We began this replacement project by removing and disposing of the existing two 126-inch diameter penstock butterfly valves and associated equipment and then designing, fabricating, installing, and testing the new equipment of like size. We also replaced the adjacent penstock sections, valve actuators, a hydraulic power unit, appurtenances such as pressure equalization valve and piping, the grease lubrication system, and power and control wiring. New installations included an emergency closure system, pneumatic locking pin system, bypass piping and valve, access platforms, and other appurtenances.