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Mining, but no sooner than ten years after initial seeding, an operator can apply for a Phase III final bond <br />release. The operator must demonstrate that all of the revegetation success standards have been met <br />during two consecutive years of the ten year liability period. In addition, the Division must verify that all <br />required reclamation steps have been successfully accomplished. With final approval of the Phase II <br />release, all bond monies can be returned to the operator and the jurisdiction of the Colorado Division of <br />Reclamation, Mining and Safety over the mine site is terminated. <br />Except for the woody plant density standard, the remaining revegetation success standards for the <br />grassland community and for the riparian community are the same. The success standard for cover is 90% <br />of the total herbaceous cover sampled within the designated reference area. The same success standard <br />applies to production. The woody plant density standard is 90% of 100 stems/acre for the grassland <br />community and 90% of 1,000 stems/acre for the riparian community. Species composition success was <br />measured by number of species and percent relative cover for cool-season grasses, percent of relative <br />cover for perennial forbs and number of species for woody plant diversity. <br />The data from the 2006 Revegetation Success Evaluation Report and the 2006 & 2007 Revegetation <br />Success Evaluation Report show that all of the revegetation success standards were exceeded or <br />substantially exceeded at the Blue Ribbon Mine reclaimed areas. The sampling protocol and statistical <br />methodology required under Rule 4.15. 11 were used in the revegetation success analyses. <br />Cover and production success was demonstrated for both revegetated communities (grassland and <br />riparian) in both years. Sample adequacy was demonstrated for each community and each parameter, in <br />both reclaimed and reference areas (as such, demonstration of success was by direct comparison of the <br />reclaimed area sample mean to the reference area standard; westing was not required to demonstrate <br />success). Diversity success was properly demonstrated for each community, both years. <br />Woody plant density success was properly demonstrated for the riparian area each year, based on direct <br />comparison of the reclaimed area sample mean (from a statistically adequate sample) to the approved <br />standard. As with cover and production, there was no need for hypothesis testing; reclaimed area sample <br />mean exceeded the approved standard by a very wide margin in both years. (The Division noted that, in <br />the 2006 Revegetation Success Evaluation Report, a sample adequacy formula that is more stringent than <br />required by current regulation was initially employed, with the resulting conclusion that sample adequacy <br />was not achieved. The 2006 & 2007 Revegetation Success Evaluation Report employs the correct <br />formula as specified in Rule 4.15.11, with the result that a statistically adequate sample was obtained both <br />years). <br />For the grassland community, the approved plan allows for woody plant density success to be <br />demonstrated using a complete census count, as an alternative to sampling, using a well defined protocol <br />to ensure an accurate count. The census method used was approved before the current regulations <br />became effective, and the method is more stringent than sampling methods specified in the regulations; <br />any error in counting is more likely to result in "under-count" than "over-count". Year 2006 census <br />results in the grassland community indicated 258 woody stems per acre, and Year 2007 census indicated <br />268 woody stems per acre, compared to the success standard of 90 stems per acre. Although the <br />regulations do not specifically address the total census method, as applied in this case it is actually more <br />precise than sampling, the Division accepts the census as a valid demonstration of success for the small <br />grassland area woody stem density standard. <br />The data from both consecutive sampling years demonstrates that the revegetation efforts successfully <br />support the postmining lands uses of wildlife habitat, grazing and recreation.