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Volume 1, Section II.0 of the Deserado Mine permit application includes an <br />assessment of the probable hydrologic consequences of the proposed mining operation. <br />Each year, Deserado assesses the ongoing impacts to the hydrologic system in its <br />annual hydrologic report. The probable hydrologic consequences as set forth in <br />Volume 1, Section II.0 are summarized below. The small area exemption sites are <br />listed in Section IV.J.5 of the permit application. Sedimentation demonstrations for <br />small area exemptions are provided in Illustration 44, of Volume 12, and the locations <br />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 January <br />1997, the operator was granted approval to discharge preparation plant thickener <br />water within sealed sections of the D seam mine workings, pursuant to the <br />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 from the use of <br />sediment ponds and treatment facilities, due to the limited size of the areas in <br />question and the fact that ponds and treatment facilities are not necessary for the <br />drainage from these sites to meet the effluent limitations of Rule 4.05.2 and <br />29 <br />