News Release

Trevali provides Caribou Zinc Mine commissioning update

September 9, 2015

Vancouver, British Columbia: Trevali Mining Corporation ("Trevali" or the "Company") (TSX: TV; BVL: TV; OTCQX: TREVF; Frankfurt: 4TI) provides an August mine and mill commissioning update for its Caribou Zinc Mine in the Bathurst Mining Camp of northern New Brunswick. A detailed description is provided below and progress highlights are as follows (Table 1):

Table 1: Caribou Mill - key commissioning & production statistics by month (figures rounded):

Mill Statistics MONTH
July August
Total Mill Throughput: 52,057 tonnes 77,149 tonnes
Average Daily Mill Throughput: 1,679 tpd 2,489 tpd
Zinc (Zn) conc. produced (WMT, approx.): 1,933 tonnes 5,016 tonnes
Average zinc concentrate grade %: 50% Zn 52% Zn
Average zinc recovery %: 39% 66%
Lead (Pb) - Silver (Ag) conc. produced (WMT, approx.): 491 tonnes 1,366 tonnes
Average lead-silver concentrate grade: 37% Pb & 598 g/t Ag 41% Pb & 607 g/t Ag
Average lead-silver recovery %: 19% Pb & 10% Ag 42% Pb & 20% Ag


Commissioning continued through the month of August with the primary focus on increasing mill circuit stability, achieving design capacity Zn and Pb recoveries, mill throughput and in the latter half of the month, with the arrival of partner Glencore's Australian IsaMill specialist, IsaMill optimization. The commissioning status of specific mill components is as follows:

Grinding / IsaMills -- Modifications to the IsaMill circuit occurred during the month and a variety of recommendations are currently being implemented including but not limited to optimal media sizing, improved pump-delivery systems and grind optimization.

Recoveries -- As summarized in Table 1 and associated graphs, recoveries of both Zn and Pb continue to display positive trends during the commissioning period (Table 1, Figures 1 & 2). The Company continues to remain focused on maintaining this positive trend over the coming months as it works to reach both Zn and Pb recovery design levels (as per the May 13, 2014 Preliminary Economic Assessment by SRK Consulting (Canada) Inc.) in a timely manner. Following this, Trevali will focus on both the copper circuit and precious metal by-products.


Figure 1: Graph of Zn concentrate grade versus circuit recovery from June through August. Red box indicates Caribou target grade -- recovery design window.


Figure 2: Graph of Pb concentrate grade versus circuit recovery from June through August. Red box indicates Caribou target grade -- recovery design window.

The mill is now producing consistent tails and operations will now focus on both increasing recoveries and mine head-grades toward design levels (as the mill continues to process the commissioning-phase coarse feed stockpile).

"We continue to deliver progress during Caribou commissioning and are pleased to see increasing volumes of concentrate sales. From September onwards, the commissioning team will principally focus on mill circuit stability, improving Zn and Pb recoveries, and continuing to increase mill throughput towards design levels, which is especially important in light of the current muted commodity price environment," stated Dr. Mark Cruise, Trevali's President & CEO. "Of all the base metals the macro-zinc outlook remains positive with overall strengthening demand for the metal generally anticipated as a result of supply constraints due to the very near-term closure of the Lisheen and Century mines in Ireland and Australia respectively by years-end. Ongoing exploration programs at our Santander Mine in Peru and advanced engineering studies at our Halfmile Mine and Stratmat project in New Brunswick should provide the Company with optionality to take advantage of any short-to-medium-term positive price movements."



Figure 3: Caribou Mine underground development and workings

Underground mining continued at a nominal 1,200 tpd rate during the month of August. Mining is currently maintaining an approximately 60,000-tonne coarse feed stockpile with approximate grades of 5.4% Zn, 2.2% Pb, 0.3% Cu, 60 g/t Ag and 0.8 g/t Au. With mill throughput increasing, mining will commence ramping-up production levels to the 3,000 tonne-per-day nameplate capacity over the forthcoming quarters.

Reconciliation to date shows good-to-excellent correlation between the block model, production sampling and mill-feed grades.

Underground dewatering is 92% complete -- there is presently 10.2 km of development in place and available for mining operations (Figure 3). In detail approximately 1.8 million tonnes are developed over 8 mining zones, of which approximately 1 million tonnes of mill feed is fully refurbished and currently available to mine. Production stope dilution year-to-date is 10.3% and development dilution is 16%, both well below design parameters for the (modified) Avoca mining method being utilized (originally modeled at approximately 22-26% dilution).

A 10,000-metre underground drill program commenced in the latter-half of August to both aid mining and convert inferred resources to a higher-confidence category. The program will be ongoing into H1-2016.


Metallurgical drilling has been completed at the Stratmat project and initial test work is scheduled to commence in September and will be ongoing during Q4-2015. At Halfmile the Company recently completed a geological confirmation drill program, the results of which will be utilized to revise the Halfmile geological model that will form the basis for future anticipated engineering studies.

Qualified Person and Quality Control/Quality Assurance

EurGeol Dr. Mark D. Cruise, Trevali's President and CEO and Mr. Paul Keller, P.Eng, Trevali's Chief Operating Officer, are qualified persons as defined by NI 43-101 and have supervised the preparation of 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. Mr. Keller is not independent of the Company as he is an officer and shareholder. On-site personnel at the project rigorously collect and track samples which are then security sealed and shipped to Bureau Veritas Minerals Laboratories (BVML) preparation facility in Val D'Or, Quebec for crushing and splitting and coarse rejects were assayed at BVML in Vancouver, BC. BVML quality system complies with the requirements for the International Standards ISO 9001:2000 and ISO 17025: 1999. Analytical accuracy and precision are monitored by the analysis of reagent blanks, reference material and replicate samples. Quality control is further assured by the use of international and in-house standards. Blind certified reference material is inserted at regular intervals into the sample sequence by Trevali personnel in order to independently assess analytical accuracy. Finally, representative blind duplicate samples are routinely forwarded to an ISO compliant third party laboratory for additional quality control.


Trevali is a zinc-focused, base metals mining company with one producing operation in Peru and another currently undergoing commissioning in Canada.

In Peru, the Company is actively producing zinc and lead-silver concentrates from its 2,000-tonne-per-day Santander mine.

In Canada, Trevali owns the Caribou mine and mill, Halfmile mine and Stratmat deposit all located in the Bathurst Mining Camp of northern New Brunswick. The Company is currently commissioning its 3,000-tonne-per-day Caribou mine.

All of the Company's deposits remain open for expansion.

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 ( and to Canadian regulatory filings on SEDAR at

On Behalf of the Board of Directors of
"Mark D. Cruise" (signed)
Mark D. Cruise, President

Contact Information:
Steve Stakiw
Vice President, Investor Relations and Corporate Communications

Phone: (604) 488-1661 / Direct: (604) 638-5623

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 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 resources, and not mineral reserves, and does not have demonstrated economic viability. Trevali's production plan at the Santander Mine is based only on 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.