Better ore access
Phase 2 of Debswana’s Cut 8 Project is at an advanced stage, set for completion in 2016 as planned, bar unforeseen circumstances.
Debswana epitomises the thinking of an African country that does not take things – even its own relative wealth – for granted.
A few years ago, the company realised that the cost of accessing diamonds was becoming more expensive as its open pit mines got deeper. So, a feasibility study was undertaken through an element called strip ratio to establish whether Debswana should go underground to tap into the resource, or expand the existing pit at Jwaneng Mine. Strip ratio refers to the amount of ore and the cost of extracting it when compared to the amount of diamonds recovered from treating this ore. At Jwaneng, strip ratio and other results of the feasibility study justified the expansion of the pit instead of establishing underground mining activities. And this marked the beginning of the Cut 8 project, which is aimed at extending the life of the mine to 2028.
Launched in 2010, the Cut 8 project is now in Phase 2. Debswana Diamond Company hired Majwe Mining to provide contract mining services to mine over 156 million cubic metres (400 million tonnes) of material in a 66 month timeframe in order to provide access to the diamond bearing pipes underneath. Specifically, the contract involves maintaining, planning and scheduling of all equipment and ensuring that it is safely managed.
Explaining about Debswana’s objective in undertaking the project, Majwe Mining Project Director, Rod Fraser, says: “As pits continue to go deeper to access more diamonds, this drives the overall strip ratios up, which means the need for more cost effective solutions, efficiencies and productivities that large scale mining contractors can deliver are going to become more and more important.”
Overall, Cut 8 is a project of national significance and is critical to the Botswana economy. Understandably, there is urgency amongst contractors to deliver on time in order to ensure continuity of diamond bearing ore into the Jwaneng process plant, and consequently diamonds to help fuel economic growth.
Given the project’s magnitude, challenges are to be expected, acknowledges Fraser. He says the biggest challenge is boosting effective hours and dig rates. “We need to continue to strive to bring all of the systems (people, planning, power, water, maintenance) together in a fully integrated manner so that we can be more consistent with our production.”
Majwe Mining is a joint venture company involving Leighton (the world’s largest contract miner in prime locations across Australia, Asia, Middle East and Africa), Basil Read Mining and Bothagka Burrow Botswana (a local contract mining company).
A partnership between the Government of the Republic of Botswana and the De Beers Diamond Company, Debswana is one of the world’s largest diamond producers by value. It has mining operations at Jwaneng, Orapa, Letlhakane and Damtshaa in Botswana, and plays a fundamental role in the country’s economy, producing over 70% of the country’s export earnings and 30 per cent of its GDP.
Another project complementing Cut 8, the Modular Tailings Treatment Plant (MTTP) was commissioned last year, boosting Deswana’s plans to get the most of its diamond resources, according to the press release organisation mailed to African Mining Brief.
Mining treasure from trash
Once fully operational, the Jwaneng MTTP will be an additional revenue stream to Botswana
The primary objective of the MTTP Project was to design and purpose-build a modular treatment plant in order to mine and treat the Jwaneng Mine tailings treatment resource. The plant would be a stand-alone two million tons per annum modular tailings treatment facility. The Modular Tailings Treatment Plant (MTTP) is a very important project for the future of Debswana. The Jwaneng Tailings Mineral Resource (TMR) was chosen as an ideal site to construct this pilot facility given its high value product as well as relative availability of water and power. The project will create capacity and technical capability for Debswana to accelerate an additional revenue stream.
The Jwaneng Modular Tailings Treatment plant project was initially approved for full implementation by the Debswana Board in 2008. However, shortly thereafter it was put on hold due to the global financial crisis. Subsequently the Board approved P130m for early works and detailed design in September 2011 and the rest of the funding was then approved in May 2012 for full project execution. The MTTP is a first for Debswana, introducing and testing the modular concept in the family, with a possibility of adopting it at other operations. This pilot concept is one of the many steps in driving towards being a world-class high performance organisation
The execution of the MTTP was a hybrid arrangement with ADP Projects based in Cape Town as the Engineering and Design partners on the project with the Owners’ team playing the role of the Construction and Management, with support from the Engineering and Design team. This arrangement was also a first for Debswana and has facilitated skills transfer and invaluable experience to the Owners’ team in project execution. The MTTP project has jumped from milestone to milestone since construction began in 2012.
Construction projects are notorious for the difficulty involved in their execution. The management of safety, particularly in the construction of process plants, historically fell short of desired standards. However, the MTTP construction team and contractors demonstrated their capability and clear commitment to shaping the future of Debswana through the achievement of the one million Lost Time Injury Free man hours milestone February 2014.
The newly constructed plants has since been commissioned and is currently at the final stages of name-plate testing and hand-over as well as have delivered its first carats.