Construction of a mining plant

The Mandiana mining company discovered a gold deposit with 700,000 ounces of reserves on a site east of the town of Kankan. To mine the deposit, there are plans to build a plant with a capacity of 2 million tonnes.

This investment will create 1,000 jobs in the construction phase and, once the construction of the plant is completed, which is expected to be in three years' time, 550 direct jobs.

The extremely remote location of the site involving numerous administrative formalities and construction site constraints is a difficulty that was identified in the project preparation phase and dealt with in the operations phase.

For example, the conditions of access to the zone to be studies: the samples have to be brought intact from the site to Conakry airport by track: 600 km covered in 18 hours.

Campaign of investigations

• 9 core-drilled boreholes Ø 101 mm 20 m deep, with the collection of intact samples, 3 boreholes equipped with piezometers
• 10 SPTs done at different points in each core-drilled borehole
• 73 excavator dug test pits 3 m deep with collection of remoulded samples placed in bags
• Laboratory tests on remoulded samples including 14 water content tests, 14 particle size analyses by sieving, 14 Atterberg limits tests and 9 Proctor tests
• Laboratory tests on intact samples including 5 CD triaxial tests and 5 permeability measurements in the laboratory
•  comprenant 5 essais triaxiaux CD et 5 mesures de la perméabilité en laboratoire

The boreholes were spread across an investigation zone measuring 2000 m x 2000 m including a 250 m x 350 m area for the operating zone (plant location).

In addition to these core-drilled geotechnical boreholes, Fondasol laid access tracks in a hilly relief to be able to carry out the  borehole drilling and collect samples with a mechanical excavator to define the borrow pits as part of the study on the re-use of the materials excavated on the site for the dyke.