TORONTO (miningweekly.com) – Mexico-focused gold producer Goldgroup Mining on Thursday said that it had received an explosives permit from the Secretary of National Defense, which was the final permit necessary for full-scale operations at the company's 100%-owned Cerro Prieto openpit, heap leach gold mine in Sonora state, Mexico.

The explosives permit would allow Goldgroup, which started pouring gold from the project last month, to order and use explosives for mining purposes under military supervision.

The environmental-impact statement and the authorisation of change of land use for the project were previously granted.

"In commencing trial mining over the last three months we were restricted to bulldozer ripping. With the granting of the explosives permit, Goldgroup can now ramp up to full-scale mining at our mine,” Goldgroup chairperson and CEO Keith Piggott said.

He added that the tertiary crusher had been commissioned, which, owing to the a finer crush size, was expected to reduce the leach time for precious metals. “We now expect gold production to increase to a steady state as the heap leach pad builds,” he said.

The company stressed that it was not basing its production decision on a preliminary economic assessment demonstrating the potential viability of mineral resources, nor a feasibility study of mineral reserves demonstrating economic and technical viability at Cerro Prieto, and as a result there was increased uncertainty and multiple technical and economic risks associated with this production decision.

The Cerro Prieto project encompasses mineral concessions totalling about 7 000 ha and contains about 17.5 km of strike length of the mineralised structure hosting the current resource.

The company acquired the Cerro Prieto project last year through a $18-million deal in which it bought TSX-V-listed Oroco Resource Corporation.