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. 2.0 SAMPLING METHODS 2.1 Sample Layout The sample layout protocol for the revegetation evaluations in 2000 largely followed procedures detailed in permitting documents. These procedures are designed to better account for the heterogeneous expression within the various redaimed areas while preluding 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. 200 ft. (see Fgure 1, lower left comer and Map 1). In this manner, `Yepresentation" from across the entire redaimed area is "forced" rather than risking the chance that significant pockets (or seedings) are entirely missed, or overemphasized as often happens with simple random sampling. Sample sffe seledion within the extended reference area occurred in an identical manner. The procedure for sample location within the relaimed area or reference area occurred as follows. Frst, a fixed point of reference that could be relocated from year to year was seleded. In 2000, the fixed reference point was the southwestern-most point of revegetation for the Water Tank Area (SW of point No. 5). l)se of this point fallitated location of the systematic grid in the field. Second, a systematic grid of appropriate dimensions (i.e., 200 ft. X 200 ft.) was seleded to provide approximately 35 to 40 coordinate intersedions within each sampling unit, which could then be used for sample sites. Third, a scaled, computer generated representation of the seleded 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 unit type for each sample point (revegetatod area vs. reference area). Inffial placement of the grid was controlled by the fourth step, selection of a pair of random numbers (between 0 and 200 ft.) to fadlitate location of the initial coordinate point from the utility pole. In 2000 these random coordinates were 88 (East) and 79 (North). Rfth, utilizing a hand held surveying compass and hip-chain (or paing techniques) all sample points were located in the field and flagged. The locations of all sample sites utilized during 2000 sampling efforts are indicated on Map 1. Once a seleded grid point was located in the field, ground cover sampling transeds were always oriented in the direction of the next site to be physically sampled to further limft any potential bias while fadlffating sampling effidency. This orientation protocol follows that which is indicated on Fgure 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 ~l6®L~ Q~®S R~'[DLRf®4a8, rcc. Page 4 North Thompson Creek Mines PMSe 11 6111 9ond Release Evaluation