Sundance Resources started topographical survey on Mbalam-Kribi rail route, page-8

Thanks Westcott that does seem to make sense now. If it is 200m tonnes a year then they will definitely need a double track all the way. Worlds best practice at present is about 30,000 tonnes per train. So that works out at about 6800 trains a year or about 13,600 trains including empty running back to mine or about a train every 40 minutes. There is no way you would be putting 30,ooo tonne trains into passing loops every 40 minutes so for that volume it would have to be double track. Simply not practical otherwise. Of course they may start out with much lower volume on a single track with passing loops and then as the cash comes in build a double track to up the volume. Either way you are correct...they need to set aside the corridor for an eventual double track.