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2.0 METHODOLOGY FOR VEGETATION SAMPLING / COMPARISON METHODS <br />2.1 Sample Site Selection / Location <br />The sample layout protocol for revegetation evaluations in 2017 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 <br />evaluation of revegetation. These procedures are designed to better account for the heterogeneous <br />expression of vegetation within the various reclaimed areas while precluding bias in the sample site <br />selection process. By design, the procedure is initiated randomly, and thereafter, samples are located in <br />a systematic manner, along grid coordinates spaced at fixed distances (e.g., 200 ft. x 200 ft. as <br />demonstrated in Figure 1 and Maps 2 through 4). In this manner, representation from across the entire <br />reclaimed area is forced rather than risking that significant pockets (or seedings) 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 30) 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 <br />until enough sufficient sample points were available. Sixth, utilizing a GPS or handheld compass the <br />sample points were located in the field. Locations of all sample sites utilized for 2017 sampling efforts <br />are indicated on Maps 2-4. <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 <br />along coordinates in one direction and then sample them in reverse order. However, orientation protocol <br />was always maintained (i.e., in the direction of the next point to be physically sampled). If the boundary <br />of an area was encountered before reaching the full length of a transect, the orientation of the transect <br />6 <br />