On the morning of the 21st October 1966, the Welsh mining town of Aberfan was bustling with activity. Schoolchildren hurriedly took their seats as classes began while life in the village carried on as usual.
Then disaster struck.
From the nearby Merthyr Vale Colliery a torrent of slurry surged downhill, cascading into the village in waves up to 30ft high. This avalanche of dirt and debris destroyed houses, swallowed streets and engulfed the Pantglas Junior School – which by this point sheltered more than 200 pupils.
In total, 144 people were killed in the Aberfan Disaster, 116 of which were children. At the school, which bore the brunt of the avalanche, 109 children and five teachers were killed while nearly 20 homes were destroyed.
Stunned by the sudden crash, rumble and deafening sound of the avalanche, the people of Aberfan regained their senses and began searching for loved ones and neighbours. Efforts to rescue survivors and retrieve the bodies of the dead lasted more than a week.
To this day, the Aberfan incident remains one of the worst disasters in British history, and at the time struck the hearts of millions across the country. So what caused the disaster?
The night before
On the evening of the 20th October, Aberfan was hit by heavy rain. Nearby, the Merthyr Vale Colliery spoil tip housed atop a mountain had taken on a significant volume of water following several weeks of heavy rain.
This build-up of water began to liquefy the waste materials held at the tip turning it into a volatile slurry which eventually began slipping downhill toward the village.
Notably, maintenance and monitoring of the spoil tip was the responsibility of the National Coal Board (NCB). At the time of the disaster, this particular spoil tip stood at 111ft high and sat on ground from which water springs emerged.
Reaction to the disaster
The disaster struck headlines across the UK, and indeed the world. A relief fund was established by the mayor of Merthyr Tydfil, which eventually helped raised more than £1.75 million for families affected by the disaster.
On 2nd November, an inquiry into the cause of the disaster was launched, led by Lord Justice Edmund Davies. Lasting more than two months, the inquiry considered evidence from more than 100 witnesses, and ruled that the National Coal Board (NCB) was responsible for the incident.
The inquiry outlined several key recommendations to prevent a repeat of the Aberfan Disaster. In particular, these included the creation of a National Tip Safety Committee to provide guidance on best-practice for storage of waste materials at mines and quarries across the country.
Nine employees were singled out by the inquiry, with NCB chairman Lord Robens heavily criticised for failing to provide information on the organisation’s prior knowledge of the water springs located beneath the tip.
Despite responsibility being placed firmly on the coal board, neither the NCB nor any employees were prosecuted.