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The location of woody plant concentration areas in the BRB -1 were documented by field mapping and <br />assisted by aerial photography (Routt County DOQQ 2009). During the mapping, "High" density was <br />reserved for those areas apparently (visually) greater than or equal to 2000 shrubs per acre (one quarter <br />shrub per sq.m.; 25 shrubs per 100 sq.m.). All other portions of the BRB -1 were labeled as "Background" <br />density. <br />Quantitative density data from 53 randomly located samples within the mapped woody plant <br />concentration areas were gathered from belt transects located and oriented randomly. In the background <br />woody plant density portions of BRB -1, 53 sample points, in conjunction with cover and /or production (up <br />to 35 samples), were located and sampled for woody plant density. The belt transects (i.e. elongate <br />sample plots) were 2 m x 50 m in dimension and randomly oriented from the origin. Within each belt <br />transect, all living trees and full shrubs whose root crowns emerge within the plot boundaries were <br />counted by species. Sample adequacy of the collected woody plant density data from the BRB -1 was <br />determined as follows: <br />nmin = <br />(st) <br />(dx) <br />Climatic Data <br />Where: <br />n min = the number of sample points needed in a given vegetation type to be capable <br />of detecting a 15% reduction in the mean with 90% confidence; <br />s = standard deviation (n -1); <br />t = the t statistic (one - tailed, 90% confidence; n -1 degrees of freedom; if n >30, t = <br />1.282 for purposes of this study); <br />d = acceptable amount of inherent variability to be identified between the sample <br />mean and the true population mean (0.15 for purposes of this analysis); <br />x = sample mean for woody plant density data. <br />Seneca Coal Company (SCC) has historically provided precipitation data for the Seneca II (and PSCM) <br />and IIW Mines, however 2012 data was not available as of December 2012, and therefore 2012 <br />precipitation data were obtained from the NOAA administered Western Regional Climate Center (WRCC) <br />for the nearby town of Hayden (Station 053867). Since the long -term average for the Seneca IIW mine <br />exists for only 26 years, the long -term average monthly precipitation data from Hayden (Station 053867) <br />was used as an appropriate base for comparison. Temperature data from the Hayden station was used <br />as well. <br />11 <br />