible agencies prior to construction.
• 4.1.5-31: During the life of all Project activities, stockpiling of equipment and vehicles shall utilize only those portions of the Project area that would be subject to permanent disturbance. Temporary or inadvertent disturbance of remaining portions of the area should be minimized by: staking, "flagging," or otherwise clearly marking the boundaries of the alignment; notifying employees of the specific areas, boundaries of the areas, and the need to avoid disturbance to remaining areas; and posting signs or erecting temporary fencing at access points to limit access to authorized vehicles and equipment only.
  
  All employees shall be instructed that their activities shall be confined to locations within flagged or otherwise marked areas.
  
  The area of disturbance shall be confined to the smallest practical area, considering extent and location of ore bodies, topography, placement of facilities and access roads, locations of sensitive species , public health and safety, and other limiting factors. To the extent practical, previously disturbed areas within the Project mine and process area shall be used for the placement of equipment, work staging sites, or parking of vehicles.
  
• 4.1.5-32: Open pipeline trenches, test holes, or test trenches shall be regularly inspected by the FCR, or qualified biologist acceptable to the BLM, a minimum of three (3) times per day. During excavation of trenches or holes, escape ramps consisting of loose earth deposited in the test hole or trench shall be placed to facilitate the escape of any wildlife species that may enter the excavations. Any animals discovered shall either be allowed to escape before activities resume or carefully removed from the pit or trench and allowed to escape. A final inspection of the open trench segment or hole shall also be made by the FCR, or qualified biologist acceptable to the BLM, immediately prior to backfilling. Arrangements shall be made prior to the onset of maintenance or construction to ensure that listed wildlife species can be removed from the trench without violating any requirements of the federal or California Occupational Safety and Health Administration. All test holes shall be immediately capped or abandoned upon completion of drilling to prevent access of wildlife.
• 4.1.5-33: Toxic materials maintained on the Project area shall be stored and used in a manner that prevents harm to desert tortoises and other wildlife species. Methods of containment shall be approved by the BLM.
• 4.1.5-34: Nets or other suitable coverings shall be placed over all ponds containing toxic solutions to prevent contact by area wildlife species, including bats. These coverings shall be regularly inspected and maintained by Applicant for the duration of the Project. Methods of cover, inspection, and maintenance shall be approved by the BLM.
• 4.1.5-35: Project employees involved with regular activities shall be required to take a threatened and endangered species education training program which shall include a discussion of both endangered and threatened species and species that are not endangered or threatened. The program shall include information on the biology of listed, sensitive and unlisted species as well as the desert tortoise, flat-tailed horned lizard, mule deer, big horn sheep, and bats and their occurrence in the Project area. The discussion shall include information on the measures being implemented for the protection of these species and their habitats during Project activities and means by which individual employees can facilitate this process.
  
  A program approved by BLM shall be employed and taught by a qualified individual acceptable to the BLM. Wallet-size cards signifying completion of training shall be issued to employees. All employees shall participate in the education program prior to commencing Project activities. New employees shall receive formal approved training prior to working on-site. The program shall typically last from between one and two hours and shall cover the following topics at a minimum:
  
  • Distribution in general and in the Project area;
  • General behavior and ecology;
  • Sensitivity to human activities;
  • Legal protection;
  • Penalties for violation of State and federal laws;
  • Reporting requirements; and
  • Project mitigation measures.
    
• 4.1.5-36: Incidences of observations of desert tortoises and their sign during activities shall be conveyed to the FCR during all Project activities. Employees shall be notified that they are not authorized to handle or otherwise move any desert tortoises encountered.
• 4.1.5-37: Tortoises commonly seek shade during the hot portions of the day. During mine project activities, employees shall be required to check under equipment and vehicles prior to moving such. If tortoises are encountered, the vehicle shall not be moved until such animals have voluntarily moved to a safe distance away from the parked vehicle.
• 4.1.5-38: If desert tortoises must be moved during any Project activities, the following procedures shall be implemented by persons authorized by the USFWS to handle desert tortoises:
  
  (1) Desert tortoises shall be handled only by an authorized tortoise handler and only when necessary. New latex gloves shall be used when handling each desert tortoise to avoid the transfer of infectious diseases between animals. Desert tortoises shall be moved the minimum distance possible within appropriate habitat to ensure their safety. In general, desert tortoises shall not be moved in excess of 1,000 feet for adults and 300 feet for hatchlings. An authorized tortoise handler should follow the general handling methods contained in the "Protocols for Handling Live Tortoises" (USFWS 1990).
  
  (2) Desert tortoises that are found above ground and need to be moved shall be placed in the shade of a shrub. All desert tortoises removed from burrows shall be placed in an unoccupied burrow of approximately the same size as the one from which it was removed. All excavation of desert tortoise burrows shall be done using hand tools, either by, or under the direct supervision of, an authorized tortoise handler. If an existing burrow is unavailable, an authorized tortoise handler shall construct or direct the construction of a burrow of similar shape, size, depth, and orientation as the original burrow. Desert tortoises moved during inactive periods shall be monitored for at least two days after placement in the new burrows to ensure their safety. An authorized tortoise handler shall be allowed some judgement and discretion to ensure that survival of the desert tortoise is likely.
  
  (3) If desert tortoises need to be moved at a time of the day when ambient temperatures could harm them (less than 40 degrees F or greater than 90 degrees F), they shall be held overnight in a clean cardboard box. These desert tortoises should be kept in the care of an authorized tortoise handler under appropriate controlled temperatures and released the following day when temperatures are favorable. All cardboard boxes shall be appropriately discarded after one use.
  
  (4) All desert tortoises moved shall be marked for future identification. An identification number using the acrylic paint/epoxy covering technique should be placed on the fourth costal scute (USFWS 1990). No notching should be authorized.
  
  To facilitate clearing the area of desert tortoises, excavation of burrows should begin no more than fourteen (14) days prior to the onset of surface disturbing activities, as long as a final survey is conducted within 24 hours of the onset of activities to ensure that desert tortoises have not returned to the work area.
  
• 4.1.5-39: In order to minimize any exposure risk to desert tortoises, a specially designed fence shall be constructed around all portions of the Project area containing pits, ponds, waste rock stockpiles, ore processing areas, maintenance areas, and surface facilities. The final fence design shall be discussed with and found acceptable to the USFWS, BLM, and CDFG. The desert tortoise exclusion fence must meet the following preliminary design specifications:
  
  (1) Fencing shall result in a non-breachable barrier, and its support structure may be comprised of a variety of materials;
  
  (2) Galvanized 2-inch diameter mesh and 36-inch wide hardware cloth shall be used; and
  
  (3) The hardware cloth shall be buried 12 inches underground, extend at least 24 inches above the ground, and be firmly attached to the bottom of the perimeter fence and other wildlife exclusion fences.
  
• 4.1.5-40: Following fence installation, and prior to initiation of mining, authorized biologists under the supervision of an authorized tortoise handler shall conduct a complete (i.e., 100%) survey for desert tortoises within the fenced area. All tortoises found shall be marked and removed from the fenced mine area for safe off-site release within 1,000 feet of the outside of the Project fence using protocols acceptable to the BLM, USFWS, and the CDFG. Prior to release, a total of up to ten (10) of these tortoises (consisting, insofar as possible, of equal sex ratios of adult animals) shall be equipped with radio transmitters, and an equal number of individual additional tortoises (consisting, insofar as possible, of equal sex ratios of adult animals) from the "resident" tortoise population outside of the Project mine and process area shall also be equipped with radio transmitters. For a three-year period, the specific locations of all telemetered tortoise will be rechecked at monthly intervals by the FCR and mapped and recorded. Once each year, an qualified biologist will examine telemetered tortoises and record data relative to the animal's location, movements, health, and any changes noted. Data from these surveys will be used to assess the effects of relocation on both the tortoises relocated from the Project mine and process area and those resident tortoises present within the relocation area.
• 4.1.5-41: At the conclusion of Project pre-activity surveys and the relocation of any desert tortoises outside of the Project fence, Applicant and an authorized tortoise handler shall prepare a summary report documenting the desert tortoise protection measures implemented. The summary report shall be submitted to the BLM.
• 4.1.5-42: Pipeline placement design outside of tortoise-proof fenced project boundaries shall allow for the unimpeded movement of tortoises and other small terrestrial wildlife species.
• 4.1.5-43: That portion of the transmission line corridor extending outside of the fenced Project mine and process area boundary shall be re-surveyed for desert tortoise burrows and pallets within fourteen (14) days preceding line upgrading/construction. Tortoise burrows and pallets encountered within the construction zone (if any) shall be conspicuously flagged by the surveying biologist(s) and avoided during power pole placement or existing line upgrading. Contingent upon the findings of the pre-survey for the transmission line upgrade/construction, a determination shall be made by the BLM as to whether or not on-site desert tortoise monitoring would be required during the transmission line upgrade/construction activities.
• 4.1.5-44: Transmission and distribution pole design shall prevent nesting or perching by ravens, a major predator of young desert tortoises (see also Mitigation Measure 4.1.5-54).
• 4.1.5-45: As an alternative to the use of speed bumps, notification signs for the desert tortoise and speed limit signs shall be placed and maintained within the Project boundary by Applicant to reduce chances for inadvertent vehicle-induced injury or mortality to desert tortoises and other wildlife species. Applicant, with the concurrence of Imperial County, shall also place these signs along Indian Pass Road leading to the Project mine and process area.
• 4.1.5-46: Applicant shall participate in the BLM desert tortoise program for acquiring offsetting lands in compensation for adverse modification of desert tortoise habitat. Under the BLM policy, undesignated lands such as the Project area, where tortoises or tortoise sign are located, become Class III tortoise habitat. Within Class III habitat, an offsetting ratio of 1:1 (e.g., one (1) acre of land secured and protectively managed for each acre affected) is applied. Lands shall be first considered in Imperial County and will include 87 acres of habitat within microphyll woodland.
• 4.1.5-47: For any well field changes or drilling activities subsequently proposed for the Project, Applicant shall comply with the relevant terms and conditions of the Biological Opinion for Small Mining and Exploration Operations in the California Desert, dated June 1, 1992, prepared with respect to desert tortoise by the USFWS, and amended as necessary to be consistent with the desert tortoise protection measures prescribed in the USFWS Biological Opinion for the Project.

The following measures were developed to mitigate the effects of the Proposed Action on wildlife and wildlife movements should mining be suspended or terminated prior to either partial or complete backfilling of the West Pit and Singer Pit:

• 4.1.5-48: Should mining be terminated prior to backfilling of the West Pit above the ground water level, Applicant shall conduct an assessment of the probability of the formation of a pit lake after mining. Any evaluation of the potential for the formation of a pit lake in an open pit shall consider the quantity of surface flow runon and direct precipitation. If the assessment reasonably indicates that ground water encountered in the West Pit may enter the pit in sufficient quantity, considering evaporation, to create a pit lake, the Applicant shall place sufficient backfill into the open portion of the West Pit to raise the floor of the pit to a level higher than the level of any pit lake which the study indicates may form.
• 4.1.5-49: Any pit left open following the completion of mining shall be left in a condition which minimizes the potential for, and quantity of, water which may enter the pit through surface water runon. In addition, the bottom of any pit left open after the completion of mining shall be composed of a layer of loose rubble to minimize the potential for the formation of standing water in the bottom of the pit from either precipitation or surface water runon.
• 4.1.5-50: Before removal of the perimeter fence, Applicant shall regrade haul roads within the open pit(s) such that wildlife or humans may still use them to exit the residual open pit(s).

Other Mitigation Measures (These are measures which may further reduce the impacts of certain effects which are below the level of significance without mitigation):

• 4.1.5-51: A Revegetation and Monitoring Review Committee shall be formed to serve in an advisory capacity to the BLM and Imperial County. The committee shall review the annual vegetation monitoring reports filed by the Applicant for the purpose of interpreting the information contained in the reports, advising the Applicant of actions it might take to improve the success of its revegetation efforts, and advising the BLM and Imperial County as to adjustments which should be made to the revegetation success standards. The composition of the committee shall be proposed by the Applicant and approved by the BLM and Imperial County.
• 4.1.5-52: Chuckwallas shall be moved away from any threats during construction activity and if found within the Project mine and process area during mining operations (approximately 100 meters outside the perimeter fence).
• 4.1.5-53: To prevent the inadvertent electrocution of raptors, unless otherwise agreed to by the authorized officer in writing, transmission and distribution lines shall be constructed in accordance with standards outlined in the publication "Suggested Practices for Raptor Protection on Power Lines" (Raptor Research Foundation, Inc., 1996). The right-of-way holder shall assume the burden and expense of proving that pole designs not shown in this publication are "raptor safe." Such proof shall be provided by a raptor expert approved by the authorized officer. The BLM reserves the right to require modifications or additions to all power line structures placed on these rights-of-way should they be necessary to ensure the safety of large perching birds. Such modifications and/or additions shall be made by the holder without liability or expense to the United States.
• 4.1.5-54: Trash and food items shall be contained in closed containers to reduce attractiveness to opportunistic predators such as ravens, coyotes, and kit foxes.
• 4.1.5-55: Recreational firearms and pet dogs shall be prohibited from the Project mine and process area.
• 4.1.5-56: Applicant shall contact local animal control agents to remove feral dogs that are observed within the Project area.

4.1.5.5. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in the unavoidable loss of approximately 87 acres of tree/shrub vegetation habitat (desert wash microphyll woodland habitat) and approximately 1,215 acres of shrub/scrub vegetation habitat (desert succulent scrub habitat) within the Project mine and process area over the life of the Project. A total of 1,137 acres of this area would be subject to reclamation measures at the end of the Project life to reestablish the vegetation and wildlife habitat, including 33 acres in the bottom of the open East Pit. Approximately 165 acres on the slopes of the East Pit would not be reclaimed, but the Applicant has agreed to reclaim an equal number of acres disturbed by others located outside of the Project area. Approximately 198 acres, comprising the remnant East Pit, would be barricaded to discourage pit access by terrestrial species. Approximately one-half (2) of the disturbed microphyll woodland habitat would be lost and not reclaimed at the completion of reclamation. An additional 36 acres of shrub/scrub vegetation (desert succulent scrub habitat) and approximately 2 acres of tree/shrub vegetation (desert wash microphyll woodland habitat) would be lost within the Project ancillary area; and approximately 21 acres of shrub/scrub vegetation (desert succulent scrub habitat) and 1 acre of tree/shrub vegetation (desert wash microphyll woodland habitat) would be lost within the overbuilt 92 kV/34.5 kV transmission line corridor, although all of this would be subject to reclamation. Resident and non-resident wildlife species dependent on this habitat would be subject to displacement and increased mortality.

The Proposed Action would result in the unavoidable "incidental take" of an estimated 33 to 57 desert tortoises (a federal- and state-listed threatened species) currently occupying the Project area, principally through harassment and some through direct mortality. Mitigation measures are proposed in this EIS/EIR in addition to those of the Proposed Action which would reduce the effects to below the level of significance.

If mining is suspended or terminated prior to backfilling of the West Pit, the West Pit would remain as an open excavation and could produce adverse effects on wildlife. Mitigation measures are proposed in this EIS/EIR which would reduce these effects to below the level of significance.

The mitigated effects of the Proposed Action on biological resources are below the levels of significance.

4.1.6. Cultural and Paleontological Resources

This section is based on the cultural resource report prepared for the area of the Proposed Action by KEA Environmental, Inc. (Pigniolo et al. 1997), which summarizes the results of the ethnohistoric research conducted by Tierra Environmental Services (Baksh 1997). The non-confidential portions of the KEA report are provided as Appendix L of this EIS/EIR. The Tierra report is included as an appendix to the KEA report.

4.1.6.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Disrupt or adversely affect a historic property, including a property with traditional cultural significance (as determined by the NRHP and implementing regulations); or
• Disrupt or adversely affect a significant paleontological site except as part of a scientific study.

Implementation of the Proposed Action would require local and state agencies to demonstrate compliance with CEQA, for which specific guidance regarding cultural resources is presented in Appendix K of the CEQA Guidelines. Federal agencies must demonstrate compliance with the National Historic Preservation Act (Public Law 89-665); 80 Stat 915; 16 USC 470; as amended) [NHPA], which requires actions similar to CEQA for the protection of significant cultural resources. Local agencies may use the NHPA process to demonstrate compliance with CEQA.

Section 106 of NHPA requires a federal agency with jurisdiction over a project to evaluate the effect of the proposed project on properties included on, or eligible for, the National Register of Historic Places (NRHP). Federal agencies must also provide the Advisory Council on Historic Preservation (ACHP) an opportunity to comment on the effects of the proposed project to these properties. The 1992 amendments to the law particularly strengthened Indian Tribe involvement in the process. Specific guidance for these actions are found in federal regulations at 36 CFR Part 800, and in the programmatic agreement between BLM, ACHP, and the California State Historic Preservation Officer (SHPO).

The basic steps in the Section 106 process are:

Step 1 - Identification and Evaluation of Historic Properties (Cultural Resources). Properties within a project's area of potential effect (APE) are identified and, in consultation with the SHPO, evaluated through application of NRHP criteria for eligibility for listing (found at 36 CFR Part 60.4), in conformance with the Secretary of the Interior's Standards and Guidelines for Evaluation (48 Federal Register 44723-44726). The full content of the eligibility criteria are provided as follows:

"The quality of significance in American history, architecture, archeology, engineering, and culture is present in districts, sites, buildings, structures, and objects that possess integrity of location, design, setting, materials, workmanship, feeling and association and:

"A. That are associated with events that have made a significant contribution to the broad patterns of our history; or

"B. That are associated with the lives of persons significant in our past; or

"C. That embody the distinctive characteristics or a type, period, method of construction, or that represent the work of a master, or that possess high artistic values, or that represent a significant and distinguishable entity whose components may lack individual distinction; or

"D. That have yielded, or may likely yield, information important in prehistory or history."

Step 2 - Assessment of Effects. The project's effects on cultural resources listed or determined eligible for listing on the NRHP are assessed through application of the Criteria of Effect found at 36 CFR Part 800.9(a).

­ If no effect is found, the federal agency consults with the SHPO and provides documentation in support of the No Effect Determination. If no objection occurs during a 15-day review and comment period, the project can proceed.

­ If an effect is found, the Criteria of Adverse Effect found at 36 CFR Part 800.9(b) are applied. The results could include: no adverse effect where, while an effect could occur, it would not be harmful to those characteristics that qualify the cultural resource for NRHP listing; or adverse effect where an effect could occur that would diminish the integrity of those characteristics that qualify the cultural resource for NRHP listing.

In the case of the Proposed Action, an Adverse Effect finding is probable. The Area of Potential Effect (APE) contains cultural resources of high religious and heritage significance that cannot be avoided.

Step 3 - Consultation. BLM and the SHPO consult and notify the ACHP, whose participation is optional. The purpose of the consultation is to develop a Memorandum of Agreement (MOA) or to determine that no MOA is needed. Interested parties, including Indian Tribes (as appropriate), are invited to participate in the consultation.

Step 4 - ACHP Comment. The ACHP reviews the MOA and, following the incorporation of proposed changes, accepts and signs it. In the absence of an MOA, the ACHP issues written comments, which BLM considers and then notifies the ACHP of its decision.

4.1.6.2. Impacts of the Proposed Action

In addition to other changes, this section has been substantially modified from the November 1996 Draft EIR in response to comments to: assess the impacts to cultural resources and features identified during the intensive cultural resource resurvey of all areas of potential surface disturbance with the involvement of the Quechan Tribe; and undertake meaningful consultation with the Quechan Tribe and other Native American tribes.

Since no paleontological resources have been found within the Project area, and none are believed present, implementation of the Proposed Action would not have an effect on any paleontological resources, and would produce no significant impacts.

As stated in Section 3.6.2.3, an intensive Class III pedestrian survey and cultural resources inventory of the Project area, the overbuilt 92 kV/34.5 kV transmission line corridor, and additional buffer areas, has been completed. The field investigators evaluated 55 archaeological sites and the Indian Pass-Running Man ATCC as eligible for the NRHP (see Appendix L). The Indian Pass-Running Man ATCC and large multi-component sites in the Project mine and process area are evaluated as eligible under Criteria "A," "C" and "D" (see 36 CFR 60.4). Prehistoric geoglyphs along the overbuilt 92 kV/34.5 kV transmission line corridor are evaluated as eligible under Criteria "C" and "D." Most prehistoric trails are evaluated as eligible under Criterion "D" only, but named trails, those associated with a concentration of cultural features, and those that are particularly well preserved are evaluated as eligible under Criteria "C" and "D". Camp Pilot Knob is evaluated as eligible under Criteria "A" and "D." Ceramic scatters and several other prehistoric sites along the transmission line are eligible under Criterion "D."

Impacts to the cultural resources ultimately determined eligible for the NRHP under criterion "D" would be considered significant unless a treatment program to recover the scientific information and other NRHP-qualifying values of each resource is successfully implemented before the Proposed Action proceeds with the activities which would impact that resource. If cultural resources determined to be significant under Criterion "A," "B" or "C" are adversely affected by the Proposed Action, a determination of adverse effect would need to be made by the BLM, and the resulting impacts would be significant.

Much of the Project mine and process area is expected to undergo direct impacts from excavation of the open pits and construction and operation of the leach pad, waste rock stockpiles, soil stockpiles, diversion channels, haul and access roads, and associated processing and support facilities. The remaining undisturbed acres within the Project mine and process area are principally the throughgoing ephemeral stream channels and isolated areas located between areas of disturbance. Given the intensive nature of the Proposed Action, essentially all of the cultural resources within the Project mine and process area are expected to experience either direct or indirect impacts without special mitigation. Glamis Imperial has adjusted the layout of several Project facilities within the Project mine and process area since November 1996 to avoid direct impacts to certain culturally significant features within the large multi-component sites. The Project mine and process area boundary has been moved and the size of the Project mine and process area reduced to avoid a trail and geoglyph system. One (1) waste rock stockpile and two (2) soil stockpiles have been eliminated, and the configuration of the remaining waste rock stockpiles, soil stockpiles, haul roads, and the heap leach pad have been adjusted to avoid several trails, geoglyphs, and other culturally significant features. However, it is not economically feasible to avoid all of the features that contribute to the significance of these cultural resource sites, and the direct and indirect impacts to these eligible cultural resources within the Project mine and process area would be significant.

Because the entire Project mine and process area is completely fenced, no direct impacts are expected from operations conducted within the Project mine and process area to identified cultural resource sites located outside of the fence. However, indirect impacts to identified cultural resources located adjacent to, but outside of, the Project mine and process area may occur if more intense recreational use occurs in these areas as a result of these uses being excluded from the Project mine and process area. These indirect impacts to eligible cultural resources would be significant.

Project facilities constructed or operated within the Project ancillary area are either narrow, linear features (such as the transmission line, water pipeline, and Indian Pass Road realignments), or features of relatively small surface area (such as the water well pad areas and well pump generator area). Because there is generally more flexibility regarding the actual siting of each of these Project components, avoidance of NRHP-eligible cultural resources within the Project ancillary area is possible, although not completely certain. Indirect impacts to identified cultural resources located adjacent to the Project ancillary area may also occur, either as the result of increased use of these areas by Project workers and service personnel, or if more intense recreational use occurs in these areas. These potential direct and indirect impacts to eligible cultural resources would be significant.

Surface disturbance associated with the construction of the overbuilt 92 kV/34.5 kV transmission line is estimated at a maximum of 22 acres. This consists of redisturbance of many of those areas disturbed during original construction of the 34.5 kV transmission line in the mid-1960's (pole access trails, construction areas, cable pulling stations, etc.) and some new disturbance associated with the pole access trails, pole construction areas, cable pulling stations, and construction staging areas. Because there is substantial flexibility regarding the location of those overbuilt 92 kV/34.5 kV transmission line facilities which produce the new surface disturbance, and because most of the significant cultural features are located in portions of the cultural sites outside of the actual overbuilt 92 kV/34.5 kV transmission line corridor, it is possible, but not certain, that all of the identified NRHP-eligible cultural resources within the overbuilt 92 kV/34.5 kV transmission line corridor would be avoided. However, the direct and indirect impacts of the construction of the overbuilt 92 kV/34.5 kV transmission line on eligible cultural resources would be significant prior to mitigation.

Because of the large size of Camp Pilot Knob (CA-IMP-[TL-35]), complete avoidance of this cultural resource site by construction of the overbuilt 92 kV/34.5 kV transmission line would not be possible. However, relatively little ground disturbance to this property would occur because most of the pole locations are immediately adjacent to the existing Sidewinder Road. Therefore, the field investigators have concluded that the values that make the property eligible for the NRHP would not be adversely affected by the construction (see Appendix L), and thus this would not result in a significant impact. Indirect adverse affects to significant historic cultural resources associated with Camp Pilot Knob located adjacent to the overbuilt 92 kV/34.5 kV transmission line corridor may occur if these properties are incidentally disturbed by transmission line construction workers. This potential indirect impact to this eligible historic cultural property would be significant.

The Indian Pass-Running Man ATCC, including the affected section of the Trail of Dreams, is evaluated as eligible under Criteria "A," "C" and "D." The Project mine and process area cannot avoid impacts to the Indian Pass-Running Man ATCC. According to knowledgeable Quechan representatives, development of the Project would destroy their ability to use the Indian Pass-Running Man ATCC for religious and educational purposes, which would have a "devastating" impact on their cultural heritage. Between fifteen (15) and twenty (20) percent of the Indian Pass-Running Man ATCC would be physically disturbed by the Project mine and process area. The Quechan have stated that construction of the Project would permanently cut-off their ability to use the Trail of Dreams to travel physically and spiritually to the sacred Newberry Mountain. Additionally, because views into and from the Indian Pass-Running Man ATCC contribute to the significance of the Indian Pass-Running Man ATCC, the construction of the waste rock stockpiles and heap would cause a permanent, out-of-character visual intrusion that would severely disrupt cultural use of the Indian Pass-Running Man ATCC. Similarly, solitude is an important contributing characteristic of the Indian Pass-Running Man ATCC, and operation of the Project would cause substantial aural impacts to the Indian Pass-Running Man ATCC. Aural impacts would be long-term, but not permanent, as they would cease upon completion of mining and reclamation. Some of the Project ancillary facilities are also located within the Indian Pass-Running Man ATCC, and would adversely affect the character of the Indian Pass-Running Man ATCC, although to a relatively minor degree when compared to the impact of the Project mine and process area on the Indian Pass-Running Man ATCC. These impacts to the Indian Pass-Running Man ATCC are considered significant.

4.1.6.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.6-1: To reduce Project impacts on identified cultural resources, Project facilities associated with the Project mine and process area shall be located consistent with those presented in the Plan of Operations (Revised September 1997). This shall include all of the Project revisions included since the previous Plan of Operation (Revised October 1996), including the revised boundary of the Project mine and process area, the reduction in the height of the waste rock stockpiles, the elimination of one (1) waste rock stockpile and two (2) soil stockpiles, and the reconfiguration of the remaining waste rock stockpiles, soil stockpiles, haul roads, and the heap leach pad.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

No specific measures.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

• 4.1.6-2: Applicant shall designate a project contact representative (PCR) who would be responsible for overseeing Project compliance with the conditions and stipulations for cultural resources. The PCR shall have authority to halt all activities that are in violation of the stipulations. The PCR may be a project manager, company environmental coordinator, or other person identified as responsible by the Applicant. Applicant shall provide the name and contact information of the PCR to the BLM prior to construction.
• 4.1.6-3: Should previously unidentified cultural resources be discovered during project construction or operations, Applicant shall immediately cease all activities in the immediate vicinity of the discovery and notify the BLM. Activities shall not be reinitiated in the vicinity of the discovery until authorized by the BLM.

The following mitigation measures were identified by KEA Environmental, Inc. (Pigniolo et al. 1997) as a result of the inventory and evaluation of cultural resources that may be affected by the Proposed Action. These mitigation measures have not been incorporated in the Project by the Applicant, but may be incorporated, in whole or in part, into BLM's Record of Decision for the Proposed Action following completion of on-going consultation with the SHPO and ACHP pursuant to Section 106 of the National Historic Preservation Act, and on-going Government-to-Government consultation with the Quechan Tribe as required by President Clinton's directive of April 29, 1994:

The following measures are proposed to mitigate the physical disturbance within the Project mine and process area which will occur to the features of religious-symbolic significance within the Indian Pass-Running Man ATCC:

• 4.1.6-4: Extant cultural features in the Indian Pass-Running Man ATCC should be avoided to the extent possible. KEA's GPS data base should be provided to Glamis Imperial to determine whether additional features can be avoided.
• 4.1.6-5: A professional archaeologist should flag or fence avoided features near construction areas prior to initial site preparation. Environmental inspectors should monitor avoidance. Flags outside of the perimeter fence should be removed immediately after construction of that fence.
• 4.1.6-6: An archaeological data recovery program conforming to that recommended in Chapter 9 of the KEA report should be implemented and should include a description and analysis of the features and artifacts that would be destroyed by the project and a technical archaeological report.

The following measures are proposed to mitigate the physical disturbance within the Project mine and process area which will occur to significant Native American trails and will cut-off the ability of the Quechan to travel physically and spiritually along the Trail of Dreams:

• 4.1.6-7: In consultation with the Quechan, extant trails in the Indian Pass-Running Man ATCC should be field mapped and their significance to Native Americans ascertained. Low-level aerial photography and video photography should be used to document trails that will be destroyed. It appears from present information that certain trail corridors through the Indian Pass-Running Man ATCC west of the mine and process area can be preserved, including routes to Avikwaame. Preserved segments with high Native American sensitivity should be nominated to the NRHP and a preservation plan prepared and adopted by the BLM.

The following measures are proposed to mitigate the physical disturbance and visual and aural intrusions in and from the Project mine and process area into the Indian Pass-Running Man ATCC which will conflict with the Quechan traditional practices and inhibit the Quechan's ability to conduct traditional religious activities at the Indian Pass-Running Man ATCC:

• 4.1.6-8: In accordance with the current Plan of Operations, the height of the waste rock stockpiles and heap should be restricted to 300 feet.
• 4.1.6-9: The BLM should continue consultation with the Quechan to ensure continued access to the Indian Pass-Running Man ATCC during Project implementation and after Project closure.

The following measures are proposed to mitigate the disturbance created within the Project mine and process area which will inhibit or destroy the Quechan's ability to use the Indian Pass-Running Man ATCC for traditional cultural education programs:

• 4.1.6-10: Provide for a cultural educational program which would include a professional-quality video documentary of the Indian Pass-Running Man ATCC prior to disturbance; a full or part-time teaching/curatorial position for a Quechan tribal member for a period of three (3) to five (5) years; preconstruction cultural educational classes in the Indian Pass-Running Man ATCC; and a comprehensive report documenting Quechan history and prehistory written in part or in its entirety by the Quechan.
• 4.1.6-11: Delay or phase construction activities to allow the Quechan the opportunity to conduct traditional cultural education in the Indian Pass-Running Man ATCC prior to their loss of this resource.
• 4.1.6-12: A non-technical report should be written based on the archaeological and ethnographic studies written for the Quechan tribe, addressing the part of Quechan history that would be destroyed by the mine.
• 4.1.6-13: Provide for the expansion plan for the Quechan Museum and curation of artifacts from the Project in this facility.

The following measures are proposed to mitigate the cumulative adverse effects that the disturbance created by the Project mine and process area will have on traditional cultural sites in Quechan territory:

• 4.1.6-14: The Indian Pass-Running Man ATCC, the Trail of Dreams, Pilot Knob, Muggins Peak, and the Picacho Basin should be nominated to the NRHP as traditional cultural properties.
• 4.1.6-15: A recording and protection program for the concentration of scratched petroglyphs at Indian Pass should be implemented.
• 4.1.6-16: Consultation should be initiated with the Quechan to identify a site of traditional concern that could be acquired and protected.

In addition to the measures listed above to mitigate the adverse effects on the Indian Pass-Running Man ATCC, the following measures are proposed to mitigate the physical disturbance created by the Project mine and process area to all or parts of seven (7) multicomponent and twelve (12) trail sites, which will result in data loss and the destruction of historic context:

• 4.1.6-17: An archaeological data recovery program (in accordance with the recommendations provided in Chapter 9 of KEA's cultural resource report) should be implemented at sites that cannot be avoided.

The measures listed above to mitigate the adverse effects on the Indian Pass-Running Man ATCC within the Project mine and process area will also mitigate the physical disturbance and out-of-character visual and aural intrusions to the Indian Pass-Running Man ATCC created by the construction of facilities within the Project ancillary area. In addition, the following measures are proposed to mitigate the physical disturbance to significant archaeological sites created by construction within the Project ancillary area.

• 4.1.6-18: No ground disturbance should be allowed within features that contribute to the significance of the Indian Pass-Running Man ATCC. In site CA-IMP-2727, the water pipeline should be rerouted to the area already disturbed by Indian Pass Road. Alternatively, boring could be utilized to avoid impacts to contributing features. All NRHP-eligible archaeological sites outside of the Indian Pass-Running Man ATCC should be avoided. Flagging and monitoring should be done in accordance with mitigation measure 4.1.6-5.

The following measures are proposed to mitigate the disturbance which could occur to features that contribute to the NRHP-eligibility of Camp Pilot Knob.

• 4.1.6-19: Prior to construction, a professional historical archaeologist should flag all features in the vicinity of existing poles that contribute to the NRHP eligibility of Camp Pilot Knob. Periodic archaeological monitoring should be conducted to ensure avoidance. In case of accidental damage, BLM should consult with SHPO regarding an appropriate mitigation program. Oral history and archival research should be considered along with archaeological data recovery in case of such an eventuality.
• 4.1.6-20: If adverse effects cannot be avoided, an interpretive display should be developed to supplement the E Clampus Vitus sign that already exists on-site. This display should address the relationship of Camp Pilot Knob to the overall Desert Training Center operations and include historical photos of the camp during its period of significance.

The following measure is proposed to mitigate the disturbance which could occur to significant archaeological sites during the construction of the overbuilt 92 kV/34.5 kV transmission lines.

• 4.1.6-21: All NRHP-eligible sites should be flagged for avoidance of direct impacts prior to construction of the transmission line. Avoidance of flagged archaeological sites should be part of the overall environmental monitoring program for the Project. In addition, periodic monitoring by a professional archaeologist and Quechan representative should be conducted to ensure avoidance. In case of accidental damage, BLM should consult with SHPO regarding an appropriate mitigation program. Oral history archival research, and ethnographic research should be considered as appropriate along with archaeological data recovery in case of such an eventuality.

4.1.6.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Indian Pass-Running Man ATCC, including the Trail of Dreams; seven (7) multi-component archaeological sites; and twelve (12) prehistoric trail sites in the Project mine and process area, each of which have been evaluated as eligible for the NRHP under Criteria "A," "C" and/or "D, " would not be avoided under the Proposed Action. If SHPO and the ACHP concur in the NRHP evaluation, adverse affects to each of these cultural resources would occur, and the impact of the Proposed Action would be considered significant and unavoidable, even after implementation of the mitigation measures specified in this EIS/EIR.

4.1.7. Visual Resources

4.1.7.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Have a substantial, demonstrable negative aesthetic effect.
• Substantially interfere with activities intolerant of bright lighting.

4.1.7.2. Impacts of the Proposed Action

In addition to other changes, this section has been substantially modified from the November 1996 Draft EIR in response to comments to: better analyze the visual impacts of the Proposed Action, including an additional KOP, and analyze the Proposed Action in light of the revised regrading/reclamation procedures.

Impacts to visual resources from the Proposed Action would result from: lighting of mine and process areas so that mining can occur during nighttime hours; visibility reduction resulting from the emission of particulate matter; and visual contrasts created by changes in line and form from the creation of new structures and facilities (such as the transmission line), altered surface colors, textures and vegetation cover (through surface disturbance) and changes in topography (waste rock stockpile, heap, and open pit landforms).

Lighting:

Project lighting used during nighttime operations at the administrative offices, shop area, lime silo, heap leach processing facility; portable light plants used at the active pits, waste rock stockpiles and heap leach; and head lights from mobile vehicles would produce "sky glow" and/or direct light which would be visible to some viewers, such as campers, hikers, and other nighttime dispersed recreation users in the vicinity of the Project mine and process area, including the adjacent wilderness areas, but should not be visible to developed recreation areas, such as Glamis or Gold Rock Ranch, because of distance and blocked line-of-sight. The Proposed Action includes restricting exterior night lighting to the minimum necessary, consistent with safety requirements and 24-hour-per-day operations. These effects of night lighting would not be significant.

The USMC has established a flight corridor (VFR-299) which occupies air space directly above the Project area. The Project area is currently used by the USMC for military overflights and for nighttime military operations using Night Vision Devices (NVDs). These devices can detect light at levels much lower than those that are detectable by the unaided human eye and, as such, Project lighting could pose a significant hazard to pilots during use of the NVDs, especially if the lighting is directed upward or is unexpected. Although the Proposed Action represents only a small portion of the available flight corridor, there would also be a small potential for significant interference with overflight operations from Project lighting during nighttime.

Visibility Reduction

The Proposed Action is a source of particulate matter (principally fugitive dust generated by travel on unpaved roads, blasting of rock in the pit(s), loading and unloading of ore and waste rock, combustion of diesel fuels in large engines, and wind erosion of exposed surfaces) and oxides of nitrogen (almost exclusively from the combustion of diesel fuels in large engines), both of which can contribute to the reduction in overall visibility (visual distance) in certain circumstances. In addition, particulate matter emitted in some circumstances can result in a visible "plume." No quantitative assessment of possible visibility (visual distance) reductions from the Proposed Action have been undertaken. However, computer modeling of the ambient concentrations of particulate matter and nitrogen oxides (see Section 4.1.4.2) indicate that the Proposed Action would comply with the applicable ambient air quality standards, and that ambient concentrations of these pollutants would be very low only short distances from the Project mine and process boundary. Experience at other mines in the region indicates that although there would be some circumstances where "plumes" (from blasting, or from diesel engine exhaust in certain circumstances) may be locally visible for short periods of time, substantial visibility reduction is not occurring as a result of project activities. The Proposed Action contains measures (such as dust control on unpaved roads) which substantially reduce the emissions of particulate matter and the resulting potential for visibility reduction. These impacts are judged to be below the threshold of significance.

Visual Contrast

The heap, waste rock stockpiles, and open pits constructed as part of the Proposed Action would represent a substantial visual contrast for viewers of the Project during the life of Project activities. The South Waste Rock Stockpile and the heap would both be constructed to a maximum height of 300 feet above existing grade, and would, therefore, be approximately 100 to 150 feet higher than any existing landform immediately adjacent to the Project mine and process area. The East Pit would remain open under the Proposed Action. The new transmission line and water wells in the Project ancillary area would also present a visual contrast, although to a much smaller degree. Following the completion of construction, the overbuilt 92 kV/34.5 kV transmission line would present little contrast over the existing 34.5 kV transmission line.

Implementation of the Reclamation Plan would reduce some of the impacts associated with the surface disturbance and new landforms associated with the Proposed Action over the long term. Following completion of Project operations, all structures constructed within the Project area as part of the Proposed Action (buildings, water wells, haul and maintenance roads, 92 kV/13.2 kV transmission line and substation, etc.) would be removed and the disturbed areas recontoured as necessary and seeded. The waste rock stockpiles and the heap would be recontoured, seeded, and would ultimately resemble smooth, rounded mounds. This would minimize the contrast of color and lines that would result from the Proposed Action post-mining but pre-final reclamation. However, the open pit, waste rock stockpiles and heap would remain as a permanent, substantial change to the line and form of the area.

The West Pit and Singer Pit would each be entirely backfilled under the Proposed Action. Some subsequent backfill may be necessary to raise the floor of the East Pit to a level higher than the level of any pit lake which may be eventually predicted to form from the inflow of ground water. All disturbed areas except the pit slopes would be regraded and revegetated, when no longer required for mine operations. This reclamation would create undulating land forms that are stable, do not allow for any pooling or ponding of water, and blend in with the surrounding undisturbed topography. Sharp edges would be rounded and straight lines altered to provide contours which are visually and functionally compatible with the surrounding terrain. The regrading would entail the construction of small "catchment" basins to collect precipitation and, thus, facilitate the revegetation of the disturbed areas. Other areas disturbed by facilities and roads, and the areas adjacent to diversions, would be fine graded to enhance moisture retention for reclamation and revegetation.

Revegetation activities in the disturbed areas immediately adjacent to the diversion channels and washes would include redistribution of soil, direct transplantation of trees and shrubs, seeding, monitoring and reporting. In all other areas, revegetation would include salvaging and stockpiling available soil, contouring and shaping accessible disturbed areas, reapplying soil materials as necessary, preparing seedbeds, seeding and transplanting, optimizing seed mixtures and rates, and monitoring and reporting.

Rough grading would be utilized to blend the top edges and crests of waste rock stockpiles and the heap and to construct the permanent diversion channels. Final grading would be utilized to construct small catchment basins for the collection and concentration of precipitation for revegetation of the waste rock stockpiles and leach pads. The waste rock stockpiles would have surfaces of mixed rock substrates and coarse alluvium with little developed soil or highly weathered material. The top surfaces of waste rock stockpiles would be rounded and contoured to form undulating land forms to blend with the surrounding terrain. Side slopes of waste rock stockpiles would be rough graded and small catchment basins installed. The configured surfaces and catchment basins would then be sown with seed or spread with stockpiled soil. During final reclamation, the small catchment basins (in which the plants can become established) would be constructed at varying intervals. In addition, scattered vegetation would naturally become established within a short time depending on local climatic conditions (rainfall events), softening the visual contrast with surrounding areas.

Although the Project facilities would be clearly visible from Indian Pass Road and other routes of travel in the immediate vicinity of the Project mine and process area, Project facilities in the Project mine and process area would not be easily viewable to most passersby from common viewing points in the surrounding, more distant, areas. There would be a limited view of the Project area from KOP #1, located on Ogilby Road (see Figure 4.2), the major access road in the vicinity of the Project area. The Project area would also be visible from KOP #2, located at the southern end of the top of Black Mountain (see Figure 4.4); from KOP #3, located on the top of a hill within the Picacho Peak Wilderness Area (see Figure 4.6); from KOP #4, an informal overnight camping area located along Indian Pass Road (see Figure 4.8). The Project area would also be visible from other elevated areas in the adjacent mountains, although the potential number of viewers from any of these locations would be very limited in number.

In accordance with BLM Visual Manual Section 8400, analyses of the visual effects of the Proposed Action following completion of Project mining and reclamation activities have been conducted. Photosimulations were prepared to simulate the post-mining, post-reclamation view from each of the same four (4) KOPs. These photosimulations were prepared on digitized versions of the views shown in Figure 4.2, Figure 4.4, Figure 4.6, and Figure 4.8. To ensure proper location and scaling of the landforms which make up the Proposed Action within the Project mine and process area, USGS digital elevation maps (DEMs) were combined into a single base map on which was electronically placed the Project mine and process area boundary and the final contours for each of the major Project landforms (waste rock stockpiles, heap, and open pit) (see Figure 2.4). This information was used to create computer-generated, three-dimensional views of the topography of the Project mine and process area following the completion of final reclamation from each of the four (4) KOPs. The computer-generated images were scaled and printed to match each of the views shown in Figure 4.2, Figure 4.4, Figure 4.6, and Figure 4.8, then used to check final form and placement of the simulated views so that they were created as accurately as possible. Using images of similar reclaimed areas in similar rock types from the Picacho Mine and the Mesquite Mine to match colors and textures, photosimulations were created for each KOP.

Figure 4.3 shows the view of the Project features after the completion of reclamation from KOP #1, on Ogilby Road. From this viewpoint, only the uppermost portions of the southern end of the South Waste Rock Stockpile and the heap would be visible, at a distance of approximately four (4) miles, over the slightly elevated terrain in the immediate foreground. These Project landforms would be viewed against the darker forms of Black Mountain and the Chocolate Mountains on the horizon.

The photosimulated view of the Project area after the completion of reclamation from KOP #2, the top of Black Mountain, and from KOP #3, the top of the hill immediately south of Indian Pass in the Picacho Peak Wilderness Area, are presented in Figure 4.5 and Figure 4.7, respectively. The view from these viewpoints looks down on the Project mine and process area from distances of five (5) miles and two (2) miles, respectively. From KOP #2, there is an unobstructed view of the waste rock stockpiles and the top of the heap. From KOP #3, all of the principal Project facilities are completely visible except the East Pit, which is partially hidden by the East Waste Rock Stockpile.

The photosimulation of the view toward the Project mine and process area after the completion of reclamation from KOP #4, the informal overnight camping area adjacent to Indian Pass Road, is presented in Figure 4.9. From this viewpoint, only the uppermost portions of the southern end of the South Waste Rock Stockpile and the heap would be visible, at a distance of approximately two (2) miles, over the slightly elevated terrain in the immediate foreground. These Project landforms would be viewed against the sky, with the darker forms of Black Mountain and Picacho Peak flanking the view.

To simulate views of the Project area following the completion of mining but prior to the completion of reclamation, additional photosimulations were constructed from each of these same four (4) KOPs. Post-mining, pre-final reclamation photosimulations of the view of the Project area are presented in Figure 4.10 from KOP #1, from KOP #2 in Figure 4.11, from KOP #3 in Figure 4.12, and from KOP #4 in Figure 4.13. Each of these views differ from the post-final reclamation views principally by the "stepped" slopes and flat tops of the waste rock stockpiles and the heap, and the reduced level of revegetation. Consistent with BLM Visual Manual Section 8400, since these photosimulations show the visual effects at an interim stage and not following the completion of the Proposed Action, they have not be used in the analysis of the long-term impacts of the Proposed Action.

The level of impact to visual resources would depend upon the number of viewers of the project, the viewers= observation point, and the duration of the disturbance from the Proposed Action. Visual effects of the Proposed Action were analyzed using the standard procedures presented in Section 8400 of the BLM Manual. The potential number of daily viewers from KOP #1 (Ogilby Road) may number up to 1,000 (see 3.15). The potential number of viewers from KOP #2 would be small, averaging only a few per day, while the number of viewers from KOP #3 is likely to be very small, less than a few per month. The potential number of viewers from KOP #4 would vary depending on the season; during the winter months the number may reach several hundred per month, whereas in the summer months the number may be only a few per week.

The line of the reclaimed Project features within the Project mine and process area would approach undulating, but would remain somewhat discontinuous and have some areas with an angular line. The color of the reclaimed Project features would approach tan to brown, and would generally be lighter than much of the surrounding surface rock, which is coated with a desert varnish. The form would be rounded and rhomboid in the near ground and conical in the middle ground. The texture would approach a middle patchy. The Proposed Action would result in the permanent placement of certain line and form features in an area of the landscape that did not otherwise have those line and form features, and the overall color, line, form, and texture of the post-reclamation Project mine and process area features would not be reasonably consistent with the surrounding area. Accordingly, the post-reclamation visual impacts of the Proposed Action are determined to be above the level of significance.

Conformance with Class II Visual Objectives

Landforms constructed under the Proposed Action would contrast visually with the surrounding land even after completion of final reclamation. The Project area is located in an area of the California Desert Conservation Area (CDCA) designated Class L (Limited Use). Class L areas are generally managed to conform to the BLM Class II visual objectives (see Section 3.7.1). Based upon the visual effects of the Proposed Action described above and the BLM Class II visual objectives (i.e., to retain the existing character of the landscape) which have generally been applied to this area, the Proposed Action does not conform to the visual objectives. This lack of conformance is a significant impact.

4.1.7.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.7-1: Following completion of Project mining activities, all buildings, equipment, supplies, and debris shall be removed to improve the visual appearance of the Project area.
• 4.1.7-2: Dust suppressants shall be utilized, as necessary and in accordance with ICAPCD permit requirements, on haul roads to minimize fugitive airborne dust generation on the Project mine and process area.
• 4.1.7-3: In conformance with the Reclamation Plan as approved by the BLM and Imperial County, all disturbed areas shall be recontoured and reseeded or revegetated with native or indigenous species complementary to vegetation found in the surrounding area.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

No specific measures.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

• 4.1.7-4: High intensity lighting used for mining and processing operations at night shall be directed downward to reduce fugitive light. Lighting shall have reflectors or shields to further minimize fugitive light. Light stanchions shall be no higher than necessary for safe and efficient lighting.
• 4.1.7-5: Applicant shall establish a working relationship with the U.S. Marine Corps (USMC) to ensure that nighttime lighting of the Project mine and process area does not substantially interfere with the use of Night Vision Devices (NVD) in the vicinity of the Project area or nighttime overflight operations within flight corridor VFR-299. As part of this mitigation measure, Applicant shall provide the USMC Air Station, Yuma, Arizona, with a detailed, to-scale, map of the Project area identifying the principal surface facilities, transmission lines, and locations of potential light sources to enable the USMC to avoid or accommodate these areas during nighttime flight activities.

4.1.7.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in unavoidable physical changes in the existing contour and character of the Project area. These changes would be visibly most apparent over the active life of the Project, but would diminish through the completion of reclamation and revegetation activities contained as part of the Proposed Action. These physical changes to the area would be permanent, but would continue to lessen following the completion of final reclamation as natural processes continued to soften the line and form to and match the surrounding landscape. These residual impacts to the visual character of the Project area are judged to be significant and unmitigatable.

The Proposed Action would result in a visual contrast with the surrounding area and would change the existing character of the landscape to a degree which would not conform with the BLM Class II visual objectives which have been applied to this Class L-designated area. This lack of conformance is a significant, unmitigatable impact.

4.1.8. Noise

4.1.8.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Would have the potential to result in a significant increase in noise levels to sensitive receptors in the area; or
• Conflict with any applicable noise restrictions imposed by regulatory agencies.

4.1.8.2. Impacts of the Proposed Action

The Proposed Action would not conflict with any applicable noise restrictions imposed by regulatory agencies.

The noise generated by the proposed mining operations would be typical of most construction and mining projects, and could be intense for short intervals. Ore loading and handling, and other mining processes, can generate noise levels up to 95 dB(A) at 25 feet, although typical average noise levels generated by Project operations (which continue 24 hours per day, seven (7) days per week) could be substantially lower. Safety backup alarms on haul truck and other major equipment may generate 100 dBA at 25 feet, and blasting (which the Proposed Action restricts to daylight hours) can cause very short-duration noise levels in excess of 140 dBA at 25 feet.

Noise is attenuated by distance, atmospheric conditions, and topography. Sound wave divergence typically results in a six (6) dBA decrease for every doubling of distance from a noise source (ICPBD 1978). This assumption is conservative since it does not account for noise attenuating factors such as topography, wind, temperature gradients, atmospheric pressure, and other site-specific factors, such as the upward deflection of noise generated down in the bottom of a pit. Assuming a typical peak noise levels from the day-to-day Project activities within the Project mine and process area of 95 dBA, and assuming a typical noise source location near a point of public access (the center of the South Waste Rock Stockpile, approximately 1,600 feet from Indian Pass Road), then the peak ambient background noise at the nearest point of public access would be approximately 60 dBA. Peak ambient background noise levels (50 dBA to 30 dBA) would be expected to be approached at a distance of approximately one-half (2) to five (5) miles, respectively, from the Project mine and process area from these activities. Typical average noise levels generated by Project operations would be expected to be substantially lower. Substantially higher level noise values would be expected during the instant when blasting occurs.

There are no permanent noise-sensitive receptors (i.e., residences, schools, hospitals, etc.) located in the vicinity of the Project area. The nearest permanent noise-sensitive receptors are located at the Gold Rock Ranch, approximately seven (7) miles southwest of the Project mine and process area. Based upon the projected attenuation of noise with distance, sound pressure levels generated from all normal operating activities at the Project mine and process area should not be audible at this receptor. However, the short term, higher level, noise values generated by blasting may be audible and distinguished from natural noise sources, but would be similar to those generated from the existing military overflights. While some Project-generated noise levels may be discernable, the projected noise levels would not be intrusional and noise impacts would be below levels of significance.

Temporary or transient noise receptors, such as dispersed recreational uses in the area around the Project mine and process area, including portions of the Indian Pass Wilderness Area and the Picacho Peak Wilderness Area, would be exposed to audible noises generating by Project activities, depending on their distance from the Project mine and process area, their location, local conditions, and the specific activities being undertaken by the Project. While some Project-generated noise levels may be barely discernable, other noises and noise levels would likely be judged intrusional, and some of these receptors may decide to avoid the areas surrounding the Project mine and process area, and instead use other recreational areas, during the life of the Project, especially during weekends of heavy recreational use. The effects of Project noise alone on dispersed recreational users are judged significant because of blasting on weekends of heavy recreational use; however, see Section 4.1.9.2 for the assessment of all Project effects on recreational use.

The effects of project generated noise on wildlife is discussed in further detail in Section 4.1.5.3.

4.1.8.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.8-1: All heavy equipment, drilling rigs, and other internal combustion engines shall be equipped with mufflers to minimize noise generated during construction, operation and reclamation activities.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.8-2: Applicable Occupational Safety and Health Administration (OSHA) worker noise protection requirements, as set forth in 29 CFR 1910.95, et seq, and California Occupational Safety and Health Administration (Cal-OSHA ) requirements, as set forth in 8 CCR 5095, et seq, shall be implemented by the Applicant.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

• 4.1.8-3: Blasting shall only be conducted during daylight hours unless required for safety reasons. During the months of October through March, the Applicant shall take all reasonable steps to avoid blasting on weekend days (Saturday and Sunday), and shall not blast on the following major recreational holidays (Thanksgiving [Thursday through Sunday]; Christmas [Christmas day and all associated weekend days]; New Years [New Years eve, New Years day, and all associated weekend days]; and President's Day [and associated weekend days]) unless required for safety reasons or necessary to maintain production due to the mechanical breakdown of production equipment or other unforseen circumstances. Prior to conducting blasting on any of these designated weekend days or major holidays, Applicant shall on that day notify the BLM and take reasonable steps to notify those recreational users of the public lands located along Indian Pass Road or within one (1) mile of the boundary of the Project mine and process area boundary of the approximate time that blasting will occur.

4.1.8.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in unavoidable increases in ambient noise levels within a conservatively estimated five-mile radius of the Project mine and process area over the life of the Project. Noise levels would diminish with distance from Project noise sources, and ambient noise would decrease with time as the pit walls, heap, and waste rock stockpiles provide increasing topographic attenuation of sound levels from noise sources within the Project mine and process area.

Based on the absence of sensitive noise receptors in the vicinity of the Project area, the effects of noise from the Proposed Action would be below the level of significance.

4.1.9. Land Use

4.1.9.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

This land use impact assessment evaluates the potential effects of the Proposed Action on existing and planned land uses in the vicinity of the Project area. It also evaluates the effects of the Proposed Action on wilderness and recreational resources in the Project area and vicinity. The Proposed Action would normally have a significant effect on the environment if it would:

• Conflict with adopted environmental plans and goals of the community where it is located;
• Disrupt or divide the physical arrangement of an established community;
• Conflict with established recreational, educational, religious or scientific uses of the area;
• Result in nonconformance with the Wilderness Act of 1964 or the BLM Interim Wilderness Management Policy;
• Substantially degrade or reduce the quantity or quality of the area available for existing or future recreational opportunities; or
• Result in the unmitigated loss of a unique recreational resource.

The effects of the Proposed Action would also be significant if the Project was incompatible with existing land uses in the vicinity, or if the effects of the Proposed Action would not be in conformance with the applicable land use plans and policies described in Section 3.9.1.

4.1.9.2. Impacts of the Proposed Action

In addition to other changes, this section has been modified from the November 1996 Draft EIR in response to comments to: provide additional information regarding the impacts of the Proposed Action on recreational uses in the area, including recreational use of the wilderness areas.

Compatibility with Existing Land Uses:

The Project area is undeveloped and the area surrounding the Project area is occupied by large expanses of public land administered by the BLM. The area is relatively isolated and remote from concentrated land uses. The area is generally regarded as open space, providing desert habitat for wildlife and dispersed recreational opportunities. The principal land uses in the vicinity of the Project area include: dispersed recreation (hunting, camping, rock collecting, etc.); military aircraft overflight training; and commercial mineral exploration. Two (2) wilderness areas (Indian Pass Wilderness Area and Picacho Peak Wilderness Area) are located approximately one and one-half (12) miles north and one-half (2) mile northeast, respectively, of the Project mine and process area at their closest points; compatibility of these wilderness areas with the Proposed Action is discussed in the subsection entitled "Wilderness Areas," below. Indian Pass ACEC is located approximately three-quarters (3/4) of a mile north of the Project mine and process area; compatibility of the cultural resource values for which the Indian Pass ACEC was established is discussed in Section 4.1.6.2. The impact of the Proposed Action on dispersed recreation within the area is discussed in the subsection titled "Recreational Resources," below. There are no current plans to include the Project area in any park system.

Three (3) precious metal mines (American Girl/Oro Cruz Mine, Mesquite Mine, and Picacho Mine) are located within ten (10) miles the Project mine and process area; the Proposed Action would have no impact on these existing mines. The nearest residence and area of concentrated public activity is the Gold Rock Ranch, located approximately seven (7) miles southwest of the Project mine and process area. The Proposed Action is compatible with this existing use, since the Project would result in negligible increases in noise and traffic along Ogilby Road, and would result in negligible decreases in air quality, for the residents and visitors at Gold Rock Ranch. No other residences exist within ten (10) miles of the Project mine and process area.

The new transmission lines could pose a potential physical hazard to low-flying military aircraft, especially during nighttime exercises when pilots are training with night vision devices (NVD) which substantially amplify the available light; the Proposed Action includes the installation of special devices which are visible only at night with the use of NVD (see Section 2.1.9.3.1). Project night lighting could present a similar hazard to the use of NVD; a mitigation measure to reduce the impact of this lighting to below the level of significance is provided in Section 4.1.7.3. However, Project blasting during mining operations could be a significant potential hazard to low-flying military aircraft using the general area for training exercises.

Expanded discussions of the potential effects of the Project on surrounding area are provided in the other sections of this Chapter 4 of the EIS/EIR.

Compatibility with Adopted Land Use Plans and Policies:

In passing the Federal Land Policy and Management Act of 1976 (FLPMA), "... Congress declared that the policy of the United States would be to manage public lands to protect the quality of various natural resources, outdoor recreation and human occupancy and uses." (Section 102(a)(8)) The policy statement went on to include "... (12) the public lands [shall] be managed in a manner which recognizes the Nation's need for domestic sources of minerals, food, timber, and fiber from the public lands including implementation of the Mining and Mineral Policy Act of 1970 ... as it pertains to the public lands; ...." [Section 102(a)(12)].

FLPMA defines multiple use as "... management of the public lands and their various resource values so that they are utilized in the combination that would best meet the present and future needs of the American people; making the most judicious use of the land for some or all of these resources or related services over areas large enough to provide sufficient latitude for periodic adjustments in use to conform to changing needs and condition; ...." The definition goes on to allow some areas to be managed for less than all the resources. "... a combination or balanced and diverse resource uses that takes into account the long-term needs of future generations for renewable and nonrenewable resources, including, but not limited to, recreation, range, timber, minerals, watershed, wildlife and fish, and natural scenic, scientific and historical values ..." is also a part of a multiple use. [Section 103 ©].

Primary or major uses are defined as those which A... includes and is limited to domestic livestock grazing, fish and wildlife development and utilization, mineral exploration and production, rights-of-way, outdoor recreation, and timber production. [FLPMA Section 103(1)].

The California Desert Conservation Area (CDCA) Plan is a multiple use, sustained yield plan developed to manage various resources including mineral development [FLPMA Section 601(d)]. The Proposed Action is consistent with the CDCA Plan. Therefore, it is consistent with Section 601(a)(4) and Section 601(b) of FLPMA. In addition, Section 601(f) of FLPMA did not amend the 1872 Mining Law to preclude mineral development or production within the CDCA. The development of locatable minerals on mining claims in areas designated by the BLM as Class L is authorized subject to applicable federal regulations (43 CFR 3809) and state and local laws.

The overbuilding of the existing 34.5 kV transmission line is in conformance with the respective goals and objectives set forth in both the Land Use Element and the Conservation and Open Space Element to the General Plan. The County has also zoned the entire area of the Proposed Action as S-Open Space, which permits multiple uses consistent with the Conservation and Open Space Element and the General Plan.

The proposed Project is in conformance with the Southern California Association of Governments (SCAG) Regional Comprehensive Plan and Guide (RCPG) (SCAG 1997).

Wilderness Areas:

The northern boundary of the Project mine and process area is located approximately one-half (2) mile southwest of Picacho Peak Wilderness Area, and approximately one and one-half (12) miles south of Indian Pass Wilderness Area. The Proposed Action would not result in any surface disturbance within, or other direct impacts to, either wilderness area. However, major facilities within the Project mine and process area would be visible from some elevated areas within both Indian Pass Wilderness Area and Picacho Peak Wilderness Area (see Section 4.1.7). Minor increases in annual ambient levels of particulate matter would result in the wilderness areas from Project emissions (see Section 4.1.4). Blasting and other noises generated by Project operations within the Project mine and process area would be audible within those portions of the wilderness areas nearest the Project mine and process area (see Section 4.1.8.2). Indian Pass Road, the primary access to these wilderness areas from the west, would be realigned around the Project mine and process area over the life of the Project, and would be returned to approximately its original location after the completion of mining activities. However, the road would be kept open and would not restrict travel to the wilderness areas.

Section 103(d) of the California Desert Protection Act of 1994, which created both Indian Pass Wilderness Area and Picacho Peak Wilderness Area, reads:

"No Buffer Zones.--The Congress does not intend for the designation of wilderness areas in section 102 of this title to lead to the creation of the protective perimeters or buffer zones around any such wilderness area. The fact that nonwilderness activities or uses can be seen or heard from areas within a wilderness area shall not, of itself, preclude such activities or uses up to the boundary of the wilderness area."

Accordingly, only the direct effects of the Proposed Action on these wilderness areas can be assessed for their effects on wilderness values themselves; the indirect effects of the Proposed Action on these wilderness areas must be evaluated without reference to the areas= wilderness characteristics and values. Based upon the lack of direct impacts to these wilderness areas from the Proposed Action, the impacts to wilderness areas from the Proposed Action are below the level of significance.

Recreational Resources:

The entire Project mine and process area (approximately 1,571 acres) would be fenced and closed to the public during the entire operating life of the Project, which would eliminate these lands from any recreational use during this period. Following the completion of mining operations, surface facilities (buildings, roads, process facilities and ponds, etc.) and foundations would be removed, and final reclamation activities (grading and rounding of waste rock stockpiles and the heap, revegetation, installation of guzzlers, etc.) commenced. With the completion of final reclamation, the perimeter fence would be removed and public access to the area reestablished, except for the 198-acre area of the open East Pit, which would be surrounded by a rock boulder barrier to prevent vehicle access and discourage pedestrian access. As discussed in Section 4.1.5, both vegetation and wildlife habitat values would slowly recover, and opportunities for hunting, hiking, camping and other dispersed recreational activities would again be available in the Project mine and process area (with the exception of the 198-acre open East Pit).

Construction and operation of Project facilities within the Project mine and process area would not prevent camping, hunting or other dispersed recreation activities in areas outside of the fenced boundary of the Project mine and process area. Most recreational activities in the immediate vicinity of the fenced Project mine and process area would, however, be affected by Project activities conducted during the projected 20-year life of the Project within the Project mine and process area. Dispersed recreation would be affected by emissions of air pollutants (see Section 4.1.4), visibility of the mine components (see Section 4.1.7), noise generated by mine operations (see Section 4.1.8.2), and Project-related traffic on Indian Pass Road (and possibly Ogilby Road) (see Section 4.1.11.1.2), even though mitigation measures to reduce the effects of these air emissions, visibility, noise, and traffic impacts are presented in the respective sections of the EIS/EIR. As a result of these effects of the project, dispersed recreational use of the areas adjacent to the Project mine and process area would likely be reduced during the life of the Project. Environmental education activities currently conducted in the vicinity of the Project mine and process area, specifically the viewing of cultural resources, would likely also be substantially reduced or displaced by the Project during the life of the project and after because some of the cultural resources would be inaccessible, while others would be permanently lost.

Recreational users of those portions of Picacho Peak Wilderness Area and Indian Pass Wilderness Area closest to the Project mine and process area would almost certainly hear noises generated by the Project and see the major features of the Project during the day (and lights from the Project mine and process area during the night). Although the noise and lights would last only through the estimated 20-year life of the Project, the daytime views of the (reclaimed) Project features (waste rock stockpiles, heap, and open pit) would be permanent. People who go into wilderness areas such as these usually go there because of the solitude and the lack of human-related distractions. Noise and lights, especially at night, from the Project mine and process area would likely reduce the use of these wilderness areas by people seeking this solitude. Other recreational users of the area may not be as adversely affected by the Project noise and lights as the wilderness users.

Project facilities constructed outside of the Project mine and process area, including the buried water pipeline, water wells, and the new transmission line, would not affect public access to the primitive campsites along the washes adjacent to Indian Pass Road in the Indian Pass recreational corridor, and Project operations would not encourage or overly restrict recreational traffic traveling on Indian Pass Road to or from the wilderness areas or other potential recreation areas located north of the Project mine and process area. However, vehicle campers along the Indian Pass recreation corridor adjacent to Indian Pass Road and the Project ancillary area would be most affected by Project-related noise, lights, and Project-related vehicle traffic along Indian Pass Road, as well as the loss of access to the microphyll woodland habitat located within the Project mine and process area. As a result, informal overnight camping in the Indian Pass recreation corridor would probably diminish during the projected 20-year life of the Project, especially for those people with two-wheel drive vehicles that cannot travel far from Indian Pass Road. Campers would also likely be displaced and disturbed by the noise and activities created during pre-mining construction activities associated with the new transmission line and ground water system. Following the completion of reclamation activities within the Project mine and process area, the new transmission line would be removed, the water wells would be abandoned in conformance with agency requirements, and the buried water pipeline would be abandoned in place. As a result, little residual effect on vehicle camping within the Indian Pass recreational corridor would be likely beyond the life of the Project.

There are no unique recreational resources within the Project area, and comparable recreational opportunities would still be available in large areas of public land similar to, but outside of, the Project area. There are no current plans for the Project area to be incorporated into either the state or federal park system. There are approximately 4.4 million acres of BLM Class L lands in the CDCA which are generally available for dispersed recreation. Given the availability, both nearby and in other areas of eastern Imperial County, of large areas with similar, although not identical, opportunities for dispersed recreation, the effects of the Project on recreation resources would be below the level of significance.

While not intended, the proximity of the Project mine and process area to Indian Pass Road could attract some visitors to the area as sightseers to observe the large mine equipment and active mining operations.

4.1.9.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.9-1: At the conclusion of mining activities, consistent with the approved Reclamation Plan, Applicant shall recontour all disturbed areas except the pit slopes as appropriate to create undulating land forms that are stable, safe, do not allow for any pooling or ponding, and blend with the surrounding undisturbed topography. Applicant shall also construct a loose rock barricade comprised of large boulders to prevent vehicle access and restrict public entry into the open pit area(s).

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.9-2: Applicant shall conduct mining operations in conformance with the Class L BLM multiple land use guidelines outlined in the CDCA Plan for mining in the area. The Applicant shall also comply with the federal land use requirements prescribed in 43 CFR 3809.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

• 4.1.9-3: Applicant shall keep the USMC air station in Yuma, Arizona apprized of the current schedule and location for blasting at Project mine and process area to minimize the potential for low-flying military aircraft to be over the Project mine and process area during blasting activities.

4.1.9.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in an unavoidable change to the existing land use in the Project mine and process area from open space to mining over the 20-year life of the Project. Following completion of mining and reclamation activities, the majority of the Project mine and process area would be available again as open space. However, public access to the 198-acre open East Pit area would be indefinitely restricted by a loose rock-rubble barricade.

The Proposed Action would reduce the area otherwise available for use by low-flying military aircraft, especially during nighttime exercises when pilots are training with night vision devices (NVD), during the life of the Project; mitigation measures are available to reduce this impact to a level which is less than significant, and this effect would be eliminated following the completion of final reclamation.

Areas in the immediate vicinity of the Project mine and process area, including some portions of the nearby wilderness areas, would be unavoidably affected by emissions of air pollutants and noise from the Proposed Action, and portions of the Proposed Action would be easily visible from immediately adjacent or elevated locations. Project-related traffic would also unavoidably affect users of the land in the immediate vicinity of the Project area. These effects would be less than significant on the nearby wilderness areas, and would also be less than significant on the dispersed recreational resources.

4.1.10. Socioeconomics

4.1.10.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Induce substantial growth or concentration of population;
• Displace a large number of people;
• Cause a substantial reduction in employment;
• Substantially reduce wage and salary earnings; or
• Cause a substantial net increase in County expenditures.

4.1.10.2. Impacts of the Proposed Action

A net beneficial socioeconomic effect is projected from the construction and operation of the Proposed Action.

The Proposed Action is expected to create jobs for 120 full-time employees, as many as 40 of which could be filled by the current employees of the Picacho Mine, which would be closing. Initial construction may require as many as 225 workers, although only a portion of these would be working on the Project at any single time. During the Project life, additional construction projects (such as the construction of an additional phase of the heap leach pad) may require up to 40 workers. Construction of the overbuilt 92 kV/34.5 kV transmission line would require up to 30 workers.

Indirect employment opportunities generated by the Proposed Action were estimated by applying multipliers commonly used in the mining industry. Dobra (1988) assumes that for every job created in the mining industry, an additional 1.25 job opportunities are created in other sectors of the economy. Using this factor, the Project is estimated to create, or continue in existence, 150 jobs. The majority of these jobs would be expected to be filled by current residents of Imperial County, California or Yuma County, Arizona, although there may be a very small increase in demand for housing and community services in these areas over the life of the Project if some of the jobs are filled by workers from outside these areas. Based exclusively on the distance required to drive from the Project mine and process area to Yuma (35 miles) versus Holtville (52 miles), Brawley (56 miles), and El Centro (65 miles), it is likely that more workers would eventually reside in Yuma, Arizona over locations in the Imperial County.

The following estimates of Project expenditures and estimated tax revenues from the Project were provided by Glamis Imperial (Personal Communication, C.K. McArthur, Chemgold, Inc., 1995; Personal Communication, Steve Baumann, Glamis Imperial, 1996).

• Project annual payroll, including benefits, is estimated to be approximately $7 million for 120 employees.
• Approximately $48 million in capital would be expended for the Project during 1998. Sales tax on these capital expenditures would amount to approximately $3.72 million. For each year thereafter, average annual capital expenditures would amount to approximately $1.7 million, generating approximately $0.13 million per year in sales tax for capital expenditures only.
• Annual non-capital expenditures are estimated to total $26 million (including payroll).
• Geographic distribution of annual non-capital expenditures have been estimated using data derived from the Picacho Mine operations. It is estimated that 37.1 percent ($9.65 million) of non-capital expenditures would be made in California and 38.1 percent ($9.9 million) would be made in Arizona, for an estimated total of 75.2 percent ($19.55 million) in local non-capital expenditures. The remaining 24.8 percent ($6.45 million) of non-capital expenditures would be made in areas outside of California and Arizona.
• Property taxes in Imperial County are assessed at approximately 1.1 percent per year of the total assessed value. Depending on the assessed valuation of the Project property, projected property taxes are estimated to range between $250,000 and $600,000 per year.

Based upon the information provided above, the Proposed Action would not induce substantial growth or concentration of population; displace a large number of people; cause a substantial reduction in employment; or substantially reduce wage and salary earnings, and thus the Proposed Action would not result in a significant adverse socioeconomic effect. Based on the analyses presented in Section 4.1.11.1.2 and Section 4.1.11.3.2, the Proposed Action would also not cause a substantial net increase in County expenditures, and would not be considered significant.

4.1.10.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

No mitigation measures are proposed or recommended.

4.1.10.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

There would be no unavoidable adverse socioeconomic effects from the Proposed Action. Beneficial socioeconomic effects would result from the Proposed Action in the form of employment opportunities, tax revenues and increased spending in the local region for goods and services by Project employees and contractors. The adverse socioeconomic effects of the Proposed Action would be below the level of significance.

4.1.11. Roads and Public Services

4.1.11.1. Road and Transportation System

4.1.11.1.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Cause an increase in traffic which is substantial in relation to the existing traffic load and capacity of the street system; or
• Prevent or substantially reduce public access through the elimination of important existing routes of travel.

4.1.11.1.2. Impacts of the Proposed Action

The Proposed Action would require the realignment of an approximate 6,000-foot section of Indian Pass Road around the western perimeter of the Project mine and process area to allow for excavation of the West Pit in the current road location. The relocated road would cross the adjacent "West Pit West" wash "at-grade" at two (2) locations; one (1) upstream and one (1) downstream of the Project mine and process area; to allow for the safe passage of traffic during mine operations.

The Proposed Action includes maintaining Indian Pass Road open to the public during construction of the relocated portion of the road; posting signs at the two (2) wash crossings along the relocated portion of Indian Pass Road warning drivers not to cross the wash when flooded; and undertaking emergency repairs or maintenance if Indian Pass Road is damaged by flooding where it crosses these washes.

Because "West Pit West" wash is subject to infrequent flooding, Indian Pass Road would be subject to temporary closure during the period that Indian Pass Road is realigned and this wash is flowing. An alignment of Indian Pass Road which does not cross the wash (that is, which is entirely on the east side of the wash) is the best location to minimize long-term maintenance costs and environmental effects. Accordingly, at the request of the ICPWD, the Proposed Action includes returning the realigned section of Indian Pass Road to a location within the Project mine and process area east of and approximately parallel to the diverted "West Pit West" diversion channel. This location would be on land previously disturbed by Project activities adjacent to the "West Pit West" diversion channel. Once Indian Pass Road had been realigned and the reclamation bond for this work released by the agencies, maintenance on Indian Pass Road reverts to Imperial County. The impacts to Indian Pass Road, and to the public's use of Indian Pass Road, from the road realignment and subsequent relocation would be below the level of significance.

The Proposed Action would also result in the realignment of the intersection of Indian Pass Road and Ogilby Road to change the acute angle of the intersection to a right angle. The section of Indian Pass Road which would be replaced would be reclaimed under the Proposed Action. The net effect to the road system of realigning the road intersection would be beneficial, and any adverse environmental effects resulting from realigning the intersection would be below the level of significance.

Fencing of the Project mine and process area boundary, and construction of the Project facilities within the Project mine and process area, would necessitate the closure of several unmaintained dirt "routes" identified on BLM Desert Access Guide 21 (Midway Well) which pass through the Project mine and process area (see Figure 2.8), at least until the Project perimeter fence is removed following the completion of final reclamation. However, as also shown on Figure 2.8, alternative open routes are available in the immediate vicinity of the Project mine and process area which would allow vehicles to travel from Indian Pass Road to Hyduke Road, and to drive around the Project mine and process area. Therefore, the closures of these routes, either temporarily or permanently, would not result in a significant effect.

The Proposed Action would result in an estimated 47 light-weight vehicle round-trips to the Project area daily, and an estimated average three and one-half (32) heavy-weight vehicle round-trips per day. This represents approximately a five (5) percent increase in the volume of traffic currently observed on Ogilby Road south of its crossing of the Southern Pacific railroad tracks and north of the exit off Interstate Highway 8. This estimate assumes that approximately 25 percent of the estimated 64 workers which would be scheduled to work on any given day voluntarily carpool to the Project area, which is consistent with the experience with other mines in the area. Traffic volume could be higher if fewer workers carpoolled, and would somewhat higher during the approximately six (6) month construction period as a result of the additional workers and truck traffic. Truck traffic on Ogilby Road associated with the Project would not substantially increase degradation of the roadbed, nor result in a substantial increase in maintenance costs for this road.

Although no traffic counts are available for either Ogilby Road in the vicinity of the Project, or for Indian Pass Road, traffic volume is believed very light on both roads. Project employees would work staggered shifts and different work periods. This would result in dispersed traffic flow to and from the Project area throughout the day. The Proposed Action also contains the realignment of the intersection of Ogilby Road and Indian Pass Road to a right angle. Thus, there is no reason to believe that the construction of either a right- or left-hand turn pocket on Ogilby Road is necessary. The effects of traffic associated with the Proposed Action would be below the level of significance.

Neither BLM Hyduke Road nor the open routes of travel were constructed for heavy vehicle use, and moderate to extensive upgrade of these roads would be required to permit heavy vehicle traffic. The Proposed Action states that none of these roads in the vicinity of the Project mine and process area would be used for heavy truck or equipment traffic.

Fencing of the Project mine and process area (and construction of the Project facilities) would close several BLM open routes of travel currently located within the Project mine and process area. In addition, the BLM would close those sections of these same BLM open routes of travel located outside the Project mine and process area which would be then end at the Project mine and process area fence. However, public vehicular access to all areas around the Project mine and process area is still available to the public on all sides of the Project mine and process area from BLM routes of travel, Indian Pass Road, and Hyduke Road, which would remain open (see Figure 2.8). During the life of the Project, Glamis Imperial would be responsible, under the direction of Imperial County, for the maintenance of Indian Pass Road from Ogilby Road to a point beyond the Project mine and process area. Any costs associated with possible increase in road repairs required as a result of increased Project-related traffic on County-maintained paved roads would be off-set by the additional property taxes and sales taxes provided to the County by the Project. Thus, the level of impacts to roads, and the impacts to public access in the vicinity of the Project, would be below the level of significance.

Construction of the water wells, water pipeline, and new transmission line in the Project ancillary area would require the construction of some new access roads and "spur" roads. Following the completion of final Project reclamation, Project facilities constructed within the Project ancillary area would be removed (or, in the case of the buried pipeline, buried in place), and these access and "spur" roads reclaimed. In addition, the haul and maintenance roads within the Project mine and process area to the open pit would be reclaimed. However, the contrast between the reclaimed roadbeds and the surrounding areas may encourage public use of these closed roads in areas where darkly "varnished" desert pavement was disturbed. This is considered to be an insignificant effect, although a measure is proposed to mitigate the impact further.

4.1.11.1.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.11.1-1: Applicant shall realign an approximate 6,000-foot section of Indian Pass Road around the Project mine and process area prior to surface disturbance which would impede through traffic on this road, and shall maintain Indian Pass Road open to the public during construction of the relocated portion.
• 4.1.11.1-2: Applicant shall not route heavy traffic over Hyduke Road.
• 4.1.11.1-3: That section of Indian Pass Road realigned prior to mine construction shall be realigned to a location east of and approximately parallel to the diverted West Pit West diversion channel as soon as practicable, but prior to the completion of final reclamation and release of the physical reclamation bond.
• 4.1.11.1-4: Applicant shall post warning signs at the two (2) wash crossings along the relocated portion of Indian Pass Road warning drivers not to cross the wash when flooded, and shall undertake repairs or maintenance, as may be necessary and authorized by Imperial County, if Indian Pass Road is damaged by flooding where it crosses these washes.
• 4.1.11.1-5: Applicant shall apply water and/or dust suppressants (chemical treatments acceptable to all appropriate agencies) to Indian Pass Road from its intersection with Ogilby Road to the boundary of the Project mine and process area.
• 4.1.11.1-6: Applicant shall acquire the necessary approvals of the BLM and Imperial County to construct the relocated section of Indian Pass Road and the realigned intersection of Indian Pass Road and Ogilby Road, and shall design, construct and maintain these facilities in accordance with the permit conditions which are applicable at the time of construction.
• 4.1.11.1-7: Applicant shall encourage employees and construction workers to carpool to the Project area.
• 4.1.11.1-8: Applicant shall maintain Indian Pass Road from the intersection with Ogilby Road to the point immediately northeast of the Project mine and process area, including the section of the road relocated by the Project, during the active life of the Project in consultation with the Imperial County Public Works Department.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

No specific measures.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

No mitigation measures are proposed.

Other Mitigation Measures (These are measures which may further reduce the impacts of certain effects which are below the level of significance without mitigation):

• 4.1.11.1-9: To reduce the potential that access and "spur" roads constructed to provide temporary access to the new transmission line, water pipeline, and water wells may continue to be used by the public following the completion of Project reclamation, these roads, when constructed in areas of dark "desert varnished" desert pavement, shall be reclaimed in a manner, such as the application of Permeon, to reduce the visual contrast between the disturbed area and the surrounding undisturbed dark desert pavement.

4.1.11.1.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in a slight, unavoidable, and less than significant increase in traffic on, and traffic-generated fugitive dust from, public roads in the vicinity of the Project area over the 20-year life of the Project. The Proposed Action would also result in the closure of several currently open "routes" in the immediate vicinity of the Project mine and process area, which would also not result in a significant effect. When mitigated, the effects of the Proposed Action on traffic and the local transportation system in the vicinity of the Project area would not exceed levels of significance.

4.1.11.2. Utilities

4.1.11.2.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Encourage activities requiring large amounts of fuel, water, or energy;
• Use fuel, water, or energy in a wasteful manner;
• Breach published national, state, or local standards relating to solid waste or litter control; or
• Extend a sewer trunk line with capacity to serve new development.

4.1.11.2.2. Impacts of the Proposed Action

Extending utility electrical service to the Project area would require the "overbuilding" of approximately sixteen (16) miles of existing IID 34.5 kV transmission line with a new 92 kV/34.5 kV transmission line in the corridor from Interstate Highway 8 to the existing transmission line's intersection with Indian Pass Road. In addition, in the Project ancillary area, approximately 3.7 miles of new 92 kV transmission line, underbuilt with a 13.2 kV distribution line, would be constructed from the intersection with the overbuilt 92 kV/34.5 kV transmission line to a step-down substation to the constructed in the Project mine and process area. The existing 34.5 kV transmission line would remain in service while the overbuilt 92 kV/34.5 kV transmission line was being built, so there would be no interruption of service for existing customers. Following the completion of mining and reclamation, the 92 kV/13.2 kV transmission line would be removed, but the overbuilt 92 kV/34.5 kV transmission line would remain under the ownership of the local utility. Because there would be no interruption in service, and the electrical utility system would be upgraded, there would be a net positive effect on the electric utility system.

During periods of utility service interruption, an on-site, $750 kW, diesel-powered generator would be used to provide emergency power for essential loads and services.

No telephone utility services are directly available to the Project area. A telephone communications relay to existing Black Mountain communication facilities would be installed to provide telephone service to the offices and maintenance shop via a microwave system which would be located within the Project area. Field communications would be provided by an FM mine communication system. The use of the microwave system and/or the FM mine communication system should not interfere with pilot communications during military overflights of the Project area and vicinity since these systems would be on different frequencies. This would not be a significant effect of the Proposed Action.

No utility-provided natural gas service is available to the Project area, nor would the existing system be adversely affect in other areas by the Proposed Action.

No utility-provided water services are available to the Project area. Water for mine operations and fire protection requirements would be produced from ground water wells constructed southwest of the Project area and piped in a buried pipeline to the Project area. The produced water would be stored in an on-site water storage tank for mining and fire protection requirements. Water collected in the open pits would be used where possible for roadway dust suppression purposes. Accordingly, there would be no adverse effect on water utility systems as a result of the Proposed Action.

The Proposed Action is not expected to generate significant population growth (see Section 4.1.10.2), and therefore any significant demand for local utility services, in the communities in which any Project employees and/or contractors, and their respective families, who may relocate for their job with the Project.

All portable and salvageable structures would be removed and taken off-site. Any permanent below-grade structures and all foundations would be removed, except the buried water pipeline and the process pond liners, and disposed of in a landfill authorized to accept these materials. All surplus materials, storage containers and trash would be transported to a landfill authorized to accept this material. The remaining waste products, and all surplus fuel oil and other materials, would be removed from the Project area and disposed of according to then-current state and federal regulations. Given the relatively small volumes of waste to be disposed of off-site, the Proposed Action would not result in a significant effect on the local and regional landfills and regulated or hazardous waste treatment or disposal facilities.

4.1.11.2.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.11.2-1: Applicant shall make available an on-site, diesel-fuel generator to meet emergency power needs for essential loads and services during periods of utility-provided electrical service interruption.
• 4.1.11.2-2: Applicant shall, at the end of the active life of the Project, remove all below-grade structures and all foundations, including the process pond liners; transport all surplus materials, storage containers and trash to a reuse or recycle facility, or to a landfill, authorized to accept this material; remove all remaining non-mining waste products, all surplus fuel oil, and other materials from the Project mine and process area and dispose of them according to then-current state and federal regulations.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.11.2-3: Applicant shall acquire the necessary approvals of the BLM, Imperial Irrigation District, and other appropriate agencies to construct the 92 kV transmission line over the existing 34.5 kV transmission line, and shall design, construct and maintain this transmission line in accordance with the conditions of these permits, including avoiding the disturbance of any new surface areas during construction.

Mitigation Measures Proposed to Avoid or Reduce Potentially Significant Impacts:

No measures are proposed or recommended.

Other Mitigation Measures (These are measures which may further reduce the impacts of certain effects which are below the level of significance without mitigation):

• 4.1.11.2-4: Applicant shall work with the USMC to ensure that neither the microwave communication system nor the Project FM mine communication system interfere with military overflight communications.

4.1.11.2.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in the consumption of utility-provided electrical power, which would not be adverse or significant. No other public utility services (except utility-provided telephone service, once connected with the microwave communication system) would be utilized by the Project, and the potential adverse effects of the Project communication systems on USMC use of the Project area would be mitigated to insignificance. Therefore, the effects of the Proposed Action on utility services would not exceed the level of significance.

4.1.11.3. Public Services

4.1.11.3.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Create a substantial demand for public services.

4.1.11.3.2. Impacts of the Proposed Action

No public or community services are available in the Project area. Septic treatment systems with leach drain fields would be constructed near the office and shop facilities, near the processing and laboratory facilities, and near the lime storage facilities. Produced ground water stored on the Project mine and process area would be used for commodes and hand-washing. Bottled water would be provided for drinking water.

The Project mine and process area is located on the township line between T.13S., R.21E. and T.14S., R.21E., and between eight (8) and nine (9) GLO/BLM Cadastral Survey monuments are likely located within the Project mine and process area along the township line. (None of the sections adjoining the township line within the Project mine and process area are surveyed or monumented.) Although some of these township line monuments may be able to be protected and maintained, damage or destruction to others within the Project mine and process area is inevitable since several are located within the projected pit or waste rock stockpile boundaries.

The few Project employees and contractors, and their respective families, who may relocate to regional communities would produce a very small increase in the demand for public and community services. Most of these families would be expected to reside in either Imperial County, California or Yuma County, Arizona. Any costs associated with these minor increases in demand for public or community services would be off-set by the additional property taxes and sales taxes provided to the communities and counties by the Project and Project employees. The Proposed Action would thus not result in a significant increase in population nor generate significant new demand for public or community services.

4.1.11.3.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.11.3-1: Applicant shall provide an on-site septic system for wastewater treatment, which shall be removed upon completion of Project activities.
• 4.1.11.3-2: When no longer required for Project operations, Applicant shall remove that portion of the 92 kV/13.2 kV transmission line owned by the Project.
• 4.1.11.3-3: Applicant shall provide potable water for hand washing and drinking purposes.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.11.3-4: Applicant shall obtain necessary permit(s) for on-site sanitary facilities from the Imperial County Department of Health Services.
• 4.1.11.3-5: To the extent feasible, all GLO/BLM Cadastral Survey monuments shall be avoided and protected from any accidental damage or destruction. All monuments which may be subject to either intentional or accidental damage or destruction within the Project mine and process area shall be perpetuated by the installation and survey of witness monuments, subject to the prior approval of the survey by the BLM Cadastral Survey and conformance with the applicable California codes, and documented with a record of survey.

Incorporated to Avoid or Reduce Potentially Significant Effects:

No measures are proposed or identified.

4.1.11.3.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would result in a very small increase in demand for public services, but these effects would be far below the level of significance.

4.1.12. Emergency Services and Public Safety

4.1.12.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Create a potential health hazard or involve the use, production, or disposal of materials which pose a hazard to people or animal or plant populations in the area affected;
• Interfere with emergency response plans or emergency evacuation plans.

4.1.12.2. Impacts of the Proposed Action

Design elements of the Project would minimize the need for off-site emergency services. The Proposed Action would not require routine patrol services by the police, as on-site personnel would patrol the Project mine and process area 24-hours per day, providing security. The Project heap leach pad, process facility, and solution ponds would be fenced with chain-link and barbed wire to prevent unlawful access. "No trespassing" signs and other warnings would be strategically located along the fenced perimeter of the Project mine and process area and the fenced ground water well sites. The "No trespassing" signs and fences would be removed following release of the reclamation bond. If needed, police services would be provided by the Imperial County Sheriff's Department. The nearest sheriff's substation is located in Winterhaven, approximately 30 road miles from the Project mine and process area.

Project facilities would be equipped with on-site fire protection systems. Fire services would also be available from the Imperial County Fire Department station at Winterhaven.

Mine chemicals/blasting agents and associated explosives would be stored in locked magazines in compliance with ATF and MSHA safety standards.

Relatively large volumes of hazardous, and potentially hazardous, chemicals would be transported to, and stored within, the Project mine and process area, including: blasting agents and explosives; solid sodium cyanide (during transportation) and liquid sodium cyanide (stored on-site); sodium hydroxide; hydrochloric acid; polymaleic acid; ammonium nitrate; diesel fuel; unleaded gasoline; and motor oil. The transport, storage, and handling of these materials have the potential to create adverse effects from spills into the environment and impact the safety of the public and Project employees.

Some of the chemicals and hazardous materials to be stored in the Project mine and process area are incompatible and reactive substances. In particular, a spill or mixing of sodium cyanide with an acid would result in the release of toxic hydrogen cyanide gas. The Proposed Action states that cyanide chemicals and acids would never be stored near each other, and the Project would implement triple-redundant procedures to ensure an event would not happen (Personal Communication, Steve Baumann, Glamis Imperial, 1997). Further, the use of these chemicals is a standard and common practice and a recognized potential hazard at precious metal mines using the heap leach process, and a potential hazard which employee training and good handling practices would be expected to prevent. It is extremely unlikely that the use of these chemicals within the Project mine and process area would pose any risk to individuals off-site. Therefore, the potential for the Proposed Action to create a hydrogen cyanide gas health hazard would be below the level of significance.

There would be a potential for public safety-related impacts due to the transport of hazardous chemicals to the Project area via public highways and access roads. The probability of hazardous chemical spillage occurring due to a transport accident is considered low, but the potential for occurrence cannot be entirely eliminated. The potential for a spill of sodium cyanide during transportation to the Project mine and process area to create result in a substantial hazard to public safety or the environment is extremely low since the sodium cyanide would be transported to the Project in a solid, briquette form in sealed tanker trucks. A hazardous material spill contingency plan would be prepared by the Applicant to respond to potential hazardous material and chemical spills within the Project area. All transporters of hazardous materials for the Project are governed by State and federal regulations regarding the transportation of hazardous materials on public highways. Hazardous materials transporters are required to have special permits and licenses, and receive extensive hazardous materials (HAZMAT) training which prepares them to effectively manage spill incidents. Trucks which transport hazardous materials are equipped with safety equipment and comprehensive emergency response instructions to ensure proper action is taken in the event of an emergency. Although the transporter is responsible for managing and cleaning up any spill incidents, the California Highway Patrol would respond to and provide assistance for any spill incidents which occur on highways or roads in unincorporated portions of the Imperial County. Additionally, the nearest District Fire Station would initially respond to a hazardous material spill incident to provide immediate assistance, with follow-up response provided by the Imperial County Fire Department HAZMAT Team. The potential risk of a public safety hazard resulting from spills of hazardous chemicals being transported to the Project area would be below the level of significance.

Following completion of mining and final reclamation, the East Pit would remain open, and the steep sidewalls of the open pit would result in a continuing potential public safety risk. This public safety risk would be increased if the open pit contained a pit lake, which might attract the public to attempt to enter the pit. However, the Proposed Action includes measures to reduce or eliminate the formation of a pit lake (see Section 2.1.3 and Section 4.1.3.1.2), and states that the open East Pit would be barricaded with large boulders around the rim to prevent vehicular access and discourage pedestrian access by the public over slopes which could constitute a hazard (see Section 2.1.11.2.2). The barricade would consist of boulders averaging approximately four (4) feet in diameter, which would be stacked into a continuous wall no less than eight (8) feet high. This "wall" would be set back from the edge of the pit by no less than 100 feet. In addition, the uppermost ten (10) feet of the pit slope would slope no greater than 2H:1V (30 degrees), and would terminate at its lower side into a horizontal bench no less than ten (10) feet wide. With this construction, the effects of the Project on public safety from the remnant open pit would be below the level of significance.

Should mining be terminated prior to the complete backfilling of either the West Pit or the Singer Pit, these pits would not be barricaded under the Proposed Action, and no measures would be taken to reduce or eliminate the formation of a pit lake in the West Pit. This would constitute a significant effect on public safety.

4.1.12.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

Although the assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts, these measures are expressly identified below to facilitate review and implementation. Mitigation measures, if any, which are proposed to avoid or reduce potentially significant effects are separately identified.

Measures Incorporated by Project Design Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.12-1: Applicant shall provide appropriate levels of on-site security, fire protection services, and emergency first-aid medical services.
• 4.1.12-2: Applicant shall construct and maintain a fence around the perimeter of the Project mine and process area over the life of the Project, and a chain-link fence, no less than six (6) feet in height, with one (1) foot of barbed wire at the top, around the ore leach pad, process facilities, to prevent the public from accessing these facilities.
• 4.1.12-3: Sodium cyanide shall be shipped to, and received at, the Project mine and process area in solid, briquette from in the manufacturer's dry bulk trucks, and be put into solution directly from the dry bulk trucks at the Project mine and process area process facility.
• 4.1.12-4: Before removal of the perimeter fence at the end of the active life of the Project, Applicant shall construct around the rim of the open East Pit a barricade with large boulders to prevent vehicular access and discourage pedestrian access by the public over slopes which could constitute a hazard. The barricade shall consist of boulders averaging approximately four (4) feet in diameter, which shall be stacked into a continuous wall no less than eight (8) feet high. This "wall" shall be set back from the edge of the pit by no less than 100 feet. In addition, the uppermost ten (10) feet of the pit slope shall slope no greater than 2H:1V (30 degrees), and shall terminate at its lower side into a horizontal bench no less than ten (10) feet wide.
• 4.1.12-5: Applicant shall post no trespassing and hazardous chemical signs, in both English and Spanish, at strategic locations along perimeter locations of the Project mine and process area perimeter fence and the process facilities barbed wire-topped chain-link fence, respectively.
• 4.1.12-6: Applicant shall prepare a hazardous material spill/release contingency plan and provide appropriate training to all Project employees on the proper response to potential chemical releases.
• 4.1.12-7: Applicant shall prepare an emergency response contingency plan which provides for actions to be taken in the event of an injury accident, hazardous materials release, fire, flash flooding on Indian Pass Road, or other emergency situation. The emergency response contingency plan shall include emergency phone numbers and services available for both surface and air transport of injured employees. The emergency contingency response plan shall incorporate protocols acceptable to the BLM, ICPWD, and the Imperial County Sheriff's Office for dealing with flash floods and public safety on Indian Pass Road. The protocols shall address notification of agencies and closures of Indian Pass Road.

Measures Incorporated by Regulation Which Avoid or Reduce Potentially Significant Impacts:

• 4.1.12-8: Applicant shall prepare and maintain a hazardous material business plan in conformance with the requirements of Imperial County.
• 4.1.12-9: Applicant shall conform with all applicable safety regulations required by the Mine Safety and Health Administration (MSHA), Occupational Safety and Health Administration (OSHA), and California Occupational Safety and Health Administration (Cal-OSHA ).

Incorporated to Avoid or Reduce Potentially Significant Effects:

See also those measures described in Section 4.1.5.4 designed to eliminate the possibility of a pit lake to mitigate potential impacts to wildlife.

• 4.1.12-10: Before removal of the perimeter fence at the end of the active life of the Project, Applicant shall construct around the rim of the all open pit(s) a barricade with large boulders to prevent vehicular access and discourage pedestrian access by the public over slopes which could constitute a hazard. The barricade shall consist of boulders averaging approximately four (4) feet in diameter, which shall be stacked into a continuous wall no less than eight (8) feet high. This "wall" shall be set back from the edge of the pit by no less than 100 feet. In addition, the uppermost ten (10) feet of the pit slope shall slope no greater than 2H:1V (30 degrees), and shall terminate at its lower side into a horizontal bench no less than ten (10) feet wide.

4.1.12.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would have the unavoidable indirect potential to adversely effect worker and/or public safety through the accidental spill or release of hazardous substances either in transport to the Project area or from activities within the Project area. This unavoidable potential effect is considered less than significant.

The mitigated effects of the Proposed Action on all emergency services and public safety is below the level of significance.

4.1.13. Other Resources

4.1.13.1. Assumptions and Assessment Guidelines

The assessment of impacts assumes the implementation of those measures incorporated into the project design or required by regulation which avoid or reduce potentially significant impacts.

The Proposed Action would normally have a significant effect on the environment if it would:

• Convert prime agricultural land to non-agricultural use or impair the agricultural productivity of prime or unique agricultural land.
• Result in a substantial adverse impact to a designated wild or scenic river.
• Result in a substantially disproportionate share of the negative environmental impacts of a project on minority populations and low-income populations.

4.1.13.2. Impacts of the Proposed Action

Because neither the Project area nor the overbuilt 92 kV/34.5 kV transmission line corridor is in or adjacent to an area of prime or unique farmland or a designated wild or scenic river, the Proposed Action would have no impacts to either of these resources.

Environmental Justice and Sacred Sites:

Environmental Justice Executive Order: Executive Order 12898 (Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations) was signed by President Clinton on February 11, 1994 and became effective on that date. This Executive Order required each federal agency to make achieving "environmental justice" part of its mission by identifying and addressing, as appropriate, disproportionately high and adverse human health or environmental effects on minority populations and low-income populations in the United States and its territories and possessions. Agency responsibilities under the Executive Order apply equally to Native American programs.

Relevant to Environmental Justice is the nature of the proposed action and requisite law involved. A mining project such as the Imperial Project allows for limited agency discretion, practically as well as regulatorally (see Section 1.6.1). The location and layout of a mine is a consequence of the nature and formation of mineral ore body. Section 3 of the 1872 Mining Act (30 USC 26) gives exclusive right of "possession and enjoyment" of the surface within the boundaries of a valid mining claim to the mining claimant. The right of the United States to manage surface resources but not locatable minerals on a valid mining claim was also authorized, as long as such management did not materially interfere with the operation of the mining claim (30 USC 612(b)).

Population in the Affected Area: The Project area lies within an unpopulated, unincorporated area of Imperial County. The nearest residence is located at Gold Rock Ranch, a mobile home (21 sites)/RV park (14 sites) located approximately seven (7) miles southwest of the Project mine and process area (see Section 5.2.2.2). No other residences exist within ten (10) miles of the Project mine and process area. The Project mine and process area is ten (10) miles from the closest point of the Ft. Yuma Indian Reservation, and the principal concentrations of housing on the reservation are over sixteen (16) miles away.

Impact: Quechan tribal members expressed concern that construction and operation activities in the Project mine and process area would impact an area of religious, cultural, and educational value, which has been termed the Indian Pass-Running Man ATCC (see Section 3.6.2.4). This area was used as recently as the 1940's for specific religious observances that can only occur in this place, and Quechan tribal members have stated that they plan to conduct such observances at this location in the future. The Indian Pass-Running Man ATCC is viewed as necessary for religious practitioners to gain requisite knowledge for continuation of Quechan religious beliefs and practices, and necessary for teaching Indian youth about tribal history, religion, and culture. Quechan tribal members have stated that the development of the Project pits, heap, and waste rock stockpiles would destroy the ability of the Quechan to perform their religious, cultural and educational practices.

Quechan tribal members have also expressed concern for the cumulative impacts of both recent developments and historic activities on sites of cultural and religious significance (see Section 5.3.4 for a discussion of cumulative impacts to cultural sites and religious values).

The environmental consequences of the Proposed Action (see Section 4.1.1 through Section 4.1.12) will not result in any conditions, such as reduced air quality, noise exposure, or transportation of hazardous or other materials, which could produce a substantial direct or indirect impact to human health or environmental effects to any population residing at the distances identified above from the Project area.

Consultation with Native American Pursuant to Executive Order 12898: The BLM, through the El Centro Resource Area Manager, initiated an extensive consultation process with the Quechan Tribe in 1996 in conformance with NHPA, AIRFA, and the Executive Order 13007 (Sacred Sites). Based upon comments, particularly those by the Quechan Tribe, the November 1996 Draft EIS was withdrawal and a new Draft EIS prepared (see Section 1.5 and Chapter 7). As part of the process to prepare this new Draft EIS, the Quechan were requested to participate in resurveying the area of the Proposed Action, and an extensive effort to document Quechan concerns was initiated through the Tribal Cultural Committee. Particular individuals identified by the Tribal Cultural Committee provided cultural and religious information (see Section 3.6).

4.1.13.3. Measures Incorporated by Project Design and Regulation and Mitigation Measures

No mitigation measures are required.

4.1.13.4. Unavoidable Adverse Effects and Level of Significance After Mitigation

The Proposed Action would have no unavoidable adverse effects on other resources.

4.2. West Pit Alternative

As discussed in Section 2.2.1, the West Pit Alternative would eliminate the East Pit, the East Waste Rock Stockpile, and the East Pit West and East Pit East drainage diversions within the Project mine and process area. The size of the leach pad, the process area, and the haul and maintenance roads would also be reduced. Only 150 million tons of material would be mined. The total surface area of disturbance within the Project mine and process area would be reduced from 1,302 acres under the Proposed Action to approximately 795 acres (see Table 2.6), and the Project life would be decreased from the approximately twenty (20) years under the Proposed Action to about ten (10) years under the West Pit Alternative. Under the West Pit Alternative, the Singer Pit would not be backfilled, and the West Pit would only be partially backfilled with waste rock from the Singer Pit. Both the South Waste Rock Stockpile and the heap would be constructed to a height of approximately 300 feet, the same height as under the Proposed Action. All environmental protection measures and reclamation activities would be conducted as under the Proposed Action.

4.2.1. Geology and Mineral Resources

4.2.1.1. Impacts of the West Pit Alternative

The West Pit Alternative would leave the precious metal resources in the East Pit area unmined and undeveloped. Because the West Pit would only be partially backfilled, any residual potential mineral resources remaining in the West Pit would be more available to be developed in the future than were the pit to be completely backfilled. Neither of these differences create a significant environmental effect. Other than these, there would be no substantive difference in the impacts of the West Pit Alternative on geology and mineral resources from those identified for the Proposed Action (see Section 4.1.1.2). The effects of the West Pit Alternative on geology and mineral resources would be below the levels of significance.

4.2.1.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on geology and mineral resources would be the same as those identified for the Proposed Action (see Section 4.1.1.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on geology and mineral resources would remain below the level of significance.

4.2.2. Soil Resources

4.2.2.1. Impacts of the West Pit Alternative

The West Pit Alternative would decrease the total area of surface disturbance from the 1,362 acres under the Proposed Action to 853  acres, an approximate 37 percent reduction. This would translate to an approximate 37 percent reduction in the loss of soil resources (see Section 4.1.2.2). Other potential impacts, such as erosion within the West Pit Alternative project mine and process area, would be the same in effect, although slightly reduced in magnitude, as those identified for the Proposed Action in Section 4.1.2.2. There would be a two (2) acre (six [6] percent) reduction in the acreage of soils disturbed in the West Pit Alternative project ancillary area because only two (2) ground water wells would be drilled, but no change in the overbuilt 92 kV/34.5 kV transmission line corridor. The effects of the West Pit Alternative on soil resources would also be below the levels of significance.

4.2.2.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on soil resources would be the same as those identified for the Proposed Action (see Section 4.1.2.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on soil resources would remain below the level of significance.

4.2.3. Hydrologic Resources

4.2.3.1. Impacts of the West Pit Alternative

Surface Water

The West Pit Alternative would eliminate the need to construct the East Pit West and East Pit East diversion channels, and would eliminate any impact to these existing surface drainage channels. The remaining impacts to surface water diversions would not be significant. The East Pit would not be mined, the East Waste Rock Stockpile would not be built, and the heap would be reduced in size, so there would be less precipitation contained within the West Pit Alternative project mine and process area and not discharged into surface runoff. The impact to sediment production of the facilities constructed under the West Pit Alternative would be less than significant. Since the East Pit would not be mined, the potential for seeps or a pit lake in the East Pit would be completely eliminated. However, since the West Pit would not be completely backfilled under the West Pit Alternative, and the West Pit is projected to be mined to a depth below the existing ground water level, seeps, and possibly (but not likely) a pit lake, could form in the West Pit. Since the Singer Pit would not be mined below the elevation of the ground water table , no pit lake could form from ground water inflows as a result of not backfilling the Singer Pit. The impacts of the West Pit Alternative from ground water inflows would be below the level of significance. The West Pit Alternative would also result in a reduction of 29 percent, to 55.2 acres (LSA 1997b), in the area of "waters of the United States" which would be dredged or filled over the Proposed Action. This impact would also be below the level of significance (see Section 4.1.3.1.2).

Ground Waters

The West Pit Alternative would produce ground water for operations at a rate somewhat less than that under the Proposed Action, and from a maximum of only two (2) ground water wells. Also, since the West Pit Alternative would have an estimated life of only half that of the Proposed Action, the total amount of water produced would be substantially less than half of that produced under the Proposed Action. However, because most of the ground water table drawdown occurs early in the ground water production process, the ground water table drawdown in the area surrounding the ground water production wells would be only slightly reduced from the Proposed Action. Recovery to pre-project levels would be substantially earlier, however, because pumping would cease sooner. Neither impact would be above the level of significance. The effects of the West Pit Alternative on ground water quality and pit water quality would not be different than that of the Proposed Action, although the likelihood of any impacts to ground water quality or pit water quality would be further reduced because of the reduction in size of the heap pad and the elimination of the East Pit (see Section 4.1.3.2.2).

4.2.3.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on surface water and ground water resources would be the same as those identified for the Proposed Action (see Section 4.1.3.1.3 and Section 4.1.3.2.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on surface water and ground water resources would remain below the level of significance.

4.2.4. Air Resources

4.2.4.1. Impacts of the West Pit Alternative

The impacts of the West Pit Alternative on air resources would be very similar to, but slightly reduced from, the impacts to air resources which would result from the implementation of the Proposed Action. The biggest difference would be that the impacts from the West Pit Alternative would be reduced in duration to only ten (10) years from twenty (20) years under the Proposed Action (see Section 4.1.4.2). The effects of the West Pit Alternative on air resources would be below the level of significance except for PM₁₀. Although the effects of the West Pit Alternative would be mitigated to below the level of significance, the West Pit Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would be a cumulatively significant effect.

4.2.4.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on air resources would be the same as those identified for the Proposed Action (see Section 4.1.4.3). No other measures are proposed to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on air resources would remain below the level of significance except for PM₁₀. Although the effects of the West Pit Alternative would be mitigated to below the level of significance, the West Pit Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would remain a cumulatively significant effect.

4.2.5. Biological Resources

4.2.5.1. Impacts of the West Pit Alternative

Vegetation and Plant Habitat

The West Pit Alternative would reduce the total surface disturbance from 1,362 acres under the Proposed Action to 853 acres, a reduction of 37 percent. The loss of shrub/scrub vegetation habitat would be reduced from approximately 1,260 acres under the Proposed Action to approximately 719 acres, and the loss of shrub/tree vegetation habitat would be reduced from approximately 87 acres under the Proposed Action to approximately 52 acres. In addition, the amount of surface area not reclaimed (the West Pit slopes not covered by backfill) would decrease from 165 acres under the Proposed Action to approximately 88 acres, a reduction of 47 percent. The time required to complete final reclamation would also be reduced to approximately ten (10) years.

Although the magnitude of the impacts to vegetation and plant habitat from this reduced surface disturbance would be reduced by 37 percent, the impacts themselves would be the same as the Proposed Action, and would remain below the level of significance. Other impacts to vegetation and plant habitat (from dust, ground water pumping, surface channel diversions, and sensitive plants) would also be reduced proportionately from those of the Proposed Action (see Section 4.1.5.2), and would remain below the level of significance.

Wildlife, Wildlife Habitat and Wildlife Movement

The reduced area of surface disturbance resulting from the West Pit Alternative would also reduce the amount of wildlife habitat lost over that of the Proposed Action. Approximately 719 acres of desert succulent scrub habitat and 52 acres of microphyll woodland habitat would be lost. Approximately 152 acres of the 947-acre West Pit Alternative project mine and process area would be undisturbed. Most of this habitat loss would be temporarily, until the completion of final reclamation (and subsequent vegetation recovery). However, approximately one-half (2) of the disturbed microphyll woodland habitat would be reclaimed not as microphyll woodland habitat but as desert succulent scrub habitat, and the 88 acres of the West Pit slopes would not be reclaimed.

Although the magnitude of the impacts to wildlife and wildlife habitat from this reduced surface disturbance would be reduced by 37 percent, the impacts themselves would be the same as the Proposed Action, and would remain below the level of significance. Other impacts from the West Pit Alternative on wildlife and wildlife habitat (from ground water pumping, surface channel diversions, and sedimentation) would also be reduced proportionately from those of the Proposed Action (see Section 4.1.5.3), and would remain below the level of significance.

The West Pit Alternative would mine and leave open or partially open the 33-acre Singer Pit and the 110-acre West Pit. This would reduce the potential area over which wildlife could be killed or injured by falls or opportunistic predators from the 198-acres left open under the Proposed Action. This impact would be below the level of significance.

The West Pit Alternative would have a life of only approximately ten (10) years, which would reduce the exposure of wildlife and wildlife habitat to impacts from vehicles, hazardous materials, noise, human presence, etc., by about one-half (2) over the Proposed Action. These effects would be below the level of significance.

Although reduced from the Proposed Action, the impacts of the West Pit Alternative on the desert tortoise would remain above the level of significance.

4.2.5.2. Mitigation Measures

Measures to reduce the effects of the West Pit Alternative on biological resources would be the same as those measures identified for the Proposed Action (see Section 4.1.5.4), except as altered to reflect the reduction in area or time from the Proposed Action. With implementation of the identified measures, the mitigated effects of the West Pit Alternative on biological resources would be below the level of significance.

4.2.6. Cultural and Paleontological Resources

4.2.6.1. Impacts of the West Pit Alternative

The West Pit Alternative would create approximately 38 percent less surface disturbance than the Proposed Action within the Project area, and identical surface disturbance within the overbuilt 92 kV/34.5 kV transmission line corridor. However, the density of cultural resource features determined eligible for the NRHP and identified within the Project mine and process area is substantially higher on the west side, in the area of the West Pit and South Waste Rock Stockpile, than on the east side, in the area of the East Pit and the heap leach pad and process facilities. Consequently, the impacts of the West Pit Alternative on cultural resources determined eligible for the NRHP appear to be only slightly less than the impacts to these same type of cultural resources which would result from the implementation of the Proposed Action. The impacts of the West Pit Alternative would remain above the level of significance. The West Pit Alternative would do little to reduce the adverse effects on the Indian Pass-Running Man ATCC, and remaining impacts would be above the level of significance. The effects of the West Pit Alternative on those cultural resources identified within the overbuilt 92 kV/34.5 kV transmission line corridor would be identical to the Proposed Action, and above the level of significance.

4.2.6.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on cultural resources would be the same as those identified for the Proposed Action (see Section 4.1.6.3). Measures to reduce the significant effects of the West Pit Alternative on cultural resource features identified within the overbuilt 92 kV/34.5 kV transmission line corridor, or within the West Pit Alternative project area, which were determined eligible for the NRHP under criterion "D" would be identical to those identified for the Proposed Action. The mitigated impacts would be reduced below the level of significance. Measures to reduce the significant effects of the West Pit Alternative on cultural resource features determined eligible for the NRHP under criteria "A", "B," or "C" which were identified within the West Pit Alternative project area, or to reduce the significant effects of the West Pit Alternative on the Indian Pass-Running Man ATCC, would be identical to those identified for the Proposed Action. The mitigated effects of these impacts would remain above the level of significance and be unavoidable.

4.2.7. Visual Resources

4.2.7.1. Impacts of the West Pit Alternative

The West Pit Alternative would result in visual contrasts created by changes in line and form from the creation of new structures and facilities, altered surface colors, textures and vegetation cover, and changes in topography similar to the Proposed Action (see Section 4.1.7.2). Because of the smaller area of surface disturbance, the elimination of one waste rock stockpile, and the smaller size (but not height) of the remaining waste rock stockpile and heap, the magnitude of these effects would be reduced from some viewpoints, but not from others. The view of the West Pit Alternative project mine and process area from KOP #1 and KOP #4 would be very similar to the view of the Proposed Action from these same points (see Figure 4.3 and Figure 4.9, respectively) since the view of the West Pit Alternative is principally of the upper portions of the south ends of the South Waste Rock Stockpile and the heap, which change very little from the Proposed Action. The view of the West Pit Alternative project mine and process area from KOP #2 and KOP #3 (see Figure 4.5 and Figure 4.7, respectively) would show the reduced surface disturbance and the elimination or reduction of each of the features within the West Pit Alternative project mine and process area over the Proposed Action. However, the effects of the West Pit Alternative on line and form would remain, like the Proposed Action, above the level of significance. Impacts to visual resources from the West Pit Alternative from the lighting of mine and process areas and visibility reduction would remain essentially identical to the Proposed Action (see Section 4.1.7.2), except that they would be shorter in duration by about ten (10) years. Like the Proposed Action, the impacts of visibility reduction would be below the level of significance, while the impacts of lighting would be above the level of significance.

4.2.7.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design which eliminate potentially significant effects on visual resources would be the same as those identified for the Proposed Action (see Section 4.1.7.3). Measures to reduce the significant effects of the West Pit Alternative on lighting would also be the same as those measures identified for the Proposed Action. With implementation of the identified measures, the mitigated effects of the West Pit Alternative on visual resources from visibility reduction and lighting would be below the level of significance. The mitigated effects of the West Pit Alternative on visual resources from changes in line and form would remain above the level of significance.

4.2.8. Noise

4.2.8.1. Impacts of the West Pit Alternative

The noise generated by the West Pit Alternative would be essentially identical to the noise generated by the Proposed Action, except that the noise would cease earlier. The impacts of the generated noise on receptors would also be essentially the same as that described for the Proposed Action (see Section 4.1.8.2), except that the impacts would also cease earlier. The noise impacts of the West Pit Alternative would be below the levels of significance.

4.2.8.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects of noise would be the same as those identified for the Proposed Action (see Section 4.1.8.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The noise effects of the West Pit Alternative would remain below the level of significance.

4.2.9. Land Use

4.2.9.1. Impacts of the West Pit Alternative

The compatibility of the West Pit Alternative with existing land uses and adopted land use policies and plans would be essentially identical to that of the Proposed Action (see Section 4.1.9.2). Blasting during mining operations could be a significant potential hazard to low-flying military aircraft using the general area for training exercises (although this impact would end in approximately ten (10), rather than twenty (20), years). The West Pit Alternative's impact on recreational use of the area, including wilderness use, would be essentially identical in type, but slightly reduced in scale and duration, from that of the Proposed Action, since the West Pit Alternative would exclude recreational use only over 947 acres for approximately ten (10) years instead of 1,571 acres for approximately twenty (20) years. These impacts would be below the level of significance.

4.2.9.2. Mitigation Measures

Measures to ensure the compatibility of the West Pit Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area would be the same as those measures identified for the Proposed Action (see Section 4.1.9.2). With implementation of the identified measures, the mitigated level of compatibility of the West Pit Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area, would be below the level of significance.

4.2.10. Socioeconomics

4.2.10.1. Impacts of the West Pit Alternative

The West Pit Alternative would have a net beneficial socioeconomic effect which would be reduced from the net beneficial socioeconomic effect of the Proposed Action (see Section 4.1.10.2). These effects would be below the level of significance. Although the number of jobs created under the West Pit Alternative would be approximately the same as the Proposed Action, the length of these jobs would be decreased from approximately twenty (20) years to ten (10) years. Initial capital expenditures for (and thus sales taxes paid under) the West Pit Alternative would be approximately the same as the Proposed Action. Recurrent, annual expenditures (such as annual capital expenditures of approximately $1.7 million (and $0.13 million in sales taxes), non-capital expenditures of approximately $26 million, and property taxes of between $200,000 and $600,000) would be reduced by one-half (2) from that of the Proposed Action because of the decreased operating life.

4.2.10.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.2.11. Roads and Public Services

4.2.11.1. Impacts of the West Pit Alternative

The West Pit Alternative would result in an essentially identical increase in traffic as the Proposed Action (see Section 4.1.11.1.2), except that the effects would occur for only ten (10), rather than twenty (20), years. These effects would be below the level of significance. The West Pit Alternative would require the realignment of Indian Pass Road to the identical degree and timing as the Proposed Action. These impacts would also be below the level of significance. The West Pit Alternative would also create a potential impact from "spur" roads, to a similar extent and degree as the Proposed Action. This impact would be below the level of significance.

The West Pit Alternative would have a similar impact on utilities as the Proposed Action. Because of the reduced size of the project, less non-mining waste would be generated (see Section 4.1.11.1.2). All impacts on utilities would be below the level of significance. The West Pit Alternative would also produce impacts on public services similar to the Proposed Action (see Section 4.1.11.3.2). Because of the reduced surface area to be disturbed, there would be fewer cadastral monuments which may be destroyed. These impacts would be below the level of significance.

4.2.11.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on roads, utilities and public services would be the same as those measures identified for the Proposed Action (see Section 4.1.11.1.3, Section 4.1.11.2.3, and Section 4.1.11.3.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on roads, utilities and public services would remain below the level of significance.

4.2.12. Emergency Services and Public Safety

4.2.12.1. Impacts of the West Pit Alternative

The West Pit Alternative would have essentially identical impacts on emergency services and public safety as would the Proposed Action (see Section 4.1.12.2), although the life of the West Pit Alternative would be ten (10), rather than twenty (20), years. Instead of the East Pit being left open following the completion of mining and reclamation, under the West Pit Alternative the Singer Pit and the West Pit would be left open. The effects of the West Pit Alternative on emergency services and public safety would be less than significant.

4.2.12.2. Mitigation Measures

Mitigation measures incorporated into the West Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on emergency services and public safety would be the same as those measures identified for the Proposed Action (see Section 4.1.12.3). No other measures would be necessary to reduce impacts of the West Pit Alternative below the level of significance. The effects of the West Pit Alternative on emergency services and public safety would be below the level of significance.

4.2.13. Other Resources

4.2.13.1. Impacts of the West Pit Alternative

The West Pit Alternative would have essentially identical impacts on other resources as would the Proposed Action (see Section 4.1.13), although the life of the West Pit Alternative would be ten (10), rather than twenty (20), years. The effects of the West Pit Alternative on other resources would be less than significant.

4.2.13.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.3. East Pit Alternative

As discussed in Section 2.2.2, the East Pit Alternative would eliminate the West Pit, the West Soil Stockpile, the West Pit West and West Pit East drainage diversions, and the relocation of Indian Pass Road within the Project mine and process area. The size of the leach pad, the South Waste Rock Stockpile, the associated areas of disturbance, and the haul and maintenance roads would also be reduced. Only 300 million tons of material would be mined. The total surface area of disturbance within the Project mine and process area would be reduced from 1,302 acres under the Proposed Action to approximately 1,126 acres (see Table 2.7), and the Project life would be decreased from the approximately twenty (20) years under the Proposed Action to about fourteen (14) years under the East Pit Alternative. Under the East Pit Alternative, the Singer Pit would be completely backfilled, and the East Pit would not be backfilled. The South Waste Rock Stockpile and the East Waste Rock Stockpile would still be constructed to approximately the same height (300 feet) as under the Proposed Action, but the heap would be constructed to a height of approximately 250 feet.

4.3.1. Geology and Mineral Resources

4.3.1.1. Impacts of the East Pit Alternative

The East Pit Alternative would leave the precious metal resources in the West Pit area unmined and undeveloped. This would not be a significant environmental effect. Other than this, there would be no substantive difference in the impacts of the East Pit Alternative on geology and mineral resources from those identified for the Proposed Action (see Section 4.1.1.2). The effects of the East Pit Alternative on geology and mineral resources would be below the levels of significance.

4.3.1.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on geology and mineral resources would be the same as those identified for the Proposed Action (see Section 4.1.1.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on geology and mineral resources would remain below the level of significance.

4.3.2. Soil Resources

4.3.2.1. Impacts of the East Pit Alternative

The East Pit Alternative would decrease the total area of surface disturbance from the 1,362 acres under the Proposed Action to 1,126 acres, an approximate 19 percent reduction. This would translate to an approximate 19 percent reduction in the loss of soil resources (see Section 4.1.2.2). Other potential impacts, such as erosion within the East Pit Alternative project mine and process area, would be the same in effect, although slightly reduced in magnitude, as those identified for the Proposed Action in Section 4.1.2.2. There would be a seven (7) acre (eighteen [18] percent) reduction in the acreage of soils disturbed in the East Pit Alternative project ancillary area because only three (3) ground water wells would be drilled and Indian Pass Road would not be relocated. There would be no change in the overbuilt 92 kV/34.5 kV transmission line corridor. The effects of the East Pit Alternative on soil resources would also be below the levels of significance.

4.3.2.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on soil resources would be the same as those identified for the Proposed Action (see Section 4.1.2.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on soil resources would remain below the level of significance.

4.3.3. Hydrologic Resources

4.3.3.1. Impacts of the East Pit Alternative

Surface Water

The East Pit Alternative would eliminate the need to construct the West Pit West and West Pit East diversion channels, and would eliminate any impact to these existing surface drainage channels. The remaining impacts to surface water diversions would not be significant. The West Pit would not be mined, the West Soil Stockpile would not be built, and the heap would be slightly reduced in size, so there would be slightly less precipitation contained within the East Pit Alternative project mine and process area and not discharged into surface runoff. The impact to sediment production of the facilities constructed under the East Pit Alternative would be less than significant. The impacts of the East Pit Alternative from ground water inflows would be below the level of significance. The East Pit Alternative would also result in a reduction of 17 percent, to 64.4 acres (LSA 1997b), in the area of "waters of the United States" which would be dredged or filled over the Proposed Action. This impact would also be below the level of significance (see Section 4.1.3.1.2).

Ground Waters

The East Pit Alternative would produce ground water for operations at a rate slightly less than that under the Proposed Action, and from a maximum of three (3) ground water wells. Also, since the East Pit Alternative would have an estimated life of approximately two-thirds (b) that of the Proposed Action, the total amount of water produced would be less than two-thirds (b) that produced under the Proposed Action. However, because most of the ground water table drawdown occurs early in the ground water production process, the ground water table drawdown in the area surrounding the ground water production wells would be only slightly reduced from the Proposed Action. Recovery to pre-project levels would be earlier, however, because pumping would cease sooner. Neither impact would be above the level of significance. The effects of the East Pit Alternative on ground water quality and pit water quality would not be different than that of the Proposed Action, although the likelihood of any impacts to ground water quality or pit water quality would be slightly reduced because of the reduction in size of the heap pad and the elimination of the West Pit (see Section 4.1.3.2.2).

4.3.3.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on surface water and ground water resources would be the same as those identified for the Proposed Action (see Section 4.1.3.1.3 and Section 4.1.3.2.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on surface water and ground water resources would remain below the level of significance.

4.3.4. Air Resources

4.3.4.1. Impacts of the East Pit Alternative

The impacts of the East Pit Alternative on air resources would be very similar to, but slightly reduced from, the impacts to air resources which would result from the implementation of the Proposed Action. The biggest difference would be that the impacts from the East Pit Alternative would be reduced in duration to only fourteen (14) years from twenty (20) years under the Proposed Action (see Section 4.1.4.2). The effects of the East Pit Alternative on air resources would be below the level of significance except for PM₁₀. Although the effects of the East Pit Alternative would be mitigated to below the level of significance, the East Pit Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would be a cumulatively significant effect.

4.3.4.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on air resources would be the same as those identified for the Proposed Action (see Section 4.1.4.3). No other measures are proposed to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on air resources would remain below the level of significance except for PM₁₀. Although the effects of the East Pit Alternative would be mitigated to below the level of significance, the East Pit Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would remain a cumulatively significant effect.

4.3.5. Biological Resources

4.3.5.1. Impacts of the East Pit Alternative

Vegetation and Plant Habitat

The East Pit Alternative would reduce the total surface disturbance from 1,362 acres under the Proposed Action to 1,126 acres, a reduction of 19 percent. The loss of shrub/scrub vegetation habitat would be reduced from approximately 1,260 acres under the Proposed Action to approximately 1,064 acres, and the loss of shrub/tree vegetation habitat would be reduced from approximately 87 acres under the Proposed Action to approximately 62 acres. The amount of surface area not reclaimed (the East Pit slopes not covered by backfill) would remain unchanged from the Proposed Action at 165 acres. The time required to complete final reclamation would also be reduced to approximately fourteen (14) years.

Although the magnitude of the impacts to vegetation and plant habitat from this reduced surface disturbance would be reduced by 19 percent, the impacts themselves would be the same as the Proposed Action, and would remain below the level of significance. Other impacts to vegetation and plant habitat (from dust, ground water pumping, surface channel diversions, and sensitive plants) would also be reduced proportionately from those of the Proposed Action (see Section 4.1.5.2), and would remain below the level of significance.

Wildlife, Wildlife Habitat and Wildlife Movement

The reduced area of surface disturbance resulting from the East Pit Alternative would also reduce the amount of wildlife habitat lost over that of the Proposed Action. Approximately 1,064 acres of desert succulent scrub habitat and 62 acres of microphyll woodland habitat would be lost. Approximately 203 acres of the 1,276-acre East Pit Alternative project mine and process area would be undisturbed. Most of this habitat loss would be temporarily, until the completion of final reclamation (and subsequent vegetation recovery). However, approximately one-half (2) of the disturbed microphyll woodland habitat would be reclaimed not as microphyll woodland habitat but as desert succulent scrub habitat, and the 165 acres of the East Pit slopes would not be reclaimed.

Although the magnitude of the impacts to wildlife and wildlife habitat from this reduced surface disturbance would be reduced by approximately 19 percent, the impacts themselves would be the same as the Proposed Action, and would remain below the level of significance. Other impacts from the East Pit Alternative on wildlife and wildlife habitat (from ground water pumping, surface channel diversions, and sedimentation) would also be reduced proportionately from those of the Proposed Action (see Section 4.1.5.3), and would remain below the level of significance.

The East Pit Alternative would mine and leave open the 198-acre East Pit, which is the same potential area over which wildlife could be killed or injured by falls or opportunistic predators as the Proposed Action. This impact would be below the level of significance.

The East Pit Alternative would have a life of approximately fourteen (14) years, which would reduce the exposure of wildlife and wildlife habitat to impacts from vehicles, hazardous materials, noise, human presence, etc., by about one-third (a) over the Proposed Action. These effects would be below the level of significance.

Although slightly reduced from the Proposed Action, the impacts of the East Pit Alternative on the desert tortoise would remain above the level of significance.

4.3.5.2. Mitigation Measures

Measures to reduce the effects of the East Pit Alternative on biological resources would be the same as those measures identified for the Proposed Action (see Section 4.1.5.4), except as altered to reflect the reduction in area or time from the Proposed Action. With implementation of the identified measures, the mitigated effects of the East Pit Alternative on biological resources would be below the level of significance.

4.3.6. Cultural and Paleontological Resources

4.3.6.1. Impacts of the East Pit Alternative

The East Pit Alternative would create approximately nineteen (19) percent less surface disturbance than the Proposed Action within the Project area, and identical surface disturbance within the overbuilt 92 kV/34.5 kV transmission line corridor. The density of cultural resource features determined eligible for the NRHP and identified within the Project mine and process area is substantially higher on the west side, and specifically in the area of the West Pit, than on the east side, in the area of the East Pit and the heap leach pad and process facilities. Thus, the impacts of the East Pit Alternative on cultural resources determined eligible for the NRHP appear to be substantially less than the nineteen (19) percent reduction in surface disturbance from the Proposed Action would imply. Although these impacts of the East Pit Alternative on cultural resources determined eligible for the NRHP are substantially reduced, the remaining effects would remain above the level of significance.

The East Pit Alternative would reduce the adverse effects on the Indian Pass-Running Man ATCC and the Native American trail system through Indian Pass. Nonetheless, remaining impacts would be above the level of significance. The effects of the East Pit Alternative on those cultural resources identified within the overbuilt 92 kV/34.5 kV transmission line corridor would be identical to the Proposed Action, and above the level of significance.

4.3.6.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on cultural resources would be the same as those identified for the Proposed Action (see Section 4.1.6.3). Measures to reduce the significant effects of the East Pit Alternative on cultural resource features identified within the overbuilt 92 kV/34.5 kV transmission line corridor, or within the East Pit Alternative project area, which were determined eligible for the NRHP under criterion "D" would be identical to those identified for the Proposed Action. The mitigated impacts would be reduced below the level of significance. Measures to reduce the significant effects of the East Pit Alternative on cultural resource features determined eligible for the NRHP under criteria "A", "B," or "C" which were identified within the East Pit Alternative project area, or to reduce the significant effects of the East Pit Alternative on the Indian Pass-Running Man ATCC, would be identical to those identified for the Proposed Action. The mitigated effects of these impacts would remain above the level of significance and be unavoidable.

4.3.7. Visual Resources

4.3.7.1. Impacts of the East Pit Alternative

The East Pit Alternative would result in visual contrasts created by changes in line and form from the creation of new structures and facilities, altered surface colors, textures and vegetation cover, and changes in topography similar to the Proposed Action (see Section 4.1.7.2). Because of the slightly smaller area of surface disturbance, the smaller size of the South Waste Rock Stockpile, and the slightly smaller height of the heap, the magnitude of these effects would be slightly reduced from most viewpoints. The view of the East Pit Alternative project mine and process area from KOP #1 and KOP #4 would be very similar to the view of the Proposed Action from these same points (see Figure 4.3 and Figure 4.9, respectively) since the view of the East Pit Alternative from these points is principally of the upper portions of the south ends of the South Waste Rock Stockpile and the heap, which change little from the Proposed Action. The view of the East Pit Alternative project mine and process area from KOP #2 and KOP #3 (see Figure 4.5 and Figure 4.7, respectively) would show the slightly reduced surface disturbance and the elimination of the West Pit, West Pit West diversion channel, and Indian Pass Road from within the East Pit Alternative project mine and process area and ancillary area over the Proposed Action. However, the effects of the East Pit Alternative on line and form would remain, like the Proposed Action, above the level of significance.

Impacts to visual resources from the East Pit Alternative from the lighting of mine and process areas and visibility reduction would remain essentially identical to the Proposed Action (see Section 4.1.7.2), except that they would be shorter in duration by about fourteen (14) years. Like the Proposed Action, the impacts of visibility reduction would be below the level of significance, while the impacts of lighting would be above the level of significance.

4.3.7.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design which eliminate potentially significant effects on visual resources would be the same as those identified for the Proposed Action (see Section 4.1.7.3). Measures to reduce the significant effects of the East Pit Alternative on lighting would also be the same as those measures identified for the Proposed Action. With implementation of the identified measures, the mitigated effects of the East Pit Alternative on visual resources from visibility reduction and lighting would be below the level of significance. The mitigated effects of the East Pit Alternative on visual resources from changes in line and form would remain above the level of significance.

4.3.8. Noise

4.3.8.1. Impacts of the East Pit Alternative

The noise generated by the East Pit Alternative would be essentially identical to the noise generated by the Proposed Action, except that the noise would cease earlier. The impacts of the generated noise on receptors would also be essentially the same as that described for the Proposed Action (see Section 4.1.8.2), except that the impacts would also cease earlier. The noise impacts of the East Pit Alternative would be below the levels of significance.

4.3.8.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects of noise would be the same as those identified for the Proposed Action (see Section 4.1.8.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The noise effects of the East Pit Alternative would remain below the level of significance.

4.3.9. Land Use

4.3.9.1. Impacts of the East Pit Alternative

The compatibility of the East Pit Alternative with existing land uses and adopted land use policies and plans would be essentially identical to that of the Proposed Action (see Section 4.1.9.2). Blasting during mining operations could be a significant potential hazard to low-flying military aircraft using the general area for training exercises (although this impact would end in approximately fourteen (14), rather than twenty (20), years). The East Pit Alternative's impact on recreational use of the area, including wilderness use, would be essentially identical in type, but slightly reduced in scale and duration, from that of the Proposed Action, since the East Pit Alternative would exclude recreational use over 1,276 acres for approximately fourteen (14) years instead of 1,571 acres for approximately twenty (20) years. These impacts would be below the level of significance.

4.3.9.2. Mitigation Measures

Measures to ensure the compatibility of the East Pit Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area would be the same as those measures identified for the Proposed Action (see Section 4.1.9.2). With implementation of the identified measures, the mitigated level of compatibility of the East Pit Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area, would be below the level of significance.

4.3.10. Socioeconomics

4.3.10.1. Impacts of the East Pit Alternative

The East Pit Alternative would have a net beneficial socioeconomic effect which would be reduced from the net beneficial socioeconomic effect of the Proposed Action (see Section 4.1.10.2). These effects would be below the level of significance. Although the number of jobs created under the East Pit Alternative would be approximately the same as the Proposed Action, the length of these jobs would be decreased from approximately twenty (20) years to approximately fourteen (14) years. Initial capital expenditures for (and thus sales taxes paid under) the East Pit Alternative would be approximately the same as the Proposed Action. Recurrent, annual expenditures (such as annual capital expenditures of approximately $1.7 million (and $0.13 million in sales taxes), non-capital expenditures of approximately $26 million, and property taxes of between $200,000 and $600,000) would be reduced by approximately one-third (a) from that of the Proposed Action because of the decreased operating life.

4.3.10.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.3.11. Roads and Public Services

4.3.11.1. Impacts of the East Pit Alternative

The East Pit Alternative would result in an essentially identical increase in traffic as the Proposed Action (see Section 4.1.11.1.2), except that the effects would occur for only fourteen (14), rather than twenty (20), years. These effects would be below the level of significance. The East Pit Alternative would not require the realignment of Indian Pass Road, which would eliminate an impact otherwise judged below the level of significance. The East Pit Alternative would also create the potential for impacts from "spur" roads, which would be below the level of significance.

The East Pit Alternative would have a similar impact on utilities as the Proposed Action. Because of the reduced size of the project, less non-mining waste would be generated (see Section 4.1.11.1.2). All impacts on utilities would be below the level of significance. The East Pit Alternative would also produce impacts on public services similar to the Proposed Action (see Section 4.1.11.3.2). Because of the slightly reduced surface area to be disturbed, there would likely be fewer cadastral monuments which may be destroyed. These impacts would be below the level of significance.

4.3.11.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on roads, utilities and public services would be the same as those measures identified for the Proposed Action (see Section 4.1.11.1.3, Section 4.1.11.2.3, and Section 4.1.11.3.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on roads, utilities and public services would remain below the level of significance.

4.3.12. Emergency Services and Public Safety

4.3.12.1. Impacts of the East Pit Alternative

The East Pit Alternative would have essentially identical impacts on emergency services and public safety as would the Proposed Action (see Section 4.1.12.2), although the life of the East Pit Alternative would be fourteen (14), rather than twenty (20), years. The effects of the East Pit Alternative on emergency services and public safety would be less than significant.

4.3.12.2. Mitigation Measures

Mitigation measures incorporated into the East Pit Alternative design and incorporated by regulation which eliminate potentially significant effects on emergency services and public safety would be the same as those measures identified for the Proposed Action (see Section 4.1.12.3). No other measures would be necessary to reduce impacts of the East Pit Alternative below the level of significance. The effects of the East Pit Alternative on emergency services and public safety would be below the level of significance.

4.3.13. Other Resources

4.3.13.1. Impacts of the East Pit Alternative

The East Pit Alternative would have essentially identical impacts on other resources as would the Proposed Action (see Section 4.1.13), although the life of the East Pit Alternative would be fourteen (14), rather than twenty (20), years. The effects of the East Pit Alternative on other resources would be less than significant.

4.3.13.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.4. Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would result in the complete backfilling of all open pits, at least to original grade, concurrent with final reclamation (see Section 2.2.3). It would consist of first implementing the Proposed Action, then backfilling the East Pit with mined waste rock material, which would be loaded back into haul trucks, driven to the edge of the East Pit, and dumped into the pit until it is full. The Complete Pit Backfill Alternative would use all of the waste rock available to completely backfill all the mined pits, and leave all of the heaped ore on the leach pad.

The Complete Pit Backfill Alternative would not result in any reduction of the surface disturbance compared to the Proposed Action since the Complete Pit Backfill Alternative begins with the implementation of the Proposed Action. However, a substantial amount of the surface area disturbed by waste rock stockpiles and the East Pit would be reclaimed "at grade" because all the material in the waste rock stockpiles would be moved and dumped into the open East Pit. It would take approximately 4.33 years (4 years, 4 months) beyond the end of mining to move enough waste rock back into the East Pit to fill it to grade, although this would likely be accomplished during the twenty (20)-year life of the Proposed Action, while neutralization of the heap and final reclamation were being completed.

4.4.1. Geology and Mineral Resources

4.4.1.1. Impacts of the Complete Pit Backfill Alternative

Except for the complete backfilling of the East Pit, there would be no substantive difference in the impacts of the Complete Pit Backfill Alternative on geology and mineral resources from those identified for the Proposed Action (see Section 4.1.1.2). Under the Complete Pit Backfill Alternative, potential mineral resources exposed at the bottom of the East Pit which are not commercially minable under current economic conditions would be unavailable for subsequent mining without potentially cost-prohibitive removal of the backfilled waste rock. The effects of the Complete Pit Backfill Alternative on geology and mineral resources would be below the level of significance.

4.4.1.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on geology and mineral resources would be the same as those identified for the Proposed Action (see Section 4.1.1.3). No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on geology and mineral resources would remain below the level of significance.

4.4.2. Soil Resources

4.4.2.1. Impacts of the Complete Pit Backfill Alternative

The impacts of the Complete Pit Backfill Alternative on soil resources would be essentially the same as the Proposed Action (see Sectio 4.1.2.2), except that with the complete backfilling of the East Pit with all of the waste rock from the South Waste Rock Stockpile, the potential for erosion within the Project area would decrease slightly. The effects of the Complete Pit Backfill Alternative on soil resources would be below the levels of significance.

4.4.2.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on soil resources would be the same as those identified for the Proposed Action (see Section 4.1.2.3). No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on soil resources would remain below the level of significance.

4.4.3. Hydrologic Resources

4.4.3.1. Impacts of the Complete Pit Backfill Alternative

The effects of the Complete Pit Backfill Alternative on surface and ground water resources would be generally the same as the effects of the Proposed Action (see Section 4.1.3.1.2 and Section 4.1.3.2.2). Any analysis of pit lake potential after mining (as described under the Proposed Action) would be unnecessary. All impacts on hydrologic resources of the Complete Pit Backfill Alternative would be below the level of significance.

4.4.3.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on surface water and ground water resources would be the same as those identified for the Proposed Action (see Section 4.1.3.1.3 and Section 4.1.3.2.3), except that the measures regarding the formation of a pit lake would be unnecessary. No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on surface water and ground water resources would remain below the level of significance.

4.4.4. Air Resources

4.4.4.1. Impacts of the Complete Pit Backfill Alternative

The impacts of the Complete Pit Backfill Alternative on air resources would be essentially identical to the impacts to air resource from the Proposed Action (see Section 4.1.4.2), except that those impacts associated with loading, hauling and dumping would continue after the completion of mining for another approximately 4.33 years as the waste rock was backfilled into the East Pit. The effects of the Complete Pit Backfill Alternative on air resources would be below the level of significance except for PM₁₀. Although the effects of the Complete Pit Backfill Alternative would be below the level of significance, the Complete Pit Backfill Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would remain a cumulatively significant effect.

4.4.4.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on air resources would be the same as those identified for the Proposed Action (see Section 4.1.4.3). No other measures are proposed to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on air resources would remain below the level of significance except for PM₁₀. Although the effects of the Complete Pit Backfill Alternative would be mitigated to below the level of significance, the Complete Pit Backfill Alternative would still contribute to exceedences of the 24-hour CAAQS for PM₁₀ which may continue to occur in the future during periods of high wind. This would remain a cumulatively significant effect.

4.4.5. Biological Resources

4.4.5.1. Impacts of the Complete Pit Backfill Alternative

Vegetation and Plant Habitat

The impacts of the Complete Pit Backfill Alternative on vegetation and plant habitat would be essentially identical to those under the Proposed Action. The same amount of surface disturbance would occur as under the Proposed Action. The time required to complete final reclamation would likely remain the same, and the other impacts to vegetation and plant habitat (from dust, ground water pumping, surface channel diversions, and sensitive plants) would also be essentially identical to those of the Proposed Action (see Section 4.1.5.2), and would remain below the level of significance. The amount of surface area not reclaimed (pit slopes not covered by backfill) would decrease from 165 acres under the Proposed Action to zero (0).

Wildlife, Wildlife Habitat and Wildlife Movement

The amount of wildlife habitat lost under the Complete Pit Backfill Alternative would be the same as that under the Proposed Action. Most of this habitat loss would be temporarily, until the completion of final reclamation (and subsequent vegetation recovery). However, it is likely that a somewhat larger percentage of the disturbed microphyll woodland habitat would be able to be reclaimed within the Project mine and process area as microphyll woodland habitat than the approximately one-half (2) reclaimed under the Proposed Action because more of the land is being reclaimed at approximately natural grade. There would be no open pit slopes which would not be reclaimed, and there would be no open pit area over which wildlife could be killed or injured by falls or from opportunistic. These impacts would be below the level of significance.

The Complete Pit Backfill Alternative would expose wildlife and wildlife habitat to the same impacts from vehicles, hazardous materials, noise, human presence, etc., as the Proposed Action. These effects would be below the level of significance. Other impacts from the Complete Pit Backfill Alternative on wildlife and wildlife habitat (from ground water pumping, surface channel diversions, and sedimentation) would also be essentially identical to those of the Proposed Action (see Section 4.1.5.3). They would also remain below the level of significance.

The impacts of the Complete Pit Backfill Alternative on the desert tortoise would be the same as the Proposed Action, and would be above the level of significance.

4.4.5.2. Mitigation Measures

Measures to reduce the effects of the Complete Pit Backfill Alternative on biological resources would be the same as those measures identified for the Proposed Action (see Section 4.1.5.4), except that the measures to reclaim off-site lands for lands not reclaimed on-site and to backfill the East Pit to prevent the formation of a pit lake are unnecessary. With implementation of the identified measures, the mitigated effects of the Complete Pit Backfill Alternative on biological resources would be below the level of significance.

4.4.6. Cultural and Paleontological Resources

4.4.6.1. Impacts of the Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would result in impacts on cultural resources which are identical to those created by the Proposed Action (see Section 4.1.6.2), except that following backfilling of the East Pit and final reclamation, the visual intrusion into the Indian Pass-Running Man ATCC would be somewhat reduced. The Complete Pit Backfill Alternative would still have a significant adverse impact on cultural resources eligible for the NRHP, and on the Indian Pass-Running Man ATCC.

4.4.6.2. Mitigation Measures

Measures to reduce the significant effects of the Complete Pit Backfill Alternative on cultural resource features identified within the overbuilt 92 kV/34.5 kV transmission line corridor, or within the Project area, which were determined eligible for the NRHP under criterion "D" would be identical to those identified for the Proposed Action. The mitigated impacts would be reduced below the level of significance. Measures to reduce the significant effects of the Complete Pit Backfill Alternative on cultural resource features determined eligible for the NRHP under criteria "A", "B," or "C" which were identified within the Complete Pit Backfill Alternative project area, or to reduce the significant effects of the Complete Pit Backfill Alternative on the Indian Pass-Running Man ATCC, would be identical to those identified for the Proposed Action. The mitigated effects of these impacts would remain above the level of significance and be unavoidable.

4.4.7. Visual Resources

4.4.7.1. Impacts of the Complete Pit Backfill Alternative

The effect of the Complete Pit Backfill Alternative on visual resources from the lighting of mine and process areas and visibility reduction from the emission of dust would be identical to the Proposed Action (see Section 4.1.7.2). These effects would be above the level of significance from mine and process area lighting, and less than significant from visibility reduction.

The visual contrasts of the Complete Pit Backfill Alternative created by changes in line and form from the creation of new structures and facilities, altered surface colors, textures and vegetation cover, and changes in topography would differ in both degree and extent from the Proposed Action because of the backfilling of the East Pit with all of the waste rock from the waste rock stockpiles. When viewed from KOP #1 (Ogilby Road) or from KOP #4 (the informal overnight camping area), the Complete Pit Backfill Alternative would look like the view of the Proposed Action from the same point (see Figure 4.3 and Figure 4.9), except that only the heap would be visible, since the entire South Waste Rock Stockpile would have been removed to backfill the East Pit. The view of the Project mine and process area from KOP #2 (Black Mountain) and from KOP #3 (a hill south of Indian Pass in the Picacho Peak Wilderness Area) following the completion of final reclamation under the Complete Pit Backfill Alternative would differ more from the Proposed Action because of the backfilling of all of the pits and the elimination of all of the waste rock stockpiles (see Figure 4.14 and Figure 4.15). Because the heap would remain as a large alteration in the topography, the effect of the Complete Pit Backfill Alternative on visual resources would be above the level of significance.

4.4.7.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design which eliminate potentially significant effects on visual resources would be the same as those identified for the Proposed Action (see Section 4.1.7.3). Measures to reduce the significant effects of the Complete Pit Backfill Alternative on lighting would also be the same as those measures identified for the Proposed Action. With implementation of the identified measures, the mitigated effects of the Complete Pit Backfill Alternative on visual resources from visibility reduction and lighting would be below the level of significance. The mitigated effects of the Complete Pit Backfill Alternative on visual resources from changes in line and form would remain above the level of significance.

4.4.8. Noise

4.4.8.1. Impacts of the Complete Pit Backfill Alternative

Noise generated by the Complete Pit Backfill Alternative would be essentially identical to the noise generated by the Proposed Action, and the effects of this noise on potential noise receptors would also be essentially identical as for the Proposed Action (see Section 4.1.8.2). However, the Complete Pit Backfill Alternative would also continue the relatively greater noise-producing operations (loading, hauling, and dumping, but not blasting) for approximately 4.33 years longer than the Proposed Action. The impacts of noise from the Complete Pit Backfill Alternative would be below the levels of significance.

4.4.8.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects of noise would be the same as those identified for the Proposed Action (see Section 4.1.8.3). No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The noise effects of the Complete Pit Backfill Alternative would remain below the level of significance.

4.4.9. Land Use

4.4.9.1. Impacts of the Complete Pit Backfill Alternative

The compatibility of the Complete Pit Backfill Alternative with existing land uses and adopted land use policies and plans would be essentially identical to that of the Proposed Action (see Section 4.1.9.2). Blasting during mining operations could be a significant potential hazard to low-flying military aircraft using the general area for training exercises. The Complete Pit Backfill Alternative's impact on recreational use of the area, including wilderness use, would be essentially identical to that of the Proposed Action. These impacts would be below the level of significance.

4.4.9.2. Mitigation Measures

Measures to ensure the compatibility of the Complete Pit Backfill Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area would be the same as those measures identified for the Proposed Action (see Section 4.1.9.2). With implementation of the identified measures, the mitigated level of compatibility of the Complete Pit Backfill Alternative with existing land uses, adopted land use policies and plans, and recreational use of the area, would be below the level of significance.

4.4.10. Socioeconomics

4.4.10.1. Impacts of the Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would have the same beneficial, less-than-significant socioeconomic effects as the Proposed Action (see Section 4.1.10.2). In addition, to complete the backfilling of the East Pit, additional wages, purchases of fuel, replacement equipment and maintenance, and other goods and services would be required, and this would be additional money placed into the economy. These additional costs have been estimated, using a conservative industry average of $0.40 to $0.50 per ton of material loaded, hauled and dumped, at between $80 and $100 million. The level of economic effect would remain less than significant.

4.4.10.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.4.11. Roads and Public Services

4.4.11.1. Impacts of the Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would result in essentially identical increases in traffic and realignment of Indian Pass Road as the Proposed Action (see Section 4.1.11.1.2). The effects would be below the level of significance. The Complete Pit Backfill Alternative would also create the potential for impacts from "spur" roads, which would be below the level of significance.

The Complete Pit Backfill Alternative would have an essentially identical impact on utilities as the Proposed Action (see Section 4.1.11.1.2). All impacts on utilities would be below the level of significance. The Complete Pit Backfill Alternative would also have similar impact on public services as the Proposed Action (see Section 4.1.11.3.2). These impacts would be below the level of significance.

4.4.11.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on roads, utilities and public services would be the same as those measures identified for the Proposed Action (see Section 4.1.11.1.3, Section 4.1.11.2.3, and Section 4.1.11.3.3). No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on roads, utilities and public services would remain below the level of significance.

4.4.12. Emergency Services and Public Safety

4.4.12.1. Impacts of the Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would have similar impacts on emergency services and public safety as the Proposed Action (see Section 4.1.12.2). Because the East Pit would be completely backfilled, the potential public safety concerns from the open East Pit would be eliminated. The effects of the Complete Pit Backfill Alternative on emergency services and public safety would be less than significant.

4.4.12.2. Mitigation Measures

Mitigation measures incorporated into the Complete Pit Backfill Alternative design and incorporated by regulation which eliminate potentially significant effects on emergency services and public safety would be the same as those measures identified for the Proposed Action (see Section 4.1.12.3), except that no measures would be necessary to barricade any open pits. No other measures would be necessary to reduce impacts of the Complete Pit Backfill Alternative below the level of significance. The effects of the Complete Pit Backfill Alternative on emergency services and public safety would be below the level of significance.

4.4.13. Other Resources

4.4.13.1. Impacts of the Complete Pit Backfill Alternative

The Complete Pit Backfill Alternative would have essentially identical impacts on other resources as would the Proposed Action (see Section 4.1.13). The effects of the Complete Pit Backfill Alternative on other resources would be less than significant.

4.4.13.2. Mitigation Measures

No mitigation measures are proposed or recommended.

4.5. No Action Alternative

Under the No Action Alternative, the Proposed Action would not be constructed, and precious metals within the Project mine and process area not be mined under the submitted Plan of Operations. As discussed in Section 2.2.4, if the No Action Alternative is adopted, the Project area would remain as it currently is, and existing dispersed recreational and other uses of the Project area would continue.

4.5.1. Geology and Mineral Resources

No adverse impacts on geology or mineral resources would result from the No Action Alternative, and the identified precious mineral resources would remain in place pending other proposals for development.

4.5.2. Soil Resources

No adverse impacts on soil resources in the Project area would result from implementation of the No Action Alternative.

4.5.3. Hydrologic Resources

No adverse impacts on surface water or ground water resources would result from implementation of the No Action Alternative.

4.5.4. Air Resources

Local exceedences of the CAAQS for PM₁₀ have occured in the past, and may continue in the future, during periods of high winds, even with implementation of the No Action Alternative. This would be a cumulatively significant effect.

4.5.5. Biological Resources

No adverse impacts on biological resources would result from implementation of the No Action Alternative.

4.5.6. Cultural and Paleontological Resources

No adverse impacts on cultural or paleontological resources would result from implementation of the No Action Alternative.

4.5.7. Visual Resources

No adverse impacts on visual resources would result from implementation of the No Action Alternative.

4.5.8. Noise

No adverse noise impacts would result from implementation of the No Action Alternative.

4.5.9. Land Use

The existing land use within, and in the vicinity of, the Project area would likely continue under the No Action Alternative.

4.5.10. Socioeconomics

The No Action Alternative would not create the 120 job opportunities, nor the estimated $7 million in annual payroll, from the Proposed Action. The No Action Alternative would result in the loss of the $48 million initial capital expenditures, $1.7 million annual capital expenditures, and the $26 million per year non-capital expenditures and associated taxes and benefits to the local economy projected by the Project.

4.5.11. Roads and Public Services

No adverse impacts on roads, utilities, or public services from implementation of the No Action Alternative.

4.5.12. Emergency Services and Public Safety

No adverse impacts on emergency services or public safety would result from implementation of the No Action Alternative.

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