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that have historically been of concern and continue to be the focus of control efforts on the Peabody <br />Sage Creek Mine site include Canada thistle (Breea arvensis), houndstongue (Cynoglossum officinale), <br />and whitetop (Cardaria draba). The operator's weed management program has been successful in <br />reducing the densities of these species and minimizing expansions of populations. No noxious or <br />invasive weed infestations or patches of weeds were observed during the inspection. <br />Reve2etation Success <br />All areas requested for Phase III bond release per SL -03 have previously received Phase I and II bond <br />release. Previous Phase I and II bond releases for the requested bond release blocks were approved <br />with SL -01, SL -03, and SL -04 associated with the Seneca II Mine (C -1980 -005). Reclamation <br />parcels were reclaimed between 1989 and 2012. Vegetation sampling was conducted during 2011 <br />and 2012. All parcels have met the minimum liability period as required by rule 3.02.3(2)(b). The <br />approved post- mining land use is rangeland and wildlife habitat. <br />PSCM has implemented an annual grazing plan on reclaimed lands at the Peabody Sage Creek Mine <br />since 1987. PSCM's grazing plan takes into account the available forage biomass. PSCM stocks <br />livestock at an appropriate capacity to leave no less than 50% of the available forage biomass. <br />Grazing was conducted annually between mid -July through mid - September. <br />PSCM uses an acreage weighted value for vegetative cover and herbaceous productivity success <br />determination based upon sampling of two main vegetation type reference areas. The two reference <br />areas are the Mountain Shrub reference area and the Sagebrush reference area. Based upon the pre - <br />mining vegetation community distribution, the mountain shrub community composed approximately <br />83% of the mining area, while the sagebrush community contributed approximately 17% of the area. <br />Cover <br />Reclamation success for vegetative cover requires a summation of the weighted average vegetative <br />cover of the two reference areas multiplied by a factor of two. The allowable vegetative cover of the <br />reclaimed Bond Release Block, BRB, shall equal or exceed 90 percent of this calculated value. <br />Weighted values of the two reference areas are based on the percentage of the pre- disturbance <br />acreage composed of each vegetation community. The mean allowable vegetative cover of the <br />Sagebrush reference area is multiplied by 17 %, while the mean allowable vegetative cover of the <br />mountain brush reference area is multiplied by 83 %. These two values are added together and then <br />multiplied by a factor of two. <br />PSCM collects "all hit" vegetation data, but uses "first hit" data for reclamation success <br />determination. All hit vegetation data did achieve sample adequacy. However, conversion to "first <br />hit" cover resulted in the "first hit" vegetation data not meeting the adequacy calculations. The <br />Division accepts PSCM's sampling methodology. <br />Sample adequacy was achieved for vegetative cover for the 2010 and 2011 sampling of the BRB and <br />sagebrush reference area. Due to a high variance in the vegetation sampling results, PSCM was <br />unable to achieve sample adequacy for the 2010 and 2011 cover sampling of the mountain brush <br />