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1. Trapper did not submit detailed designs for post- mining drainage channels, as required by Rules <br />2.05.3(4), 4.05.3(1), 4.05.3(1)(e), 4.05.3(7). <br />a. Rule 2.05.3(4)(a) — A general plan and detailed design plan shall be submitted for each sediment <br />pond, impoundment, other treatment facility and diversion proposed to be constructed within <br />the permit area. Please provide detailed design plans for each postmining drainage channel. <br />b. Rule 4.05.3(1)(e) — channels must be designed, located, constructed, maintained, and used to <br />minimize adverse impacts to the hydrologic balance, and to be stable. Trapper has offered <br />details on how the channels might be constructed and maintained, but has not provided specific <br />design information. Please provide design information for each postmining drainage channel <br />to include the minimum channel dimensions and details of any required velocity reduction <br />measures. The dimensions and channel properties must be based on the anticipated runoff <br />for each specific watershed, based on watershed size, topography and cover; the design <br />precipitation event; runoff potential, etc. <br />c. Rule 4.05.3(7): <br />(i) — channel linings, including channel riprap, shall be designed using standard engineering <br />practices to pass safely the design velocities. Please provide design information for each <br />postmining drainage channel to include the minimum channel dimensions and details of <br />required velocity reduction. The dimensions and channel properties must be based on the <br />anticipated runoff for each specific watershed, based on watershed size, topography and <br />cover; the design precipitation event; runoff potential, etc. <br />(ii) — Freeboard shall be no less than 0.3 feet. Please provide details on the proposed <br />channel dimensions so that the Division can determine whether the designed channels <br />maintain the required freeboard. <br />Trapper must submit the information required in Items (a) through (c) for all postmining drainage <br />channels to be constructed, completed, or reconstructed during the current permit term. <br />2. Trapper did not submit designs for the three proposed sediment ponds that are shown east of the <br />current disturbance boundary, as required by Rules 2.05.3(4) 4.05.5, 4.05.6, and 4.05.9. Prior to any <br />surface disturbance east of the Deal, Middle, East Flume, and East Middle Flume watersheds, <br />Trapper must obtain approval for and construct appropriate sediment control for all areas proposed <br />to be disturbed. Please provide the required design information for sediment control measures to <br />be used for proposed disturbance east of Deal, Middle, East Flume, and East Middle Flume <br />watersheds. <br />