Surface mining at Grande Cache Coal (GCC) is presently ongoing at the No. 8 Pit. In December 2009, the Energy Resources Conservation Board (ERCB) granted GCC a mine permit authorizing the development of a surface coal mine at the No. 8 Pit mining area. The surface coal mine operations employ conventional open-pit mining techniques using truck and shovel methods. Similar open-pit mining techniques would be employed at the future No. 12 Pit South A and No. 16 Pit. Overburden is drilled, blasted, loaded onto large trucks and hauled to waste rock dumps. Once the overburden is removed, run-of-mine coal is loaded onto trucks for transport to the coal processing plant. The coal is fed into rotary breakers that crush the coal into a predetermined size and remove oversized rock. The raw coal is then washed using a variety of techniques, dried and conveyed onto a saleable coal stockpile.
The geology in this area is typical of the Rocky Mountains with significant folding and thrust faulting creating structurally complex synclines and anticlines dipping at angles ranging from near 0 to approximately 80 degrees.