Underground mine cost control through proper mine drainage - Bogala mines

Abstract

A Bogala graphite mine is located in the Kegalle district, Sri Lanka. Bogala mines has been experiencing a considerable water inflow during the past many years, involving a significant cost on mine dewatering compared to other production costs. Daily mine dewatering data shows that the average volume of water to be pumped out from the mine is approximately 1.5 million gallons per day and, the cost incurred for mine dewatering is approximately Rs. 1.3 million a month. This research focuses on identifying the interconnection between the leakage points in two levels, with major water seepage takes place above 72 fathom levels and significant intrusion is at 52 fathoms level. Environmental isotope analysis were carried out in underground seepage locations to identify the exact locations where water recharging takes place inside the mine. Water samples were collected from leakage locations. They were analysed to measure the Oxygen-18 and Deuterium contents. The local meteoric water line was drawn with the help of rain water samples. The Oxygen-18 and Deuterium content was plotted in a graph in various suspected combinations. The clustered locations were analysed in a graph and tried to identify the interconnection between leakage points in two levels. Some possible interconnections were identified between 52 and 72 fathom levels.