Mine closure and reclamation

Our goal is to close the mine in a sustainable and exemplary manner. Closure and reclamation are carried out in such a way that the mining area becomes safe for people and the environment.

The regulations given in the environmental permit for closure and rehabilitation are followed. Pyhäsalmi Mine Oy also promotes projects that secure the region’s vitality after the end of mining operations.

CLOSURE AND AFTER-CARE MEASURES BY REGION

Underground mine

All machines, equipment, lighting, wires, pipes and other removable material will be removed from the underground mine, as far as it is technically possible and safe. In addition, the machines and equipment that may remain in the underground will be emptied of substances that cause the risk of environmental pollution.

If there will not be any further use of the underground mine, it fills with water. Before that shafts and passageways will be closed and ensured that there is no danger of collapse in the tunnels, which could cause subsidence of the ground surface. According to the groundwater modelling, it would take about 50 years for the mine to fill up naturally. Another option is to actively fill the underground mine.

Mine Site

Unnecessary buildings and structures will be demolished. Some of the buildings, such as the old hoist tower and the office building, are protected by Finnish Heritage Agency.

Open pit and quarry

The open pit and quarry will be kept fenced. If the underground mine fills with water also the open pit and quarry will be filled and form small but deep lakes. The quality of the water discharging from the quarries will be monitored and treated if needed.

Tailings Management Facility

The tailings ponds will be covered the way that it minimizes the entry of water and oxygen into the tailings, in order to prevent the formation of acid mine drainage. Pond C, which is currently water storage pond, will be constructed into a wetland.

Water treatment

In closure phase the seepage from the tailings ponds and surface water from the mine site are treated with lime precipitation in Actiflo® water treatment system. The waters are actively treated until the water quality requires it. The goal is to switch to passive treatment after the water quality has improved over the decades.