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METHODOLOGY FOR VEGETATION SAMPLING / COMPARISON METHODS <br /> Sample Site Selection / Location <br /> The sample layout protocol for revegetation evaluations in 2022 largely followed Colorado Division of <br /> Reclamation, Mining, and Safety (CDRMS) procedures developed by Cedar Creek, and used in previous <br /> bond release efforts at Colowyo,to provide unbiased, representative,and cost-effective data for evaluation <br /> of revegetation. These procedures are designed to better account for the heterogeneous expression of <br /> vegetation within the various reclaimed areas while precluding bias in the sample site selection process. <br /> By design,the procedure is initiated randomly,and thereafter,samples are located in a systematic manner, <br /> along grid coordinates spaced at fixed distances(e.g., 200 ft. x 200 ft. In this manner, representation from <br /> across the entire reclaimed area is forced rather than risking that significant pockets are entirely missed or <br /> overemphasized, as occurs with other sample distribution techniques. <br /> The systematic procedure for designating sample location in the revegetated units occurred in the <br /> following stepwise manner. First, a fixed point of reference was selected from which the location of a <br /> systematic grid could be facilitated for the unit. Second, a systematic grid of appropriate dimensions was <br /> selected to provide a sufficient number of coordinate intersections (e.g., 20 or 45) to be used as sample <br /> sites. Third, a scaled representation of the grid was overlain on a computer-generated map of the target <br /> unit extending along north/south and east/west lines. Fourth, the initial placement of this grid was <br /> implemented by the selection of two random numbers (an X and Y distance) used for locating the first <br /> coordinate from the fixed point of reference, thereby making the effort unbiased. Fifth, where an excess <br /> number of potential sample points (grid intersections) were indicated by overlain maps, the excess points <br /> were randomly chosen for elimination. If later determined that additional samples would be needed to <br /> satisfy sampling adequacy,the eliminated potential sample sites would be added back in reverse order until <br /> enough sufficient sample points were available. Sixth, utilizing a GPS or handheld compass the sample <br /> points were located in the field. <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 is indicated on Figure 1. Depending on logistics, <br /> timing, and access points to the target sampling area,the field crew would occasionally layout a path along <br /> coordinates in one direction and then sample them in reverse order. However, orientation protocol was <br /> always maintained (i.e., in the direction of the next point to be physically sampled). If the boundary of an <br /> area was encountered before reaching the full length of a transect, the orientation of the transect was <br /> turned 900 in the appropriate direction so the transect could be completed. In this manner, boundary <br /> transects were retained entirely within the target unit by "bouncing" off the boundaries. Production <br />