The Kenmare mine of QCT Resources in Queensland's Bowen Basin continues to struggle with difficult conditions in the Lower Seam where mining began in August last year. Weak ground in the gateroads is necessitating the installation of secondary support such as tendons. Narrow chain pillars are thought to be the cause of the support problems in the gateroad.
Stress transfer from the Upper Seam is also generating a stress concentration in the middle of the face exacerbated recently when the longwall encountered a cavity. The roof subsequently collapsed from chock 50 to the tailgate.
The mine is believed to have elected to pull the face up short 250m from take-off, some 4-5 weeks ahead of the scheduled changeout in May. The cavity is being filled with PUR prior to bolt up. Recovery of the chocks means the roof will have to be reformed with steel and grout.
QCT has also announced its results for the quarter ended 31 March. During the period 3.7 Mt were shipped, comprising 2.776 Mt from its share of the Central Queensland Coal Associates (CQCA) and Gregory joint venture mines and 1Mt tonnes from the South Blackwater mines.
Shipments from 100% owned South Blackwater reflect reduced production at the Kenmare underground mine, QCT said, as mining proceeded through a large fault zone early in the quarter.
"The longwall equipment is being relocated to the next mining panel in April/May. Shipments in the fourth quarter are likely to approximate shipments in the third quarter."
