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slopes and cuts as necessary for reclamation. Exterior slopes of sedimentation ponds at the main <br />mine facilities were reclaimed with a fast growing vegetative cover after they were constructed in <br />order to prevent excessive erosion of the embankments. <br />The cross section of each sedimentation pond is given in Exhibit 66. Sedimentation pond designs <br />aze provided in Exhibit 42, Exhibit 43, Exhibit 44, Exhibit 46, Exhibit 47 and Exhibit 66. An <br />emergency spillway has been provided for each pond, which will safely pass the peak runoff from a <br />precipitation event with a 25-year recurrence interval or lazger (100-year for MB-1 and MB-2R). <br />The RPE pond has been designed to completely contain the runoff from a 100-yeaz, 24-hour storm <br />event. Designs for the RPE pond aze located in Exhibit 70. <br />Small area exemption (SAE) demonstrations for the azeas shown on Map 54, Map 54A, and Map <br />54B aze provided in Exhibit 66. Dischazges will meet State and Federal water quality requirements. <br />No mixing with underground mine water occurs in these azeas. Based on professional judgement, <br />Mountain Coal Company believes that applicable effluent limitations will not be exceeded. <br />Periodically, MCC will review the conditions of best management practices recommended by the <br />small azea exemption demonstrations and ensure they are functioning. <br />The specific size and capacity of any particular sedimentation pond aze presented on Map 54 and <br />Map 54B and aze summarized in Exhibit 66. Stability analyses aze presented in Exhibit 44. Exhibit <br />45 shows the approval by the Chief of Dam Safety, Division of Water Resources, of Ponds MB-1 <br />and FW-1. Pond MB-2 has been redesigned and replaced by pond MB-2R. <br />The design for the fresh water pond is shown in Exhibit 43 and in Exhibit 44, Design Report. The <br />fresh water pond FW-1 at the West Elk Mine is approximately 10 acre-feet in capacity. The <br />proposed fresh water pond FW-2 is also about 10 acre feet in capacity. <br />FW-1 stores water which is pumped from the North Fork of the Gunnison River. FW-1 supplies <br />raw water for potable use, dust suppression, and the fire suppression system. FW-1 was constructed <br />from suitable site materials and is an engineered earth-fill embankrnent with 3H to 1V sideslopes. <br />The pond is lined with asemi-impermeable clay liner. Pond FW-1 specifications aze contained in <br />Exhibit 49. Exhibit 44 contains design considerations and data. <br />FW-2 has not been constructed at this time, and is not planned for this five yeaz pernut term. FW-2 <br />is similar in constmcfion to FW-1. The location of FW-2 is shown in Exhibit 43. The design of <br />FW-2 is contained in Exhibit 44. <br />(5) Topsoil <br />Whenever technically feasible, topsoil and subsoil on sites of proposed surface facilities will be <br />stripped and placed in appropriate stockpiles before any construction occurs. Map 53, Map 53A, <br />2.05-39 Revised Jan 1997 TR79 <br />