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• RECLAMATION PLAN Pre-Mine Vegetation Mapping and Sampling "Pre-mine" vegetation mapping delineated three (3) vegetation communities within the EPA. No communities were mapped within the WPA as this area was apparently exempted from vegetation studies. The communities identified in the EPA are Willow carr (riparian), Ponderosa pine-oak and Ponderosa pine-Douglas fir-oak. Aerial photo interpretation of 1982 photos taken by Associated Surveys, Inc. suggest the "pre-mine" vegetation map is accurate for the Willow carr (riparian) community. The areal extent of the Ponderosa pine-oak is questionable. Topographically, it is unlikely the Ponderosa pine-oak extended to the river. Regardless, the Division found vegetation studies inadequate because a precision value of 0.2 instead of 0.1 was used to calculate sample adequacy. In addition, the Division found if the three (3) communities independently comprised less than 5 percent of the life-0f-mine disturbance, additional sampling would not be required. • There has been no disturbance in the Ponderosa pine-Douglas fir-oak community. Approximately 20 acres of Willow carr (riparian) area has been disturbed. Thus, the Willow carr (riparian) area comprises greater than 5 percent of the proposed life-of-mine disturbance. (The surface disturbance area as defined here includes the entire area delineated on Figure 1; seventy (70) acres south of Highway 12 and sixty-six (66) acres north of Highway 12 which includes the refuse disposal area.) As mapped in the 1981 study, the Ponderosa-pine-oak would also comprise more than 5 percent of the total life- of-mine disturbance. Interpretation of the 1982 aerial photos shows the only disturbance in this community to be 2.0 acres or 1 percent of the disturbance area. Sample adequacy was recalculated using the 1981 vegetation study data with a 0.1 precision level. Sample adequacy could not be obtained using this precision level. • -3-