Harmony Gold Mining Company Limited (Harmony) is a gold mining specialist with a growing international copper footprint.
The company has embedded sustainable mining practices throughout its operations to ensure the company produces safe, profitable ounces and improve the company’s margins through operational excellence and value-accretive acquisitions. The company’s higher-quality ounces, Eva Copper Project and Tier 1 Wafi-Golpu Project position the company well to become a significant gold-cop...
Harmony Gold Mining Company Limited (Harmony) is a gold mining specialist with a growing international copper footprint.
The company has embedded sustainable mining practices throughout its operations to ensure the company produces safe, profitable ounces and improve the company’s margins through operational excellence and value-accretive acquisitions. The company’s higher-quality ounces, Eva Copper Project and Tier 1 Wafi-Golpu Project position the company well to become a significant gold-copper producer. Through the company’s secondary mining operations, the company is the largest producer of gold globally through the retreatment of old tailings dams across South Africa.
Strategy
Producing safe, profitable ounces and improving margins through operational excellence and value-accretive acquisitions is Harmony’s strategy, translating the company’s purpose into action.
Business Activities
The company’s business activities include exploration and acquisitions; development; mining and ore processing; sales and financial management; and stewardship and mine closure.
The company’s primary product is the gold the company produces and sells to the market.
South Africa – Underground Operations
The company’s underground mines are grouped by ‘high-grade’ operations consisting of Mponeng and Moab Khotsong and the company’s ‘optimised’ operations consisting of the remainder of the company’s underground operations.
Moab Khotsong is a deep-level mine near the towns of Orkney and Klerksdorp, some 180km south-west of Johannesburg. The mine, which began producing in 2003, was acquired from AngloGold Ashanti Limited in March 2018.
Mponeng is a deep-level mine near the town of Carletonville, some 90km south-west of Johannesburg. The mine, which began producing in 1986, was acquired from AngloGold Ashanti Limited in October 2020.
Tshepong North is a deep-level underground mining operation in the Free State, near the town of Welkom, some 250km from Johannesburg. Tshepong North is a mature underground operation that uses conventional undercut mining in the Basal Reef while the B Reef is exploited as a high-grade secondary reef. Ore mined is processed at the Harmony One plant, with gold recovered using the gold cyanide leaching process.
Tshepong South is located in the Free State, near the town of Welkom, some 250km from Johannesburg. Tshepong South exploits the Basal reef with the B Reef mined as a high-grade secondary reef and uses the conventional undercut and opencut mining method. Rock from Tshepong South is transported via a railveyor system to Nyala shaft, from where it is hoisted to surface. Mining is conducted at depths of 1 500m to 2 300m. Ore mined is processed at the Harmony One plant, with gold recovered using the gold cyanide leaching process.
Joel is a twin-shaft mining operation in the Free State, some 290km south-west of Johannesburg, on the southern edge of the Witwatersrand Basin.
Target 1 is an advanced, single-shaft, deep-level mine in the Free State, some 270km south-west of Johannesburg. It has a planned life-of-mine of five years.
Kusasalethu is a mature, deep-level mine 90km west of Johannesburg, near the border of Gauteng and North West provinces. The mine comprises twin vertical and twin sub-vertical shaft systems and uses conventional mining methods in a sequential grid layout. It exploits the Ventersdorp Contact Reef as its primary orebody. Ore mined is treated at the Mponeng plant.
Masimong is a deep-level mine in the Free State, near Welkom, some 260km from Johannesburg. The operation is close to the end of its mine life, with two years of mining left. Masimong is a mine that reflects the effectiveness of Harmony’s business model. The Masimong complex comprises two shafts with 5 shaft used as the operating shaft and 4 shaft for ventilation, pumping and a second escape outlet. Masimong exploits the Basal Reef and B Reef, using a conventional tabular narrow-reef stoping method. Mining is conducted at a depth of 1 650m to 2 010m below collar. Ore mined is processed at the nearby Harmony One plant.
Bambanani is a deep-level mine in the Free State, near Welkom and some 260km south of Johannesburg. It comprises two surface shafts, with the East shaft used to convey employees and West shaft used to hoist ore to the surface. Bambanani has been one of Harmony’s most successful and profitable mines.
South Africa – Surface Operations
Mine Waste Solutions is a tailings retreatment operation near Klerksdorp in the North West province. It reprocesses low-grade material from tailings storage facilities scattered across the Vaal River and Stilfontein area to reduce the tailings footprint. The operation was acquired from AngloGold Ashanti Limited in October 2020. Harmony's subsidiary, Chemwes Proprietary Limited, the owner of Mine Waste Solutions, has a contract with Franco-Nevada Barbados (Franco-Nevada) where Franco-Nevada is entitled to receive 25% of all the gold produced through Mine Waste Solutions.
Kalgold is a long-life, open-pit gold mine on the Kraaipan Greenstone Belt, 55km south-west of Mahikeng in North West province. Mining takes place from the A-zone pit, Watertank pit, Henry’s pit as well as Windmill pit. Mined ore is processed at the carbon-in-leach Kalgold plant.
Phoenix is a tailings retreatment operation in Virginia, Free State. It retreats tailings from Harmony’s tailings storage facilities in the Free State region to extract any residual gold, using the Saaiplaas plant. It is 100% owned by the black economic empowerment company, Tswelopele Beneficiation Operation Proprietary Limited, of which Harmony is a 77% shareholder.
Central Plant Reclamation is a tailings retreatment operation near Welkom in the Free State.
Savuka plant is situated near the town of Carletonville and was acquired from AngloGold Ashanti Limited in October 2020. The plant originally treated both waste rock and tailings but was converted to a tailings treatment facility in October 2021 when the milling section of the plant was decommissioned.
Production from processing surface rock dumps, situated across Harmony’s operations, depends entirely on the availability of spare mill capacity at the various operational plants. Waste and waste rock dump deliveries to Kusasalethu plant (near the border of Gauteng and North West provinces) supplement mining volumes to secure sufficient backfill to use as support in stoping areas. Waste rock dumps near Orkney (acquired with Moab Khotsong operations) are treated at the Noligwa and Mispah plants. Milling of waste rock dumps at the Doornkop plant in Gauteng began in FY18. Waste rock dumps and tailings facilities acquired with Mponeng are treated at Mponeng and Kusasalethu plants. Surface ore treated at Kopanang plant was unprofitable and closed during the first quarter of FY22. The plant is on care and maintenance.
Papua New Guinea – Opencast Operations
The Hidden Valley Mine is an open-pit gold and silver operation in Morobe Province, Papua New Guinea, some 210km north-west of Port Moresby. The mine is located at elevations of 1 700m to 2 800m above sea level in steep mountainous and forested terrain that receives around 3 000mm of rainfall per year. The major gold and silver deposits of Hidden Valley are in the Morobe Granodiorite of the Wau Graben.
Major Projects
The company has identified substantial opportunities in its existing portfolio through exploration and brownfield projects which will extend the life of some of the company’s larger and higher-grade assets, adding lower-risk, higher-margin ounces to Harmony’s portfolio.
The salient features of the company’s key projects are:
South Africa
Moab Khotsong – Zaaiplaats Project
The Zaaiplaats project was approved by the board for implementation in October 2021. The project scope is to mine the Zaaiplaats orebody situated below the current Moab Khotsong middle mine area from 101 level to 114 level. Three new declines and associated infrastructure must be developed, equipped and commissioned below 101 level to allow the safe and economic mining of the Zaaiplaats orebody.
Mponeng Extension (including TauTona VCR Pillar)
The project will extend the Mponeng LoM by exploiting the VCR and the CLR orebodies below current infrastructure. Mining of the VCR reef below infrastructure requires the extension of existing infrastructure from 126 level, both on the Eastern and on the Western side of the orebody. Mining of the CLR reef requires the extension of the existing infrastructure from 120 level.
MWS – Kareerand Expansion
Mine Waste Solutions (MWS) is a reclamation operation in the Stilfontein/Orkney area treating 2.2 million tonnes per month from historical tailings facilities through the MWS plant. The residue is deposited on the existing Kareerand tailings storage facility (TSF) by cycloning. The Kareerand TSF has a 560ha footprint and was sized to receive the reprocessed tailings from the MWS sources. The inclusion of additional sources into the MWS business in 2012 required additional deposition facilities. The authorisation of the Kareerand extension project increases the current footprint by 340ha and allows the combined complex to be operated to a height of 100 metres.
Doornkop 207L & 212L
The project extends the mining of the orebody at depth on 207 and 212 level. Both levels need to be developed, while the shaft infrastructure needs to be completed in order for each level to be able to handle the planned production. An ore handling system below the 212 level infrastructure needs to be developed. In order to provide adequate ventilation and cooling over the LoM, the DK1a Shaft will be converted into an intake shaft in conjunction with setting up a refrigeration plant.
Renewable Energy
In order to achieve the renewable energy targets as set out in the Harmony Energy Efficiency and Climate Change Strategy document, it became necessary to implement a number of renewable energy technologies, including self-built PV plants, wheeling of wind and solar renewable energy, as well as small scale solar photovoltaic (PV) plants. Phase 2 construction, with a capacity of 137MW has begun in FY25.
Papua New Guinea
Hidden Valley brownfield exploration
Kerimenge prospect – The Kerimenge prospect is located approximately 8km to the east of the Hidden Valley Mine. Drilling to support a prefeasibility study was completed during the year. Review of existing drill data commenced with the aim of developing a new Mineral Resource estimate. Kerimenge is a historic gold deposit outlined by previous explorers that contains components of refractory and free milling oxide gold mineralisation.
Hidden Valley life-of-mine extension
The Hidden Valley life-of-mine (LoM) extension project concept study/prefeasibility study considers the potential to convert both the 0.6Moz Au Kerimenge Mineral Resource and the 1.6Moz Au remaining in the Hidden Valley Mineral Resource outside the current LoM convert to a viable, low risk, high-margin mining operation. The project will assess the application of conventional carbon-in-leach and heap leach technologies for the Mineral Resources and investigate technologies to increase the tailings storage capacity, which is the current mine life constraint at Hidden Valley.
An extension of the mining lease and the amendment to the environmental permit will be required to continue operations beyond 2030.
Australia
Eva Copper Project
The Eva Copper Project is in a feasibility update phase. The project is located 75km north east of Cloncurry in the highly prospective Mt Isa inlier region and will involve mining native copper and copper sulphide ore from six open pits and processing it through a copper concentrator. The projected mine life is predicted to extend beyond 15 years, providing a stable platform for continued growth.
History
Harmony Gold Mining Company Limited was founded in 1950. The company was incorporated in South Africa in 1950.