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Total vegetative cover in the dryland pasture reference area was 29.9%. Composition, based on <br />relative cover, in the reference area was 0.7% annual grass, 47.2% annual forbs, 16.7% shrubs, <br />3.7% perennial grasses and 31.8% perennial forbs. The dominant species were Western <br />stickweed (an annual forb) at 10% total cover (33.4% relative cover), and two perennial forbs, <br />globemallow at 6.9% total cover (23.1 % relative cover) and groundsel at 2.7% total cover (9.0% <br />relative cover). The relative cover of redstem filaree in the reference area is 0.3%, significantly <br />less than the relative cover of the species in the reclaimed area. No other noxious weed species <br />were observed in the reference area. <br />The vegetative cover standard from the dryland reference area is 29.9%. The cover in the <br />reclaimed dryland pasture was 35.2%. Since redstem filaree exceeded 10% relative cover in the <br />reclaimed area at 20.7% relative cover, the excess must be subtracted from the total cover. The <br />excess is considered to be approximately one-half of the relative cover (20.7-10.0) and a <br />corresponding one-half of the total cover for redstem filaree (7.3-3.6). The adjusted total cover <br />value for the reclaimed dryland pasture is 31.6%. With the adjusted cover value, the reclaimed <br />area still exceeds the cover from the reference area and is considered successful for the Phase II <br />bond release. <br />New Horizon is encouraged to develop a management plan for the control of redstem filaree in <br />the reclaimed area. The Montrose County Weed Supervisor may be able to assist with a <br />management and control plan. <br />Sedimentology <br />WFC's Phase II bond release request of 300.0 acres at the New Horizon Mine #2 includes 238.8 <br />acres of irrigated pasture and 61.2 acres of dryland pasture. The land requested for this bond <br />release was originally dryland and irrigated pasture. A comparison must be made of the <br />sediment loss from the reclaimed area to that of the original land prior to mine disturbance. <br />WFC's bond release application compares pre- and post-mining sediment yields by calculating <br />the expected sediment yields for both conditions. WFC used the Revised Universal Soil Loss <br />Equation (RUSLE) to calculate the expected average annual soil loss per acre. Vegetation <br />statistics for Cover Factor "C" were used in the calculation from the reclaimed areas (2007 cover <br />data) and from the same areas prior to mining in 1987. Pre- and post-mine topography was used <br />to determine the Length Slope Factor "LS" which like the "C" factor varied between the pre- <br />mine and post=mine land conditions. All other factors including R, K, and P did not vary and <br />remained constant from pre-mine to post-mine conditions. Vegetation cover differences and <br />percent slope reductions from the reclaimed areas and the pre-mine areas accounted for the <br />differences in the RUSLE factors. <br />Pre-mine condition irrigated pasture and dryland pasture (data from year 1987) were both <br />compared to post-mine condition irrigated and dryland pasture (data from year 2007). The <br />results of these calculations demonstrated that sediment loss in tons per acre/year was 0.217 <br />versus 0.194 for pre-mine versus post-mine irrigated pasture and 0.817 versus 0.472 for pre-mine <br />versus post-mine dryland pasture, respectively. In both cases the sediment loss was less for the <br />reclaimed lands than it was for the pre-mine land conditions. <br />12