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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. General Comments This was a partial inspection of the mine site, conducted by Dan Mathews of the DMG Grand Junction Field Office. The inspection was conducted August 8, 2006. Tonya Hammond, SCC owner representative, was present during portions of the inspection. Weather was partly cloudy and warm. Ground conditions were variable (moist to dry) across the site, depending on location. Effects of Auoust 1 Storm on Coal Creek The primary purpose of this inspection was to assess effects of a storm event of August 1, 2006 that caused over-bank flows on Coal Creek through the permit area. There was a high intensity storm event that passed over the eastern part of Grand Junction on the late afternoon of August 1, causing localized flooding along Interstate 70 in the Clifton vicinity. Apparently, this storm system also passed over the upper watershed of Coal Canyon in the Bookcliffs northwest of Cameo. Tonya Hammond of SCC notified me on August 2 that she had "traveled out to the mine site late on the afternoon of August 1, after observing that the intense storm system may have tracked over the mine area. Tonya reported that rain gauges at the South and North Portal Areas had recorded only 1/3 inch and'/< inch, respectively, but she surmised that higher rainfall amounts likely fell higher in the Coal Creek watershed, because by the time she arrived on site at approximately 4:30 pm, Coal Creek was flooding out of its banks. She emailed two video clips that she recorded. The first clip was at the Haul Road 4 crossing of Coal Creek, between the North Portal Area and the CRDA Refuse Areas. At this location, troth large culverts (81 "x59") were flowing at capacity, and water had backed up in front of the road fill and was washing across the road. A second video clip was taken at the lower-most dip section crossing of Coal Creek, on the UTL haul road a short distance upstream from Coal Creek's confluence with the Colorado River; the creek was flowing at an extremely high level over the top of the concrete dip section structure, with water extending a considerable distance up the road on both sides of the concrete crossing. I began the inspection on Coal Creek upstream from the mine disturbed areas, at the location where the Coal Canyon Road crosses Coal Creek (graveled dip type crossing), just downstream from the Greasewood Reference Area. From high water marks it was apparent that the creek had flowed out of its channel, well up on the flood plain along this segment (Photos 2705 through 2709). Further downstream, at the meander just up the road to the northwest of soil borrow area CBA-2, the stream flowing out of its banks had overtopped the low rise between the Coal Creek channel and CBA-2. As a result, a portion of the stream flow was diverted away from the channel and had flowed southeast across a corner of the borrow area, past a small riprap stockpile, into Sediment Pond 11. Water was pooled several feet deep in Pond 11, but the embankment appeared to be sound and the pond had not over-topped. Water level was approximately 4 feet below the low point of the embankment at the time of the inspection. Photos 2710 through 2715 are of the CBA-2/Pond 11 vicinity. The pond will need to be dewatered as necessary to provide storage for the 25 year, 24-hour event, when sufficient settling has occurred to allow for discharge in compliance with CDPS permit requirements. Subsequent sediment excavation may be warranted, depending on quantity of material deposited. Good establishment of recently seeded shrubs and fortis (salt bush and Palmer penstemon) was noted on portions of the embankment that were not disturbed by recent culvert maintenance work. Coal Gulch, the Coal Creek tributary that runs along the southeast side of CBA-2, appears to have flowed at modest levels as a result of the storm. It was noted that minor channel scour in Coal Gulch (due to the most recent or previous flow events) has exposed a segment of culvert that was previously buried beneath the channel. The culvert is still partially buried, and is in the location where a temporary reclamation road previously crossed the channel to provide access from the CBA-2 up onto CRDA-2 Refuse Disposal Area. The old buried culvert needs to be removed from the channel and properly disposed of. 3