The author of a book investigating the Pike River tragedy says it's now blindingly obvious the mine was heading for a disaster.
Twenty nine men died after an explosion at the mine on 19 November, 2010.
Rebecca Macfie, the author of Tragedy at Pike River Mine: How and Why 29 Men Died, says the development of the mine was flawed from the beginning.
She says no one could see the number of holes and inflated risks in the Pike River project at the time, but in hindsight it was clear the mine had the potential for a disaster.
Ms Macfie says only light exploratory drilling was done before the mine opened and where there had been tests on gas content, the results were quite high.
She says the disaster happened because not enough research and information was gathered before the mine opened.
Ms Macfie also says it is astonishing there has never been an apology from the mine's board of directors to the families of the dead.
