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All of the water that leaves the mine comes out in the 50 mesh size mud from the marble cutting or the <br />drainage pipe extending from the south portal. This material is left to dry near the South Portal as shown <br />on Map C-2. The water from the dewatering is collected in a sump and pumped to a 6" pipe located on <br />the surface leading to Yule Creek, where the discharge is sampled as part of the NPDES permit. This <br />system will be maintained for the post 2010 operation. As described in the Sediment Control Plan, 5 <br />new sumps will be created to provide water detention and each of these sumps will be a new outfall in <br />the revised NPDES permit. Therefore, there will be 6 total outfalls in this permit. <br />Since all the water used in the operation has entered the mine from groundwater cracks, no surface water <br />consumptive use exists. All water placed with the cutting mud on the mud drying area is either <br />evaporated or placed in Yule Creek from the pumping operation. <br />3. Hydrologic Impacts and Sediment Control Plan <br />The marble mined at this quarry is basically calcium carbonate, which is a basic material, and will in no <br />way produce acid runoff. The marble could actually improve the quality of natural runoff. The biggest <br />potential negative impact from the operation is the disposal of fine material in the dump areas, which <br />could make their way down to the drainage below and result in higher suspended sediment loads in a <br />very clear stream (Yule Creek). <br />For this reason, the sediment control system has been completely redesigned for the 2010 Amendment to <br />address the fines issue and detention of runoff for all mine site disturbances. Since there is no room on <br />the site for a large sediment detention structure, the Yule Quarry mine area has been divided into five <br />drainage basins that will each direct run-off towards a sump. The calculations for the total run-off in <br />each basin can be seen below, and the basins themselves can be seen on Map C-2. Additionally, several <br />collection ditches will have to be installed in order to gather and direct run-off to the sediment sumps. <br />The designs for these ditches are found below in this section as well. <br />The main sources of potential sediment on site are fines from the cutting of marble blocks from <br />underground. The fines mixed in with water during the cutting process, and pumped out of the mine as <br />Yule Quarry April 10 17