A NIVA scientist asserts that a plan of action dating from 1992 has become obsolete and new initiatives are needed immediately to save a river in Sør-Trøndelag county. “Without implementing new measures it will be impossible to maintain the Orkla as the salmon-bearing river it is today,” says researcher Eigil Rune Iversen at NIVA.
The pollution situation at the Løkken Mining area in Meldal municipality was stabilized by measures implemented in 1992. These initiatives worked well for five years, but then emissions of iron started to mount, year by year. From 2005 the mines have also started polluting the watercourse with large amounts of copper. During these years pH values have remained far too low.
Løkken pollutes more than any other sulphide ore mines in Norway
Runoffs containing metals from the Løkken Mining area has affected water quality in the lower reaches of the Orkla and the Orkdalsfjord for over 100 years. During the 1940s metal pollution in the river spiked and the mining company was forced to pipe the highly acidic and metal-polluted mine water directly into the fjord to protect the river. In 1987 the mines were closed down after 333 years of operations.
Discharges of mine water were curbed in 1984 and the depleted Wallenberg Mine was filled with water by natural influx. It took eight years for the mine to fill up. Spillage of water from mine tailings and waste on the surface continued to be a big problem. The Norwegian Pollution Control Authority had reports on countermeasures prepared from 1988-1991. The objective was to limit spillage to less than 10 µg/l as the average maximum annual concentration of copper in the Orkla River at Vormstad.
NIVA is the Norwegian Institute for Water Research
Norsk institutt for vannforskning (NIVA)
The pollution situation at the Løkken Mining area in Meldal municipality was stabilized by measures implemented in 1992. These initiatives worked well for five years, but then emissions of iron started to mount, year by year. From 2005 the mines have also started polluting the watercourse with large amounts of copper. During these years pH values have remained far too low.
Løkken pollutes more than any other sulphide ore mines in Norway
Runoffs containing metals from the Løkken Mining area has affected water quality in the lower reaches of the Orkla and the Orkdalsfjord for over 100 years. During the 1940s metal pollution in the river spiked and the mining company was forced to pipe the highly acidic and metal-polluted mine water directly into the fjord to protect the river. In 1987 the mines were closed down after 333 years of operations.
Discharges of mine water were curbed in 1984 and the depleted Wallenberg Mine was filled with water by natural influx. It took eight years for the mine to fill up. Spillage of water from mine tailings and waste on the surface continued to be a big problem. The Norwegian Pollution Control Authority had reports on countermeasures prepared from 1988-1991. The objective was to limit spillage to less than 10 µg/l as the average maximum annual concentration of copper in the Orkla River at Vormstad.
NIVA is the Norwegian Institute for Water Research
Norsk institutt for vannforskning (NIVA)