Shares of Capstone Copper (ASX:CSC) fell in recent Wednesday trade after it said in a late Tuesday statement that it had received the Declaracion de Impacto Ambiental environmental permit from the Atacama Regional Environmental Assessment Commission for its Mantoverde Optimized project, clearing a major regulatory hurdle for the planned expansion and increased copper production.

The company's shares were down 3% in recent trade.

The project is an expansion of the mine's sulfide concentrator, with a capital expenditure of $150 million to boost annual copper production, the company said.

The company received its environmental permit on schedule and has approved $20 million in orders for long lead items, with further updates on expansion and capital expenditures expected after formal project approval.

The Mantoverde mine in Chile's Atacama region, majority-owned by the company, recently started processing both oxide and sulfide reserves after completing a development project in 2023, the report added.