Swedish mining firm Boliden plans to invest $530m (Skr5bn) on tailings dam works at its Aitik copper mine in northern Sweden, over the next two years.

The firm said that ongoing geotechnical investigations in the Aitik mine determined the requirement to eventually change to a new dam construction method to facilitate tailings’ long-term disposal.

Furthermore, the investigations showed that there is a need to strengthen the current dam construction to comply with the best international industry standards.

Boliden president and CEO Mikael Staffas said: “A high level of dam safety is always our top priority. The new direction naturally entails challenges in the short term, but it also creates long-term opportunities in Aitik and a clear direction for how the business can be developed going forward.”

Boliden expects the production to be unaffected at the northern Swedish open-pit mine as tailings could continue to be deposited in other parts of the pond.

The firm said in a statement: “The measures depend on environmental permits and other approvals, but work can be started prior to the permitting process.”

Boliden has identified areas with poorer soil conditions than previously estimated. This is in connection to ongoing geotechnical surveys for future dam heightening.

Subsequently, additional dam heightening and deposition of tailings against dams in these areas have been suspended.

Initially, the firm plans to strengthen the existing dam structures and move certain infrastructure over an estimated period of two years, following which dam heightenings and deposition would be resumed.

Located south of Gällivare in northern Sweden, the Aitik project is said to be one of the world’s most efficient open-pit copper mines.