GENERAL46377 - Laserfiche WebLink

Home Browse Search

The total mine inflows presently encountered are insignificant and are insufficient to meet the water requirements of the underground mine. The Orchard Valley mine imports approximately 8-10 million gallons of water to meet these recuirements. If, however, the prediction of insigaifant inflows to the mice fails for whatever reasons, and it becomes necessary to discharge water from the mine, the applicant has prepared a proposed mine discharge plan. Prior to any discharge of mine water into or out of any sedimentation ponds, if this should ever become necessary, approval would have to be granted by the appropriate regulatory agencies. The withdrawal of the ground water from the Steven's Gulch well field depletes flows is this stream. This depletion of floe, flow which Could eventually reach the North Fork and benefit downstream water rights, has bees mitigated by the applicant via an approved augmentation plan decreed is the Division 4 Hater Court. Augmentation is accomplished by releasing water from a water right held is East Beckwith No.l Reservoir, located in the Anthracite drainage. The applicant has submitted records of water withdrawals and water chemistry data on the Steven's Gulch well field. The applicant has furnished this data in monitoring submittals since the issuance of the original permit. The applicant may impact ground water quality below the coal processing waste pile. To monitor this impact to ground water, the applicant has installed and is monitoring a well. To date the data has not shown that leachate from the waste pile is contributing to stream flow. Rowever, as the pile increases, the potential for leachate increases. Therefore, CHI will continue to monitor • the well below the pond to identify any impacts. The Orchard Valley mine plan is designed to minimize the impacts of the project on the surface water hydrology of the region. Disturbed area drainage from the mine benches, parking area, and loadout site is collected and treated on the site. The mine operator has obtained the appropriate NPDES permits. Effluent quality from sedimentation ponds will be monitored to determine permit compliance. Runoff from the waste disposal sites is routed through the sediment control system and must meet effluent limitations. Subsidence effects have the potential to impact any or all springs, seeps, and ponds within the affected permit area. Rowever, CHI has been unable to obtain sufficient data to support this prediction. In order to protect water resources, but still allow mining, CWI has developed a mining plan that minimizes impacts, subsidence repair procedures, and a water replacement plan. • 6