Falun Tisken

Runn

Dalalven

Figure 4.2. Map showing the main water courses in the Falun area, especially the receiving waters of the mine waste: the Gruvbacken Creek, River Faluan, Lake Tisken and Lake Runn, which empties into the great River Dalalven. Personal commuication, Lindestrom, 2002.

According to current estimates, a total of about 6 Mt of sulphur dioxide and 15 thousand tonnes of copper have been emitted to the atmosphere and between 0.5 and 1.0 Mt of copper, lead, zinc and cadmium have been discharged to the surrounding forest soils and watercourses. Therefore, the Falun area and the whole drainage basin of River Dalalven would be excellent objects for comprehensive studies of the fluxes of metals from mine waste to rivers and of the environmental impacts of metals such as copper and zinc as an input for environmental risk assessments. It would also be possible to utilise the Falun area for studies of whether, and how, nature has succeeded in adapting to often extreme environmental conditions, and to what degree nature has recovered after the emissions of pollutants have ceased.

The initiative to the ongoing "Falun Project" was taken soon after the Swedish Government appointed the "Dalalven Delegation" in 1988 and stipulated that it should devise a programme to purify River Dalalven within ten years. In the first report from this delegation, it was proposed to investigate measures for cleaning up the mining wastes, mainly in Falun and Garpenberg. Later on, in 1992, the Falun Project was launched. Its objective was to measure and reduce the metal discharges from mining wastes in Falun to an acceptable level during a time period of 15 years. The person in charge of the very comprehensive monitoring programmes in River Dalalven, including the lakes and watercourses linking the Falun Mine area with the main river (Lakes Tisken and Runn, River Faluan and the creek Gruvbacken) has, from the beginning been Lennart Lindestrom. He recently published a book giving a detailed account of "The Environmental History of the Falun Mine" (Lindestrom, 2003). Some of the highlights from this book that are particularly relevant for our understanding of the consequences of large-scale and long-term metal fluxes from non-ferrous mining wastes, especially the biological effects of this extremely strong and persistent metal exposure of the aquatic ecosystems in the receiving water bodies will be briefly summarized in this sub-chapter.

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