Activities on existing pipelines

Stretching for approximately 1,600 km from Karratha Gas Plant near Dampier to Clifton Road near Bunbury, the Dampier to Bunbury Natural Gas Pipeline (DBNGP) is the longest and one of the most important pieces of infrastructure in Western Australia. First commissioned in 1984, the mainly 660 mm diameter pipeline is interconnected with the Pilbara Pipeline System, Goldfields Gas Pipeline, Midwest Pipeline and the Parmelia Pipeline, with 300 km of laterals including Carnarvon, Geraldton, Neerabup and Pinjar.

In response to market demands from existing and new shippers, proponent Dampier Bunbury Pipeline has undertaken six expansion projects on the DBNGP between 1987 and 2010 – three over the last five years – with the most recent expansion, Stage 5B, being completed in April 2010. The result is that 84 per cent of the mainline has been duplicated.

The DBNGP system delivered a total of 325 PJ over 2009–10. Pigging of the mainline and loop line, as well as laterals, is scheduled during 2011–12, with planning and preparatory works having already commenced.

The first gas pipeline in Western Australia, the Parmelia Gas Pipeline, was constructed and commissioned in 1972 and stretches 416 km from Dongara to Pinjarra. The 355 mm diameter pipeline has a capacity of 70 TJ/d of gas and has two 203 mm laterals, which lead to the Perth gas fields and Kwinana Power Station respectively. It is also associated with the Dongara Processing Facility and Mondarra Gas Storage Facility.

The 353 km, 150–200 mm diameter Midwest Pipeline, which was completed in 1999, transports Carnarvon Basin gas via the DBNGP to power generators for mining processes in the Windimurra region. A 15 km lateral also connects to a gas-fired power station supplying electricity near Mt Magnet.

The 1,377 km, 350–400 mm diameter Goldfields Gas Pipeline is the second longest pipeline in Western Australia, stretching across more than two-thirds of the state. It supplies natural gas from the northwest of the state to mines in the Pilbara and Goldfields regions and in the last year, had a throughput of 41 PJ. The pipeline has been expanded over the last few years to meet additional customer demands. In 2009 two new compressor stations were constructed at Wyloo West and Ned’s Creek, increasing the pipeline’s capacity by 20 per cent.

APA owns and operates both the Parmelia and Midwest Pipelines, and has said that there has been a significant increase in enquiries regarding new or additional gas transportation requirements. APA also has an 88 per cent interest in Goldfields Gas Transmission, which owns the Goldfields Gas Pipeline. Alinta Energy Group holds the remaining 12 per cent interest and the pipeline is operated and maintained by APA.

Over the past decade the pipeline has delivered gas to new and existing mine sites, such as the Cosmos and Jaguar mine sites. Natural gas is a cost-effective alternative to diesel, which is commonly used as a generating fuel in remote mine sites.

APA is also considering an expansion of its Mondarra Gas Storage Facility, which is currently the only commercial underground gas storage facility in the state. The facility is located near Dongara and provides gas storage services to Parmelia Pipeline and DBNGP customers. Following strong demand for storage from customers, APA commenced assessment activities to expand the facility, from its current capacity of 3 PJ to around 12 PJ. The expansion work will commence in-line with customer contracts.

The 254 mm diameter Telfer Gas Pipeline is owned and operated by Energy Infrastructure Investments, an APA-established investment vehicle that both Marubeni Corporation and Osaka Gas hold a stake in. The pipeline was constructed and commissioned in 2004. It extends 476 km from the Epic Energy Compound located at Port Hedland to Newcrest Mining’s gold and copper mine at Telfer.

In 2005, a 46 km, 152 mm diameter extension of the Telfer Gas Pipeline to the Nifty gold and copper mine was completed, and in February 2011, it will be the first of the APA-operated pipelines to be pigged by APA’s new in-line inspection (ILI) vendor, GE . Other ILI projects scheduled for 2011 include the Parmelia Gas Pipeline in March, the Parmelia Kwinana Lateral in May, the Goldfields Murrin Murrin Lateral in April, and the Telfer Gas Pipeline later in the year.

Extending from the end of the Goldfields Gas Pipeline in Kambalda is the 340 km, 168 mm diameter Esperance Pipeline, which is 100 per cent owned by Infrastructure Capital Group’s Energy Infrastructure Trust. The pipeline, which was completed in 2004, has a designed capacity of 5.58 TJ/d of gas. At the time of writing, the pipeline was in the process of an intelligent pigging program.

The 219 km, 450 mm diameter Pilbara Pipeline was commissioned in 1996 and connects the Carnarvon Basin with mining operations in the Pilbara region as well as power stations located in Karratha and Port Hedland. Horizon Power connected to the system in 2009 through a 4.9 km, 200 mm diameter lateral and is now taking gas. The pipeline also has two other laterals: the 80 km Wodgina Lateral, which connects to the Sons of Gwalia tantalum mine at Wodgina, and the 24 km Burrup Extension Pipeline that connects the Pilbara Pipeline to Dampier.

Owner Epic Energy has said the Pilbara Pipeline is well positioned to take advantage of regional development in the future, having already received a number of enquiries relating to mineral processing opportunities which would be located along the pipeline’s length. Epic has also indicated that although it is currently a free-flow pipeline, the Pilbara’s capacity can be increased through compression and/or looping, making it flexible to meet future demand. The pipeline’s next pigging program is scheduled for this year.

Offshore developments

In the Carnarvon Basin offshore Western Australia, Apache Corporation’s approximately 65 km, 355 mm diameter East Spar Pipeline, which is currently mothballed, is due to be recommissioned in the second quarter of 2011 as part of plans to develop the Halyard Gas Field.

The Woodside-operated North West Shelf Venture (NWSV) project, transports gas and condensate from the Carnarvon Basin to shore via two pipelines. The North Rankin A Platform is connected to Withnell Bay by a 134 km, 1,016 mm diameter pipeline, which was completed in 1983. A second 134 km, 1,067 mm diameter pipeline was constructed in 2004 to meet additional capacity requirements to domestic markets.

In 1993, a 23 km, 762 mm diameter pipeline between the North Rankin A and Goodwyn A platforms was completed. Two years later, a 30 km gas export pipeline to the North Rankin A Platform from the Wanaea and Cossack fields was also constructed.

In 2007, production began from the Perseus and Searipple wells, with gas transported to the Goodwyn A Platform via the subsea 24.1 km, 406 mm Perseus-over-Goodwyn Pipeline. A 50 km subsea pipeline connecting the NWSV’s newest offshore gas production facility, the Angel Platform, to the first trunkline at the North Rankin A Platform was completed in the following year. The gas pipeline transports gas from the Angel gas and condensate fields to the onshore Karratha Gas Plant for processing.

In addition to Woodside, participants in the NWSV include BHP Billiton, BP, Chevron, Japan Australia LNG and Shell.

An abundance of LNG

Pipeline laying for Woodside’s Pluto Gas Project was completed in October 2009 by Allseas Construction Contractors, with JP Kenny contracted for engineering. A 27 km, 102 mm diameter monoethylene glycol (MEG) pipeline as well as two 508 mm diameter flowlines connect five subsea wells in the Pluto and Xena gas fields, located approximately 190 km northwest of Karratha, to an offshore processing platform. Gas is transported from the platform via a 180 km, 914 mm diameter trunkline, piggybacked by a 152 mm diameter MEG line, to a single 4.3 MMt/a LNG production train at the Burrup LNG Park.

Woodside’s is also proposing the Browse LNG Project, which will process natural gas from three fields – Brecknock, Calliance and Tarosa located in the Browse Basin, approximately 400 km north west off the coast of Broome.

The initial development concept for the project involves three floating gas and liquids platforms, a central gas processing facility and compression facility, and three processing trains with a capacity of up to 12 MMt/a of LNG. The project will involve 900 km of inter-field and in-field pipelines, and a 508 mm diameter condensate and 203 mm diameter MEG line piggybacking the main 315 km, 1,066 mm diameter gas trunkline, which will connect the central processing facility to shore.

Geotechnical studies are being conducted to understand pipeline route ground conditions and construction and stabilisation requirements, with the basis of design (BOD) phase approaching conclusion. JP Kenny is the BOD contractor for the subsea and pipeline scope. Front-end engineering and design (FEED) is expected to commence in early 2011 with operator Woodside planning to make a final investment decision in mid-2012. Other joint venture partners include BHP Billiton, BP, Chevron and Shell.

Further down the west coast of Australia is the proposed site for Chevron’s Wheatstone LNG Project. The initial phase of the Wheatstone LNG Development will involve a 250 MMcf/d domestic gas plant at Ashburton North and two processing trains with a total capacity of 8.6 MMt/a of LNG. A 220 km, 860 mm export pipeline will transport the gas from the field to the onshore gas plant while a second pipeline will be laid to allow future tie-ins from other gas fields.

The initial stage of the project will be underpinned by the Wheatstone and Iago gas fields, which are located approximately 200 km north of Onslow.

The company has applied for an additional three processing trains, which could bring the project’s total capacity up to 25 MMt/a of LNG.

Chevron’s joint venture partners for the Wheatstone LNG Development include Apache, KUFPEC and Tokyo Electric Power Company.

Chevron is also in the process of constructing the Gorgon LNG Development in a joint venture with ExxonMobil, Shell, Osaka Gas, Tokyo Gas and Chubu Electric. This project involves a 15 MMt/a LNG plant and a 300 TJ/d domestic gas plant on Barrow Island, off the northwest coast of Western Australia.

Gas will be collected from the Jansz and Gorgon fields located approximately 130–200 km off the northwest coast of Western Australia, which will be linked via a subsea pipeline to the northwest coast of Barrow Island. An underground pipeline will then transport the gas to three 5 MMt/a LNG trains on the island’s central-east coast for processing. LNG will be off-loaded from a 4 km long loading jetty for transport to international markets while compressed domestic gas will be delivered from the processing site at Barrow Island to the Western Australian mainland via a 90 km subsea pipeline, which would interconnect with the DBNGP.

Construction is well underway with more than $20 billion in contracts already awarded, including Technip and JP Kenny for upstream FEED, the Kellogg Joint Venture for downstream FEED, and Monadelphous for onshore pipelines. First gas is expected in 2014.

Other gas projects in progress

Apache and Santos’ Reindeer/Devil Creek Gas Project will develop the Reindeer Gas Field, located approximately 80 km off the Port of Dampier, via a wellhead platform located in 65 m of water. A single 110 km, 406 mm diameter offshore and onshore pipeline will transport gas from the platform to the Devil Creek Gas Plant for processing. The gas will then be exported to the Western Australian domestic gas market via the DBNGP.

The 15 km onshore component of the pipeline and the horizontal directional drilled (HDD) beach crossing have been completed, and laying of the 95 km subsea section of the pipeline began in early October 2010 with first gas expected at the end of 2011.

The Reindeer Gas Field will also be supplying Citic Pacific Mining’s Sino Iron Project located at Cape Preston, the largest planned magnetite project in Australia. The project involves a combined-cycle gas-fired power station that will be connected to the gas field via 13.5 km, 450 mm diameter pipeline. KT Pty Ltd completed construction of the pipeline in September 2009.

Western Australian Premier Colin Barnett has said that the State Government is committed to a Bunbury to Albany gas pipeline during its first term. The $255 million proposed pipeline – which is currently known as the South West Pipeline – is still in its planning stages.

The 200 mm diameter pipeline will run through Bridgetown and Manjimup, and is expected to carry approximately 50–100 TJ/d of gas. The State Government has allocated $10 million for both 2011–12 and 2012–13 in its state budget estimates.

In September 2010, BHP Billiton approved the Macedon Gas Project, which will involve the development of the Macedon Gas Fields located in the Exmouth Sub-basin approximately 100 km west of Onslow and 40 km north of Exmouth.

The project will involve four offshore production wells supplying a 90.5 km, 500 mm diameter wet gas pipeline to an onshore gas treatment plant to be constructed at Ashburton North. A 67 km, 500 mm diameter sales gas pipeline will interconnect with the DBNGP for sale to the domestic gas market. HDD will be used through coastal dunes. The project will also involve a shore crossing at Urala Station. The project is still currently in planning but first production is expected in 2013.

BHP and Esso Australia are considering piping gas from the Scarborough Gas Field, located in the Carnarvon Basin 300 km the coast of Western Australia, to an onshore LNG plant at Onslow. However, the project is still in the concept selection stage and the feasibility studies are continuing.

An unconventional future

Western Australian Department of Mines and Petroleum Executive Director Petroleum Bill Tinapple told The Australian Pipeliner that Western Australia has a number of unconventional gas prospects analogous to those recently discovered in North America which have yet to be drilled and/or have their production capacity demonstrated.

Unconventional gas includes coal seam gas (CSG), tight gas and shale gas. The main focuses for unconventional gas exploration in Western Australia are the Perth and Canning basins. “Although there is some potential for CSG,” Mr Tinapple said, “exploration companies are concentrating on tight gas and shale gas.”

When asked how he thought unconventional gas would impact on the pipeline industry, Mr Tinapple replied, “Most of the unconventional targets in the Perth Basin are near to existing pipelines. It is thought that although the grid would be expanded to bring these new gas supplies to consumers, new major transmission pipelines would not be required. However, for the Canning Basin, major transmission pipelines and interconnecting grids would be needed.”

Mr Tinapple described the unconventional gas developments in North America as a ‘revolution’, saying “There is no reason that similar developments won’t happen here. The trend has already started but is in early stages.”