During the third quarter this year, the mine released 54 kilogrammes of arsenic, 27 times annual amount allowed under current environmental regulations.
The country administrative board is now set a November 14th deadline for the company to come up with a plan for dealing with the poisonous discharge.
“We take this matter very seriously,” said Robert Erixon, an environmental protection official with the Västerbotten county board, to the Västerbottens-Kuriren newspaper.
No arsenic has leaked out into the surrounding area, which includes a nature preserve with wetlands as well as the Paubäcken basin, home to the rare freshwater pearl mussel.
Dragon Mining’s CEO Karl-Erik Marttala had no explanation for the leak, but said that the company is doing all that it can to solve the problem.