2015-10-13_REVISION - C1981014 (12)

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areas in calculating the final warm -season species diversity revegetation success standard." The final warm season grass species diversity standard is calculated using the following method. The total acreage of the four currently approved reference areas is 5.79 acres, with the following acreages corresponding to each reference area. The Refuse Pile Reference Area 2.80 acres; the New Portal Reference Area 1.68 acres; the Old Portal Reference Area 0.29 acres; and, the Loadout Reference Area 1.02 acres. Based upon these acreages, the corresponding weighting factor for each of these four reference areas would be 48.35; 29.02; 5.01; and, 17.62 %, respectively. Examination of the plant cover data for these four reference areas reveals that there are 2, 3, 1 and 2 warm season grass species having relative cover values of greater than three percent respectively for these four reference areas. Multiplication of these four weighting factors by these warm season species having greater than three percent relative cover, yields the following weighted factors for each of the four reference areas, 0.9670; 0.8706; 0.0501; and 0.3524, respectively. Addition of these four weighted factors yields a weighted average warm season revegetation success index value for 2014 of 2.24 warm season species. The reference area warm season grass species diversity index for 2013 was 2.13. The revegetation success diversity criteria for warm season grass species for the four combined reclaimed areas located at the Southfield Mine and Southfield Loadout is calculated using the following method. The total acreage of the four reclaimed areas located at the Southfield Mine and Southfield Loadout is 81.87 acres, with the following acreages corresponding to each reclaimed area. The Refuse Pile Reclamation 46.48 acres; the Vento Portal Reclamation 10.22 acres; the Corley Reclamation 11.71 acres; and, the Loadout Reclamation 13.56 acres. Based upon these acreages, the following weighting factor for each of these four reclaimed areas would be 56.66,% 12.48 %, 14.30 % and 16.56 %, respectively. Examination of the plant cover data for these four reclaimed areas documents that there are 3, 4, 4, and 3 warm season grass species having greater than three percent relative cover, respectively, for these four reclaimed areas. Multiplication of these four weighting factors by these warm season species having greater than three percent relative cover, yields the following weighted factors for each of thee four reclaimed areas; 1.6995, 0.4992, 0.5720 and 0.4971, respectively. Addition of these four weighted factors yields a weighted average warm season grass species index value for these four reclaimed areas of 3.27. The corresponding value from the 2013 sampling was 2.97. 6ince the 2014 reclamation warm season grass index value of 3.27 is greater than the undisturbed reference areas warm season grass index value of 2.24, it can be concluded that the warm season grass species diversity standard for the reclaimed areas at the Southfield Mine and Southfield Loadout areas has been satisfied. CONCLUSIONS Plant Cover. With respect to the successfulness of revegetation efforts on the Phase III 2014 Reclamation Study Areas at the Southfield Mine, since sample adequacy was achieved for the "allowable plant cover" sampling on the on all of these three reference areas (N=76 and Nm= 5.9) and for all three reclaimed areas (N=45 and Nm=5.6) and since weighted average plant cover" on the reclaimed areas (41.78 %) exceeds the calculated revegetation success standard for "allowable plant cover," obtained from the sampling of the three reference areas (35.31 %), it can be determined by direct comparison that the "allowable plant cover" growing on all of the reclaimed sites would be considered successful with respect to the final bond revegetation success standard for "allowable plant cover." For the Southfield Loadout site, since sample adequacy was achieved for "allowable plant cover" on the Loadout Reference Area (N=15 and Nm=13.9) and for corresponding Loadout Reclamation (N=21 and Nm=20.2) and since average "allowable plant cover" on the Loadout Reclamation (39.10 %) exceeds the calculated revegetation success standard for "allowable 30