About the Project

SSFM provided structural engineering and civil engineering services for the overhead structures required for the planned X-90 breaker at the Harmon Substation, for a new electrical manhole, and a new electrical duct bank located under the existing travel lane of Marianas Boulevard to Andersen Air Force Base.

This project involves a new 34.5 kV (kilovolt) underground electrical transmission line to increase the capacity and reliability of the existing electrical utility infrastructure. This modification supports increased personnel, facilities, and operations associated with the relocation of US Marine Corps ground and aviation unit personnel and activities from Okinawa to the Naval Communications Telecommunication Station at Finegayan, Guam. The new electrical line is routed underground from the existing Harmon Substation to the future NCTS Finegayan Substation and on to the existing Andersen Air Force Base Main Substation. Design of all required electrical manholes, underground cables, fiber optic communications cable, circuit breakers, protective devices, cable terminations, and splices to construct the project are included in the scope of the design.