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Refuse fines will be recovered from the bottom of the thickener and pumped in a six inch <br />diameter poly -pipe to one of the refuse return wells. This line will be buried from one to <br />three feet below ground surface to prevent freezing and disturbance from surface operations. <br />Exposed portions of the pipe will be bermed to prevent runoff should a spill occur. The <br />refuse slurry will consist of a maximum 34 percent solids by weight and water will be used <br />as the transport medium. The slurry will flow down through the return wells into the <br />abandoned workings and disperse. Return water will be recovered by a pump located north <br />of the preparation plant and piped to the plant for reuse. Slurry will be pumped at a <br />maximum rate of 700 gallons per minute with return water being pumped at the comparable <br />liquid percentage to allow for makeup water in the plant. The existing belt press system will <br />be retained in the preparation plant for additional backup in the event that the system is out <br />of service. <br />Areas to be backfilled will be sequenced from east to west (down dip to up dip). The refuse <br />return wells are located over an Allen Seam panel that has been pillared. Solid barrier <br />pillars will isolate new workings in the Allen Seam from the flooded fine refuse disposal <br />areas. The operation is not anticipated to change the existing condition of the mine and will <br />not have an effect on the surface area supported by the mine or surface effects following <br />backfilling. <br />The source of hydraulic transport medium for the slurry will be the makeup water pumped to <br />the prep plant which will be obtained from the existing mine pool in the underground <br />workings. Probing the clean water recycling hole (NEW -4) has indicated that approximately <br />50 feet of water is available in that area of the mine pool for return to the prep plant. Initial <br />makeup water will be the water already in the Prep Plant obtained from the Purgatoire River <br />from the Applicant's existing water rights. The method to be used to dewater the refuse fines <br />is to pump the water back to the Prep Plant from New -4. <br />Hydrologic impacts and monitoring are described under Section 2.05.6. <br />MR -95 2.05 -44b Revised 08/24/11 <br />