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alfalfa. The two shrubs aze big sagebrush and rubber rabbitbrush. Species <br />diversity is deemed successful. <br />Greystone has done some minor rill and gully repair during the past couple of <br />years. The repairs have been limited in extent and aze compatible with standard <br />husbandry practices undertaken in well managed range lands. All areas where <br />repairs were made were included within the random vegetation sampling aeeas. <br />Slurco Corporation's statement of probable hydrologic consequences is found in <br />the permit application, Volume I starting on page 72. Their data indicated that <br />mining should not cause any significant impact to the quantity or quality of either <br />surface or ground water. The limited area of mining disturbance relative to both <br />the Bolton Draw watershed as well as the total azea of rechazge of the Coalmont <br />Formation would be small in comparison to the total area of recharge. Any <br />effects were predicted to be localized in nature and would result primarily in the <br />decrease of water availability to both the surface water and groundwater systems. <br />Hydrologic monitoring data was collected beginning in 1980. In 1990, <br />hydrologic monitoring was reduced to collecting water level in one spoils well <br />and analyzing a full suite of parameters from grab samples of the pond water. <br />Appendix B of the bond release application contains the operators 1997 Annual <br />Hydrologic Report. <br />Bolton Draw, an ephemeral drainage in the mine azea that flows primarily in the <br />spring from snowmelt and in response to precipitation events, is the only <br />receiving stream for water leaving the Canadian Strip Mine. The probable <br />hydrologic consequences were anticipated to be limited to a change in the timing <br />of stream flow and minor changes in water quality because of the sediment ponds <br />located on the mine site. Data shows impacts to Bolton Draw have been minimal. <br />There has been no discharge from either of the permanent ponds for several years. <br />Water retained in the ponds is slightly reducing the flow that would otherwise go <br />into the Draw however, the mine site is only 80 acres which is less than 2% of the <br />total flow to Bolton Draw. The predictions made in the statement of probable <br />hydrologic consequences have been confirmed. The impacts to the surface water <br />flow are negligible and counteracted by the increase in available water to <br />livestock and wildlife due to the retention of two ponds. <br />Surface water quality effects due to mining were predicted to have a potential for <br />increased salt loading. However, the extent of mining was decreased from that <br />originally proposed. The pumpage of pit water with elevated total dissolved <br />solids (TDS) concentrations relative to surface water levels did not occur as <br />proposed. With the establishment of vegetation on the disturbed mine site, the <br />effects of surface water quality are considered negligible. <br />Water quality in the permanent ponds is calcium bicarbonate with slightly saline <br />total dissolved solids concentrations ranging from 145 mg/l to 360 mg/l. This is <br />comparable to premining surface water quality. Using standards se[ by the <br />Canadian Strip Mine 5 November I8, 1998 <br />Permit No. C-81-026 Final Bond Release <br />