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• observed at depths greater than 25 feet. In one well, ground water was observed within <br />the Mancos Shale and in the second well as a thin perched zone on top of the shale. <br />There is no evidence of historical irrigation or other agricultural use of any landforms <br />within the study area, with the exception of limited grazing. The former alluvial fans <br />have been dissected and isolated by the downcutting streams and only receive water from <br />precipitation. The fans currently support stands of pinyon and juniper. All other areas <br />within the study boundary are too steep and do not have soils suitable for agriculture, <br />with the exception of grazing (Soil Survey of Mesa County, Colorado [USDA, SCS, Feb. <br />1978]). <br />Proposed Water Handling <br />Because of the lack of local water sources, Red Cliff Mine proposes to pump <br />approximately 700 acre-feet per year (- 1 cfs) from Mack Wash, located approximately <br />15 miles south-southwest, to the study area. Water will be stored in a 0.5 million gallon <br />tank located above the mine portal and will be used for dust suppression, fire fighting, <br />. domestic (office and sanitary), and coal washing. Red Cliff does not anticipate there will <br />be any discharge of excess water from this source, other than limited water used for <br />domestic purposes. Domestic water will be treated onsite in a package sewage treatment <br />plant and the effluent discharged to the nearest drainage. Runoff from precipitation will <br />be directed to sedimentation ponds located below various facilities, such as the waste <br />rock pile. After settling suspended sediment, runoff will be discharged to the nearest <br />drainage. Other than minor losses due to evaporation, this water does not represent any <br />change to the existing hydrologic system. <br />After several years of mining, Red Cliff anticipates that the mine will encounter saturated <br />conditions, which will require pumping from the mine. A third party contractor <br />performed a hydrologic analysis of the likely mine inflow rates for the Environmental <br />Impact Statement (EIS) using a ground water model calibrated to mine inflows measured <br />in the nearby McClane Canyon Mine. The analysis indicated that the likely mine inflow <br />rate for the Red Cliff Mine would be about 10 to 40 gpm and would average about 50 <br />• gpm, should pumping stop at the McClane Canyon Mine. The AVF analysis assumes all <br />ERO Resources Corp. <br />AVF Determination - Red Cliff Mine <br />Page 3 <br />6/19/2008