Bulga Underground Operations had pleaded not guilty to the offence under the Occupational Health and Safety Act after the incident at its Beltana coalmine on April 23, 2010.

The miner was knocked unconscious and was crushed between the toe of an automatically advancing roof support and the side of a continuous armoured face conveyor, the NSW District Court heard on Wednesday.

The worker was found semi-conscious on the ground with ‘‘severe’’ crush injuries and a large piece of roof stone lying across his thigh.

His helmet had been knocked off and he had no recollection of what had happened, Judge James Curtis said.

Just five weeks earlier another worker had been struck on the head and shoulder by a large piece of coal that was thrown towards him after it fell from the coal face while he operated a shearer.

There was also evidence that another miner had suffered crush injuries during an incident in 2008.

Bulga Underground Operations argued that the risk to the miner  in the 2010 incident was not foreseeable.

Judge Curtis disagreed.

‘‘Notwithstanding the matters raised ... I have concluded that the circumstances in which [the miner] came to be injured were foreseeable to a reasonable person standing in the place of the defendant,’’ he ruled.

‘‘The defendant failed to mitigate the foreseeable risk by taking the reasonably practicable measure of employing the services of an additional miner in the crew, whose sole task was to observe the drum operators and stop the advancement of roof supports if the drum operator became disabled.’’

The mine will be sentenced at a later date.