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Reach 1 is 3.8 fps. These peak velocities are below the maximum allowable velocity of 5 <br />fps for the vegetative cover lining. <br />gtnrk Pnnrlc <br />In order to assure compliance with effluent requirements at the outlet of Prospect Pond, <br />up to 5 stock tanks have been constructed near the re- established main drainage channels <br />of Prospect Ditch, North Tributary East Pit Ditch, and Final East Pit Ditch. Three of <br />these (PD -1, PD -2, and NTEP -1) were constructed in 2010, one in 2011 (EP -1). The <br />other stock pond (EP -2) was constructed in 2012. <br />For all stock ponds PD -1, PD -2, NTEP -1, EP -1, and EP -2, actual as -built surveys of <br />volume v.s. elevation were used in the SEDCAD model. For simplicity of design and <br />operation, and as a conservative consideration, all ponds were assumed to be brim -full at <br />the start of the precipitation event, thereby minimizing their flow attenuating effect on the <br />runoff in the design storm. <br />Reclamation Time Frame Evaluated <br />Although three distinct reclamation time frames were required for the sediment pond <br />modeling presented separately in Exh. 7 -14PP, only the 2017 time frame is evaluated <br />here. This represents the time when all of the final PMT watershed has been returned to <br />final grade and is reporting to the drainage system, and all previous in —pit interception of <br />runoff has ceased. Some of the uppermost sub - watersheds are still in a high runoff <br />condition (e.g. CN =85). This represents a worst case assumption for the permanent ditch <br />system, as those upper areas will revert to CN =74 once the revegetation reaches its third <br />year of growth. <br />Exh. 7 -14R -3 Revision Date: 3/27/13 <br />Revision No. TR -97 <br />