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mine bench. Maybe some good could be done in this location with a labor <br />crew and synthetic erosion control materials, but I would like to get some <br />input from an experienced hand (such as Renner) and an <br />engineer/hydrologist (such as Boulay) in this regard. <br />4. There are also problems in a couple segments along the incredibly <br />steep riprapped permanent channel that dives off the No. 1 bench and <br />conveys runoff down the outslope. The first location of concern is <br />approximately midway down the slope, where flow has dislodged some <br />large riprap along a 15 foot segment, with a vertical headcut several feet <br />deep. Access to this location would be difficult and dangerous, and I would <br />be concerned that any fix that could be made would be likely to be no more <br />permanent than the original installation. My inclination here is to just leave <br />this one alone, but I would like to get a second opinion. Next problem is at <br />the toe of the riprapped permanent channel, addressed in Item 1. <br />5. There is a subsidiary gully along the lower end of the bench outslope, <br />which eventually feeds into the main channel below the toe of the riprap. <br />This gully is intermittent, approximately 150 feet in length, and <br />approximately 18 inches deep in various segments. If the main channel <br />riprap toe gully is repaired, it may be advisable to repair this subsidiary gully <br />as well, although it is a lower priority item. <br />I think these are the main items of concern at the site. <br />Photo Summary <br />A photo summary of the features described above can be accessed on the M <br />drive, "coal /dtm/pictures /Fruita ". <br />3361 is the sediment pond from a distance. <br />3373 is the excavation at the base of the riser, showing the defective gap <br />behind the gate device. <br />3374 is the open channel emergency spillway inlet. <br />3365 is distant view of the #1 Mine Bench outslope. <br />3380 is rill erosion on lower reclaimed road bed; 3382 are ephemeral <br />drainage chutes that contribute to this problem. <br />3384 is an area of poor vegetation establishment on the Mine 2 backfill <br />(above the lower SS outcrop). Roughening and seeding of this small slope <br />may be warranted if budget allows, but is not a high priority. <br />