This compares with capex of $93 million estimated in a prefeasibility study 12 months ago, although the new feasibility study includes a water treatment plant to reduce the operation's water intensity.
Both studies planned an 86% increase in mill throughput from 0.7 million tonnes per annum to 1.3Mtpa, with the FS anticipating slightly higher average annual zinc production of 135 million pounds.
Trevali (TSX: TV) is aiming to produce 330-355Mlb this year from its four mines in Namibia, Burkina Faso, Canada and Peru.
Commercial production at RP2.0, which was slated for the second half of 2023 in the PFS, is now expected mid-2024 assuming a positive investment decision.
After-tax NPV8 was put at $156 million, free cash flow at $290 million, IRR at 58% and the payback period at 4.6 years.
President and CEO Ricus Grimbeek said the new study reaffirmed robust project economics and reduced carbon and water intensity.
"The RP2.0 project will modernise and expand the 50-year-old mine, increasing throughput by 86% and enabling the operation to increase production at a significantly lower operating cost, all while working more safely and reducing our environmental footprint," he said.
All-in sustaining costs were estimated at 67c/lb, compared with Rosh Pinah's 2021 guidance of 95-99c/lb, which was revised upwards this month from 85-90c/lb.
Grimbeek said Trevali had held productive discussions with its existing lending syndicate as well as numerous financial institutions on securing project debt financing, to minimise equity dilution.
Canaccord Genuity analysts, who lowered Trevali's target price, believed the capex could be funded from cash on hand and consolidated operating cash flow.
Trevali had reduced its net debt position from $109 million mid-year to $92.4 million at July 31.
Analyst Dalton Baretto said the FS was broadly in line with the PFS, with the key differences being a 10% increase in reverse tonnage and 19% increase in capex.
"In the short-term (2022 and 2023), we see a far more dramatic impact to our estimates, given a lower grade profile and higher operating costs over the construction period," he said.
"Our EBITDA estimates for 2022 and 2023 have declined by 13% and 39%, respectively, with the 2023 impact being magnified due to the loss of production from Santander and Caribou that year."
Canaccord reduced its target price from C25c per share to 20c but maintained a hold rating.
Trevali shares lost 5% or 1c yesterday to close at 18.5c, capitalising it at $183 million (US$ million).
