The manager of the Gleision mine has appeared at Cardiff Magistrates Court to face gross negligence charges.
Four men died when the mine, near Pontardawe, flooded in 2011.
Mine manager, Malcolm Fyfield, has been charged with four counts of gross negligence manslaughter.
Malcolm Fyfield spoke to confirm his name, address and date of birth. He was bailed to appear at Swansea Crown Court on February 11th.
MNS Mining Limited, which owned the mine, also faces four charges of corporate manslaughter.
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