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Ground cover at each sample point was determined utilizing the point- intercept methodology as <br />illustrated on Figure 1. As indicated on 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 length <br />was extended in the direction of the next sampling location from the flagged center of each systematically <br />located sample point. At each one -meter interval along the transect, a laser point bar was situated parallel <br />to, and approximately 4.5 to 5.0 feet vertically above the ground surface. A set of 10 readings was taken <br />specifically to record hits on vegetation (by species), litter, standing dead, rock ( >2mm), or bare soil. Hits <br />were determined at each meter interval by activating 10 low- energy specialized lasers" situated along the <br />bar at 10 centimeter intervals and recording the variable intercepted by each of the narrowly focused <br />(0.02' beams (Figure 1). In this manner, a total of 100 intercepts per transect were recorded resulting in <br />1 percent cover per intercept. This methodology and instrumentation facilitates the collection of the most <br />unbiased, repeatable, and precise ground cover data possible. Identification and nomenclature of plant <br />species follows Colorado Flora: Western Slope (Weber and Wittman, 1996). <br />2.3 Sample Adequacy Determination <br />Sampling within each unit was conducted to a minimum of 25 or 30 samples for Phase II area <br />sampling. From these preliminary efforts, sample means and standard deviations for total non - overlapping <br />vegetation ground cover were calculated. For non - monitoring applications, the typical procedure is that <br />sampling continues until an adequate sample, nm;,,, has been collected in accordance with the Cochran <br />formula (below) for determining sample adequacy, whereby the population is estimated to within 10% of <br />the true mean (p) with 90% confidence. <br />Lasers utilized for this instrument are state -of- the -art and of specialized design to emit a unique electro- magnetic <br />wavelength visible under full sunlight, a condition previously not possible with portable low- energy lasers. <br />CEDAR CREEK ASSOCIATES, INC. Page 9 Bowie #1 Mine - 2013 <br />Phase II Bond Release Report <br />