The coal deposits of the GHO are typical of those found within the Canadian Inner Foothills and Rocky Mountain areas, and have been subjected to a relatively high tectonic deformation. Exploration programs that use this setting are considered applicable to the Project area.

The GHO are located within the Elk Valley Coalfields. The coal measures are situated within the Upper Jurassic to Lower Cretaceous

Kootenay Group sediments. From earliest to latest, the Kootenay Group includes:
- Morrissey Formation: sandstones; subdivided into the Weary Ridge and Moose Mountain Members; 20–80 m in thickness;
- Mist Mountain Formation: interbedded sandstone, siltstone, mudstone, shale and thin to thick seams of bituminous to semi-anthracite coal; 450–550 m in thickness;
- Elk Formation: interbedded sandstone, siltstone, mudstone, shale and locally thick beds of chert-pebble conglomerate and thin seams of high volatile bituminous coal; 350–450 m in thickness.

The Mist Mountain Formation contains approximately 25 coal seams of potential economic interest, consisting of medium to high volatile bituminous coal.

Within the coal measures, there are three structurally-separated coalfields, the Elk Valley, Crowsnest, and Flathead coalfields. The Elk Valley coalfield is located within the Alexander Creek and Greenhills synclines, which are separated by a normal fault. The western edge of the Mist Mountain Formation, and therefore the dis ........

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.

GHO currently produces coal from two active pit phases (Cougar Phases 4 and 7) using open-pit coal mining methods, with primary waste stripping and coal mining completed by shovels and rear dump haul trucks. An additional three phases (Cougar Phases 8, and 9, and Swift (GHO)) are planned.

Geotechnical Considerations
The Cougar Phases 4–6 pit designs typically use bench heights of 15 m with a 65º face angle. The wall is typically double-benched, with 10 m wide safety benches, resulting in an overall wall angle of 51º. Where walls come into contact with rehandle, a 10 m berm is left, and the rehandle is sloped up at 37º. Spoils are built with a swell factor of 1.3, and inter-bench angles that vary from 20–37º, depending on configuration and reclamation requirements.

For the Cougar Phases 7–9 pit designs, the selected design shell was a 40º overall highwall angle, with a 65º inter-bench angle. The choice of angle was based upon the height of the highwall and geotechnical guidance for rock mass failures of highwalls at these heights.

Pit walls and spoils are monitored with a combination of prisms, GPS units, radar, wireline monitors, and piezometers. These systems are linked to near real time data collection and analysis software that ........

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