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of the probably hydrologic consequences of the proposed mining operation. Each year, <br />Deserado assesses the ongoing impacts to the hydrologic system in its annual hydrologic <br />report. The probable hydrologic consequences as set forth in Volume 1, Section ILC are <br />summarized below. The small area exemption sites are listed in Section IV.J.5 of the <br />permit application. Sedimentation demonstrations for small area exemptions are <br />provided in Illustration 44, of Volume 12, and the locations are shown on Map 147. <br />A. Water Quality Standards and Effluent Limitations <br />With the exception of approved small area exemptions, all discharges from the <br />Deserado Mine will pass through sediment ponds or treatment facilities designed <br />to ensure that all discharges meet applicable effluent limits under the operator's <br />Colorado Discharge Permit System (CDPS) permit. Any water pumped from <br />underground workings will be clarified by allowing sufficient settling time in <br />underground sumps, abandoned areas, or treatment ponds prior to discharge to the <br />surface. Approved mine water discharge sites have been inactive since the <br />northern portion of the "D" seam mining district was sealed off in 1996. In <br />January, 1997, the operator was granted approval to discharge preparation plant <br />thickener water within sealed sections of the "D" seam mine workings, pursuant <br />to the requirements of Rule 2.05.3(9). <br />A storm water permit and spill prevention containment and control plan <br />associated with the CDPS permit also dictate preventive and mitigation measures <br />for ensuring that all water leaving the mine site meets applicable effluent limits. <br />Due to facility site layout and sediment pond location, existing sediment ponds <br />which provide sediment control for the DB portal facilities will necessarily be <br />eliminated in conjunction with reclamation grading of the facility areas. <br />Alternative sediment treatment facilities to ensure discharge effluent limit <br />compliance for this location following reclamation grading will be necessary. <br />Similarly, existing small area exemption sediment controls for the East Portal <br />Ventilation facility area will be eliminated during reclamation grading, and <br />alternative measures will be necessary. A specific plan for controlling <br />sedimentation during and after reclamation grading has been provided for the DB <br />portal area, and a generalized post - grading sediment control plan has been <br />provided for the East Portal Area. A description is provided within Section V.13.6 <br />of the application to provide a more detailed post grading sediment control plan <br />and demonstration for the East Portal. <br />The Division has granted a number of small area exemptions (SAE'S) from the <br />use of sediment ponds and treatment facilities, due to the limited size of the areas <br />in question and due to the fact that ponds and treatment facilities are not necessary <br />for the drainage from these sites to meet the effluent limitations of Rule 4.05.2, <br />and applicable State and Federal water quality standards for receiving streams; <br />and also due to the fact that no mixing of surface drainage from these areas with a <br />discharge from underground workings will occur. The small areas to be <br />26 <br />