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III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken d~iring the inspection <br />and the facts or evidence supporting the enforcement action. <br />Ditch and Channel Measurements section of this report. DMG has not yet taken - <br />measurements of the new upper diversion, but such measurements will be taken either <br />during or prior to the Phase I bond release inspection in May 2003. <br />General configuration of the final graded upper bench slopes and top of pile appeared to be <br />in accordance with the approved design. The top of pile is mildly crowned, with gentle <br />slope toward either the upland diversion or the upper most terrace drain. Bench outslopes <br />are generally in compliance with design gradient and bench heights. DMG slope <br />measurements taken during this inspection are documented in the Refuse Area Slope and <br />Terrace Drain Measurements section of this report. <br />Construction design for CRDA-2 did not include installation of an underdrain. <br />Several maintenance items were noted during the inspection. <br />CRDA-2 Maintenance Items and Requests <br />1) There was shallow puddling on Terrace Drain #3, in the immediate vicinity of the terrace <br />drain crossing of the reclaimed temporary road. Maintenance is necessary to establish <br />postive grade across the reclaimed road. <br />2) The lower 30 foot segment of the west end of Terrace Drain #4 (the upper terrace drain) <br />was constructed at a slightly steeper grade than specified, in order to tie into the upper end <br />of the west perimeter collection ditch. Minor erosion has initiated on this steeper segment <br />of the terrace drain, and there was evidence of minor puddling along a short flat segment <br />immediately up-gradient from the steep segment. Maintenance is necessary to establish <br />positive grade to the perimeter ditch, and to stabilize the steep lower segment of the drain. <br />It the grade of the lower segment cannot be sufficiently reduced, proper installation of <br />adequately sized riprap would appear to be necessary. <br />3) There appears to be an inconsistency with regard to terrace drain width specificatign <br />between text on page 13-21, and map Exhibit 53. Text indicates minimum terrace drain <br />width of 10', while map indicates terrace drain width of 15'. Please address the apparent <br />inconsistency between permit text and Exhibit 53, with regard to RSRDA terrace drain <br />width, and amend the permit as appropriate. Please address the inconsistency and amend <br />the permit prior to the Phase I bond release inspection. <br />CRDA-1 <br />Refuse Area CRDA-1 was fully reclaimed in 2002, with the exception of a temporary road <br />segment along the south side of the pile, from the end of Haul Road 5 (where the Xcel ash <br />disposal road forks off to the left), up to the top of the pile. The temporary road has been <br />left open to allow for disposal of coaly material from future clean-up of remaining disturbed <br />areas at the loadout and along the conveyor corridor. The lower three benches of the pile <br />had been permanently reclaimed in 1994. The upper two benches (including the top of pile) <br />were final graded, cover-soiled, seeded and mulched in April 2002. The final reclamation <br />project in spring 2002 included the final design construction and riprap installation of the <br />8 <br />