The coal deposits of GHO are typical of those for Inner Foothills and Rocky Mountain areas which have been subjected to a relatively high tectonic deformation. Coal deposits of this type are characterized by tight folds, some with steeply inclined or overturned limbs. Fault offsets are common but fault-bounded plates generally retain normal stratigraphic thicknesses. These characteristics suggest that the GHO coal deposits should be categorized as “Complex”, in accordance with the Geology Type descriptions given in GSC Paper 88-21. The Deposit Type is classified as a Surface Mining type.

The coal measures of GHO are contained in the Mist Mountain Formation of the Upper Jurassic to Lower Cretaceous Age, Kootenay Group of sediments, deposited approximately 120 to 150 million years ago. Interbedded sandstone, siltstone, mudstone and coal seams were deposited throughout this period. The Mist Mountain Formation is approximately 500 m to 600 m thick. Subsequent to deposition, the sediments were impacted by the mountain building movements of the late Cretaceous to early Tertiary, Laramide Orogeny, which produced the structural features that now dominate the area. The Elk Valley Coal Field, including GHO coal measures, is structurally contained within the Lewis Thrust Sheet, bounded to the west and east by the Bourgeau and Lewis Thrust Faults, respectively.

North-south trending thrust faults associated with the tectonic movements have resulted in repeating of all or parts of the coal sequence including whole blocks of the coal-bearing Mist Mountain Formation. Subsequent northerly trending normal faults have also displaced and further divided the sequence. From an economic point of view, the Mist Mountain Formation is the most important formation of the Kootenay Group. The formation contains coal seams that measure up to 18 m in thickness. Generally the coal rank varies from low volatile bituminous in the lower part of the formation to medium and high volatile bituminous in the upper part of the formation.

The major structural features of the Elk Valley Coalfield are two, north-south trending, asymmetric synclines with near horizontal to steep dipping thrust faults, and a few high angle normal faults. The Greenhills Syncline is located to the west of the Fording River with the Alexander Creek Syncline lying to the east. These synclines are separated by the regional Erickson Normal Fault located along the eastern flank of the Burnt Ridge-Greenhills Range complex that lies west of the Fording River. The Greenhills Fault, a normal fault related to but of lesser displacement than the Erickson, separates the main Greenhills Range coal block, dropped down to the west, from the Burnt Ridge coal block to the east. The Crow Ridge coal is contained in the western side of Burnt Ridge.

The Alexander Creek Syncline can be traced from the southern property boundary of the Line Creek Mine to the northern end of Weary Ridge, north of the Fording River mine site. The Ewin Creek property, lies between these two points and is contained mostly on Imperial Ridge. This property is situated in the east limb of the syncline and is part of the GHO mine site coal resources. The coal measures here dip west towards the Fording River valley. More exploration work is required to better understand the geology.

This episode of thrust faulting explained above was likely contemporaneous with the later stages of mountain building.

The intervening anticline that had developed between the aforementioned two major synclines, was subsequently faulted by the Erickson Fault, and then eroded by the existing Fording River.

Mineralization
The coal bearing section of the Mist Mountain formation is shown in Figure 10. The Mist Mountain Formation is approximately 500 m thick with the depth of burial ranging from surface exposures to greater than 1,500 m. The coal measures on the GHO property contain bituminous grade coal seams with varying volatile matter contents. The Mist Mountain Formation contains approximately 25 coal seams of economic interest, consisting of medium to high volatile bituminous coal.

The quality of the coal in the Mist Mountain Formation seams varies with depth of burial and location along the strike of the deposit. With standard coal washing processes to remove impurities, these seams will provide coking coal suitable for use in steel-making. Most coal products produced by GHO require a blend of coal mined from two or more seams, and possibly coal from different mining areas.

GHO uses the following categories to identify the different types of coal mined from the pits.
* Standard Coal: < 24.5% Volatile Matter (VM) includes lower seams.
* Premium Coals: 26.5% to 28.5% VM includes all seams.
* Eagle Coals2: > 28.5% VM includes upper seams.
There are seams with Volatile Matter content near 25%, which GHO blends into both Standard and Premium categories.

GHO currently produces coal from three active pit phases using open-pit coal mining methods, with primary waste stripping and coal mining completed by shovels and rear dump haul trucks. The three active pit areas at GHO are the Cougar Pit Phases 4, 5 and 6. Future developments are planned for Cougar Phases 7-11.

Electric cable-shovels are utilized to load overburden and interburden waste into a mixed fleet of 290 and 218 tonne capacity end dump trucks, exposing the steeply dipping coal seams in a series of benches. Before loading, the waste is subject to drilling and blasting, which fragments the rock so that it can be dug by the shovels. Mine waste is backfilled into the advancing mining pit whenever practical and to external spoils as required. The coal is loaded by front-end loaders, which receive assistance from bulldozers that push the coal into piles on the bench. The coal is delivered to a stockpile by the breaker by large haul trucks, where it is fed to a breaker then transported by conveyor to the processing plant. The completed pits and waste dumps are reclaimed in a manner that fulfills requirements set out by law in the Province of British Columbia.

The GHO 2015 Life of Mine Plan (LOM) has a mine life of over 40 years, and will produce 209.3 mTCC for sale at a clean strip ratio of 11.6:1 bcm/tonne. Cougar Phases 4, 5, 6 are Proven and Probable Reserves while Cougar Phases 7 - 11 are entirely Probable Reserves. Figure 15 to Figure 19 outlines most of the LOM Mining Sequence.

Medium and long term exploration will continue to focus on the Cougar Phase 7-11, to improve seam definition and coal quality predictions well in advance of mining.

The 2015 LOM production rate is 5.2 to 5.3 mTCC through to 2024; with a production rate of 5.0 to 5.5 mTCC through to the end of reserves.

The current mining fleet is comprised of the following equipment with number of units in parenthesis:
• P&H 4100XPB electric cable shovel (1)
• P&H 4100XPC electric cable shovels (2)
• P&H 2800XPB electric cable shovel (1)
• LeTourneau L1850 front end loaders (1)
• Caterpillar 994 front end loaders (2)
• Komatsu WA 1200-3 front end loader (1)
• Bucyrus Erie 49R production drills (3)
• Caterpillar MD6640 production drill (1)
• Haulpak 830E waste/coal rear dump haul truck(8)
• Haulpak 930E rear dump haul truck (29)
• Bulldozers (10)
• Graders (5)
• Backhoes (3)
• Scrapers (1)
• Water trucks (1)

The basic operation of a coal processing plant is separation by gravity. Based on the difference in specific gravity of coal and rock, the coal can be separated to a desired specification. To assist gravity separation, mechanical means are also used.

At GHO, this is accomplished through vibrating screens, cyclones, spirals, and flotation cells. Each technique contributes to the recovery of clean coal from the raw coal feed.

Breaker
Coal is fed to the breaker where rock that is greater than 2” is separated from the coal and any coal that is greater than 2” in size is broken and passed through perforated breaker plates. This is then fed to the raw coal silos. Rejects from the breaker are piled and hauled away using loaders and trucks supplied by the Operations Department.

Wash Plant
GHO has two raw coal silos which can hold up to 1,800 tonnes each. The silos are used to store the raw coal before it is processed in the plant.

Deslime screens are large vibrating screens used to split the coal feed into different sizes. Material larger than 1.0 mm reports to the Coarse Circuit. Material smaller than 1.0 mm reports to the fines circuit.

Heavy media cyclones are used to separate coarse rock from coarse coal. Coarse coal goes out the top, while coarse rock goes out of the underflow. Vibrating screens used for cleaning and dewatering and excitors are used to “throw” the material across the deck.

Magnetite is used to control fluid density. Magnetite has a solid density of 5.1 but the process dilutes it with water to an SG range of 1.40 to 1.54. The higher density water/magnetite slurry helps more material “float”, meaning more ash (more rock), but also more coal, will be recovered in the product. Magnetite is expensive, so it is recovered through washing at the Reject and Clean Coal Screens and then passed over magnetic separators.

Flotation cells are used to separate the fine coal. Fine material from the cyclones is sent to the first stage or rougher flotation cells. Kerosene and methyl isobutyl cabinol (MIBC) are used to form bubbles when agitated, and the coal sticks to the bubbles and floats to the top. The rock sinks and goes out the underflow. The resulting concentrate goes to the clean coal thickener, and underflow goes to the scavenger flotation cells.

The scavenger cells are used as a second chance to float any coal that may have not floated in the rougher. Again the concentrate goes to clean coal thickener, and underflow goes to the refuse thickener. The thickeners rakes move thickened material to the Disc Filters which use vacuum pressure to extract the water out of the coal, making a filter cake.

Dryer
Discharge from Disk Filters (filter cake), fine coal centrifuges and Basket Centrifuges are combined to feed the dryer. The dryer is fueled with natural gas or thermal coal which is burned and the heat produced evaporates the moisture from the coal. The dryer takes coal from the plant at about 16% moisture and dries it to about 8% moisture.