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• Pond #1's principal spillway (Figure 2) was not constructed <br />exactly as was originally approved; however as shown by Figure 2, <br />the constructed spillway should more effectively accomplish its <br />function by being more accessible for manual water level control. <br />The elevation of the drop inlet has been adjusted to the 8199 ft <br />elevation. All design criteria for Pond #i are found in Appendix <br />Q• <br />The adjustable weir shown on the principal spillway of Pond <br />#1 (Figure Q-2) allows the water level to be manually adjusted. <br />There will at all times be sufficient capacity to collect and treat <br />the 4.14 acre-ft runoff from a 10-year, 24-hour storm. <br />The peak flow rate for the 25-year event into Pond #1 has <br />been estimated to be 72.64 cfs. The peak discharge for the 25-year <br />event through the emergency spillway will be 6.4 cfs. If the <br />primary spillway is inoperative, the discharge over the emergency <br />• spillway is 15.41 cfs. Thus, the combined capacities of the <br />principal and emergency spillway are more than adequate to handle <br />the 25-year 24-hour storm event. <br />The top of Pond #i dam embankment was constructed at an <br />elevation of 8202.2 to allow for 0.5 ft (5%) of settlement and is <br />at least 1 ft higher than the emergency spillway. The emergency <br />spillway was constructed at least 1.0 ft above the principal <br />spillway, as shown on Figure 2. <br />The top width of Pond #1 is at least 8 feet wide. <br />Sedimentation Ponds #2 and #3 were constructed during the <br />fall of 1980, and, although quite small, were required to collect <br />any sediments and water running off the south extension of Pit #1. <br />During the 1987 reclamation of Pit #1, Pond #2 was replaced with a <br />larger pond located in the reclaimed area. All design criteria and <br />• - 3 8 - Revised 77/29/94 <br />