Published: 18 Sep 2018
The 19th & 20th of September are memorable in Queensland for the shock caused by mine explosions at Mount Mulligan (1921) and 54 years later at Kianga (1975).
On 19 September 1921 a massive explosion killed 75 mineworkers at Mount Mulligan. It was Queensland's biggest industrial disaster.
Mount Mulligan is 170kms west of Cairns. Coal mining supported the town from 1914 to 1958. Until then, the town did not even have a cemetery.
A rescue effort which began immediately after the explosion and continued for 5 days was fruitless.
The cause of the explosion was never determined beyond doubt, despite a Royal Commission. However, of several theories advanced it seems likely that the firing of an explosive on top of a block of machine cut coal, not placed in a shot hole, initiated the disaster. It is also recorded that dust levels were extremely high, providing a highly combustible atmosphere. Procedures for handling of explosives at the mine were lax, there was little in the way of stone dusting and watering, and it had been over 5 months since the last inspection by the Mines Department.
The Mt Mulligan disaster paved the way for a separate Coal Mining Act in Queensland. The 1925 Act provided for:
On 20 September 1975 a thunderous explosion tore through the underground mine, killing 13 men.
On an early morning inspection, Deputy Bill Allison detected signs of heating, which were reported to the manager. It was decided to establish seals and a full day shift was spent on this task.
In the afternoon a shift of volunteers was brought in to continue the work. A time after the start of the afternoon shift people on the surface found the sky blotted out by a vast cloud of dust. An enormous force tore the roofed walkway to bit, shattered the fan house and hurled a car 30 metres. The explosion could be heard in Moura, 27 kilometres away.
Tests taken after the explosion showed that the air underground was lethally toxic, with a temperature of at least 1000 degrees Centigrade. There was no hope for any of those underground. With a clear danger of further explosions, the decision was made to seal the mine.
Australia wide people wanted to help, and a fund for assistance to victims’ families was established.
Following Kianga, further legislative changes were made that saw:
• the introduction of explosion proof barriers
• a requirement for a barometer to be available on the surface of each underground mine
• a requirement for the provision of continuous carbon monoxide monitoring and recording of gas ratios and trends
• requirement for the construction of preparatory seals to enable rapid sealing of undergroun sections in the event of a heating or fire.