2014-10-21_REVISION - M1988044 (5)

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TR-07 RECLAMATION PLAN Erosion impacts: With a lot of luck, there will not be any undesirable erosion. Perhaps a little sheet erosion, maybe a few small rills here and there, but no gullies or miniature Grand Canyons. The key to effective erosion control is to implement as much control as possible at the start so erosion will not be a problem. Such actions as never having tracks or ridges that run up and down a hillside. Small tracks or ridges at a fairly frequent interval that follow the contour of the hillside are the only patterns that should be present when grading is completed. Having variable topography in drainageways as well as drainages that weave rather than follow straight lines can help prevent gullies from forming. In effect, any topography that can be created that slows the flow of water down a slope will help control erosion. Severe erosion is not caused by high volumes of water; it is caused by high velocity water. Lakes have a high volume of water but don't erode because there is no velocity. The worst micro-topography that can be created is a smooth surface on a slope. Also, excessively compacted soils that prevent water infiltration and encourage water runoff will almost inevitably allow severe erosion to develop. By thinking in terms of keeping water on the site, providing a means for it to sink into the soil, and not allowing the water to flow very far without meeting some kind of barrier or detour to slow it down, most erosion can be controlled very well. Nevertheless and in spite of all best intentions, events such as huge, severe thunderstorms that drop large amounts of water in a very short period of time will eventually occur, even in the driest desert. Even small volumes of water produce high velocity water flow if the water is flowing on a smooth slope and that causes the erosion. If this happens before the vegetation can control the velocity, erosion will occur and sometimes it will occur even with dense vegetation. The best approach when such events happen or when gullies are first noticed forming on the surface is to act quickly to correct the situation. Once this kind of damage begins it can take decades for the natural system to correct the problem and often the gully will grow to many times its original size before it even begins to stabilize. When a gully is found forming in a reclaimed area, take whatever action is needed to immediately correct the problem, or as soon as the soil dries out enough to move equipment into the problem area, if needed, without creating more problems elsewhere by driving over and compacting wet soils. Replacing the lost material and soils may be needed, along with regrading and replanting. In accessing the problem area select a route that will cause the least amount of damage to the other reclamation. For example, if a gully forms that exits the reclamation area at a low spot, try to fix the gully by working directly up the gully path rather than coming in from the side across revegetated land. Most important, attempt to determine what caused the gully to form at that location. Keep in mind that the gully formed at that location for a reason and usually the reason is some weakness in the implementation of the reclamation that allowed the gully to form. Normally, even the largest thunderstorms do not wash everything off the hillsides and instantly create a badland that covers a million acres. That doesn't happen because the system can handle that kind of a precipitation event. Gullies rarely form just because it rained a lot; there is more to it than that. Coal Creek Sand Resource Amendment 3 (2005)- M-1988-044 Exhibit E Page 20