Job Openings About Our Plan Sustainability Community Careers Safety Contact Jobs and Education Opportunities Project Summary Community EVENTS JAN 01 NEW YEAR’S DAY January 1, 2022 JAN 07 SLAVIQ NATIVITY OF CHRIST (RUSSIAN ORTHODOX) January 7, 2022 JAN 21 MARTIN LUTHER KING JR. DAY January 21, 2022 FEB 02 GROUNDHOG DAY February 2, 2022 FEB 14 VALENTINE’S DAY February 14, 2022 FEB 16 ELIZABETH PERATROVICH DAY February 16, 2022 FEB 18 PRESIDENT’S DAY February 18, 2022 JAN 01 NEW YEAR’S DAY January 1, 2023 JAN 07 SLAVIQ NATIVITY OF CHRIST (RUSSIAN ORTHODOX) January 7, 2023 JAN 21 MARTIN LUTHER KING JR. DAY January 21, 2023 View More… SIGN UP FOR OUR NEWSLETTER Name * Email * By providing your e-mail address, you are consenting to receive press releases and other information concerning Donlin Gold LLC and its affiliates and partners. You may withdraw your consent at any time. Every person going home safe and healthy every day. Get in touch. Donlin Gold LLC 2525 C St., Suite 450 Anchorage, AK 99503 T: (888) 225-7590 or (907) 273-0200 © 2021 Donlin Gold LLC. All rights reserved

Job Openings About Our Plan Sustainability Community Careers Safety Contact Environment TAILINGS MANAGEMENT PLAN After extracting the gold, wet tailings resembling silt will be a byproduct of the milling process. A containment dam, engineered to withstand environmental events and changes typical of Alaska, will be built to house the tailings. Downstream-constructed dams are considered the most stable design for tailings dams and are the most suitable for retaining large volumes of water. Information about the State of Alaska’s Dam Safety Program can be found here. The tailings storage facility (TSF) contained within the dam will have a 60-mil. (.06-inch), textured, linear, low-density, polyethylene liner. The ultimate size of the facility will be approximately 1.75 miles long by 1 mile wide. This preventative measure is not required under state mining regulations and demonstrates the high level of environmental stewardship Donlin Gold brings to the project. A 60-mil., textured, linear, low-density, polyethylene liner will be anchored to the bedrock of the TSF. When the mine is no longer in operation, the tailings-storage facility will be covered with rock, gravel and soil, planted with vegetation, and re-contoured to blend in with the surrounding terrain. The TSF 50 years after mine closure. A full overview of the TSF can be downloaded here. Every person going home safe and healthy every day. Sign up for our newsletter. Name * Email * By providing your e-mail address, you are consenting to receive press releases and other information concerning Donlin Gold LLC and its affiliates and partners. You may withdraw your consent at any time. Get in touch. Donlin Gold LLC 2525 C St., Suite 450 Anchorage, AK 99503 T: (888) 225-7590 or (907) 273-0200 © 2021 Donlin Gold LLC. All rights reserved