Page 26 - NG_AR_2017

f Mercury Questions have been raised about mercury emissions and associated risks from the Donlin Gold project,
in part because mercury levels are already elevated in the Y-K region due to existing natural and man-made sources. As part of our extensive environmental studies, Donlin Gold conducted a detailed evaluation of existing mercury levels and risks, as well as the potential impacts of project emissions. In fact, our emissions will be minimized by state-of-the-art controls. These scienti c studies provide valuable information to the agencies and public in understanding and, as needed, addressing existing and potential future mercury concerns.
In addition, we have more than 10 years’ worth of water
quality monitoring at Donlin Gold, establishing baseline data to evaluate potential environmental impacts and provide defensible documentation in support of permitting. This data has supported
the project design, including processing and water management
and treatment system design, as well as closure planning. Our water management plan takes into account the full range of climatic conditions during the life of mine and closure, maximizing water reuse to the extent practicable while providing for discharge exibility for excess water, and balancing environmental concerns with operational needs. All discharges must meet Alaska water quality standards at
the point of discharge; all data and analyses were developed with input from both federal and state agencies to ensure compliance with anticipated permit requirements.
Our approach to waste rock management is a clearly de ned method developed to identify and separate Non-Acid Generating (NAG) and Potentially Acid Generating (PAG) rock. We’ll segregate and isolate low volumes of PAG rock and manage NAG rock to address predicted metal leaching, with all seepage and runo to be collected and treated as needed.
Our design for closure at Donlin Gold is built on the following objectives: minimize the project’s footprint, maximize concurrent reclamation, and provide for the long-term stability of the site under a range of future climatic conditions. This includes the innovative plan for dry closure of the tailings storage facility. In addition to minimizing the accumulation of water, we see the pit lake as key to closure water management, with the seasonal treatment of its water after lling, up to 60 years post-closure. To ensure long-term care and maintenance of the project post-closure, Donlin Gold proposes to establish and pay into a trust fund during operations to provide su cient resources for such activities.
Operating and powering the mine will require that fuel and
other supplies be transported to the site. Many of these materials will be transported to the project by barges traveling up and down the Kuskokwim River during the shipping season (June–October). While the potential for a spill is extremely unlikely because of the safeguards that have been included in the transportation plan, the Donlin
Gold project will have an emergency Spill Response Plan ready to implement if a spill does occur. That plan will include staged response equipment at di erent locations along the transportation corridor and trained response crews.
24