The chrome mine in Katjel is a small mine opened with a vertical shaft sinking from a horizontal mining work (adit). The orientation survey of the different levels of this mine is carried out with shaft plumbing method, a process of transferring bearing (two points) from surface to the mining levels opened from the shaft. The most dangerous factors causing errors in the mechanical plumbing correlation method in this mine are non-large diameter of the vertical shaft, the deflection of wires by air current of the ventilation system, the presence of water dropping down along the shafts trunk and the geometry of shaft inset. The factors mentioned above present in this mine, have led to an orientation error correlation of surface and underground survey, greater than allowed error. In this article we are briefly introducing the methodology of the mining measurements for the orientation of mining works in this mine, the errors found in the position in the plan and height of the mining works, the factors that caused these errors and the control possibilities to avoid such mistakes.
