The conviction related to an incident on June 8, 2019, when a labour-hire worker's foot became trapped in an energised scraper conveyor after he was installing it at the underground mine.

He managed to forcibly pull his right foot out of the scraper conveyor, according to facts outlined in the court judgement.

As a result, the worker suffered severe crush injuries to his right foot, including a complete laceration of the sole and the amputation of several toes.

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The worker, in a victim impact statement, said he had lost a career and any prospects of future employment due to the injury.

The NSW Resources Regulator undertook an investigation following the injury.

EC, owned by South32, was convicted for failing to ensure the health and safety of workers when it exposed them to the risk of serious injury or death.

The company appeared before the NSW District Court on July 27 where it pleaded guilty to breaching the Work Health and Safety Act 2011.

On Wednesday, Judge David Russell handed down a fine of $300,000, which was reduced by 25 per cent to reflect the early plea entered by EC.

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The company was also ordered to pay the prosecutor's costs.

The Resources Regulator's executive director, Peter Day, said the court's decision emphasised the importance of workplace safety.

"This incident highlights the need for operators to ensure that all plant is subject to operational risk assessment," Mr Day said.

"Our investigation identified there were poor management and controls in place at the colliery, coupled with a poor handover to new team members.

"A number of documented systems of work designed to protect against the risk which eventuated were not implemented in practice."

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