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<br />northwest and downgradient of the mining area. In addition, local groundwater is exposed <br />within the pond of the Henderson Water Ski Club, approximately 500 feet west of the <br />proposed mining area; and there are likely several unpermitted, shallow wells, used for <br />non-domestic needs of the residences along 124'" Avenue, north of the proposed mining <br />area. <br />The Applicant acknowledges that shallow wells along 124'h Avenue and the pond of the <br />water ski club will likely be impacted by dewatering of the mine site. This pond, the one <br />permitted well, and any unpermitted, shallow wells are generally downgradient and within <br />a quarter mile of the site. The unconsolidated alluvium of the area is relatively permeable, <br />and the groundwater has a saturated thickness of 10 to 20 feet. <br />Because this mining and reclamation project will start and finish in an approximate 2.5 <br />year period, and because placement of a clay liner will occur concurrently with mining, any <br />impacts to groundwater will be short lived. The Applicant is proposing a mitigation plan to <br />include the following steps: <br />When permitted or non-permitted, shallow wells along 124'" Avenue show <br />decreased capacity, unsatisfactory to the landowner, the Applicant will pay the <br />landowners water bill from the South Adams County Water and Sanitation District <br />from that time through completion of mine reclamation steps. It is the Applicant's <br />understanding that all landowners with non-permitted wells along 124`" Avenue <br />between State Hwy 85 and the Fulton Ditch are also connected to the District. For <br />most of these landowners, connection to the District's water supply occurred when <br />contamination of shallow groundwater, originating from the Rocky Mountain <br />Arsenal, was discovered to have reached this area. By paying water bills, the <br />Applicant will be directly compensating the well users for any losses due to <br />decreased well capacity. <br />The Applicant will place $10,000 in escrow before mining is initiated to pay for <br />rehabilitation of shallow wells along 124'" Avenue that lose efficiency during mine <br />dewatering activities. <br />Dewatering facilities from the mine will be designed to allow discharge to the Fulton <br />Ditch or directly to the Henderson Water Ski Club. Discharge to the Water Ski <br />Club and maintenance of the water level in its pond will have the effect of <br />recharging groundwater immediately downgradient of the mine. <br />Following mining and lining of the water storage reservoir, the Applicant will <br />continue to monitor groundwater levels in the pond of the water ski club to ensure <br />that the lined reservoir will not have a damming effect on groundwater and cause <br />significantly lower groundwater elevation in the pond of the Water Ski Club. Water <br />level in the pond of the Ski Club will be compared with the local groundwater <br />elevation, as measured by a peizometer to be placed south of the ski club and <br />south and west of the reservoir. A lower elevation of groundwater in the pond as <br />compared to that measured by peizometer will be interpreted as attributable to a <br />damming effect of the reservoir. The peizometer will be installed when mining <br />activity is initiated so that groundwater elevations can be recorded on a regular <br />basis, and a relationship between pond level and groundwater level, as measured <br />by peizometer, can be established. If the Water Ski Club's pond surface <br />decreases by more than 2 feet from the expected seasonal elevation, the Applicant <br />will take mitigative measures mutually agreed to by the Henderson Water Ski Club <br />and the Applicant. Such measures could include the installation of a french drain <br />