2019-10-10_GENERAL DOCUMENTS - C1981010

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success standard for range site A is 52%. The SL 19 Bond Release Block meets and exceeds the reclamation success standard for vegetation cover. The vegetation report shows that the reclaimed parcels are dominated by native perennial grasses. Native perennial graminoids account for 42.9% cover. Of the graminoid cover, 22.5% is composed of Wheatgrass species, 8.4% cover attributed Bluegrasses, 4.3% cover was from Mountain Brome. Further, 10.9% cover is attributed to perennial forbs, annuals and biennial forbs made up 7.2% cover, woody species accounted for 1.0% cover, and noxious weeds accounted for 12.1%. Table 1.2-2 in the SL-19 application provides a summary of the species and life forms sampled. Based on the perennial species of grasses, forbs and shrubs found at the site as indicated in the SL 19 application, it appears the species diversity and composition will support the post-mine land use. While noxious weeds were encountered at the site,they comprised 12.1%,a small percentage of the vegetative cover. Although meeting the species diversity success standard is not a requirement for phase II bond release,the establishment of a diverse and effective reclaimed community that supports the post mining land use allowed the Division to confirm that the reclaimed area is moving towards final reclamation success. Sedimentology The condition of the sediment ponds and any needed maintenance on the ponds receiving runoff from the bond release parcels were evaluated. Each of the ponds observed was functioning adequately and no required maintenance items were noted. With the exception of two stock ponds, one each in parcels FABO 1 and FAB99, each of the ponds receiving run-off from the bond release parcels is also receiving flow from affected lands not under consideration for bond release at this time. In accordance with Rule 3.03.1(3)(b)and with Section III.A.7.a. of the Division's 1995 Guideline Regarding Selected Coal Mine Bond Release Issues, Trapper submitted two evaluations to demonstrate that runoff from each bond release block will result in equivalent or lesser sediment contribution as compared to baseline conditions and similar undisturbed lands. Trapper's bond release application compares pre- and post-mining sediment yields by calculating expected sediment yields for both conditions. Trapper used the LISLE (Universal Soil Loss Equation), and SEDCAD 4 for Windows for this analysis. The LISLE calculates expected average annual soil loss per acre of land (rate of erosion), based on slope, rainfall pattern, soil type and vegetation type. SEDCAD 4 calculates the expected settleable solids concentration in runoff from a precipitation event. Trapper's two sets of pre-mining and post-mining sediment control demonstration models comprise Appendix 3 (SEDCAD 4)and Section 1.4(USLE),of the bond release application. LISLE Comparison: Only the "C" factor varies between the pre-mining and the post-mining calculations; all other variables are constant for pre-and post-mining. The C factor takes into account land use, vegetative canopy cover, effective cover and grass type. The pre-mining calculation utilized baseline vegetation cover values from the permit application (Table 2.3-13 and 4.4-2). The post-mining calculation uses vegetation cover data for the disturbed area collected in 2017. The variables used in the calculations are reasonable for making the comparison. The Permit Number C 1981010 SL19