Integra said the project would yield an after-tax net present value of C$472 million at a 5% discount rate and a 43% after-tax internal rate of return at a $1,350/oz gold price and S$16.90/oz silver price following an initial capital expenditure of C$213 million (US$161 million).
"The economics presented for DeLamar are truly exceptional," said president and CEO George Salamis.
"Presenting a scenario for generating approximately C$697 million in cumulative after-tax cash flow, Integra's maiden DeLamar project PEA highlights a strong premise for an extraordinary, high-margin and long-life mining operation in a great tier one, infrastructure-rich mining jurisdiction like southwestern Idaho."
The study outlined all-in sustaining cash costs (AISC) of US$619/oz net of silver by-product or US$742/oz on a gold-equivalent co-product basis over its 10-year mine life. Mobile equipment financing could reduce the pre-production capex by up to C$34.8 million, assuming 20% cash down.
The PEA focused on resources amenable to heap leaching with a proposed 27,000 tonnes per day heap leach facility complemented by a 2,000 tonnes per day milling facility, sourcing oxide and transitional mineralisation from both the Florida Mountain and DeLamar deposits. A 2,000tpd mill would commence in year three to process unoxidised mineralisation from Florida Mountain. Production in years two to six would average 126,000oz gold and 1.8Moz silver for 148,000oz gold-equivalent.
The openpit mining operations would have a strip ratio of 1.09 and deliver a diluted head grade of 0.39 grams per tonne gold and 15.21g/t silver. Gold recovery is estimated to be 83% in heap-leaching and 90% in milling. Silver recoveries would be 34% in heap-leaching and 80% in milling.
Some 90% of DeLamar's estimated 2019 mineral resource estimate is in the measured and indicated categories backed by more than 2,500 drill holes. With a large portion of the unoxidised resource excluded from the PEA, and with other areas yet to drill test, Integra believes there is upside potential for oxide and transitional gold-silver mineralisation along the margins of the current DeLamar and Florida Mountain resources.
The DeLamar and Florida Mountain deposits host measured and indicated resources of 172.4 million tonnes grading 0.43g/t gold and 21g/t silver containing 2.4Moz gold and 116.5Moz silver. The company is undertaking resource expansion drilling to identify an expanded resource to support future studies including a pre-feasibility study which is due to commence in the coming months and be completed in the second semester of 2021.
Shares in Integra Resources (TSXV:ITR) are trading at C$1.30, valuing the company at $98 million.