2015-10-13_REVISION - C1981014 (18)

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When an adjacent site was sampled in 1980, Keenan, Inc. reported that all warm season grass species contributed 11.92% of the total basal cover or 61.60% of the total relative basal cover. The two most dominant warm season plant species contributed 7.65% of the total basal cover or 39.53% of the total relative basal cover. The four most dominant plant species contributed 9.93% of the total basal cover or 51.32% of the total relative basal cover. When IME sampled this area in 2007, all warm season species accounted for 30.86% of the total plant cover or 79.13% of the total relative cover. The two dominant warm season species contributed 27.54% of the total plant cover or 70.62% of the total relative cover. The four most dominant plant species contributed 30.27% of the total plant cover or 77.61% of the total relative plant cover. LOADOUT RECLAMATION Plant Cover. The results obtained from the sampling of the 23 plant cover transects on the Loadout Reclamation Study Area are presented in Table 24, Loadout Reclamation - 2013 Plant Cover. "Total plant cover" averaged 29.22%, litter cover averaged 34.61 % and "allowable plant cover" averaged 25.65%. Perennial grasses was the dominant plant life form, contributing 21.70% of the total plant cover or 59.31% of the total relative plant cover. Shrubs were the second most dominant plant life form contributing 3.57% of the total plant cover or 12.20% of the total relative plant cover. Annuals was the third most dominant plant category, contributing 3.56% of the total plant cover or 12.21% of the total relative plant cover. Succulents was the fourth most dominant plant form, contributing 0.26% of the total plant cover and 0.89% of the total relative plant cover. Perennial forbs was the fifth most dominant plant form, contributing 0.13% of the total plant cover or 0.45% of the total relative plant cover. Sand Dropseed was the most dominant plant species encountered, contributing 15.52% of the total plant cover or 53.12% of the total relative plant cover. Blue Grama, was the second most dominant plant species, contributing 3.26% of the total plant cover or 11.16% of the total relative plant cover. The third most dominant species was Russian Thistle, which contributed 2.70% of the total plant cover or 9.23% of the total relative plant cover. Rubber Rabbitbrush, was the fourth most dominant plant and contributed 1.78% of the total plant cover or 6.10% of the total relative plant cover. The locations of the 23 cover transects sampled on this site are shown on Map 21, Loadout Reclamation - 2013 Transect Location Map. The sample adequacy calculations in Table 2, 2013 Mine -Statistical Summary and Sample Adequacy Calculations, document that the number of transects required to characterize the "total plant cover" was 4.3 transects and 12.7 transects for "allowable plant cover" at the 90% confidence interval. Since sample adequacy was achieved using the CDMRS sample adequacy equation, for "allowable plant cover" on both the Loadout Reference Area ( N=21 and Nm=11.2) and the Loadout Reclamation Area (N=23 and Nm=12.7) this means that the calculation of the ultimate "allowable plant cover" revegetation success standard can be made by direct comparison. When IME sampled this area in 2010, "total plant cover" averaged 51.30%. When IME sampled this area in 2006, the average "total plant cover" was 44.67%. Forage Production. The results obtained from the sampling of the 30 forage production transects are found in Table 25, Loadout Reclamation — 2013 Production. Forage production averaged 12.81 g/1/4 m2 or 456.5 pounds per acre. Perennial grasses produced 12.62 g/1/4 m2 or 449.8 19