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Section 2.04.10 area corresponds to an existing powerline road as shown on the Regional Vegetation Map, (Map 2.04- • MS). Mapping covered much of the present Permit azea, while sampling was limited to a zone of undisturbed vegetation surrounding the disturbance areas existing at the time of sampling. Mapping involved the use of color infrared and black and white photos to identify and delineate vegetation types at a scale of 1" = 500' based on vegetation structure and dominant species, with subsequent field reconnaissance to verify or adjust the mapped vegetation community boundazies. Vegetation mapping information is presented on the Regional Vegetation Map, (Map 2.04-M8). Due to similarities in elevation, aspect, and surrounding undisturbed vegetation and the very limited amount of new surface disturbance, the vegetation information provided by the Baseline Vegetation Inventory is considered to be representative for both existing and proposed mine surface disturbance activities. Vegetation sampling included measurement of cover, production, and woody plant density in July and August of 1981 and calculation of diversity from the cover data. Cover and shrub and tree density data were collected rising randomly located 50-meter transects, with cover measurements at one-meter intervals along each transect using an optical sight, shrub counts within the area defined by the transect length and a 0.5-meter width (]-meter total width) on each side of the transect line, and tree density counts within the area defined by the transect length and a 2.5-meter width (5-meter total width) on each side of the transect line. Randomly located production plots were used to determine production for the two dominant vegetation types identified. Rectangular 1-meter x 4-meter plots were used Eor the Juniper Woodland type and 1-meter x 2-meter plots for the Mountain Shrubland type with clipping of the current year's growth and sorting by species for grasses and b}' type For forbs. Sample adequacy was evaluated using the equation For aone-tailed t-test: with an 80 percent confidence interval and a 10 percent detection limit: Where Nm;,, is the minimum number of transects sz is the sample variance tz is the statistical confidence interval (one-tailed w/80 percent confidence) d is the desired detection limit (10 percent) x is the mean sample value Species diversity was calculated for each vegetation community from the cover data using the formula (Whittaker, 1975): -£ (n;/N) log (n;/I~ Where n; is the absolute value of cover for each species N is the absolute value of total cover for all species Species identification was based on standard taxonomic references for Colorado (Weber and Johnston, 1979; Nickerson et al., 1976; Beetle, 1970; and Thornton et al., 1974) with confirmation by Dr. William Weber, Colorado State University. Given the dominance and consis[ency of the sampled vegetation communities for the limited mine surface disturbance areas, subsequent sampling of other surface disturbance areas was not deemed necessary by the DMG. Limited delineation and mapping of potential riparian vegetation and wetlands areas in the vicinity of the Elk Creek Mine surface facilities was conducted by Cedar Creek Associates 1999 in conjunction with the North Fork Coa] leasing EIS. This field im~estigation • resulted in delineation of very limited areas of riparian/wetlands vegetation within and in a narrow band immediately adjacent to the Elk Creek channel. Cedar Creek Associates completed similar delineations for the II West Coal Refuse Disposal Area in early 2003, and found no riparian or wetland vegetation. Refer to Exhibits 2.04-E4, Ht~drolog}' Information, and 2.04.EG, Vegetation ]nformation, for additional details. TR-43 2.04-103 Revised August 2003