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The soil types corresponding to the Irrigated Pasture Reference Area and pre -mine soil mapping <br />units are based on the USDA - NRCS Soil Survey of San Miguel Area, which was compiled in <br />the field from 1978 to 1984. The report was published in 1986. This survey can be obtained on <br />the internet at http: / /offices.usda.gov/ scripts /nd1SAPI.d11 /oip public/USA map. <br />At the NH2 Mine, WFC utilized a soil correction factor to adjust for different productivity levels <br />of the different soil types since there had been no valid statistical comparison of any baseline <br />predisturbance Irrigated Pasture areas for the proposed Irrigated Pasture Reference Area. <br />However, intensive baseline vegetation surveys performed during the summer of 2009 on four <br />different irrigated pasture areas on and immediately adjacent to the NI-N Mine site, on the <br />Garvey, Meehan, Glasier and Carver properties, clearly established that there is a high degree of <br />statistical similarity between the baseline predisturbance areas of Irrigated Pasture and the <br />previously approved Irrigated Pasture Reference Area. Given this similarity and the fact that a <br />pure random sampling of the Irrigated Pasture Reference Area results in a weighted average that <br />takes into consideration the differences in soil types, relative to the NHN Mine no soil correction <br />factor is proposed for the proposed postmining revegetation success monitoring. <br />Revegetation Success Criteria and Statistical Procedures - Reclaimed Irrigated Pasture. <br />Revegetation will be deemed adequate if vegetation cover and herbaceous production at the <br />reclaimed site is at least 90% of the vegetative cover at the reference area and herbaceous <br />production is at least 90% of the reference area standard. One of the statistical comparison <br />methods in DRMS Regulations 4.15.11(2) subsections (a), (b), or (c) will be used to document <br />revegetation success of all irrigated pasture reclaimed areas. <br />As allowed in Rule 4.15.8(5), species diversity can be quantified using either plant cover or <br />forage production comparison. When TR -58 at the NH2 Mine was approved, the CDMRS <br />required that in lieu of a species diversity standard for the reclaimed irrigated pasture areas there <br />would instead be a forage quality diversity standard. Therefore, the following forage quality <br />diversity standard was proposed and approved for the NH2 Mine and is proposed for the NHN <br />Mine as well: <br />Section 2.05.4(2)(e) Page 17 January 2012 <br />