In February 2002, Oil Company of Australia Ltd (now APLNG; a joint venture between Origin 37.5%, ConocoPhillips 37.5% and Sinopec 25%), acquired a number of CSG interests from Tri-Star that are subject to reversionary rights and an ongoing royalty in favour of Tri-Star. Upon a reversion trigger, APLNG are required to transfer back to Tri-Star a 45% interest in those CSG interests for no additional consideration. The reversion trigger is taken to have occurred when APLNG’s revenues and all other benefits from the CSG interests exceed the costs of developing the CSG interests, plus interest and royalties.
Today, the CSG interests that Tri-Star discovered supply significant feedstock to the 2 train APLNG LNG Plant on Curtis Island in Gladstone. The gas that Tri-Star has a right to after reversion represents in excess of 22.5% of APLNG 2P reserves as at 30 June 2018.
In addition to the above, Tri-Star hold a 0.75% and 0.0375% working interest in the Durham Ranch and Spring Gully joint ventures, respectively, operated by APLNG.
Between 2004 and 2006, Tipperary Corporation and Bronco Energy (now GLNG; a joint venture between Santos, Total, PETRONAS and KOGAS) acquired several CSG interests from Tri-Star, including Fairview, Arcadia and Roma East, in exchange for an ongoing royalty in favour of Tri-Star.
The above assets are some of the most prospective CSG fields in the world and have underpinned the A$80 billion CSG to LNG industry in Queensland.
Durham Ranch & Spring Gully
Durham Ranch is a joint venture between APLNG, Santos, AGL Energy and Tri-Star. The field is located on the western edge of the Bowen Basin in Queensland and is effectively the southern extension of GLNG’s Fairview field, operated by Santos.
First commercial production commenced in 2005 under APLNG’s operatorship. Development continues to be phased with approximately 409 development wells online. Exploration and appraisal activities are ongoing.
Gas produced from the Durham Ranch field is processed at two in-field compression facilities (Spring Gully and Taloona) and two off tenement facilities (Strathblane and Eurombah Creek), which have combined processing capacity of 388 TJ per day. The field is well connected to the Wallumbilla Supply Hub by several pipelines including the 88-kilometre Spring Gully to Wallumbilla Pipeline operated by Jemena.
Combabula (also known as Reedy Creek) is a joint venture between APLNG and Santos located in the northern Surat Basin, 45 kilometres north east of Roma. Commercialisation of the Combabula resource continues to take place in phased developments with approximately 671 development wells currently in operation.
In-field facilities include two gas processing facilities (Combabula and Reedy Creek), with a combined capacity of 450 TJ per day.
Located in the Undulla Nose area of the Surat Basin, the Condabri field is wholly owned by APLNG. Approximately 613 development wells are connected to three upstream gas processing facilities (Condabri North, Condabri Central and Condabri South) with a combined processing capacity of 540 TJ per day.
Fairview is a world class CSG reservoir, which commenced commercial production in January 1995 under Tri-Star’s operatorship. Gas is processed at four upstream compression facilities with a combined capacity of 588 TJ per day. Current production is approximately 400 TJ/d with significant development activity still in the forward plan targeting a 15% growth in field well count.
Following a successful commerciality pilot, with production of approximately 10 TJ/d, full field development commenced in mid-2018. Approximately 136 wells are planned in the first phase, with sales gas to be processed at a 75 TJ per day upstream compression facility. A second phase of development is planned for 2021-2023.
Development of the Roma East field commenced in 2018 with first commercial production achieved in February 2019. First stage compression is via a 120 TJ per day in-field nodal facility with final compression occurring at GLNG’s Roma Hub. In excess of 400 wells have been sanctioned by Santos and its joint venture partners Total, PETRONAS, KOGAS and APLNG with a continuous appraisal and development program planned.