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<br />" <br /> <br />VI. ENVIRONMENTAL COMMITMENTS AND MONITORING <br /> <br />The following environmental and monitoring commitments will be carried out under the preferred <br />alternative or any of the other restricted fluctuating or steady flow alternatives described in the <br />final EIS. A detailed description of these commitments can be found on pages 33 - 43 of that <br />document. All practicable means to avoid or minimize environmental harm from the preferred <br />alternative have been adopted. <br /> <br />1. Adaptive Management: This commitment includes the establishment of an Adaptive <br />Management Workgroup, chartered in accordance with the Federal Advisory Committee Act; and <br />development of a long-tenn monitoring, research, and experimental program which could result <br />in some additional operational changes. However, any operational changes will be carried out in <br />compliance with NEP A. <br /> <br />2. Monitoring and Protection of Cultural Resources: Cultural sites in Glen and Grand <br />Canyons include prehistoric and historic sites and Native American traditional use and sacred <br />sites. Some of these sites may erode in the future under any EIS alternative, including the no <br />action alternative. Reclamation and the National Park Service, in consultation with Native <br />American Tribes, will develop and implement a long-tenn monitoring program for these sites. <br />Any necessary mitigation will be carried out according to a programmatic agreement written in <br />compliance with the National Historic Preservation Act. This agreement is included as <br />Attachment 5 in the final EIS. <br /> <br />3. Flood Frequency Reduction Measures: Under this commitment, the frequency of <br />unanticipated floods in excess of 45,000 cubic feet per second will be reduced to an average of <br />once in 100 years. This will be accomplished initially through the Annual Operating Plan process <br />and eventually by raising the height of the spillway gates at Glen Canyon Dam 4.5 feet. <br /> <br />4. Beach/Habitat-Building Flows: Under certain conditions, steady flows in excess of a given <br />alternative's maximum will be scheduled in the spring for periods ranging from 1 to 2 weeks. <br />Scheduling, duration, and flow magnitude will be recommended by the Adaptive Management <br />Work Group and scheduled through the Annual Operating Plan process. The objectives of these <br />flows are to deposit sediment at high elevations, re-fonn backwater channels, deposit nutrients, <br />restore some of the natural system dynamics along the river corridor, and help the National Park <br />Service manage riparian habitats. <br /> <br />5. New Population of Humpback Chub: In consultation with the U.S. Fish and Wildlife <br />Service (FWS), National Park Service, and Arizona Game and Fish Department (AGFD), <br />Reclamation will make every effort (through funding, facilitating, and technical support) to ensure <br />that a new population of humpback chub is established in the mainstem or one or more of the <br />tributaries within Grand CanY~lD. <br /> <br />6. Further Study of Selective Withdrawal: Reclamation will aggressively pursue and support <br />research on the effects of multilevel intake structures at Glen Canyon Dam and use the results of <br />this research to decide whether or not to pursue construction. FWS, in consultation with AGFD, <br />