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pasture exceeded the live vegetative cover sampled on the Dryland Pasture reference area. Few annual <br /> or biennial species were encountered on the reclaimed dryland pasture BRB,with the annual/biennial <br /> relative cover below the 10%relative allowable cover. No noxious weed species were counted in the <br /> sampling, attesting to the overall health of the re-established dryland pasture. <br /> The operator has exceeded the vegetative cover requirement for the Dryland pasture bond release block. <br /> The Irrigated Pasture Phase II BRB ground cover was comprised of 93.5%live vegetation, 0%rock, <br /> 3.3%litter, and 3.2%bare ground. Of the live vegetative cover, 99.8%relative cover was attributable to <br /> perennial species,and 0.21%relative cover was contributed by annual or biennial species. No noxious <br /> species were measured during the sampling effort. In comparison,the Irrigated Pasture Reference area <br /> exhibited 8 8.3 5%live vegetation, 0%rock, 9.0%litter, and 2.6%bare ground. In the Irrigated Pasture <br /> Reference area the vegetative component was divided between 98.8%relative cover due to perennial <br /> species, 1.1%relative cover due to annual or biennial species,and only 0.1%due to noxious species. <br /> The operator has exceeded the Phase II bond release vegetative cover requirement for the Irrigated <br /> Pasture bond release block. <br /> Sedimentology Demonstration <br /> ERMR used the revised universal soil loss equation(RUSLE 1.06c)to demonstrate that the post-mining <br /> reclaimed parcels sediment loss was equal to or less than pre-mining condition. For the Dryland Pasture <br /> BRB Slope two different slopes(slopes used are shown on SL22 Map 1 "2018-2019 Phase II <br /> Revegetation Evaluation Report"by Cedar Creek Associates, Inc.)were evaluated for sediment yields. <br /> Slope 1 was calculated to exhibit soil loss of 0.013 tons/acre/year in the pre-mining condition, and 0.20 <br /> tons/acre/year post-mining. Slope 2 was calculated to lose 0.297 tons/acre/year in the pre-mining <br /> condition,but only 0.016 tons/acre/year post-mining. <br /> For the Irrigated Pasture Bond Release Block,again,two slopes were used for the sedimentology <br /> demonstration. These slopes are shown on SL22 Map 1 referenced in the preceding paragraph. Pre- <br /> mining conditions on Irrigated Pasture BRB Slope 1 were calculated to lose 0.007 tons/acre/year, and <br /> Slope 2 would lose 0.025 tons/acre/year. The Irrigated Pasture BRB post-mining soil loss is predicted to <br /> be 0.008 tons/acre/year on Slope 1, and 0.004 tons/acre/year on Slope 2. <br /> The operator provided sediment demonstration on two slopes within the prime farmland/irrigated pasture <br /> bond release block. The operator used RUSLE calculations to determine that the predicted soil <br /> loss/acre/year would be less on the reclaimed cropland than on the pre-mining cropland on both slopes. <br /> Slope 1 pre-mining predicted soil loss was 0.014 tons/acre/year. The post-mining predicted soil loss on <br /> this same slope is predicted to be 0.004 tons/acre/year. On slope 2 the pre-mining predicted soil loss was <br /> calculated to be 0.007 tons/acre/year. The post-mining soil loss for slope 2 is predicted at 0.005 <br /> tons/acre/year. These calculations were based upon accepted calculations of the RUSLE formula. <br /> Calculated post-mining sediment from the bond release blocks are within acceptable predicted ranges. <br /> Flow rates and total suspended solids(TSS)concentrations in Tuttle draw have shown a slight increase <br /> between pre-mining and post-mining reclamation. However, slight increases in these two parameters <br /> were also observed upstream of the mining activities. Observations in Calamity Draw pre-mining and <br /> Permit Number C1981-008:SL22 Page 11 of 17 <br />