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2.0 SAMPLING METHODS <br />2.1 Sample Layout <br />The sample layout protocol for revegetation evaluations in 2010 followed CDRMS approved <br />procedures developed by Cedar Creek to provide unbiased, representative, and cost - effective data for <br />evaluation of revegetation. This protocol is a procedure designed to better account for the <br />heterogeneous expression of multiple seedings within various reclaimed areas while precluding bias in the <br />sample site selection process. By design, the procedure is initiated randomly, and thereafter, samples <br />are identified in a systematic manner, along grid coordinates spaced at fixed intervals, e.g. 270 ft. (see <br />Figure 1). In this manner, "representation" from across the entire reclaimed area is "forced" rather than <br />risking the chance that significant pockets (or seedings) are entirely missed, or overemphasized as often <br />occurs with simple random sampling. Sample site selection within the reference areas occurred in a <br />similar manner, although grid distribution was visual and dimensions were reduced accordingly to <br />accommodate the smaller polygons. <br />The actual procedure for sample site location occurred as follows. First, a fixed point of reference <br />locatable from year to year was selected. Second, a systematic grid of appropriate dimensions (e.g., 270' <br />X 270' or 95' X 95'.) was selected to provide approximately 50 coordinate intersections within the <br />revegetated area that could then be used for sample sites. (Cover and woody plant density were <br />collected only at every 2 nd point). Third, a scaled, computer generated representation of the selected <br />grid was overlain on a computer generated map of the area. This grid was then rotated 20° or 30° <br />counter - clockwise from the cardinal compass directions * . Initial placement of the grid was controlled by <br />the fourth step, selection of a pair of random numbers (between 0 and 270) used to facilitate location of <br />the initial coordinate point from the fixed reference location. Fifth, using a hand held GPS all sample <br />points were located in the field and sampled. Locations of all revegetation and reference area sampling <br />sites are indicated on Maps 2 through 7. <br />Once a selected grid point was located in the field, ground cover sampling transects were always <br />oriented in the direction of the next site to be physically sampled to further limit any potential bias while <br />facilitating sampling efficiency. This orientation protocol rouows maE wnicn is aiwLowu U11 F I L. •l <br />the boundary of an area was encountered before reaching the full length of a transect, the orientation of <br />the transect was turned 90 in the appropriate direction so the transect could be completed within the <br />* Prior to sampling in 2010, CDRMS expressed concern that revegetation patterns following N -S and E -W <br />orientations (visible from the air) would bias collected data if the systematic grid were laid out along cardinal <br />compass directions. Therefore, Cedar Creek rotated the systematic grid either 20 or 30 in a counter - clockwise <br />direction to avoid any such bias. However, it should be noted that no patterns are visible in the revegetation from <br />ground level; therefore, any potential bias would be negligible at worst. <br />CEDAR CREEK ASSOCIATES, Inc. Page 3 Hamilton Mine - Phase III Bond Release <br />Year 1 of 2 <br />