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1 <br />Post-reclamation Investigation <br />' Vegetation data for this study were collected on 3-4 August 1992, 19-20 July 1993, and 28-30 <br />June 1995. Vegetative cover and woody plant density were sampled in 1992, 1993, and 1995. <br />Herbaceous production sampling was conducted in 1993 and 1995. The 1995 study also included <br />' woody plant rooting depth sampling and vegetation sampling of the preselected reference plot. <br />No data were collected in 1994. Soil and refuse sampling was conducted on August 13 to <br />determine potential upwazd migration of salts from the refuse material into the cover soil. <br />1 Methods <br />' Vegetative Cover <br />' Vegetative cover data were collected in 1992, 1993, and 1995. This cover sampling was <br />conducted using 30-meter long point-intercept transects. Five to 10 transects were sampled in <br />each plot. Each transect was randomly selected using a random numbers table grid. Transects <br />' were randomly located on a line extending along the uphill axis of each plot. Transects were laid <br />across the plots perpendicular to the base axis. In 1995, the reference plot vvas also sampled in <br />a similaz manner. Sample adequacy was set such that estimates are within 10% of the true mean <br />' at the 90% level of statistical confidence. Adequacy was calculated using the Snedecor-Cochran <br />sample adequacy formula (Equation 1). <br />tz sZ <br />N~ _ <br />(dx)z <br />Where: <br />N = required number of transects or quadrants, <br />t = the t„b„value for adouble-tailed t-test with n-1 degrees of freedom at the 90% confidence <br />level, <br />sZ = sample variance, <br />d = 0.1 (the precision level for the estimate of the mean to be within 10% of the actual mean), <br />and <br />x = sample mean. <br />Ground cover was evaluated along each transect by sampling one point at 0.3 meter (1 fr.) <br />intervals along each transect. This method was used instead of the 10-point frame method due <br />to the close proximity of transects, vaziabiliry of cover in some plots, and the use of these same <br />transects for the woody plant density analysis. Cover was classified as vegetation, litter, rock. <br />or baze ground. Vegetation was further classified by species. Each transect consisted of 100 <br />sample points. Each point was determined by projecting an optical point projection device <br />(model 2) vertically do«nward to the sample location on the transect and recording all "hits" on <br />vegetation. The "hits" were used to estimate total vegetative canopy cover for each transect <br />according to equation 2. <br />~~a-m~.iw~s-tea 7 <br />