2016-12-23_PERMIT FILE - C1982056A (8)

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It is separated from the access road by over 0.5 mil (0.8 km) and from the Fish Creek Borehole /Shaft Area by approximately 0.75 mi (1.2 km). The access road and most of the Fish Creek Borehole /Shaft area are, however, shielded by topography from direct line of sight of the Twentymile Lek by topography. Early morning shift traffic (7:00 am) on the access road will not coincide with the timing of peak breeding activity of sage grouse (one hour before sunrise to one hour after sunrise, Rodgers 1964, Gill 1965, Jenni and Harzler 1978). In addition, the Fish Creek Borehole /Shaft: Area will only be a ventilation shaft with limited employee activity once construction is complete. Therefore, mine activities are not expected to affect grouse breeding activity at the Twentymile Lek. Possible mitigative measures to further limit the potential for disturbance of grouse leks are listed in the response to Rule 2.05.6(2). Map 21, Locations of Sandhill Crane Nests and Nesting Habitat and Raptor Cliff- nesting Habitat, shows the locations of sandhill crane nest sites and potential crane nesting habitat in relation to the proposed surface facilities. Sandhill cranes are sensitive to human disturbance, particularly during the nesting and incubation period (May through June 30). Enriquez (1979) considered lack of human disturbance a key limiting factor in sandhill crane use of suitable nesting habitat. However, cranes foraging in Twentymile Park appear to adapt to human activity rather rapidly (Grant 1983). Blake (1974) recommended that permanent major developments and roads should be at least 0.25 and 0.125 mi (0.4 and 0.2 km), respectively from crane nesting areas. To insure that nest sites will continue to be suitable for use by nesting cranes, any major developments are planned to be located at least 0.25 mi (0.4 km) away from nest sites. In addition, all access roads are planned to be located at least 0.125 miles (0.2 Km) from potentially suitable nesting habitat. Possible methods to limit disturbance to sandhill crane nesting habitat are listed in the response to Rule 2.05.6(2). Subsidence resulting from the proposed underground mining will have very little or no impact on most wildlife species and their habitats. The one possible exception is the potential for portions of the Twentymile Sandstone cliffs to become unstable, which could result in some rock falls or toppling. These cliffs serve as nesting habitat for raptors. As shown on Map 23, approximately 5,000 -6,000 feet of these cliffs will be undermined along Routt County Road 27. Raptor nesting surveys completed by the USFWS in the early 1980's show a number of nests in •the area to be undermined. The 1982 USFWS survey shows two inactive Golden Eagle nests, three inactive buteo nests, and two active Red- tailed Hawk nests in the area to be undermined. The surveys also revealed an active Red - tailed Hawk nest and the same active Prairie Falcon aerie to the northeast of the proposed mine area. The above - referenced surveys, plus field observations by TCC personnel over the past ten years, reveal that the Golden Eagle aeries have remained inactive. The Redtail Hawks have continued to nest in the area, but use a number of alternate nest sites. The Prairie Falcon aerie has remained active, and is well outside the area to be subsided. As agreed with USFWS, there is little potential for permanent impacts to the Red - tailed Hawks because of the number of alternate nest sites. Under the agreement, however, TCC will conduct nesting surveys prior to mining under the cliffs, if mining is to occur during any nesting season (February to July). If an active raptor nest is identified for a species of interest, then the USFWS will be contacted so that a "take" permit can be obtained to remove or prevent access to the nest during the period of subsidence. No significant impacts to wildlife are expected as a result of subsidence. Some subsidence will occur under Fish Creek in Twentymile Park, however, it will be predictable and should not cause any resultant changes in vegetational communities, with the possible exception that small areas of upland vegetation adjacent to active stream channels may be converted to transitional riparian communities due to increased moisture. Monitoring of subsidence will be conducted as described in the response to Rule 2.05.6(6). Wildlife Information for Additional Disturbance Areas and Activities EMD (Panel 2 -Right through 6- Right, PR97 -04) - The Colorado Division of Wildlife was contacted to determine •if any raptors could be nesting in the sandstone outcrop along Routt County Road 27, or in the sandstone outcrop areas along Middle Creek. The result of the inquiry is presented in Exhibit 19A, Raptor Survey, Eastern Mining District. All of the nest sites, whether they are inactive, active, or occupied alternate nest sites, are located in Sections 33 and 34, Township 5 North, Range RN08 -05 2.04 -78 03/12/10