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.
[1] The accident occurred in the Gleision Colliery drift mine in the valley of the River Tawe, north of Swansea, in Neath Port Talbot on 15 September 2011.
After an intentional explosion, a routine blasting operation to extract coal, at 09.21, the passage in which the miners were working rapidly filled with a large quantity of water.
[5] 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.
[7] On 18 October 2011, the mine manager, Malcolm Fyfield, was arrested but not charged by South Wales Police on suspicion of manslaughter by gross negligence.
[14] The poem "Gleision", a reflection of the accident, was composed by Welsh Poet Laureate Gwyneth Lewis who had visited the village only the previous day.