Quaterra Resources Inc. (TSXV:QTA) announced that it has started preparing a comprehensive prefeasibility study (PFS) for its MacArthur open-pit oxide-leach copper project. The asset is located in the northern area of the company’s property in Nevada’s Yerington copper district.
As quoted in the press release:
In November 2017, Quaterra engaged M3 Engineering & Technology Corporation (“M3”), of Tucson, Arizona, to review opportunities to optimize the near-term production potential at MacArthur as laid out in the 2012 Preliminary Economic Assessment (“2012 PEA” – please see press release dated May 23, 2012 at www.quaterra.com).
The 2012 PEA identified several areas for potential improvement, including additional metallurgical work and focused resource drilling. In addition, M3’s recent review indicates that it may be more economic to buy sulfuric acid in the market than to build an acid plant to process purchased sulfur. The acid plant represented $65.4 million or 28% of the total pre-production capital costs of $232.7 million in the 2012 PEA.
Following the review and final evaluation, the Company intends engaging M3 to complete a prefeasibility study in order to add more certainty to the economic potential of MacArthur with a view towards advancing the project toward development.
As part of the PFS, M3 and others will focus on:
- Updating the resource model and optimizing the mine plan.
- Reducing initial capital costs by eliminating the acid plant.
- Investigating ways to improve copper recovery by testing various crush sizes to replace the original plan to use Run-of-Mine (ROM) material. The new metallurgical test work program will help define the ultimate recovery, acid consumption, and leach cycle for ROM and crushed ore as well as optimal leach pad parameters. Bulk leach tests of copper oxide material are included in the test work plan.
- Evaluating the cost-recovery trade-offs of leaching ROM material compared with crushed material.