A joint venture between engineering group Downer EDI and Ausenco has secured a contract for engineering, procurement and construction work at Oz Minerals’ Carrapateena copper gold mine project in South Australia.

Downer said the initial works are valued at around $100 million with the full contract value at $312 million.

Construction is scheduled to start at the end of the 2018 first quarter, Downer said in a statement on Monday.