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The general requirements of Rule 4.05.9 are relevant to all impoundments and <br />include: <br />a. Design construction and maintenance and adherence to water quality <br />standards <br />b. Spillway mitigation of piping <br />c. Embankment specifications and freeboard <br />d. Vegetated and stable spillways <br />e. Spillway grades <br />f. Design event (10 y 24 hr) <br />g. Watershed dam design <br />h. Maintenance (11) <br />i. Inspection by PE <br />j. Impoundment reports annual and quarterly <br />Review of the permit with respect to Rule 4.05.9 included: <br />a) Adhering to water quality standards <br />Appendix W includes water quality data from 1988 forward. Surface water <br />monitoring is addressed in permit section 4.8.5 and 5.85.1 Pgs 4-239 to 241a in <br />volume IV. Section 4.8.1 of the permit discusses surface water impacts and <br />mitigation, adequately addressing the requirements Rule 4.05.9 (1). <br />b) Mitigation of piping <br />♦ Question: Please point to the location in the permit describing how piping will be minimized. If <br />this language is not currently present in the permit please add a description of how piping along <br />conduits extending through an embankment is prevented. <br />a. Embankment specifications and freeboard <br />b. Spillway grades <br />c. Design event (10 y 24 hr) <br />Embankment and freeboard design specifications, spillway grades and design <br />event were available for 21 of Trappers 37 ponds in Appendix Q Vol. VII -B <br />section XVI and in permit section XIX. Spillway embankment specifications are <br />found in Table 4.8.7. <br />♦ Question: Please provide spillway embankment designs for all active ponds. <br />Spillway configurations for spillways with a standpipe design are shown in Figure <br />4.8-3 with DQ rates in Appendix Q, section XIV . <br />Open channel spillway locations are shown in Fig 4.8-5, with general design details <br />in pages 4-195 through 4-196b and Figures 4.8-6 a -c and in Appendix Q Section <br />XIX, with designs shown on page 4-196C <br />Trapper Mid Term Review Prepared by: R. Reilley Page 8 <br />Date: June 2015 Document Location: M\\Coal\rar\MidTermReviews <br />