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2.0 SAMPLING METHODS 2.1 Sample Layout The sample layout protocol for the revegetation evaluations in 2006 largely followed procedures detailed in permitting documents. These procedures are designed to better account for the heterogeneous expression of established vegetation within the various reclaimed areas while precluding bias in the sample site selection process. By design, the procedure is initiated randomly, and thereafter, samples are located in a systematic manner, along grid coordinates spaced at fixed distances, e.g. 125 ft. (see Figure 1, lower left corner and Maps 1 & 2). In this manner, "representation" from across the entire reclaimed area is "forced" rather than risking the chance that significant pockets (or seedings) are entirely missed, or overemphasized as often occurs with simple random sampling. sample site selection within the established reference areas occurred in a similar manner. The procedure for sample location within the reclaimed area or reference areas occurred as follows. First, a fixed point of reference that could be relocated from year to year was selected. In 2006, the fixed reference point was the center of a dry sediment pond (see Map 1). Use of this point facilitated location of the systematic grid in the field. Second, a systematic grid of appropriate dimensions (e.g., 125 ft. X 125 ft.) was selected to provide approximately 30 to 35 coordinate intersections within each sampling unit, which could then be used for sample sites. Third, a scaled, computer generated representation of the selected grid was overlain on a computer generated map of the area utilizing north- south and east-west compass points which could be easily established in the field. This overlain grid also facilitated identification of the vegetation type for each sample point. Initial placement of the grid was controlled by the fourth step, selection of a pair of random numbers (between 0 and 200 ft.) to facilitate location of the initial coordinate point from center of the sediment pond. In 2006 these random coordinates were 101'(west) and 66' (south) for the revegetated Riparian Area and 62'(west) and 56' (south) for the revegetated Grassland Area. Fifth, utilizing a hand held surveying compass and hip-chain (or pacing techniques) all sample points were located in the field and flagged. The locations of all sample sites utilized during 2006 sampling efforts are indicated on Maps 1 and 2. Once a selected grid point was located in the field, sampling transacts were always oriented in the direction of the next site to be physically sampled to further limit any potential bias while facilitating sampling efficiency. This orientation protocol follows that which is indicated on Figure 1. Depending on logistics, timing, and access points to the target sampling area, the field crew would occasionally layout a set of points along coordinates in one direction and then sample them in reverse order. However, CEDAR CREEK ASSOCIATES, INC. Page 4 Blue Ribbon Mine - 2006 Phase III Bond Release Evaluation