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Environmental performance
DRDGOLD acknowledges that the long-term sustainability of its business depends on the way in which its operations are managed and the effects of these operations on their surrounding communities and natural environments. The environmental dimension of sustainability looks at the ways in which the company has an impact on living and non-living natural systems, ecosystems, land, air and water.The activities of mining and processing have the potential to affect all of these entities.
Updated in 2009, the group’s Environmental Policy states that DRDGOLD is committed to the responsible management of the environment in which it operates, adopting and implementing environmental best practice as outlined in the National Environmental Management Act, 1998.
Recognising that the environment is held in trust for the people, the policy commits DRDGOLD to:
- integrating environmental management into the company’s business and planning so as to minimise the influence of its activities on the receiving environment, through internal risk assessments and environmental impact assessments;
- complying with relevant environmental legislation as a minimum and adopting and applying the best practicable environmental option with respect to current activities as well as prospective projects;
- evaluating, through a process of monitoring, auditing and reviewing by management, the success of the management and mitigation measures applied; and
- ensuring that environmental risks and potential emergencies are identified and managed through effective controls and procedures as identified in the applicable Environmental Management Programmes.
Compliance with environmental legislation
The environmental function at DRDGOLD is managed in line with the environmental legislation and regulations of, in particular, the Department of Mineral Resources, the Department of Water and Environmental Affairs and the National Nuclear Regulator. Consultations are also held with the regulatory authorities.
As required by legislation, Environmental Management Plans (EMPs) are in place at all of the group’s active operations. Developed by the company, these plans address the impacts and potential impacts on the environment by DRDGOLD as well the measures to manage, monitor and mitigate these impacts. A biennial audit is undertaken to assess compliance with the EMP and submitted to the Department of Mineral Resources (DMR). The EMP is a dynamic document and informed by any changes in legislation. All new projects are subject to Environmental Impact Assessments (EIAs) which include a high degree of public participation.
Revised EMPs have been submitted to the DMR: for Blyvoor and ERPM in 2007, and for Crown in 2009, and approval is awaited. All the operations have applied for integrated water use licences and are awaiting approval from the authorities. In the interim, water is managed in terms of previously approved water permits.
No fines were imposed on any of the group’s operations during 2010 in respect of environmental management.
Environmental management
The Board of Directors and, in particular, its Transformation and Sustainable Development Committee oversee the environmental performance of the group. DRDGOLD’s General Manager: Technical Services takes overall responsibility for the discipline across the group and monitors performance against the EMPs. All key environmental staff and contractors report into this function, although the ultimate responsibility for environmental practices at an operational level resides with operational management.
Crown and Blyvoor have environmental managers and radiation protection officers on site. ERPM contracts Malepa Holdings to carry out the radiation protection function. This contractor also undertakes radiation protection specialist duties at all DRDGOLD operations.
The responsibility for the monitoring of radiation at the discontinued operations of Durban Roodepoort Deep and Rand Leases has been taken over by Mintails South Africa, which purchased these assets several years ago.
During 2010, DRDGOLD spent R44.6 million on environmental issues.
Blyvoor takes firm control of slimes spillage
Before
After
In spite of heavy rains during summer, no reportable slimes spillages occurred at Blyvoor during the year under review. This was the result of a concerted effort to reduce spills at this operation. The most significant aspect is that the mine now has two containment dams – the first was built in September 2008 and the second in July 2009 – to capture slimes spillage (in the event of pump failure, for example) before the surrounding areas can be contaminated. More commonly known as containment spillage paddocks, these dams are of a substantial size – the most recently completed being 50 metres wide and 2.5 metres high.The 10-hectare area around this paddock, which suffered the effects of spillages in the past, has been cleaned up.
Another important step was to replace the 3 kilometres of steel pipelines feeding slurry to the plant with high density polyethylene piping at a cost of some R3 million. This was done because the steel columns had been prone to bursting and leaking. Apart from reducing spillage and ensuring a more reliable supply of slurry to the plant, the lower friction associated with the new pipes has reduced the energy costs of pumping.
The surfaces of a number of reclamation sites were also flattened to reduce the possibility of spills spreading.
Stakeholder engagement
Together with other mines in the area, Blyvoor belongs to the Mining Interest Group (MIG). This group gets together whenever needed to discuss common interests and problems. It meets with the Department of Mineral Resources, the Department of Water and Environmental Affairs and the National Nuclear Regulator on a regular basis. Representatives of local authorities and municipalities attend the group’s meetings. The MIG is represented on the implementation task team set up by government to look at possible, practical solutions to pollution issues regarding the Wonderfontein Spruit.
DRDGOLD participates in a number of public groups, including the Ekurhuleni Business Forum, the Blesbok Spruit Forum, the Klip River Forum, the Rand Water Catchment Quality Forum, the Heriotdale Business Forum, the Mooi River Forum, the Far West Rand Technical Working Group and the Far West Rand Dolomitic Water Association.
Environmental auditing and monitoring
DRDGOLD contracts Sibanekile Environmental Services to perform the annual closure liability and the EMP performance assessments. Various contractors are used for the updating of EMPs, the carrying out of EIAs and for rehabilitation projects.
Malepa Holdings undertakes the annual Government Notice (GN) 704 (guidelines for the use of water in mining) audits and Annergarn Environmental Research, a leading dust monitoring agency in southern Africa, performs dust sampling and analysis at all operations. National Nuclear Regulator (NNR) audits are conducted once a year.
Environmental incidents
Environmental incidents are monitored and reported to the relevant authorities as is required. In assessing environmental incidents DRDGOLD follows:
- the categories set out in the NNR Certificate of Registration;
- Chapter 23 of the Mine Health and Safety Act which sets out Regulations for the Reporting of Accidents and Dangerous Occurrences; and
- GN 704, Regulation 2 with respect to any possible effect on a watercourse.
Only one reportable environmental incident occurred during the year. This happened on 7 October 2009 at Crown where vandals removed the bolts of a pipe flange, resulting in approximately 1 500 tonnes of slimes spillage.The spill was reported and the area cleaned up. No watercourse was affected.
Six spills occurred in 2010 at Blyvoor as a result of burst reclamation pipes from slimes dams Nos 4 and 5. Five of these spills occurred in the first two months of the year while the pipe column was being changed. The sixth occurred as a result of a fire. The spills were all on the mine property and did not affect any watercourse. The volume of these spills has been estimated at approximately 3 600 tonnes and all six – about 50 hectares in all have been cleaned up.
Major environmental risks
The major environmental risks and concerns for DRDGOLD are those of air pollution (dust), water management (including the sourcing of water and polluted discharges), resource utilisation (and in particular the use of cyanide and timber), energy usage and land management and closure. Blyvoor has an added risk of sinkhole formation because of dewatered dolomites underlying its significant landholdings.
Air pollution
As DRDGOLD’s surface reserves and resources are contained in tailings dams, many of them situated in built-up areas, it follows that dust is an issue that the company deals with on a daily basis. It is addressed through ongoing environmental management and remediation measures such as vegetation and ridge ploughing.
Dust is monitored at 1 546 monitoring points at DRDGOLD’s operations (including closed mines) and sampled and analysed against the South African National Standards (SANS). In 2010, there was a 20% decrease – to 115 (2009: 143) – in the number of instances where the levels of dust exceeded the SANS standard. The results for all the operations are set out in the table above.
Crown, Ergo and ERPM have numerous monitoring points because of their proximity to residential areas in central Johannesburg. Crown has monthly meetings on site with inspectors from the Department of Mineral Resources to monitor compliance and assess the effectiveness of mitigating measures that are put in place to reduce dust emissions.
A dust register is kept at each operation to record complaints from the public. Crown received nine complaints during the year under review. When a complaint is registered it is addressed immediately. Usually the party/parties involved are invited to a meeting on site. Mitigating measures are then put in place. Complaints about dust are also discussed at quarterly community forum meetings which are held in the Ekurhuleni area.
| Operation | Points monitored 2010 | Number of exceedences 2010 | Number of exceedences 2009 | Exceedences as percentage of total 2010 | Exceedences as percentage of total 2009 |
| Crown | 934 | 90 | 104 | 10 | 11 |
| Ergo | 264 | 10 | 18 | 4 | 6 |
| ERPM | 288 | 15 | 21 | 5 | 7 |
| Blyvoor | 60 | 0 | 0 | 0 | 0 |
Mitigating measures to reduce dust include the use of vegetation where this is possible, watering down of active faces and areas, and rock cladding where necessary. During the year under review Crown completed 13.7 hectares and Blyvoor 1.4 hectares of side slope vegetation, while 70 hectares of profiling and cladding were completed at Ergo. (See case study below: DRDGOLD clads Ergo’s 791-hectare Brakpan Tailings Dam to suppress dust and prevent erosion) In total, DRDGOLD spent R35.8 million on mitigation measures.
All responsibilities regarding environmental management at Durban Roodepoort Deep and Rand Leases and the surface deposits at West Wits and West Rand Consolidated have been taken over by Mintails South Africa.
Water management
Water is a scarce resource and DRDGOLD endeavours to minimise the amount of water it uses. In 2010, total potable water usage by DRDGOLD amounted to 10 million cubic metres (m³). Water is extracted from underground at Blyvoor. As discussed in the case study below (Blyvoor’s water plant will halve discharge of underground water), Blyvoor has established a plant to treat some of this water to potable standards for use on the mine which will mean a substantial drop in the consumption of potable water at this operation.
The source of potable water at DRDGOLD’s operations is the Rand Water Board: at Blyvoor this is used for the two villages on site and for about 30% of the mining processes – for the rest extracted water is used; at ERPM it is used for domestic purposes; and at Crown, where there is no other source of water, it is used in all the mining processes. At Ergo, it is used for approximately 5% of the operational requirement.
Water quality and discharge volumes are monitored regularly. Details of the water usage by operation for 2010 are set out in the table below.
| Blyvoor | % | Crown | % | Ergo | % | ERPM | % | |||||
| 2010 | 2009 | change | 2010 | 2009 | change | 2010 | 2009 | change | 2010 | 2009 | change | |
| Potable water from external sources | 3 062 | 3 553 | -14 | 4 591 | 4 627 | -0.8 | 388* | 134 | +190 | 917** | 4 054 | -77 |
| Groundwater used | 2 588 | 2 314 | +12 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Water recycled in process | 3 392 | 3 359 | +1 | N/A | N/A | N/A | 7 120 | N/A | N/A | N/A | N/A | N/A |
* Water consumption rose at Ergo as the operation reached steady state production in 2010.
** Water consumption dropped sharply at ERPM following the closure of underground mining activities.
Wonderfontein Spruit
Blyvoor continues to discharge between 8 and 13 megalitres per day of fissure water from underground into the Wonderfontein Spruit (stream). During 2010, the water discharged into this watercourse amounted to 4.9 million cubic metres. Samples of this water are taken every week and the results sent to the Tlokwe Municipality and the Department of Water and Environmental Affairs (DWEA).The water was found to be of relatively good quality as these results indicate:
- pH – 8.5;
- EC (mS/m) – 126;
- suspended solids (mg/L) – 20; and
- sulphates (mg/L) – 572.
The water treatment plant currently being commissioned at Blyvoor will reduce the discharge of water into the Wonderfontein Spruit by approximately 175 megalitres a month. The use of water from the Rand Water Board will also reduce by a similar amount.
As a member of the Mining Interest Group, Blyvoor, together with the regulators, is looking at pollution in the sediments of the ‘spruit’ from historical mining activities and determining what action, if any, should be undertaken to clean up this watercourse.
The regulators have produced a report called the Remediation Action Plan in which certain areas along this stream have been identified for further investigation. Implementation task teams will now be established to carry out these investigations.
Western and Central Basin water
The Western Basin of the Witwatersrand goldfields has been filling with water after mining operations stopped in the early 2000s and this water – known as acid mine drainage (AMD) – started to decant on surface in 2002.
In response to this, a Section 21 company, the Western Basin Environmental Corporation, was formed by the mines involved – Randfontein Estates (Harmony), Mogale Gold (Mintails) and West Wits (DRDGOLD) – to investigate a sustainable solution to this water which is polluted and needs to be treated. A management agreement was signed with the Western Utilities Corporation (WUC), a wholly owned subsidiary of AIM-listed Watermark Global plc, to find a solution.
For two years after the establishment of WUC, DRDGOLD, in collaboration with Harmony and Mintails, co-funded the costs of treating AMD before discharging it into the Tweelopies Spruit. The mines and the regulator agreed on the two-year period in order to allow time to investigate and implement a long-term sustainable solution.
DRDGOLD, Mintails and Harmony established a set of commercial parameters and approvals with the regulator which paved the way for WUC to obtain private funding in addition to the contribution that the mining companies were making to treatment costs.
Armed with these approvals, WUC was able to raise more than R75 million on the capital markets which it applied, during the course of the next four years, towards research and development and the construction of a pilot plant. In this period, it also conducted and completed a bankable feasibility study – the ultimate objective of the initiative – in accordance with commercial and regulatory parameters which were consistently agreed with government.
The feasibility study indicated that treating the Western Basin water, which amounts to 15 megalitres per day, would not be sustainable and that a minimum quantity of 75 megalitres per day would be required to achieve the economies of scale required. However, by combining this water with that of the Central (60 megalitres per day) and Eastern (75 megalitres per day) basins of the Witwatersrand goldfields, which have similar water problems, an economically viable water treatment plant could be established.
Studies indicated the best site for the plant is the currently disused High Density Separation water treatment plant at ERPM, which has an approximate capacity of 80 megalitres per day. A pipeline would connect the Western and Central basins to stop the discharge of any polluted water into the Tweelopies Spruit.
In late 2009 government was presented with a complete selfsustaining solution, capable of operating independently of any further financial assistance from the mines and of surviving the ultimate closure of the remaining few mines in the area.
In its response, DWEA indicated that it wanted to halt the water rise in the Central Basin at 400 metres below surface. The water is currently at 560 metres below surface and rising at 0.7 metres per day. In order to protect the ground water, this polluted underground water cannot be allowed to rise higher than 150 metres below surface. Timing is therefore critical – it is probably already too late to maintain the 400-metre level. In any case this would only be an interim solution, with the water being partially treated (it would still have high sulphate levels of around 2 600 milligrams per litre) before being discharged.
Following government’s rejection of WUC’s proposal, DRDGOLD participated with its WUC founding partners in putting together a revamped proposal in which the companies contribute a portion (with DRDGOLD providing approximately R13.5 million) of the funding required and government makes a contribution on behalf of the ownerless and derelict mines. This has been submitted to DWEA for approval. A response is awaited.
Resource utilisation
DRDGOLD is committed to using natural resources carefully and to reducing waste wherever possible.
| Item | 2010 | 2009 |
| Rock mined (ore and waste) | 781 188 | 1 263 000 |
| Sand recycled | 5 095 061 | 1 430 000 |
| Slimes recycled | 16 628 091 | 12 918 606 |
| Cyanide | 4 896 | 4 380 |
| Hydrochloric acid | 1 616 | 1 707 |
| Caustic soda | 1 640 | 1 694 |
| Lime | 53 331 | 50 854 |
| Carbon | 794 | 730 |
| Poly fuel/waxy fuel | 438 | 582 |
DRDGOLD uses a substantial amount of cyanide in the gold recovery process – 4 896 tonnes in 2010 (2009: 4 380 tonnes) – and recognises that its use poses a significant risk. Energy and chemicals company Sasol supplies cyanide to DRDGOLD’s operations. The company follows Sasol’s special procedures for the handling of cyanide once it has taken delivery of a consignment. The correct handling of cyanide forms part of the safety training for employees working in the gold plants.
Energy usage
In 2010, DRDGOLD reduced its consumption of petrol to 52 330 litres (2009: 73 124 litres) and of diesel to 2 079 311 litres (2009: 3 323 724 litres). This was primarily because of a decrease in the company’s activities, the main aspect of which was the cessation of underground mining at ERPM. To bring its consumption of direct energy down further, Blyvoor is moving from using diesel locomotives to more energy efficient battery operated locomotives. Also planned for implementation is the use of mechanical agitation rather than compressed air in the sewage plants on site.
DRDGOLD purchases electricity from state utility Eskom. Several projects have been implemented with respect to reducing the consumption of indirect energy. These include the following:
- a control system that switches geysers off during peak times at all houses in the mine villages at Blyvoor;
- changing to energy efficient light bulbs at Blyvoor;
- buying new energy efficient motors instead of rewinding motors under 22 kilowatts;
- installing prepaid meters in the DRD village; and
- upgrading of hot water calorifiers at ERPM’s change houses.
Projects that are currently being undertaken include:
- installing prepaid electricity meters in all houses in the Blyvoor mine villages; and
- investigating the use of compressed air generation at the operations. Currently this is one of the biggest consumers of electricity and the investigation will determine whether savings can be effected by changing to hydraulics, for example.
The only DRDGOLD operation pumping water from underground during the year under review was Blyvoor. This operation made adjustments to its schedule in order to reduce the power used during peak times by 9 megawatts. Most pumping takes place during off-peak times.
During 2010, DRDGOLD reduced its electricity consumption by 27%, to 2 358 301 gigajoules (2009: 3 217 025 gigajoules).
| Operation | 2010 | 2009 |
| Blyvoor | 1 390 161 | 1 517 872 |
| Crown | 575 791 | 739 498 |
| Ergo | 351 475 | 120 676 |
| ERPM | 40 874 | 810 547 |
| Total | 2 358 301 | 3 217 025 |
| Item | Blyvoor | Crown | Ergo | Total 2010 | Total 2009 |
| Petrol | 49 371 | 2 959 | - | 52 330 | 73 124 |
| Diesel | 841 590 | 997 721 | 240 000 | 2 079 311 | 3 323 724 |
| Waxy fuel* | 438 400 | - | - | 438 400 | 269 816 |
* It should be noted that last year’s report included a number for poly fuel. The use of this energy source was stopped in 2010 and replaced by waxy fuel.
Greenhouse gas emissions
DRDGOLD recognises that climate change presents a risk to its operations because of regulatory compliance and the costs associated with increased taxes, usage caps and tariff increases. While South Africa has not been a signatory to the Kyoto Protocol and does not have any specific legislation in place relating to greenhouse gas (GHG) emissions, it is likely that the country’s policies (and potentially legislation) will be guided by ongoing international climate change talks and that, post-2012, regulations will be imposed.
DRDGOLD has considered risks to the company posed by climate, and those to local communities, relating to:
- water scarcity and rising water tariffs;
- limited availability of electricity and rising tariffs;
- floods and increasing precipitation (which could have an impact on surface operations);
- food and water scarcity; and
- an increase in disease, which could have an impact on employees and communities.
As was the case last year, DRDGOLD engaged an external consultant, SDG Consulting, to undertake a GHG emissions survey in 2010. Compared with the previous year, emissions have declined because of a decrease in the company’s activities as referred above.
| Measure | 2010 | 2009 |
| Direct CO2 | 6 242 | 10 110 |
| Indirect CO2 | 786 101 | 895 928 |
| Travel | 751 | 862 |
| Total GHG | 792 924 | 906 901 |
| NOx | 3 019 | 3 506 |
| SOx | 5 571 | 6 503 |
| SO2 | 0 | 0 |
| VOC | 12 | 19 |
| Carbon monoxide | 31 | 49 |
| Methane | 0 | 0 |
| Ozone depleting substance | 0 | 0 |
| Particulate emissions | 272 | 188 |
Direct emissions of carbon dioxide (CO2) include all the emissions from liquid and waxy fuel consumed on site, excluding travel kilometres claimed by DRDGOLD employees. By far the greatest contributor to this is the diesel used by the operations.
Indirect CO2 emissions refer to the emissions generated in the production of the electricity that DRDGOLD consumes. Approximately 89% of Eskom’s electricity is derived from coal fired power stations, resulting in significant indirect emissions.
Nitrous oxide (NOx) and sulphur (SOx) emissions as well as particulate emissions primarily reflect emissions from diesel and electricity. The relatively large proportion of diesel source NOx recorded is a result of the higher emissions per unit (and therefore decreased efficiency) of diesel compared with electricity. The rise in particulate matter recorded is an indication of Eskom’s increased emissions through the year.
Volatile organic compound (VOC) and carbon monoxide emissions mostly record the relative diesel usage of the various operations of DRDGOLD. The relatively large proportion of particulate matter recorded from diesel sources is a reflection of higher emissions per unit (and therefore decreased efficiency) of diesel compared with electricity.
| Emission source | Blyvoor | Crown | ERPM | Ergo | Corporate office | Total |
| Direct CO2 | 3 083 | 2 547 | 0 | 613 | 0 | 6 242 |
| Indirect CO2 | 463 387 | 191 930 | 13 625 | 117 158 | 0 | 786 101 |
| Travel | 522 | 43 | 5 | 0 | 11 | 581 |
| Total GHG | 466 992 | 194 521 | 13 630 | 117 771 | 11 | 792 924 |
| NOx | 1 753 | 771 | 50 | 445 | 0 | 3 019 |
| SOx | 3 282 | 1 362 | 96 | 830 | 0 | 5 571 |
| SO2 | 0 | 0 | 0 | 0 | 0 | 0 |
| VOC | 5 | 6 | 0 | 1 | 0 | 12 |
| Carbon monoxide | 12 | 15 | 0 | 4 | 0 | 31 |
| Methane | 0 | 0 | 0 | 0 | 0 | 0 |
| Ozone depleting substance | 0 | 0 | 0 | 0 | 0 | 0 |
| Particulate emissions | 159 | 69 | 5 | 40 | 0 | 272 |
Land management, closure and biodiversity management
Blyvoor, Crown and ERPM manage 4 506, 1 942 and 1 469 hectares, respectively. The land disturbed by mining activities is 4 023 hectares in the case of Blyvoor and 688 hectares in the case of ERPM. Crown has cleared 239 hectares of land while 206 hectares have been cleared and developed or are in the process of being developed.
Rehabilitation
In 2010, DRDGOLD spent R31.5 million on rehabilitation.
ERPM continues with the rehabilitation of a redundant railway embankment and has started the rehabilitation of all the redundant shaft areas. This programme should be complete in 2011.
At Blyvoor, the No 4 slimes dam is being removed and the land is being restored to grassland standard. This operation has a budget of R200 000 a month for the demolition and rehabilitation of disused hostels. No longer required for employees, Annan Hostel is being knocked down and, concurrently, the site is being returned to grassland. This project should be completed by the end of calendar 2010. Rubble from this hostel is being used to fill two disused shafts – Annan Shaft and No 1 Shaft.
Sinkholes
Sinkholes and subsidences or dolines (shallow depressions) occur on the West Rand, which is underlain by dolomites – a type of limestone. Carbon dioxide-rich rainwater forms a weak acid and when then this seeps through surface soils, it can take up additional acids from plant roots. In effect, this means that groundwater is a weak acid and this has the effect of diluting the dolomites and accelerating their deterioration. This can result in sinkholes which, on average, are about 20 metres in diameter and 15 metres in depth, or dolines on the surface.
Blyoor monitors the occurrence of sinkholes very closely. Every six months, various points on surface are surveyed to measure if there is any ground subsidence. If there is a concern about any particular part of the mine property, this will be surveyed on a weekly basis. All water leaks are dealt with immediately and residents are encouraged to report any such leaks. When a sinkhole occurs, the area is fenced off until the ground has stabilised. The cavity is then filled in with building rubble or waste rock, capped with clay and re-vegetated. There were six sinkholes at Blyvoor in 2010 (nine in 2009), all of which were filled and rehabilitated.
Taking rehabilitation to another level
Blyvoor removed calcine from a site where it had been stockpiled, leaving a large depression in the land. The decision was taken to reshape this site and turn it into a dam, filling it with underground water that would otherwise have been discharged into the Wonderfontein Spruit.
The water was tested and found to be suitable for aquatic life. In February 2010, the dam was stocked with 5 000 fingerlings. The fish are doing well and bird life in the area is improving. The plan for the future is to introduce predatory fish and to allow employees to fish on a catch and release basis. Under consideration is the expansion of the dam to incorporate an adjacent site. In time a deck and covered area may be constructed so that mine personnel can hold workshops and conferences at the dam.
Closure
Closure plans are in place at all operations as required in terms of the new EMPs. The closure plan for Durban Roodepoort Deep (DRD) mine is currently being updated and the rehabilitation of surface areas continues with the goal of achieving closure.
The closure liabilities associated with environmental issues for each operation are assessed on an annual basis. The amounts, calculated according to the official Department of Mineral Resources (DMR) guidelines as at June 2010, are set out in the table below.
| Operation | Closure liabilities | Trust funds | ||
|---|---|---|---|---|
| 2010 R | 2009 R | 2010 R | 2009 R | |
| Blyvoor | 71 564 111 | 67 204 644 | 31 846 177 | 30 519 947 |
| Crown | 132 122 114 | 122 175 819 | 52 286 687 | 47 350 753 |
| Ergo | 230 003 476 | 218 270 210 | *** | *** |
| ERPM | 49 621 668 | 66 629 210 | 20 135 487 | 18 577 649 |
| DRD/Rand Leases* | - | 41 236 056 | 21 801 308 | 20 813 000 |
| West Wits/West Rands Consolidated** | 19 531 143 | 45 961 402 | 18 737 503 | 17 905 241 |
| Total | 502 842 513 | 561 477 341 | 144 807 162 | 135 166 590 |
* DRD/Rand Leases have been taken over by Mintails SA.
** The dumps and plant areas of these mines have been taken over by Mintails SA.
*** DRDGOLD is in the process of establishing guarantees and not a trust fund for this operation. These guarantees are not yet in place.
The operations have trust funds to meet the final closure liability and DRDGOLD makes annual contributions to the environmental trust fund in place at each operation (see table below). All the operations currently have shortfalls in terms of meeting their closure liabilities. DRDGOLD has proposed to the DMR that, apart from Blyvoor, these are covered through a financial guarantee. This proposal is under investigation. In the case of Blyvoor, the proposal is that revenue from the No 2 Shaft rock dump be ring-fenced. This would result in this operation’s liabilities being fully funded. To date, the DMR has not approved either of these funding proposals.
Biodiversity
No sites at Blyvoor, Crown or ERPM enjoy statutory protection or are considered to be areas of high biodiversity. The exception is the Ergo Daggafontein Tailings Complex (see case study in DRDGOLD’s Sustainable Development Report for 2009). There are certain instances where DRDGOLD applies for exemption with respect to alien vegetation. For example, blue gum trees are not indigenous but at some operations they are found near tailings dams where they absorb polluted water and act as a windbreak. In such a case, the company will prevent further spreading but will not eradicate the trees as their benefits outweigh any problems associated with their growth.
Blyvoor’s water plant will halve discharge of underground water
When the newly constructed water treatment plant at Blyvoor is commissioned within the next few months, this mine will halve the amount of underground water – between 8 and 13 megalitres a day – that it currently discharges into the Wonderfontein Spruit. It will also reduce the quantity of water it purchases from the Rand Water Board.
In total, Blyvoor pumps 25 megalitres of fissure water from 2 kilometres underground to surface every day. The mine uses about 6 megalitres of this water for processing purposes in the gold plant, 4 to 5 megalitres are pumped back underground for cooling purposes, and some water is used for vegetation. Once the water plant, which is situated at No 4 Shaft, becomes operational, about 5 megalitres of the remaining underground water will be treated to potable standards for use on mine property.
Blyvoor Engineering Manager Chris Sealy-Fisher says that the water will go through two processes in the plant: ultra filtration (UF) and reverse osmosis. “UF removes all the bacteria and a large portion of the solids in suspension. Reverse osmosis removes the dissolved salts, for example, sulphates. This water will then be used by Blyvoor village,” he explains.
A contracting company, Maano Water, installed and paid for the plant, which has a capital value of R10 million. Blyvoor will pay for the processing of the water, making the cost of this water more or less the same as that currently paid by the mine for water supplied by the Rand Water Board. A major boon for Blyvoor is that a five-year contract has been signed with Maano Water for the supply of water at a fixed cost. The contract will be renegotiated after that.
Sealy-Fisher sums up the benefits of the water plant: “In the first place we’ll be wasting far less underground water. Secondly, we’ll be putting less partially contaminated water into the Wonderfontein Spruit. Thirdly, we’ll be saving money as water from the Rand Water Board can be expected to become more expensive in the years ahead.”
He sees this type of recycling initiative being replicated elsewhere.“Water is a scarce resource and the country will have to start utilising all the water that is available,” he predicts.
It is possible that the water plant may be extended in the future to provide water for Doornfontein Village. If this happens, Sealy- Fisher says, the discharge of water into the Wonderfontein Spruit will be “very limited indeed”.
DRDGOLD clads Ergo’s 791-hectare Brakpan Tailings Dam to suppress dust and prevent erosion
Dust is being suppressed at Ergo’s 791-hectare Brakpan Tailings Dam through a three-and-a-half year project to clad the side slopes. It is expected to be completed in about 18 months’ time.
The Manager of Environmental Services at Ergo and Crown, Louis Kleynhans, says that there are a number of steps to the process. The first is to excavate dolorite – the substance used for cladding – from the Withok footprint (the area to the south of the tailings dam). However, before cladding can start, the side slopes have to be profiled to between 12° and 15°. Once the right shape has been achieved, the dolorite is placed on the side slopes at a thickness of 300 millimetres and, in order to minimise erosion, stormwater chutes or channels are installed at intervals of 200 metres. These chutes carry water down to solution trenches which flow into collector dams and from there the water is pumped back into the operation’s water circuit.
The chutes are protected from erosion by a 2-metre wide vegetation strip on either side.At every chute’s discharge point, where water flows over the access road, a concrete slab is cast to prevent soil erosion. Grass species such as Eragrostis curvula, Cynodon dactylon, Chloris gayana and Digitaria eriantha are sown where required.
Kleynhans explains the reasons for using dolorite. “It seals sand effectively and once it has weathered, it is conducive to plant growth, thus preventing windblown dust and soil erosion.”
Cladding is not the only dust suppression measure being taken at the Brakpan Tailings Dam. Made of shade cloth, 1-metre-high nets have been set up in rows, 10 metres apart, to act as wind barriers in certain areas on the top of the dam.
It is estimated that the total cost of all the remediation work being carried out on the dam will be R84 million. The costs incurred to date amount to R54 million, with 113 hectares having been completed.
More commonly, DRDGOLD employs ridge ploughing rather than cladding to suppress dust on the top of dormant tailings dams. Kleynhans discusses how this works. “The prevailing wind in Johannesburg comes from the north-west and what we do is to plough ridges against the prevailing wind. The wind then fills up these ridges with windblown sand which oxidises, making it good for vegetation.”
During the year under review, 50 metres of ridge ploughing were undertaken at the Elsburg No 3 Tailings Dam and 50 metres of ridges were vegetated. Ridges were also ploughed at the Elsburg No 4 and the Rooikraal tailings dams.
Another source of dust at Crown and Ergo is the road system. Vehicles churn up dust on the operations’ dirt roads during the dry winter season and water tankers are used to spray water on the haul roads throughout these months. “We spray at least 2 000 litres of water a day,” says Kleynhans, making the point that it is processed and not fresh water that is used. In certain areas dust bonding agents are also used.
DRDGOLD Sustainable Development Report 2010