Mine blast: Experts question build up - National - NZ Herald News

Are the safety lapses in the exploration and mining industry a worldwide phenomenon?

If they knew they were tunneling into the 60m wide zone of fractured rock (Hawera Fault zone), why did they not take extraordinary measures to channel the gas migrating through the fault away from the tunnel.

http://www.bbc.co.uk/news/world-asia-pacific-11805068

Again another case of willful negligence?

The natural hazards associated with coal mining include the build-up of methane and the risk of spontaneous combustion.

With an explosion inside a mine, transport, communication, ventilation and the means to monitor conditions inside the mine would be disrupted or lost, Mr Watson said.

The mine, which employs some 150 people, has been operational since 2008 and runs deep under the Paparoa Ranges on the rugged western coast of the South Island.

The missing include 24 New Zealanders, two Australians, two Britons and a South African national.

An electrician went into the mine at 1550 local time to investigate a power failure, and 1,500m (4,920ft) into the shaft he discovered the driver of a loader who had been blown off his machine. He then raised the alarm.

Mining experts said it could have been an explosion of methane gas, coal dust, or a combination of the two.