Northam Platinum Booysendal mine
The Booysendal UG2 North operating mine will soon reach its 160 000 ozpa target, but this is just the start for the greater Booysendal division.

Northam Platinum’s CEO Paul Dunne has revealed the company’s intentions to increase its annual PGM ounce volumes from about 400 000 oz currently to 1 Mozpa – by 2020. Th is target is well within reach thanks to its Booysendal division, which is already exploring massive organic growth opportunities while approaching steady-state production. This is in addition to the new ounces its Everest acquisition will put on the table. LAURA CORNISH visited the site and discovered what exciting opportunities lie ahead for the mine.

Situated on the southern end of the Bushveld Complex Eastern Limb, the Booysendal division PGM property is signifi cantly rich in PGM ounces, substantially more so than any of its neighbours with a 103.6 Moz resource (including the UG2 and Merensky reefs). “This equates to a lifespan of more than 50 years,” says Booysendal division general manager Willie Theron. By comparison, neighbouring mines Two Rivers and Mototolo have a 8.9 Moz and 7.5 Moz resource, respectively. The property has a 14.5 km strike length and dips about 11°. Booysendal’s fi rst operating mine – the UG2 North mine – celebrated production start-up in July 2013, which lifted Northam’s status from a single asset owner and operator. In October this year, the mine should reach steady-state production – 187 500 tpm/160 000 ozpa (4E PGMs) – which contract miner Murray & Roberts Cementation is comfortably on track with. It operates using a mechanised bord and pillar mining methodology. Underground workings are accessed by a cluster of four declines (three on-reef and one in the footwall), and accessed via a reverse decline system. “Because of our lower grades, we need high volumes. Zondereinde produces 300 000 ozpa at the same run of mine production rates,” Theron reveals.

Contract mining – Northam’s risk diversification strategy

South Africa’s platinum sector has been plagued with strikes. Northam has subsequently continued with its contract mining approach on the Eastern limb which it believes helps diversify such risks. Murray & Roberts Cementation, which moved onto the Booysendal property in 2010 when it was awarded the contract to develop the underground UG North mine, recently had its development/mining contract extended by a further three years. With vast experience gained on the property over the years, this action should ensure production targets are met. “Our contract mining adjudication process was based on certain criteria. Murray & Roberts Cementation was not necessarily the cheapest contractor, but it had and does still have vast experience in mechanised mining. This was critical in our decision-making process,” says Theron, whose vision for mining success lies with mechanisation. Theron says the two companies have established a joint relationship of openness and fairness. Braam Blom, project executive at Murray & Roberts Cementation, is particularly proud of the company’s project delivery at the Booysendal UG2 North mine to date. It is one of the company’s larger contracts and entails full management of the mine – including staff employment and training as well as machine operation and maintenance. It has also embraced its female population and brags two of the youngest, women section leaders underground. By year-end the company will oversee 1 500 workers: 1 200 of those will be direct employees of Murray & Roberts Cementation; the remainder subcontractors.

The company has achieved numerous milestone successes over the five year period and is comfortable and on track to reach steady-state production in October this year. “Our original contract and contract extensions have gone extremely well under (sometimes) very difficult conditions,” says Blom. “We are proud of our safety track record, which we attribute largely to the mechanised/trackless mining method, our pedestrian detection system and our commitment to constant safety awareness.” ‘Are you switched on?’ is a Murray & Roberts Cementation safety initiative which sees all workers, regardless of position, wear a whistle around their necks when they enter the gates. “Putting the whistle on puts us in the right safety frame of mind and enables us to alert our colleagues and coworkers to safety-compromising situations.” The development phase of the UG2 North mine has seen rates of about 500/550 mpm. “We are now transitioning from a phase of capital infrastructure to working infrastructure. Our last capital development will be in July 2015, after which the average rate drops to about 50 mpm. The bulk of growth will be on-reef after that and ensuring we make our monthly targets,” explains Ruaan Greef, Murray & Roberts Cementation senior engineer. The contract miner must manage a full 122 unit fl eet on site including LHDs, drill rigs, mechanised bolters, hybrid bolters, etc. supplied by Sandvik and Aard. Until recently, a surface workshop has provided all equipment maintenance needs. A new underground workshop was however recently commissioned and has enormous time and cost saving benefi ts. While the average grade is about 2.6 g/t, an increase in stoping, decrease in development and correctly cut package should see the grade settle at about 3 g/t. “Getting the correct ratios between waste and development is essential on site and between Northam and Murray & Roberts Cementation, we must ensure this is achieved,” Theron notes.

Mechanised approach a success

Unlike platinum mines on the Western Limb, which are focused primarily on the higher grade Merensky reef, Theron says the UG2 reef is the focus on the Eastern Limb, “and it lends itself to mechanised mining. The UG2 package is 180 cm (on average) whereas the Merensky package is about 80 cm.” Theron is a mechanisation fan, and believes that in addition to being inherently safe, it is the key to unlocking the property’s Merensky reef operation (alongside the infrastructure synergies). “Mechanised mining enables you to reduce labour, which compensates for high waste volumes, thereby enabling us to mine the narrow 80 cm Merensky reef economically. This is what our feasibility study is currently evaluating.” With a skills shortage in the area this approach in the longer term poses no threat to employment opportunities for the small communities inhabiting the surrounding area.

Organic growth – developing the Merensky North mine

“When we initially started at Booysendal, our primary objective was to deliver a 160 000 ozpa UG2 mining operation, and while we are approaching this, our objectives have evolved and our expectations have grown. We will soon target a monthly production rate of >200 000 tpm which would equate to just below 180 000 ozpa. But I believe the potential volumes from the UG2 and Merensky mines are closer to 250 000 ozpa within the next four to five years,” Theron reveals. Northam Platinum is current and underway with a feasibility study, as mentioned, to determine the viability of developing and mining Booysendal’s Merensky reef. Murray & Roberts Cementation has been contracted to mine a bulk sample as part of the study. “We are extremely positive that this is just the start of a new mine.” “Our intention is to start small – mining about 30 000 tpm and then building on this to around 70 000 tpm once we have the necessary infrastructure in place. This is however all pending a favourable outcome of the feasibility study, which is due for completion in Q4, 2015.” From a processing perspective, the nature of the Merensky reef is harder than the UG2 but this poses no challenge. “Our mills have been designed to handle hard material. We are reviewing the process plant as part of the feasibility study as well – and may require a slight increase in overall capacity”

Booysendal UG2 South mine (Everest South)

It is not difficult to understand Northam Platinum’s R450 million acquisition of Everest mine (on care and maintenance) from Aquarius Platinum South Africa (AQPSA). The ore body lies adjacent to Booysendal and its infrastructure (primarily concentrator and equipment) will allow Northam to ramp up production targets quickly. “As an operating asset it also provides synergies to exploit our larger Booysendal South and Central properties,” Theron points out. Everest has the potential (with a 230 000 – 250 000 tpm concentrator) to produce 250 000 ozpa of PGMS as well. This means that by 2020, the Booysendal mining division could be producing 500 000 ozpa. Following the Competition Commission’s approval, Northam will pay R400 million, which will place the full ownership of the property, infrastructure, equipment, plant, 30 MVA power supply, etc. in its hands. The final R50 million is payable on transfer of the mining right to Booysendal. “We are already assessing some of the equipment on site and hope within the next 18 months to be generating suffi cient tonnages to validate re-starting the plant including a chrome spiral circuit which operated for only a few months before it was shut down.” AQPSA had also progressed quite far with an opencast study on their mining property which Northam will continue evaluating as part of their organic growth strategies. While the Booysendal UG2 North mine is a great accomplishment for Northam and contractors such as Murray & Roberts Cementation, it is just the start of an operation capable of producing more than double its current production targets. MRA