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Sampling Design <br />Before field work commenced, the permit document, amendments to the permit, baseline <br />data, any prior sampling data, applicable maps, and aerial photographs were reviewed to <br />evaluate topography, reclamation timing, seed mixes, revegetation methods, and <br />applicable revegetation standazds. <br />A 1:1200 scale (1"=100') map ofthe reclaimed mine site (Figure 1, Mine Facilities) was <br />used to delineate the sampling area within the former permit area. Computer generated <br />random numbers were used to establish a pool of x,y coordinates for a Cartesian grid that <br />was overlain upon the reclaimed azea. From these points, sample sites were randomly <br />established. Twenty random sample locations were initially established for the reclaimed <br />area. Of these 20 locations, 15 were utilized to ensure representative sampling over the <br />entire reclaimed azea. Sample sites were located in the field through pacing from known <br />landmarks depicted on aerial photographs. Figure 1 illustrates the location of the sample <br />point locations. <br />Field Sampling <br />Vegetation Cover and Species Composition <br />Vegetation cover was estimated by the use of the point-intercept method. A laser (ten) <br />' point frame was used to minimize instrument error and maximize precision and observer <br />accuracy. Cover transacts were 25 meters in length, with ten sample data points collected <br />at 5.0 meter intervals along the transact on both sides ofthe transact centerline, for a total <br />' of 100 points per transact. Transact orientation was randomly determined by random <br />numbers generated (between 1 and 360). In no event were transacts allowed to extend <br />within ten feet of revegetated azea boundaries, to minimize impacts from "edge effect." <br />For statistical purposes, each cover transact served as a sample unit. Data points recorded <br />the first vertical "hit" on vegetation (as determined by the laser point frame), soil (bare <br />ground), rock, or litter. The data were summazized by computing mean cover, relative <br />cover (percent of total vegetation cover attributed to each species), and species <br />composition. Species composition information was computed from vegetation cover data <br />using a ratio of individual species cover to total vegetation cover. <br />Production <br />Biomass production data were obtained using a harvest method. All of the current year's <br />growth included within aone-half squaze meter quadrat was clipped at both ends of each <br />transact. Succulents, noxious weeds, and cushion plants were not clipped. Clipped <br />biomass was placed in paper bags, and dried in Colorado State University's Rangeland <br />Ecosystem Science Laboratory forced air ovens for 24 hours at 105°C. Samples were <br />weighed on an appropriate scale to the neazest tenth of a gram and reported in g/m2 and <br />Ibs/acre. Clipped samples less than 0.10 grams were reported as trace samples. Average <br />paper bag weight was subtracted from weighted samples. <br />