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' site. An inactive gravel-pit quarry is located to the west of this site and would be the best means to access the site. Little or no vegetation exists in this old oxbow. Productive topsoil would be stockpiled and later used to grade the site to the river. Most likely, at Site 1 the predominant material will be cobble sized; at Site 2 sandy-loam. The CDOW may have use for either of these excavated materials in various operations at the Escalante SWA or at other state wildlife management areas. If this conceptual plan is approved, the impacts of the proposed action will be determined following the process required by the NEPA. All necessary documentation would be prepared to obtain the required state and federal permits for the proposed development. 1 PROPOSED OPERATION OF BOTTOMLANDS Criteria for Operation At Site 1 the inlet/outlet structures will require periodic cleaning during ' the spring high flows. Because the primary intent of this site is to conduct biological studies, water control structures will provide the flexibility to regulate the volume and velocity of flow through the unit during high water. For example, if the velocity becomes too high, the inlet structure could be closed and water be allowed to "back into" the site at the outlet structure. Within the site, stop-logs will be used to regulate flows and water levels for the three compartments. Fish screens could be installed at each stop-log water control structure located within the site. This would allow researchers to further compartmentalize the unit to conduct separate biological studies. ' Removable fish screens at the inlet and outlet structures will allow researchers to regulate fish species from entering or leaving the site. Although not planned at this time, a fish trap could be installed to monitor the number and species of fish that attempt to enter or leave the site. However, the disadvantages of fish traps are, 1) they are labor intensive and require routine checking, 2) fish may be "trap shy", and 3) they can be plugged by debris and/or beaver activity. Other than spring runoff in which river water would be diverted through the site, water levels in Site 1 would be self-regulating by surface and ground water from irrigation returns and the river. The 6-foot deep channel will not dry up because groundwater will maintain water levels even during extreme low flows in the river. The proposed location of the inlet is on the north side of the river which is presently the outside and erosional bend of the river. The location of the proposed outlet structure is more protected from the main channel. Although the ' extent and amount of annual sediment buildup at the inlet and outlet are unknown, it is believed that minimal sediment buildup will occur at these two locations. At Site 2, there will be no water control structures. From the design criteria, this site should remain wet for about 6-8 weeks in May and June during high flows. Annual maintenance may be required to remove and lower the berm ' 19