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ii. The operator designed five culverts along RP 2/3 and 4 and RP Sa, to pass haul <br />road runoff from the 100 yeaz, 24 hour design storm event. From the maps provided, it <br />appears that certain of the culverted ditch segments are at a lower elevation than the <br />ultimate crest of the refuse azea, and as such would need to route runoff associated with <br />refuse pile areas as well as the haul road. This issue is clouded to some extent because <br />the map shows only one ditch along the eastern side of RP 2/3, rather than the two <br />parallel ditches that occur along the site (the refuse area perimeter collection ditch, and <br />the roadside ditch). The amended map should depict both ditches, and all culverts on <br />both ditches should be shown (with size indicated). Culverts which would convey runoff <br />from the refuse area will need to be sized to take into account runoff from the <br />contributing area of refuse. <br />b) This question has been adequately addressed. <br />c) i. No ditch or culvert designs were submitted for CMP # 1, and these designs will <br />need to be provided. <br />ii. On Map 86, it is erroneously indicated that CMP #4 was plugged, and drainage <br />formerly conveyed to CMP #4 is routed to CMP #3. Map 139 correctly indicates that it is <br />CMP#5 which did not function and that drainage is being bypassed to CMP #4. Drainage <br />area for CMP #5 is apparently 9.27 acres, and drainage area for CMP #4 is apparently .66 <br />acres. Both culverts are 18" diam. CMP. Map 86 needs to be corrected with respect to <br />which culvert was plugged (CMP #5), and which culvert will be replaced with a 21" <br />CMP (apparently CMP #4). CMP #4 should be sized to pass the combined storm flow <br />from the CMP #5 and CMP #4 watersheds, if this is the case. <br />Issues from 1/14/98 Adequacy Letter <br />All issues were adequately addressed. <br />Miscellaneous Issues <br />15. The reclamation cost estimate was updated to take into account recent revisions which <br />approve combination of two refuse sub-areas, survey documentation of subsoil/topsoil <br />volumes, and reduction of the 4 foot cover replacement requirement. These changes <br />resulted in a net decrease in the reclamation liability, of $34,151.00. Cost estimating <br />sheets are enclosed. <br />16. Amended Map 77 includes a notation referencing a "Temporary Refuse Storage Area #3, <br />along a 2300 foot segment of the haul road". This may be a relic, and if so should be <br />deleted. If not, we would require additional information regazding refuse volume, <br />timeframes, sediment and drainage controls, etc. There would appeaz to be significant <br />potential for the refuse to contribute to drainage maintenance problems associated with <br />