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Phase II bond release vegetation establishment success requires that the operator establish vegetation <br />~ that supports the approved post-mining land use and which meets the approved success standard for <br />cover. Based on Rule 4.15.8 and the approved Colowyo permit, the approved cover standard is 90% of <br />the weighted reference azea cover, with a 90% level of confidence. Colowyo measured the herbaceous <br />vegetative cover on reclaimed azeas in the East pit, West Pit, and Section 16 Pit, Mountain Shrub <br />reference area, and Sagebrush Reference azea, in July 2000. Colowyo uses a weighted reference azea <br />concept, as described by Rule 4.15.7(4)(b). <br />Reclaimed areas requested for Phase II bond release were reclaimed and seeded between 1986 and 1995. <br />Total herbaceous cover measure on the reclaimed area in 2000 was 75.7%. Herbaceous cover measured <br />on the Mountain Shrub Reference azea was 72.8% and the Sagebrush reference area was 57.4%. The <br />weighted mean of both reference areas was 65.89%. Ninety percent of the weighted mean calculates to <br />59.3%. The herbaceous cover on the reclaimed area exceeds the weighted mean cover for the reference <br />areas. The Division finds the reclaimed area successful for vegetation establishment for phase 11 bond <br />release purposes. Data met sample adequacy requirements. <br />Although not a requirement for Phase II bond release, the Division reviews the vegetation sample data to <br />assess how the reclaimed community is progressing towazd final reclamation standazds for species <br />diversity. On the reclaimed azea ten species exceeded the minimum 3% relative cover. No one species <br />exceeded 50% relative cover. The most abundant species measured was Intermediate wheatgrass <br />(Agropyron rntermedrum) measured at 24.1 % relative cover, followed by Kentucky bluegrass (Poa <br />pra[ensis) with 16.1 % relative cover. A third cool season grass, Thickspike wheatgrass (Agropyron <br />dosystachy:im), measured 10% relative cover. Cicer milkvetch (Astragalus titer) met the requirement <br />•~ for the establishment of a minimum of one forb species with a relative cover of 8.1%. Only one of these <br />4 species is considered a native species. All four species were in the approved seed mix at the time the <br />site was reclaimed. The Division finds that the reclaimed area meets the diversity standazd. <br />Conclusion: <br />Colowyo has met the Phase II reclamation standards for topsoil replacement and vegetation <br />establishment on the azea requested for phase II bond release. Vegetative species diversity is successful <br />for the azea sampled for this bond release application. <br />M:/coal/jhb/C81019 SL03.doc <br /> <br />