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I 1 1 l ' 2.0 METHODS 2.1 SAMPLE DESIGN ' The revegetated areas providing drainage to the three sediment control ponds (22-P5, 22-P 6, and 22-P7) were randomly sampled for vegetative cover. ' The areas draining into the three sediment ponds were considered as one sample area. A grid scaled to 50 ft by 50 ft was established on the sediment control map in the areas to be sampled. Pairs of random numbers were used as Cartesian coordinates to locate sample points. Sample points ' were located in the field by use of a contour map and pacing where necessary. See Figure 1. ' 2.2 COVER SAMPLING ' Vegetation cover was estimated using a point-intercept method along randomly located and oriented transects (Mueller-Dombois and Ellenberg 1974). Fifty data points were sampled along a 50 m transect. Paired points were located on opposite sides of the transect, at 2 m intervals and ' 0.5 m from the transect line. For purposes of evaluating statistical adequacy, each transect (i. e., fifty data points) comprised one "sample." ' A siting device was rigidly mounted on an adjustable tripod to assist in vertical orientation and point stabilization. The siting device was equipped with fine cross-hairs to facilitate precise point definition. At each sample point, the first hit or interception along a vertical ' projection was recorded ds vegetation (by species), rock, soil, or litter. Vegetation intercepted below the first hit was recorded separately as other hits. Only first hits were used in calculating absolute cover. All ' vegetation hits were used to calculate relative vegetation cover. 2.3 SAMPLE ADEQUACY Sample adequacy for cover was calculated with the following formula: = t2s2 nmin (dx)2 ' where nmin = minimum sample size t = t value for 2-tailed test at 90% confidence ~ ' s = sample standard deviation (n-1) d = desired detectable change in the mean (0.1) z =sample mean -2-