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a <br />Dan Mathews • -2- ~ugust 30, 1933 <br />photo, is 2.16 acre-feet of water, compared to the designed 2.61 <br />acre-feet (page G-9, permit #77-232). This volume was calculated <br />using a 2.4" storm event. Closer interpolation from the tables <br />gives 2.2" of rainfall, as used in our present permit application, <br />File #C-034-31. This revised storm event requires a water storage <br />volume of 2.27 acre-feet, or 5% more than actual. <br />Due to the water in the pond, an accurate calculation of the <br />sediment volume cannot be made from the air photo. An adequate esti- <br />mate of the available sediment volume is 0.9 acre-feet, compared to <br />a design of 1.38 acre-feet. This volume is 65°~ of the design volume, <br />which is good for three years' sediment load. <br />Except for the actual water volume, this pond has been installed <br />according to the approved design in our #77-232 permit. Considering a <br />5% error in volume when using the 2.2" rainfall event and the high <br />likelihood of the dam's removal in the next one to five years, I feel <br />that the volume is adequate to justify certification of the sediment <br />pond. <br />Observation of the sediment pond for deterioration and sediment <br />loading will continue on a regular basis. A quarterly report will be <br />submitted to the Division, noting these observations. <br />If there are any further questions, please feel flee to contact <br />me. <br />Very truly yours, <br />Larr~M. Reschke, P.E. <br />Mine Engineer <br />/969/ <br />LF1R: KES <br />9-i-£~3 <br />