Nevada Copper began sinking the underground production shaft for its Pumpkin Hollow copper project at Yerington, Nevada, in late February 2012. The 2,200-ft-deep, 24-ft-diameter shaft will provide access to Pumpkin Hollow’s East underground deposit.
At a groundbreaking ceremony for the shaft-sinking project, Nevada Copper President and CEO Giulio Bonifacio said, “This shaft will allow us to access the over 820 million lb of high-grade underground copper reserves in the East deposit defined in the feasibility study. The shaft will also provide us with detailed information on the geotechnical, geochemical and hydrological conditions that exist underground and will verify our mining and production assumptions. It will give us access to further extend and define the East underground resource from subsurface drill stations and will provide a platform for further exploration of the nearby JK34 zone.”
Project development at Pumpkin Hollow consists of a 7,500-st/d underground operation and a 60,000-st/d open-pit operation, feeding a single 67,500-st/d concentrator. In the first five years of operation, average annual production is projected at 274 million lb of copper, 53,000 oz of gold, and 1.1 million oz of silver. First production is targeted for mid-2015, with a current mine life of 18 years. Life-of-mine production of metal in concentrates is estimated at 3.83 billion lb of copper, 641,917 oz of gold, and 15.37 million oz of silver.
Based on drill data up to October 2010, proven and probable mineral reserves at Pumpkin Hollow total 4.29 billion lb of copper, 952,000 oz of gold, and 27.3 million oz of silver. Initial capital costs to develop the project are estimated at $1.04 billion, including contingencies and excluding working capital of $48.9 million. Life-of-mine site operating cash costs are estimated at $12.33/st of ore-milled. Life-of-mine copper production costs net of gold and silver credits are estimated at $1.43/lb of payable copper
A number of companies have expressed interest in the project and have been conducting due diligence while awaiting the feasibility study.
Detailed engineering and ordering of key long-lead-time mining and processing equipment for Pumpkin Hollow will start by mid-2012. Pre-stripping of the North open-pit deposit and construction of the mill and related facilities will occur in 2013–2014 once permits are obtained. Production is anticipated to begin in the second quarter of 2015.