Uranium was first found at a site halfway between Mount Isa and Cloncurry in 1954 by Clem Walton and Norm McConachy and the site was named for Norm’s wife who had died only two weeks earlier.
Walton and McConachy sold the mining rights to Rio Tinto who formed Mary Kathleen Uranium (MKU) Ltd to develop a mine and service town.
An architect-designed town grew during 1956-58, with reticulated water from Lake Corella.
A sales contract with the United Kingdom Atomic Energy Authority was signed in 1956 and MKU developed the project at a cost of $24 million.
Mining commenced at the end of 1956 and the treatment plant was commissioned in June 1958.
At the opening, Prime Minister Robert Menzies unveiled a plaque with Queensland premier Frank Nicklin.
In the first five years of its open-cut operation, MKU extracted 4080 tonnes of uranium oxide but in 1963 the major supply contract had been satisfied ahead of schedule, and large reserves of ore lay at grass.
The works were closed down until 1974, when Rio Tinto got new supply contracts with Japanese, German and American power utilities.
The company made a share issue to raise capital, and the Commonwealth Government, through the Australian Atomic Energy Commission underwrote this, obtaining a 42% holding in the company.
About 1200 people lived at Mary Kathleen in 1981. But by 1982 the mine was depleted and closed down after 4802 tonnes of uranium oxide concentrate had been produced in its second phase.
During the 12 years of operations about 31 million tonnes of material was mined, including 7 million tonnes of ore.
Mary Kathleen then became the site of Australia’s first major rehabilitation project of a uranium mine, completed in 1985 at a cost of $19 million.
All the buildings were carted away leaving the site empty.
The sign on the gate at the Barkly Hwy entrance to the site says “Even though no buildings remain, the ghost town like atmosphere makes one wonder what this flourishing community would have been like”.
Only a few remnants of buildings remain. Everything was dismantled and auctioned off. A couple of buildings remain at Mary Kathleen Park in Cloncurry.
The original mine site still has the remains of the processing plant and site office as well as the open cut mine.
Nowadays the mine resembles a swimming hole and exudes a spectacular blue colour due to the washing of minerals from the mine walls.
According to scientists, uptake of radionuclides and heavy metals into vegetation are sufficient to raise concerns over cattle now freely grazing across the site.