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was initially filled in 1963. A concrete cutoff wall was placed at the left abutment, and aconcrete-lined tunnel with approximately 46 drainage holes drilled into the rock foundation was constructed at the right abutment. Areas of renewed seepage appeared on the right abutment in November 1995. This initiated a detailed study of the seepage conditions and a consultant review of the situation, As a result of these studies, the frequency of seepage monitoring was increased. It was also determined that additional foundation instruments were required in the abutment to define the relationship of the water level in the abutment with rising and declining reservoir levels. The installation of these instruments began in the fall of 1997 and was completed in the spring of 1998. In November 1997, a comprehensive facility review was performed at Navajo Dam as part of Reclamation's Dam Safety Program. The comprehensive facility review consisted of an independent facility inspection as well as a state-of- the-art technical evaluation of the dam's design, construction, and performance. The report was completed in 1998 and included an evaluation of present seepage conditions as well as recommendations for future monitoring of the structure. A risk/analysis process and requested performance parameters were initiated in 1998 and are expected to be completed in early 1999. 4. Wayne N. Aspinall Storage Unit The Aspinall Unit includes three major dams and powerplants in the canyon of the Gunnison River downstream from Gunnison, Colorado, and upstream from the Black Canyon of the Gunnison National Monument. The three dams are Blue Mesa, Morrow Point, and Crystal. Uprating of Morrow Point Dam generator units was completed in 1993. The plant nameplate capacity was increased from 120 megawatts to 156 megawatts. The National Park Service administers the recreational facilities. In 1996 there were 1,017,256'"~ visitors (latest figure available). Similar to Glen Canyon, Flaming Gorge, and Navajo, the Aspinall Unit is being evaluated to determine how operations can be modified to conserve native and endangered fish populations. Section 7 consultation with the Fish and Wildlife Service on the operation of the Aspinall Unit continued in 1998. As part of this consultation, afive-year effort to study the effect of various release patterns on habitat, reproductive success, and reintroduction of endangered fish in the Gunnison River is underway. The goal is to provide a more natural hydrograph. Additionally, the Aspinall Unit was operated in water year 1998 as if the draft contract among Reclamation, the National Park Service and the state of Colorado to deliver water from the Aspinall Unit to the Black Canyon of the Gunnison National Monument were in place. The operation was also coordinated with the Fish and Wildlife Service and others interested in the operation of the Aspinall Unit. A draft biological opinion on the operation of the Aspinall Unit as it affects endangered fish will be prepared in 1999. An interim contract has been executed to provide flows to study and protect endangered fish species in the lower 38