2018-11-05_PERMIT FILE - C1981044A (3)

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1) review of predisturbance aerial photographs of the EC Mine area, 2) review of soils and topographic maps, and 3) a site inspection to determine location of communities and the spatial relationship to disturbed areas. All of these investigations used to compile the Vegetation Map (Map 20) were completed during the fall of 1980. MethodoloQy The following discussion describes the methodology used to collect the relevant baseline data and to allow the statistical evaluation of the data. The basic intent of the data acquisition program was to insure that a random sampling of the existing vegetation occurred. In addition to obtaining a random sample it was imperative that an adequate sample was obtained to ensure that the mean and variance of the parameters being analyzed were representative of the actual site conditions. The field sample points were selected based upon a random number grid system. An adequate sample was assured by applying the Sendecor-Cochran sample adequacy equation (1967) to the data obtained from the 20 preliminary samples. The sample adequacy test was applied to each of the vegetation parameters being sampled to ensure adequate sampling of the same. These parameters were; 1) herbaceous cover and production, and 2) woody species density. The sample adequacy equation dictates that the mean be within 10 percent of the populations mean at the 80 percent confidence level. The areas sampled for each community were equal to the area of the present disturbance. Therefore, this will affect a 1:1 trade between currently disturbed and undisturbed land. A list of the disturbed areas and acreage is given on Table 35, List of Disturbed Areas, Associated Acreage, and Representative Vegetation Communities. Cropland For cropland areas production was the only parameter evaluated. This information was obtained from the farmers' records for both the irrigated hay field and dryland wheat fields for five-(5) growing seasons. An average annual production value for the five (5) year period will be calculated. Saeebrush Communit The pazameters sampled for the sagebrush community included; 1) herbaceous cover and production, and 2) woody species density. Herbaceous cover by species was used in the Shannon-Weiner index to calculate species diversity. Herbaceous cover data was obtained by using the line intercept method. The utility of this method was discussed by Bonham, et. al. (1980). In the line intercept method the portion of the line intercepted by the plant is recorded and summed over the length of the line to find the cover value. This analysis was performed for each individual species intercepting the line. The transect length was 15 meters long and, as described above, randomly located in the area to be sampled. Special attention was paid in areas of species overlap to ensure that accurate cover data is obtained. If selection of a starting point and the orientation of the line transect indicates that any overlap of two (2) or more transects will occur then new starting points for orientation was randomly selected. Also, if any old roads are traversed by the transect then the transect was interrupted where it crosses the road and started again on the opposite side. The transect was stopped five (5) feet short of and restarted five (5) feet after the road to minimize variability caused by the succession process occurring in the roads. This distance was selected after a visual inspection of the sample sites. Herbaceous production data was obtained by use of a clipped quarter meter squared quadrat. For clarity, the quadrat will be Imxlm/4m. The ZO preliminary quadrats will be placed at the starting point of each of the line transects with the long axis of the quadrat parallel to the line transect. The visually dominant herbaceous species was clipped by Perini[ Renewal No. 4 2.04-30 Revised 3/5/03