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then pumped to an adjacent 5.5-acre settling basin located on a river terrace 20-feet above the river's bank. Another set of pumps would deliver water from the settling basin to the Parachute plant site though an existing buried pipeline. The river intake consists of two 48-inch diameter pipes emerging vertically from the river bed to a concrete crib (44' long x 16' wide) in the center of the river channel. The long axis of the crib pazallels the river's flow. Triangulaz flow deflectors form the upstream and dowt>stream ends of the crib with trash racks (steel screens with 6-inch horizontal by 2-inch vertical openings) enclosing the open sides. Pumps and electrical hazdwaze would be reinstalled on the original concrete pad on a terrace about 20' above the riverbank No major modifications to the systems aze planned beyond reinstalling the pumping and electrical equipment. Biological Assessment --Colorado River Fishes (Colorado pikeminnow, razorback sucker, humpback chub, bonytail chub) This Biological Assessment section for the Colorado River fishes and designated critical habitat and its fmding of affect is intended to supersede that provided in the original Biological Assessment, however, the Consumptive Water Use table provided in the original letter remains accurate. Denletion Effects As mentioned in the opening of this letter, it has been determined that this project is "new" with respect to its depletion influence on listed Colorado rivet fishes. Although American Soda has purchased as portion of a Unocal water right that had been consulted on in 1985 and is a depletion that remains in the Colorado River depletion baseline, that consultation was performed prior to the listing of the razorback sucker and critical habitat designation on the Colorado River below Rifle in 1994. The USFWS has determined that any Federal action that results in a water depletion necessitates a °may affect" determination. Average annual water depletions over the life of the project are estimated to be 1158 acre-feet (revised from the original 1204 acre-feet, see following). This volume represents bout 0.04% of the average daily flow in the Colorado River neaz DeBeque, with the effects becoming more pronounced during typical low flow periods (e.g., Jan-Feb) or during drought years (e.g., 1997) when depletions could account for 0.1 to 0.2% of daily discharge throughout the yeaz. Although consumptive water use is minor relative to the whole, these depletions contribute cumulatively to reductions in the availability, extent, and utility of critical habitat (e.g., reduced peak flows and backwater flooding, decreased water depth in channel features), particularly those associated with reproduction and rearing of young forms. To clarify how BLM calculated the depletion figures used in the original Biological Assessment, any and all water used for this project was taken into consideration for the calculated 1.66 cfs/1204 acre-foot figure as summarized in the Consumptive Water Use table