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sufficient to address the replacement needs for the Heit operation. Since no augmentation will be required once the slurry wall is completed and all groundwater pumped out, there is no need for any long-term augmentation These numbers are approximate in nature and are subject to possible changes once the Temporary Substitute Supply Plan is submitted for review to the Division of Water Resources. 14. The Applicant had a groundwater analysis performed for the site by Wright Water Engineers (WWE). The study is attached for your reference. We feel the study adequately addresses the Divisions concerns as outlined in numbers 14 through 16 of your letter. In general, the Applicant commits to installing monitoring wells around the perimeter of the site and also utilizing data obtained from private wells surrounding the site for which the owners would allow monitoring to occur. A baseline groundwater level could then be determined after a 5-quarter monitoring regime. The monitoring will begin in the third quarter of 2003 and the Applicant commits to not beginning dewatering operations until the 5-quarters of data is ~. obtained. The trigger point would be if groundwater levels in the area dropped more tha eve-feeYbel~y the normal seasonal fluctuations in the area, in which -- case the Applicant 6utd cease dewateri do h time that a cause of the drop could be determined. If the cause is determine o be the Applicant's mining operation, mitigation effo will be discussed at that time and decisions made will be based on which mitigation measure best serves all parties involved. Some mitigation measures that could be employed would be re-drilling wells, diverting available water supplies to the injured party, and/or trucking water to the injured party. Since the time of the a lication submittal, the Applicant has also committed to installin tea- nch Drain system along the southern and western sides of the property o ive r towards the north and east and around the property. This will help minimize the mounding and shadow effects even further. 15. It is likely that groundwater will be affected by the mine. However, we feel that any affect will be negligible. Based on the results of the WWE study it appears that a two to three foot draw-down affect may occur on the down-gradient (northern and eastern) sides of the mine area once the slurry wall has been installed. Similarly, on the up-gradient (southern and western) a one to two foot ' mounding affect may occur. The two to three foot draw-down would be characteristic at the mine boundaries, with less draw-down as distance from the slurry wall increases. For instance, at a distance of 50 feet from the slurry wall, the draw-down will be significantly less than the two to three feet at the slurry wall. For this reason, we feel that the cone of depression from the drawdown affect would be minimal and cause no harm to adjacent groundwater wells. Monitoring, trigger points and possible mitigation are discussed in #14 above. An illustration showing the predicted extent of drawdown and mounding affects can be found in Figure 3 of the WWE study. 16. The shadow effect of the slurry wall should have absolutely no impact on the structural integrity of any wells, drainages, or other activities that rely on groundwater, including the wetlands around Little Dry Creek. According to data from the Office of the State Engineer, the average groundwater well within 600' of the mine limits is drilled to a depth of 30 feet. The average static water level in these wells is 6 feet below ground level. A draw-down of 2-3 feet at the slurry