2016-07-28_REVISION - C1981008 (2)

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above the ground surface. A set of 10 readings was taken specifically to record hits on vegetation (by 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. Ground cover transects were implemented at every sample point in the Phase III area, whereas ground transects were not implemented on every third sample point in the reference areas for the 2015 evaluation efforts. Every third sample point was evaluated for production only. 2.3 Determination of Current Annual Production At each sample site, current annual production was collected from a 1/2 m2 quadrat frame placed one meter and 90° to the right (clockwise) of the ground cover transect to facilitate avoidance of vegetation trampled by investigators during sample site location (Figure 1). From within each quadrat, all above ground current annual vegetation within the vertical boundaries of the frame were clipped and bagged separately by life form as follows: Perennial Grass Perennial Forb Annual Grass Annual Forb Sub shrubs Noxious Weeds (if found) All production samples were returned to the lab for drying and weighing. Drying was conducted at 105° C until a stable weight was achieved (24 hours). Samples were then re -weighed to the nearest 0.1 gram. 2.4 Sample Adequacy Determination Sampling within each unit (Phase III Bond Release Block or Reference Area) was conducted to a minimum of 30 cover and production samples (45 production sample on Reference Area in 2015). 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 nmi,,, whereby the population is estimated to within 10% of the true mean (N) with 90% confidence. When the inequality (nmi„ <_ n) is true, sampling is deemed adequate; and nmi„ is determined as follows: Page 10