The Pre- Feasibility Study of Gold Mine Development, A Case Study of Sepon Deposit, Savannakhet Province, Lao PDR

Abstract

This study is about the pre-feasibility study of gold mine development in Lao PDR. The research area is located at Sepon Basin, Vilabouly District, Savannakhet Province. This research focuses mainly on technical development of open pit gold mine with three objectives. First, to construct the geological block model which provides the basis for resource/reserve estimation, and will be used as inputs in the stage of mine optimization, mine design and operation, Second, to develop a financial model using Discounted Cash Flow (DCF), and the criteria of Net present Value (NPV), the Internal Rate of Return (IRR), and the Weight Average Cost of Capital (WACC). Third, to address the environmental and social impacts from mine operation and proposed some mitigation guidelines. The geological model with 3,218 assays data collected from collected from 54 drillholes is prepared in MineSight input format. The geological volume extends 700 meters in x direction (Easting), 500 meters in y direction (Northing) and 250 meters in z direction (thickness).The results from resources estimation gives the geological resource of 34.87 million tonnes with the respective average ore grade at 0.58 ppm. The geological block model is constructed with the block dimension of 12.5m. x 12.5m. x 5m bringing to the total of 17,421 blocks. The ultimate pit is designed using Lerchs-Grossmann algorithm providing the mine mineable reserve at 2.44 million tonnes at the average grade of 1.53 ppm. This mine is schedule with 4 years of mine life at the average annual production capacity of 600,000 tonnes. For material handling, it requires five trucks, one wheel loader and one excavator to handle the production of 160 t/hr. In terms of financial estimations, the NPV is calculated at 1.93 million USD, and IRR of 22 percent that is higher than WACC of 12.6 percent. For the environmental mitigations, it is suggested to follow the Lao National Environmental Standard to control the noise, dust, vibration and some recommendation for blasting practice. In summary, this gold mine project is proven feasible taking into consideration of technical, financial and environmental issue.