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A conveyor runs north from the preparation plant approximately <br />3000' to a valley fill refuse pile which is actively under <br />construction. <br />Hydrologic consequences of the mine are attributable to <br />consumption of water to run the preparation plant, surface <br />disturbances at the site, and recharge of water into the mine <br />workings. The preparation plant uses water acquired from the <br />Middle Fork of the Purgatoire and typically utilizes 20.1 gallons <br />of water per raw ton. Surface disturbances at the facilities area <br />and coal shipping operations will result in an increase in total <br />suspended solids (TSS), which will be treated by sedimentation <br />ponds prior to discharge to the Middle Fork of the Purgatoire <br />River. A large proportion of the disturbed acreage is associated <br />with refuse deposits. Coal mine refuse at the site has been <br />backfilled into a short stretch of the river channel, and the river <br />is permanently diverted to the north in this reach. There are two <br />mine refuse piles: a small coal development waste pile located <br />north of the Middle Fork of the Purgatoire and a substantially <br />larger fill for waste from the processing plant located north of <br />Highway 12. These refuse piles will affect the water in alluvium <br />immediately adjacent to the waste piles. The area overlying the <br />• mine workings has the potential to subside further. This may <br />result in changes in channel geomorphology or impact the flow of <br />seeps or springs. Lastly, natural mine inflows are flooding the <br />mine workings. In 1994, Basin permitted the recycling of thickener <br />water from the preparation plant through the mine at a rate of 220 <br />gpm/8 hour shift/262 days/year. This has the potential to modify <br />the quality of the water in the workings, and to increase the rate <br />at which the mine floods and the potentiometric surface is re- <br />established. It will also simultaneously reduce the potential for <br />further subsidence in areas filled by the coal fines. <br />Water Consumption. Water from the Purgatoire River is <br />used at the coal preparation plant and for bath water at the New <br />Elk Mine. Water consumption is dependent on production rates and <br />employment levels. The preparation plant uses a closed circuit <br />design to recover and re-use water in the benefaction process. <br />However some moisture is lost both to the clean coal and refuse. <br />The preparation plant has the potential to <br />~J <br />2.05-59 (revised 12/18/98) ~A/~3 <br />'V 3'q q <br />