Endomines is assessing an expansion of the Pampalo gold mine in Ilomantsi, eastern Finland. The plans include deeper underground mining, a larger open pit and a pipeline for withdrawing raw water from Lake Hattujärvi. The mine’s proximity to the Koitajoki Natura 2000 site makes water management and tailings storage central environmental issues.
An environmental impact assessment has begun for the proposed continuation and expansion of operations at the Pampalo gold mine. The mine is located at Hattuvaara in the municipality of Ilomantsi, close to the Russian border in Finland’s North Karelia region.
According to Finnish public broadcaster Yle, mining company Endomines has prepared 3 alternatives for the future of the operation. The first would allow mining to continue without the proposed expansion. The other 2 would involve deepening and enlarging both the underground mine and the open pit.
The expansion alternatives also include the construction of a transfer pipeline to Lake Hattujärvi. The pipeline would allow Endomines to withdraw raw water needed by the mine’s processing plant.
The proposal could give Lake Hattujärvi a more important role in the mine’s water supply. The municipality of Ilomantsi therefore wants the environmental assessment to explain clearly how the withdrawal could affect the lake, its water levels and the surrounding natural environment.
Natura 2000 site just over 1 kilometre away
The distance between the mining area and the protected Koitajoki Natura 2000 site is approximately 1.2 kilometres. This proximity means that possible effects on waterways, habitats and protected natural values must be investigated before any new permits can be granted.
Endomines considers that the proposed expansion would not weaken the natural values of the Koitajoki protected area. However, the company’s assessment will be examined as part of the formal environmental impact assessment process, in which authorities, the municipality, organisations and local residents can also submit their views.
An environmental impact assessment is not the same as an environmental permit. Its purpose is to identify and compare the possible effects of a project before the company submits its actual permit applications.
The assessment is expected to cover potential impacts on surface water, groundwater, ecosystems, landscapes, human health, traffic and nearby activities. It must also describe measures that could prevent or limit environmental damage.
At Pampalo, the relationship between raw-water withdrawal, the mine’s process water and the management of mining waste will be particularly important. The assessment must also consider temporary disruptions, extreme rainfall and possible failures in the water-management system.
Two alternatives for storing mine tailings
The 2 expansion alternatives differ mainly in how the mine tailings would be stored. Tailings are the finely ground waste material left after gold and other recoverable substances have been separated from the mined ore.
One alternative is based on wet storage, in which the tailings are deposited together with water. This approach can reduce dust formation, but creates risks related to seepage, containment structures and possible overflows of wastewater or process water.
The second alternative involves dry stacking. Under this method, the tailings are dewatered before being deposited at the site. Dry stacking can reduce the amount of free water in the storage area, but it brings other environmental risks.
During dry periods, dust may spread into the surrounding environment. Heavy rainfall can, in turn, cause erosion and wash material away from the tailings stack.
The Ilomantsi municipal executive is expected to issue an opinion on the environmental assessment programme. According to the proposal prepared for the municipality, particular attention should be paid to the planned withdrawal of water from Lake Hattujärvi and to a clear comparison of the environmental risks associated with wet and dry tailings storage.
The choice of storage method will affect more than the mine’s day-to-day operation. The tailings facility must remain stable after mining eventually ends. The assessment therefore also needs to consider long-term water treatment, rehabilitation, environmental monitoring and financial responsibility.
Public consultation may shape further studies
Residents, landowners, associations and other interested parties can comment on how the environmental impact assessment should be conducted until 26 August 2026. The consultation allows the public to identify local conditions and risks that may require closer investigation.
The consultation does not determine whether the expansion will be approved. However, the comments submitted can affect which studies are carried out, which alternatives are compared and how the environmental risks are presented.
The final environmental impact assessment report, bringing together the results of the studies, is scheduled to be made publicly available in March 2027. The responsible permitting and supervisory authority is then expected to issue its reasoned conclusion by summer 2027.
The findings will form an important part of the documentation when Endomines later applies for an environmental permit and other approvals needed for the expansion. The authorities may impose conditions covering water withdrawal, discharges, waste management, monitoring programmes and rehabilitation of the mining area.
Endomines is simultaneously conducting another environmental impact assessment in the region. That process concerns plans to bring additional ore deposits along the company’s so-called Southern Gold Line into production.
Together, the projects could influence the future scale of Endomines’ mining operations in Ilomantsi and determine how ore is supplied to the Pampalo processing plant.
The plans also illustrate a common conflict surrounding mine expansions. Continued production can attract investment and support employment, but it also creates long-term responsibilities for water supply, tailings management and the protection of nearby natural areas.
Sources: Yle, Endomines and information published by Finland’s environmental administration concerning the environmental impact assessment of the Pampalo mine.
