Chile's environmental watchdog has pressed charges against Sierra Gorda SCM, firm jointly owned by Poland's KGHM Polska Miedz and Japan's Sumitomo Metal Mining, saying it was found guilty of committing nine environmental infractions.
The fine would add pressure to KGHM, also the world's largest silver miner, which flagged last month a record $1 billion in write-downs on key foreign assets, including the Sierra Gorda mine in Chile, due to plunging metals prices.
KGHM gained control of Sierra Gorda in 2011 when it bought Canadian rival Quadra FNX for $2.07 billion (Cdn$2.87 billion), the largest ever foreign acquisition by a Polish company. The mine launched commercial production only last year.
In January Sierra Gorda's co-owner, Japan's Sumitomo , said it cut its profit forecast due to the investment loss at the mine.
According to Sumitomo, Sierra Gorda produced about 85,000 tonnes of copper concentrate in 2015 and aims to reach full utilization by the end of June.