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<br />IV. <br /> <br />Study Schedule: <br />Final Swnmary: <br /> <br />1994 through 1998 <br />March 1999 (Remediation Phase) <br /> <br />V. Relationship to RIPRAP: <br />Colorado River Action Plan: Mainstem <br />II.A. To restore and manage flooded bottomland habitat. <br /> <br />VI. Accomplisiunent of FY 97 Tasks and Deliverables, Discussion of Initial Findings and <br />Shortcomings: <br />Water quality parameters continued to be measured in situ at 6 sample locations on a <br />weekly basis. Water and invertebrate samples have been collected on a monthly basis <br />and sediment samples collected on a semi-annual basis for analysis of selenium and <br />other trace elements. Water chemistry analyses have been performed on water samples <br />on a monthly basis. Graphs depicting the data received, to date, from the analytical <br />laboratory are attached. <br /> <br />Depuration rates in adult razorbacks were also documented at 30, 60 and 90 days after <br />the fish were placed in ponds at Horsethief Canyon State Wildlife Area. <br /> <br />An ichthyofaunal survey was conducted by Fish and Wildlife Service personnel within <br />the channel area of Walter Walker SW A that was flooded during high flows. Sampling <br />was done by various methods on a weekly basis from May 7 through July 9. <br /> <br />Results of monitoring while water control structure was open during 1997 to the river <br />were as follows: 64% of 1,987 fishes caught were native and 36% were nonnative. In <br />1995 and 1996 (prior to diverting river water into the backwater), the catch was <br />predominantly nonnative fishes. A total of 55 Colorado Squawfish were captured. All <br />Colorado squawfish had muscle plugs taken for selenium residue analysis. Repeated <br />use of this area by individual Colorado squawfish was documented. <br /> <br />Bed profiles were surveyed at 17 cross sections. Water elevations were documented <br />throughout the season by a recorder and gaging station installed at the lower end of the <br />channel area. <br /> <br />Sediment traps were installed and monitored at strategic points in the channel area. <br /> <br />VII. Recommendations: <br />Recommend remediation phase (channel monitoring) continue in 1998. <br /> <br />VIII. Project Status: <br />On-track and ongoing. <br /> <br />2 <br />