Reindeer Gas Field, Australia

Reindeer Gas Field is located in the permit area WA-209-P of the Carnarvon Basin, 45km southwest of Dampier, offshore northwest Australia. It is owned by Santos in a joint venture with Apache Energy in the ratio of 45% and 55% respectively. Apache Energy is the field operator.

Gas from the Reindeer field will be produced through an unmanned well head platform and transported to a new onshore facility at Devil Creek, via a 105km long pipeline.

The onshore gas plant will have a processing capacity of 210MMcf/d. The processed gas will be compressed and exported to the Western Australian domestic market through the Dampier-Banbury Natural Gas Pipeline.

The field is currently in the last stage of development, with production scheduled to begin in the fourth quarter of 2011. The $800m project will have a lifespan of 20 to 30 years. The production capacity of the field is approximately 110 tera joules (101 million cubic feet) a day of sales gas.

Apache Energy and Santos will sell the gas for the Sino Iron project of Chinese company Citic Pacific. The Sino Iron project is located in the Pilbara region and will be operational from the second quarter of 2012.

Reserves of natural gas at the site

The Reindeer gas field is estimated to have proven and probable reserves of 485 peta joules (446 billion cubic feet) of commercial gas and 1.6 million barrels of condensate as per 2008 exploration studies.

Development of the Reindeer gas field

Reindeer was discovered in October 1997. Santos commenced the front end engineering and design (FEED) in 2007 which was finalised and approved in 2008.

Three wells were drilled using the Ensco 106 jack-up. The project was however shelved in May 2009 due to the lack of a sales agreement.

It was resumed a month later after Santos and Apache signed the gas sales and purchase agreement with Citic Pacific.

Construction commenced in September 2009 after receiving all the necessary government approvals.

Infrastructure of the offshore site

The unmanned well head platform is built on a 1,200m² footprint. It weighs 1,700t and is 125ft tall. It is installed 65m deep under the water.

The substructure is a four legged jacket with one skirt file each. It has a four level topside processing module and a helideck integrated to the main deck.

The well head platform was installed in two phases. The jacket substructure with piles was installed first. The topside deck was installed on top of the jacket substructure later. The entire installation was completed in March 2011.

Pipeline running from the Australian gas field

About 90km of the total 105km length of the pipeline is laid under water and the remaining length is onshore to connect the processing facility. The offshore pipeline is laid 60m deep under the water and has a 2.5km section drilled horizontally at Gnoorea Point to link with the 10km onshore pipeline. The area occupied by the offshore pipeline is 89,000m².

The pipeline has been laid in two phases. The first phase included 23km of pipe installation in shallow water at a depth of five to 22m by the pipelay barge Leighton Stealth. Deep water laying was done in the second phase by the Sapura 3000 heavy lift vessel owned by SapuraAcergy.

Contracts awarded to companies

Santos awarded the contract for engineering, procurement and fabrication (EPF) of the well head platform to Perth-based Clough Engineering in June 2008.

The $200m contract involves transportation and construction of an unmanned well head platform and laying of a single gas pipeline. Clough Engineering deployed the Java Constructor vessel for the beach pull and Clough Challenge for the installation of pipeline.

Apache Energy awarded a $170m contract to SapuraAcergy for laying the offshore pipeline. Leighton was involved in laying the pipeline in shallow waters.

The horizontal directional drilling was completed by DrillTec in 12 weeks, commencing from February 2010.

DrillTec was assisted by ARV in the design, welding and health and safety issues. Geotechnical services and preparation of tenders, reviewing of documents and inputs for the environmental assessment were provided by Atteris.