It is “difficult” to give a “cast iron guarantee” that lives won’t be lost because of a coal tip disaster, the deputy first minister of Wales has told Sky News.  

Nearly 60 years since the Aberfan disaster, which killed 144 people when coal waste slid down the side of a mountain into a school, £130m has been invested in securing waste left behind by coal mining operations.

Earlier this year, the Welsh government said up to £600m could be needed to secure coal tips across the nation.

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Olivia White, who lives beneath a disused coal heap in Cwmtillery that has been deemed a potential risk to public safety, says she is living with “horrific fear every day, waking up thinking we’re lucky we’re here again today”.

Ms White’s home was one of around 40 evacuated when part of the coal tip collapsed last year. She says she will never forget opening the door and “thick, dirty sludge pouring through”.

She warned: “I think it is going to take somebody to die or something awful to happen until they realise how serious this is. That’s what it feels like. Aberfan just lingers over me all the time”.

Her neighbour, Zara Cotterell, says it was “very lucky” that children weren’t playing outside at that time.

She says: “It was 7.30pm, if it was 5.30pm the street above would have had all the children playing; it took a car, it took a garage, it would have taken lives.”

Work is under way to secure the tip at Cwmtillery, which could collapse again, but both women say they feel “no one is listening” to them.

There are 2,573 disused coal tips across Wales, 360 of which are categorised as having a potential impact on public safety.

Deputy First Minister Huw Irranca-Davies says he can give people an “absolute guarantee” that no expense is being spared to fix the problem.

However, he said it is “pretty difficult” to give a “cast iron guarantee” that people are safe.

“It’s an almost impossible question,” he said.

Mr Irranca-Davies said the Welsh government has spent the last five years assessing which tips are the most high risk and work is starting to secure them.

He added that the £600m figure is a long-term goal to totally clear the tips, not all of which are high risk.

In the autumn budget, the UK government provided the Welsh government with £25m for essential work on disused coal tips. The Welsh finance minister Mark Drakeford is seeking a £91m commitment over three years from Westminster.

Mr Irranca-Davies says it is “great” that “after years of asking” there has been a contribution from the UK government.

Wales Secretary Jo Stevens says she wants people to feel reassured that coal tips are being inspected regularly and the “significant sum of money” given in the autumn budget will deal with the risks.

Plaid Cymru says the £25m from Westminster falls short of what should be paid, adding that Wales “can’t afford to wait for a tragedy to happen”.

Delyth Jewell, a member of the Senedd for South Wales East, says the coal tips are “ticking time bombs” and “Westminster should be paying to clear these tips”.

“Money, it’s not a question of [it] should be found. Money has to be found because this is correcting a historic injustice that should never have happened,” she said.

“And if they can’t prioritise clearing the coal tips in the valleys, who do they even represent? Who do they stand for?

“The legacy of Aberfan hangs over these communities.”