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• SURFACE WATER HYDROLOGY <br />The CEC site drainage plan and the associated structures are discussed in Appendix <br />K of the Permit, and can also be found in Technical Revision #28 (2/95), "Drainage <br />Control Plan II". During reclamation, the diversion ditches, drainage ditches, and <br />drainage swales that have been constructed along the roads, and azound the north <br />and east sides of the CEC property. These features serve to convey any surface <br />water runoff to Sediment Pond 2. The present drainage facilities, as well as existing <br />site topographic features, aze shown on the Existing Surface Features and Utilities <br />Map (see page 130). Certain surface water control features have been designated as <br />permanent facilities (by Permit revision, and at the direction of CDMG and others). <br />These features will remain following the completion of all site reclamation <br />activities. The permanent facilities include: <br />• Sediment Pond #2 <br />• The East and the West Perimeter Ditches <br />• The Dugout Pond <br />These permanent drainage features are identified on the Reclamation Contour and <br />Drainage Plan Map (see page 131). <br />. With the exception of Sediment Pond 2 and the Dugout Pond, all previously <br />existing man-made temporary pond sites have been closed, and subsequently <br />deleted from the drainage control mapping and monitoring requirement. This <br />action was considered appropriate because: 1) the sedimentation infill of Sediment <br />Pond 2 has been virtually non-existent after more than fifteen yeazs of continuous <br />use, 2) Sediment Pond 2 has not had significant amounts of water stored in it for <br />more than brief periods (except during the unusual and prolonged periods of excess <br />precipitation in 1995 and 1999), and 3) even considering those unusual events of <br />1995 and 1999, to date there has not been an observed discharge from Sediment <br />Pond 2. <br />CEC also implemented a dewatering scheme for Sediment Pond 2 in 1997, in <br />conjunction with the prepazation of a,"Spill Prevention, Control and <br />Countermeasures Plan" for the site. When conditions warrant, CEC personnel will <br />pump the excess runoff water accumulated in this pond back to the Dugout Pond <br />which is located about 700 feet slightly upgradient and to the south-southeast on <br />CEC property. The Dugout Pond has an available storage capacity exceeding the <br />total contributing runoff volume associated with a 100-yeaz, 24-hour design storm <br />• event (refer to "Technical Revision Drainage Control Plan II," dated January, <br />1995). A series of pumps can be employed, as needed, to evacuate the accumulated <br />AHR-2003 -s2- <br />