Trevali implementing new Caribou underground mining fleet

VANCOUVER, BRITISH COLUMBIA--(Marketwired - May 11, 2017) - Trevali Mining Corporation ("Trevali" or the "Company") (TSX:TV)(LMA:TV)(OTCQX:TREVF)(FRANKFURT:4TI) announces it has received initial delivery of part of its new Sandvik underground mining fleet for the Caribou Zinc Mine in the Bathurst Mining Camp of northeastern New Brunswick. Components of the new fleet, specifically new haul trucks and loaders, have arrived as scheduled and are currently being transitioned into operations where they are expected to deliver higher availability and production performance upon integration (Figure 1).

To view "Figure 1: New Sandvik loaders and haul trucks getting delivered to Trevali's Caribou Zinc Mine in NB" accompanying this press release, please visit the following link: http://media3.marketwire.com/docs/1094389_Fig1.pdf

As part of a site-wide optimization initiative, the new underground mining fleet for the Caribou Zinc Mine is an approximately Cdn$20-million investment through a partnership with Sandvik Mining that will supply and maintain a full fleet of mining equipment for Caribou operations. This initiative and transition to owner-operated status is expected to deliver safer and more productive operational capabilities and significant savings in overall Caribou operating costs.

Currently there are three loaders and four TH540 trucks onsite at Caribou as part of this initial equipment delivery. Additional components of the new Sandvik underground mining fleet are scheduled to be delivered over the next several weeks. The project is currently approximately a Quarter ahead of schedule for full transition of mining activities by the end of Q2-2017.

Caribou Underground Resource Conversion and Expansion Drill Program Commences

Trevali also announces commencement of its 2017 underground diamond drilling program. Boart Longyear Canada have been awarded the 14,400-metre contract for underground diamond drilling services. The program is a follow up to the 14,000-metre 2016 drill program that targeted inferred and indicated resources on both the North and East limbs of the deposit.

The 2017 program will continue this effort below the current workings on both the North Limb and East Limb, with a concerted emphasis on the down-plunge area of the North Limb that shows the greatest potential for addition of inferred resources (Figures 2 & 3). The goal for the 2017 program is to upgrade a significant portion of inferred resources (approximately 2-2.5 million tonnes) to the indicated category. A portion of the 2017 program is also slated to further delineate and upgrade indicated resources into the measured category. The proposed Caribou underground drilling for 2017 is shown in the longitudinal section views below (Figures 2 & 3).

To view "Figure 2: Caribou Mine - North Limb 2017 underground drill program plan" accompanying this press release, please visit the following link: http://media3.marketwire.com/docs/1094389_Fig2.pdf

To view "Figure 3: Caribou Mine - East Limb 2017 underground drill program plan" accompanying this press release, please visit the following link: http://media3.marketwire.com/docs/1094389_Fig3.pdf

In addition to the Caribou underground drill program, a surface drill campaign is currently underway to test near-mine targets.

ABOUT TREVALI MINING CORPORATION

Trevali is a zinc-focused, base metals mining company with two commercially producing operations.

The Company is actively producing zinc and lead-silver concentrates from its 2,000-tonne-per-day Santander mine in Peru and its 3,000-tonne-per-day Caribou mine in the Bathurst Mining Camp of northern New Brunswick. Trevali also owns the Halfmile and Stratmat base metal deposits, located in New Brunswick, that are currently undergoing a Preliminary Economic Assessment reviewing their potential development. Additionally, the Company has entered into a definitive agreement with Glencore PLC to acquire a portfolio of zinc assets from Glencore, including an 80% interest in the Rosh Pinah mine in Namibia, a 90% interest in the Perkoa mine in Burkina Faso, an effective 39% interest in the Gergarub project in Namibia, an option to acquire 100% interest in the Heath Steele property in Canada and certain related exploration properties and assets.

The common 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, President

This news release contains "forward-looking statements" within the meaning of the United States private securities litigation reform act of 1995 and "forward-looking information" within the meaning of applicable Canadian securities legislation. Statements containing forward-looking information express, as at the date of this news release, the Company's plans, estimates, forecasts, projections, expectations, or beliefs as to future events or results and the Company does not intend, and does not assume any obligation to, update such statements containing the forward-looking information. Such forward-looking statements and information include, but are not limited to statements as to: the expected benefits of the proposed Transaction, the closing the Transaction,, including the anticipated timing thereof, the satisfaction of all conditions to closing the Transaction and the Offering including, without limitation, obtaining all necessary consents and approvals, the completion of the debt financing, the Company's plan to prepare a new PEA for its Halfmile and Stratmat properties, the accuracy of estimated mineral resources, anticipated results of future exploration, and forecast future metal prices, expectations that environmental, permitting, legal, title, taxation, socio-economic, political, marketing or other issues will not materially affect estimates of mineral resources. These statements reflect the Company's current views with respect to future events and are necessarily based upon a number of assumptions and estimates that, while considered reasonable by the Company, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies.

These statements reflect the Company's current views with respect to future events and are necessarily based upon a number of assumptions and estimates that, while considered reasonable by the company, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements contained in this news release and the Company has made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: fluctuations in spot and forward markets for silver, zinc, base metals and certain other commodities (such as natural gas, fuel oil and electricity); fluctuations in currency markets (such as the Canadian dollar and Peruvian sol versus the U.S. dollar); risks related to the technological and operational nature of the Company's business; changes in national and local government, legislation, taxation, controls or regulations and political or economic developments in Canada, the United States, Peru or other countries where the Company may carry on business in the future; risks and hazards associated with the business of mineral exploration, development and mining (including environmental hazards, industrial accidents, unusual or unexpected geological or structural formations, pressures, cave-ins and flooding); risks relating to the credit worthiness or financial condition of suppliers, refiners and other parties with whom the Company does business; inadequate insurance, or inability to obtain insurance, to cover these risks and hazards;
employee relations; relationships with and claims by local communities and indigenous populations; availability and increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development, including the risks of obtaining necessary licenses and permits and the presence of laws and regulations that may impose restrictions on mining; diminishing quantities or grades of mineral resources as properties are mined; global financial conditions; business opportunities that may be presented to, or pursued by, the Company; the Company's ability to complete and successfully integrate acquisitions and to mitigate other business combination risks; challenges to, or difficulty in maintaining, the Company's title to properties and continued ownership thereof; the actual results of current exploration activities, conclusions of economic evaluations, and changes in project parameters to deal with unanticipated economic or other factors; increased competition in the mining industry for properties, equipment, qualified personnel, and their costs. Investors are cautioned against attributing undue certainty or reliance on forward-looking statements. Although the Company has attempted to identify important factors that could cause actual results to differ materially, there may be other factors that cause results not to be as anticipated, estimated, described or intended. The Company does not intend, and does not assume any obligation, to update these forward-looking statements or information to reflect changes in assumptions or changes in circumstances or any other events affecting such statements or information, other than as required by applicable law.

Trevali's production plan at the Caribou Mine is based only on measured, indicated and inferred mineral resources, and not mineral reserves, and does not have demonstrated economic viability. Trevali's production plan at the Santander Mine is based only on measured, indicated and inferred mineral resources, and not mineral reserves, and does not have demonstrated economic viability. Inferred mineral resources are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves, and there is therefore no certainty that the conclusions of the production plans and Preliminary Economic Assessment (PEA) will be realized. Additionally, where Trevali discusses exploration/expansion potential, any potential quantity and grade is conceptual in nature and there has been insufficient exploration to define a mineral resource and it is uncertain if further exploration will result in the target being delineated as a mineral resource.

We advise US investors that while the terms "measured resources", "indicated resources" and "inferred resources" are recognized and required by Canadian regulations, the US Securities and Exchange Commission does not recognize these terms. US investors are cautioned not to assume that any part or all of the material in these categories will ever be converted into reserves.

This news release does not constitute an offer to sell or a solicitation of an offer to buy any of the securities in the United States. The securities described herein have not been and will not be registered under the United States Securities Act of 1933, as amended, or the securities laws of any state and may not be offered or sold within the United States, absent such registration or an applicable exemption from such registration requirements.

The TSX has not approved or disapproved of the contents of this news release.