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NOV-09-2001 FRI 08:41 AM BANK~ND GESSO LLC FAX N0. 3034 8329 P, 06 fora 2-loot drop in water level to initiate a mitigation plan, and is this water level drop agreeable to the Water Ski Club. In order to implement this plan, the applicant will need to provide to the Division the seasonal elevations of the water ski lake. Please address accordingly. USGS studies indicate that, in the area of the water ski club, unconsolidated groundwater has a saturated thickness of 10 to 20 feet. The ski club states that water depths in its pond are generally between 10 and 40 feet except in the westernmost 5 e o , w ere water ep is eat or less. A 2 toot decrease thus represents a 5 to 20 percent change in most of the 23 acre pond and was selected initially as a trigger for mitigative steps, because any smaller deviation will be very difficult to discern, in light of the several factors contributing to fluctuating groundwater elevations - permeahle soils, high hydraulic conductivity, seasonal effects, effects of other mining, irrigation, and well usage in the area. In discussions with the Water Ski Club, the applicant has subsequently agreed to a 0.5 foot decrease in pond surface Tom Krueger; the Ski Club Manager, reports that at least one Glub member desves mitigative steps to occur, when something less than a 0.5 foot decrease is noted. The Water Ski Club has not suggested a method for discerning when such a decrease would be attributable to mining activity. As stated, water levels in the water ski pond will be All groundwater monitoring data will be summarized and submitted to the Division on a quarterly basis, beginning at the time that monitoring begins and ending when monitoring is discontinued, fifteen months after reclamation has been completed. • The applicant will need to commit to submitting one of the specific mitigation plans mentioned in the form of a technical revision to the permit in the event such measures are required for mitigation of the groundwater wells and/or water ski pond. The comment is acknowledged. And, based on recent discussions with the Water Ski Club, the applicant would like to add another possible mitigative means to the previously mentioned alternatives for responding to decreasing ski pond levels - to add water to the ski pond from sources other than the water storage reservoir, which are_of_acceptabls: . The applicant proposed an interim mitigation plan for impacts to the surrounding wells. Please explain if there are any long-term mitigation plans addressing impacts to the surrounding wells. Because of high permeability and hydraulic conductivity of local soils, the applicant believes that groundwater will rapidly re-attain its current elevations. Only in the immediate area downgradient of the mine is a shadow of, perhaps, a one foot loss in ground water elevation expected to linger for a year or two following completion of the liner. Worst case effects will be seen during and immediately following dewatering activity, and current conditions will be re-attained relatively quickly thereafter. Thus, the applicant is not proposing long term mitigation steps. If replacement water is necessary