Source: Trevali Mining Corporation

Trevali Identifies Laterally and Vertically Extensive High-Grade Silver-Gold Mineralization at Past Producing Huampar Silver Mine in Peru

Historical mine level channel sample of 334.2 metres grading 4.53 oz/T silver, 5.46 g/t gold, 4.04% zinc, 4.34% lead and 0.32% copper

VANCOUVER, BRITISH COLUMBIA--(Marketwire - Aug. 10, 2011) - Trevali Mining Corporation ("Trevali" or the "Company") (TSX:TV)(OTCQX:TREVF)(BVLAC:TV)(FRANKFURT:4TI) is pleased to announce results from a recent structural interpretation and 3-D compilation of historic underground data at the past producing Huampar Silver-Gold (polymetallic) mine in Peru. The interpretation confirms that the Finlandia Veins system at Huampar contains long lateral and vertical intervals of high-grade precious and base metal mineralization.

Level 428-8: 317.1 metres of 3.84 oz/T Ag, 4.46 g/t Au, 3.7% Zn, 2.85% Pb, 0.39% Cu

Level 421-13: 220.36 metres of 11.94 oz/T Ag, 9.70% Zn, 10.51% Pb, 0.92% Cu

Level 421-21: 334.2 metres of 4.53 oz/T Ag, 5.46 g/t Au, 4.04% Zn, 4.34% Pb, 0.32% Cu

All of the mine levels are characterized by excellent horizontal and vertical continuous 'mineralized-shoots' that are traceable over the four deepest production levels and extend to depth of approximately 170 vertical metres where they remain open for expansion (Fig. 2, Tables 1 and 3).

"The intensity of precious and base metal mineralization coupled with the impressive vertical and lateral continuity of the Finlandia System is highly encouraging and suggests that there is excellent exploration potential along-strike and down-dip of the historic workings," stated Dr. Mark Cruise, Trevali's President and CEO. "We are currently prioritizing drill targets as part of a forthcoming resource confirmation and expansion program with drilling to commence as soon as possible."

The Huampar mine contains a historic, non-compliant National Instrument ("NI") 43-101, mineral reserve* of 874,412 tonnes grading 1.3 g/ gold, 209 g/t silver, 3.31% lead and 3.63% zinc in addition to minor copper mineralization. Site infrastructure includes a 600-person camp and a fully permitted 400 tonne per day (tpd) mineral processing plant. The large, 1,450 hectare land package has seen limited historic exploration - the Company believes that there is excellent potential to discover additional mineralization with the ultimate aim of recommencing mining operations (please see TV NR-11-14 for additional details).

Table 1. Selected along-strike composite assay values
Composite Length Ag Au Zn Pb Cu Avg. Width
Sample (m) (oz/T) (g/t) (%) (%) (%) (m)
LEVEL 412
412-1 254.76 3.33 N/A 1.83 2.10 0.29 1.35
412-3 83.85 4.88 N/A 2.77 1.77 0.17 0.61
412-14 273.88 2.78 0.84 3.39 2.38 0.38 1.24
412-15 112.47 3.63 2.67 2.94 3.31 0.17 0.83
412-19 229.65 6.09 N/A 4.36 7.04 0.37 0.72
LEVEL 416
416-5 279.46 3.61 0.63 2.82 2.67 0.22 1.04
416-10 178.20 2.25 6.49 1.94 1.21 0.26 1.13
LEVEL 421
421-13 220.36 11.94 N/A 9.70 10.51 0.92 0.77
421-20 233.79 1.83 0.74 1.91 1.78 0.24 0.90
421-21 344.20 4.53 5.46 4.04 4.34 0.32 0.71
LEVEL 428
428-1 293.40 1.07 N/A 2.66 1.45 0.08 0.78
428-5 175.06 4.33 0.43 2.58 2.11 0.14 1.18
428-8 317.10 3.84 4.46 3.70 2.85 0.39 1.36
428-10 197.88 2.89 1.23 4.57 2.60 0.26 0.62
N/A - Not applicable due to insufficient gold analyses.

*The Company cautions that the reserve estimates were prepared before the introduction of NI 43-101 reporting requirements, and are therefore only historical in nature. The Company is not treating such estimates as a current reserve or resource under NI 43-101. Investors are further cautioned that a qualified person has not yet completed sufficient work to be able to verify the historical reserve estimates, and therefore they should not be relied upon.

COMPILATION DATABASE

Historical silver, gold, zinc, lead and copper assay data was obtained from the Huampar Mine Lab for 2,116 subsurface rock channel samples (collected between 1984 and 1991) from the four deepest mine levels (428, 421, 416 and 412). Channel samples oriented perpendicular to the Finlandia Vein (average sample width is 0.96 metres) at 2 or 3 metre intervals cover 3,325 metres along-strike and 170 vertical metres of the Finlandia Vein System (Fig. 2). Composite assay values are calculated along the strike of the vein in order to determine the distribution of grade and continuity of silver, gold, zinc, lead and copper (Fig. 2, Table 1).

Samples that returned trace values, samples that were not analyzed or were omitted from mine plans have been assigned a value of zero. Thus, based on the data the composite grade calculations most likely underestimate the grade of the Finlandia System. The range of silver, gold, zinc, lead and copper, along with their average values are reported in Table 2.

Gold assays were not routinely conducted at Huampar until 1991. The distribution of silver, gold, zinc, and lead is shown on a composite level plan that includes levels 428, 422, 416 and 412 (Fig. 2). Each of these metals has a similar distribution (i.e., a strong positive correlation) and mineralized zones are traceable over hundreds of metres along strike and across multiple mine levels (Fig. 2).

Table 2. Statistics for Samples (N=2116)
Element Range Average
Silver 0 - 79.6 oz/T 3.1
Gold* 0 - 158.0 g/t 1.2
Zinc 0 - 71.0 % 3.1
Lead 0 - 28.8 % 2.48
Copper 0 - 6.37 % 0.22

GEOLOGY

The property is located in the south-central portion of the Central Peruvian Polymetallic Belt. The claims are underlain by moderately folded, 200 metre- to 1 kilometre-thick package of andesitic volcanic rocks beneath which occurs an approximately 1 kilometre-thick sequence carbonates and clastic sedimentary rocks: the Jumasha, Chulec and Santa Formation limestones, proven host sequences throughout Peru, including the Company's Santander project as well as many mines within the greater Huampar district (Felicidad and Poderosa mines).

The property is transected by several large scale (+5-km long) ENE trending fracture zones (Fig. 2). Structurally controlled mineralization is primarily hosted within sub-vertical, ENE trending vein-fault systems. Mineralized veins typically have significant strike lengths (+1-km) and considerable depth potential (~+800m) (Fig. 1).

Previous exploration was limited to drifting on exposed veins and underground cross-cuts designed to test for and intersect (successfully) sub-parallel structures. No exploration in the modern sense has occurred on the property (geophysics, geochemistry, drilling).

MINERALIZATION

The principal Finlandia vein system consists of at least five major veins of variable widths ranging from 0.2 to 2.5 metres and averaging approximately 1 metre wide for an aggregate distance of approximately 5 kilometres strike length (Fig. 1). The Aurelio vein system, approximately 2 km north of Finlandia, is a gold and silver rich vein system with an average width of 1 metre and a length of approximately 400 metres. The Condor Paso vein system is located approximately 6 km south of the Finlandia and is continuous for 2 km along strike (Fig. 1). All vein systems remain open for expansion.

In past mining operations, mineralization was exploited using a combination of cut and fill and shrinkage mining methods from surface to vertical depths ranging from 50 to 450 metres below surface. Similar polymetallic mines in the district contain economic mineralization over vertical intervals of 500 to 1000 metres suggesting good to excellent additional resource expansion potential at depth.

BRIDGE LOAN FACILITY

Trevali has repaid in full the previously announced US$10 million Bridge Loan Facility with Resource Income Fund, L.P. of Fort Lee, New Jersey. The Company has also signed a term sheet with Resource Income Fund, L.P. for a Stand-by Loan Facility of up to US$7.5 million for mine development and working capital purposes towards its Halfmile and Stratmat projects in New Brunswick. The facility is subject to among other things, customary due diligence by Resource Income Fund, and ultimately the acceptance of the final terms by Trevali's Board of Directors.

ABOUT TREVALI MINING CORPORATION

Trevali is advancing two polymetallic (zinc-lead-silver-copper) deposits to production in Canada and Peru – the Halfmile and Santander projects respectively. In Canada, Trevali has the Halfmile and Stratmat polymetallic deposits near Bathurst, New Brunswick, and the Ruttan copper-zinc deposit in northern Manitoba. Mine development is underway at Halfmile with a proposed production rate of 2,000-tonnes-per-day anticipated to commence in late 2011. In Peru, the Company has the Santander zinc-lead-silver mine project and the formerly-producing Huampar silver mine, both located in the Central Peruvian Polymetallic Belt.

At Santander, in conjunction with Glencore International A.G., mine commissioning is anticipated to commence at 2,000-tonne-per-day in late 2011 with full production to follow immediately thereafter. Additionally through its subsidiary Trevali Renewable Energy Inc., Trevali is undertaking a significant upgrade of its wholly-owned Tingo run-of-river hydroelectric generating facility along with transmission line upgrades and extensions to allow, in addition to supplying power to the mining operation on the property, the potential sale of surplus power into the Peruvian National Energy Grid.

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

Qualified Person and Quality Control/Quality Assurance

EurGeol Dr. Mark D. Cruise, Trevali's President and CEO and a qualified person as defined by National Instrument 43-101, has 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 and shareholder.

The data compilation and interpretation at Huampar work was designed by, and is supervised by, Mark D. Cruise, President & CEO of Trevali and Dan MacNeil (Senior Geologist) who together are responsible for all aspects of the work, including the quality control/quality assurance programs.

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 accuracy of estimated mineral reserves and resources, anticipated results of future exploration, and forecast future metal prices, anticipated results of future electrical sales and expectations that environmental, permitting, legal, title, taxation, socio-economic, political, marketing or other issues will not materially affect estimates of mineral reserves. 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 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 reserves 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.

To view the Figures associated with this release, please visit the following link: http://media3.marketwire.com/docs/tv810Figs.pdf

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

Contact Information:

Trevali Mining Corporation
Steve Stakiw
Manager - Corporate Communications
(604) 488-1661
(604) 408-7499 (FAX)
sstakiw@trevali.com
www.trevali.com