NCC has been commissioned by LKAB to raise walls on two sections of the tailings dam at the Kiruna mine’s industrial site in 2023-2024. The contract includes foundation work on the dam toe of these two sections and raising the crest of the dams by six and two meters, respectively. Raising the crest will require significant excavation and filling work – approximately 300,000m³ of excavation and approximately 800,000m³ of filling. The height increases are being conducted at the rate required to meet the measured storage needs and at the rate permitted under the applicable environmental permit. NCC will also install a power supply for measuring wells and lay drainage pipes and soakaways.
“One prerequisite for the production of iron ore at the Kiruna mine is that we continuously safeguard the storage of ore tailings. For this to work, we must continually raise the walls of the tailings dam so it can store more ore tailings. To create the optimal conditions in terms of time and cost efficiency, we have now entered a collaboration with NCC to guarantee storage over the long term,” says Mattias Ejnestrand, advisor, project division LKAB.
When iron ore is mined, a large quantity of wet waste is created, or ore tailings, which are stored in tailing dams. These tailings storage facilities contain a tailings dam and a clarifying reservoir. The ore tailings are left to settle in the tailing dam while the water passes into the clarifying reservoir.
“NCC has built dams in the past and has long and solid experience from similar assignments around the Malmfälten mining district. We are proud and happy that LKAB has entrusted us with this task and look forward to initiating the partnership,” said Robert Nilsson, Production Manager at NCC Infrastructure in Kiruna.
The contract is a partnering agreement with an order value of approximately €14m and it will be registered among orders in the NCC Infrastructure business area in the third quarter of 2023. The project is scheduled for completion in autumn 2024.
