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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. gradient is met. The extent of disturbed azea slope draining into the diversion appears to exceed the %z acre projected and modeled in the permit. Operator will need to implement additional sediment control measures along the length of the ditch if permit specified soil roughening and mulching are not fully effective in preventing excessive contribution of sediment into the ditch. The upper segments of the CRDA-2 East Collection Ditch, that drain the benches currently being reclaimed, will need to be graded to fmal design configuration andriprapped in accordance with permit specifications in association with CRDA-2 fmal grading andtopsoiling. Coal Creek Permanent Diversion The Coal Creek permanent diversion appears to have been essentially completed, largely in compliance with approved design. At one location near the lower end of the segment just above the 72" culverts, additional grading appeazed to be warranted to better define the channel and ensure compliance with design depth specification. In one other location further upstream, the channel is somewhat constricted by sandstone outcrop, and may not meet channel width specification. However, in this location, channel depth significantly exceeds specification, and channel capacity would appeaz to be adequate without modification. Any such deviation from design spec will need to be addressed in theP.E. construction certification, and the implications with respect to channel capacity and functioning assessed. At the upper end of the channel segment immediately below the concrete dip section, the south bank of the channel had been protected with a 300 foot section of large riprap. Due to the low frequency of significant flows in the channel, the remaining channel banks should be seeded with thegreasewood components permanent seedmix. Most of the channel slopes will require additional roughening bydozer tracking or other methods to prepaze a suitable seedbed. Topsoil piles 7, 8, and 9, adjacent to the channel segment on either end of Pond 10 had been used up during the CRDA-2 reclamation project. These disturbance areas and additional miscellaneous disturbances along the lower flat areas adjacent to the channel will need to be ripped, seeded and mulched, also with the greasewood components mix. Upon completion of all dirt-work, operator will need to ensure that required small azea exemptionberms are intact, for those portions of the stockpile disturbance that do not drain into Pond 10. CRDA-1 There was no activity at CRDA-1 at the time of inspection. Grading on the pile has resulted in a slightly crowned top of pile, per approved design. Reconstructed Terrace Drain #4 has been roughly established, and the over-steepened crest noted in previous inspection reports had been eliminated, with the exception of a short segment of the terrace drain at the northwest end. Additional work will be required to establish final terrace grade, and to achieve design grade on the refuse slope above the terrace, in some locations. A section of the inside ditch along the "in pit" road above the forks of Haul Road 5 and the XCEL ash road had been partly obscured by construction traffic crossing over onto [he terrace bench. The ditch needs to be re-defined, and a temporary culvert segment installed. Upon completion of the project, the ditch segment and water bars along the "in pit" road segment will need to be reestablished.