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criteria for the site be met in at least the last two consecutive years of the extended (ten <br />year) liability period. <br />Cover: <br />The approved cover standard for the mine requires that "Vegetative cover will be <br />restored on the reclaimed area to at least 90% of the vegetative cover as that on the <br />approved reference azea." <br />Based on review of the data collected in year nine (1998), the cover standard was <br />achieved. The permittee chose to analyze the vegetative cover data eliminating the <br />annual and biennial species component from both the reference area data and the <br />reclaimed area data. This method is acceptable and is suggested in the Division's <br />"Guideline Regarding Selected Con! Mine Bond Release /ssaes", dated Apri] 18, 1995. <br />Reference area vegetative cover collected in June 1998 was 25.07 %. Ninety percent of <br />the reference azea cover is 22.56%. The reclaimed area cover measured 23.44% during <br />the June 1998 data collection. The pemtittee successfully demonstrated that the <br />reclaimed area cover is greater than 90% of the reference area cover with a 90% <br />confidence interval. <br />The cover standard was again achieved for the 1999 (year ten) based on review of the <br />data collected. As done with the 1998 data, the permittee analyzed the vegetative cover <br />data by eliminating the annual and biennial species component from both the reference <br />area data and the reclaimed area data. Vegetation cover data were collected in July 1999 <br />on both the reference area and reclaimed area. The reference area vegetative cover for <br />1999 was 21.87 %. The reclaimed area cover measured 24.67 %. The permittee <br />successfully demonstrated that the reclaimed area cover was greater than 90% of the <br />reference area cover for the last two years of the liability period. No additional statistical <br />evaluation was necessary. <br />rtnd~env;fy: <br />The approved productivity standard for the mine requires that herbaceous productivity be <br />restored to at least 90%o of the production of the approved reference area. <br />Herbaceous productivity measured on the reference area was 238 lbs./acre in 1998 (year <br />nine) and 199 lbs./acre in 1999 (year ten). <br />Productivity data on the reclaimed areas was highly variable. Kaiser was not able to <br />achieve sampling adequacy after collection of 50 production quadrats for both 1998 and <br />1999 data. Kaiser analyzed the productivity data using non-parametric statistical <br />methods. The analysis methodology is acceptable to the Division. These data collected <br />on the reclaimed area in 1998 have anon-normal distribution, as do the 1999 data. <br />Using non-parametric statistical analyses, the operator determined that the median of the <br />6 <br />