"The potential investment and returns for that investment are huge in this particular mine" says Wayne Thomas, from the National Union of Mineworkers.
"The access is already there, and the working methods could be adapted slightly.
"But the investment returns are there for the longer term, and I think there's stability there... for these individuals in South Wales who want to work in coal mining."
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Charities in Wales say thousands of low-income families with disabled children could be missing out on grants, because of government cuts.
Tuesday will have a murky start with widespread fog, mist and low cloud.
A plan to secure the future of Port Talbot steelworks will be unveiled to staff on Wednesday, ITV News understands.