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5. Page 37 of Volume 3 <br /> The 6 . 93 cfs. shown is in error it is supposed to <br /> represent the drainage of pad No. 3. The discharge for a 25 <br /> year storm for this pad is 0. 38 cfs.` - The error is in the <br /> area, it is supposed to be 0.44 acres not 10.61 acres, there <br /> is no additional drainage that comes to this pad. <br /> 6 . Mine effluent <br /> There is no mine effluent discharged into this pond. <br /> The mine discharge goes directly into the North Fork of <br /> Dutch Creek. <br /> Mine No. 3 <br /> 1 . Two ditches are involved in the drainage of this pad. <br /> See map II-B-App. 7-Att. 1, Exhibit 3-1 and 3-2. <br /> a. Drainage area 1 - Diversion ditch, north end of <br /> pad, drainage into pond 3-1. Dimensions; trapezoidel , 2 <br /> feet deep, 2 feet wide at bottom and 4 feet at top. Peak <br /> flow 4 . 0 cfs which leaves 1. 0 feet + of free board. <br /> b. Drainage area 2 - Diversion ditch or swale at the <br /> south edge of pad. Drainage into pond 3-2A, 3-2B. Dimen- <br /> sions; Swale across road, 1. 3 feet deep, 5 feet wide at <br /> bottom, 10 feet wide at top. Peak flow 6. 7 cfs, which <br /> leaves 0. 4 feet + of free board. <br /> 2. "6" CMP spillway gated" was not constructed as shown on <br /> Exhibit 3-2 , instead a 12" CMP ungated pipe was installed <br /> (7 ' + above bottom) . This gives an approximate detention <br /> time of 24 hours (See Volume III, pages 54 to 59) . ' <br /> This pond has never received more than 10% of its <br /> storage capacity even though the snowpack and rainfall have <br /> been above normal. It is believed that the solar radiation <br /> at 10, 000 ' increases evaporation rates all year around, <br /> especially in the winter when normally they would be very <br /> low. <br /> 3. The mine discharge is not run into this pond. It <br /> bypasses the pond, to outflow in the same general area. <br /> 4 . Small area exemptions (See Volume 7, Chapt. V, Page 2- <br /> 3) . <br /> a. No. 3 mine center bin and lower bin. These dis- <br /> turbed areas are less than two acres and there is no mixture <br /> of surface drainage with a discharge from underground workings. <br /> 5. Each of these ponds will be dewatered within 24 hours <br /> following any runoff event to maintain storage capacity for <br /> a 25 yr/24 hr precipitation event by pumping or syphoning. <br /> Mine No. 4 <br /> 1. Parent equation, Bernoullis for Orifices Q=Ca 2gh <br /> Handbook of Hydraulics by King and Brater, Chapt. 3, Pages 3 <br /> and 4 . <br /> 63 <br />