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2.2.3 Total Herbaceous Production <br />Total herbaceous production was estimated by the harvest method. One herbaceous <br />production plot was located and randomly oriented at the origin of each cover transect. <br />Herbaceous production plots were 0.50 meter2 in area. All current year above ground live <br />herbaceous plant biomass was clipped within the 0.50 meter2 quadrat. Production material <br />was air dried until weights varied by no more than 0.1 g. <br />2.2.4 Species Composition <br />Species composition information was derived from quantitative vegetation cover data. <br />Relative cover information provided a basis for evaluation of the importance of each <br />encountered plant species and lifeform and for comparison to the final revegetation success <br />criterion. The table presenting data summaries for total vegetation cover for each area <br />sampled also contains the relative cover by species and a column depicting the numerical <br />ranking of each species by relative cover within the area. <br />2.3 SAMPLE NUMBERS/SAMPLE ADEQUACY <br />For the purposes of this study, total vegetation cover and total herbaceous production <br />sampling were undertaken to sample adequacy with a minimum of fifteen (15) samples. <br />Parameter testing occurred at the one-sided 90% confidence level. Comparisons between <br />sample mean parameter values and the revegetation success standard assume that the sample <br />mean value accurately represents the population mean in all cases. <br />The following formula was used for sample adequacy calculations: <br />(t)2 (s)2 <br />nmin_ ---------------- <br />(d Xbar)2 <br />where: nmin = minimum sample size <br />s = sample standard deviation <br />t = the Student's t distribution value at the 90% level (one-sided) <br />d = percent acceptable deviation from the mean (10%) <br />Xbar = sample mean <br />2.4 STATISTICAL ANALYSIS <br />Statistical analysis for the revegetation success criteria of total vegetation cover and total <br />herbaceous production is required if the value of the sample mean from the reclaimed area is <br />less than 90 percent of the value of the final revegetation success criterion for total vegetation <br />cover or total herbaceous production. The 2014 reclaimed area sample means for total <br />vegetation cover and total herbaceous production were greater than the corresponding <br />revegetation success criteria; therefore no statistical analysis was required. A statistical <br />analysis is not required for the evaluation of species composition. <br />Mountain Coal Company, LLC West Elk Mine Page 5 <br />2014 Vegetation Report: Phase III Bond Release Eligible Areas <br />