The orebody was discovered in late 1969, and the mine commenced operation in 1980, reaching full production of uranium oxide in 1981 and ceased stockpile processing on 8 January 2021.

Uranium mined at Ranger was sold for use in nuclear power stations in Japan, South Korea, China, UK, France, Germany, Spain, Sweden and the United States.

[4] The Ranger uranium orebody, the richest in the southern hemisphere, was discovered in late 1969, when an aerial radiometric survey conducted by Geophysical Resources Development Co., a company based in Sydney, on contract to Noranda Aluminum, detected a large spike in gamma radiation when passing over Mount Brockman, known as Djidbidjidbi to the Mirarr traditional owners of the area.

The instrument that detected the anomaly was a Nuclear Enterprises gamma ray spectrometer using a Thallium doped Sodium Iodide cylindrical crystal.

The crew members on board were Bill Hay, the pilot, Harvey Morton, the navigator and Frank Lanza, the instruments operator, who first recognised the significance of the anomaly.

3 ore bodies occur in the Cahill Formation, consisting of Lower Proterozoic metasediments, located in the Alligator Rivers Uranium Field.

The name 'Ranger' for the series of discoveries made by Geopeko, the exploration arm of Peko-Wallsend, in the period 1969 to 1972, was thought up by Judy Ryan, the wife of the geologist in charge of the program.

In parallel with the construction of the exploration decline, ERA began a $57 million project to prepare a Prefeasibility Study into the potential development of a Ranger 3 Deeps underground mine.

[12] ERA formally commenced the statutory approval process for the proposed Ranger 3 Deeps underground mine in January 2013 with the submission of a referral to the Commonwealth Department of Sustainability, Environment, Water Population and Communities under the Environmental Protection and Biodiversity Control Act 1999.

[18] In 2012, ERA and the Mirarr traditional owners represented by the Gundjeihmi Aboriginal Corporation (GAC), conducted a jointly facilitated independent expert review of the quality of surface water around the Ranger Project Area.

The Independent Surface Water Working Group consisted of representatives from ERA, GAC, the Supervising Scientists Division and the Northern Land Council.

The working group agreed in findings released in March 2013 that the surface water management and regulatory systems in place at the Ranger mine were of a very high standard.

[19] Going forward, the Group agreed an action plan to ensure that surface water management systems at Ranger remained "best leading practice".

[20] In 2013, a spokesperson from the Public Health Association of Australia claimed that there had been a hundred safety incidents linked to the mine in the thirty years prior.

In May 2010, it was reported that a tailings dam may have released millions of litres of radioactive water into world heritage-listed wetlands in Kakadu National Park, home to about 500 Aboriginal people.

[21] On 7 December 2013 there was an incident at a mine site inside Kakadu National Park, with about a million litres of slurry, comprising crushed ore and acid, believed spilled, workers evacuated and production shut down.

[27][28] Ranger Uranium Mine is situated on the traditional lands of the Mirarr people of northern Australia and has been the subject of environmental and Aboriginal rights concerns.

[29] In addition to the environmental degradation caused by the mine, the Mirarr have also raised concerns about uranium from the site potentially contributing to nuclear accidents.

[30] Energy Resources of Australia (ERA), majority-owned by Rio Tinto Group, is legally required to rehabilitate the site to a condition suitable for inclusion in the World Heritage-listed Kakadu National Park.