Auckland, Mar 25, 2009 (ABN Newswire) - Restoration of Pike River Coal Limited's (NZE:PRC)(PINK:PKRRF) ventilation shaft, blocked by a rock fall in the lower 30 metre zone, is underway.
An experienced Australian 'Alimak' contractor has started work on driving a new shaft (called an 'Alimak raise'), to divert around the rock fall by intersecting the main shaft at about 50 metres above its base.
The Alimak process uses the drill-and-blast method to progressively construct a 2.5 metre shaft, with rockbolts and mesh used to support the new shaft walls as it is advanced upwards each day. This will prevent the sort of rock fall which occurred in the main shaft.
In preparation for the Alimak raise, a section of the existing tunnel floor has been excavated to 6 metres in height and more than 45 grouted cablebolts, 8 metres in length, have been installed in the roof to support the area of the new rise and to create the 'nest' for the Alimak equipment to park when explosives are deployed.
The Alimak equipment, already air freighted from Australia, is due for delivery to site by 27 March. Following installation of the equipment in the mine, the raise drill and blast will commence by mid-April and is due to be completed by end of May.
A nine man team will work in shifts around the clock to construct this new 'linking shaft'. The Alimak raise will be extended each day by using a working platform on a rail to carry tunnelling staff higher after each blast.
Meanwhile, drilling of a 'slimline' ventilation hole from the surface to pit bottom has commenced. This hole will then be reamed to 600mm diameter and fully cased with steel pipe to provide enough additional fresh air to allow one of the coal cutting machines, a continuous miner, to start producing coal during April.
Upon completion of the Alimak raise and the slimline hole, ventilation to the mine will be reestablished and the three coal cutting machines and in-seam drilling unit will be operating.
Pike River Coal Limited (NZE:PRC) is New Zealand's only listed coal mining company, becoming an NZX Top 50 company in July 2008. Pike River is owned by more than 8,000 shareholders and is in the business of mining and exporting premium hard coking coal.
Gordon Ward Chief Executive and Managing Director TEL: +64-4-494-0190
Brian Roulston Company Secretary TEL: +64-9-377-3517