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Sample locations in reclaimed areas were randomly plotted by use of an internal script routine within ArcView software. Minimum spacing between sample points was 170 feet (one 50 m transect length). The SCC-assigned number of samples for a given parameter in a given area reflected previously experienced sample variability or the level of precision required for that area. In the extended reference areas, each reference unit was gridded and numbered. Grid cell size was 200 feet X 200 feet. These grid cells were placed contiguously by hand on maps of 1:4,800 scale. Sample locations were selected as the center points of grid cells selected using random numbers generated by computer. Sample points were located in the field using topographic maps. Cover and woody plant density transects were located and oriented using a blind throw of a meter stick. The final location of each herbaceous production plot was chosen with a blind throw of the sampling hoop made from the origin of the associated coverlwoody plant density transect. At each cover/woody plant density sampling location, the slope (percent) and aspect of the site were determined and recorded, as was the orientation of the transect (in degrees not corrected for magnetic declination). STATISTICAL METHODS Sample adequacy calculations for parameter estimation were carried out using the formula as prescribed by the Colorado Mined Land Reclamation Board for parameter estimation without hypothesis testing (DMG 1995): taZ sz Nmin= (d X )z where: I to =one-tailed t-value with (n-1) degrees of freedom, a=0.10 sZ =sample variance d = 0.1 (0.15 for woody plant) (level of precision or desired detectable reduction) x = sample mean Confidence Limits Confidence limits for comparisons to reference areas and technical standards were calculated using a 1-tailed t-value for alpha error probability of 0.10 at (n-1) degrees of freedom multiplied by the standard error of the mean of the sampled area. 4