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Tables 3 and 4 of the Appendix present the sampled data regarding <br />absolute cover. The great majority (96.80/,,) of the overall cover is contributed by <br />perennial, non-noxious species. Annual, biennial, and noxious species only sum to <br />1.9% absolute cover. Six species (all cool-season grasses) individually contributed <br />more than 4% absolute cover: ELIN (Elytrigia interme&a), POPR (Poa <br />pratensis), LECI (Leymus cinerezrs), BRIN (Bromopsis inermis), PASM <br />(Pascopyrum smithii), and ELREP (Elytrigia repens). <br />As Table 12 indicates, the cover standard for the Meeker Area mine is <br />63.86%. The actual comparison value, 90% of that standard (Rule 4.15.8(3)(a)), <br />is 57.5%. The operator must demonstrate that the reclaimed cover is "...not less <br />than 90 percent of the cover as determined from the reference area or approved <br />standard with 90 percent statistical confidence,..." Twenty-eight cover samples <br />spread over the mine's 22.3 acres of reclaimed surface resulted in an estimated <br />absolute vegetative cover of 57.9%, exceeding the 90% comparison value. <br />However, 1.9% absolute cover was contributed by annual, biennial, or non- <br />noxious plant species. The non-noxious, perennial absolute cover is 56.1% which <br />does not exceed the 90% comparison value. Because 56.1% is a sampled value, a <br />one-sample t-test was carried out to determine if that value, while lower than the <br />90% comparison value, was lower with 90% statistical certainty. As per page 22 <br />of the CDMG Bond Release Guidelines, the null hypothesis was tested that 56.1% <br />was greater than or equal to 90% of the standard. Table 11 of the Appendix <br />presents a more detailed account of the actual statistical comparison. The result <br />was that the null hypothesis that the reclaimed area cover is greater than or equal