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IV. DISCUSSION AND CONCLUSIONS <br />Two reclaimed and revegetated azeas (Area 1 and Area 2) were quantitatively sampled <br />to evaluate revegetation establishment in light of Phase II bond release requirements. <br />The Upland Sagebrush Reference Area was also quantitatively sampled to provide the <br />basis for a vegetation cover standard for those reclaimed areas governed by the <br />requirements of Rule 4.15.8. Statistical evaluations were undertaken as necessary to <br />evaluate the equivalency of the reclaimed areas to the reference area or other applicable <br />standard. <br />COVER <br />AREA 1 <br />Area 1 meets the revegetation success cover requirements for Phase II bond release. <br />Area 1 subazeas which are governed by the requirements of 4.15.8, were equal to or <br />greater than 90% of the cover value obtained from the reference area with 90% <br />statistical confidence. Area 1 subareas which aze governed by the requirements of <br />4.15.10, were equal to or greater than 90% of the cover value standard (live vegetation <br />cover plus litter) set by CDMG with 90% statistical confidence. <br />AREA 2 <br />Area 2 meets the revegetation success cover requirements for Phase II bond release. <br />Area 2 revegetation success is governed by the requirements of 4.15.8. Area 2 <br />vegetation wver was equal to or greater than 90% of the cover value obtained from the <br />reference azea with 90% statistical confidence. <br />SPECIES COMPOSITION <br />A standard has been set by CDMG for the evaluation of species composition at the <br />' New Horizon Mine 1. To be judged successful, at fatal bond release, this standard <br />requires that three grasses, one fort, and one shrub be established with relative cover <br />values greater than three percent. The combined relative importance of the qualifying <br />I species will not exceed 85 percent, and no one species will contribute greater than 40 <br />percent relative importance (CDMG, 1991). Seasonal variety requirements were <br />waived for the New Horizon Mine 1 Area. <br />The Colorado Division of Minerals and Geology considers species composition of the <br />revegetated and reclaimed areas to be an indicator of successful vegetation <br />establishment. For Phase II bond release, revegetated areas should show a trend <br />toward achievement of the applicable species diversity standard. Species composition <br />data at the Phase II bond release stage should illustrate a trend in vegetation community <br />development toward the stable, self-perpetuating vegetation community desired on a <br />given post-mining landscape. <br />17 <br />