The Kur-Ring-Gai STS project required Ultegra to operate as Principal Contractor inside the live sub transmission yard, installing a new foundation for the new capacitor bank, power cabling for the capacitor bank, 2x cable chases and 33kV feeder cabling to TX2. Large scale excavation was required in a live yard, with unknown cables and; in rock. A very complex project delivered safely, on time and to the highest of standards.
CORE REQUIREMENTS
- Demolition of existing footings requiring detailed earth grid and existing cable identification
- Construction of Capacitor Bank 1 footing (slab)
- Below ground earthing for Capacitor Bank
- Conduits for Capacitor Bank from basement wall
- Safety Fence and defined signage constructed
- Install 33kV Cu1 300mm cabling to Capacitor Bank 1
- Excavate and construct Cable Chases to TX1, 2 and TX 3 (up to ripple filter)
- Build temporary structures to divert existing in-service cabling facilitating cable chase construction
- Installation of 33kV Cu1 800mm cabling to TX 2 (including cleating and basement dressing)
- Design and installation of pre-cast cable chase lids
RESULTS
- Overcame multiple challenges related to existing site management to maintain construction program
- Owned our worksite as the Principal Contractor by delineating an Ultegra controlled work zone within Kur-Ring-Gai STS
- Agile management of multiple complex site issues including diversion of existing “in service” cabling
- Excavation in rock, around existing services in a live switchyard environment
- Exceptional community relations and stakeholder management
- Effective management of scope creep by daily tracking methods
CHALLENGES
- Over 200m3 of rock removed (up to 50mpA)
- Challenging process of rock removal around existing earth grids, power cables and control cabling in an aged switchyard environment
- Controlling a work area as Principal Contractor with Ausgrid and others working in the yard at any given time
- Installing 33kV cables through the basement in a planned and calculated manner by constructing temporary supports, rollers and cable pull plans
- Detailed lift plans in a live switchyard with live 33kV bus for crane and overhead lifting avoiding outages
- Management of Plant Movement Plans to ensure fluid worksite coordination was achieved