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the 1985 and 1998 reclamation areas. In Wadge Pasture, woody plant density samples were • collected using atwo-stage design. SINGLE-STAGE SAMPLING: Each reclamation and reference unit identified in the SCC Scope of Work was gridded and numbered. Grid cell size was 100 feet X 100 feet in reclaimed areas, and 50 feet X 50 feet in reference areas. These grid cells were placed contiguously by hand on maps of 1:4,800 scale. Sample locations were selected from the numbered grid cells. The SCC-assigned numbers of samples fora given parameter in a given area reflected previously experienced sample variability or the level of precision required in a given area. Random numbers generated by computer were used to select grid cells, in the middle of which a sample point was placed, and recrorded on the field maps. These sample points were located as accurately as possible in the field using aerial and topographic maps and pacing from knowh locations. Cover and woody density transects were located and oriented using a blind throw of a meter stick. Final location of each herbaceous production quadrat was accomplished with a blind throw of the sampling hoop made from the origin of the associated cover/woody plant density transect. At each cover/woody density sampling location, the slope (percent) and aspect of the site (in degrees not corrected for magnetic declination) were determined and recorded, as was the orientation of the transect (in degrees not corrected for magnetic declination). TWO-STAGE SAMPLING: The Wadge Pasture was sampled for woody plant density using atwo-stage statistical design as set forth in Chapter 10 of Cochran (1977). Two-stage sampling is undertaken by dividing the • entire area to be sampled into smaller units of equal area that are known as "primary units". A subset of primary units is randomly selected and each selected primary unit is then divided into "subunits". Randomly selected subunits are sampled and represent the second-stage of sampling. Wadge Pasture was divided into 20 equal-sized primary sample units and 15 of these were randomly selected to be sampled (see Map 2). Each primary sample unit was approximately 15 acres in size. Within each selected primary sample unit, three of the 607 potential secondary units within each primary unit were randomly chosen in the same fashion that was used for single stage random sampling. These points were then placed on the field maps and located as accurately as possible in the field. Three woody plant density samples were placed in each of the fifteen primary units for a total 45 woody plant density quadrats. For statistical purposes, sample size (n) is fifteen. Sample Adequacy Calculations Sample adequacy calculations parameter estimation without hypothesis testing were carried out using the formula as prescribed by the Colorado Mined Land Reclamation Board (CMLRB 1995): t2 s2 (d~z where: to =one-tailed t-value with (n-1) degrees of freedom, a=0.10 s2 =sample variance • d = 0.1 (level of precision or desired detectable reduction)