Design of Flood Drainage in Golgohar Iron Ore Mine#3

The iron ore minerals reservoir of Golgohar Mine#3 is more than 660 million tons. It is the biggest in Iran and rate of ore extraction is more than 15 million tons per year. The pit takes place on the way of runoff pathway of this watershed and it needs an especial strategy for conserving the pit mine during next imminent floods. The area of Mine# 3 watershed is 20785700 square meters and its general slope in its topography map is 0.59 percent; then initial scheming indicates it can causes a great deal of problems for mining operation n the next floods; particularly, the pit is located into degree 4th sub branch of a main ephemeral river. For this purpose, the Soil Conservation Service Curve Number (SCS) method was employed to estimate intervals period of next floods based on the magnitude, the intensity and the duration of precipitation events data. Conceptual design of runoff drainage of the watershed was designed to lead the flood to a better pathway location. The Mine#3 overburden deposition occupies a huge area on the watershed; and it has been considered and redesigned in terms of size, form, dimensions and location to manage as a physical obstacle against next floods. Hydraulic calculations were applied for designing two essential open channels which can preserve the pit.