This work will include plant design, capital cost and operating cost estimation, process and non-process infrastructure evaluation.
Managing director Alex Molyneux said, “The recently published PFS for Abra demonstrated outstanding investment returns and we’re keen to see it engineered to the highest standards so we’re in a strong position to commence construction next year.
“In this regard we’re very pleased to have GR Engineering onboard in a key role.”
The DFS is targeted to be complete in mid-2019 with Galena targeting the start of construction in 2019, initial production in 2021 and the first full-year of steady-state commercial production in 2022.
A number of key items in the PFS have been completed to DFS-level including geotechnical drilling, metallurgical test work, environmental studies and reports, water supply analysis, hydrogeology, underground mine designs and infrastructure design.
Impressive track record
In the past 11 years, GR Engineering has completed more than 40 design and construction projects and over 160 feasibility studies including a number of ‘flagship’ Australian base metals projects.
Its managing director Geoff Jones said, “GR Engineering was involved in the Abra PFS and we are pleased to have been engaged to deliver key aspects of the DFS and to assist Galena realise the significant potential of the Abra Base Metals Project.”
Key technical appointment
Galena has also appointed a fulltime metallurgy and study manager to lead the internal DFS work under the guidance of chief operating officer Troy Flannery.
The company intends adding further experts to its technical and operating team in the lead-up to project construction.
The storage area for Abra drill core.
Start of the DFS follows the completion last month of the PFS.
The PFS envisages a 1.2 million tonne per annum throughput underground mine and conventional flotation concentrator.
This would produce a high-grade, high-value lead-silver concentrate containing 91,000 tonnes of lead and 760,000 ounces of silver annually over a 14-year mine life.
Galena said economic outcomes from the PFS were outstanding, with pre-tax net present value of $528 million, calculated at an 8% discount rate, and an internal rate of return of 50%.
Future work program
While work advances on then DFS, Galena plans to progress a number of value-adding milestone workstreams in parallel, including:
Abra’s current resource totals 36.7 million tonnes at 7.3% lead and 18 g/t silver, and within this is a probable ore reserve of 10.5 million tonnes at 8.1% lead and 20 g/t silver.