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1998 reclaimed area production data (4201bs./acre) exceeded the mean of the 1998 <br />reference area production (238 lbs./acre). The operator calculated the lower limit of the <br />90% confidence interval and still found the reclaimed area production exceeded that of <br />the reference area. The method used to estimate the lower confidence interval is found <br />in Statistical Methods for Environmental Pollution Monitoring by Richard O. Gilbert <br />1987. This method is recommended by the Division and acceptable for analyses of non- <br />normal sets of data. <br />The operator used non-parametric statistical analyses and found that the median of the <br />1999 reclaimed area production data (619 lbs./acre) exceeded the mean of the 1999 <br />reference area production data (199 lbs./acre). The operator calculated the lower limit <br />of the 90% confidence interval and again found the reclaimed area production exceeded <br />that of the reference area. <br />Diversity: <br />The diversity success standard for this site requires establishment of a vegetative <br />community that has all of the following characteristics: <br />^ A minimum of two perennial cool season grasses with each contributing a minimum <br />of 3% relative cover and no individual species exceeding a maximum of 40% <br />relative cover <br />^ A minimum of two perennial non-noxious forbs with each contributing a minimum <br />of 3% relative cover and no individual species exceeding a maximum of 40% <br />relative cover <br />^ Any combination of perennial warm-season grasses with at least 6% relative cover <br />and no upper limit <br />The diversity standard was achieved on the reclaimed site in 1998 (year nine). Five <br />perennial cool season grasses were measured that met the standard. The two most <br />dominant cool season species were Russian wildrye (27% relative cover) and Slender <br />wheatgrass (10.58% relative cover). Two perennial forbs providing greater than 3% <br />cover were measured on the reclaimed area. The two perennial forb species were Alfalfa <br />at 3.75% relative cover and Winterfat with 3.37% relative cover. Winterfat is classified <br />as asub-shrub, which is a species that dies back to a root crown every year. This <br />function is similar to a perennial forb. The Division allows for a forage species like <br />Winterfat to count towards a perennial forb success standard since it fulfills a similar <br />role in the vegetative community. Three warm season perennial grasses were measured, <br />Blue grama (13.8%), Side oats grama (6.9%), and Sand dropseed (1.6%), for a total <br />warm season component of 22.3% relative cover. The 1998 diversity measurements <br />were collected in September 1998 to assure proper identification of the species, while <br />the cover and production data for 1998 were collected in June 1998. <br />The diversity standard was achieved on the reclaimed site in 1999(year ten). Five <br />perennial cool season grasses were measured that met the standard. The two most <br />dominant cool season species were Russian wildrye (20.5% relative cover) and Slender <br />wheatgrass (20.0% relative cover). Two perennial forbs were measured on the reclaimed <br />area at greater than 3% cover. The two perennial forb species were Alfalfa at 5.41% <br />7 <br />