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Quantitative density data from fifty three randomly located samples within the mapped woody plant <br />concentration areas were gathered in 2012 from belt transects located and oriented randomly. In the <br />Background woody plant density portions of BRB PSCM -2, fifty -three sample points were located and <br />sampled for woody plant density in conjunction with cover and/or production. The belt transects (i.e. <br />elongate sample plots) were 2 m x 50 m in dimension and randomly oriented from the origin. Within each <br />belt 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 PSCM -2 <br />was determined as follows: <br />(St) <br />nmm <br />(dx) <br />Where: <br />n,„,,, = number of sample points needed in a given vegetation type to be capable of <br />detecting a 15% reduction in the mean with 90% confidence; <br />s = standard deviation (n -1); <br />t = t statistic (one - tailed, 90% confidence; n -1 degrees of freedom; if n >30, <br />t = 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 />Were sample adequacy not achieved using the above formula, then the reverse null non - parametric <br />approach set forth in CDRMS rules (4.15.11(3)(a)) would be used as follows: <br />1 <br />L = p(n + 1) — Z Enp (1 p)�� <br />Where: <br />L= order statistic corresponding to the one sided lower 80% confidence limit <br />p = 0.5 (e.g. the 0.5 quantile, or median) <br />n = sample size <br />Z = 0.842 (the t -table value for infinite degrees of freedom for 1 sided test; alpha = 0.20) <br />If the lower 80% confidence limit is greater than 70% of the shrub concentration standard of 2000 stems <br />per acre (1400), reclamation success for concentration area woody plant density for Phase III in BRB <br />PSCM -2 2012 would be demonstrated. <br />Climatic 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 />10 <br />