P-402 Upgrade Power Plant & Electrical Distribution System, Makaha Ridge, PMRF, Kauai, Hawaii
P-402 Upgrade Power Plant & Electrical Distribution System is a Design-Bid-Build project awarded in December 2018. The project consists of upgrades to the existing standby power plant Building #711 to provide sufficient generation capacity to support the Pacific Missile Range Facility systems at Makaha Ridge. The power plant building is a low-rise, slab-on-grade, steel-framed structure. Building foundation work includes upgrades to the steel framing, concrete footings, grade beams under the generator room and separate concrete pads to support the engine-generators. Pre-finished metal panels will replace existing asbestos containing wall siding and roof panels. The upgraded power plant will include a generator room with secured open storage, control room, restroom, coffee mess, telecommunications room, and electrical switchgear room. To support the upgraded power plant facility, two new bulk fuel oil tanks, used and new lube oil systems, urea system, HVAC, septic system and a 7.5 ton overhead bridge crane will be installed on the site.
In addition to upgrading the power plant, the project installs a new underground, dual-feed, loop configured, primary electrical distribution system. The primary electrical distribution system runs underground from the utility-owned riser pole just outside the main gate and then along Makaha Ridge Road to the main switching station located in the power plant. Construction of the system includes installation of approximately 60,000 LF of duct bank and 25 octagonal manholes. Additional distribution work includes secondary building service connections to the Makaha Ridge facilities from 29 system service transformers and 10 pad-mounted switches.