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of deepening and the upstream length, this could result in drying up of some sloughs/ backwaters in the Walter Walker Wildlife Area. F. Reportedly, past experiments with similar inflow structures at Walter Walker Wildlife Area and at an old pit area near 30 Road failed, in ways similar to those described herein. G. Any diversion of flood waters through the pit would reduce flood peaks and would result in above normal deposition of sediment in the downstream "island" area, thus altering the existing channeVslough/backwater system. This process is somewhat similar to what occurred in Grand Canyon below Lake Powell, which led to the planned "flood" releases of a few years ago in an effort to remove accumulated sediment. A critical issue is related to the mere existence of a pit whether reclaimed as a pond or marsh. The present pit site is a nearly flat flood plane where thin alluvial soil is underlain by coarse materials (sand, gravel, cobble, and boulders). This coarse material is much more resistant to erosion during over-bank flooding than is the soft sand and silt that would fill the pit. Thus, the project itself would increase the risk of diverting the main river, regardless of the final state of the pit. Flood overflow into the pit would rapidly erode the steep pit wall and cut headward into the main river channel, thereby diverting the river. I assume the pit operator will take measures to minimize the risk of inflow during operations. However, all involved should be aware of the increased risk of a major channel diversion caused by the pit. 3. Some change toward a "marsh" habitat might be achieved by allowing flood flows to enter the pit only at the downstream end, and thus minimize or prevent the problems noted above. A moderate-height levee along the north edge of the pit, south of the tree area, would allow over- bank high flood waters to spread south of the present channel, but at low velocity along the levee. This would greatly reduce the risk of a full-scale channel diversion. In summary, the potential for the proposed "flow-through" system to cause losses in the known, existing riverine habitat, at the "island" and at Walter Walker Wildlife Area, coupled with the uncertain biological value of the "ne.v" habitat, would seem to justify a re-evaluation of the concept. I appreciate your interest in this matter and for the opportunity to comment. Don't hesitate to call if you have questions. Thank you. Sincerely, Glen A. Miller