Extraction Plan - Peabody Energy

Extraction Plan – North Wambo Underground Mine Longwalls 7 and 81.3.1 Mine PlanLongwalls 7 and 8 will be extracted using retreating longwall mining methods for secondary extractionof panels with a 262.8 m void width. Construction of development main headings and gateroads aremined using continuous miners.The Extraction Plan Application Area and proposed mine plan is shown in Figure 3 and keydimensions summarised in Table 2.Detailed mine layout drawings are provided in Appendix G (Coal Resource Recovery Plan), includingthe Approved Plan and Plans 1 to 6 required under the SMP Guideline. Appendix G also providesjustification of the mining layout, including a description of resource recovery and effects on futureresource recovery.Table 2Key Mining ParametersParameter Longwall 7 Longwall 8ROM Coal Extracted (Mt) 3.57 3.18Gate Road Width (m) 5.4Gate Road Height (m) 2.5 – 2.8Maingate (MG) Chain Pillar Width (m) 26.2 16.8 (for single abutment loading)26.2 (for double abutment loading) 1Tailgate (TG) Chain Pillar Width (m) 26.2Tailgate (TG) Chain Pillar Length (m) 94.6Longwall Void Width (m)(ribline of goaf edge)262.8Longwall Void Length (m) 3,294 2,908 2Extraction Height (m) 2.2 – 2.5Effective Extraction Height (m) 3 2.65Depth of Cover (m) 50 – 240ROM = run-of-mine.Mt = Million tonnes.1 A portion of the Longwall 8 maingate pillar will be designed for double abutment loading for a proposed adjacentlongwall (Longwall 9). Longwall 9 is subject to approval of a proposed modification to Development Consent(DA 305-7-2003) for additional longwalls at the North Wambo Underground Mine discussed in Section 1.1.2 Excludes the Wambo Homestead Exclusion Zone (WHEZ) as shown in Figures 2 and 3 and discussed inSection 1.6.1.3 Mining height is greater than seam thickness for the North Wambo Underground Mine longwalls due to mining dilutionresulting from mining conditions.Geology and StratigraphyThe Wambo Coal Mine is situated within the Hunter Coalfield subdivision of the Sydney Basin, whichforms the southern part of the Sydney-Gunnedah-Bowen Basin (WCPL, 2003). The coal bearing rocksof the Sydney Basin are Permian in age and are typically associated with low-lying gentle topography(WCPL, 2003). The overlying rocks of Triassic age cover large parts of the Sydney Basin and tend toform prominent escarpments where they outcrop (WCPL, 2003).EP/SMP LW7-8 Rev B December 2012 Page 10