Merthyr Vale Colliery was a coal mining facility above the town of Aberfan (Wales, England). For approximately 50 years, millions of cubic metres of debris from the mine had been deposited on the side of Merthyr Mountain. On October 21st, 1966, heavy rains brought a torrential flood of liquefied debris rushing down the mountain and into the town, killing 144 people; 116 of them were children.
Early on the morning of Friday, 21 October 1966, after several days of heavy rain, a subsidence of about 3–6 metres occurred on the upper flank of colliery waste tip No. 7. At 9:15 a.m. more than 150,000 cubic metres of water-saturated debris broke away and flowed downhill at high speed. It was sunny on the mountain but still foggy in the village, with visibility only about fifty metres. The tipping gang working on the mountain saw the landslide start, but were unable to raise the alarm because their telephone cable had been repeatedly stolen – although the official inquiry into the disaster later established that the slip happened so fast that a telephone warning would not have saved any lives.
The front part of the mass became liquefied and moved down the slope at high speed as a series of viscous surges. 120,000 cubic metres of debris were deposited on the lower slopes of the mountain, but a mass of over 40,000 cubic metres of debris smashed into the village in a slurry 12 metres (40 feet) deep.
The slide destroyed a farm and twenty terraced houses along Moy Road and slammed into the northern side of the Pantglas Junior School and part of the separate senior school, demolishing most of the structures and filling the classrooms with thick mud and rubble up to 10 metres (33 feet) deep. Mud and water from the slide flooded many other houses in the vicinity, forcing many villagers to evacuate their homes.
The pupils of Pantglas Junior School had arrived only minutes earlier for the last day before the half-term holiday. They had just left the assembly hall, where they had been singing “All Things Bright and Beautiful”, when a great noise was heard outside. Had they left the assembly for their classrooms a few minutes later the loss of life would have been significantly reduced, as they would not have reached their classrooms when the landslide hit: the classrooms were on the side of the building nearest the landslide.
Nobody in the village was able to see it, but everyone could hear the roar of the approaching landslide. Some at the school thought it was a jet about to crash and one teacher ordered his class to hide under their desks. Gaynor Minett, then an eight-year-old at the school, later recalled:
“It was a tremendous rumbling sound and all the school went dead. You could hear a pin drop. Everyone just froze in their seats. I just managed to get up and I reached the end of my desk when the sound got louder and nearer, until I could see the black out of the window. I can’t remember any more but I woke up to find that a horrible nightmare had just begun in front of my eyes.
After the landslide there was total silence. George Williams, who was trapped in the wreckage, remembered:
“In that silence you couldn’t hear a bird or a child”.
After the main landslide stopped, frantic parents rushed to the scene and began digging through the rubble, some clawing at the debris with their bare hands, trying to uncover buried children. Police from Merthyr Tydfil arrived soon after and took charge of the search-and-rescue operations; as news spread hundreds of people drove to Aberfan to try and help but their efforts were largely in vain. A large amount of water and mud was still flowing down the slope, and the growing crowd of untrained volunteers further hampered the work of the trained rescue teams who were arriving. Hundreds of miners from local collieries rushed to Aberfan, especially from the nearby Merthyr Vale Colliery, as well as miners from Deep Navigation Colliery and Taff Merthyr Colliery in the neighbouring Taff Bargoed Valley, and also from pits across the south Wales coalfield, many in open lorries with their shovels in their hands, but by the time those miners reached the site there was little they could do. A few children were pulled out alive in the first hour, but no survivors were found after 11 a.m. that day.
By the next day (Saturday) some 2,000 emergency services workers and volunteers were on the scene, some of whom had worked continuously for more than 24 hours. Rescue work had to be temporarily halted during the day when water began pouring down the slope again, and because of the vast quantity and consistency of the slag it was nearly a week before all the bodies were recovered.
Bethania Chapel, 250 metres from the disaster site, was used as the temporary mortuary and missing persons bureau from 21 October until 4 November 1966 and its vestry was used to house Red Cross volunteers and St John Ambulance stretcher-bearers. The smaller Aberfan Calvinistic Chapel was used as a second mortuary from 22–29 October and became the final resting-place for the victims before their funerals.
Two doctors were given the job of making death certificates and examining the bodies; the causes of death were typically found to be asphyxia, fractured skull or multiple crush injuries. A team of 400 embalmers arrived in Aberfan on Sunday and under police supervision they cleaned and prepared over 100 bodies and placed them in coffins obtained from South Wales, the Midlands, Bristol and even Northern Ireland. The bodies were released to the families from the morning of Monday 24 October. Due to the cramped conditions in the chapel/mortuary, parents could only be admitted one at a time to identify the bodies of their children. One mother later recalled being shown the bodies of almost every dead girl recovered from the school before identifying her own daughter.
The final death toll was 144. In addition to five of their teachers, 116 of the dead were children between the ages of 7 and 10 – almost half of the children at the Pantglas Junior School. Most of the victims were interred at the Bryntaf Cemetery in Aberfan in a joint funeral held on 27 October 1966, attended by more than 2,000 people.