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<br />The proposed mitigation plan states that following mining and lining of the water storage <br />reservoir, the applicant will continue to monitor groundwater levels in the area of the <br />water ski club pond. The applicant will need to clarify the frequency and duration that <br />the water level in the pond will be monitored. It is also unclear if the applicant proposes <br />to monitor the pond before and during the mining activity. The applicant will need to <br />commit to obtaining baseline water levels of the water ski pond and a monitoring <br />frequency for both during and after mining. It would also be helpful if there are any <br />historical water levels of the water ski pond to determine a baseline level. <br />In the immediate area of the mine, groundwater has a saturated thickness of only 10 to <br />20 feet, in very permeable soils. The site is located less than 0.5 miles from the open <br />channel of the South Platte River in an area where groundwater will demonstrate a high <br />hydraulic conductivity. Seasonal effects, the effects of other mining activity, irrigation, <br />and other well usage are additional reasons why precise local groundwater elevations <br />can be a moving target. <br />Because mining in this historic pit is proposed to begin and be completed within the next <br />two years, and because of the difficulty in defining historic groundwater levels in a <br />specific location near the mine, meaningful baseline water level data for the immediate <br />area of the mine will be difficult to develop. The applicant is thus proposing to install <br />three monitoring wells in the area of the water ski pond as shown on the attached <br />drawing. Comparison of relative water levels in the water ski pond with those in the <br />monitoring wells will provide a measure of the impacts of dewatering activity. <br />Monitoring wells will be installed before dewatering begins. Groundwater elevation in <br />the monitoring wells and in the water ski pond will be measured at least monthly <br />thereafter, through mining and reclamation activity. Exceptions to this schedule will <br />occur during the irrigation season of May through September, when water elevations will <br />be determined at least every other week. Following completion of reclamation steps, <br />water levels will be monitored on a quarterly basis for five quarters (15 months). <br />One of three monitoring wells will be placed along the southern boundary of the Ski <br />Club's property. A second is proposed for property immediately south of the mine, and <br />the third is proposed for property north of the mine and 124'" Avenue. Agreements with <br />landowners to place monitoring wells on property north and south of the mine have not <br />been finalized at this time; however, the applicant is comfortable that such agreements <br />can be finalized. <br />• The applicant proposes a piezometer to be placed south of the ski club and south west <br />of the reservoir. Please indicate the location of these piezometers on map, and specify <br />the frequency and duration in which they will be monitored. <br />(For the sake of this application, the words 'piezometer' and 'monitoring well' have been <br />used interchangeably by Banks and Gesso, LLC. Our intended meaning is a monitoring <br />well for determining groundwater elevation.) The monitoring wells will be installed in the <br />approximate locations shown by the accompanying drawing; and the proposed <br />monitoring schedule will be as stated above. <br />• The applicant states that if the Water Ski Club's pond surface decreases by more than 2 <br />/eet from the expected seasonal elevation, the applicant will take mitigative measures <br />mutually agreed to by the water ski club and the applicant. Please explain the rationale <br />