In the car on the way home from a day out for mining families, the reality hit home for Brett and Melissa Slaney’s eight-year-old son.

“Our youngest son has a birthday this Thursday,” Melissa said.

“Driving home he said: ‘If dad doesn’t have a job, don’t buy me anything.’”

Melissa grew up as a coal miner’s daughter, and is proud to be a coal miner’s wife.

For the past eight-and-a-half years her husband Brett has worked at the Myuna Colliery on the Central Coast of NSW.

“That’s all I’ve known. As a child, teenager, as an adult is men that go off and do night shift down at the coal mines,” she said.

But now the Slaneys’ way of life and that of 300 other miners hangs in the balance over an ongoing dispute between Origin Energy and Centennial Mining.

The dispute centres around the imminent closure of the Origin Eraring Power Station, fed exclusively by coal from Myuna Colliery.

The life of the power plant was recently extended for another three years, giving hope to families and the local community who depend on it.

And for the miners at Myuna Colliery, Eraring isn’t just its only customer but the lifeline of the community.

Myuna Colliery is what’s known as a “captive mine”, meaning it exists solely to supply coal to Eraring.

Brett said without Eraring, the mine would be forced to close.

“Being a captive mine, we have nowhere else to go. We can’t continue mining and truck or train the coal out,” he said.

“We are solely reliant on that power station being open.”

Origin Energy has owned Eraring since 2013.

When the closure date of the power station was extended until 2029, Origin entered negotiations with Centennial, the operators of Myuna Colliery, on an end-of-life deal for coal supply.

On February 3, Origin offered up a 12-month agreement for coal supply from Myuna “maintaining terms consistent with the existing agreement”.

“Our offer enables the continuation of the long-term relationship between our organisations and supports ongoing employment for the Myuna workforce,” said Greg Jarvis, Origin’s head of energy supply and operations.

The offer was knocked back by Centennial, which pointed to the extended life-span of the power station and the intertwined nature of Myuna Colliery as part of its operation.

Two days later, Origin tabled a second end-of-life agreement saying it had “continued to engage openly, constructively and in good faith with Centennial”.

“We have now tabled two offers this week, with our latest proposal responding directly to Centennial’s request for an end-of-life agreement,” the company said on February 5.

“Our offer is on consistent terms to today, as we cannot meet Centennial’s elevated pricing demand which is forecast to be around $50 million per year above market levels. Over three years, we forecast this is ~$150 million above the cost of coal from other suppliers.

“The cost of operating Myuna is a matter for Centennial and its parent company, Banpu, a company of substantial size and profitability. Origin and NSW households and businesses cannot be expected to wear those costs.”

The February 5 offer from Origin was then rejected by Centennial, which claimed it would lose $1 million a week if it accepted the deal.

“Centennial acknowledges Origin’s tabling of a three-year end-of-life coal supply offer and welcomes the movement after months of delay, but the proposal still falls short of what is needed to keep Myuna Colliery open,” a spokesperson said.

“Origin cannot claim that a fair deal would hurt consumers. The company posted $1.5 billion in profit last year and Eraring is one of its strongest revenue-generating assets.

“Eraring power station and Myuna Colliery operate as a single, integrated supply chain that underpins energy security in NSW. Trying to separate them is not a transition plan.

“Under Origin’s current offer, Myuna would continue losing around $1 million a week while the financial upside flows straight to Origin, reflected in rising profits. That is not a sustainable arrangement for workers, communities or Myuna.

“Myuna is not asking for any profits. It is offering a break-even agreement that allows coal supply to continue through to Eraring’s scheduled closure in 2029, protecting 300 direct jobs and thousands more across Lake Macquarie and the Hunter.

“This is a practical, orderly outcome. Anything less shifts risk onto workers and households while Origin’s balance sheet remains protected.”

While the two companies work to come to an agreement, the hundreds of miners waiting for certainty around their own future say they’re living in a constant state of anxiety.

“In the last week we haven’t slept well, everything’s so expensive at the moment, it’s really stressful,” Melissa said.

The Slaneys said they would be forced to leave the community or look for FIFO work somewhere else in Australia if the companies can’t agree.

Brett said he was struggling with the potential reality of leaving his family to find work away from the Central Coast.

“Honestly, it just makes you sick to your stomach. Thinking about having to leave two young boys and their mother,” he said.

“They’re going to miss their father for half the year, their husband for half the year. Not being there when they need you, it makes you sick to your stomach.”