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22 517 GEOGRAPillC SCOPE OF THE AMP 518 AND GCMRC MONITORING AND RESEARCH PROGRAMS 519 The scope of the AMP is described as the Colorado River ecosystem within Glen 520 Canyon National Recreation Area and Grand Canyon National Park (Figure 2.2). The 521 Colorado River ecosystem is defined as the Colorado River mainstem corridor and 522 interacting resources in associated riparian and terrace zones, located primarily from the 523 forebay of Glen Canyon Dam to the western boundary of Grand Canyon National Park, a 524 distance of approximately 300 river miles. The scope of AMP and GCMRC activitie~o'<r 525 includ~ limited investigations into some tributaries (e.g., the Little Colorado and Paria 526 Rivers). The effects of Glen Canyon Dam operations on the Colorado River ecosystem 527 below Separation Rapids, such as those seen during the 1996 BHBF test, might result in an 528 extension of the geographical scope of the long-term monitoring program. The long-term 529 monitoring program will also include, pending review by the TWG, the monitoring of 530 selected water quality attributes in Lake Powell,that may be affected by dam operations and 531 have the potential to affect downstream resources. 532 The lateral extent of the monitoring effort is defined by the extent of processes and 533 conditions influenced by dam discharges and river flows associated with operating criteria in 534 the ROD. The relevant lateral study zone area is the maximum regulated discharge and the 535 inundated area for annual pre-dam peak flows. Arroyo head cutting caused by current low .(1..- 536 flow operations may extend above this level. Thus, i~prudent in some areas of the '. ~ 537 Colorado River ecosystem to include elevations above the stage associated with flows of ' 538 100,000 cfs. 539 The AMP is constrained by design. For this reason upstream monitoring by GCMRC 540 in Lake Powell, and downstream in tributaries, (i.e. Little Colorado River), is constrained to 541 those probable effects on downstream resources associated with dam operations. AMP 542 participants realize these to be constraints that inhibit understanding of the entire system and 543 therefore accept that scientific information from programs outside the AMP may be needed 544 as a means of strengthening understanding of the entire Colorado River ecosystem. In this 545 regard, scientific review by GCMRC and the application of GCMRC protocols to programs November S, 1998 SecoDd Draft - Do Not Cite, Pbotocopy, or Distribute