The QSN Link project connects the 935 km South West Queensland Pipeline (SWQP) with Epic Energy’s 780 km Moomba to Adelaide Pipeline and the 1,367 km Moomba to Sydney Pipeline.

The SWQP receives coal seam gas at Wallumbilla in Queensland, and transports that gas to Ballera to service the Mt Isa market, before continuing into South Australia to Moomba. The SWQP also delivers gas into the Roma to Brisbane Pipeline and the Queensland Gas Pipeline, utilising the gas hub at Wallumbilla.

The project included the construction of the 180 km, 400 mm diameter QSN Link, and a midline compressor station on the SWQP near Charleville and compression at Epic’s Wallumbilla compound.

Co-operative construction

In July 2007, Epic Energy set up an in-house project team to manage the QSN Link project. Headed by Daniel Wallace, the team of up to 12 people included both long-term Epic employees seconded to the project for its duration and contractors employed specifically for the project.

During construction of the pipeline and compressor facilities, around 300new jobs were created and Epic Energy employed additional staff to operate and maintain the new pipeline and facilities post commissioning.

BlueScope Steel supplied approximately 17,000 tonnes of high-strength PIPESTEEL, suitable for conversion into API 5L X70, to Orrcon's Pipe and Large Tube Division. The steel supplied was developed specifically to meet the stringent requirements of high-strength, high-pressure pipeline applications and has been used in over 20 other pipeline projects.

An early contractor involvement (ECI) process was adopted for the project, which enabled the construction contractor Nacap to become intimately involved in the planning and contract negotiation for the job prior to contract award. The ECI process also assisted the company to ‘hit the ground running’ once the contract was awarded.

Onsite cultural heritage monitoring continued while ground-breaking activities were underway in Queensland and onsite flora and fauna monitors were in place to ensure minimal impact on the natural habitat.

Construction of the compressor stations, at Scraper Station 4 near Charleville, and at Wallumbilla, commenced on 31 March 2008 and on 4 August 2008, respectively. All phases of construction being managed by Epic Energy were completed on time, for a mid-January 2009 first gas date.

Hot tapping the pipelines

Three hot taps were included on the project – a Class 900 tap on the SWQP, the Moomba to Adelaide Pipeline and on the Moomba to Sydney Pipeline. Nacap subcontracted the hot tap works on all pipelines to experienced hot tap contractor Furmanite.

Tight time-frames and environmental awareness

The main concern with respect to engineering was the fast track nature of the job. Again the co-operative nature of the project between Nacap, Epic Energy and engineering consultant WorleyParsons in Brisbane, meant that any issues identified during the process were resolved quickly and with minimal impact on the construction process.

There were literally hundreds of culturally significant sites identified by local indigenous groups during pre-construction surveys of the planned route. On mobilisation to site, Nacap immediately flagged these as ‘no-go’ areas for the duration of the project. The identification of these areas, as is usually the case, resulted in minor re-alignment of the pipeline route and reduced work space in areas where re-alignment was impractical.

The most environmentally significant sites on the project were identified early in the pre-construction surveys around the creek areas and, in particular, the Cooper Creek crossing near the Nappa Merrie bridge. Numerous planning visits were undertaken to the proposed Cooper crossing site by personnel including Nacap, Epic and environmental consultant, RPS Ecos, to ensure that the optimum route was chosen with minimal environmental impact.

Further expansion

Work continues on bringing the previously announced proposed Stage3 expansion of the SWQP to fruition. The Stage 3 expansion involves the construction of a new circa 935 km, 450 mm diameter pipeline adjacent to the SWQP. The expanded SWQP’s daily capacity would be increased from 168 TJ to approximately 380 TJ.