Eastmain Announces Fall 2018 Pre-Development and Exploration Activities at the Eau Claire Project and Clearwater Property

TORONTO, Sept. 10, 2018 - Eastmain Resources Inc. (“Eastmain” or the “Company”- TSX:ER, OTCQX:EANRF) is pleased to announce its Fall 2018 activities at its 100%-owned Eau Claire Project and surrounding Clearwater Property.

Fall 2018 Program

Eau Claire Project

• Post-PEA pre-development activities include:
  • Engineering studies for the underground exploration ramp project
  • Environmental and infrastructure studies
• Exploration activities including a drilling program of up to 2,000 m at Eau Claire to test the eastern plunge of the deposit at depth and to confirm mineral continuity in certain areas of the deposit

Clearwater Property Exploration

• Exploration activities include:
  • Mapping, soil and outcrop sampling program
  • 1,600 m trenching program to investigate the Cannard Deformation Zone
  • 5,500 m drilling program to test targets along the Cannard Deformation Zone

These exploration activities are in support of Eastmain’s 3-in-3 Exploration Vision which aims to define 3 million ounces of total mineral resources in 3 years.

Claude Lemasson, President & CEO, stated: “After issuing a robust PEA for the Eau Claire Project in May 2018, we are pleased to actively advance the project through key pre-development activities while continuing promising exploration nearby on the rest of the Clearwater Property. To review the progress on this work, several members of Eastmain’s board of directors and senior executives visited the site last week.”

Eau Claire Project

Eastmain continues to move forward with its pre-development plans for the Eau Claire Project. In May 2018, the Company announced a positive Preliminary Economic Assessment (PEA) at Eau Claire with an after-tax NPV_5% of $260 million and an after-tax IRR of 27%. The PEA incorporates mineral resources of 4,294,000 tonnes grading 6.18 g/t Au (853,000 oz) in the Measured & Indicated categories and 2,382,000 tonnes grading 6.53 g/t Au (500,000 oz) in the Inferred category. The PEA proposes a 12-year mine life with production from two small open pits followed by underground operations. A detailed description of the PEA is available in a press release dated May 23, 2018 and from the PEA Technical Report.

Based on the PEA recommendations, Eastmain is moving forward with studies related to advanced exploration of the Eau Claire deposit through underground exploration and bulk sampling. For the remainder of the year, the Company will work to complete a conceptual design, cost estimates and a schedule for an advanced exploration project consisting of a ramp to reach the main mineralized zone of the deposit at depths of approximately 200‐300 m from surface. The objectives of the ramp are to collect a 25,000-tonne bulk sample representative of deposit mineralization suitable for metallurgical and process testing and to generate geo-technical information suitable for use in feasibility level studies regarding stope design, rock mechanics, mining dilution and ore continuity. In addition to engineering studies, environmental and infrastructure studies are also being defined to begin during the balance of 2018.

At Eau Claire, drilling will test targets developed from review of the Eau Claire PEA completed in May 2018, particularly the eastern plunge of the deposit located between 400 m and 700 m (see Figure 1).

Clearwater Property

At the Clearwater Property, which hosts the Eau Claire Project, a surface exploration program began in July with a focus on property-wide (20,068 ha) helicopter supported mapping, soil and outcrop sampling. Numerous historic showings were revisited and new regional geological interpretations prepared earlier in the year were ground tested. Since beginning the field work 976 samples were taken from 795 outcrops across the property. Thirty-two glacial boulders were sampled and 1,004 soil samples were taken in the Knight and Serendipity areas in the eastern sector of the claim group. Eastmain geological staff are currently reviewing analytical results of this program (see Figure 2).

In September, Eastmain staff will focus on completing a 1,600 m trenching program to investigate the Cannard Deformation Zone which extends from east to west along the southern boundary of the property and includes the Snake Lake, Clovis and Natel showings as well as gold mineralized occurrences in the Casey granite complex.

A diamond drilling campaign of up to 5,500 m is planned for Clearwater for the fall period. The campaign will test targets along 16 km of the Cannard Deformation Zone including Snake Lake, Clovis, Knight, Natel and Serendipity. The Beluga prospect, located 4 km north of the Eau Claire Deposit will also be tested.

To view FIGURES 1 and 2 please click on the following link: http://www.eastmain.com/_resources/images/Figures_1-2.pdf

About Eastmain Resources Inc. (TSX:ER, OTCQX:EANRF)

Eastmain is a Canadian exploration company advancing three high-grade gold assets in the emerging James Bay gold camp in Québec. The Company holds a 100% interest in the Eau Claire Project, for which it recently issued a Preliminary Economic Assessment (“PEA”), and the Eastmain Mine Project where the Company prepared a NI 43-101 Mineral Resource Estimate in 2018. Eastmain is also the manager of the Éléonore South Joint Venture which hosts a new high-grade gold discovery found in late 2017 and is located immediately south of Goldcorp Inc.'s Éléonore Mine. In addition, the Company has a pipeline of exploration projects in this favourable mining jurisdiction with nearby infrastructure.

Forward-Looking Statements - Certain information set forth in this news release may contain forward-looking statements that involve substantial known and unknown risks and uncertainties. Forward-looking statements consist of statements that are not purely historical, including statements regarding beliefs, plans, expectations or timing of future plans, and include, but not limited to, statements with respect to the potential success of the Company’s future exploration and development strategies. These forward-looking statements are subject to numerous risks and uncertainties, certain of which are beyond the control of Eastmain, including, but not limited to the impact of general economic conditions, industry conditions, dependence upon regulatory approvals and the availability of financing, timely completion of proposed studies and technical reports, and risks associated with the exploration, development and mining industry generally such as economic factors as they effect exploration, future commodity prices, changes in interest rates, safety and security, political, social or economic developments, environmental risks, insurance risks, capital expenditures, operating or technical difficulties in connection with development activities, personnel relations, the speculative nature of gold exploration and development, including the risks of diminishing quantities of grades of Mineral Resources, contests over property title, and changes in project parameters as plans continue to be refined. Readers are cautioned that the assumptions, used in the preparations of such information, although considered reasonable at the time of preparation, may prove to be imprecise and, as such, undue reliance should not be placed on forward-looking statements. The Company assumes no obligation to update such information, except as may be required by law.