JUST after 9.15am on the morning of Friday, October 21, 1966, as pupils at Aberfan’s Pantglas Primary School settled in for their first lesson of the day, a coal tip crane-driver watched as a wave of liquid spoil poured down Merthyr Mountain towards the village below.
What happened next was one of the worst industrial disasters in British history, which claimed the lives of more than 140 people - most of them children.
Fifty-six years on, it remains a trauma from which South Wales Valleys towns have never truly recovered.
The Disaster
Around two hours before the tip collapse, a handful of men had arrived at Merthyr Mountain to begin work. They worked for Merthyr Vale Colliery, one of many coal and ironstone mines on the colossal South Wales coalfield - at that time the largest in the world.
The business of extracting coal produces an enormous volume of waste material – a mixture of soil, shale, crushed rock and bits of coal – and it was the job of these men to pile this waste into a tip, using a crane to pick up and empty the carts sent up from the colliery.
That morning, the cluster of workers walked the peak of tip 7 like they did every day, checking the track that carried their crane. They found that part of the tip had sunk, taking the track with it.
After coming up with a plan to make repairs, the men decided to go for a tea break before getting started.
One man, a crane driver named Glyn Brown, lingered behind.
His chilling account from the time reads: “I was standing on the edge of the depression.
“I was looking down into it, and what I saw I couldn’t believe.
“It was starting to come back up. It started to rise slowly at first… I thought I was seeing things.
“Then it rose up… at a tremendous speed.
“It sort of came up out of the depression and turned itself into a wave - that’s the only way I can describe it - down towards the mountain… towards Aberfan village… into the mist.”
The approximately 30ft black “wave” hurtled down the mountain at around 80mph, sweeping away a number of houses before burying Pantglas Primary School.
The ordeals of that day have been written and spoken about countless times – and dramatised by the Netflix series The Crown - but the depths of horror experienced by its young victims are still difficult to contemplate.
When one of the few children that survived, Jeff Edwards, was interviewed as an adult by the BBC, he recalled hearing a “thunderous noise” as his teacher began their maths lesson.
“The next thing I remember was waking up," he said.
"My desk was pinned against my stomach and a girl's head was on my left shoulder - she was dead.
“Because all the debris was around me, I couldn't get away from her.
“The image of her face comes back to me continuously.”
Mr Edwards, then eight years old, was trapped for more than two hours, struggling to breathe as he listened to the cries and screams of his classmates.
"As time went on they got quieter and quieter as children died,” he added.
“They were buried and running out of air.”
Jeff was pulled out of the wreckage around 11am. He was the last child to be found alive.
In all, 28 adults and 116 children died. Their suffocated bodies were dug out of the sludge over the course of the next few days by local men - young and old, many of them related to the children - who used shovels, diggers and their bare hands.
Most of the victims are buried at Bryntaf Cemetery, where their graves are marked with distinctive white granite arches. A memorial garden was built on the former site of Pantglas school, which was officially opened by Queen Elizabeth and Prince Phillip in the seventies.
Jeff Edwards, meanwhile, decided he would never have children.
“Your personality has changed to such a degree - your traits, your make-up, your being has been so fundamentally altered, you wouldn’t want to perpetuate it,” he said.
The Failures
A number of spoil tips had taken shape on Merthyr Mountain since the colliery opened in 1869, but by 1966 just one was still in use – tip 7 - and like some of its disused companions, it sat on a natural spring of water.
It was this water, as well as the days of heavy rain that led up to the disaster, which caused the tip to slide.
“The initial line of the National Coal Board was that the disaster was caused by a natural spring appearing within the tip,” says coal industry historian Dr Ben Curtis.
“They said that, as far as they knew, no watercourse existed on the site before the tip was started - that they’d never known anything like this before.
“But that wasn’t the case.
“The springs were on an Ordnance Survey map in 1919, and on a geological survey map in 1959.”
The National Coal Board was a government body set up to manage the UK’s coal mines when they were nationalised in 1947, shortly after World War Two.
Despite the NCB’s apparent shock, there had been plenty of warning signs in the years before the tip collapse.
Dr Curtis explains: “There’d been a tip slide further down the Valleys, Cilfynydd way, in December 1939, which blocked the roads.
“The Aberfan tip itself was reported to have shifted in both 1959 and 1963, as well.”
The Valleys’ geography, he says, with its tips piled on steep hillsides and its towns largely nested in the valley floor, makes it particularly vulnerable to landslides - where coalfields in the Midlands and the north of England were not.
The 1939 landslide in Cilfynydd, just five miles from Aberfan, was extremely serious. More than 160,000 tonnes of spoil had slid, blocking the main road, the railway track, the Glamorgan Canal and the Taff River.
An engineer wrote a memo at the time warning about the risk of further tip slides, and making a number of safety recommendations. The report was apparently “put in a drawer and forgotten until 1965”.
A Merthyr town clerk had written to the Coal Board around 1959, requesting a meeting about the risk posed by the Aberfan tips. In 1963, tip 7 itself slipped, and it’s likely that this movement contributed to the disaster of 1966.
Despite complaints that specifically referenced risks to the Pantglas School, almost nothing had been done.
“The regulatory regime that had grown up around the coal industry didn't really take coal tips as an issue,” says Curtis.
“A lot of the focus was on safety in the mines underground - that kind of thing.
“The National Coal Board didn’t have a formal policy on tips because there wasn’t one in the industry in general.
“Extraordinarily, under the provisions of the Coal Mines and Quarries Act 1954, the Aberfan Disaster wasn’t technically a reportable incident, because it didn’t affect the colliery, and no colliery employees were injured.”
The Aberfan Disaster Tribunal, set up to examine the circumstances of the incident, laid the blame squarely at the Coal Board’s door, but cast its failures as one set in a history of neglect.
The tribunal worked remarkably quickly, and its final report was published less than a year after the disaster took place.
The report, a startling document to this day, condemned the disaster as “a terrifying tale of bungling ineptitude by many men charged with tasks for which they were totally unfitted, of failure to heed clear warnings, and of total lack of direction from above.”
The Trauma
The psychological wounds of Aberfan have expanded far beyond those original victims, says Dr Curtis.
“These were unspeakably horrific events that occurred, and it's something which still continues to resonate very powerfully with people, not just in the immediate community affected, but with people throughout the coalfield,” he added.
“I think this explains the nature of public response to the slip in Tylorstown last year.”
There are more than a thousand spoil tips still scattered around Wales, and the enormous mounds still make up a significant portion of the Valleys landscape.
Following Storm Dennis in February 2020, which saw dozens across Rhondda Cynon Taff flooded out from their homes, a section of a Tylorstown tip collapsed into an unoccupied ravine as anxious locals filmed on their phones.
Nobody was hurt, save for some trees and pylons, but minds immediately turned to Aberfan and questions about the safety of the Valleys’ tips began in earnest.
“It’s a really visceral sense of horror,” Dr Curtis adds.
“That image, of the land slipping like that - it taps into the, sort of, folk memory of the area.
“For generations that have grown up since then, the slightest inkling that an Aberfan could happen again is just too much.
“The south Wales landscape was literally reshaped in the image of the coal industry, in many respects.
“The industry’s gone, but its legacy is still there - it was a really shocking reminder.”
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