The Rum Jungle uranium deposit was discovered in 1949 by a local prospector. It is 64 kilometres south of Darwin in the Northern Territory, on the East Finniss River.
In March 1952 the Commonwealth Government provided funds for setting up a mine and treatment plant to provide uranium oxide concentrate to the UK-US Combined Development Agency (CDA) under a contract which ran from 1953 to 1962. Rum Jungle was then the largest industrial undertaking in the Northern Territory. The Commonwealth, through the Australian Atomic Energy Commission (AAEC), was responsible for the mine, though management of it was on a contract basis (cost plus) by Territory Enterprises Pty Limited, a subsidiary of Consolidated Zinc Pty Ltd* set up for that purpose. A new town was built at Batchelor, a major wartime air base some 8 kilometres south of the mine.
* In 1962 Consolidated Zinc merged with the Australian interests of Rio Tinto Company Ltd to form Conzinc Riotinto of Australia Limited.
The White's orebody was initially developed underground, from 1950 to 1953. Production from White's open cut started in 1953 and the treatment plant commenced in 1954. White's was mined out to depth of over 100 metres in November 1958 and Dyson's open cut was mined in 1957-58. A little ore was mined in 1958 from Mt Burton open cut, 4 kilometres west of the plant. Ore from these was stockpiled and progressively treated, and was more than sufficient to complete the CDA contract.
Treatment plant - click to enlarge
Rum Jungle Creek South orebody some 7 kilometres south of the plant site and 3 kilometres west of Batchelor was discovered in 1960 by Territory Enterprises, but there was no sales contract for its uranium. However, in 1961 the Commonwealth Government decided to proceed with developing it. It was mined 1961-63 to depth of 67 metres, with the relatively high-grade (0.37% U) ore being stockpiled for treatment beyond the January 1963 expiry of the CDA contract. The product from this was to be offered on the open market or stockpiled at AAEC in Sydney until the market improved in the 1970s. In the event, about 2000 tonnes of yellowcake was thus stockpiled by the time the mine closed in 1971.*
* In 1994, 239 tonnes on Rum Jungle uranium oxide was sold to a US utility, leaving 1814 tonnes still stockpiled.
Up to mid 1962, when the offer expired, the AAEC also purchased some high grade uranium ore from other deposits for treatment at Rum Jungle. From 1954 to 1957 the Australian Uranium Corporation NL sold ore from its Adelaide River mine to AAEC, and in 1962 South Alligator Uranium NL sold some high grade ore from the Eva deposit near the Queensland border, 900 kilometres away, which yielded 6 tonnes of uranium oxide.
The uranium treatment plant used an acid leach and ion exchange process until 1962 when the latter section was replaced with solvent extraction and magnesia precipitation to treat the Rum Jungle Creek South ore. Tailings were released into a poorly engineered shallow dam initially and after 1958 were put into White's pit.
White's open cut and RJ treatment plant, late 1950s - click to enlarge
As well as uranium, mineralisation at Rum Jungle included copper and lead. Some ore from White's was treated to recover copper, and in addition the Intermediate orebody was mined to a depth of 68 metres in 1964-5 solely for copper by Australian Mining and Smelting Company Limited*, a subsidiary of Consolidated Zinc (later Conzinc Riotinto of Australia, later Rio Tinto). This necessitated the diversion of the East Finniss River. About 360,000 tonnes of mill grade ore at 2% or more copper was recovered with another 370,000 tonnes of leaching grade ore (0.7-2.0% Cu). The latter** was treated in heap leach from 1965.
*This AM&S is not the same as a later CRA company bearing the same name. ** The heap leach consisted of 260 000 t sulphide ore averaging 1.7% copper and 110 000 t oxide ore averaging 2.0% copper.
Rum Jungle treated 863,000 tonnes of 0.27-O.43% U3O8 ore to produce 3530 tonnes of U3O8, according to the most authoritative accounts, (along with 20,000 tonnes of copper concentrate from other ore). Others represent uranium oxide and copper concentrate as follows, though the uranium data and probably the copper refer to contained minerals rather than production:
Towards the end of the mine's life the AAEC undertook studies to identify the extent and degree of environmental damage and likely sources of pollution. However, on completion of mining in 1971 it was decided by the Commonwealth Government that funds should not be made available for any rehabilitation, so the area was simply left.
Within a few years the Rum Jungle mine had become one of Australia's most notorious pollution problems, due to oxidation of sulphides by bacteria and the consequent release of acid and metals into the East Finniss River. The monsoonal climate and 1500 mm rainfall coupled with the pyritic mineralisation in the area created ideal conditions for such processes (which of course were harnessed, without commercial success, in the copper leaching operation).
White's overburden/ waste dump - click to enlarge
Intermediate overburden/ waste dump - click to enlarge
Tailings dam, with plant site and White's pit beyond - click to enlarge
An initial attempt to clean up Rum Jungle was made in 1977, which led to the setting up of a working group to examine more comprehensive rehabilitation. A A$ 16.2 million Commonwealth-funded program got under way in 1983-88. A supplementary A$ 1.8 million program to improve Rum Jungle Creek South waste dumps was undertaken in 1990-91.
Intermediate pit and waste dump, White's pit and plant site beyond, Dyson's top right, 1986 - click to enlarge
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