Trevali reports strategic review of Caribou mine production

Press Release

Maintains consolidated 2018 zinc production guidance

VANCOUVER, British Columbia, Oct. 22, 2018 — Trevali Mining Corporation (“Trevali” or the “Company”) (TSX: TV; BVL: TV; OTCQX: TREVF; Frankfurt: 4TI) reports a downgrade of the 2018 production guidance for the Caribou mine due to challenging rock mass conditions. Increased zinc production from Perkoa operations is expected to partially offset metal losses. The Company reiterates it remains on track to achieve its 2018 consolidated zinc production guidance.

D ETAIL
The Caribou Mine was well positioned after the second quarter 2018 to achieve is target production in 2018. As part of an ongoing technical review, several key operational changes were required to ensure the safety of employees, equipment and to maintain production targets in the long term (2019+) due to challenging hanging wall rock mass conditions. Specifically, changes to the geotechnical control management were required, primarily the move to Cemented Rock Fill from unconsolidated fill. These were implemented during Q3 and impacted production, however site retained the ability to achieve the lower end of 2018 production guidance through increased Q4 production.

However, during early to mid-October adverse conditions were experienced in two mining zones resulting in the cessation of retreat mining and the subsequent loss of some production from the remaining 2018 mine plan. Further external engineering studies are ongoing and in order to increase mining flexibility, Caribou management have strategically slowed the mining rate in order to accelerate mine development in Q4-2018 through Q1-2019 to build more optionality and stability in the mine to deliver safe, strong and reliable results in 2019. Consequently, 2018 zinc and lead production will be adversely affected, and guidance has been revised downwards. 2018 silver production guidance remains unchanged.

Table 1 : Revised production guidance for Caribou mine.

	2018 Zn Production (payable)	2018 Pb Production (payable)	2018 Ag Production (payable)	Operating Cost (per tonne)
Caribou – revised	70-75 million lbs. (31,750-34,000 tonnes)	23.0-25.0 million lbs. (10,450-11,350 tonnes)	627,000-658,000 ozs.	US$63-69
Caribou – original	86-90 million lbs. (39,000-40,850 tonnes)	27.1-28.4 million lbs. (12,300-12,900 tonnes)	627,000-658,000 ozs.	US$55-61

“It is incredibly disappointing that the Caribou mine has been forced to slow down, however this was a necessary step in order to ensure the safety of our workforce and enhance the long-term economics of the mine,” stated Dr. Mark Cruise, Trevali’s President and CEO. “This strategic direction was made with a view of establishing a stronger foundation for the operation to deliver on expectations in 2019 and beyond.”
The Santander and Rosh Pinah mines remain on track to deliver production guidance with the Perkoa mine presently expected to exceed its guidance due to continued positive performance, helping offset the shortfall from the Caribou mine. Trevali remains on track to deliver 2018 zinc payable metal production of more than 400 million pounds. Zinc sales during the third quarter, however, lagged production with concentrate inventory levels above target at both Perkoa and Rosh Pinah. Additional concentrate shipments are planned for the fourth quarter to reduce inventories and increase sales.

Qualified Person and Quality Control/Quality Assurance
EurGeol Dr. Mark D. Cruise, Trevali’s President and CEO, is a qualified person as defined by NI 43-101, have supervised the preparation of and have verified the scientific and technical information that forms the basis for this news release. Dr. Cruise is not independent of the Company as he is an officer, director and shareholder.

ABOUT TREVALI MINING CORPORATION
Trevali is a zinc-focused, base metals company with four mines: the wholly-owned Santander mine in Peru, the wholly-owned Caribou mine in the Bathurst Mining Camp of northern New Brunswick, the 90% owned Rosh Pinah mine in Namibia and the 90% owned Perkoa mine in Burkina Faso.

The shares of Trevali are listed on the TSX (symbol TV), the OTCQX (symbol TREVF), the Lima Stock Exchange (symbol TV), and the Frankfurt Exchange (symbol 4TI). For further details on Trevali, readers are referred to the Company’s website (www.trevali.com) and to Canadian regulatory filings on SEDAR at www.sedar.com.

On Behalf of the Board of Directors of
TREVALI MINING CORPORATION
“Mark D. Cruise” (signed)
Mark D. Cruise, President

Contact Information:
Steve Stakiw, Vice President – Investor Relations and Corporate Communications
Email: sstakiw@trevali.com
Phone: (604) 488-1661 / Direct: (604) 638-5623

IBF4