Zinfra had teams up to 75 employees and sub-contractors working on a FIFO roster to deliver this significant project. Dugald River Mine site is located in the remote outback of northwest Queensland, approximately 85 kilometres northeast of Mt Isa. The mine is owned by MMG Dugald River (MMG).
Zinfra’s substation scope of services included the design, procurement, construction, testing and commissioning of the mine’s 220/11kV substation. Zinfra’s inhouse design team completed the civil, primary and secondary systems design, SCADA design and telecommunication design. Procurement of the power transformers, control building, steelwork, bus bars, protection panels and control panels was complex. Some items were sourced within Australia, and a number of longer lead items were procured from Europe and Asian countries.
Zinfra self-performed the substation construction including all services, steelworks, bus work, electrical installation, substation testing (including protection, SCADA and communications interfacing) and commissioning. The work for the civil foundations, specialised site assembly of 220kV circuit breakers and 220/11kV power transformers was subcontracted and managed by Zinfra.
The 63.4 kilometre 220kV transmission line connects the newly constructed 220/11kV substation located on the Dugald River mine site to the existing Energy Queensland (formerly Ergon Energy) 220kV Chumvale substation located 11km west of Cloncurry and approximately 64km south of the Dugald River mine site.
For maximum efficiency Zinfra utilised crews working concurrently. The leading crew’s task was to drill the holes for the 182 poles required, often in rocky, difficult terrain. The next team constructed and dressed the poles. The poles were delivered in three parts that needed to be aligned and clamped, then have their insulators attached. The 9.5 tonne steel poles were manufactured in China where Zinfra conducted Quality Control and supervised load testing prior to exporting the poles to Australia. The weight load testing ensured the poles could withstand load and their integrity in winds up to 180 kilometres per hour. The last crew erected the poles using large cranes, ready to receive their concrete foundation within a 24 hour timeframe to fix them in place. Zinfra completed helicopter conductor stringing in sections of approximately 21 poles.
This challenging project brought all of Zinfra’s capabilities to the fore – complex procurement and critical logistics management, working in a remote location, innovative construction methodology and working to stringent time-frames – to successfully deliver this significant, large scale, high profile project for its client.
Most importantly, the project was delivered to a high quality and with zero LTI or MTIs over approximately 58,000 working hours.