Santos

The company came about after Robert Francis (Bob) Bristowe (1904-1959) and John Langdon Bonython, who had been school friends in Adelaide, partnered with a team of geologists led by Reg Sprigg and Helmut Wopfner tasked with finding oil.

Santos was incorporated on 18 March 1954, with its name an acronym of South Australia Northern Territory Oil Search. Geologist and Antarctic explorer Sir Douglas Mawson, who was appointed to the inaugural board, was responsible for adding "Northern Territory" to the name. Mawson, who had been involved in some early exploration in the Coorong area (1938–1941) and retained a lifelong interest in petroleum geology, resigned very soon afterwards due to ill-health, becoming an honorary consultant to the company. The other inaugural directors were Bonython, who chaired the board; Bristowe; George William Symes; and Henry Simpson Newland. In 1957, the directors included John Jenkinson, Hubert Harvey, and Bob Bristowe.

The core business of the company was initially built on gas discoveries in the Cooper Basin, South Australia, with the discovery and development of the Gidgealpa 2 well in 1963 and Moomba 1 in 1966. It signed supply contracts with the South Australian Gas Company, the Electricity Trust of South Australia and the Australian Gas Light Company, commencing supply in 1969.

After oil was discovered at Tirrawarra, near Moomba, South Australia, in the early 1970s, the company developed its liquid supply operations, which included a plant at Moomba and a fractionation and loading facility at Port Bonython.

In the 1990s, the company expanded, acquiring other companies and developing its operations both onshore and offshore in Australia, Indonesia, Malaysia, Vietnam and Papua New Guinea. Also in this decade it acquired interests in petroleum in the United States and United Kingdom, as well as operations in the Timor Sea and Western Australia. The Ballera gas plant in South West Queensland was established in 1991 and upgraded in 1997.

In 2015 Santos began producing LNG, shipping it to South Korea.

In August 2018 Santos announced the acquisition of Australian oil and gas company Quadrant Energy for $2.15 billion. As part of the deal, Santos obtained Quadrant's 80% stake in Dorado in the Bedout Basin in northern Western Australia.

In May 2020 Santos completed its acquisition of ConocoPhillips' northern Australia and Timor-Leste assets for US$1.265 billion as well as a contingent payment of US$200 million, which gave Santos control of ageing offshore assets in Bayu-Undan, subsea assets in the Timor Sea, and onshore gas plant Darwin LNG (DLNG), which included the Bayu-Undan to Darwin Pipeline. At the completion of the deal with ConocoPhillips, the interest of Santos in these assets was increased to 68.4%, The sale was contingent on a final investment decision on the future #Barossa project, which once concluded increased Santos' interest in the project to 62.5%.

The South Australian and Queensland gas reserves are the main sources of natural gas to the eastern states of Australia. Santos is the primary venture partner and operator of natural gas processing facilities at Moomba in SA and Ballera in Queensland, and pipelines connecting those facilities with Adelaide, Sydney, Melbourne, Brisbane, Rockhampton and Mount Isa.

Gas and LNG

Santos has made significant discoveries in the Browse Basin, off the northwest of Western Australia. On 22 August 2014 the company announced a major gas condensate discovery at the Lasseter-1 exploration well in WA-274-P in the basin, in which Santos had a 30% interest in company with Chevron (50%) and Inpex (20%). It was the second major discovery by the company in the area in two years.

On 7 September 2017 Santos pledged to divert 30 petajoules of gas from the Gladstone LNG plant slated for export into Australia's east coast market in 2018 and 2019, as part of efforts to avert government-imposed restrictions on gas exports to solve local gas shortages. However, because of delays in developing its Narrabri coal seam gas project in NSW causing a shortfall in its own supply of gas for export, Santos instead relied on purchasing gas from the domestic market to supply its overseas contracts with Malaysia and South Korea. By 2025 wholesale gas prices had tripled on the Australian east coast market, leading to increased gas and electricity prices for retail consumers and threatening the viability of energy-intensive manufacturing industry. In December 2025 the Albanese government announced its plan to introduce a gas reservation policy, to take effect in 2027, forcing gas companies to reserve at least 15% of production for domestic use.

Santos has an interest in the Darwin LNG project, which was the first liquefied natural gas project in the Northern Territory and the second in Australia. It has been supplied by the Bayu-Undan field, which is anticipated will be exhausted during the 2020s, hence the intention to develop the Barossa project to replace the dwindling reserves.

Incidents

Moomba explosions, South Australia

On 1 January 2004 an explosion occurred at Santos' Moomba processing facility. The blast was traced to the Liquids Recovery Plant (LRP), where an inlet manifold and a related flange weld both failed after corrosion by mercury. Mercury was released along with a cloud of flammable gases including methane, ethane, propane and butane. Workers saw the cloud and raised the alarm, shutting down the plant and evacuating to designated safety points. Some workers allegedly did not hear the emergency alarms. The gas cloud ignited on contact with a heating unit 150 metres away, and an explosion followed. The plant was seriously damaged.

Moomba workers who sought to remain anonymous told The Australian newspaper on 5 January that the company was running a "cowboy" operation, and that it was luck, not management that had prevented any loss of life. They also said that the emergency muster area was too close to the plant in the event of a major tank explosion.

Gas supplies to South Australia and New South Wales were interrupted, leading to down-time in the manufacturing sector and short-term rationing measures in both states while repairs were made. Santos spent $40 million on remedial action following the incident. In 2011, the South Australian industrial relations court ruled that 13 employees had been placed at risk due to critical safety shortcomings. These included an inadequate risk assessment which failed to identify the likelihood of plant failing due to liquid metal rendering it brittle. The company pleaded guilty to breaching the Occupational Health Safety and Welfare Act after a SafeWork prosecution and was fined $84,000.

Sidoarjo mud flow, Indonesia

In May 2006, the Sidoarjo mud flow disaster occurred in East Java, Indonesia. Controversy exists surrounding the probable cause of the disaster which has displaced approximately 10,000 people and covered villages, farms and industrial areas with mud. The eruption is ongoing, though since 2011 the rate of flow has reduced.

Santos had stated in June 2006 that it maintained "appropriate insurance coverage for these types of occurrences".

Port Bonython groundwater contamination, South Australia

In May 2008, groundwater contamination was reported to the Environment Protection Authority (EPA) following detection at Santos' Port Bonython site, Spencer Gulf, South Australia. Hydrocarbons were found floating on and in the groundwater. One hundred and fifty inspection wells were later established, and a 450-metre-long (1,480 ft) cement bentonite wall was constructed 'to stop the further spread of contamination off-site' including to the marine environment. In May 2012, Santos reported declining rates of hydrocarbon recovery from groundwater extraction wells and claimed that their remediation efforts were working.