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engineering and design, construction supervision and administration, engineering during construction, site geologic explorations, topographic surveys, and miscellaneous costs. The total job cost for Alternate No. 1 is $839,200. b. This design, as studied and estimated, includes the trash shear boom constructed from logs (see Plate 14 for details).- The log boom, designated as Option A, is considered an appropriate design choice. Option B, a Slickbar trash boom may also prove to be appropriate for this installation. If so, the selection of Option B would be a sub- stantial cost savings to the project. The final choice of trash boom will be made during preparation of plans and specifications. c. The design life of this project is estimated as 50 years, taking into consideration the age (68 years o1 d) of the existing dam structure. During the life of the project, the large mechanical equipment items should only require proper maintenance. The only item that would require replacement, during the project life, is the log trash shear boom. Based on a study of trash shear booms at a Corps of Engineers dam, the life cycle cost is lowest for a log and timber type boom. The log and timber components have a 10-year life and the boom cable has a 25-year life. All other components have a design life longer than 50 years and would not require replacement. The present worth of the trash shear boom replacement costs for this alternate is $22,700. C. Alternate No. lA. 1. Description of Major Features. a. This alternate also relates to preliminary Alternate F described previously. This alternate was proposed for study during the 60-percent review meeting to examine potential cost savings. See Plates 6 and 7 for plan and profile views. This vertical slot/orifice ladder has three downstream entrances - a west side entrance, an east Slde entrance, and a downstream entrance. The ladder configuration was deter- mined by the number of common walls that could- be utilized and still place the entrances and exit in desirable locations. This change should reduce mechanical piping and therefore reduce costs over Alternate No. 1. Upstream of the last pool, the fishway exits into the forebay at least 40 feet from the spillway crest or sluice gates. The slope of the ladder floor is 1 foot vertical to 20 feet horizontal. The ladder also has pro- visions to adjust the length and number of pools. The pool length is adjusted by placing or removing lightweight weir boards (refer to para- graph 3, Operational Flexibility). • 16