Relatives of the four miners who died at the Gleision colliery near Pontardawe in 2011 have released a statement saying their loss will remain with them forever.
Video: Relatives of Gleision victims speak to ITV News
Former pit manager Malcolm Fyfield and owners MSN Mining were cleared of manslaughter charges this afternoon by a jury at Swansea Crown Court.
Mr Fyfield, 58, broke down in tears and hugged his wife Gillian after the not guilty verdict was delivered.
MNS Mining was also cleared of corporate manslaughter charges.
Video: Malcolm Fyfield and mine owners cleared of manslaughter charges
The charges were brought after Philip Hill, 44, Charles Breslin, 62, David Powell, 50 and 39-year-old Garry Jenkins drowned in September, 2011, when around 650,000 gallons of water were unleashed after explosives were used inside the mine.
Prosecutors said Mr Fyfield was negligent by allowing the men to dig towards an area where underground water was present.
But the father-of-two insisted he carried out safety inspections on the eve of the tragedy which showed no water was present.
Video: The scale of the rescue effort on 15th September 2011
The men had been working in a part of Gleision called H1 on September 15 when tragedy struck.
They were trying to break through an area called The Old Central Workings to improve ventilation.
Mr Fyfield, who was close to the blast site, managed to escape after crawling through dirt and sludge.
When he eventually reached the surface some 20 minutes later, he told rescuers: "There is no hope for the others".
Two other men who also managed to get out alive - Nigel Evans and David "Jake" Wyatt - later described the sound of the rushing water as like "jet engine" whoosh.
The prosecution said Mr Fyfield took staggering risks in allowing the work to go ahead.
Two witnesses for the Crown - outgoing mine manager Ray Thomas and Neath Port Talbot Council planning chief Alun Rees - both said they warned Mr Fyfield about underground water weeks before the massive flood.
But Mr Fyfield's QC Elwen Evans described the investigation into the tragedy as inadequate - saying many parts of the mine were not examined afterwards.
The defendant himself also said he had carried out three safety inspections the day before. He insisted he had examined both sides of the coalface and not found any water.
The prosecution said this did not happen as it would have been "impossible" to inspect the Old Central Workings because the area was covered in water.
However, expert witness and mine hydrology academic Dr Alan Cobb - who was called as part of MNS Mining's defence - said he believed it "was more likely than not" the water came from another part of the mine.
The jury took just under two hours to deliver the not guilty verdicts.
As well as tears of relief from Mr Fyfield, MNS directors Maria Nora Seage and brother Gerald Ward also both wept on hearing they had been cleared.
Trial judge Wyn Williams said: "This has been an extremely difficult case for all those concerned."
He paid tribute to the jurors and excused them from ever having to serve on a jury again.
Mr Fyfield declined to speak to journalists as he left the court with his wife and younger brother William, driving away in a white BMW.