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<br />• 22 Determinatlon of Ground Cover <br />Ground cover at each sample point was determined utilizing the point-intercept methodology as <br />illustrated on Figure 1. As indicated in this figure, Cedar Creek utilizes new state-of-the-art <br />instrumentation it has pioneered to facilitate much more rapid and accurate collection of data. A Vansect <br />~ of 10 meters length was extended in the direction of the next sampling location from the flagged center of <br />each systematically located sample point. At each one-meter interval along the transact, a "laser point <br />bar" was situated parallel to, and approximately 4.5 to 5.0 feet vertically above the ground surtace. A set <br />of 10 readings was recorded as to hits on vegetation (by species), litter, rock, or bare soil. Hits were <br />~ determined at each meter interval by activating a battery of 10 low-energy specialized lasers ~ situated <br />along the bar at 10 centimeter intervals and recording the variable intercepted by each of the vertically <br />projected narrow (0.020') focused beams (see Figure 1). In this manner, a total of 100 intercepts per <br />transact were recorded resulting in 1 percent cover per intercept. All reclaimed area vegetation as well as <br />~ reference area vegetation (including both herbaceous and shrub strata) were subject to sampling. This <br />methodology and instrumentation facilitates the collection of the most unbiased, repeatable, and precise <br />ground cover data possible. <br />1• <br />2.3 Sample Adequacy Determinatlon <br />Sampling in four targeted areas continued until: 1) a minimum of 15 samples had been collected and <br />~ 2) sampling adequacy (nm„J had been attained in accordance with the promulgated Colorado guideline <br />(April 18, 1995) formula for sample adequacy when statistical testing is not required, as follows: <br />1 <br />Where: n =the number of actual samples collected with a minimum of 15 in each unit; <br />f =the value from the t distribution for 90% confidence with n-1 degrees of freedom; <br />~ a 2 =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 />1 <br />• .. lasers uEtized for this instrument are state-oi-the-art and of speaalized design to emit a urrique electro-magnetic <br />wavelength visible under full sunlight, a conditan prevausly not possble wilh portable low-energy lasers. <br />Page 7 <br />1 <br />