2011-01-18_REPORT - C1981041 (2)

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2.4 Determination of Woody Plant Density Belt transects were co- located with the ground cover points to obtain a reasonable estimate of the woody plant density of the mine site. At each of the sample sites in the larger revegetated areas ( <1.5 acres), a 2 -meter wide by 50 meter or 4 meter by 25 meter long belt transect (depending on the distance to the next sample point) was established in the direction of the next sampling point (typically in a cardinal compass direction — see Figure 1). Then within each belt, all woody plants (shrubs, trees, sub - shrubs, and succulents) were enumerated by species. Determination of whether or not a plant could be counted was dependent upon the location of its main stem or root collar where it exited the ground surface with regard to belt limits. Sample adequacy was determined for informational purposes only. On sampling areas smaller than 1.5 acres, total counts of live shrubs were conducted. This required systematically walking the entire unit and recording every live shrub within that unit. 2.5 Sample Adequacy Determination Sampling of the individual units was restricted to 10 or 15 samples (20 for reference areas) for cover, production, and woody plant density due to the managerial nature of collected data. However, for informational purposes, sampling adequacy (n has been calculated for each variable in each sampling unit in accordance with the Colorado guideline (April 18, 1995) formula for sample adequacy when statistical testing is not required, as follows: nmin = (t I (0.1x) Where: n = the number of actual samples collected with a minimum of 10 in each unit; t = the value from the t distribution for 90% confidence with n -1 degrees of freedom; 52 — the variance of the estimate as calculated from the initial samples; x = the mean of the estimate as calculated from the initial samples. CEDAR CREEK ASSOCIATES, Inc. Page 11 Snowcap - Revegetation Evaluation - 2010