Adaptation Actions for a Changing Arctic: Perspectives from the Barents Area

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Adaptation Actions for a Changing Arctic: Perspectives from the Barents Area

Box 6.5 Climate change impacts on mining: Kittilä gold mine, Finland Agnico-Eagle Finland Ltd operates a gold mine in Kittilä municipality in Finnish Lapland. The mine was chosen for this case study owing to its geological, economic and environmental significance.The areal water balancemodelling and global climate change scenarios were constructed to study the likely future changes in hydrology in the mine area and to assess possible consequences and necessary adaptation actions. Modelling was undertaken using SYKE’s Watershed Simulation and Forecasting System (WSFS; Vehviläinen et al., 2005) based on the average scenario of 19 global climatemodels (Christensen et al., 2007; Kirtman et al., 2013). Short- term (2010–2039) and long-term (2040–2069) changes in climate parameters were assessed against a reference period (1971–2000).

may require more vigilant monitoring, especially in relation to controlling the timing and amount of effluent discharge from the mine. Environmental limits for the Kittilä mine are based on both the concentration of harmful substances in the treated wastewater as well as the amount of water released in relation to flow in the River Seurujoki. As a result, supplementary measures on wastewater discharge might be needed in the future particularly during the summer if the low flow periods increase significantly. The changes in the areal hydrology as a consequence of climate change require the mining operators to redesign the water management in the mine area. In mining operations, increased seasonal variation in hydrology may result in: dust formation; runoff from waste rock areas and possible acid mine drainage; pumping of drainage waters and storage of waters in the area; changes in the quality and quantity of wastewaters to be purified; challenges for wastewater treatment – flexibility and capacity; a need to redesign the management of surface waters and groundwater so as to prevent groundwater contamination; and extreme precipitation that may lead to potential overflow of tailings ponds, cause flooding and road erosion as well as increased risk of environmental contamination.

The climate scenarios show significant average change in long-term temperature (3.18°C) and precipitation (11.5%). Changes in temperature, precipitation, evaporation, humidity, wind, run off, snow cover, river flow and groundwater level are likely to impact mining operations. Warming in the winter period was identified as the most significant change affecting the water balance of the mine. Warming will affect snow conditions and melting of snow in the area. Instead of one clear melting period in the spring the melting is likely to take place gradually during a longer period of time.As a result, seasonal patterns in river flow are likely to change. Figure 6.15 shows the projected changes in the flow patterns for River Seurujoki. River flowmay peak at different times and the first peak flowmight become earlier. Low flows

Kittilä

Discharge, m 3 /s

Finland

45

Sweden

Reference period 1971-2000 Short-term changes 2010-2039 Long-term changes 2040-2069

Norway

40

35

Maximum discharge Average discharge Minimum discharge

30

25

20

15

10

5

0

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Figure 6.15 Observed daily discharge in River Seurujoki in Finnish Lapland for the period 1971–2000 and as projected over the short term (2010–2039) and long term (2040–2069). The data show maximum, average and minimum discharge (based on unpublished SYKE data). The inset shows the position of the Kittilä mine – the treated waste water from the Kittilä gold mine is discharged into the River Seurujoki.