By Cecilia Jamasmie Polish miner KGHM (WSE:KGH), Europe’s second-largest copper producer, was given Monday environmental approval for a $2 billion expansion and upgrade of its flagship Sierra Gorda mine in northern Chile, 60 km south-west of the town of Calama. The state-controlled company grabbed the copper and molybdenum project in 2012, after completing the acquisition of Canadian rival Quadra FNX, in what was the largest-ever foreign acquisition by a Polish company. Upgrades are expected to extend the mine’s life by 21 years.