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2 This project will result in the creation of 4 ponds linked to the 100-year floodplain of the Colorado River. Threatened and Endangered fish species occur in the Colorado River adjacent to this parcel. The CROW is concerned about the proliferation of non-native fishes in ponds near the river, and the potential for those fish to enter the Colorado River system to the detriment of native fish. This project proposes to capture the irrigation return water associated with a portion of the Grand Valley Canal system in Lake 4, and discharge it from Lake 1 directly into the North channel of the Colorado River. Experience has shown that even without stocking, non-native fishes will enter and proliferate in ponds fed by irrigation wastewater. Because of this, we recommend screening of both the inlet to Lake 4 and the outlet to Lake 1 to prevent the movement of non-native fish into the river. The U.S. Fish & Wildlife Service and the CROW can provide guidance and construction specifications for non-native fish barriers for this project. The mining plan indicates that the mature cottonwood groves on the east and west boundaries will not be impacted. De-watering of the pits during excavation may lower the water table to the point where these trees experience drought stress, however. Artificial watering of existing trees should be implemented if that occurs. No mention was made of the line of younger cottonwoods found in Mining Area #2. All cottonwoods occurring on this site are considered important to wildlife. If those trees cannot be avoided, we recommend replacement at the ratio of 10 saplings/pole-sized trees for each _ __, _ cottohwood-removed- All"trees planfed "should be protected from browsing damage `with wire cages and artificially watered until the water table is reached. The post-mining uses proposed for the property include Commercial/Industrial in the northern portion and Wildlife Habitat in the southern portion of the property. The Wildlife Assessment (Exhibit H) states that "with the p/andngs of addibona/ bees and shrubs addidona/strata and vegetation layers wi/l be added to the site, creating improved cover, foraging, roosdhg, and nesting alas for wi/dlife" It further states that 'with the conb~/and/or removal of noxious species...and rep/acement of desirab/e g2ss, forb, shrub, and bee species, mining and reclamation wi// res~/tin enhancement of wi/dlife habitat on site° I agree, but note that the vision put forth in the Wildlife Assessment did not carry over to the Reclamation Plan. No trees, shrubs or forbs were even included in the revegetation mix for the property. The revegetation mix for upland areas includes only 2 grasses, both of which provide cover but are limited in value as wildlife forage. The proponent states that 'ho strict vegetation success criteria is warranted"for the site but puts forward a figure of 30% live perennial cover for the uplands, and 50% for the wetland areas. The existing groundcover was estimated to be 10% to 20% depending on the exact location, suggesting that much of the area may not even equal, let alone exceed the pre-mine conditions. That suggests the need to apply revegetation success criteria to the Reclamation Plan. Because of the USACOE's need for more detailed information on the distribution and classification of wetlands on the property, I am not able to determine if the Reclamation Plan will adequately mitigate for the impacts to the existing wetlands. In general, it is much more difficult and expensive to re-create a functional wetland than it is to just avoid it. The proponent may wish to reconsider connecting the lakes with culverts, and instead evaluate if meandering stream-like open swales would accomplish the same purpose in an environmental-friendly manner. While the revegetation mix proposed for the lakeshore area appears good, it would be improved by the addition of willows and cottonwoods. Contouring portions of the lakes to the ratio of 6H/1V, as United Companies proposed for their 19 Road Pit, would increase the value of the lakes as wildlife habitat. It is unknown if the creation of wet lands (i.e. lake shallows) adequately mitigates for the loss of functional wetlands from the USACOE's perspective. The Reclamation Plan would benefit greatly from the incorporation of trees, shrubs, forbs, and additional grasses into the revegetation mix. Cottonwoods and willows are recommended tree species. Skunkbush sumac, shadscale saltbush, and 4-wing saltbush would be desirable shrubs. Cicer milkvetch is a recommended forb. The addition of Indian ricegrass, needle-and-thread grass, and western