Nevada Copper’s board has made the decision to proceed to full construction at the Pumpkin Hollow project in Nevada, US, paving the way for its contractors to start working on the new underground mine.
The construction sign off follows a recently completed C$108.5 million ($84 million) public offering of Nevada Copper common shares and pre-construction activities that have been ongoing since May 2018.
Nevada Copper said the transition from pre-construction works to full-scale construction was expected to commence shortly. The 2017 prefeasibility study plan outlined a 5,000 t/d underground project able to produce some 50 MIb/y (22,680 t/y) of copper over a 13.5-year life at all-in sustaining costs of $1.96/Ib, while also laying the foundations for a larger integrated project that includes openpit development and could increase throughput to 70,000 t/d.
In connection with the construction decision, Nevada Copper has awarded a mining contract for shaft sinking and underground mine development work at Pumpkin Hollow to Cementation USA. The contractor has previously worked on the project, having sunk the existing production shaft (down to 579 m) and developed hoist infrastructure in advance of commencement of underground construction activities.
Sedgman USA, a member of the CIMIC Group, has received the engineering, procurement and construction contract for the surface plant and infrastructure at Pumpkin Hollow. The fixed price $118 million contract follows several months of a detailed engineering and design programme conducted by Sedgman incorporating a number of significant improvements to the prefeasibility study for the $197 million underground project.
These improvements are all part of Nevada Copper’s latest review and detailed design for the underground project, which, it says, has led to a number of project optimisations and operational de-risking measures being incorporated in the mine design.
This includes a centralised mine design, providing greater operational efficiency for the underground mine, and construction of a ventilation shaft via blind sink, which provides a lower-risk method to support schedule compliance and further enhances optionality for future operations, the company said.
“Further project enhancements continue to be reviewed by Nevada Copper, including debottlenecking to subsequently increase production throughput and the potential for decline access to the E2 orebody.”
Nevada Copper anticipates first concentrate production from Pumpkin Hollow in the December quarter of 2019.