Dr. Mark Cruise reports

TREVALI COMMENCES MINING AT CARIBOU ZINC MINE IN ANTICIPATION OF Q2 MILL COMMISSIONING

Trevali Mining Corp. has provided a status update on construction and mine restart activities at its wholly owned Caribou polymetallic mine and mill complex located in the Bathurst mining camp of northeastern New Brunswick, Canada.

Both surface and underground development programs at Caribou have advanced significantly during the first quarter, including the recent commencement of mining activities. The project status remains on schedule for start-up commissioning in the second quarter of 2015. A summary of key current activities is provided as follows.

Mill

• The milling circuit is predominantly refurbished and ready for operation with the new 3,000-tonne-per-day semi-autogenous-grinding (SAG) mill installed and aligned. The two ball mills have been refurbished and will be available for commissioning following coming replacement of upgraded trunnion seals. The three M1000 IsaMills have been inspected and are in excellent condition. The company has pro-actively replaced motor bearings, following which they will be available for commissioning.
• The zinc and lead flotation circuits and associated pumps have been refurbished or replaced and are ready for commissioning. The copper circuit design has been completed, tendered, with the majority of equipment sourced (from the former Brunswick-12 mill) and on site. During the commissioning period, the company intends to initially focus on the established zinc and lead (silver) recovery circuits, following which it will commission the new copper circuit.
• In order to potentially fast-track mill commissioning and technically derisk start-up, Trevali's mill operations team recently travelled to Australia to visit partner Glencore's Mount Isa and McArthur River zinc operations for knowledge transfer opportunities in IsaMill operations, fine-grind flotation performance, maintenance practices and troubleshooting. Additionally, experienced Glencore IsaMill operational specialists will be made available to assist Trevali's technical team on site at Caribou during the coming mill commissioning and ramp-up. Trevali's team also took the opportunity to examine and discuss various other potential postcommissioning opportunities with its Glencore counterparts.
• DRA Americas Inc., a South African specialist metallurgy and plant operations group, has also been retained to provide additional expert support to the Caribou team as Trevali commences mill commissioning and metallurgical optimization going forward. The DRA team has mobilized to site and is currently working on enhancing the mill maintenance programs in order to maximize equipment availability both during and after commissioning periods.

Underground

• Initial underground mineral production has commenced with blasting of the first scheduled stope and transport of mineralized mill feed to the surface stockpile. There is currently an estimated 18,000 tonnes on the coarse-mill-feed pad with this amount increasing on a daily basis. Based on experienced gained during the very successful Santander plant commissioning in Peru, the company plans to build a significant stockpile of mineralized material (approximately 60,000 to 80,000 tonnes) over the interim period prior to commencing mill commissioning in the second quarter.
• Approximately three years of underground development is currently in place. In detail, ramp, level rehabilitation and access to the first four production zones are now 100 per cent complete, and rehabilitation of the fifth zone is approximately 80 per cent complete. There is currently approximately one million tonnes of mineralized material available for production.
• The construction of an underground ramp connection to the existing conveyor portal (approximately 400 metres of development) has been completed and is anticipated to result in significant operational efficiencies by reducing the underground haul distance to within approximately 100 metres of the fine-mill-feed bins versus the previous approximately 1.5-kilometre surface haul route. It is anticipated that this will decrease haul costs (shorter haul using larger trucks), improve underground fleet availability in addition to improving winter production capabilities.
• The mine is now approximately 80 per cent dewatered, based on volume, with approximately 100 vertical metres remaining. Upgrading of the water treatment plant and settling ponds is under way to roughly double capacity of water treatment plant from 600 gallons per minute to plus 1,200 gallons per minute in order to provide greater flexibility in water management going forward.

Surface works

All critical surface works required for initial commissioning have been completed. Additional work will occur after seasonal spring melt.

Staffing

Caribou staff and contractor numbers have ramped up in accordance with mine and mill activity levels as operations approach commissioning. Total site personnel (comprising Trevali Caribou employees, staff and contractors) currently stand at approximately 230.

Total anticipated site personnel (both employees/staff and contractors) once operations are fully ramped is expected to be approximately 300.

First nation training programs

As part of Trevali's continuing impact benefit agreement with local Mi'kmaq First Nations, mining and mill training programs have been initiated to provide qualified first nation candidates with the skill sets to take advantage of Trevali's goal of 20 per cent first nation work force participation at Caribou. There are presently 11 first nation students in the underground mining common core program who are presently on the practical portion of training at the Caribou mine. As well, there are 12 first nation candidates who are on their sixth week of a 12-week mill operator training program. Both programs are being run through the local community colleges.

Upon the completion and employment of these first nation candidates, Trevali is proud to announce that it will be one of the largest first nation employers in New Brunswick.

Zinc commodity outlook

Zinc market fundamentals continue look very strong as London Metals Exchange inventory levels see continued drawdowns and are now at plus-five-year lows, approaching the 515,000-tonne level. Coupled with this are the scheduled closures of both MMG Ltd.'s Century mine in Australia and Vedanta Resources PLC's Lisheen mine in Ireland later this year, which have estimated 2015 annual productions of approximately 320,000 to 370,000 tonnes and 160,000 tonnes of zinc in concentrate, respectively.

According to the International Lead and Zinc Study Group, zinc production lagged consumption by 296,000 tonnes in 2014 as stockpiles were being consumed. This production deficit is forecast to almost double to approximately 580,000 tonnes this year and could widen to as much as two million tonnes in 2017 with no new, global marquee zinc mines scheduled to commence production within this period.

Trevali is the only primary zinc producer (as defined by greater than 50 per cent revenues derived from zinc production and sales) currently listed on the Toronto Stock Exchange.

Qualified person and quality control/quality assurance

Dr. Mark D. Cruise, EurGeol, Trevali's president and chief executive officer, and Paul Keller, PEng, Trevali's chief operating officer, are qualified persons as defined by National Instrument 43-101, 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.

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