Historical eventSeptember 152011

Gleision Colliery mining accident

Four miners are killed in the Gleision Colliery mining accident in the Swansea Valley, Wales.

Everything on September 15Original source

In context

When
Thursday, September 15 201115 years ago
Category
Historical eventA dated happening — a battle, treaty, launch, discovery, disaster or decision — recorded on this calendar day.
Era
21st century · 2010s
Recorded from
Wikipedia “On this day” feed

At a glance

Dates: From 2011-09-15.

Place: Cilybebyll, United Kingdom.

Type: mining accident.

What came beforeAI-assisted

Gleision Colliery was a drift mine (horizontal entrance) located at Cilybebyll in Neath Port Talbot, Wales. It was one of the few remaining deep coal mines operating in Wales at the time of the accident.

Catalyst / how it startedAI-assisted

On September 15, 2011, seven miners were working on a narrow coal seam when a blasting operation was conducted into a separate disused flooded mine network to improve air circulation. The blast breached the barrier between the active mine and the flooded adjacent workings, causing water to rapidly flood the tunnel where the miners were positioned.

Who was involvedAI-assisted

Seven miners were underground during the accident. Three escaped; one was rescued with life-threatening injuries; four remained trapped underground. The search and rescue operation involved emergency services and mining rescue teams.

TimelineAI-assisted

September 15, 2011: The blasting operation occurred and water flooded the tunnel, trapping four miners underground. Three miners escaped and one was rescued with serious injuries.

September 16, 2011: The four trapped miners were found deceased during the search and rescue operation.

What happened

Aftermath On 16 September the Secretary of State for Wales Cheryl Gillan announced that an inquiry would be held into events at Gleision Colliery and that lessons had to be learned. She said the investigation would initially be led by South Wales Police , then handed over to the Health and Safety Executive (HSE). The need for an investigation was echoed by First Minister of Wales Carwyn Jones and Labour Party leader Ed Miliband . [ 1 ]

The Gleision Colliery mining accident was a mining accident which occurred on 15 September 2011 at the Gleision Colliery, a drift mine at Cilybebyll in Neath Port Talbot, in Wales. The accident occurred while seven miners were working with explosives on a narrow coal seam. Following a blasting operation into a separate disused flooded mine network to increase air-circulation, the tunnel in which the miners were working began to fill with water. Three of the miners escaped,

September 15 through the years

Other entries on the same calendar day, in order.

  1. 1983Israel
  2. 1995Malaysia Airlines Flight 2133
  3. 2001Championship Auto Racing Teams
  4. 2004National Hockey League
  5. 2008Lehman Brothers
  6. 20082008 financial crisis
  7. 2011Gleision Colliery mining accident
  8. 2013Ivan Kulesh
  9. 2017Parsons Green train bombing
  10. 2020Bahrain–Israel normalization agreement
  11. 2020Abraham Accords

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Everything we record for 2011 →

Sources

Cite this page

“Gleision Colliery mining accident”, What's On This Date, https://whatsonthisdate.com/app/event/gleision-colliery-mining-accident-2011-september-15, accessed October 27, 2026.

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Questions about this entry

When did Gleision Colliery mining accident happen?

September 15 2011 — 15 years ago, on a Thursday.

Where does this text come from?

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