New chief executive Gerry Spindler said "geological problems" were behind the decision not to proceed with an expansion that would have opened up a second face in the Silkstone seam and help lift yearly output from 1.7 million tonnes to 2Mt.

Faults identified in the Silkstone seam, where workings are concentrated at a depth of over 2000ft, have put an end to the planned second face despite union pressure to work two coal faces to guarantee the mine’s future.

Spindler told the Yorkshire Evening Post the strategy to add additional people and, through changes in work rules and shift patterns, increase the output to more then two million tonnes a year was ill-timed and unfortunate.

“At worst it was simply wrong-minded,” he said.

"The challenge now is for everyone at Kellingley to engage in a meaningful process to explore all the feasible and viable alternative mining options that maximise output, for which we have a ready market and jobs,” he said.

Some 150 workers from the now-closed Selby mines were recently transferred to Kellingley but their futures now appear bleak. Six months ago an acrimonious industrial dispute over working hours at the pit was resolved when the Selby workers agreed to work permanent night shifts at Kellingley.

Meanwhile, Kellingley manager Adrian Carley is to join the company's so-called "swat squad", which aims to help collieries improve their performance.

He is to be replaced by Bill Tinsley, the former business manager at the Selby coalfield.