For the 72 years between its opening in 1943 and its closure, the mine supplied sub-bituminous coal to fire power stations first in Adelaide then, from 1954, Port Augusta.

[3] The open cut mine operation extracted low-grade, sub-bituminous coal[4] that was transported 250 km by rail to power stations outside Port Augusta on the east side of Spencer Gulf.

The coalfield at Leigh Creek was operated at first by the Electricity Trust of South Australia then by Alinta Energy, and produced over 2.5 million tonnes a year of coal.

Alinta energy also operated the power stations at Port Augusta; they were the last coal-fired electricity generators in South Australia, and the only users of coal from Leigh Creek.

No 1 shaft, sunk by the Leigh Creek Coal Mining Company, was abandoned on striking a heavy flow of water.

The combined A and B plants, with a total generating capacity of 330 megawatts, were named in recognition of the then South Australian Premier, Sir Thomas Playford.

[8]: 234 Although the line was built to handle coal traffic, Marree provided an advantage of moving further north the point at which passengers to and from Alice Springs had to transfer between a modern, air-conditioned train (on the new standard gauge track) and the original Ghan (on the narrow-gauge CAR).

In 1987, the terminus of the Marree line was pulled back to Telford Cut, where a balloon loop was built to simplify train operations.

On 11 June 2015, Alinta Energy announced their intent to cease operating the Leigh Creek coal mine beyond March 2018, closing it along with the related Playford B and Northern power stations, and warned that closure would be sooner should business conditions worsen further.

This was achieved by battering the steep mine sides down to shallower angles, and covering any potential coal deposits with at least two metres of inert earth.