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by mining in the Southeast portion of the New Horizon 1 Mine (generally this was the N <br />1/2 NE 1/4 Section 36 T47N R16W and the SW 1/4 NW 1/4 Section 31 T47N R15W). <br />10.2 Production <br />This section has not changed from the earlier approved permit. A technical standard as <br />opposed to use of the reference area is proposed for the revegetation success standard <br />for production. This standard is to be based on the potential productivity of the dominant <br />soils present on the New Horizon 1 Mine permit area. Potential productivity values have <br />been determined by the Soil Conservation Service (SCS) and are included in the soil <br />survey of Western Montrose and San Miguel Counties presently being published. The <br />more detailed Nucla Mine Soil Survey identified the Shavano and Persayo soils as the <br />most prevalent and information on potential productivity from the SCS survey was <br />correlated with these soils. The potential productivity of the Shavano and Persayo series <br />was taken from the most recent Soil Survey Interpretation Sheets (SCS Form 5) from the <br />SCS soil survey noted above. The Shavano series occupies approximately 73 percent <br />of the affected area and has a potential production in favorable years of 500 Ibs /acre. <br />The Persayo series occupies the remaining 27 percent and has a potential production in <br />normal years of 250 Ibs /acre. <br />The production standard for reclaimed areas is as follows: All dryland pasture areas and <br />the rangeland areas receiving ten (10) inches of topsoil will have acceptable herbaceous <br />production when the production value determined for the reclaimed areas is not less than <br />90 percent of 500 Ibs /acre with 90 percent statistical confidence. The 500 Ibs /acre value <br />is to be used for these areas because Shavano soils will provide the majority of the <br />replaced topsoil. This standard applies to Vegetation Sampling Area 2. The remaining <br />reclaimed areas excluding any yet to be reclaimed pre -law areas or areas previously <br />mined and re- affected by current operations as specified in 4.15.10) will be compared to <br />the potential productivity for the Persayo soils at 250 Ibs /acre with 90 percent statistical <br />confidence. As of the mid term review of 2006, areas 9 -A and 9 -B have been released. <br />Vegetation Sampling Area 2 has not met the standard. <br />As specified in 4.95.90, previously mined areas re- affected by current mining operations <br />need not be evaluated for production. Therefore, Vegetation Sampling Areas 9 -A and 9 -B <br />will not have production standards. <br />Vegetation Sampling Area 3 is the small area of alfalfa irrigated hay. This area has a <br />standard of 90% of 2710 Ibs /acre, which was derived from the production information of <br />Table 22 -3. <br />Map 22 -1 "Postmine Vegetation Map -New Horizon 1 Mine" illustrates the areas reclaimed <br />as dryland pasture, as rangeland receiving ten (10) inches of topsoil, and as other <br />reclaimed rangeland areas. The above technical standards reflects the potential <br />productivity of the soils replaced in the reclaimed areas and the climatic conditions of the <br />general area. <br />10.3 Species Diversity <br />Since the new dryland pasture area is predominately crested wheatgrass, the species <br />diversity of the reclaimed areas will be set to a higher standard. Establishment of <br />REVISED 11 Nov 09 Tab 22 -21 <br />