The next step was securing finance and becoming a producer in Nova Scotia within a year of gaining funding, the company said.
ScoZinc said the updated PFS - which also included updated commodity prices, treatment charges and exchange rates - put initial capex at C$30.6 million, after-tax NPV8 at $128 million and IRR at 65% for a 14.3-year mine producing a five-year annual average of 35 million pounds of zinc and 15Mlb of lead.
It estimated gypsum reserves mined of 5.18 million tonnes over the life of mine.
ScoZinc had announced a non-binding offtake agreement for Scotia's life of mine gypsum supply on November 1.
The PFS released in July 2020 had outlined initial capex of $30.8 million, an after-tax NPV8 of $115 million and an IRR of 49%, for a 14-year mine at the same zinc and lead production rates.
President and CEO Mark Haywood described the updated PFS economics as 12% more robust than in the 2020 study.
"Importantly, the PFS shows that commercial zinc and lead concentrate and gypsum production can be achieved within 9 to 12 months of project financing of approximately $30 million, with a resulting average annual cash flow of $18 million," he said.
"The extensive facilities already in place on site, combined with the short pre-stripping period, enable the Scotia mine to potentially demonstrate a free cash flow of $19 million in the first year of commercial production."
The study's base case used both short-term price assumptions of US$1.40/lb zinc, $0.94/lb lead and $8.60/t gypsum, plus long-term assumptions of $1.20/lb, $1.05/lb and $8.60/t respectively.
ScoZinc had a working capital deficiency of almost C$600,000 at June 30.
It had been planning a business combination with Fancamp Exploration but this idea was scrapped in September, with Fancamp instead last month investing $1.3 million and converting a $250,000 debt to shares to become a cornerstone investor.
ScoZinc shares (TSXV: SZM) have spanned 45-80c over the past year and closed down 4% to 72c yesterday, valuing it at $12.8 million (US$10.1 million).
