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L ponds to achieve the detention time. Cross-sections of these are shown on Drawings D-4-5 and D-4-6. An emergency Spillway is provided for each pond, as shown on the above-mentioned drawings. The spillway is a trapezoidal earth structure with 2:1 side slopes, ~ designed to safely discharge the runoff from a 25-year, 24-hour precipitation event. The minimum design freeboard is 1.2 feet in Pond P-3 and 1.4 feet in Pond P-9. To minimize impacts to the stream during reclamation, all reclamation activities will be scheduled in such a way as to minimize soil disturbance and erosion. Activities will begin after peak runoff has occurred. It is during runoff that most erosion does occur, In certain areas, grading and/or backfilling will be used to decrease the slope and aid in the establishment of vegetation. • Final reclamation will begin upon cessation of operations. During reclamation, ditches 2, 5, 4, 8 and 11, sedimentation ponds 1, 3, 4, 9, and the refuse disposal ponds will remain intact. These ditches will collect runoff from all disturbed areas during reclamation and pass the runoff through a sediment pond, The above ditches and ponds will remain intact until agency approves that disturbed areas are reclaimed according to revegetation criteria of Section 4.15.7. Upon the agency approval of these criteria, the ditches and sediment ponds will be reclaimed. In addition to the ditches and ponds, special surface treatments, such as contour furrowing, pitting, water bars or other methods, will be used for increased stability and moisture retention. At this time, no instream sediment control measures are anticipated. Water quality will not be impacted by suspended solids during reclamation or after a large precipitation event. As stated in Appendix 4-B, the peak discharge from Ponds 3, 9, and the refuse pond, following a 10-year, 24-hour design storm, will be a total of 0.90 cfs. The small flow rate is due to the 24-hour detention time. 4-105