Lucara Diamond Corp has provided an update on the ongoing Feasibility Study for a potential underground operation at the company’s 100% owned and operated Karowe Diamond Mine located in the Republic of Botswana. In 2018, following the release of a positive Preliminary Economic Assessment, the company embarked on a $29 million technical program to support a Feasibility Level study for a potential underground operation at the Karowe Diamond Mine, with the aim of extending mine-life from 2026 to at least 2036.
This program included a mineral resource update, geotechnical drilling of the country rock and AK06 kimberlite, hydrogeological drilling and modelling, and mining trade off studies to address risks and issues identified during the PEA. A total of $23 million was spent out of a 2018 budget of $29 million in support of this work and resulted in significant de-risking of the key technical components associated with the potential underground development.
Mining method selection is being considered in accordance with the geotechnical and hydrogeological interpretations and technical data already collected and in progress. At present four possible alternatives are being studied. These include variants on block cave with shaft access, sub-level retreat/sub-level cave with access via a decline, and conventional vertical crater retreat stoping followed by block cave via shaft access. As greater clarity on the rock mass and geotechnical characteristics of the host rocks and units internal to the South Lobe become available a final decision will be made for the most appropriate mining method.
Lucara continues to engage in discussions with the Government of Botswana to extend the mining lease to include underground mining operations. In support of these discussions Lucara is updating the Mine Closure Plan, closure cost estimates, the Environmental Management Plan, as well as the Social Economic Impact Assessment.
Lucara’s Board of Directors have approved a budget of $14.8 million to complete the technical program and the FS study in 2019. Drilling is expected to be completed toward the end of Q1 2019 with logging, data collection, and the receipt of laboratory results expected toward mid Q2 2019. Completion of the FS study and final reporting is expected in late H2 2019.