which company was involved in the coal mining in that place?
National Coal Board
Aberfan disaster
 The tip was the responsibility of the National Coal Board (NCB), and the subsequent inquiry placed the blame for the disaster on the organisation and nine named employees.

in which country/region did the aberfan disaster take place? Wales on what date did it take place? 21 October 1966 what happened in that disaster? A period of heavy rain led to a build-up of water within the tip which caused it to suddenly slide downhill. what things came sliding down? A colliery spoil tip. were there any deaths caused due to this slide? Yes, death of 116 children and 28 adults.
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Aberfan disaster [SEP] Introduction
An official inquiry was chaired by Lord Justice Edmund Davies. The report placed the blame squarely on the NCB. The organisation's chairman, Lord Robens, was criticised for making misleading statements and for not providing clarity as to the NCB's knowledge of the presence of water springs on the hillside. Neither the NCB nor any of its employees were prosecuted and the organisation was not fined.