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this approach in his modeling and actually test some scenarios. For example, put in piles in certain locations, of certain depth (how deep, 3m, Sm, 15m?), and try to install lines to distribute subsurface water and see what it looks like. Even putting in subsurface lines is extremely damaging. How will they trench these lines to install them, how far apart are the lines, how to get water to the lines, at what depth should lines be placed. I'm not convinced that this approach has any merit what so ever. We've done lazge scale experiments on the Green River in Browns Pazk to try to build up a water table under cottonwoods, and could not do it, even with very lazge pumps. The statement, "Many site-specific questions still remain to determine the actual impacts associated with the gravel mining operation, which will be answered if mining is allowed. " suggests that the county should permit the gravel pit as an experiment to see what actually happens. That is not realistic. The public should have the best science at their disposal to identify the issues before deciding yes or no on a project. Much more realistic assessments of impacts should be identified. Another issue is the adjacent wetlands, as stated, "Of greater concern are the adjacent wetlands to the proposed gravel mining operation". Water table drawdown more than 0.5 to 0.75 m during the summer will result in wetland plant death, and the loss of the wetlands. The author throws out "A 100 ft buffer from the cottonwood drip line would ensure the health of the cottonwoods given the above mitigation techniques" ,but [can see no analysis in his report that leads to this conclusion. His drawdown figures indicate that drawdowns of more than 1 m, sufficient to injure or kill cottonwoods, will occur along his transect A at 60-65 m from the pit, and along transect B at 90-95 m from the pit. These aze 2-3+ times more than 100'. If the modeling is redone to address the likelihood that the seep face in the pit will be at the pit bottom, not at 4-7 m above the bottom, then drawdowns could extend much further. I have recently reviewed another modeling effort on a pit along the South Platte River, and they show water table drawdowns of 1 m 2,000 feet from the pit. So I suggest that these modeling efforts need critical review by an expert, such as Bill Sanford at CSU, and considerable thought. On page 20 the following paragraph appeazs "Planting cuttings or seedlings in open areas 6- 1ofeet apart may reduce the concern of lateral accretion of the Yampa River towards the gravel pit by stabilizing the stream banks. Although this requires several growing seasons for the seedlings to establish extensive root systems, this will enhance the health of the ecosystem ahd provide for long-term development of the cottonwood canopy and create riparian habitat. A 100-toot buffer from all riparian species is necessary to properly mitigate the cottonwoods and wetland vegetation to establish and sustain along-term healthy riparian corridor." All of this infonnation is incorrect. Cottonwoods cannot stop lateral stream movement. You cannot establish seedlings or cuttings well above the water table, etc. The recommendations at the bottom of page 21 and on page 22, I agree with.