Nifty Pipeline Project: a collaborative effort

The Australian Pipeliner — July 2006

Working collaboratively with all stakeholders, McConnell Dowell drew on its pipelining experience in this harsh region of Australia to deliver the Nifty Pipeline Project on time and on budget.

The Nifty Pipeline Project involved the construction of a 45 km, six-inch gas spurline from the Telfer Gas Pipeline to the Birla Nifty Copper Mine in the Great Sandy Desert, Western Australia. This new supply of natural gas is used for on-site power generation requirements at the Nifty Copper operation.

Scope

McConnell Dowell’s involvement with the project commenced in 2004, when the company began assisting its client GasNet and end user Birla Nifty with budget pricing and technical support required for project sanction.

The arrival of Cyclone Fay complicated the initial planning and pricing phases of the project. Heavy rains inundated the region and resulted in severe flooding along the proposed pipeline route. Jointly, the GasNet/McConnell Dowell team decided on a new alignment, skirting flood impacted areas and taking the opportunity to minimise the number of difficult dune crossings.

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Once the project was given the green light, McConnell Dowell was awarded an Engineering, Procurement, Construction and Commissioning contract by GasNet. The contract scope also included responsibility for gaining all regulatory approvals required to introduce hydrocarbons into the pipeline.

A collaborative engineering effort

Upon award, engineering commenced immediately and encompassed the detailed design of the pipeline and the end-of-line facilities including SCADA control and telemetry. The telemetry provides remote control capabilities for the normally unmanned facility.

The detailed design was performed by McConnell Dowell’s in-house design team, who worked closely with GasNet personnel and were supported by Phil Venton & Associates for pipeline risk assessment and Peter Tuft & Associates for third party design validation. SCADA design was completed by CAMMS.

The pipeline comprised 45 km of 150 NB Class 600 pipeline. Grade X42 pipe with wall thicknesses of 5.2 mm & 7.11 mm were selected with a 600 micron dual layer FBE coating.

The end of line facilities comprised a takeoff station at KP 397 on the Telfer Pipeline. This station comprised a remotely controlled inlet isolation valve and scraper launcher pipework. Remote power was provided by solar panels and SCADA control via satellite. The receipt station at the Nifty Minesite comprised inlet isolation, filtration, metering, heating, pressure regulation and outlet isolation. A control hut was provided containing electrical and SCADA equipment with satellite communications to GasNet’s Dandenong and Boodarie control facilities. The experience of the team ensured that the Nifty system has integrated seamlessly with the existing Telfer control system.

The facilities were designed to be skid mounted where possible to minimise site installation works.

Procurement

The procurement scope comprised all items, both temporary and permanent, required to complete the project. Linepipe was supplied coated in triple random lengths ex. works by OneSteel/Bredero Shaw. Pipe transport was completed by Patricks who used a combination of rail to Perth and road to site.

Specialty piping items such as valves were ordered for delivery to Lightning Fabrication which was awarded the subcontract for pipe spooling and skid fabrication. Gasco provided the heaters, and CAMMS developed and delivered the SCADA system.

Environmental, health & safety

A requirement of the Pipeline Licence is the Construction Safety Case which was developed in conjunction with GasNet and approved by the Department of Industry and Resources (DoIR). Subsequent Commissioning and Operational Safety cases were also developed prior to introduction of gas.

The Environmental Management Plan developed by Birla Nifty required the pipeline to be installed prior to 31 October 2005. This stringent requirement was achieved ahead of schedule by fast track mobilisation and alignment of the project players Birla Nifty, GasNet, McConnell Dowell and the DoIR.

Fast-track construction

Pipeline construction was fast-tracked with the project team beating the scheduled completion date, despite encountering hard rock over the last 5 km of the alignment. McConnell Dowell used a direct hired workforce to deliver the construction, excluding NDT which was sub-contracted to RTD Steeltest. The McConnell Dowell team comprised a new generation of pipeliners, led by Ben Lyons and Chris Swaine in the office, and Troy Petith in the field.

Stringing was completed from bundled pipe utilising side booms, welding by MMAW, field joint coating was HBE 95, ditch was predominately by trencher and padding by OP 300 padder. Reinstate works were completed, including stabilisation works on the dune crossings, in November 2005. The cleared ROW has since revegetated extremely well assisted by the Pilbara wet season which runs from January to March.

It is worth noting that the DCVG survey conducted after the commencement of the wet season in 2006 resulted in zero defects, a tribute to the pipeline crew.

Stations construction was simplified onsite by the prefabrication of piping and skids as well as concrete supports. McConnell Dowell crews installed and pre-commissioned both inlet and outlet facilities.

Hydrotesting was performed by MACDOW High Level Test, the NATA approved testing arm of McConnell Dowell. The testing scope required drying to -20˚C dewpoint as well as a calliper pig run which was completed prior to introduction of gas.

Commissioning

Commissioning procedures were developed jointly by GasNet and McConnell Dowell. McConnell Dowell managed the commissioning with the assistance of GasNet operators. Prior to commissioning, a third party audit was performed by Steve Dykes to ensure the facility was ready for gas. Commissioning was successfully completed ahead of schedule and gas is now flowing to the Nifty Power Station.

Preserving the surrounds: environmental considerations

Minimising environmental impacts and ensuring conservation are key drivers in any pipeline construction project. For the Nifty project, one of the greatest challenges was to effectively manage the environmental impacts associated with the construction of a pipeline located in a remote area of the Great Sandy Desert. Issues relating to fauna management, disturbed area rehabilitation and dune stabilisation were of key concern. A range of environmental solutions were developed and implemented which met all regulatory requirements and also provided additional environmental data on the area for the scientific community.

To further understand the issue of fauna mortality, a specific fauna data management system was developed using best available technology. Daily retrieval of different fauna was carefully handled and the numbers, species and their status were all recorded. As a result, fauna data was successfully captured, verified and transmitted rapidly to stakeholders to verify effective implementation of fauna management measures.

Fauna mortality in open trench in an environment such as the Great Sandy Desert is mostly due to heat stress. To reduce the incidence of fauna mortality, specially adapted fauna shelters were placed in the open trench. The fauna shelters were constructed to provide a reduced ambient air temperature. Constant monitoring and measurements were taken during construction, which indicated that the intense solar radiation was reflected without increasing the air temperature within these shelters.

Another fauna management plan implemented was the Marsupial Mole Management Plan. In consultation with a Marsupial Mole expert, the plan was incorporated in the induction for all pipeline personnel that provided information on the species and illustrated individual responsibilities during the project.

Dealing with sand dunes was another area that required considerable attention. Dunes in the Nifty area are unconsolidated red sands with little cohesion and are typically only stabilised by vegetation. Disturbance of the vegetative cover has the potential to cause destabilisation of the immediate cleared area and the surrounds. Effective rehabilitation and stabilisation of disturbed dunes was achieved through rapid replacement earthworks such as landform reshaping, topsoil spreading, application of stabilisation agent and seed applications which in turn generated rapid revegetation in the area. A rehabilitation monitoring program was also in place post construction to evaluate environmental performances and to collect quantified data to measure the actual environmental impacts over time.

The commitment of the GasNet/McConnell Dowell team to innovative environmental practices has been highlighted with the project team being nominated for a Golden Gecko Award.

Appeared in issue: The Australian Pipeliner - July 2006 The Australian Pipeliner — July 2006