Research by the McKell Institute published last year found around $1 billion a year in economic activity was lost to mining regions including the Hunter Valley and Central Queensland due to the widespread use of lower-paid casual labour hire workers in the mining industry.

In many coal mines, half or more of the workforce is labour hire, rather than directly employed by the mine operator.

According to the mining union, labour hire contractors are generally casual and paid 30% to 40% less than direct, permanent employees, getting no paid or annual leave.

Construction, Forestry, Mining and Energy Union president Tony Maher said the IR Omnibus Bill before the federal parliament included an unfair definition of casual that was based purely on the label in the worker's contract, not the reality of work arrangements.

"And it includes weak, unenforceable casual conversion provisions that employers can easily ignore," he said.

"We urge senators not to pass the IR Omnibus Bill in its current form. We need real solutions to the casual labour hire rort in mining and we welcome Labor's strong policies to address it."

Labor is proposing "same job same pay" for labour hire workers and a fair definition of "casual", according to Maher.

"Workers have been speaking out loud and clear about this problem and it is well understood in mining regions, where families are left without the ability to secure home loans, take holidays together and build their lives in a way afforded by secure work," he said.

However, the Australian Mines and Metals Association believes the ALP's industrial relations policies contain significant additional costs and regulation for Australian businesses with little vision for encouraging investment and creating jobs during the nation's post-pandemic recovery.

AMMA CEO Steve Knott said ABS data clearly showed casual employment remained consistent at around one-quarter of the labour force for decades.

"In fact, the proportion of employees who currently receive paid leave entitlements at work is at a historic high of 77%, up from 74.5% in 2016," he said.

"In the resources and energy industry, 83% of employees are permanents and receive paid leave entitlements. While nobody wants to see people involuntarily locked into long-term casual employment, any claim this is rife in the resources sector or the broader Australian labour force is baseless."

Knott said nobody was trying to deny fair payment to employees who are found to have been misclassified as casuals and owed back-paid entitlements.

"But the notion that employers should have to back-pay entitlements on top of casual loading already paid in lieu of those same entitlements, is ludicrous," he said.

"Employees should be fairly paid, and employers should not have to pay twice. The government's IR reform bill applies this ‘fair go all round' principle while introducing new casual conversion rights to ensure employees are not locked into casual contracts when their work is permanent and ongoing."

Hogsback reckons this issue should be resolved fairly and once-and-for-all if the future of regional mining communities is to be assured.