Pike River Coal Ltd did not have a proper understanding of the geology of its coal mine, a leading geologist told the Royal Commission into the Pike River tragedy today.
The commission is inquiring into the disaster at the West Coast coal mine, in which 29 men died last November.
Jane Newman, a geologist and director of Newman Energy Research with more than 31 years experience in the Pike River area, told the commission that after 2006 Pike River Coal Ltd employed overseas geologists.
They would not have had a proper knowledge of the unique and complex geology on the West Coast.
Her concerns led to her telling her husband, also a geologist, not to enter the mine in 2010.
"My feeling at that stage was that things were converging on a situation I wasn't happy about," Dr Newman said.
Independent technical reviews included in a Pike River Coal Ltd prospectus were written by people unfamiliar with West Coast geology, she said.
"They were written by people familiar with the coal mining geology in Australia."
Using a three dimension model of the coal seam she explained how drilling carried out by the company could have meant the company failed to uncover the presence of sandstone in the coal seam.
"In-seam drilling is not well designed for identifying this, especially if you are not aware of stratographic complexity, and I am not confident that the company was aware of this," she said.
She had provided Pike River Coal Ltd with informal assistance during the 2000s prior to 2009 but stopped because she felt as though she was "endorsing" an "inadequate approach" to the geology of the mine.
Former chief inspector of coal mines Robin Hughes and Harry Bell were expected to give evidence to the commission today, comparing the current mine inspectorate system with the system before 1992, when there was an independent mine inspectorate.
Ms Newman was giving evidence on the third day of the inquiry following the deaths of 29 men at the mine on November 19.
Mine safety changes needed now - Little
Earlier the former head of the Engineering, Printing and, Printing and Manufacturing Union (EPMU)said the Government could not afford to wait for the completion of the Royal Commission into the Pike River Coal mine disaster to make mine safety changes.
Andrew Little's warning came at the start of the third day of the inquiry in Greymouth into the series of explosions that ripped through the West Coast coal mine in November, killing 29 men working inside.
Mr Little, now the Labour candidate for New Plymouth, said the Government would be putting miners at risk if it did not make changes to the current mine safety regime.
He said the current mining inspectorate - which is part of the Department of Labour - did not have the expertise or resources to adequately cover the country's mines.
This was shown by the fact that only two of four ignition incidents at Solid Energy mines over the past eight weeks were investigated by mining inspectors.
"In any other country and certainly once upon a time in New Zealand there would have been [an inspection]."
It was not good enough to wait for the end of a commission to make changes.
"We need a dedicated mines inspectors with a chief mines inspector," he said.
Mr Little's comments come as two former chief inspector of coal mines Robin Hughes and Harry Bell are expected to give evidence to the commission today comparing the current mine inspectorate system with the system before 1992, when there was an independent mine inspectorate.
Yesterday Solid Energy chief executive Don Elder said the country could benefit from standardising mining practices as was seen in Australia.
"In Queensland there is a very large number of...standard operating practices, hundreds where the industry working with the regulatory bodies has said this is the standard way of doing things."
"Undoubtedly everybody benefits from that because you haven't got people reinventing the wheel so everybody is able to move forward faster."