In its March quarterly report released Thursday, the New South Wales producer said Newstan had continued to experience significant but intermittent difficulties with equipment reliability issues arising from damage caused to the old equipment.
As a result of these difficulties, in particular the impact of the ageing armoured face conveyor that is materially affecting the ability of the longwall to mine through the remainder of the current block (LW22), Centennial Coal has decided to relocate the longwall earlier than anticipated, at 7 cut-through.
During the relocation, the longwall will be thoroughly overhauled and a new and more powerful AFC installed. The overhaul will allow Newstan to recommence production in LW23 in late June 2006 and, according to the company, “return to profitability”.
“While the decision to relocate early will adversely affect the group’s 2006 financial year result, it will have a positive impact on 2007 financial year production and earnings,” Centennial said.
Work is also progressing on a permanent solution to resolve the unstable atmosphere around LW21, with fly ash being used to isolate and seal parts of the old goaf (voids) in the previous longwall extraction area.
Centennial said when completed, this should allow the current expensive campaign of inertisation to be terminated. As a precaution for the future, the group is looking to procure its own mobile inertisation plant, reducing its reliance on the more expensive large-scale unit being used at present.
Centennial did have one star performer during the quarter in its Angus Place operation. Production from the mine helped Centennial along to its quarterly ROM coal production of 4.2 million tonnes, and 12.5Mt year to date.
Angus Place achieved a record weekly production of 93,000t and its second-highest monthly production of 321,569t.
Tahmoor also set a new daily output record under Centennial’s management and subsequently a new mine weekly record of 88,500t in early April immediately following its “step-around” changeover.
The company said Springvale continued to perform well, recently completing its longwall changeover to the first of its 3.6km long blocks containing approximately 5Mt of coal. During the changeover, the opportunity was taken to upgrade the coal clearance system, longwall crusher and stage loader, thereby increasing the productive capability of the mine.
Mandalong produced 729,057t over the March quarter, impacted by a longwall changeover that commenced in mid-March.
During the quarter, Mandalong also completed the final commissioning of the 5.5km Delta coal clearance system. Together with its pre-existing Eraring system, Mandalong now has direct connections via underground and overland conveyors from the coal face to the two major Central Coast power stations.
Clarence achieved a small improvement in overall production rates with the commencement of extraction activities in its 330 panel, despite operating in variable conditions during the quarter.
Shift changes have been implemented at the mine and in the coming months, coinciding with the new enterprise agreement, mine management plans to implement changes to reduce operational complexity, improve maintenance planning and reduce pressure on infrastructure.
Of the group’s smaller mines, Awaba and Charbon continue to perform strongly. Myuna’s turnaround, following its transition from the Great Northern Seam to the Fassifern Seam, is gathering pace with mine production targets being regularly met or exceeded, Centennial said.
Mannering continues to make progress through the faulted area at pit-bottom, albeit slower than anticipated.
Meanwhile, Berrima encountered adverse geological conditions in the middle of the quarter, but has now returned to normal production levels.