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2.2 Determination of Ground Cover <br />Ground cover at each sample point was determined utilizing the point - intercept methodology as <br />illustrated on Exhibit 1. As indicated in this figure, Cedar Creek utilizes state -of- the -art instrumentation it <br />has pioneered to facilitate much more rapid and accurate collection of data. A transect of 10 meters <br />length was extended in the direction of the next sampling location of each systematically located sample <br />point. At each one -meter interval along the cover transect, a "laser point bar" was situated parallel to, <br />and approximately 4.5 feet vertically above the ground surface. A set of 10 readings was recorded as to <br />hits on vegetation (by species), litter, rock ( >2mm), or bare soil. Hits were determined at each meter <br />interval by activating a battery of 10 low- energy specialized lasers situated along the bar at 10 centimeter <br />intervals and recording the variable intercepted by each of the vertically projected narrow (0.5mm) <br />focused beams (Exhibit 1). In this manner, a total of 100 intercepts per transect were recorded resulting <br />in 1 percent cover per intercept. (Second hits on understory vegetation were not collected owing to the <br />managerial nature of collected data.) All reclaimed area vegetation as well as reference area vegetation <br />(including both herbaceous and shrub strata) were subject to sampling. This methodology and <br />instrumentation facilitates the collection of the most unbiased, repeatable, and precise ground cover data <br />possible. <br />2.3 Sample Adeauacv Determination <br />Sampling of the reclaimed units was restricted to 10 samples for cover due to the managerial nature <br />of collected data (20 for cover on reference areas). However, for informational purposes, sampling <br />adequacy (nn,in) has been calculated for each variable in each sampling unit in accordance with the <br />Cochran formula (below) for determining sample adequacy, whereby the population is estimated to <br />within 10% of the true mean (p) with 90% confidence. <br />When the inequality (nn,in <_ n) is true, sampling is deemed adequate; and n,nin is determined as <br />follows: <br />nmin = (t2S2) / (0.1 X)2 <br />Where: n = the number of actual samples collected with a minimum of 10 in each unit; <br />t = the value from the one - tailed t distribution for 90% confidence with n -1 degrees of <br />freedom; <br />S2 = the variance of the estimate as calculated from the initial samples; <br />X = the mean of the estimate as calculated from the initial samples. <br />CEDAR CREEK ASSOCIATES, Inc. Page 9 Snowcap - Revegetation Evaluation - 2013 <br />