The mining operations use conventional truck-and-shovel methods. As a result of delivery requirements and varying coal seam qualities it is necessary to have multiple coal seams exposed at any time.
FRO currently produces coal from six active pit phases (Swift 1A, Swift Lake Mountain, Swift 2N, Swift 2S, Eagle Pushback, Eagle West 2) using open-pit coal mining methods, with primary waste stripping and coal mining completed by shovels and rear dump haul trucks. An additional 25 phases (four in Swift pit, four in Eagle pit, 16 in Castle and one in Turnbull West) are planned.
The following design criteria is generalized, each area has been assessed geotechnically and has specific set of standards that are followed based on multiple factors including bedding angle, rock type and faulting:
• The Eagle pit designs typically use bench heights of 15 m with a 65º face angle. The wall in Eagle is typically double-benched, with 11.5 m wide safety benches, resulting in an overall wall angle of 49.6º;
• The Swift pit designs typically use bench heights of 15 m with a 65º face angle except for Swift Lake Mountain, which uses same bench heights but with a 70º face angle due to the rock characteristics in that area. In the Swift Phases the wall is double-benched, with 10 m safety benches, resulting in an overall wall angle of 51º. In Swift Lake Mountain the walls are single benched with 12.5 m safety benches and an overall wall angle of 40º;
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