2016-10-14_REVISION - C1981041 (2)

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species), litter, (including standing dead), rock (>2mm), or bare soil. Hits were determined at each meter interval by activating a battery of 10 low-energy specialized lasers situated along the bar at 10 centimeter intervals and recording the variable intercepted by each of the narrowly focused (0.02' beams (Figure 1). In this manner, a total of 100 intercepts per transect were recorded resulting in 1 percent cover per intercept. This methodology and instrumentation facilitates the collection of the most unbiased, repeatable, and precise ground cover data possible. To facilitate diversity calculations, second hits were recorded when an overstory shrub stratum was present. However, these second hits were not included in the determination of ground cover. 2.3 Sample Adequacy Determination Sampling within each unit (Phase II Bond Release Block or Reference Area) was conducted to a minimum of 30 cover and production samples. From these preliminary efforts, sample means and standard deviations for total non -overlapping vegetation ground cover were calculated. The Cochran formula (below) for determining sample adequacy was used to calculate nmin, whereby the population is estimated to within 10% of the true mean (p) with 90% confidence. When the inequality (nmin <_ n) is true, sampling is deemed adequate; and nmin is determined as follows: nmin = (t 25 2) / (0.1 X )2 where: n = the number of actual samples collected (initial size = 27/30) t = the value from the one -tailed t distribution for 90% confidence with n-1 degrees of freedom; s Z = the variance of the estimate as calculated from the initial samples; x = the mean of the estimate as calculated from the initial samples. If the initial samples do not provide a suitable estimate of the mean (i.e., the inequality is false), a reverse null success evaluation which does not require adequacy would be employed (Rule 4.15.11 (2)(c)). Sample adequacy results are presented on Table 1. 5 Revised 10/16