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TWC has surveyed the expanded area ten times: December 1994, each January from 1995 through 1998, each February from 1999 through 2002, and March of 2003. Elk densities in the expanded area ranged from 1.9 to 16.5 elk/mi2 during 1994-2003. With the exception of four years (1994, 1996, 1998, and 2003), elk densities in the expanded area have remained relatively constant, ranging between 7.3 to 8.8 elk/mi2 (Figure 1). The low density recorded during the December 1994 survey was likely due to poor ground conditions (patchy snow cover) and the use of a fixed-wing aircraft for the survey. These factors likely affected the observers' ability to detect animals and resulted in under counting. Considerably more elk were observed a month later, January 1995, when the area was surveyed from a helicopter. The high elk densities observed in 1996 and 2003 were likely influenced by excessive snowpack during those years in the higher elevations of the Williams Fork Mountains. The deep snow likely pushed the ungulates out of the higher elevations and north into the survey area where reduced snow depths made walking easier and forage more accessible. The elevated density observed in January 1998 of 14.2 elk/miZ could not be explained b}~ snow depth, as snowfall was minimal during winter 1997-1998. • Herds were widely distributed over the expanded area during each of the ten surveys. However, herds were always conspicuously absent from the agricultural fields and grasslands in the northwest, north-central, and southeast parts of the area. Because there were no tall grasses or shrubs in those habitats, the vegetation was typically covered by snow during winter. Consequently, there was little readily available winter forage for big game in those portions of the survey azea. A total of 30 mule deer in six herds were observed within the expanded survey area in 2003. Mule deer herds ranged in size from 1 to I S animals, and averaged 5 individuals. Mule deer were only observed on three portions of expanded area (Exhibit 1), and typically within mountain brush habitats. Over the 10 years of big game surveys, mule deer densities in the expanded area have been relatively low and ranged from 0 to 0.75 deer/mil (Figure 2). The lack of deer observations during the December 1994 survey was likely due to poor ground conditions (patchy snow cover) and the use of a fixed-wing aircraft for the survey. During aerial surveys, most mule deer have typically been seen in three distinct portions of the survey azea: the northwest (north and west of Seneca II-W), extreme northeast, and • 2003 Seneca II Mine Wildlife Monitoring Page 5