Since its closure, the Viscaria mine has filled with around six million cubic metres of water, which over the years has dissolved substances from the ore body. To safely and sustainably dewater the mine, we have built a new water treatment facility, an investment of approximately SEK 500 million and one of the largest environmental initiatives in the Swedish mining industry.
The dewatering of the Viscaria mine
Before mining at Viscaria can resume, the water that has accumulated over many years in the former mine workings must be pumped out. Draining the mine is a crucial step in the reopening of Viscaria and is carried out with the greatest care for both people and the environment.
The underground facility comprises around 65 kilometres of existing tunnels, which are being gradually emptied of groundwater. As the water level lowers, the infrastructure can be rehabilitated and inspected, ensuring that preparations for future production can begin safely.
At present, untreated groundwater from the former mine flows directly into the recipient, which is normal for closed mines. Once dewatering begins, the water will instead be collected and directed to Viscaria’s new, modern water treatment plant, where it will be purified through sand filtration and ion exchange before being returned to nature with significantly reduced levels of metals and other substances.
Draining the mine is therefore not only a technical prerequisite for accessing the valuable mineral resources in the rock, but also a demonstration of how responsible mining can be put into practice with control, accountability and respect for the surrounding environment in the Kiruna area.
WTP 1000 – Water treatment of up to 1,000 m³ per hour
Viscaria’s water treatment plant, WTP 1000, is a SEK 500 million investment and one of the largest undertakings in the project’s first phase. The facility can treat up to 1,000 cubic metres of water per hour and has been developed to meet future requirements for efficient and sustainable water management within the mining industry.
Treatment technology – Steps 1 and 2
Water from the mine is treated in several stages to ensure the highest possible quality. It first passes through sand filters that remove particles and iron. It then flows through ion exchange filters that capture metals such as copper, zinc, cobalt and uranium. The result is water that becomes cleaner than drinking water, so pure that we will be able to produce our own drinking water from the process.
The treatment technology has been developed together with the Finnish company Teollisuuden Vesi and has the capacity to treat up to 1,000 cubic metres of water per hour. The system removes between 95 and 99 percent of metals before the water is returned to the Torne River. The work has been recognised by the County Administrative Board of Norrbotten as a potential new standard for future water treatment within the mining industry.
Drinking water production – Step 3
Viscaria’s water treatment plant is designed to deliver water of exceptionally high quality. Through an additional treatment stage, the water becomes both chemically and biologically drinkable. It will therefore be used as drinking water within our operations at Viscaria, clearly demonstrating how far the technology has advanced – from mine water to a complete cycle of clean water.
This technology enables a circular and sustainable approach to water management across our entire operation, where every drop is utilised with care and precision.
Regeneration – Step 4
When the ion exchange material has been used for some time, its treatment efficiency gradually decreases and the material needs to be cleaned to regain its full capacity. This is done by washing it with a saline solution and hydrochloric acid, chemicals that are recirculated in the process so they can be reused.
The washed sludge is dewatered in a filter press so that it can be deposited in a landfill for hazardous waste. In the future, there is also potential to extract other substances from the sludge.
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1000 m3
Water treatment capacity/hour
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95-99 %
Treatment effect of Cu, Zn och U
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The treatment results in a significant reduction in the outflow of metals:
Zn 4 tonnes→ 4 kg/year
U 0.3 tonnes→ 2 kg/year
Our collaborations within the project
The development of Viscaria’s water treatment plant has taken place in close collaboration with the Finnish company Teollisuuden Vesi, one of the leading players in industrial water treatment in the Nordic region. Together we have developed a unique technical solution that combines proven process expertise with new, innovative technology, tailored to Viscaria’s specific conditions.
Teollisuuden Vesi Oy (Industrial Water Ltd) is a Finnish company based in Mäntsälä, specializing in water treatment for both industrial and municipal needs. With extensive experience and expertise in water treatment unit processes and process microbiology, they develop sustainable solutions for the purification, recycling, and treatment of water and wastewater from system upgrades and troubleshooting to the design, construction, and operation of complete treatment facilities. Teollisuuden Vesi was responsible for the design and delivery of our water treatment plant, and their expertise has been crucial in establishing efficient processes and ensuring high-quality purification. Thanks to their work, we now operate a modern and reliable water treatment facility that guarantees clean water today and for the future.
Collaborations in the construction phase
The construction of Viscaria’s water treatment plant is being carried out in close collaboration with several leading contractors and specialists within their respective fields.
Collaboration for the dewatering of the Viscaria mine
Orefields Raise Boring AB is a Swedish specialist company in drilling and underground technology, based in Kiruna. Since the company was founded in 2010, it has developed advanced solutions for mining and infrastructure projects, with a focus on raise boring, downreaming, media hole drilling, engineering, and preparatory work. The company is particularly committed to working in complex and demanding environments where technical expertise and safety are paramount.
Timelapse WTP
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Our long-term environmental responsibility
As part of our long-term commitment, we have undertaken to operate the water treatment plant for at least 30 years after mining activities have ended. In this way, we can ensure that the water remains clean and that both people and nature continue to benefit from our efforts over time. To monitor the process, we continuously measure the water discharged from the facility and carry out additional sampling at several locations in the recipient. These checks form part of our environmental control programme.
