Inside Mining May 2013

www.miningne.ws

HOT SEAT

THE KNOWLEDGE YOU NEED

Golder Associates’

Francois Marais and Charles Naidoo on the challenges, emerging trends and best practice applications for tailings P8

Highly commended 2012 PICA Cover of the Year - B2B Publishing

ining

MEDIA

FROM THE INDUSTRY EXPERTS

NuWater

Challenge us to

clean your water

DIAMONDS & GEMS

Celebrating rare and unique discoveries

UNDERGROUND MINING

Changing perceptions and reality

SPECIAL FEATURE WATER: the issues,

the challenges and the solutions P37 ISSN 1999-8872 • R40.00 (incl. VAT) • Vol. 6 • No. 5 • May 2013

CONTENTS

T H E K N O W L E D G E YO U N E E D

ining

May 2013

FROM THE INDUSTRY EXPERTS

ON THE COVER

Highly commended 2012 PICA Cover of the Year - B2B Publishing

www.miningne.ws

MEDIA

14

HOT SEAT

THE KNOWLEDGE YOU NEED

Golder Associates’ Francois Marais and Charles Naidoo on the challenges, emerging trends and best practice applications for tailings P8

LQLQJ NuW Nu Wa ate ter ter

clean your water

DIAMONDS & GEMS UNDERGROUND MINING Changing perceptions and reality

SPECIAL FEATURE S WATER: the issues, the challenges and the solutions P37 ISSN 1999-8872 • R40.00 (incl. VAT) • Vol. 6 • No. 5 • May 2013

18

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P4

Challenge us to

Celebrating rare and unique discoveries

3

NuWater: Challenge us to clean your mine water

FROM THE INDUSTRY EXPERTS

Whether the challenge is too little or too much water, the requirements for flexible, effective and efficient treatment and desalination solutions suited to the specific demands of the sector continue to grow. NuWater has the answers.

EDITOR’S COMMENT A sparkling issue

HOT SEAT Tackling tailings – Golder Associates tackles Africa

HOT TOPIC

12 WorleyParsons and TWP take the first step DIAMONDS & GEMS

14 Karowe – a truly rare and spectacular find 18 Letšeng’s big expansion on a minimal budget 22 Lace – DiamondCorp’s leading lady 26 Another gem from Cullinan 26 De Beers’ ancestral heart 27 Rockwell Diamonds kisses Klipdam goodbye 30 Crystal-like andalusite 34 Diamond process professionals

52

WATER WATCH

38 Central Basin’s AMD treatment plant takes shape 44 Technical paper: Pollution remediation with nanoscale materials

48 Salty solutions sink in for process water recycling 50 AMD tailings retreatment 52 Anglo ladies lead the water way 54 MC Process takes dissolved air flotation a step further

57 The beginning and end of water preservation 58 Top treatment for mine camp wastewater 62 Gas detection – a water awakening UNDERGROUND MINING

74

70 Redpath Mining SA – shaft sinkers, not 73 74 76

contract miners 20 side-discharge hopper wagons en route to Rustenburg Platinum Mines A shameful reality for women underground Underwater mining: Marine miner trawls for more carats

MINING SERVICES

78 Software standardisation 80 Enterprise development clean-up Inside Mining 05/2013

1

 Editor's comment Publisher Elizabeth Shorten Editor Laura Cornish

A SPARKLING ISSUE

Journalist Reggie Sikhakhane Head of design Frédérick Danton Senior designer Hayley Mendelow Designer Kirsty Galloway Chief sub-editor Claire Nozaïc

Hot topic knockout

Sub-editor Patience Gumbo Marketing & online manager Martin Hiller

I’ve been trying desperately to find the right words to portray my experiences in putting

Production manager Antois-Leigh Botma

this issue together, and I’m coming up with too many to fit into a single page! So let me put it simply: it has been amazing, for a number of reasons, and I will tell you why…

Diamonds – need I say more? Any woman who says she doesn’t like diamonds is lying. For me, writing about diamonds is only one facet to my love for the stone.

Seeing them? Of course – they are truly one of the most beautiful things on earth. But my true appreciation for the diamond goes much deeper. Diamond formation is a truly spectacular thing – the right temperature (extreme heat), the right pressure (extreme pressure) and the right timing are all critical factors that need to be perfectly aligned in order to create a diamond. I only learnt in the past month that if a diamond, once formed, does not reach a ‘mineable’ level in time, it will likely resorb back into the earth. Fascinating! How many great diamonds have been missed as a result?

The combination of these factors is definitely the reason for the stone’s rarity. And with every passing year, supply is becoming more constrained as demand escalates. I wonder if there will be any real diamonds left for our grandchildren’s children? Experts are already predicting that demand will noticeably exceed supply from 2015.

Anyway, I’m getting sidetracked. Why is this issue in particular so amazing? It’s thanks to good luck and good timing. Petra Diamonds revealed the discovery of a particularly magnificent blue diamond. Lucara Diamonds has not only recovered a large 239 carat stone, but is uncovering numerous rare sky blue diamonds. Gem Diamonds is in the middle of investigating international technologies to ensure its sacred, large diamonds don’t run the risk of getting crushed. See what I mean? Could our diamond feature have been timed any better?

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The Wits Basin AMD situation is really bad, probably worse than we think

On-site at the TCTA Germiston AMD project – I’m sure I’m one of the first journalists to see the project in action

Annual subscription:

South Africa: R420.00 (incl VAT & postage) African countries: US$80 Foreign: US$100 E-mail: subs@3smedia.co.za ISSN 1999-8872 Inside Mining Copyright 2013. All rights reserved. ___________________________________ All material in Inside Mining is copyright protected and may not be reproduced either in whole or in part without the prior written permission of the publisher. The views of contributors do not necessarily reflect those of the publishers.

Diamonds aside, our first water-branded issue is sure to be a hit! It is, without a doubt, the biggest section in the magazine and the reason for this is obvious: water is a hot mining topic. The need to preserve, clean and respect it is more important now than ever before. Everyone is looking to make a positive impact on the environment – and I mean everyone!

I was fortunate enough to visit the first new acid mine drainage treatment plant, situated in Germiston – right under our noses. Its location and the reality of its existence hit me hard.

The Wits Basin AMD situation is really bad, probably worse than we think – delays are non-negotiable. Being on-site, talking to TCTA and the contractors involved, I have tried to cover all angles of this project, so be sure to read how the project has evolved, its progress and the long-term future planning as well.

You will find it on page 38.

The rest of the feature is filled with challenges, emerging issues and a variety of solutions to the water crisis. The water wheel is turning and progressive developments are happening.

I love it!

To our avid readers, be sure to sign up

and get the latest updates and inside scoop from the mining industry. Check out what we are talking about on our website, Facebook page or follow me on Twitter and have your say. @mining_news www.facebook.com/pages/Mining-News

Inside Mining 05/2013

3

 Cover story

NUWATER

Challenge us to clean your

Water is a hot topic in the mining sector as social responsibility expectations and more stringent environmental regulations enforcement rise. Whether the challenge is too little or too much water; the requirements for flexible, effective and efficient treatment and desalination solutions suited to the specific demands of the sector continue to grow.

I

t is becoming abundantly clear that the conventional approach to water and wastewater infrastructure does not meet the specific and onerous demands of the mining sector. In order to meet water treatment challenges, the same ingenuity that has been applied to mining extraction and processing techniques needs to be applied to mine water management and treatment.

Recognising this, NuWater was built from the ground up specifically to address the unique water and wastewater treatment and reuse requirements of the mining, and oil and gas sectors. “Since the company was established in 2010, we have gone about building an expert engineering team and

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Inside Mining 05/2013

technology portfolio that allows us to offer some of the most innovative water and wastewater treatment solutions and services available to these sectors,” says CEO John Holmes.

“In particular, we have focused on agility and flexibility, both in terms of our technology and plant designs, as well as our commercial offerings. We also recognised early that having the best available product is only part of what our clients demand. As a result we have instilled an obsessive customer-service culture throughout the organisation, underpinned by honesty and respect.”

In a short space of time, NuWater has proven the effectiveness and efficiency of its

large-scale, completely ‘modular & mobile’ water treatment and desalination plants, and demonstrated the benefits of rapid plant deployment and, where necessary, redeployment. The responsiveness and flexibility that its plants offer is starting to reset expectations in the mining sector. “We have also had the opportunity to demonstrate and prove our commercial flexibility on a range of projects, with commercial models ranging from full service build, own and operate (BOO) through to plant rental and more conventional equipment sales,” Holmes continues.

In all cases, NuWater retains complete responsibility for design, manufacture and installation, as well as a very high level of

 Cover story

mine water

ongoing involvement in the operations and maintenance of these plants, including 24hour remote plant monitoring from its operations centre in Cape Town.

From a technology perspective, NuWater – and its predecessor company, GrahamTek – has long been recognised internationally as having some of the most advanced reverse osmosis (RO) technology available. RO is the default choice for large-scale desalination applications, be it seawater, brackish water or wastewater desalination. NuWater’s patented large-diameter 16-inch RO technology, originally invented in South Africa, was pioneered in 2007 at the Singapore Public Utilities Board’s 55 000 m³/d secondary wastewater reclamation plant, the Bedok NEWater factory.

The high quality of the water produced from the Bedok plant results in most of it being directed for use in electronic wafer factories, with the balance being recycled for indirect potable reuse. The factory produces about 5% of Singapore’s water requirement

and is also home to the country’s NEWater visitor’s centre, which explains to visitors the technology used to reclaim clean water from wastewater. In 2007, NuWater also commissioned the world’s first 16-inch RO seawater desalination plant for YTL PowerSeraya's power station on Jurong Island, Singapore.

Global Water Intelligence voted this plant ‘Desalination Plant of the Year, 2008’.

Aside from the superior performance and efficiency of NuWater’s 16-inch RO technology, another key feature is that the technology is significantly more compact than conventional 8-inch RO technology. This is critical to achieving true plant modularity and mobility, which in turn allows for rapid deployment and, where necessary, redeployment of large-scale capacity for mine wastewater treatment and reclamation applications.

“Having proven that our 16-inch RO technology and proprietary plant design allows for a completely ‘modular & mobile’ large-scale RO solution, we then successfully set about designing the most compact

high-capacity ultrafiltration (UF) pretreatment modules. We have also extended our high capacity UF and RO ‘modular & mobile’ product portfolio further to cover brine treatment and expect to deploy the first commercial modules in the next few months.

Our product development team is also working on an RO pretreatment module based on ceramic membranes for release in the next few months,” Holmes reveals.

This ceramic membrane technology is more cost-effective than equivalent polymeric membrane solutions and has the added benefit of being resistant to acidic water or any other chemical damage. “We expect this treatment module to be particularly useful for mining applications.”

“Superior technology is all well and good, but at NuWater we appreciate that real knowledge and capability is only built through experience, often gained through sweat and tears. Nowhere is this more true than in the mining sector where operating conditions are challenging and mistakes and

Inside Mining 05/2013

5

 Cover story

WATER REGENERATION & DESALINATION

Seawater

Surface Water

PRIMARY WATER TREATMENT

OPTIONAL WASTE TREATMENT

Brine / Waste Stream

Effluent From Other Sources

Groundwater

Using proprietary technologies, NuWater provides a range of products, services and financing solutions to treat or reclaim almost any quality and quantity of water.

Our modular and, where relevant, mobile treatment plants allow for rapid deployment or redeployment, making them suited to decentralised water treatment applications (including specialist applications such as mining and oil & gas). Wherever possible, NuWater also aims to extract value from the waste streams created.

Wastewater

People

Clean Water

Mining Industry

Oil & Gas

Inorganic Salts

Organic / Biomass

Recycle

Fuel

Disposal By-Products

Challenge us to clean your water.

Sell Wastewater Reclamation

Graphic representation of NuWater’s water reclamation and reuse procedure

dela s costly. delays costl We have ha e built b ilt a wealth ealth of expee pe rience through successful projects delivered to date and have earned the trust of demanding customers such as Anglo American and Gold Fields,” Holmes outlines.

In late 2010, NuWater was awarded a BOO project for the provision of a water treatment and desalination solution of up to 20 000 m³/d for Anglo American Thermal

In mid-2012, Gold Fields selected NuWater to provide two of its rapidly deployable modular plants for its Tarkwa operations in Ghana

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Inside Mining 05/2013

Coal’s Ne New Vaal collier colliery, near Vereeniging Vereeniging.

NuWater proposed its completely ‘modular & mobile’ plant, which enabled it to have the first treatment capacity commissioned within weeks of contract signing. Treatment capacity was then ramped up over the next three months through the addition of further modules.

The modularity of the plant allows capacity to be added or removed with minimal, if any, impact on day-to-day treated water production. The high-quality product water produced by the NuWater plant at New Vaal is pumped to the neighbouring Eskom

Lethabo power station for use as cooling water, further enhancing the environmental credentials of the project. The initial twoyear contract period is now being extended by a further three years.

In mid-2012 Gold Fields selected NuWater, together with Murray & Roberts, to provide two rapidly deployable modular plants, one treating 2 700 m³/d and the other 7 200 m³/d, for its Tarkwa operations in Ghana. Once again, the modularity and mobility of the NuWater plant was a key factor in the selection process along with the sense of urgency and client commitment displayed by the NuWater team. Gold Fields also benefited from NuWater’s ability to deliver different parts of the plants at short notice from its operations in South Africa, Singapore and the UK. “Furthermore, our ability to offer commercial flexibility through a combination of equipment rental, equipment sale, and operations and maintenance services has allowed Gold Fields to achieve a fast and cost-effective solution to its water treatment requirement.”

Interest from new clients in NuWater’s ‘modular & mobile’ solutions continues to grow as the benefits of both technical and commercial flexibility become more obvious.

Extension of the company’s product offering to cover brine treatment and acid mine drainage applications is also putting it in the best possible position to provide complete mine wastewater treatment, reclamation and reuse solutions and services to address the most challenging requirements.

In each issue, Inside Mining offers advertisers the opportunity to promote their company’s products and services to the appropriate audience by booking the prime position of the front cover which includes a two-page feature article. The magazine offers advertisers an ideal platform to ensure the maximum exposure of their brand. Please call +27(0)11 465 5452 to secure your booking.

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 Hot seat

TACKLING TAILINGS

Managing mine waste in Africa The world is demanding greater awareness and environment preservation action from large-scale industries. For the mining sector, this means paying attention to one of its largest environmental exposures and liabilities: mine waste. Golder Associates examines the greatest challenges, emerging trends and best practice applications for mine waste – tailings in particular. Laura Cornish reports.

G

older’s environmental consultation, engineering design and construction expertise, coupled with its vast global mining engineering-focused business, facilitates a specialised focus on all tailings facility aspects – from

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Inside Mining 05/2013

design and facility development through to construction, operational management, closure and rehabilitation.

Thanks to the onset of more stringent mining environmental legislation and the implementation of global best practices, this

business area is seeing considerable growth, not only in South Africa, but throughout the African continent.

“We are not a general civil engineering company; we concentrate and specialise in key market sector areas, which for the mining

 Hot seat sector include water supply, wastewater, mining infrastructure, geotechnical engineering and project management for largescale projects,” highlights Golder’s head of engineering services, Charles Naidoo.

The company’s Ground Engineering Division incorporates tailings and mine waste management. Principal and strategic advisor to engineering, Francois Marais, outlines Golder's three ground engineering sub disciplines: tailings delivery schemes such as pumps and pipeline systems surveillance, which involves tailings facility monitoring – the ongoing monitoring of tailings facilities in terms of structural integrity, Golder's performance against design intent and environmental exposure, and tailings facility designs.

the tailings stream management, which ultimately boils down to implementing the correct and appropriate technology for the application in question,” Marais acknowledges. “Our ultimate aim is to demonstrate that we can add value to unlocking the unmined prosperities and resources in Africa by ensuring mine waste and tailings management is

the development and operation of a tailings facility has the potential to have the largest environmental impact, we are sensitive in our design approach and apply only the most viable design technologies e.g. engineering barrier systems that would pose minimum risk to the receiving environment,” Marais notes.

“The fundamental discipline for tailings engineers is geotechnical engineering; however, we believe the success of this nurturing process is through project exposure – experience is key.” Francois Marais

Tailings – an increasingly significant role “The viability of a new mine is influenced by the feasibility and cost-effectiveness of Finsch tailings storage facility

A case study: New South Deep New Doornpoort tailings storage facility • Golder was leading design and implementation consultant.

• Golder completed this 20-month R387 million project on time and within budget, meeting all the client deadlines.

• Excellent safety record with working over 1.6 million man hours lost-time injury free.

• Over 4 million cubic metres of earthworks, 35 km of steel HDPE pipelines, four motorised control centres, three pump stations and 14 ha of HDPE lining for 1 million cubic metres of return water dam.

• Golder manages 10 sub-consultants and two main contractors.

• Project manager: André Richardt – head of integrated project management at Golder.

conducted in a responsible and environmental sustainable manner,” Naidoo adds.

Mining companies are looking to consulting experts who understand and offer the full suite of tailings technologies and methodologies, and are clearly showing a preference for companies capable of offering the full ‘cradle to grave’ service, from characterisation of the tailings for new facilities, including feasible designs, through to tailings closure planning. Companies with comprehensive knowledge and understanding of all tailings aspects are benefiting in today’s new, environment-conscious world.

“Golder tailings experts don’t only have a thorough knowledge of all current tailings technologies and practices, but further acknowledge that technology ranges are directly linked to how tailings/slimes/slurries are ‘densified’ through physical and chemical treatment, for example dewatered or thickened, before being pumped and disposed onto a tailings facility. Knowledge of all deposition methodologies, including cycloning and paste depositioning, dewatered and solid mine waste disposal is an asset,” Marais says.

And, while the construction and management of tailings facilities have always presented environmental challenges, there are several major challenges and concerns the industry is currently facing and addressing, which Marais outlines.

Golder’s tactical method is to apply a quantified modelling approach, which simulates the tailings source, the seepage pathway and receptors within the zone of influence of the tailings facility. “This enables us to quantify the impact of the tailings facility in terms of acceptable risk levels.”

Understanding in-country standards From an African perspective, the interpretation and comprehension of specific incountry standards is another great challenge. Fortunately, thanks to specialised input from its vast array of international colleagues, such challenges are easily overcome, “especially if we are involved in the full design process for a typical tailings facility, which includes feasibility studies, detailed designs and overseeing implementation of the facility in terms of quality control, contract administration, site supervision and project management”.

Golder also has teams in place that conduct quarterly and annual inspections and audits on existing tailings operations. Marais says that this surveillance service must be in compliance with in-country legislation and international best practices.

“Regardless of country or client, we want them to know that together we can find solutions to operate in a sustainable, environment-respecting manner,” Naidoo reiterates.

Meeting international best practices “Ensuring that the design process for a new tailings facility meets international best practice is one of the industry’s greatest challenges. Investment companies in mining developments nowadays expect only the most viable, sustainable and environmental defensible standards. Because we recognise that

Reducing closure liabilities Marias identifies that “using defunct opencast operations for tailings disposal has become an attractive option for viable tailings disposal and at the same time reducing closure liabilities. The challenge, however, is to do so in an environmentally

Inside Mining 05/2013

9

 Hot Seat Golder’s presence in Africa Golder’s presence in Africa is already well established in certain regions, but is likely to continue growing as mining development expands and environmental legislation escalates, resulting in a greater need for environmental engineering consultants.

According to Naidoo, the company’s exposure in West Africa is vast, particularly for its tailings, geotechnical engineering and mining infrastructure services. “We are also active in Mozambique’s Tete and Maputo areas as well as in Botswana – again, providing various tailings and mine waste activity services. Outside of these two coal regions, we also have a strong project presence in the Democratic Republic of the Congo, Ethiopia and Zambia.”

ABOVE South Deep tailings storage facility BOTTOM LEFT Ensuring that the design process for a new tailings facility meets international best practice is one of the industry’s greatest challenges BOTTOM RIGHT Mining companies are looking to consulting experts who understand and offer the full suite of tailings technologies and methodologies

acceptable manner.” Golder personnel are often involved during closure and post-closure design activities where tailings engineering, specialised technology and scientific knowledge is required.

New engineering generations “Growing and nurturing young and upcoming engineers into these specialised areas requires dedication. The fundamental discipline and feed source for tailings engineers is geotechnical engineering; however, we believe the success of the nurturing process of young engineers is through project exposure – experience is key,” says Marais.

Emerging trends Marias acknowledges that some of Golder’s clients are forming joint venture consortiums for large-scale reclamation projects, particularly in the gold- and uraniumfocused sectors. “The focus has also shifted from the East Rand to the far West Rand

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Inside Mining 05/2013

in Gauteng. Companies are driven by improved processing and beneficiation technologies, an attractive gold price and the anticipated shortage of uranium in the nearby future. “The long-term environmental benefit of large-scale tailings reclamation projects is footprint clean-ups of current tailings facilities.” The technology challenges are to reclaim, reprocess and

and financial benefits, as lower grade coal waste material is now being considered for coal-fired power station applications.

Power plant technology is being upgraded specifically to take on lower grade coal materials.” Marais says up to 30% of run of mine is currently classified as coal mine waste materials.

In Africa, particularly the emergence of

“Our ultimate aim is to prove that we can add value to unlocking unmined prosperities and resources in Africa by ensuring they will pose little or no threat to the environment.”

Charles Naidoo

transport large tailings tonnages and to develop new mega tailings storage facilities to ensure that these projects are viable”.

The coal industry also has much to gain from the correct handling and management of its slurry and coal discards. “When slurry and coal discards are handled properly within well-planned and designed facilities, opportunities could open up to reclaim these waste sources as future products. This has substantial environmental

new coal mines in Mozambique, coal waste rock volumes are extremely high due to high overburden stripping ratios, to expose thicker coal seams. This is leading to the establishment of large-scale waste rock dumps, which can be equally as hazardous to the environment as tailings facilities if not designed, built and managed properly.

“Water and seepage management is essential to minimise potential environmental impacts from coal waste rock dumps.”

 Hot topic

ENGINEERING EVOLUTION

WorleyParsons and TWP take the WorleyParson’s acquisition of TWP Holdings marks the beginning of a new engineering era. Together they form one of the world’s African continent’s largest engineering houses, setting the new standard for the entire engineering fraternity, writes Laura Cornish.

M

ultinationals want to work with single multi-skilled, large-scale engineering entities with worldwide exposure and capabilities,” says Nigel Townsend, former chairman of TWP and new Customer Sector Group executive for the WorleyParsons minerals, metals and chemical customer sector group.

The merger between the global engineering group and the local mining engineering expert is not only delivering to this exact need, but represents the start of a new era as multiple engineering houses are following suit.

Francis McNiff, regional MD for WorleyParsons sub-Saharan Africa, reveals that the company had been looking to expand its minerals, metals and chemicals division outside of Australia for a number of years. It is also no secret that TWP had been pursuing its global growth strategy aggressively and while it had some success, it required the backing of a major global entity such as WorleyParsons to fulfil its aspirations completely.

“Our mining strengths lie predominantly in bulk commodities such as iron ore and base metals, predominantly in Australia.

Our acquisition needed to fulfil two areas: geographical footprint expansion (particularly in Africa and South America) and a

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Inside Mining 05/2013

more diverse service offering. TWP’s forte lies in underground mining development and precious metals processing. We believe these two areas hold a lot of promise for growth and opportunity for the entire WorleyParsons Group,” McNiff outlines.

And because both companies bring such different strengths to the table, their capabilities complement each other perfectly.

“Together we will execute large, complex projects without limitation by leveraging and exploiting our best strengths and skills under one umbrella.”

the infrastructure and environment fields, the addition of a strong mining arm allows it to offer the full pit-to-port service, using South Africa’s competitive cost base.

South Africa still remains the business gateway to Africa, especially from a pricing perspective. Mining currently represents about 10% of WorleyParsons’ business. Its only current major mining project in South Africa is the full EPCM contract for Sasol Mining’s Shondoni brownfields expansion. “We are, however, also involved in a number of small projects and studies,” McNiff mentions.

WorleyParsons TWP The newly branded WorleyParson’s TWP company will represent the WorleyParsons Group’s global mining hub/centre for underground mining and precious metals processing going forward; all new projects will be executed from South Africa.

The former CEO of TWP Holdings, Digby Glover, has been appointed COO of WorleyParsons RSA, which includes WorleyParsons TWP. As a large-scale global entity with more than 40 000 employees spread across 41 countries, WorleyParsons has first-class, advanced systems and processes that will further enhance its new mining hub’s service suite. And because it is strong in both

The longer-term future “The acquisition will ensure our global strategy is on the right path - achieving balance in the minerals, metals and chemical fields. We believe the minerals and metals fields will be a fundamental pillar of our business,” McNiff points out. “We will bring robust systems and tools that Nigel Townsend, Francis McNiff and Digby Glover

kn

The same water that existed on the earth millions of years ago is still present today, but now has to stretch to meet the needs of seven billion people. o

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can deliver from small to the large. Our ability to move people around the world, bring the necessary proven capability to where it is needed, share skills from multiple locations, manage costs and workload is what gives us our competitive edge.”

WorleyParsons’ acquisition of TWP has delivered it with a healthy mining projects portfolio. The company has numerous shaft sinking projects under way; its most recent EPCM contract is for the underground expansion development of De Beers Consolidated Mining’s Venetia kimberlite.

“We are busy with a variety of feasibility studies and our current project portfolio is solid,” Townsend notes. “Underground mining is growing increasingly attractive around the world, which ensures steady, longer-term access to minerals and is considered more environment-friendly.”

Everything Absolutely Under Control.

From beginning to end, any project needs critical attention to detail. Our sound governance, monitoring, control and organisation will ensure your project is successfully executed.

ABOVE TWP's experience in underground development is globally recognised BELOW TWP specialises in precious metals processing

Call us, or visit www.twp.co.za TWP South Africa T 0861 TWP TWP (SA) / +27 11 218 3000 E twpinfo@twp.co.za

 Diamonds & gems

KAROWE

A truly rare and spectacular find Every diamond miner hopes to find a unique or rare diamond in their asset.

Fortunately, for diamond junior Lucara Diamonds, a member of the Lundin Group of Companies, its flagship mine Karowe keeps revealing such gems, writes Laura Cornish.

F

rom 2012 until now, it has been an exceptional and transformational period for Lucara Diamonds (Lucara). It will soon celebrate its first year of production, which began with the commissioning of its Botswana-based, 100% owned Karowe mining project (AK6 kimberlite and process plant). The real celebration, however, is the recovery of some exceptionally rare and large-carat diamonds.

On 10 March, Lucara recovered a 239.2 carat diamond from Karowe. In addition to the recovery of this exceptional gem, two more large stones weighing 124 carats and 71.1 carats have also been discovered. The diamonds were recovered from the central kimberlite domain, which has only recently become ore feed to the plant as the pit expands towards the south.

The diamonds are currently being studied prior to being sold later in the year. “The recovery of these large stones is hugely significant to both Lucara and Botswana. To the best of my knowledge, the 239 carat stone is one of the largest diamonds ever to have been recovered from the highly prolific Orapa kimberlite field in over 40 years of production. The recovery of a diamond of this size and the strong operational performance in our first few quarters of operation demonstrate the quality of the asset as well as the competence of the operations team,” says Lucara’s president and CEO, William Lamb.

The recovery of such a magnificent story has already made company history,

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Inside Mining 05/2013

especially considering there were no largescale stone predictions from any of the exploration samples. “It is the rare occasions such as this that remind me why I find diamond mining so exciting.”

Some would consider the 239 carat Karowe diamond a ‘cherry on the cake’.

The mine, however, started revealing its true unique potential late last year. In October and November 2012, Lucara recovered two rare sky blue diamonds, weighing 9.46 carats and 4.77 carats, respectively.

The larg-

er stone was sold in November, bringing in US$4.5 million (R40.36 million) – indicating just how much the market loves them, Lamb points out. “The recovery of the 4.77 carat blue diamond, which was sold in March for US$1.6 million, brings the total number of blue diamonds recovered in the past few months to four.” The impact of these rarities on Lucara’s cash flow is significant.

While the Karowe process plant, comprising dense media separation and X-ray, is

still in its infancy, the retrieval of such valuable stones has already seen Lucara relook and re-evaluate its plant design. “Our plant was only ever designed to recover typical run-of-mine material. We have, however, already started a programme to evaluate what changes need to be made to the plant and how to change the process stream slightly to accommodate the possibility of recovery of bigger diamonds,” Lamb discusses.

Lucara is in the process of transferring a Russian Bourevestnic high capacity X-ray machine from its Lesotho-based Mothae project (currently on care and maintenance), which Lamb believes will help evaluate how best to alter Karowe’s circuitry process.

The Karowe plant has been designed to process 2.5 Mtpa of kimberlite, producing 400 000 carats a year.

The pipe actually consists of three separate kimberlites: a central, northern and a southern lobe. The centre lobe will be mined over the next four or five years and is showing high-grade, large white stone proportions.

North lobe grades are slightly higher with the quality of the diamonds being lower by comparison, while exploratory predictions for the south lobe (70% of total kimberlite) reveals slightly “smaller” diamonds.

Lamb’s expectations for Karowe remain high in the long term. Not only is the pipe open at depth below 758 m, but the proportion of Type IIA diamonds recovered during exploration came from the south lobe, including a population of pink and purple

LEFT One of the rare sky blue diamonds recovered from Karowe ABOVE 239 carat recovered from Karowe BELOW Karowe DMS plant

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diamonds and smaller blue stones. “This increases the probability for recovering larger, coloured stones from this area as well,” he says.

“Karowe has delivered beyond expectations in every regards and has established itself as one of Botswana’s premier diamond producers in just eight months,” Lamb exclaims. During 2012, the project produced a total of 303 000 carats from 1.4 Mt of ore, exceeding guidance by 12%. Proceeds from the sale of nearly 216 000 carats totalled US$55 million, resulting in an average sales price of US$253/carat – also exceeding yearend expectations. During the first quarter of 2013, the company sold 144 712 carats of Karowe diamonds for gross proceeds of US$32.5 million. The 2013 sales included six parcels totalling 18 233 carats, which were withheld from the December 2012 sale due to low volumes of competitive bidding.

Lucara anticipates holding eight sales (two per quarter) in 2013. The sales are anticipated to average 50 000 carats of diamond each and there will be client viewings conducted in both Gaborone and Antwerp.

“Because this is Lucara’s first greenfield mine project, we are risk-averse. We have a highly skilled staff complement of 87 people who are making the main decisions and

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 Diamonds & gems

have all been involved in the development of other diamond projects. Senior management portfolio’s alone includes eight different diamond projects.” Contractors provide bulk of labour and include plant operator Minopex and WBHO local subsdiary Kalcon, which is responsible for mining.

Mothae Lamb likens the company’s second asset, the Lesotho-based Mothae, to the famous Letšeng pipe, also in Lesotho.

Mothae Diamonds, which is owned 75% indirectly by Lucara through Mothae Diamonds Holdings and 25% by the Lesotho government, holds a 100% interest in the

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Mothae project. It comprises a number of kimberlite blows and contains large Type IIA stones. A trial mining programme was completed in September 2012 with final processing of hard, unweathered kimberlite from the central resource domain of the south lobe. This brings the total tonnage sampled from the Mothae kimberlite for economic evaluation purposes to 603 819 dry tonnes, yielding an average sample grade of 3.88 cpht.

Diamond sold from Mothae have demonstrated the potential for the kimberlite to deliver high value goods. In the first two held, the average diamond price exceeded US$870/ carat, with the highest value

Inside Mining 05/2013

15

 Diamonds & gems LEFT Karowe opencast mine INSET 239 carat recovered from Karowe

which is clearly a step in the right direction and we are confident of the outcome. We are, however, investigating alternative solutions to find a viable way to take this project forward,” Lamb outlines.

Further growth following the completion of its trial mining programme. “The project’s biggest hurdle is power. We need a 60 km power line to deliver between 10 and 12 MW of power to site. We are not in the position to provide the enor-

The 239 carat stone is one of the largest diamonds ever to have been recovered from the Orapa kimberlite field in over 40 years of production diamond sold being a 28.9 carat stone that sold for more than US$57 000/carat.

The company is currently reviewing a number of development options for Mothae

mous capital outlay for such infrastructure requirements. The new minister of mines, however, is lobbying heavily with the minister of energy for countrywide infrastructure,

“Karowe is providing us with a revenue stream enabling us to look at other opportunities to expand our portfolio. I am particularly keen on partnering with other juniors at the advanced exploration level.”

While most diamond experts have indicated that the chance of discovering a new and viable kimberlite pipe is almost non-existent, Lamb has his own theory. “Full-scale kimberlite exploration last occurred in the Orapa district at least 40 years ago and while many discoveries then were considered unviable, I believe some of those areas should be revisited. Economics have changed, indicating the possibility for projects that were once considered unfeasible to be feasible today. The AK6 kimberlite is a good example of this.”

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 Diamonds & gems

GEM DIAMONDS

A big expansion on a minimal

A weak, financially constrained economy continues to see mines retain their cash conservative status. The situation, however, has seen Gem Diamonds rise to the occasion, writes Laura Cornish.

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here is an upside to financially depressed global economic conditions.

It forces us to evaluate alternative methods with which to deliver similar targets and aspirations, with significantly smaller cash budgets,” Gem Diamonds’ CEO, Clifford Elphick, points out.

Elphick is specifically referring to its 70%-owned Letšeng diamond mine, situated at the highest point of Lesotho’s Maloti mountains. In January 2012, the company commenced with project Kholo – an expansion intended to almost double the mine’s run-of-mine (ROM) output from 5.6 Mtpa to 10 Mtpa with the addition of a third process plant, increasing carat production from just

over 100 000 to around 200 000 ctpa.

While economic conditions have seen the mine’s expansion plans change route significantly, the objective remains the same.

“Regardless of the world’s financial markets, we are driven to strengthen our position as a global leader in the supply of high-quality diamonds. This has forced us to review our expansion plans and find alternative ways to achieve similar results with the smallest amount of cash necessary,” Elphick continues.

So project Kholo remains in progress, only now it consists of a variety of smaller-scale processes and procedures – at both mine and plant – that will increase ore throughput,

 Diamonds & gems

budget

LEFT Letšeng main pipe ABOVE Large diamonds recovered at Letšeng

completed an enhanced and upgraded security system with measures to ensure that no carats leave the property unaccounted for.

“We have now combined upfront screening of our personnel to determine their risk profile, based on behavioural traits with further regular polygraph testing in the recovery plant. We have also changed our security service provider and incorporated biometric finger printing into our access control. All of the security cameras have also been upgraded into high resolution state-of-the-art cameras,” Elphick reveals. All high risk areas will be controlled with much improved access control generally.

Step two: Addressing diamond damage

improve diamond liberation, reduce diamond damage and increase the amount of production available for cutting and polishing. The optimised Kholo project will not achieve all of the goals of the original Kholo project but will approach this on a ‘piece meal’ basis.

“While the decision to abandon the construction of an entirely new, state-of-the-art third plant and recovery is sound, we believe we can still reach 7.5 Mtpa.

Letšeng is globally recognised for its large, high-quality diamonds and has a high occurrence of Type II diamonds, which are brittle and prone to damage, particularly with the current on-site crushers.

Following studies in Japan, Gem Diamonds has acquired four new Kawasaki Cybas i1200 crushers, which have been specifically configured to the mine’s ore characteristics. They are already on route to site and will be commissioned by the end of the second quarter of 2013.

“We are expecting better diamond liberation, with recirculating loads being dramatically reduced and far less damage to our diamonds, which ought to immediately lead to increased revenues,” Elphick points out.

The new project Kholo Step one: Improving security measures

Step three: Incorporating new technologies

It is a simple fact that theft is one of the major diamond mine challenges. To reduce this risk further for Letšeng, Gem Diamonds has

Elphick is expecting to achieve positive results following the incorporation of new diamond recovery technologies into its process.

“We are currently undergoing feasibility studies using X-ray transmissive technology (XRT). Because our Type II diamonds have low fluorescence properties, they are sometimes missed using our current technology.

The incorporation of XRT in combination will ensure we recover as close to 100% of our Type II diamonds as possible.”

Letšeng conducted tests on this and other technologies for about six months and recovered a number of diamonds from its tailings, which achieved US$12 million (R111.07 million) in revenue. XRT will enable the mine to recover large, high-value diamonds early on in the recovery process, which reduces the chance for damage.

Another technology avenue Gem Diamonds is pursuing is near infrared waste sorting, which has the potential to reduce internal and external waste dilution by as much as 25% in some facies. “By removing basalt waste material, more space is obviously made available for diamond bearing ore in the recovery plant,” Elphick explains.

The mine is currently testing the technology on-site, which it will complete at the end of the year.

The Letšeng mine consists of the Main and Satellite pipe. While Elphick admits that the grade from its Main pipe (which comprises 75% of total annual production) has dropped slightly to between 1.6 and 1.7 cpht, the combination of its long lifespan and ability to deliver large, top colour, exceptional white diamonds will ensure it retains its ‘top star’ status, especially as prices increase and global diamond resources deplete.

Ghaghoo The development of its second kimberlite project, the underground mine at Ghaghoo, located in Botswana, continues to make steady progress. “We are slightly behind schedule due to two fatalities on-site late

Inside Mining 05/2013

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 Diamonds & gems Autogenous mill arrival at Ghaghoo

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last year. We immediately suspended tunnelling activities while the accident investigation was being completed W atch and have now incorporated r e at additional safety measThe total ures, which have slowed amount of water down the decline tunnel on the earth is development rate.” about 326 million cubic miles.

The process plant, howi d ever, is 90% complete and

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incorporated into the decline to compensate for the soft Kalahari sand in the area.

Once operational, Gem Diamonds will implement a phased approach to evaluate the full potential of the mine. Phase 1 sees Gem Diamonds fully understand the ore body characteristics in terms of real grade, real diamond price and market demand. Phase 2 is based on the results of Phase 1 and will look at an expansion (either doubling capacity or slightly more). The current plant has been designed to treat approximately 700 000 tpa.

“It’s a nice big ore body, which has been well sampled and drilled.”

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the camp is finished. Water storage dams, slimes facilities and support services are also in place. “We anticipate reaching the ore body at the end of the first half of 2014, with first carats delivered towards the middle of 2014.” Ghaghoo’s average grade is expected to be about 26 cpht. Just over 400 m of the access decline through the Kalahari sand has been developed – of 550 m in total. A unique cement ring lining has been

Beyond Letšeng and Ghaghoo Following the sale of its Ellendale mine in Australia, Letšeng and Ghaghoo remain the only two African assets in the Gem Diamonds portfolio.

“Our immediate strategy is to produce sufficient cash flows to begin dividend payouts to our shareholders. We have a preference for organic growth and that is our focus for the immediate future.

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 Diamonds & gems

THE LOVELY LACE

DiamondCorp’s leading lady

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The Lace diamond mining project is possibly one of the last remaining lucrative kimberlites in South Africa. In addition to its attractive carat content, production start-up is due in 2015 – the first year that diamond demand is expected to exceed supply, writes Laura Cornish.

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Inside Mining 05/2013

SE/AIM-listed diamond junior DiamondCorp has travelled a long road since acquiring the non-producing Free State-based Lace project in 2005. Although once an operational mine (from 1908 to 1939, producing 750 000 carats at 16 cpht), a well-thought-out mine design, development and production schedule programme has been re-established to ensure that the road to production is smooth and maximum carats are obtained for minimal cash. Even its final barrier – raising sufficient funds to implement the underground development plan – has been broken through and the journey to production begun.

The company’s CEO, Paul Loudon, has spent years indicating the projects attraction and has spoken of its lucrative gemlike quality stones, including rare pink and lilac stones.

ABOVE The original opencast Lace pipe, now completely dewatered LEFT Lace is known for its rare pink and lilac stones BELOW DMS plant

The road to project start-up Considering the impact of the global economic crisis, and its ongoing effects on the market’s ability to raise cash, DiamondCorp has made remarkable progress. Not only has it raised sufficient capital for its development requirements, but has already completed the construction of its 200 tph dense media separation (DMS) plant, which is currently being tweaked to shift from tailings retreatment to underground material processing. Following the conclusion of its final finance deal in January this year, the company kick-started its underground development.

On 7 January 2013, DiamondCorp

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About 43% of South Africa’s Unlike most new diamond rainfall is on 13% of start-up projects, Lace the land and only 9% already has an extensive of that reaches our operating history. Around rivers.

4 Mt was mined from near yo surface to about 350 m Did underground at 16 cpht until the mine was closed in the Great Depression then sold to De Beers, which allowed the mine to flood in the 1940s as part of its long-term control of diamond supplies.

The recovery of gem-quality diamonds has, however, been demonstrated by tailings retreatment and from processing an underground bulk sample. The company has employed a strong, experienced diamond development and mining crew, which has put together a ‘robust’ development plan.

DiamondCorp’s 74%-owned 1.2 Mtpa runof-mine (ROM) Lace mine is scheduled to produce up to 550 000 carats each year for 25 years, starting in 2015. The Main pipe alone contains 33.1 Mt of kimberlite indicated and inferred to a depth 855 m containing approximately 13.4 million carats in both resource categories at an average grade of 40.1 cpht.

This equates to an ‘in-ground value’ in excess of US$2 billion at US$160/carat.

The construction programme is to develop a relatively low-cost continuous trough block cave ‘production’ level at a depth of 470 m (47 Level), which should take between seven and 10 years to mine. Following this, the development of new block cave at 650 m (65 Level) and 870 m (87 Level) will follow, which will take the mine to the end of its life (based on its current resource).

“Because the grade improves as we go deeper, one of the challenges to our mining model is finding the best way to smooth out the saw tooth shape of our production curve as we transition between each of the three planned

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signed binding legal agreements with Laurelton Diamonds, a wholly owned subsidiary of Tiffany & Co for a term loan of US$6 million (R53.59 million) in exchange for an off-take agreement for diamond production from Lace. Combined with the Industrial Development Corporation’s R220 million finance facility, Lace is now fully funded through to first diamond delivery.

And the company is not holding back; activity on-site is under way and development targets an absolute priority.

Developments include: • The construction of a new 66 000 m³ boxcut, providing the surface entrance for twin conveyor belt, and men and materials declines, and the completion of a vent raise from 16 Level to provide sufficient interim ventilation for continuous blasting decline development until LOM vent shafts are raise bored.

• Installation of a tipping arrangement on 24 Level to allow loading of waste generated from the twin decline development down to the 47 Level. Until 2.6 km of conveyors are installed, development waste will be hauled out of the mine by low profile dump trucks (these are already on-site).

• Essential upgrades to the dense media separation plant to alleviate front-end bottlenecks in the re-crush circuit at fullscale production. Completion of these upgrades will also allow tailings retreatment to recommence. The kimberlite is harder than originally anticipated, which is good for tunnelling; doesn’t hold water and has very high rock strength. The downside, however, is that it requires more energy in the comminution circuit to break down the kimberlite material.

• Completion of detailed design drawings for the underground conveyor belts.

• Definition drilling of a bulge from within the kimberlite bulk sampling area on the 260 m level.

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 Diamonds & gems

Inside Mining 05/2013

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 Diamonds & gems

ABOVE Underground development is rapidly processing at Lace

block caves. To provide production flexibility, our conveyor capacity from underground will be 400 tph – double the front end of the plant – and we will look to use low grade stockpiles to try and smooth out the curve.”

It is the project’s long-term prospects, however, which Loudon speaks of most enthusiastically. “Our margins will increase over the mine’s lifespan as our grades increase

significantly at the deeper levels, to between 50 and 60 cpht. The project is furthermore open at depth, meaning we have yet to discover the viability and diamond content and quality below 855 m,” Loudon indicates.

Furthermore, because of the unusually hard nature of the kimberlite, Lace is less likely to suffer traditional kimberlite mining challenges. “Because our kimberlite is very slow to absorb water compared with other mines, the potential for mud rushes, which is a perennial operational challenge in underground diamond mining, should be reduced. The high rock strength will also be a major advantage in setting up a trackless block cave, a mining method which itself should further mitigate the mud rush risk,” Loudon reveals.

At present The DMS plant is on the brink of start-up and will recommence with tailings processing in the interim in preparation for underground material. The plant was previously processing the tailings, which was stopped when diamond prices plummeted in 2008. Lace still has over 3 Mt of retreatable

tailings remaining. A new power line has been installed to Lace neighbour Voorspoed, which has also been connected to Lace – the only other user. There are currently 100 Lace employees on-site, which will ramp up to about 300 in due course.

“We have already purchased most of the machinery required to run the mine, including trucks, drilling equipment and loaders.

We have a fully equipped machine workshop repairs and spare parts facility with qualified staff who can take the machines through full rebuilds. We are extremely proud of this component of our operation, which makes us almost fully sustainable on our own.”

Good timing Industry experts are predicting that diamond demand may start to exceed supply in 2013; however, the world will likely only start feeling the effects in 2015. For a new and incoming kimberlite mine player, an alignment between production start-up and a supply deficit could not be better timed.

“The industry is already at peak diamond production, meaning the long-term metrics for Lace are extremely strong.”

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 Diamonds & gems

TRUE BLUE

Another gem from Cullinan On 17 April, Petra Diamonds announced the recovery of a 25.5 carat blue diamond from its Cullinan mine – the most famous source of blues in the world.

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26.6 carat blue carat diamond of this nature was last recovered from Cullinan in 2009. The rough blue diamond yielded a 7.03 polished stone, which sold for US$9.49 million

(R87.16 million) – or US$1.35 million/carat – at a Sotherby’s auction. At the time, this was the highest price per carat for any gemstone sold at auction and the highest price for a fancy vivid blue diamond sold at auction.

VENETIA

The ancestral heart of De Beers Pit bottom at Venetia

The De Beers Group of Companies will invest approximately R20 billion in a new underground mine beneath the currently operating opencast Venetia mine in Limpopo.

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hen completed, the new underground mine will extend the life of Venetia beyond 2040 and replace the open-pit as South Africa’s largest diamond

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Inside Mining 05/2013

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STRATEGIC PARTNERS

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The United States uses about 346 mine.

This announceBeers is celebrating its 000 million gallons (1.3 ment follows the receipt 125th anniversary this year. trillion litres) of freshwater of the final outstanding From our founding in Kimevery day, 80% of which is regulatory clearances. berley in 1888 to today’s used for irrigation and The development and announcement at Venetia, thermoelectric power. build phase of the underSouth Africa has always been o y ground mine is expected to the ancestral heart of De Did create 1 000 jobs over the next nine Beers. It is gratifying that this project years while opencast mining operations will enable De Beers to remain one of the continue. Underground operations will leading diamond companies in South Afribegin production in 2021. The life of mine ca until at least our 150th anniversary.” plan contains an estimated 96 million carPhillip Barton, CEO of De Beers Consolats in approximately 130 Mt mined. idated Mines, adds: “The Venetia project The project is expected to employ more team has been assessing the safest and than 3 000 semi-skilled and skilled workmost economic options to extend the miners, drawn primarily from the region and ing operation and unlock the extensive ore trained for the project. Those trained will reserves beneath the open pit. Venetia will mostly acquire technical skills that will enplay a major role in the future of De Beers hance the country’s technical skill resource and we have therefore been preparing for base. The bulk of all equipment and servicyears to meet tight deadlines and high es will be sourced in South Africa. standards so that Venetia Underground is Philippe Mellier, CEO of the De Beers ready to begin producing South African diGroup, comments: “It is fitting that De amonds by 2021.”

ROCKWELL DIAMONDS

Kissing Klipdam goodbye Rockwell Diamonds has reached an agreement to sell its Klipdam mine and associated properties to a private alluvial diamond miner for R23 million.

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his brings the total proceeds from the sale of this asset to R48 million, including the sale of the earth moving equipment in October 2012. The proceeds will be reinvested in bringing the Niewejaarskraal mine into production and progressing with its strategy to grow its operating footprint in the middle Orange River region of South Africa.

Under the terms of the agreement, Rockwell will retain ownership of certain items of plant and machinery that will be redeployed, chiefly to Niewejaarskraal.

James Campbell, CEO of Rockwell, elaborates on the rationale for the transaction: “Klipdam mine has a remaining life of two years, based on current resources. We accepted the offer for this mine, as opposed to investing further resources to extend

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W of the97% delivering on our stated obseparation (DMS) plant at earth’s jective of growing monthNiewejaarskraal back into water is in the oceans.

Only 3% of the earth’s water ly production volumes operation. The DMS procan be used as drinking water. to 500 000 m3 from duction will be supple75% of the world’s freshwater our existing inventomented through the addiis frozen in the polar ice caps. ry of properties in the tion of four 16-foot rotary Over 6 billion people Middle Orange River pans from the Tirisano mine share the remaining region. With three proin addition to using equipwater. u y o ductive mines, namely Saxment from Klipdam that was Did endrift; the Saxendrift Hill comnot part of the sale. Trial mining opplex, which is in the production ramp-up erations are expected to come on stream afphase; followed by Niewejaarskraal, we ter a six-month implementation phase with expect to reach three quarters of this tara six-month ramp up to a monthly processget,” Campbell states. ing capacity of 115 000 m3.

The production team from Klipdam has “The Niewejaarskraal deposit average the requisite expertise and experience to grade is 0.74 carats/100 m3 and has the potential to produce higher recovery grades efficiently run a pan and DMS plant and than Saxendrift, with the added benefit will be relocated to Niewejaarskraal, as will of slightly better projected average carthe contract miner CML Operations. As at values. Our plans for Niewejaarskraal part of the design phase, Rockwell evalalso make use of the existing production uated the potential for a second phase of plant and equipment without placing uncommissioning to increase the capacity of due pressure on our capital resources. We Niewejaarskraal to 200 000 m3; this option will be revisited once the initial phase has believe our track record in the middle Orbeen bedded down. ange River region positions us to start de“The Niewejaarskraal development is livering positive net returns by the end of another important milestone towards fiscal 2014.” kn

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its projected mine life through additional exploration, because our analyses projected higher long-term returns from Rockwell’s middle Orange River properties, which have better grades and diamond values than Klipdam and yield high-value, gem-quality diamonds.”

At the same time, a proposal to take the Niewejaarskraal mine out of care and maintenance has been approved, with a total capital budget of R20.1 million that is comprised chiefly of labour and earthworks. The project entails bringing the dense media

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CRYSTAL-LIKE ANDALUSITE

A mineral changes a community Contrary to widespread misconceptions that mining is an industry that does not benefit the communities situated around mining operations, Imerys South Africa is proving otherwise, writes Reggie Sikhakhane.

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rance-based industrial minerals company Imerys, through its South African mining subsidiary, Imerys Mining and affiliate Rhino Minerals, officially opened its Annesley andalusite mine in Burgersfort, Limpopo,

LEFT Annesley process plant

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Inside Mining 05/2013

 Diamonds & gems

ABOVE Chamber of Mines CEO Bheki Cele was among invited delegates at the event RIGHT Housing for the community included running water and electricity, built

by Group Five LEFT The process plant is situated near the opencast mine

completion of the houses has been a long and arduous 12-year journey, but finally both the community of Segorong and Imerys South Africa have a good reason to celebrate,” says Imerys’ CEO and chairperson, Gilles Michel.

Having gone through all the necessary steps and requirements set out by the Department of Mineral Resources – including social responsibility aspects as well as necessary legal requirements to operate – the company is on course to deliver 60 000 tpa of andalusite.

What is andalusite?

Andalusite, which is crystal-like in appearance, is a mineral with high alumina

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85% of all diseases in African children under five are caused by waterborne illnesses.

content; its refractory characteristics allow it to withstand high temperatures.

Did The mineral is mined and processed, then sold to refractory makers as a speciality mineral, particularly those in the steel industry. Quartz, graphite and other speciality minerals can also be extracted from andalusite and are used in various industrial applications of a technical nature, such as lithium ion batteries.

In 2001, Imerys Mining took a decision to expand its mining operations at Annesley mine in the Segorong area through its affiliate Rhino Minerals. The mine currently employs 120 people and has a

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on 27 March 2013 and simultaneously handed over new houses to 246 families who were relocated from Segorong to Praktiseer and Pidima, also in Burgersfort.

“The opening of the mine and the

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BELOW The Annesley mine employs about 120 people

 Diamonds & gems

“Imerys Mining is on course to deliver 60 000 tpa of andalusite.” Gilles Michel life-of-mine expectancy of 20 years. Because the planned expansion was going to have a direct impact on the land occupied by the Segorong community, it became necessary for Rhino Minerals to consult the affected community to consider resettlement, compensation and redevelopment of the community.

The resettlement, compensation and redevelopment has seen Rhino Minerals invest over R150 million for the relocation packages that were used for the building of the houses, compensation for grazing and livestock, and a cash settlement allowance for the relocating families.

Rhino Minerals has also formalised a Community Trust that is being used by the communities as a vehicle for community benefits, including acquisition of mining shares in the mining company.

“It is part of our culture to contribute meaningfully to surrounding communities where we operate through a variety of developmental projects. We take all our obligations seriously, including environmental and social issues, and are committed to running our operations safely and properly,” says Michel.

The project to build the houses was undertaken by construction giant Group Five. “Group Five Construction, represented by Group Five Housing, is proud to be associated with the relocation of villages and the construction of 239 houses varying in size from 51 m² to 180 m² at Praktiseer and Pidima in the Burgersfort area for the Imerys Group’s Rhino Minerals. We were also responsible for all services including water, sewer and the road infrastructure network; new electrical

ABOVE Imerys chief executive officer Gilles Michel addressed guests at the official opening of the mine and handing over of houses

infrastructure for both villages as well as the installation of high mast lights.

The successful completion of this quality project without a single lost time injury, ahead of programme and within budget, demonstrates once again that Group Five understands the needs of its mining clients and is positioned to deliver on their requirements,” says Group Five Housing’s contracts director, Peter Whalley.

A Group Five celebration Group Five congratulates the Imerys Group and Rhino Minerals on the opening of their Annesley Mine.

Group Five has a proud track record of delivery for our Mining Sector clients from off-mine village relocations to on-mine surface buildings and specific Mining Charter Accommodation and Mine Community Development solutions. Group Five is positioned to deliver on the Mining Sector’s unique requirements wherever their exploration may take them in Africa.

Group Five Housing Woodmead North Office Park, 54bMaxwell Drive, Woodmead Tel: +27 11 253 8700 | Fax: +27 11 656 1210 E-mail: g5h@groupfive.co.za

 Diamonds & gems

ZIMBABWE SHINE

Another diamond module Tenova Bateman Technologies Modular Plants has successfully completed the first stage of a contract to integrate and supply a second front end module for a diamond plant in Zimbabwe.

The aim of the project is to increase the ore processing capacity from the existing 200 tph to 400 tph.

T

he first-stage contract was signed in July 2012 and was completed within time and budget. The second-stage contract was signed in August 2012, and on completion will see the new module having sufficient capacity to process 400 tph through the ore-receiving bin and apron feeder. The 200 tph scrubber section, with a degrit module, will match the existing 200 tph scrubber and screening section. The scope also includes the in-plant conveyors, as well as modifications to the existing conveyors

and bins, to enable handling of the ore to and from both scrubber sections.

The first stage focused on the engineering study, detail design and procurement of long lead time equipment. The second stage involves procurement of the balance of equipment, fabrication, pre-erection and commissioning of the new module. Fabrication of equipment and structures has already started, with pre-erections currently in progress. The module was completed and exported to Zimbabwe at the end of March 2013. The modular

plants are self-contained or integrated into conventional plants. They are used for prospecting, exploration, research and testing, mining and mineral processing on land or sea.

The process design is robust and makes use of the best available components from reputable suppliers that support their products worldwide. Modular plants are easy to erect on-site since they are trial erected and pre-commissioned at the factory, where they are marked, stripped and packed into containers prior to dispatching to site.

Total Water and Effluent Treatment Solutions Unlock Potential, Create Value Innovative but proven solutions for domestic and industrial water and wastewater treatment, ranging from low-cost rural facilities to zero discharge and integrated industrial systems.

Tenova Bateman Technologies offers differentiated, project specific hydrometallurgical, mineral, water treatment and bio process technologies complimented by turnkey modular plant solutions.

58 Emerald Parkway Road, Greenstone Hill, Johannesburg, South Africa +27 11 899 9111 enquiries.TMM@za.tenovagroup.com www.tenovagroup.com

Tenova Mining & Minerals

 Diamonds & gems

MINOPEX

Diamond process professionals

Process plant operator Minopex has achieved resounding success in the diamond sector. It successfully operated Gem Diamonds Letšeng plant in Lesotho for 10 years, while also expanding into Botswana where the Lucara Diamonds Karowe project has delivered rare and large carats over the past six months, writes Laura Cornish.

M

34

inopex has been involved operationally in every diamond plant in the diamond-rich Lesotho. So much so that companies Minopex Lesotho and Minopex Botswana were established to best support all activities to the diamond plants we work on in these two countries,” says Rafael Abela, Minopex business development director. “The result of our drive to deliver and the commitment from our operational staff has seen our diamond operations staff headcount grow significantly over the

years. We currently employ over 300 people for our diamond operations alone.”

Radesh Sukhdeo, Minopex diamond operations director, admits that no project or operation is without its challenges. “In spite

Minopex values include:

Gem Diamonds

• Accountability – If it has to be done, I will do it • Integrity – I will do it beyond reproach • Focus – The client’s success is my business • Safety – paramount for all operations, never compromised.

“Letšeng’s location and associated climatic conditions pose the biggest operational challenge on-site, with temperatures varying constantly during the day, from -14 to 300C. Snow is a possibility all year round due to the altitude, which brings along

Inside Mining 05/2013

issues like pipes freezing and more brittle structural materials. The lack of country infrastructure is another major challenge influencing the procurement of process consumables and spares logistics.”

Minopex has recovered several large diamonds since the Letšeng plant was first commissioned in 2003 of this, Minopex has flourished and continues to deliver to clients’ expectations.”

Nonetheless, Minopex has recovered several large diamonds since the Letšeng plant was first commissioned in 2003. Such diamonds include the Lesotho Promise, Letšeng Legacy, Star of Lesotho and the Leseli La Letšeng.

Lucara Diamonds Looking at the Karowe project, it is the source of some of Minopex’s most recent

 Diamonds & gems LEFT One of the greatest operational challenges at Letšeng is the constant change in temperature and cold winter conditions RIGHT Minopex operates the Karowe DMS plant, which recently recovered a 239 carat diamond

successes. “It has been just over a year since the Karowe plant first became fully operational and already Minopex has surpassed the Karowe expectations in terms of contractual key performance indicators,” says Sukhdeo. Lucara has celebrated the recovery of a number of rare sky blue diamonds over the past six months and, more recently, a 239 carat stone.

Abela acknowledges that setting up a new company, Minopex Botswana, and operating in a new country (with its own legislation) was challenging. Further: “A new approach in Southern Africa in diamond recovery was adopted at the Karowe plant – using a SAG mill to liberate the diamonds from the host rock. This was the first milling exposure to Minopex in diamond processing. Given our experience in milling in general, however, we are able to operate and maintain this

mill comfortably.” The Minopex Operational Readiness Programme was also implemented to assist with plant ramp-up and to smooth the commencement of operations.

This programme requires Minopex to implement standard operating procedures across the spectrum of the operation and is adapted from country to country.

“That said, I can comfortably say that we have overcome our initial teething problems

and are now positioned to further expand our diamond business in the country,” Abela adds.

Abela explains that like Lucara Diamonds, more diamond miners are looking for technologies and operational procedures to improve their overall recoveries. Particular attention is being paid to diamond breakage and new technologies are being investigated, including SAG milling, X-ray sorting on

ď&#x201A;&#x201E; Diamonds & gems Partial view of the Karowe DMS plant

run-of-mine material as well as fully modular plants. â&#x20AC;&#x153;Even though Minopex has been processing diamonds for over 10 years and continues to gain first-hand experience in all aspects of processing diamonds, we work

demands, volatile commodity prices and depressive financial conditions. As a result, the rate of new projects implementation is decreasing.

Abela notes that while the company is pursuing a number of new diamond studies, it is also looking to diversify to secure growth targets in the Southern African region.

A new approach in Southern Africa in diamond recovery was adopted at the Karowe plant â&#x20AC;&#x201C; using a SAG mill to liberate the diamonds from the host rock closely with our clients and keep abreast of industry changes. Process optimisation projects are an ongoing element of our business.â&#x20AC;?

Growing the diamond business further Like all other mining-related businesses, Minopex is feeling the effects of a struggling industry. The mining sector is currently facing numerous challenges such as skills shortages, labour relationships, commodity

â&#x20AC;&#x153;Our vision is to â&#x20AC;&#x2DC;process the worldâ&#x20AC;&#x2122;. We want to be an operator of choice, which we achieved by creating long-term mutually beneficial partnerships as opposed to being just a service provider. The strong bonds formed between Minopex, Lucara Diamonds and Gem Diamonds is the perfect example of this and has set the foundation for a strong long-term collaboration going forward, which we aim to replicate with all our clients, current and new.â&#x20AC;?

PARTNER MAGAZINE NE

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CONTENTS

Water watch

Pg 38 The short-term intervention – Central Basin’s AMD treatment plant takes shape It’s a race against time. The combined efforts of the Trans-Caledon Tunnel Authority (TCTA), main construction contractor Group Five and all subcontractors must ensure the new treatment plant at the Central Basin’s South West Vertical Shaft is operational before acid mine drainage decants to surface.

Pg 52 Anglo ladies lead the water way Pg 44 Technical paper: Nanoscale materials deliver pollution remediation A carbon nanotube (CNT) integrated polymer composite membrane with a polyvinyl alcohol barrier layer has been prepared to separate oil from water for treatment of oilcontaining wastewater.

Pg 48 Salty solutions for process

water recycling The technologies implemented to help mines meet increasingly stringent water conservation regulations may have alleviated pollution in surrounding areas, but they have led to a different contamination challenge that needs managing.

Anglo American’s commitment to sustainable water development is being demonstrated through the key role that two female employees are playing in a groundbreaking water management programme.

Pg 54 MC Process takes dissolved air

flotation a step further MC Process’s constant attention to technological innovation and evolution has seen its new business unit, Scientific Water, make leaps and bounds into the wastewater sector.

Pg 58 Top treatment for mine

camp wastewater Treating mine camp wastewater may not be a core mining function, but it remains a core mining priority, especially in remote locations.

Pg 62 Gas detection – a water awakening Toxic and flammable gases pose a number of hazardous threats to water and wastewater industries. A combination of fixed and portable gas detectors should always be readily available on-site for a swift and effective response to a spill or leakage.

Pg 68 A new dewatering depot Pg 50 Tailings retreatment the AMD way A core part of the Mintails business is the management of AMD water that is used to reprocess tailings and recover land historically impacted by mining.

in Steelpoort Thanks to the rapidly growing demand for its products and services from the numerous mining operations in the area, Xylem Water Solutions South Africa will soon open a brand new rental depot in Steelpoort, Limpopo.

Inside Mining 05/2013

37

Water watch

THE SHORT-TERM INTERVENTION

Central Basin’s AMD treatment plant takes shape It’s a race against time. The combined efforts of the Trans-Caledon Tunnel Authority (TCTA), main construction contractor Group Five and all subcontractors must ensure the new treatment plant at the Central Basin’s South West Vertical Shaft is operational before acid mine drainage decants to surface writes Laura Cornish.

T

he acid mine drainage (AMD) dilemma, not a new concept to the South African public, reached emergency status when gold mining-acidic water started decanting from a defunct shaft in the Western Basin in 2002, polluting nearby spruits and groundwater. Today, the emergency is reaching critical status as government fights to prevent a repeat at the Central and Eastern Basins.

Every day the water level shared between the three Witwatersrand gold basins – Eastern, Central, Western – is rising at a rate of about 300 mm/d, according to the Department of Water Affairs’ (DWA) Inception Report published in March 2012. Pumping

38

Inside Mining 05/2013

stopped in the Western Basin in 1996, the Central Basin in 2008 and the Eastern Basin in 2011.

Fortunately, the crisis on the Western Basin has been curbed thanks to the upgrade of the existing Rand Uranium plant, which has been expanded from 12 Mℓ/d to 36 Mℓ/d.

This has stopped and neutralised the uncontrolled decant of water flows.

The severity of the situation has seen government take an active stance. In 2010, the government formed an inter-ministerial committee to evaluate technologies and methodologies to best solve the problem – for the immediate and the long-term future.

TCTA, a special purpose vehicle established

by the DWA, was appointed to implement the short-term intervention on its behalf.

The immediate priority: the Central Basin The Central Basin extends from Durban Roodepoort Deep (DRD) in the west to the East Rand Proprietary Mines (ERPM) in the east. The mine lease areas in this basin extend over about 251 km2.

Considering the amount of water necessary to treat the volume of AMD from the Central Basin is more than double that of the Western Basin, prevention (of AMD reaching the surface) is non-negotiable. Experts are predicting that water levels will reach the environment critical level around September/

Water watch October this year – only 186 m below the top of the shaft.

“If water rises above this level it could start having an impact on groundwater. The word ‘could’ is used as no one can accurately predict the hydrogeological reaction as the water level in the mine void rises,” explains TCTA business analyst Richard Holden.

Construction of a high-density sludge treatment plant and pump system at the Central Basin’s ERPM South Vertical Shaft near Germiston commenced in February this year and marks another major milestone in government’s fight to prevent AMD entering the Vaal river, which would ultimately cause a shortage of water to consumers in Gauteng and the surrounding provinces. “Without this project, the major impact will be on water security for anyone who draws water directly or indirectly from the Vaal River system,” Holden notes.

During the due diligence, various shafts were evaluated and given the cost to construct a new shaft, an existing defunct shaft was chosen. The plant will be situated at the existing South Vertical Shaft, which intersects the mining void of the Central Basin.

The eastern side of the Central Basin also represents the lowest pumping head.

For TCTA, allocation of sufficient funds to enable the construction contract to be awarded, coupled with obtaining environmental authorisation where legislation has never made provision for this type of project, have been significant challenges, Holden explains.

Regardless, the urgency of the project has necessitated TCTA bring its strengths to the table: funding and implementing large-scale water projects. “Thanks to much negotiation BELOW The ERPM shaft is barricaded and closed RIGHT The Ritz pump will be lowered into the shaft later this year

and compromise with ERPM, Central Rand Gold, the Department of Environmental Affairs, the DWA and all the interested and affected parties who participated in the scoping report, the success of this project will become a reality.”

Group Five Civil Engineering was appointed the full R319 million treatment plant construction contract, including civils, earthworks, building, and mechanical and electrical installation. It will be three times larger than the next biggest similar treatment plant in South Africa (at eMalahleni), with highly complex concrete structures, piping and electrical systems.

Holden says the plant is designed to treat 57 Mℓ/d. “At this stage the final ‘treated’ effluent will still have a high sulphate content (approximately 200 mg/ℓ). This is no different to what was discharged by the mines up until to 2008 when pumping and treatment at this site ceased. The stream bed is already heavily polluted from old tailings and urban stormwater run-off. Although this is not ideal, it is still a lot better than doing nothing until a long-term solution has been completed.”

The biggest impact caused as a result of the project is the increase to the salinity of the water in the Middle Vaal system, which necessitates the release of fresh water from the Vaal Dam to dilute it. “This will result in a deficit in the Upper Vaal system in 2015. What this means is that if there is a drought, water restrictions will need to be imposed.”

Wayne Poulsen, senior site agent for Group Five, explains the basic treatment process: “An extraction pump station, including two huge dewatering pumps, will pump acid water from the existing ERPM shaft. The water will be pumped to two reactors, which combined have an 80 x 80 m concrete footprint and are 5 m deep. Lime

dosed water iss pumped into the reactorr from the nt, which lime dosing plant, torage siincludes lime storage quipment los, dosing equipment ete tanks, and eight concrete each of which iss 16 m in diameter and 4 m high.

Two thickeners,, each 47 m in diameter, willl settle out Thee treated the solids. Th water will be discharged o the nearvia pipelines to uit and the

by Elsburg Spruit ed via pipesludge discharged sting ERPM line to an existing tailings facility.”” Group Five ponsible for is further responsible on and dethe construction cillary tanks livery of all ancillary and buildings as well as a atory. full-scale laboratory.

Ekurhuleni Metropolitan ill supply the Municipality will an water to necessary clean site and powerr will be proh-power 4 km vided via a high-power overhead line. uction time “Our construction frame is less than a year, meaning not a day can be ommissioning wasted. Trial commissioning vember 2013 , will start in November ations running with trial operations until 18 April 2014,” Howard ior contractss Wakefield, senior oup Five Civill director for Group ints out. “Wee Engineering points will hand the plant over to lete readiness TCTA at complete after which it must run per7. Our most manently, 24/7. ge throughout critical challenge ains time; we the project remains ur tight deadhave to meet our lines. But we are confident confident of success; we started well ng excellent and are making progress.” elieves that Wakefield believes ere were nueven though there merous tender bids put forward for the project, “our combination of pricing, technical abilityy and compliA’s stipulated ance with TCTA’s or enterprise requirements for nd BEE development and men(including uretorship, procurement, ment, employment,

Inside Mining 05/2013

39

Water watch

ABOVE Earthworks on-site is well under way

enterprise development and skills training) ranked us highest”.

Current project status Group Five's earthworks subcontractor Diesel Power is on-site. Earthwork construction on-site is well under way, says Chris Prinsloo, general manager of Diesel Power’s Civils & Bulk Earthworks Division. Primarily a mining contractor, Diesel Power is focused on growing the civils arm of its business.

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• 22 tip trucks Did • 1 TLB • 1 front end loader.

“This is such an exciting project to be involved with; to be part of a project saving the environment and preserving water resources for future generations is a great motivator,” Prinsloo states.

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The company is responsible for all project bulk earthworks, from excavation through to platform construction and backfilling.

Prinsloo admits that their challenge, like Group Five, is time. “It is a tight programme and we need to hand over the platforms so the next leg of the project can start.

We have also been experiencing a lot of rain.

Regardless, our commitment to the project is unwavering, and we will meet our deadlines.”

The company has eight staff members, 20 operators and 16 labourers dedicated to the job. “The reactor platform is already completed, the thickeners area is 70% complete, the dosing area is 60% complete and building platforms are 80% complete,” says Prinsloo.

“We have also just started on building the internal roads and the retaining walls.”

Plant on-site includes:

a te

Pumping – a key critical project element The scale and complexities of all the project elements are enormous, including the dewatering pumps. The mine shaft is over 1 500 m deep and the pumps, which are 15 m high (four storeys) and weigh 25 t, must be lowered 200 m down the shaft without being dropped.

Ritz Pumps South Africa, with its German joint venture partner Andritz Ritz, has been contracted to supply two heavy-duty mining dewatering pumps to the project. “They originally belonged to Central Rand Gold,

25 YEARS OF THE EXTRAORDINARY

TCTA is a state-owned liability management entity responsible for bulk raw water infrastructure development

The Trans-Caledon Tunnel Authority (TCTA) is proud to contribute towards a system which aims to deliver a sustainable water supply across Southern Africa.

planning, design and construction, place TCTA in the ideal position to facilitate development of bulk raw water infrastructure.

From an initial single project, TCTA now manages a portfolio of nine. These are the Lesotho Highlands Water Project Phase 1; the Berg Water Project (Western Cape); the Vaal River Eastern Subsystem Augmentation Project (Mpumalanga); the Mooi-Mgeni Transfer Scheme Phase 2 (KZN Midlands); the Olifants River Water Resource Development Project Phase 2 (Limpopo); the Mokolo-Crocodile (West) Water Augmentation Project (Limpopo); the Komati Water Scheme Augmentation Project (Mpumalanga) and, more recently, the Acid Mine Drainage Project (Gauteng) and the Metsi Bophelo Borehole Project (across six provinces).

TCTA is also expected to play a key role in the funding of the Lesotho Highlands Water Project Phase 2, the implementation of which was announced in a joint statement issued in August 2011 by the Governments of Lesotho and the Republic of South Africa.

The provision of water serves as a catalyst for sustainable economic development. The manner in which TCTA implements and manages its projects is governed by principles of transformation and sustainable development. We consider ourselves an instrument of social purpose, formed within society to accomplish social objectives. Consequetly, we are obliged to create new patterns, processes and strategies to tackle complex socio-ecological issues.

TCTA has committed itself to the progressive ideals and principles of sustainable development and their integration into various aspects of our business processes, giving us an opportunity to create value for all stakeholders, including social, economic and environmental facets.

All the above services are in support of governmentâ&#x20AC;&#x2122;s development agenda to make a better life for all. TCTA is committed to assisting government to achieve its socioeconomic objectives.

For more information on TCTA visit: www.tcta.co.za or call +2712 6831200

Water watch our ‘ZSM’ system, which can withstand in excess of 1 600 t Responsible government due to an axial non-positive department Department of Water Affairs and detachable pipe connecImplementing agent TCTA tion. Our technology enables Design Aecom us to free hang pumps up to Main contractor Group Five Civil Engineering Piping Murray & Dickson Construction 1 250 m with piping from Earthworks Diesel Power 80 to 600 nominal bore and Mechanical S.A.M.E achieve heads of 1 500 m.

Electrical Standard Electrical We can also insert a pump Civil foundations M3 Construction in large borehole from the Building and associated surface straight down into civil works Enza Construction the water source, suspend and hang the pump into the water and pump out directly without having to go through the shaft with a complex piping system as is required for the traditional underground high-pressure pump station setup.

“The use of single-suction submersible motor pumps which graciously donated them to TCTA for for pumping huge quantities or from great the project. The pumps are currently based at depths is associated with extreme loads on the Andritz facility in Germany and are due the unit,” Munnick continues. The higher the to undergo their second factory acceptance pump performance, the stronger the axial test. Following this, they will be shipped to thrust exerted on the pump, the motor and South Africa where we will oversee their inits thrust bearing. The consequences of this stallation,” says Chris Munnick, MD of Ritz are overloading and untimely shutdown. “The Pumps SA. solution is to double up, meaning greater du“The beauty of our system is that our pump rability. This is what our design is all about, is assembled above ground and then ‘free a double-suction pump that provides full hung’ – suspended from surface – which compensation for axial thrust. In short, the Key role players

Experts are predicting that water levels will reach the environment critical level around September/October this year – only 186 m below the top of the shaft means underground access to get to the pump station, as is generally the case in South Africa, is not needed,” says Munnick. “The pump is simply suspended in the shaft opening with

heavy-duty pump is designed for longer life – between 25 and 30 years.”

While the plant has been designed using historical information, final qualities will only

Critical facts Western Basin

Central Basin

Eastern Basin

Volume of AMD that needs to be treated

27 Mℓ/d

57 Mℓ/d

82 Mℓ/d

Environmental critical level (ECL)

1 550 m AMSL (165 m BCL)

1 467 m AMSL (186 m BCL)

1 280 m AMSL (290 m BCL)

Current level

0.88 m BCL

256 m BCL

423 m BCL

Breach of ECL if pumping does not commence

Breached already.

Sep/Oct 2013 Objective is to draw the water down to ECL

Location of treatment plant

Rand Uranium, Mogale South West Vertical Grootvlei No 3 Shaft, City Shaft, Germiston Springs

AMSL = above mean sea level

42

Inside Mining 05/2013

BCL = below collar level

Nov 2014

be known when pumping commences and the water level stabilises at and around the environment critical level, Holden points out.

“Projects such as this are extremely complicated and do not naturally fall into the category of national water resource, water board or municipal responsibility. They are a prime example of integrated water resource management and will shape projects to come as South Africa reaches the limit of its allocable water resources. They need time to come together to ensure that they are environmentally and financially sustainable,” Holden reiterates.

The next priority: The Eastern Basin The severity of the situation in the Eastern Basin is now critical and negotiations are already under way to secure access to land and infrastructure in the Grootvlei mining area. The property (excluding Shaft 4) is in liquidation along with its holding company, Pamodzi Gold.

Long-term strategy (source: the DWA website) Addressing AMD in the East, Central and West Rand underground mining basins is taking place through a phased approach and consideration regarding the implementation of a long-term sustainable solution is critical.

A feasibility study is currently under way to determine a sustainable long-term solution.

A consortium of consultants, led by Aurecon South Africa, was awarded the tender in December 2011 and the study commenced on 30 January 2012. The consortium is responsible for conducting this study under the strategic guidance of a study management committee, whose purpose is to ensure that the study meets its objectives.

Holden says that the long-term solution, specifically with regards to the Germiston AMD treatment plant, must ensure that the salts do not enter the Vaal River system.

One option is desalination – up to potable water standards.

There are five main focus areas that the study is addressing. These are: economics, technical, financial, legal and communication.

Economic focus The economic analysis will provide a detailed cost benefit analysis (CBA) looking at different scenarios relating to the handling of the AMD problem. The CBA must cover the different options such as the do-nothing scenario as well as an investment scenario. Furthermore, the CBA will examine the benefits and costs of allocating of responsibility for the scenarios to both the public and private sectors. The

Water watch

Financial focus It is anticipated that any solution to the problem will require massive investment. The financial analysis must inform the quantum of the investment. A financial model that takes

ow?

The technical work is being based on the available reports and is examining technological options that can be used to deal with the problem. One of the questions to be answered is whether a centralised facility or dispersed treatment facilities focusing on the different areas should be deployed.

The technical work also provides input into the financial model by considering the choice of technology, the availability, previous use and sustainability of technologies, as well as the life cycle cost implications. A preliminary design that takes all of the above into account will be prepared to guide government on possible solutions and on deciding on the optimal solution.

kn

Technical focus

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ch into account the full life cycle translated into a legally sound ate W costing of all the investments position to inform any agreeThe world’s rainiest required will be developed. ments to be negotiated. Leplace is Mount The financial model must gal inputs to any negotiation Wai’ale’ale in Kauai, incorporate scenarios of that may arise from discusHawaii. During an average year there are only 15 public and private sector insions between all the parties dry days. vestment as well as examining will also be provided. o the potential revenue sources, if y D i d Communication focus any, that can be derived from the Key stakeholders are engaged throughinvestment. Where possible, the actual out the study and measures are in place to costs and benefits as identified in the CBA effectively communicate study progress. will be included in the financial model. The It is expected that the feasibility study will study team will consider strategies for identibe followed by a formal Environmental fication, quantification and mitigation of risks Impact Assessment. that must affect the project and incorporate these in the financial model. u

economic analysis must provide a quantified set of cost and benefits which, wherever possible, can be fed into the financial model.

Study progress Legal focus The legal issues associated with the AMD are complex and multifaceted. As part of this study, the legislative issues associated with AMD will be studied and will contribute to the options selection as part of the CBA. The identification of legal risk, quantification of such risks as well as mitigation of such risks are an important part of the study. The risks that are identified will be

Phase 1 (the study initiation phase) is completed, while Phase 2 (the pre-feasibility phase) is in the process of being concluded.

Phase 3 (the feasibility phase) is the final phase of this study and has commenced.

The complexity of the study necessitated an extension of the study contract. The feasibility study is due for completion on 31 July and will, thus, have been conducted over an 18-month period.

Tel 0861 961 177 E-mail civils@dieselpower.co.za www.dieselpower.co.za

Diesel Power Civils and Bulk Earthworks is proud to be involved in the TCTA/ Acid Mine Drainage Project with Group Five.

We specialise in the following • Earthworks and lateral support for super basements • Design and construction of both public and private Roads • Erosion and stormwater control and infrastructure • River diversions and settling dams • Pipelines • Dragline Walkways • Incline Adits • Contract crushing and screening • Construction of HDPE and Concrete lined Slurry ponds • Construction of Stormwater control dams Diesel Power is a level 4 BEE contributor and has a 25.84% black shareholding.

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 Technical paper

NANOSCALE MATERIALS

Pollution remediation A carbon nanotube (CNT) integrated polymer composite membrane with a polyvinyl alcohol barrier layer has been prepared to separate oil from water for treatment of oilcontaining wastewater.

T

he CNTs were synthesised using chemical vapour deposition, and a phase inversion method was employed for the blending of the CNTs in the polymer composite solution for casting of the membrane. Relative to the baseline polymer, an increase of 119% in tensile strength, 77% in Young’s modulus and 258% in toughness is seen for a concentration of 7.5% CNTs in the polymer composite. The permeate through the membrane shows oil concentrations below the acceptable 10 mg/ℓ limit, with an excellent throughput and oil rejection of over 95%.

High volumes of wastewater in the form of oil-water emulsion are produced in various industries such as oil fields, petrochemical, metallurgical, pharmaceutical and others.

Oil concentrations in wastewater generated in the above industries range from 50 to 1 000 mg/ℓ; however, the acceptable discharge limit is only 10 to 15 mg/ℓ. Membrane filtration has been established as a widely used method for water purification, and various filtration techniques are differentiated by the minimum size of the suspended particles they can separate, namely microfiltration (0.1 to 10 mm), ultrafiltration (0.01 to 0.10 mm), nanofiltration (order of nanometres) and reverse osmosis, which can remove monoionic salts in solution. Microfiltration, ultrafiltration, nanofiltration and reverse osmosis have been successfully used in the separation of oil from water. These techniques are useful because of the high-quality water produced, simpler

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module design, low amount of chemicals used and low energy consumption compared to other treatment techniques. Although the aforementioned techniques are attractive, they are not without problems.

The two major problems with membrane filtration are fouling and concentration polarisation. Fouling is the accumulation of substances on the surface and/or inside the membrane pores, thereby decreasing the performance of the membrane.

Membrane fouling may occur due to the following reasons: (i) biological fouling, which is the growth of biological species on the membrane surface (ii) colloidal fouling, which leads to a loss of permeate flux through the membrane (iii) organic fouling due to the deposition of organic substances (iv) scaling, defined as the formation of mineral deposits precipitating from the feed stream to the membrane surface.

A total control of fouling is ideal to reduce the need for cleaning and enhance the permeate yield. When a mixture is in contact with the membrane, the components in the mixture permeate at different rates.

Concentration polarisation is when the components that permeate slowly, or not at all, accumulate and create a layer near the membrane surface.

Suitable modification of the membrane is probably the most sustainable approach to obtain fouling-resistant membranes. This would require the insertion of hydrophilic groups into a polymeric structure so that

Authors Selby Maphutha: School of Chemical and Metallurgical Engineering at the University of the Witwatersrand; DST/NRF Centre of Excellence in Strong Materials, Johannesburg Kapil Moothi: School of Chemical and Metallurgical Engineering at the University of the Witwatersrand; DST/NRF Centre of Excellence in Strong Materials, Johannesburg M Meyyappan: Center for Nanotechnology at the NASA Ames Research Center; Division of IT-Convergence Engineering at POSTECH, Pohang, South Korea Sunny E. Iyuke: School of Chemical and Metallurgical Engineering at the University of the Witwatersrand; DST/NRF Centre of Excellence in Strong Materials, Johannesburg the overall material becomes more hydrophilic and thus less prone to (organic) fouling. Poly(vinyl alcohol) (PVA), which is a water-soluble biodegradable polymer available with different degrees of hydrolysis, is an ideal candidate for this purpose due to its hydrophilicity and film forming characteristics. Commonly, membrane selectivity can be increased through the modification of the chemical structure of the polymer by cross-linking and grafting. Here we discuss the fabrication and testing of a carbon nanotube (CNT)-infused polymer composite membrane with PVA as a barrier layer, and demonstrate the effectiveness of the membrane in rejecting oil from wastewater. CNTs exhibit many desirable mechanical, thermal and other properties for a variety of applications. Several studies have shown successful transferring of thermal, electrical and mechanical properties of CNTs to polymer composites. PVA has been used as barrier

 Technical paper Fig 1 SEM image of a polysulfone (PSF) membrane (a) low and (b) high magnification without CNTs. BET analysis gives the average adsorption pore size as 18.9 nm

layer composite membrane to remove NaCl (22.8% rejection) and MgSO4 (83.8% rejection) from solution. Here, we seek to show that CNTs infused with a polymer composite membrane (using PVA as a barrier layer) are able to increase the mechanical strength of the membrane while still remaining highly effective for oil-water separation.

Results The CNTs used in this study were synthesised at 850°C using a previously described bulk production process and ranged between 500 and 1 000 nm in length. The concentric arrangement of the graphene sheets parallel to the tube axis, which is typical for a multi-walled tube structure, is confirmed in transmission electron microscopy (TEM) images presented in our previous publications.

The diameter distribution of the asproduced CNTs is uniform with diameters less than 100 nm observed. A close analysis of TEM images reveals representative multiwalled CNTs with inner diameters of 6.2

Fig 2 PSF membranes with 5% CNT (w/w) loading (a) low and (b) high magnification, PSF membranes with 10% CNT (w/w) loading (c) low and (d) high magnification. BET analysis gives the average adsorption pore size of 27.6 nm for 5% CNT loading and 31.8 nm for 10% CNT loading

to 7.9 nm and outer diameters of 26.2 to 32.1 nm. As the CNTs were not purified or subjected to acid treatment before utilisation, there was no introduction of any functional groups on the surface of the CNTs. Figure 1 shows scanning electron microscopy (SEM) images of the bottom (Polysulfone, PSF) layer of the membrane. This layer is highly porous with the visible pores being less than 10 microns. This particular layer contains no CNTs for comparison purposes.

Figure 2 shows the bottom (PSF) layer of the membrane with 5% and 10% CNTs in the polymer solution. The structure of this layer appears to change with the addition of CNTs. The pores in the membrane for the 10% CNT case appear to be more numerous and more

finely dispersed than at lower concentrations. BET (Brunauer-Emmett-Teller) analysis gives the average adsorption pore width as 18.9 nm at 0% CNT, 27.6 nm at 5% CNT and 31.8 nm at 10%. Figure 3 shows the PVA layer on top of the bottom (PSF) porous layer indicating no clearly visible pores on the SEM images.

Figure 4 shows the results from the tensile tests conducted on the fabricated

membranes. The Young’s modulus and toughness increase with CNT concentration first and then decrease after a threshold concentration (7.5% CNT:PSF) is reached. This drop in mechanical properties is due to the ready re-agglomeration of CNTs creating bundles at higher concentrations. Studies have shown that CNT bundles display diminished mechanical properties compared to a single CNT26.

Fig 3 SEM image of the polyvinyl alcohol (PVA) thin layer on base (PSF) membrane (a) low and (b) high magnification. No visible pores are seen due to the top layer of PVA being present

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 Technical paper

Fig 4 Plots of (a) Young’s modulus (MPa), (b) Toughness (J/cm3), (c) Ultimate tensile strength (MPa) and (d) Yield Stress (MPa) as a function of CNT loading in PSF. At a concentration of 7.5% CNTs in the polymer composite, there is a 119% increase in the ultimate tensile strength, 77% increase in the Young’s modulus, 258% increase in toughness and 79% increase in the yield strength. These increases are relative to 0% CNT loading

As such, it is important to obtain even distribution of unclustered CNTs across the matrix. The mechanical properties obtained in this study and displayed in Figure 4 and the corresponding error bars are comparable to results obtained from diverse processing techniques with variables such as degree of dispersion of CNTs, CNT concentrations in the polymer, various polymer matrices, etc., as all these parameters affect the mechanical properties. At 7.5% CNT concentration, there is a 119% increase in the ultimate tensile strength, 77% increase in the Young’s modulus and 258% increase in membrane toughness, all relative to 0% CNT concentration in the membrane. These values are quite favourable as there was no modification or purification of the CNTs used in the polymer solution. As-grown CNTs contain amorphous carbon and graphitic particles and it is possible to further improve the mechanical properties by using purified CNTs and other surface modification techniques.

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Discussion The rejection of oil by the membrane can be calculated using Equation 1:

where R is the rejection, and Cf and Cp are the feed and permeate concentrations, respectively. The flux through the membrane is determined using Equation 2:

addition of CNTs. The structure of the bottom layer in a thin film composite membrane has been shown to have an effect on the flux and the separation efficiency of the membrane.

Permeate concentrations below 10 mg/ℓ are achieved at 4 and 5 bar pressures by all the membranes, as seen in Figure 5.

Figure 6 shows the flux calculated using Equation 2 for different percentages of CNT loadings and pressures.

The flux through the membrane increases with an increase in pressure and CNT concentration. The flux achieved in this study is comparable to or higher than previously reported values. Similar to the impact on membrane separation efficiency, the CNTs alter the pore structure of the PSF layer allowing for greater flux across the membrane.

The SEM images (Figures 1 and 2) indicate an increase in pore diameter with an increase in the CNT concentration. The permeate flux can also be attributed to the PVA layer, which is hydrophilic. It has been found that hydrophilic membranes are more resistant to fouling and generally have a higher permeate flux. Cross-linking the PVA layer with dicarboxylic acid (maleic acid) has been shown to improve stability of the membrane. The intramolecular cross-linked molecules are smaller in size than the initial polymer molecules, with their size being dependent on the degree of cross linking. The results from Chunjin et al show that a PVA membrane has high values of oil retention and permeation flux, and the flux recovery ratio is more than 95%, which demonstrates that the PVA

where F is the flux, A is the effective membrane area and V is the volume of permeate through the membrane during time t. The rejection values of the membrane calculated using Equation 1 are given in Table 1 and Figure 5 shows the permeate concentration values. There is an increase of the oil concentration in the permeate and a decrease in the membrane rejection with an increase in pressure. As the transmembrane pressure increases, it rises above the capillary pressure of the membrane, which prevents the oil from en- Table 1 Rejection of oil by the CNT-polymer thin film membrane. tering the pores, leading Feed oil concentration is 287 mg/ℓ to it being forced through Pressure (bar) CNT loading (%) Rejection (%) the pores. There is also a 0 99.65 decrease in the membrane 4 4 5 98.61 rejection with an increase 97.39 4 10 in the CNT concentration 5 0 98.43 in the membrane. This is 5 97.56 5 expected as the structure 5 10 96.69 0 95.12 of the PSF layer is altered 6 5 90.59 6 by the membrane pores 87.11 6 10 growing larger, with the

 Technical paper Fig 5 The permeate concentration for different % CNT loading. There is an increase in permeate concentration with an increase in pressure and% CNT loading.

After 5 bar, the permeate concentration exceeds the lower limit of the allowable discharge concentration, which is 10 mg/ℓ

membrane has excellent anti-fouling characteristics to oil. The incorporation of CNTs into the membrane used in this study show that it is still feasible to have such high flux recovery ratio while also increasing membrane mechanical strength. Finally, though the oil/water mixtures tested here are artificial and oil-containing wastewater is known to have trace amount of surfactants, the results of this study are still meaningful and practical. Chakraborty et al suggest that additives in oily wastewater from plant operations will have an effect on the membrane performance. However, the oil particle size has a larger effect on the membrane performance relative to that by the additives in the oily wastewater. See table 1.

In summary, a CNT-polymer composite membrane with a polyvinyl alcohol barrier layer has been fabricated and tested for the separation of oil from water. At a concentration of 7.5% CNTs in the polymer composite, a 119% increase in the ultimate tensile strength, 77% increase in the Young’s modulus and 258% increase in the toughness were seen indicating the suitability of the membrane in practical applications.

Increasing the transmembrane pressure decreases the membrane separation but increases the flux. In the same way, increasing the CNT concentration in the membrane decreases rejection but increases membrane flux. Depending on the application of the membrane, a balance between the metrics such as rejection and flux can be obtained by varying CNT concentration in the membrane and pressure.

and characterised using a transmission electron microscope (TEM) (JOEL 100S).

A phase inversion method 17 was used to prepare the membranes in this study. A 10% (w/v) polysulfone (PSF) solution was prepared in dimethylformamide (DMF) under constant stirring. The solution was cast on a glass plate with the aid of a casting blade. The cast solution was left in ambient conditions for 10 seconds and thereafter fully immersed in distilled water for a period of 24 hours. A 1% (w/v) PVA solution was poured over the PSF membrane (which acts as the support) and kept in contact for three minutes after which the excess solution was drained off.

A 1% maleic acid (MA), which acts as the cross-linker solution, was poured on the PVA layer and kept in contact for 3 minutes (to allow enough time for cross-linking) after which it was drained off. The membrane was then heated in an oven at 125°C for 15 minutes. The structure of the membranes was characterised using a scanning electron microscope (SEM) (FEI FIB/SEMNova 600 Nanolab). BET analysis was conducted using the Tristar 3000 V6.05 A to obtain pore size information.

The CNTs were blended with the polymer solution in varying concentrations (from 0 to 10% w/v) before the solution was cast and immersed in water. The CNTs were dispersed with the aid of ultrasonic agitation in the membrane solution before casting. The mechanical tests on the membranes were carried out on the Hysitron Nanotensile 5000 Tester using thin rectangular (5 mm x 30 mm x 0.05 mm) samples of the membrane. The Young’s modulus, toughness, ultimate tensile strength and yield stress were obtained from the mechanical tests. For demonstration of oil-water separation, a reservoir was filled with distilled water (18 ℓ) and synthetic oil (50 mℓ). The reservoir was continuously stirred and heated to 35°C to facilitate mixing. The mixture was pumped through the membrane and flow readings were taken using a rotameter. The concentration of oil in water (after ultrasonication and continued stirring) was found to be ~287 mg/ℓ.

This paper has been edited for publication and citations have been removed. For references or information about the paper, please contact the editor at laura@3smedia.co.za.

Methods A vertically orientated continuous chemical vapour deposition (CVD) reactor was used to produce CNTs at 850°C as outlined in our previous studies using ferrocene, which acts as both the catalyst and carbon source. About 4 g of ferrocene was placed inside the vapouriser and the vapour was carried to the reactor by argon carrier gas. The solid carbon product of CNTs was collected from the cyclone Fig 6 The flux through the membrane at different pressures and % CNT loading. The increase in flux is due to the increase in % CNT loading, which alters the membrane structure as can be seen in Figures 1 and 2

Inside Mining 05/2013

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Water watch

PROCESS WATER RECYCLING

Salty solutions sink in The technologies implemented to help mines meet increasingly stringent water conservation regulations may have alleviated pollution in surrounding areas, but they have led to a different contamination challenge that needs managing, writes Laura Cornish.

M

ining operations’ water usage and processes have evolved considerably over the past two decades. While it was common practice to use and consume clean water for all activities on-site with little thought given for downstream water pollution discharge impacts, such methodologies today are prohibited.

“The 1990s saw new trends emerge aimed at reusing different qualities of water in various elements within a closed mining circuit, recycling water and reducing wastewater discharge. Capturing and reusing water within the plant process has evolved to become common practice today – placing less stress on the environment and reducing municipal clean water consumption. Despite this, the necessity Monitoring stream flows as input to hydrological baseline studies

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for water balance modelling and managing the distribution of water within a mine has and continues to play a more important role within an operations life cycle now than ever before,” SRK partner and principal hydrologist Peter Shepherd points out.

An evolving challenge “The downside to process water recycling is the significant rise in salt levels if the water is not diluted with clean water at regular intervals,” Shepherd explains.

While salt is not considered a toxic substance, it can cause major environmental and process dilemmas. Water recycled over a 20-year period raises salt levels substantially; in some instances, SRK has measured the total dissolved salt (TDS) levels in process water dams of greater than 8 000 mg/ℓ.

“To put it in perspective, the maximum allowable drinking water (Class II –SANS 241 2006) is 2400 mg/ℓ,” Shepherd notes.

Acid mine drainage (AMD) in South Africa’s mature coalfields.

Shepherd acknowledges that while South Africa’s gold AMD crisis is being addressed and solutions implemented, other sources of AMD should be evaluated and prevention measures planned for.

South Africa’s primary Emalahleni coal fields will ramp down over the next 20 to 50 years as the new Waterberg coalfield region develops, leaving a host of defunct underground and opencast mines, as well as waste facilities. “The coal mining industry needs to come together and understand the entire coal basin as a unit to ensure that the environment is preserved when mining ends, and underground water levels are maintained at a stable level,” Shepherd mentions.

Rehabilitation of these old mining areas needs to be done in such a way that surface water does not unnecessarily impact the groundwater.

Water watch

“Water with high concentrations of salts is unpleasant tasting and the long-term use may pose a health threat to consumers.”

Salt balances developed for the Rustenburg area have seen the TDS increase from about 1 000 to about 4 000 mg/ℓ – a result largely caused by the mines’ efforts to reuse as much water as possible. Certain mines in the area have already started budgeting for steel infrastructure replacement as a result of the corrosion water with elevated TDS can cause.

Steadily increasing salt levels means that eventually the water will need to be treated.

“The impact of discharging high TDS level water into the environment is significantly more severe than less salty water but the environment is only one factor that mining houses need to consider. The impact of recycled water with a high TDS concentration can drastically affect mining process circuits as well.

Plants are designed for a certain minimum water quality and will not operate optimally if salt levels rise beyond a certain point.

High salt levels will also corrode most metal components in a circuit, raising operational and replacement costs.

The solution Shepherd says that treating water with a high TDS concentration is an option, but

should be the last resort as the extra capital and running costs of treating heavy salt water will only add further to a mine’s overall costs – unnecessarily.

“There are alternative, cost-effective, rational methods to combat this issue. Split-

Graphic – Stormwater control on mines

Fortunately, because water has become such an essential operational component, mines are embracing this challenge and ac-

“The downside to process water recycling is the significant rise in salt levels if the water is not diluted with clean water at regular intervals.” Peter Shepherd, partner and principal hydrologist, SRK Consulting

ting types of water use based on process requirements and utilising the right qualities for the right processes will enable mines to treat less water – and only the most highly polluted,” Shepherd outlines.

This will further enable mines to stop using their stormwater dams for process water storage, which pose further environmental hazards should they overflow.

Considering higher rainfall is predicted to substantially increase the amount of contaminated water a mine spills into the environment, the list of reasons to revise water reuse strategies is endless.

knowledging the need to adapt their processes accordingly, Shepherd declares. And many are turning to Shepherd, his team and SRK to find solutions to what could soon become a significant mining problem.

Water balance development is a core strength and strategic business focus for consulting engineers and scientists SRK. The company employs a range of tools to monitor and control salt levels in mine water, from a simple spreadsheet-based method that mines can employ without specialist skills to purpose-designed computer models that are more complex.

Inside Mining 05/2013

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Water watch

TAILINGS RETREATMENT

The AMD way The acid mine drainage (AMD) issue dominating South Africa is underpinned by a narrative of blame-seeking. This has stifled the technical debate about solution implementation to the detriment of the regional economy.

A

SX-listed tailings retreatment company Mintails believes it is better to refocus attention onto the technical aspects of solution implementation in partnership with government to solve AMD challenges.

A consensus is emerging that a solution is possible, under government leadership, phased to mitigate the risks specific to each basin. This consensus suggests that the immediate intervention should be to neutralise the AMD by means of a high-density sludge (HDS) process, with a possible long-term solution being desalination to augment strategic water supplies in Gauteng.

Mintails is fully supportive of this emerging trend and has committed itself to the UN call to make 2013 the International Year of Water Cooperation, specifically for the protection of groundwater resources, through enhanced governance structures created in partnership between the public and private sectors. To this end, Mintails has developed a patented treatment process that has been offered to the state for consideration as one of the options for the immediate intervention in the Western Basin. This process is fully compatible with any future decision to desalinate.

Mintails is a mining closure company that reprocesses tailings dams as part of a comprehensive MRA remediation process aimed at ultimately returning legacy mining impacted land to higher social and economic use. A core part of that process is the management of acidic water.

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AMD water is abstracted from the void and then treated by the on-site facilities to a level where it can be used for process water. This is used to hydraulically mine the tailings dams located in the upper reaches of the Wonderfontein Spruit, an ecosystem highly impacted by more than a century of deep-level mining of both gold and uranium. The recovered tailings are then processed at the metallurgical plant to extract residual gold before the slurry is returned to a final dump as waste. But this slurry can also be used to neutralise AMD in significant volumes.

Test work conducted by the company has shown that in the Western Basin, around 40 Mℓ/d can be neutralised to a quality acceptable to the regulatory authority for use as grey water, or as feedstock into future desalination plants. Many benefits arise from this process, making it a valuable contribution to the overall AMD management strategy being developed by the government.

The immediate benefit is that it can be rapidly implemented in the Western Basin without disrupting any long-term planning regarding the future potential of a desalination plant augmenting supply into the economic heartland of Gauteng.

Another benefit is that the HDS process, with its costly sludge handling and management requirements, is done away with.

R&D, confirmed by independent laboratory evaluation, indicates that the sludge generated from the neutralisation of AMD by exposure to barren tailings is seeded onto

A core part of the Mintails business is the management of AMD water that is used to reprocess tailings and recover land historically impacted by mining

the individual tailings particle in a powerful bond that is more chemically stable than HDS on its own. Furthermore, the hydrophilic nature of the precipitate so generated changes the hydrological parameters of the tailings in a way that reduces the rate of transmission of acidic rainwater through the tailings pile. This is a benefit as it reduces future acid generation capacity triggered by acid rain. This implies that the consolidated barren tailings need to be rehabilitated to reduce the ingress of acid rain.

The main benefit accrues to the taxpaying public, because the overall cost of such a process is considerably lower than the conventional HDS technology in mainstream use.

Mintails is proud to be a responsible mining closure company operating in the challenging environment created by a legacy of mining that has given rise to the problem we face today. Through this process, Mintails and other mining companies can consolidate the many scattered tailings dams in a safe way to release rehabilitated land back into the regional economy. Through the process of responsible closure, Mintails believes that the many challenges of the heavily impacted legacy mining areas in which it operates can be rehabilitated for better social and economic use.

Water watch

FEMALE FORCE

Anglo ladies lead the water way Anglo American’s commitment to sustainable water development is currently being demonstrated through the key role that two female employees are playing in a groundbreaking water management programme that is reaffirming the company’s vision to be a leader in mine water management.

D

r Johanita Kotze is currently heading up the implementation of Anglo American Technical Solutions’ Integrated Water Management Service (IWMS) for the company’s global operations. Janet Smith is conducting research into more effective reuse of water.

The IWMS is focused on assisting Anglo American’s operations and projects to effectively, efficiently and sustainably implement the company’s water strategy. It proposes a step-by-step approach of sifting through the extensive data and issues flagged in both external and internal mine-water reviews and audits, identifying the priority issues and implementing best practice solutions to those.

The initial phase of the IWMS – identifying key priorities at two sites – is expected to be completed by the end of 2013.

Smith is a senior chemist at Technical Solutions’ Research Unit, where she researches more effective reuse of water, specialising in water management and solid/ liquid separation, primarily in the area of thickener optimisation.

Smith is co-author of a technical paper titled Design and development of a novel thickener feedwell using computational fluid dynamics.

The benefit of this research relating to the thickener feedwell technology shows that effective thickener performance allows achievement of maximum underflow solids and overflow clarity for a given purpose.

Better quality thickener overflow water can be reused for plant processes, making water available for rapid recovery and reuse with minimal losses and energy requirements.

As part of the company’s ongoing water programmes, Smith is now also involved in an AMIRA Project (AMIRA 1087), which is focused on integrated tailings management.

AMIRA is a global, independent association of minerals companies that develops, brokers and facilitates collaborative research projects. As a participating

Boipuso Semenya takes a pH reading at a groundwater abstraction borehole near RBMR (Rustenburg Base Metals Refiners) in Rustenburg (January 2012) Photographer: Geoff Brown

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Water watch

Dr Johanita Kotze

Vinesh Dilsook monitoring the inflow of treated water at the Klipgat return water dam - Rustenburg

company, Anglo American is one of the funders, contributors and beneficiaries of AMIRA projects.

Kotze is principal hydrogeologist in the Technical Solutions’ Consulting Unit, and heads up the implementation of an integrated water service for Anglo American’s global operations. She is the driving force behind IWMS and is one of only a few hydrogeologists

worldwide who posses the particular qualifications and experience she has.

The Technical Solutions team is part of the company’s multidisciplinary mining and technology function, which is focused on water management.

Research into more effective reuse of water is only one of the many initiatives currently under way at Anglo American in support of the company’s water strategy and vision. The company is cognisant of both the environmental and profit value of increased efficiency in water use in its operations.

Richard Garner, the water manager for Anglo American, believes that Smith and Kotze’s work has proved critical to the real difference that the company is achieving in terms of waJanet Smith ter sustainability.

“With the current water stresses being experienced around the globe, effective water management and research is of paramount importance. Anglo American is therefore delighted in the results being achieved by the IWMS team, and in particular the role being played by Smith and Kotze in furthering our water strategy.

“Through their innovative research and implemented techniques, they are ultimately helping to ensure that our company can plan and implement totally integrated water initiatives that will maximise water recovery and ensure sustainability to meet current and future water needs,” concludes Garner.

Water watch

DISSOLVED AIR FLOTATION

MC Process goes a step further Minerals processing equipment will always be MC Process’s core business. Its constant attention to technological innovation and evolution, however, has seen its new business unit, Scientific Water, make leaps and bounds into the wastewater sector, writes Laura Cornish.

D

espite the major successes achieved through its conventional minerals processing equipment ranges, MC Process CEO Mark Craddock’s current focus for growth lies in the water sector – for all types of wastewater, including sewage and effluent treatment using dissolved air flotation (DAF) and reverse osmosis technologies. In line with its vision to become a substantial player in the water sector, the company has launched a water-focused division called Scientific Water, which as its name suggests, evaluates and provides cost-effective, alternative technological/scientific approaches to wastewater treatment.

Not only has the company successfully reintroduced the concept of DAF to the mining sector, but will soon complete research and development that showcases how the addition of electrocoagulation can reduce the running costs required to treat wastewater (such as acid mine drainage), particularly in the coal sector.

DAF is an effective process for effluent and wastewater clarification. It works by producing a stream of micro bubbles that

attach to solids, which float to the surface and are removed by a scraper system. DAF units are especially effective when incorporated into a wastewater treatment system.

Following on from the success of the DAF process, Craddock has been investigating methods to enhance the treatment of coal-associated acid mine water further,

water’s pH) step into the process. “By introducing this step prior to DAF, I believe the amount of lime required for neutralisation decreases significantly,” Craddock explains.

“Lime is a necessary but significant operational cost in this process, which in mining terms is a frustration as it does not contribute directly to production profits. Our test

In line with its vision to become a substantial player in the water sector, the company has launched a water-focused division called Scientific Water with a particular focus on reducing operational costs.

Coal washing plants use lime to neutralise acidic waste or process water as a starting point for recirculation and reuse. A DAF unit is then able to effectively separate the solids from the water. In collaboration with major coal role players such as Anglo American Thermal Coal, Craddock is currently investigating the potential of incorporating an electrocoagulation (which raises the

work thus so far is indicating that this process is an effective wastewater treatment method that ably works with much lower volumes of lime,” he continues. In conjunction with DAF, overall costs are kept to a minimum. It is already common knowledge that this technology on its own is significantly cheaper than traditional methods.

Speaking of the industry’s acid mine drainage problem in general, Craddock says that thanks to technologies such as DAF, the situation is not a crisis, but a “solution problem”.

Introducing a new DAF concept to the market is not the ‘end of the road’ for Craddock. “We are further investigating possible commercial opportunities available for the floated metals recovered from the DAF process.”

The foundations and success MC Process celebrates today, only five years since it was first registered, is built on R&D. “It remains a key constituent of our business.” In line with this business strategy, the company continues to invest heavily in its extensive LEFT Dissolved air flotation is an effective process for effluent and wastewater clarification RIGHT A dissolved air flotation unit

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Water ate watch atc laboratory pilot-scale testing equipment uipment and facilities.

Through Scientific Water, MC Pro-cess recently installed and commissioned two new DAF units at Anglo American Thermal Coal’s New Vaal colliery in Vanderbijlpark, where the units are ensuring that the treated water being discharged is not impacting on the environment.

Last year, the company also secured the contract to supply t, toan entire sewerage treatment plant, tem and gether with a reverse osmosis system ackaged acid mine drainage treatment packaged ng’s new plant (with DAF) for Ikwezi Mining’s wcastle.

Ntendeka coal operation near Newcastle. t ll ti Equipment procurement and installation has commenced following the company’s recent water licence grant,” Craddock reveals.

Additional minerals processing equipment ranges Outside of water, Craddock speaks enthusiastically of some new technologies and equipment ranges the company has introduced over the last year.

MC Process is offering a complete package gold elution plant, which uses an extraction technique aimed at recovering gold that has been liberated into a cyanide solution as part of the gold cyanidation process. Gold in solution is loaded onto activated carbon, which is then sent through a series of steps in the elution process. Gold is then electrowon from eluate and smelted to yield gold bullion.

“We have also established an exclusive partnership with Elgin Equipment Group, from the US, a worldwide leader in the design,

manufacture and service of coal processing and industrial equipment; we represent Centrifugal Services CSI - rotary breakers, tabor screens and Centrifugal Mechanical Industries’ CMI centrifuges, which we now have the African distribution rights to,” Craddock adds.

The company’s broad array of products and services includes new and rebuilt centrifuges through its company’s Centrifugal & Mechanical Industries and CSI Technologies companies.

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Process Equipment that Work MINERAL PROCESSING Agitators Attrition Scrubber Antimony Plants Clay Breaking Systems CMI - Centrifuges Counter Current Decantation (CCD) CSI - Rotary Breakers Electrowining (EW) Flotation Cells Flocculant Plants Gold Elution High Energy Conditioners High Density Thickeners High Rate Thickeners Ion Exchange Iron Precipitation Plants Lamella Thickeners Leaching - Accelerated, VAT & Pressure Lime Plants Paste Thickeners Pilot Plants & Laboratory Scale Equipment Packed Bed Clarifiers Reagent Make-up & Dosing Plants Solvent Extraction (SX) Thickeners QVA - Cyclone QVA - Log Washers QVA - Multi Spigot Hydrosizers QVA - Teetered Bed Separator (TBS)

WATER TREATMENT Chemical Treatment Clarifiers Dissolved Air Flotation (DAF) Electrocoagulation Electrodialysis Froth Removal & Auto Dilution (FRAD) Ion Exchange Microfiltration Mixers Multi Media Filters Nanofiltration Reverse Osmosis (RO) Ultrafiltration ENGINEERING SERVICES Draughting Equipment Upgrading Laboratory Testwork Process Optimization

Telephone: +27 (0) 11 432-2195 Email: info@mcprocess.co.za Website: www.mcprocess.co.za

MONITORING

The beginning and end of water preservation Africa suffers from water shortages and will continue to do so in the future. As a result, it is essential that the water used and returned to the environment by the mining industry is of a superior quality.

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ince its establishment in 2006, Quadrex Technologies has been supplying quality control and monitoring equipment aimed at evaluating waste products from the manufacturing process – in particular wastewater. “The equipment we supply delivers necessary data to the relevant industry personnel, ensuring that they know the quality of the water they have used and will eventually be returning to the environment, enabling them to take the necessary clean up steps if required,” explains the managing member of Quadrex Technologies SA, Guido Mol. “In the mining industry, where a lot of water is used during the extraction process of minerals, our products find their way into QC laboratories, on-line water quality control monitoring processes as well as final wastewater analysis (prior to discharging it). Our equipment is accurate and can detect very low concentrations of heavy minerals and other pollutants and nutrients; it is also sensitive, portable and on-line,” he continues.

Numerous studies have indicated the need to know the general conditions of industrial effluent, including the content and concentration of heavy elements or any other pollutant in wastewater, prior to discharging it into streams, rivers, dams, lake, etc. If unchecked, this can have disastrous results for any living form in or close to the polluted water source.

The rising acid water table in the Gauteng region, for example, is raising concerns regarding water pollution of boreholes, rivers, dams, lakes and other surface water. “The equipment we provide has sensitivities that will easily meet or beat the current environmental legislation requirements in any industry.”

Various measurements can be performed with the respective type of equipment in an on-line monitoring, in-field or on-site laboratory environment. “Our equipment caters to all heavy metals, including aluminium, arsenic, beryllium, cadmium, chromium, copper, gold, ion, mercury, manganese, nickel, lead, tin and zinc, as well as general water conditions including temperature, pH, turbidity, conductivity, resistivity salinity, etc.,” says Mol. “While many Quadrex-similar systems are available, we believe that we provide equipment that caters to and is particularly suited to the mining industry, which has to deal with heavy element pollution and other forms of contamination. The increasing numbers in worldwide installations and usage of our equipment is a sign that customers are realising their moral and ethical obligations to protect water resources.”

ONLINE WATER MONITORING ANALYSIS EQUIPMENT Applications include: River water, Drinking water treatment plants, Sewage treatment plants and Industrial effluents, including food, car, dairy, petrochemical and paper mill industries, as well as power plants Available parameters: - Online nitrate - Online-UV COD - Online dual nitrate/UV COD - Online ammonium - Online sulphide - Online chlorophyll-a, fluorescein, rhodamine and oil in water - Online UV COD in-situ probe - Online phosphate - Online hexavalent Cr - Multi-parameter e.g pH, conductivity, redox, DO, TSS, temperature - Metals like Ni, Zn, Fe, Cu, etc.

PORTABLE AND LABORATORY HEAVY ELEMENT ANALYSIS EQUIPMENT Portable field-kit and benchtop Metalyser systems for precise analysis (to ppb levels) of heavy elements in water and soils.

Depending on the models, the following elements are measurable: Al, As, B, Bi, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sn and Zn

PORTABLE WATER ANALYSER The innovative design allows for easy handling and field deployment by a single user.

In its standard configuration, the WIZ probe detects trace levels of the main four nutrients compounds: • ammonia (N-NH) • orthophosphate (P-PO3) • nitrate + nitrite N-(NO) • nitrite (N-NO234+NO2).

WIZ probe automatically manages the well-known spectrophotometric wet chemistries and an advanced fluorimetric method for ammonia measurement.

Contact: Guido Mol Mobile: +27 083 629 2625 • Fax: 086 672 2805 Tel Office: +27 (0)11 882 5051 • E-mail: gdjm@mweb.co.za

www.quadrex-technologies.co.za

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MINE CAMP WASTEWATER

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Treating mine camp wastewater may not be a core mining function, but it remains a core mining priority, especially in remote locations.

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astewater treatment specialist Veolia Water Solutions & Technologies South Africa, through its subsidiary VWS Envig Botswana, is ensuring that mining companies focus only on their core business, leaving the ‘dirty work’ to it.

Two of Botswana’s largest copper mining companies recently contracted VWS Envig Botswana to supply containerised wastewater treatment plants to improve the quality of discharge water coming from mine camps.

“A copper mining project in northwestern Botswana has already received its new 90 m3/d trickling filter treatment plant, which we delivered in December,” says Wayne Taljaard, general manager at Veolia’s Engineered Systems & Services.

“The entire solution was designed to be upgraded to 180 m3/d and we have manufactured the second containerised plant at our factory in Isando and delivered it.”

Together, the plants will treat domestic Veolia’s modular water treatment plants address small-scale water problems in shorter time frames, which has resulted in increased popularity among mine camps throughout subSaharan Africa

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Inside Mining 05/2013

sewage generated by nearly 900 people to within legislated discharge standards before being released into surface water streams.

A second copper mining company, a long-standing Veolia customer, has commissioned a 75 m3/d trickling filter wastewater treatment plant to upgrade sewage generated by roughly 350 residents at its mine camp in north-eastern Botswana.

“This trickling filter plant, along with all ancillary equipment, was completely containerised and delivered in March 2013.

The customer opted to construct a separate septic tank, which means both modular and civil construction principles were used to build this plant – what we call a hybrid installation,” Taljaard explains.

Typically, Veolia will include the septic tank within a standard 12 m container, which allows the entire plant to be transported via road to remote locations. Containers are corrosion protected and completely

watertight, and with minimal moving parts that need maintenance, they are ideally suited for operation in remote African settlements. “Once installed, they are remote monitored and only need an operator to do a daily inspection, making them incredibly cost effective to run,” Taljaard continues.

Water industry growth in Botswana VWS Envig Botswana is growing significantly in the semi-arid country’s water market and was recently awarded a contract to design, supply and commission a 6 000 m3/d potable water plant in Maun, northern Botswana. The plant, located near the banks of the Thamalakane River, is scheduled to be commissioned in September 2013 and will be operated and maintained by Veolia for a subsequent sixmonth period.

Previous Veolia installations in the country include a large-scale reverse osmosis plant for a diamond mine near Francistown, as well as a large-scale demineralisation plant at a high-capacity power plant.

Water watch

KIBALI

A waterproof water warranty SBS Water Systems is supplying two of its newly launched ‘Proudly South African’ SBS Tanks to one of the largest undeveloped gold deposits in Africa – Kibali – proving that this company and its reservoir products are taking their place in some of the continent’s largest mining applications.

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he Kibali project is Randgold Resources’ latest venture (together with AngloGold Ashanti) and remains on track to start producing at the end of 2013 and reach full production the year after. With a 10 Moz mineral reserve (and 18 Moz resource), the project represents one of the largest undeveloped gold deposits in Africa. It is set to deliver an average of 600 000 ozpa for the first 11 years with an average grade of 4.2 g/t.

The project has a 17-year lifespan, although ongoing exploration is expected to see this extend substantially.

Situated in the Democratic Republic of the Congo, Kibali’s 6 Mtpa run-of-mine throughput is enormous.

The Kibabli site is well into construction

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technology and high-quality materials, SBS Tanks have a range of standard and special fittings Did available to meet many industrial and engineering requirements. The wall panels and roof sheets are made of hot-dipped steel, coated with a molten alloy, making them highly resistant to corrosion. The tanks carry a 10-year non-leak warranty and ongoing manufacturer support, but have an estimated life span of more than 60 years under normal climate and operational conditions.

While SBS is heavily invested and focused on acquiring more equipment orders from Africa, the company is aware of the challenges such project work brings. “In the case of Kibali, the area is a malaria zone, meaning all our installers have to be prepared and vaccinated accordingly.”

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SBS Water Systems was contracted to supply two SBS Tanks to the project: a 588 000 ℓ tank to store mine service water and a 98 000 ℓ tank for potable water storage. They are currently on-route (by ship) to site and are expected to arrive shortly.

It will take only four qualified installation workers and site managers 12 days to erect the tanks on-site.

“We make a point of sourcing local raw materials from suppliers in the Durban area, resulting in prompt delivery,” says SBS’s MD, Delayne Gray. “We are further able to make rapid improvements and respond quickly to any crises that may occur either during installation or after.”

SBS Tanks are made out of premium quality zincalume panels with internal liners ranging from 12 kℓ to a staggering 3.3 Mℓ, measuring 21 m in diameter and 9 m high. “We are also gearing our operations for ISO 9001 accreditation, which we expect to achieve by the end of this year,” Gray adds.

Designed by leading structural engineers and manufactured using proven

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Packaging of the parts for the Kibali tanks for shipping

Water watch

GAS DETECTION

A water awakening Toxic and flammable gases pose hazardous threats to mine water. A combination of fixed and portable gas detectors should always be readily available on-site for an effective response to a spill or leakage, says Robbie Taitz, marketing manager for gas detection products at MSA’s African division.

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arious gases, some highly common and others extremely rare, are present throughout the processing and treatment stages in both water and wastewater applications. Due to the fact that each gas is inherently different, it is of the utmost importance that fixed and portable gas detectors are strategically located or worn in key areas that are exposed to these gases. This is not only for monitoring purposes, but to save lives.

These gases are plentiful and include, but are not limited to, methane, oxygen, hydrogen sulphide, chlorine, carbon monoxide, carbon dioxide, sulphur dioxide, ammonia and ozone. In wastewater applications, these gases originate from many sources, such as sewers, pumping stations, aeration tanks, sludge digester tanks, deodorising plants and treatment plants. In potable water applications, the gases originate from

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locations such as gas storage areas, gas dosing plants and ozone generators.

In addition to being precisely accurate with readings, both portable and fixed gas detectors should also be highly robust and durable in order to withstand exposure to the harsh operating conditions that occur in a water plant, including high impact, corrosion and, of course, water damage. Bearing these factors in mind, quality should take preference over price.

Mining wastewater (photograph credit to Bloomberg)

By miniaturising the sensors’ controlling electronics and placing them inside the sensor itself, MSA XCell sensors are able to offer superior stability, accuracy and repeatability. The sensors are a breakthrough in chemical and mechanical sensor design, enabling faster response and span calibration times.

For fixed gas detection solutions, the MSA Trigard Monitoring System is designed to monitor chlorine, sulphur dioxide and other toxic gases, combustible gases, as well as MSA solutions oxygen deficiency or enrichFor personal protection purposment. These new monitors ofes, the MSA Altair 5X Multigas fer an affordable monitoring Detector detects flammable solution for a variety of needs gases, oxygen and toxic gasand were designed specifically es and is a tough and functional for water and wastewater facilioption for the water and ties, which are typically large wastewater industry. producers of these gases. An MSA Trigard MSA is a global leader in advanced feature of this dethe development, manufacture and supply tector includes MSA’s patented sensor disof sophisticated products that protect peoconnect under power feature, which allows ple’s health and safety. for sensor change-out without declassifying A rugged polycarbonate housing provides a hazardous area. Additional advantages of unsurpassed durability, including the abilithe MSA Trigard monitoring system include ty to survive a 10-foot drop. Inside, a field interchangeable smart sensors and a stateproven integral pump provides consistent of-the-art LED display. gas flow without the problems of externalFinding the balance between cost savings ly attached components. Ergonomic design, and optimal safety is one of the biggest chalglove friendly buttons and a high-contrast lenges facing all industries in the current display make the Altair 5X easy to use in global economic climate. It goes without all applications. saying that worker safety should never be The real strength of the multigas detector, compromised for cost savings. however, comes from new sensor technoloInvesting in higher quality equipment gy. MSA XCell sensors have a typical life of that is initially more expensive during the more than double the industry average and purchasing phase not only ensures a higher are engineered using MSA’s proprietary apdegree of employee safety, it actually saves plication-specific integrated circuit design. on overall long-term costs, due to greater reliability, performance and far superior product warranties.

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Water watch

DRIVING DRAINAGE

Samancor’s high-tech tailings

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was inserted on top of the Zipcore sheeting.

Two-meter wide ZipCore Pro N – a highstrength, robust, preformed drainage system consisting of a horizontally aligned, single cuspated, high-density polyethylene sheet – was laid down on the prepared area.

The Zipcore acts as an impermeable barrier, directing the entrapped water flow to the spinal 150 mm deep Megaflo panel drain comprising a high-strength slotted HDPE core completely wrapped in a bidim geotextile filter, providing optimum filtering performance in most soils. Megaflo has a formed invert at the bottom of the panel preventing loss of water into base soils, and has an open waterway with little restriction from support legs allowing for high flow rates. The HDPE core provides high chemical resistance, which is especially important for leachate collection and heap leaching applications.

It is cost-effective, easy to install and offers a subsoil drainage solution in a wide variety of applications.

The Megaflo and Zipcore were then covered with a layer of Kaytape S270, a heavy woven geofabric that spans over the Zipcore cusps,

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retaining an open flow path above the y Zipcore. The Kaytape d i D is followed by a layer of Bidim A6, which was tucked underneath the sides of the ZipCore. Bidim A6 is a non-woven, continuous filament needle-punched geotextile that has a high drainage capacity in both transmissivity and permittivity planes.

Compatibility testing of the tailings and Bidim were conducted in Kaytech’s laboratory to select the most appropriate grade to ensure durability of the fabrics’ filtering capacity.

For the total project, completed last year, Kaytech supplied 640 m of Megaflo and 3 000 m2 each of ZipCore, Kaytape and Bidim A6. Once the drain was installed, coarse tailings were cycloned to cover the newly installed drain, which extended beyond the drain and ultimately formed the perimeter wall.

Evidence of water flowing from the new system into the collector drains and no sign of water seepage on the dam wall are proof of the efficacy of the design and delivery of such a key project.

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ithout proper drainage on a tailings dam, water pressure would increase along the toe of the dam wall, causing water to seep through the toe as well as the wall itself. This increase in water pressure would also result in a decrease in the shear strength of the material deposited and ultimately affect the stability of the dam.

Fraser Alexander, the tailings consultant and facility manager at Samancor Chrome, specified a completely synthetic filter drain system as opposed to the traditional sand and stone design for economic and ease of implementation reasons. The synthetic filter drain was conceived jointly by Fraser Alexander, and geotextiles and geosynthetic solutions provider Kaytech, using Zipcore, Bidim A6, Megaflo and Kaytape products from Kaytech.

The combination of Kaytech’s materials and the vast experience of Fraser’s Tailings Division’s in this field, has made this project a success. The area around the dam wall perimeter was first cleared, shaped and then compacted in preparation. A central longitudinal groove was then formed, into which the Megaflo pipe

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The Millsell operation, part of Samancor’s Western chrome mines, at Marikana, near Rustenburg, acknowledges the necessity for proper drainage at its tailings facility and has taken the necessary steps to minimise its impact on the surrounding environment.

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 Water watch

REAL-TIME MONITORING

The smart solution Mines may understand the need to monitor water discharge and groundwater systems, but should implement long-term in-situ monitoring plans in conjunction with routine scheduled checks to deliver the best results for the mine and the environment, says SM Enviro’s MD, Vic Crüger.

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lot of mines have monitoring programmes in place, as is required by law. “I believe, however, that long-term in-situ monitoring plans are more efficient as they offer more accurate data. Detailed trends can be drawn up from this data and the possibility of missing an ‘event’ is almost eliminated. I’m not saying real-time monitoring should replace existing monitoring

programmes, but should rather complement it,” explains Crüger.

SM Enviro offers a large range of on-site process instrumentation to monitor and control all industrial water streams and sources.

“Customers are, however, as equally attracted to our service policy as they are to our equipment. We provide free on-site maintenance for a period of three months on any equipment purchased, with a guaranteed response

Groundwater Monitoring Dewatering Acid Mine Drainage Longterm deployment Telemetry Handheld measurements Data logging and Management Contact us for more information: Telephone: (012) 755 8016 Fax: 086 658 5749 E-mail: sales@smenviro.co.za or

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Water watch

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â&#x20AC;&#x153;Acid mine drainage (AMD) is a tricky application â&#x20AC;&#x201C; we do not always know what to expect.

Standard equipment often fails due to the harsh conditions, very low pH and extreme depths. A lot of additional unknowns make it difficult to specify a solution,â&#x20AC;? CrĂźger reveals.

SM Enviroâ&#x20AC;&#x2122;s titanium Level Troll can handle aggressive applications and has a battery life of up to 10 years, depending on the logging interval. The RuggedCable utilises titanium twist lock connectors and is available in

enables them to perform water quality profiles in the shaft.

Samples can also be taken at specific depths for parameter analysis in the lab that cannot be measured in real time. â&#x20AC;&#x153;We were awarded this contract by the Council for Geoscience.

Realising the need for an off-the-shelf solution, we approached our partner, Sea & Sun Technology in Germany, to develop an instrument specifically for this application.

The solution is an instrument designed for oceanographic applications that can handle the pressures at ocean depths. It has simply been adapted to suit AMD requirements.

Outside of AMD applications, SM Environ has also been involved in tailings dams monitoring for overflow and water quality. â&#x20AC;&#x153;We are currently monitoring effluent discharge in real time, with data updating hourly at 31 sites in Gauteng and another five in the Free State. We are further under way with a dewar W at c h e t tering programme for an More people opencast mine, where we have a mobile will be measuring and phone than a transmitting data from toilet.

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customised lengths up to 1 219 m. Equipment designed for groundwater monitoring is often used for AMD applications, which sometimes works. However, the equipment is not suited to the application in many instances and large data gaps result or equipment simply fails and monitoring stops. â&#x20AC;&#x153;We are currently monitoring four shafts for the Department of Water Affairs (DWA) using a telemetry device that takes hourly level and temperature readings and sends this information to our database once a day.

Our technicians are notified by text message in case of equipment failure, alarms or many other preconfigured conditions. The telemetry device is also fitted with a motion detector to notify the user if tampered with. All equipment has been installed in an enclosure designed specifically to deter vandals.â&#x20AC;?

SM Enviro also has a multi-parameter instrument from Germany that monitors depth, temperature, pressure, dissolved oxygen, ORP, pH and electrical conductivity. The instrument can be deployed up to a depth of 3Â 500Â m using a 12Â V winch with a data cable running to the surface to allow researchers to view the information in real time. This

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time of less than 24 hours anywhere in South Africa or Namibia. We offer 72 hours on-site support response time throughout Southern Africa, which is dependant only on visa processing times and flight availability. We have completed supply and installation projects as far afield as Libya.â&#x20AC;?

CrĂźger says the company is seeing an increasing interest in remote monitoring (webbased systems) and data capturing. These may have initial capital costs, but ultimately the cost of ownership is relatively low. With rising labour and fuel costs, the option is becoming popular.

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STEELPOORT SAVVY

A new dewatering depot Thanks to the growing demand for its products and services from the numerous mining operations in the area, Xylem Water Solutions South Africa will soon open a brand new rental depot in Steelpoort, Limpopo.

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he site for the new depot has already been identified and construction is due to start in the next few weeks. The new depot will be fully operational by the second quarter of 2013. This is the company’s fourth rental depot in South Africa.

“We are noticing an increased demand for dewatering services to be supplied as a complete package, including the pump and water treatment systems, engineering expertise and project management. Xylem Water Solutions on-site dewatering service provides customers with turnkey solutions from a single source. This limits customers’ administration and management efforts and provides peace of mind as they are contracting dewatering experts to take care of the job,” says Harry Steyn, general manager of Xylem Water Solutions South Africa’s rental division.

“Xylem Water Solutions South Africa’s dedicated dewatering rental services are designed to cater specifically to the needs of local customers. Each rental fleet is organised to align with our local customers specific service requirements. Xylem’s goal is to offer flexible dewatering rental services and to respond to customers’ needs as rapidly as possible. In addition to our extensive range of Flygt submersible pumps, our rental fleet now also includes the Godwin diesel surface pump, which is ideal for mining applications, bypassing sewer systems, drainage and large water transfer projects. The Godwin portfolio includes a full range of ‘silent’ models that are specifically designed for densely populated areas,” Steyn continues.

The beauty of Xylem’s service means that customers don’t have to invest in auxiliary equipment purchases that are needed for just as long as the project requires.

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 Underground mining

REDPATH MINING SA

Shaft sinkers, not contract Ockert Douglas, newly appointed MD of Redpath Group’s local subsidiary, has stepped into the management position with the intention of achieving two primary targets: sustainable growth and changing the industry’s perception of “who we are and what we do”, he tells Laura Cornish.

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ppointed as new MD in December last year, Douglas has wasted no time implementing strategies aimed at achieving significant growth for Redpath Mining South Africa.

Changing the perception “First and foremost we need to change the industry’s perception of what we do. In Africa, we are an infrastructure

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developer and a shaft sinker. Underground contract mining is a speciality in North America and Australia for Redpath and holds interest for us here in the future,” he states. Its Canada-based parent company, the Redpath Group, has over 50 years of shaft sinking experience and over 100 years through its wholly owned European company. Douglas is looking to leverage that experience locally and across Africa, and has already positioned

the company to take on its first deep level shaft sinking project.

“We are the youngest son of one of the biggest engineering, mine development and shaft sinking companies in the world, leaving little doubt that our shaft sinking growth potential is open-ended,” former MD, Jimmy Erasmus notes. Redpath’s Canadian company has sunk 74 shafts around the world to date and is currently busy with another seven.

 Underground mining

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1.4 million children die every year from diarrhoea caused by unclean water and poor sanitation – that’s 4 000 deaths a day or one child every 20 seconds (UNICEF).

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“We need to change the industry’s perception of what we do. In Africa, we are an infrastructure developer and a shaft sinker.” Ockert Douglas and experienced personnel; we have the capital and the equipment and are ready to take this business forward. I must point out, however, that we are a medium-sized contractor and have no intention of being or competing with the biggest shaft sinking and development contractors for the foreseeable future, but one of the best in terms of safety, quality and delivery.”

Growing its African footprint

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Redpath’s European company has sunk over 500 shafts totalling 210 000 m including 190 freeze shafts totalling 37 000 m and is currently sinking two freeze shafts in Russia.

Erasmus will continue to play an active role in the company as chairman and will facilitate communication between Redpath Mining SA and Canada. “Erasmus has solid and well-established relationships with the industry and remains pivotal to the projects we anticipate securing in 2016 and 2017.”

The company has already brought in some “dynamic” young staff who will constitute a fraction of its senior management team.

“We now have the right balance of young

The second aspect of Redpath Mining SA’s growth strategy is building critical mass – which means accumulating project work in Africa. “This has always been our mandate, but you need to create a solid base first and then build up from there, which is what we have been working towards. We want to achieve comfortable growth levels – at a rate where we can still manage and control.

Under no circumstances will we allow our safety achievements to be shadowed by our growth,” Erasmus points out.

The company has tendered on six shaft sinking projects this year, three of which are not in South Africa. “We are hoping to secure an underground horizontal development contract with an Australian company in Tanzania,” Douglas notes.

Changing its approach and methodology “While ensuring quality delivery and project execution is above standard is common practice for us, we are working on changing our thinking and approach to adopting the methodologies and technological practices of our Canadian parent – particularly in terms of handheld machines and mechanical drilling.”

Redpath’s approach to projects combines global competencies and skills with innovative techniques, regulatory knowledge, regional expertise and cultural sensitivity.

According to Redpath Canada: “This allows us to provide timely front-end engineering and design models, as well as selection and sourcing of hoisting facilities, to fast-track any shaft project. This seamless project planning phase has continually proven to yield high-quality products that exceed our clients’ expectations.”

In order to achieve this locally, Redpath Mining SA is intent on training. Douglas says he will establish a training centre on head office property (in addition to on-site training), which will develop and elevate employee’s skills. The company employs 800 people.

“We have also purchased a winder capable of sinking a 2 000 m deep shaft. We will use the winder to demonstrate our shaft sinking capabilities and commitments to potential clients going forwards – when it is not in use of course,” he explains.

Innovative problem solvers The company was recently contracted to rehabilitate a 2 000 m deep, 7 m diameter ventilation shaft in the Free State. “The collapse had started gradually and become progressively worse over time,” Douglas explains. “We will now rehabilitate the collapsed portion, from 120 to 240 m.”

The project will showcase the company’s innovative approach to solving challenges. A vetter bag will be installed at 240 m, which will expand and block the shaft. Aerated and coloured cement will be pumped Douglas’s experience Douglas has been in the shaft and decline development mining sector for 20 years.

Prior to Redpath, he was the business development director at Aveng Mining (Grinaker-LTA) and before he worked at Gold Fields Cementation and Shaft Sinkers.

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 Underground mining Redpath Mining South Africa is eager to take on its first shaft sinking project

into the collapsed shaft area, which will function like a plug. The remainder of the shaft (to surface) will then be filled with cement following which the shaft can be

resunk. “We will know we have reached the plug because of its different colour. Because it is aerated, it is softer, which will enable us to blast it out.”

Douglas estimates the project to take about nine months – meaning it should be completed towards the beginning of next year.

Redpath South Africa is also busy with a major decline sinking project in Botswana for Gem Diamonds. Due to the unstable, sand-like quality in the area, the company developed an innovative development solution to counteract the problem. “We developed a structural ring shield that provides support and enables us to line the decline (in rings using precast cement segments) as we progress.”

To date, the company has installed over 540 rings and over 1 100 will have been installed once it reaches the basal rock layer.

The company is also a permanent contractor on-site at Northam Platinum where it is working on an underground decline development at the Zondereinde deep level platinum mine. It is also rehabilitating three shafts for Gold Field’s South Deep operation.

We’re passionate about mining

It’s our passion for mining and dedication to our customers that inspires us to deliver excellent customer service. At Mining and Rock Excavation Technique we’re driven to optimise our customers productivity. www.atlascopco.co.za

 Underground mining

RUSTENBURG PLATINUM MINES

20 side-discharge hopper wagons en route Anglo American Platinum’s Rustenburg Platinum Mines has placed an order with DCD Rolling Stock for 20 new side-discharge hopper wagons that will be used to transport platinum ore from the mine’s various shafts to the processing plant.

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anufacture is under way at DCD Rolling Stock’s facility in Boksburg.

The first units have already been delivered, with the final wagons to be delivered as scheduled in June.

DCD Rolling Stock has a longstanding relationship with Anglo American Platinum’s Rustenburg Mines, spanning about 20 years, that has seen the company supply a number of hopper wagons to the mine.

Daryl Leggitt, technical manager at DCD Rolling Stock, says the company has also worked alongside the mine’s engineers over the past decade to adjust the design of certain hoppers to suit changing mechanical and safety requirements, and to refurbish existing hopper wagons.

The design of the units in the latest order features a unique safety mechanism on the bottom discharge doors that prevents the doors opening accidentally in transit and creating spillage, which presents a major safety risk. “We call this a ‘central shaft over top dead centre locking device’ and it has been designed specifically for Rustenburg Platinum Mines,” says Leggitt.

“The device comprises three offset levers connected to the doors with three links per door. The levers have two end stops to ensure that they rotate over the centre position, ensuring that the doors cannot open accidentally. As an additional safety feature, a pneumatically operated interlock is included, featuring a cam and hook that lock into place once the doors are fully closed.”

The discharge hopper wagons, with a gross mass of 85 t, have payload volumes of 26 m3 with 5 m3 volume reducers. The hoppers’ body and underframe comprise an all-welded construction utilising S355JR steel, delivering an increase in strength

of about 18% compared to the previous hopper wagons supplied. The body ends, centre gable and volume reducer are angled to avoid any hang-up of ore during unloading operations.

The wagons will be fitted with high-impact and wear-resistant body liners manufactured from Tivar GR12 material, 20 mm thick on the body ends and volume reducer, and 12 mm thick on the lower half of the centre gable. The braking system combines vacuum and air brakes, with each system capable of operating independently.

The wagons will also be equipped with two self-steer HS Mk VII bogies manufactured from new components to comply with the latest Transnet specifications.

capability that allows it to offer a total rolling stock package, from design and manufacture to refurbishing and modernising bogies and supporting the aftersales market for bogies, including supply of renewal parts.

The company has its own accredited quality, environmental and health & safety systems in place – SABS ISO 9001:2008, Moody International BS EN ISO 14001:2004 and Moody International BSI OHSAS 18001 – which ensure that manufacturing processes are carried out under controlled conditions to mitigate their impact on the environment and to international quality standards.

DCD Rolling Stock has been in business for more than 100 years and has designed 4 000 underground locomotives.

International systems house DCD Rolling Stock, part of the DCD conglomerate (previously DCD-Dorbyl), operates as an international systems house with an in-house

DCD Rolling Stock is manufacturing 20 side-discharge hopper wagons for Rustenburg Platinum Mines

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 Underground mining

WOMEN UNDERGROUND

A hard-hitting reality In a move that promised greater gender equality, women were allowed to enter the traditionally all-male world of underground work in South African mines in the 1990s. But it is time the industry and authorities reflect and take stock of the consequences of this decision.

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ccording to Dr Moreshnee Govender, programme manager in occupational health and safety at Wits University’s Centre for Sustainability in Mining and Industry (CSMI), women face some particular dangers when working underground, many of which are not openly discussed with a view to a sustainable solution.

Among the more chilling of these was the rape and murder of a woman mineworker last year while working underground.

Less dramatic but equally important issues relate to the suitability of technology, including protective equipment and underground facilities; gender attitudes, including work organisation; and design, which impacts on the health and safety of these workers.

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“There is a need for an open forum to reflect on our collective experience in the last decade since women have been working underground, and it should include not just

Have we adequately addressed the issue of safety of women miners in the underground mine work environment? management, the unions and government, but also women mineworkers themselves along with academics and researchers,” says Govender. “This sort of forum will help us to ask the right questions and plan the best way

forward towards sustainable solutions within our context.”

Since the law changed and the Mining Charter committed to employ more women, their share of employment in this sector has grown from less than 3% to over 10% overall.

Under pressure from high unemployment, many have opted for those underground jobs previously performed only by men.

“This is a complex process,” Govender continues. “It’s not as simple as just saying that the law now allows women to work underground and policy promotes this opportunity, so implementation will follow accordingly.

We have a responsibility to do more. We need to go beyond policy, reflect on both the direct and indirect consequences for women in this unique workplace, and use this evidence to inform current and future practice.” She

 Underground mining LEFT Since the law changed and the Mining Charter committed to employ more women, their share of employment in this sector has grown from less than 3% to over 10% overall RIGHT Have we adequately addressed the issue of safety of women miners in the underground mine work environment?

Photographer: Philip Mostert

likens the process to a sort of ‘social experiment’ – the results of which now need some careful evaluation.

“Women have been working underground for 10 years or so; we should have some statistics relating to occupational injuries and diseases, for example, and some record of what the issues for concern are.

“We know that underground mining is a dangerous environment, not just from the accidents but from the diseases that workers might sustain. We still need to be asking the question: Have we adequately addressed the issue of safety of women miners in the underground mine work environment? We also need to reflect on the interventions we’ve made to date and what impacts they have had. Sadly, I’m finding that not much is said about it in the public domain.”

Govender’s background as a medical doctor is only part of the skill set that she offers this field. Her focus on taking the issue beyond policy toward practical and sustainable solutions stems from identifying design problems in a hospital environment, from which she entered the multidisciplinary world of ergonomics in industry.

After completing a Diploma in Occupational Safety and Health in Practice at the Swedish Institute for Working Life, she became inspired by the prospect of finding solutions through a fuller appreciation of technology and design re-engineering. She followed this up with a master’s degree in ergonomics, also in Sweden.

Looking ahead at issues increasingly likely to be tackled by the underground mining sector, she highlights mechanisation as ripe for discussion. “Mechanised mining is a big issue currently.

You would think that this could lead to the involvement of more women in mining, as it suggests less manually demanding work. It would be a good area for an open forum to engage upon.

“We have an excellent opportunity to be at the forefront of not only the research and development of appropriate technologies for women that support them in their pioneering new roles in the challenging underground setting, but also in publicising our experience as a country in truly addressing equity in the workplace,” she states. “This would not only benefit women, but men as well and will be a valuable experience to be shared with the rest of the continent and even other parts of the world.”

The starting point where women are given a voice among the other industry stakeholders in a forum where experiences can be articulated and constructive directions can be forged to be relevant at the coal face is yet to be reached. Dr Govender is working to make this a reality.

Dr Moreshnee Govender, programme manager in Occupational Health and Safety at Wits University’s Centre for Sustainability in Mining and Industry

 Underwater mining

DEBMARINE NAMIBIA

Marine miner trawls for more carats Debmarine Namibia, which has successfully mined diamonds below the ocean floor off the south-western coast of Namibia, signalled its commitment to its business by revealing its latest annual production-increasing investment, writes Reggie Sikhakhane.

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ebmarine Namibia, which is 50% owned by De Beers and 50% by the government of Namibia, unveiled its newest mining vessel, the MV [motor vessel] Mafuta, which was purchased for N$650 million [Namibian dollars] (R650 million). The MV Mafuta will be the largest mining vessel in the Debmarine Namibia five vessel fleet and is expected to produce approximately 350 000 carats annually, equivalent to 30% of Debmarine Namibia’s total production.

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The new vessel was unveiled at a glittering ceremony in Windhoek, Namibia, on 8 April 2013.

“The partnership between the government of Namibia and De Beers is a fantastic model of what is achievable when private and public sector collaborate to create meaningful economic empowerment for the people of the country,” the president of Namibia, Hifikepunye Pohamba, said at the event.

Namibia has the richest known

marine diamond deposits in the world, estimated at more than 80 million carats – approximately 90% of the country’s total diamond resources. Debmarine Namibia recovers approximately one million carats every year from the sea floor, accounting for more than half the total diamond production of Namibia Diamond Corporation (Namdeb).

Debmarine's new MV Mafuta. It is expected to recover 350 000 carats per annum

 Underwater mining The company’s off-shore mining operations reach depths of up to 140 m, and it has applied leading off-shore mining technology that has seen marine mining surpass land-based mining in yearly production in Namibia. The company employs about 780 people.

“It is through the continued hard work of our workforce, their diligence and commitment that Namdeb is today the largest producer of diamonds in Namibia,” said Namdeb’s CEO, Otto Shikongo.

He added that in 2012, Namdeb’s turnover reached around N$4 billion, and the company accounted for around N$1.3 billion to the Namibian treasury in taxes including royalties, as well as N$538 million in dividends to its shareholding company.

“We believe we are unrivalled in our contribution to the Namibian Treasury in that respect,” he remarks.

Namibia’s minister of Mines and Energy, Isak Katali, also spoke at the ceremony and congratulated Namdeb for attaining 10 years of operations in Namibia.

“It is pleasing that Debmarine Namibia continues to lead the world in marine

mining technology and I hope that Debmarine Namibia can grow further to enhance its position as a true global leader.”

MV Mafuta is registered with the port of Lüderitz in Namibia and employs approximately 57 crew members.

About the MV Mafuta

Outlook

The MV Mafuta was purchased from De Beers Consolidated Mines for N$650 million in November 2012. Previously known as the Peace in Africa, , it was ‘christened’ the MV Mafuta – which means seas or great waters in the Oshiwambo language of Namibia – following its acquisition.. The vessel is the largest in the Debmarine Namibia fleet of five vessels.

The other vessels are the MV Debmar Atlantic, the MV Debmar Pacific, the MV Gariep and the MV Grand Banks.

The MV Mafuta is about 170 m in length, has a depth of 15 m, breadth of 24 m and weighs approximately 16 000 t. The vessel employs crawler-mounted technology.

The company revealed that in 2013, Debmarine Namibia will look to increase operational efficiencies through the advancement of exploration sampling and the implementation of new resource models and technological improvements to mining tools and technical systems.

Debmarine Namibia will continue to focus on maturing its 2050 vision through ongoing exploration, sampling, beach accretion and development of technologies to mine the mid-water. It pointed out that as land and marine extension projects gather momentum, the company is confident it will secure capital for future development and return long-term shareholder value.

 Advertorial

SOFTWARE STANDARDISATION

The key to sustainable growth in mining?

No! Yes! Well… it depends on what you mean by standardisation (and who you ask).

If what you mean is throwing out what you have and implementing one-size-fits-all solutions across the board, standardisation might very well be the key to failure.

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any mining companies have fruitlessly attempted to standardise their way into optimisation, cycling through countless vendors and products to find a single standardised tool or provider that will get the job done everywhere, every time. But standardisation could never mean always doing things the same everywhere, simply because such a definition fails to capture the real value of either standardisation or deviation.

Nowhere has the dream of standardisation been more active than in the world of mining technical software solutions.

Finding standardised ways of storing, exchanging and interpreting mining data has been suggested and rejected by many companies, over and over again.

The value of deviation Mines and software providers have spent millions on developing optimised, purpose-fit algorithms, data structures and even hardware technologies that result in context-ideal solutions for a given mining type or mine. These optimised products are often simply the best tool for the job in the places they are used and replacing them might lead to decreasing performance instead of optimised outcomes.

Specifically in the world of mining technical software such as mine planning and scheduling tools, non-standardised solutions are mostly the result of specified requirements and not of deviant purchasing.

The value of standardisation If you are reading this, then the chances are you have read a host of academic papers shouting from the rooftops the value of standardising – giving reasons such as simplified technology landscapes, vendor

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management, integrated reporting and much more.

I for one don’t challenge any of these, except to say that there are ways and means to achieve the desired outcome. At MineRP, we have invested heavily in the development of standards-based enterprise integration solutions. It might surprise you

We have invested heavily in the development of standards-based enterprise integration solutions then that this article seems to suggest that standardisation is not the answer. Well, what we’re suggesting is that the solution does not lie with implementing the same software everywhere, but rather with the implementation of a spatially aware, open standards-based translation and standardisation framework. This is exactly what MineRP developed with its MineRP

Crew efficiency with MineRP SpatialDash

Enterprise Integration framework for spatially related mining technical information. MineRP will allow your discipline specialists to continue using the software that works for them, yet with the ability to freely share, report and interoperate on data created in the various traditional silos.

Spatially relate, interoperate and optimise MineRP is much more than a traditional data warehouse that transforms data into a nice picture though. With specialised data convertors and connectors, mines implementing the MineRP framework are able to seamlessly share data at the operational as well as executive levels, finally delivering on the promise of mining technical integration and standardisation without the need to replace source systems across the organisation.

For more information about the MineRP Enterprise Integration solutions, please visit www.minerpsolutions.com or contact Empie Strydom estrydom@minerpsolutions.com

 Mining Services

BIDVEST LAUNDRY

Enterprise development clean-up There can be little doubt that the mining industry is facing numerous challenges at present – Mining Charter compliance, directives around BEE and enterprise development, for a start. It seems strange to suggest that something as simple as a laundry service could assist mines in meeting their legislative challenges. thereby assist the mine in promoting enterprise development, while also uplifting the community itself,” says Coates.

“Moreover, by stimulating job creation and skills development in the region, we will be able to ensure that both Bidvest Laundry and the mine in question are able to leave a lasting legacy in the area.”

Bidvest Laundry has been involved in a public-private partnership with the government of Lesotho and Netcare in the development of a 450-bed hospital, says Coates. Bidvest has put in place some R2 million worth of equipment and is currently training local people to operate and maintain it. “Our plan now is to extrapolate this concept into the mining sector.

“We already have standard Montana contracts with a number of the major players in the sector, but these offer very little in terms of community improvement. After all, what the standard contract effectively boils down to is a situation where these mines are spending a lot

By W of money on their launthe time a person feels thirsty, dry contracts with little his or her body to show for it at the end. has lost over 1% of This is why our new soluits total water tion is ideal.” amount.

Coates explains that Did Bidvest understands that teaching members of the local community to operate the machinery in a laundry is reasonably simple. Ensuring that they are able to maintain it as a successful business operation for years to come is, however, the true measure of success. For this reason, business training and management is an integral and vital part of the skills development process.

“This truly is a win-win situation for everyone; the local community are provided with jobs, skills and business acumen while the mines are able to develop the local communities, improve both their BEE and enterprise development initiatives and ultimately save costs,” he concludes.

yo

Y

et that is exactly what Andrew Coates, sales director at Bidvest Laundry Group, proposes. The right laundry implementation can boost BEE scorecards, enlist local community commitment and drive upliftment – all while being a boon to enterprise development, he says.

“Bidvest Montana provides laundry equipment, spares and maintenance, and delivers what we refer to as on-premise laundry (OPL) solutions,” he says.

Coates describes OPL as a one-stop-shop offering, whereby the company can supply the required laundry equipment, design and implement a laundry for a client, and provide the skills to operate and maintain it. In fact, he adds, mining firms such as Gold Fields, AngloGold Ashanti and Harmony already use such solutions.

“What we are now proposing is to provide a solution of this nature to the mines, but instead of merely managing it ourselves for the contracted period, we want to partner with entrepreneurs in the local communities by building businesses that are owned by entrepreneurs in the community. We would

r W at c h

INDEX TO ADVERTISERS AMEC Minproc Atlas Copco Atlas Copco CTS Babcock Bell Equipment SA Bidvest Group BLC Plant Company Buildmax/Diesel Power C.S.T. 29 Fleming Gulf Golder Associates Africa Group Five Housing Husqvarna Hydrodifusion Fittings

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2 72 24 OBC 27 28 75 43 IFC 25 8-10 32 7 77

Imerys South Africa 31 Johnson Crane Hire 40 Kalcon/WBHO Construction 16 Kaytech 65 MC Process 56 MineRP 79 Minopex 20 Mintails 51 Nalco Africa 63 NuWater 4-6 Osborn Engineering 17 Osh Expo Africa 29 Pumps Valves & Pipes Watertec Africa 53 Quadrex 57

u k now?

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69 11 60 IBC 67 66 41 21 33 35 13 59 61 68