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Roadside .."Aemorandum September 21, ?000 Page 2 vehicles pulling horse trailers. During our meeting we visited the site to discuss detail options. It became apparent that we did not disagree regarding any hydrology or fluvial geomorphology issues. The BLM prefers that the culvert crossings should be retained for access reasons, so our discussion focussed on ground manipulation options that would facilitate this goal, while also meeting regulatory, erosional and hydrologic equilibrium requirements for the channel area. In addition to the morning meeting with BLM, I also traveled to the site during the afternoon to observe flow conditions in the area during an ongoing precipitation event. This trip occurred at about 4:00 p.m., and I made the following observations: oThe Coal Creek Channel was conveying runoff at a depth of about 6 to 12 inches at the multiple culvert concrete crossing location. This flow was occurring over the entire incised channel width. QA1l of the culverts at the concrete crossing were passing flow, but a large percentage of the runoff was passing through the two southern (right hand/downstream) culverts, with lesser amounts of runoff passing through the other culverts. This resulted in a significant concentration of flow against the channel bank located on the southeast side of the channel, downstream from the crossing. This concentration of flow was causing bank slough and scour. QConcentrated surface runoff was also observed in the south road ditch and along the road surface originating upstream from the crossing, at the area above the upstream south tributary and culvert, specifically at the location where the road topography breaks over a minor divide to the upstream low water crossing. This runoff was captured by the road ditch, and passed intact to the multi-culvert crossing, then across the concrete structure to a hole in the embankment at the northeast corner of the crossing structure. This surface runoff appears to be a main contributor to the erosion observed at the northeast structure edge. QAII of the RDA perimeter ditches were conveying significant flow volumes, and the southeast perimeter ditch of the south RDA was near capacity and close to conveying flow onto the adjacent road. The flows were entering both sediment ponds at a significant rate, but neither pond had discharged by the time I left the site. All RDA runoff was dark black in color, pointing to the ongoing need for drainage and sediment control at the RDA facilities. Reclamation of these facilities should receive high priority attention as we discuss any revised reclamation plans and schedules. The following details were discussed with Messrs. Fowler and Scheidt, and we need to work with the coal operator to revise the reclamation plan accordingly. The final reclamation plan will include the retention of all three road culvert structures in the area of the RDA facilities. This will meet the BLM land management and public access concerns. The upper-most and lower-most culvert crossing have sufficient flow capacity to