The Rapid River Coal occurrence is located along Rapid River approximately 111 kilometres northeast of the community of Dease Lake.

The Rapid River showing is located within the Upper Cretaceous to Paleogene Sifton Formation, which consists broadly of poorly sorted, massively or crudely layered pebble to boulder conglomerate (Geological Survey of Canada Bulletin 376). The showing lies within 300 metres east of the mapped trace of the Kechika fault, a major, northwest-trending dextral strike slip fault that runs subparallel to the Northern Rocky Mountain Trench and is a component of the Tintina Fault zone (Geological Survey of Canada Bulletin 376).

Paleogene to Neogene sub-bituminous and lignitic coal has been recorded in the Rapid River valley, approximately 9.7 kilometres from its confluence with the Dease River. The coal seams are 15 to 30 centimetres thick. The contorted seams occur northeast of the Rapid River in a northwest-trending basin that measures 16 by 4.8 kilometres. The northern extension of the Upper Cretaceous to Neogene Sifton Formation hosts the coal-bearing sequence.