2016-02-03_PERMIT FILE - C1981038 (2)

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42.04 APPLICATION FOR PERMIT FOR SURFACE OR UNDERGROUND MINING ACTIVITIES -- MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES. 2.04.7 Hydrology Description. (1) (b) (Cont'd.) water presence during the exploration drilling, water level measurement during the geophysical well logging, and water level measurements in the monitoring wells. The results of this interpretation are shown on Map No. 10-1. This map shows, in a form of a fence diagram, the perched water bearing strata below the "D" coal seam and the principal saturated strata above the Rol- lins Sandstone. The main saturated strata is typically 120 to 160 ft. below the "D" coal seam. Several moni- toring wells in the western part of the permit area (DH-68, DH-65, and DH-60) indicated water levels above the "D" coal seam; however, this could be caused by wa- ter inflow from the perched zones or from the colluvial sediments. The interpretation of the potentiometric surface in the main saturated strata above the Rollins Sandstone is presented on Map No, 4-2, This interpre- tation indicates that the recharge area into this aqui- fer is near the outcrop of the sandstone strata and in ' the parts of the sandstone subcropping underneath the • local streams in particular. The general groundwater flow in the Mesaverde aquifer is toward north, follow- ing the basin structure. Only one spring in the study area is considered to be issuing water from the bedrock. The spring denominated as No. 25 is located in NE 1/4, NW 1/4, Sec,19, T.13S., R.91W., in an unnamed drainage between the Orchard Val- ley and the Farmer's Mines. This spring is located on a well-pronounced fault crossing the existing mine in a northwest- southeast direction. This fault has a ver- tical displacement of up to 50 ft ., as measured in the mine. IL seems that this spring is related to a perched water bearing sandstone above the "D" coal seam. Discharge from this spring is very low during the summer and a maximum discharge rate was estimated at 2.7 gpm. The water quality of this spring is dis- tinctly different from the other monitored springs in the lease area. The total dissolved solids in Spring 4125 ranged between 2200 and 2360 mg/1, while the TDS of the other springs are typically below 1000 mg/1. Groundwater issuing from this spring is of sodium sul- fate-bicarbonate type. Added 02/26/85 Revised 10/01/87 36