2021-03-15_REVISION - C1981044 (2)

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where the species was observed by total samples. Measurement of success standards diverge between the two bond release blocks for species diversity. For the Strip Pit success of species diversity is measured utilizing the Shannon Weiner Diversity Index (H), combined with four tests; Mandatory Test A and two of the remaining three alternative tests(B, C or D),must be passed. The H value must be greater than 0.8,the four greatest species contributing to the calculated total H must exceed 48 % cover from the revegetated area, and at least four species must contribute more that 5.0% cover to H. For Mandatory Test A,no species may exceed 40%relative cover. This is a technical standard. For details on the development of the index refer to Exhibit 24, The Strip Pit Reclamation Plan and the SL4 application. Species diversity in the Utah Tract derives from the Trapper Mine technical standards. The measures of species diversity success requires at least five principle species, including a minimum of four cool season perennial grasses and one forb species possessing a minimum of 3%relative cover,with no single species exceeding 50%relative cover and no four species in combination contributing more than 80%relative cover. The species diversity requirement meets the criteria outlined in Rule 4.15.8(5). IV. OBSERVATIONS AND FINDINGS Phase I The Utah Tract is an area of reclaimed surface mine spoils overlaying portions of MCM's underground mining areas. The Utah Tract was previously reclaimed by Utah International as part of the Trapper Mine Operations. Reclamation in the Utah Tract comprised of backfilling and grading,topsoil placement, mulching and seeding. These activities were conducted by Trapper Mine between 1979 and 1983. There are no ponds in the Utah Tract. The Postmining topography is shown on Map 2 of the SL4 submittal. The majority of the Strip Pit was reclaimed in 1981,with the remainder reclaimed in 1987. Highwall slopes in the Strip Pit were reduced to a maximum of 31-1:1V,a profile configuration similar to natural drainages found within the permit area. Slopes in the reclaimed area do not exceed 33.3%(3H:IV). In both the Utah Tract and the Strip Pit contour ditches and furrows were constructed on reclaimed slopes to control erosion on the reseeded surface. These features have since filled in with sediment and blend into the reclaimed topography. Vegetation is well established and no evidence of rill, gully or sheet erosion was evident during inspection. Other than one small swale of a former stock tank,no instability or low spots prone to holding water were noted during the inspection. Compliance with Approved Post Minim Topography The Division evaluated the reclamation parcels to determine if the affected areas have been backfilled Permit Number C1981044 Page 13 of 25