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Enclosed is some of the vvat aliry• data taken from Trimble Lane an ers Bridge. T.ie shaded numbers show dissolved and oral zinc concentrations on days when conc~ftrations were hi;rher at Trimble Lane than at Bakers Bridge. Zinc is the main metal of concern because the dissolved concentrations are frequently at levels tonic to sensitive aquatic life. (Hardness tends to be low in this stretch ~>f river.) While not conclusive, this data demonstrates the need for more investigation. River Channel Effects. Enclosed are aerial photographs from October 1994 of the three largest operations on the river, Ivtountain Redi Nfix, Burnett's Bar-D pit, and Sandco. The destruction of the river channel is obvious. Mining operations have confined and braided the river channel. The floodway ha:. been narrowed so that floodwaters are less likely to spread out and dissipate their energy. (The floodway waz re- designated by a study a couple of years ago.) This may increase the likelihood of erosion artd flood damage downstream In addition, the shifting of the river bed and the driving of heavy equipment has destroyed riparian areas. Some of these zones may provide habitat for an endangered species, the Southwestern vvillo~•v flycatcher. We suspect that mining has lowered the river bottom as much as eleven feet under the Trimble Lane Bridge. Correspondingly, the water table near the river has fallen. Nearly agricultural area:> and river banks are no longer sub-irrigated. Riparian vegetation such az willows can no longer grow ;utd stabilize river banles because the tops of the vertical banks are too high above low flow water levels. Their roots do not receive enough water. The falling water table may have also dried up riparian wetlands. Along with environmental impacts, the mining operations have affected other property o~vrers. Water-right holders on the Wallace Ditch can no longer divert water because of shifts in the river bed. in stimmary~, vice do not understand the ramifications of gravel mining on such a large scale ur the Animas River. It is irresponsible to continue to issue permits without analyzing and quantifying the .impacts of these operations. The Corps should ar a minimum hold public hearings and conduct an environmental assessment before re-issuing these peanits.