Wambo Coal AEMR 2010-2011 - Peabody Energy

2010-2011 AEMR2.4.3 Underground OperationsWCPL’s North Wambo Underground (NWU) minesthe Wambo seam using continuous miners andlongwall mining methods. The first of eight longwallblocks (LW1) was completed in February 2009 andproduction commenced in the second longwall block(LW2) in March 2009. In December 2010, extractionof Longwall Panel 3 (LW3) was completed, withproduction of Longwall Panel 4 (LW4) commencingin January 2011. At the end of the reporting periodLW4 had retreated 1,950m. The completion of LW4is expected in October 2011. The Undergroundcontinues to operate seven days a week.In total 8 x 250m wide Longwall panels,approximately 3.8 km to 4 km in length will bedeveloped with the Longwall panels orientatedsouth-west to north-east. Longwall panels one tofive will be developed off main headings driven fromthe existing Bates North Open Cut highwall. Theremaining three panels will be developed by punchmining directly off the Homestead Pit Open Cuthighwall.WCPL primarily use Joy Mining Longwallequipment, including the Longwall operatingsystem. The Longwall panels are formed by drivingtwo sets of gateroads (the tailgate and maingateroads). Each gateroad requires two roadways(headings) to be driven parallel to each other (31 mapart). One of the roadways is used for personneland materials access and fresh air intake ventilationwhile the other is used for coal clearance and returnair ventilation. The roadways are developed usingtwo Joy 12CM30 continuous miners. Approximately10,349 m of roadway was developed in the 2010-2011 period with a total of 4,361 m of Longwallretreat.The headings are connected every 100 m by drivinga cut through from one heading to another. Thisforms pillars of coal along the length of thegateroad. The tailgate and maingate roads areseparated by the 250 m wide Longwall panel. Themaingate roads and tailgate roads are then linkedtogether by driving an installation road and bleederroad at the inbye end of the longwall panels.As the continuous miners develop the roadways,Run of Mine (ROM) coal is conveyed to a stockpilewith an approximate 70,000 tonne capacity. Whena sufficient stockpile is present, coal is loaded ontotrucks for transport to the CHPP. During the 2010-2011 reporting period, approximately 4.8 Mt of ROMcoal was produced.At the end of the reporting period the followingequipment was available for mining activities at theUnderground, including:2 x Joy 12CM29 Continuous miners;1 x Joy 12CM30 Continuous miner3 x electric shuttle cars with a 15 t payload;8 x Load Haul Dump (LHD) machines; 9 x personnel transporters SpecialisedMining Vehicles (SMV’s);Associated longwall equipment;146 Joy Roof Supports;2 x Joy 7LS2a Shearers;2 x BSL and AFC systems2 x Monorail system;2 x Pump sled; and2 x 5MVA TransformerThe old Wollemi Underground Mine was on careand maintenance throughout the reporting periodwith no coal being produced from this mine. The oldWollemi workshop, bathhouse and store facilitiespreviously used by the WCPL’s Undergroundoperations were decommissioned during October2008 due to the completion of the newadministration and bathhouse facilities. Planningwork was undertaken in this reporting period for thesealing of the Wollemi Mine and removal of the oldbuildings.2.4.4 Open Cut OperationsDowner EDI Mining are contracted to undertakeOpen Cut mining operations at WCPL. Open cutmining is divided into pits known as the Bates Pit,Bates South Pit, Montrose Pit and the HomesteadPit. The Bates Pit, Bates South Pit and theMontrose Pit are adjoining and linked via a miningcorridor. The Homestead Pit is a separate miningarea.Operations during the reporting period occurred inthe Bates Pit, Bates South Pit, the corridor ofMontrose Pit and the Homestead Pit. The currentOpen Cut workings are presented in Figure 2.2.Mining of the Open Cut commences with theremoval of vegetation and topsoil as described inSection 2.2. Following land preparation,excavators and trucks remove any weatheredmaterial as a “free dig” operation. The weatheredmaterial that can be free dug ranges from one metreto ten metres in thickness. The remainingoverburden is drilled, blasted and removed utilisingPage 22