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20 SAMPLING METHODS 2.1 Sample Layout The sample layout protocol for the revegetation evaluations in 2000 and 2001 largely followed procedures detailed in permitting documents. These procedures are designed to better atxiount for the heterogeneous expression of revegetated communities 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. 200 ft. (see Figure 1, lower left comer and Maps 1 and 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 happens with simple random sampling. Sample site selection within the extended reference area occurred in an identical manner. The procedure for sample location within the reclaimed area or reference area occurred as follows. First, a fixed point of reference that could be relocated from year to year was selected. This fixed reference point was the southwestern-most point of revegetation for the Water Tank Area (SW of point No. 5 in 2000 and SW of point No. 4 in 2001). Second, a systematic grid of appropriate dimensions (i.e., 200 ft. X 200 ft.) was selected to provide approximately 35 to 40 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 determined in the field. This overlain grid also facilitated identification of the unit type for each sample point (revegetated area vs. reference area), Initial placement of the grid was controlled by the fourth step, selection of a pair of random numbers (between 0 and 200 ft.) ro facilitate location of the initlal coordinate pain[ In 2000, these random coordinates were 88 (East) and 79 (North) and in 2001 were 194 (East) and 103 (North). Fifth, utilizing a hand held surveying compass and hip-chain all sample points were located in the field and flagged. The locations of all sample sites utilized during 2000 and 2001 sampling efforts are indicated on Maps 1 and 2, respectively. Once a selected grid point (sample site) was located in the field, ground cover sampling transacts were always oriented in the direction of the next site to be physically sampled ro 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 sei of points along coordinates in one direction and then sample them in • reverse order. However, orientation protocol was always maintained (i.e. in the direction of the next point Q~3"DA3 ~'Ft• '63~ f~8Q~7A"1'3ffi, ING Page 5 North Thompson Creek Mines Vham 11 S III eonC Release Evaluatlon