Edmund Richards, who worked for 40 years as a miner, shakes his head sadly as he gazes at one of the many disused coal tips at the head of the Rhondda Fawr valley in south Wales. “They’re on the move,” he says. “No doubt. From time to time, inspectors will come and have a look, and say all is fine, but everyone around here knows they are on the move, on the slide.”

It isn’t always easy to spot the tips in this craggy landscape decades after most of the mines closed. Often, they are cloaked in scrub and trees but Richards, 80, says everyone who lives nearby knows where they are and is worried about them. “They need to get on and sort them out once and for all,” adds Richards. “It’s only a matter of time before something terrible happens.”

The issue of what to do about Wales’s 2,500 disused coal tips is back on the political agenda after the Labour-led Welsh government published maps pinpointing 350 situated close to homes and communities that it fears could put people at risk in the event of a landslip.