This will allow engineers the opportunity to deliver over-due maintenance (standard procedure is for this to occur every 25 hours of operation) to the Gorniczy Agregat Gasniczy (GAG) engine which has been operating continuously since installation was completed.

Miners placed a temporary seal on the Pike River portal after 29 miners perished in a series of mine explosions, the first of which occurred November 19, 2010. The GAG jet engine injects inert gas into the mine to extinguish the mine fire. A fourth, significant explosion occurred at Pike River November 28. No one was injured. This explosion follows a less violent third explosion November 26 and appears to have been stronger than the second explosion that occurred November 24.

Recovery operations at the mine, which located in a remote region near the town of Atarau on New Zealand’s South Island, continue under the control of the NZ Police working with industry experts and Pike River.

“Recovery of the 29 men lost in the Pike River mine remained the company’s top priority,” said John Dow, chairman, Pike River Coal. “The board, however, also had now to consider the company’s wider situation. It is imperative the company be able to assess the level of damage to the mine as soon as possible in order to reach meaningful conclusions about the options available to us.” This involves undertaking any repairs, replacements and rebuilding work and an assessment of the commercial feasibility of resuming operations.

Initial reports said shortly before the blast the mine lost power, which may have caused ventilation problems. That may have contributed to a buildup of gas underground. The mine accesses the coal seam, which lies at a depth of about 600 ft, through a 1.4-mile tunnel.