The Donlin Creek mine is a proposed gold mine located in southwest Alaska. This prospect is expected to produce over a million ounces of gold per year, and has an estimated resource base of around 34 million ounces (over $40 billion at June 2010 prices), making it one of the largest undeveloped gold resources in the world. While not as large as the controversial Pebble Mine (100 million ounces of gold), the Donlin Creek mine prospect shares some of the same environmental concerns, including possible acid mine drainage, impacts on fish populations, and effects of cyanide use at the mine. Of the greatest concern at Donlin Creek is the possible release of thousands of pounds of toxic mercury, and the transportation off-site of many tons of mercury per year. However, due to the relatively remote location, the support of local native groups, and the lack of a significant commercial fishery in the watershed, the Donlin Creek mine has encountered virtually no opposition.
Donlin Creek bulk sampling site
source: Northern Alaska Environmental Center (2003). Copyright held by photographer.
The Donlin Creek mine prospect is in the Yukon-Kuskokwim Delta in southeast Alaska. The project is near Donlin Creek, 12 miles from the Kuskokwim River, and upstream of Crooked Creek. The nearest community is that of Crooked Creek, and Bethel is 120 miles downstream, near the mouth of the Kuskokwim River. Placer mining began in this area around the start of the 20th century, continued for over 50 years and then was followed by many years of exploration searching for the source of the placer gold. Exploration for this particular prospect has been underway since 1995.
Kuskokwim Corporation owns the surface rights to the land, and Calista Corporation owns the subsurface rights. The project proposal is being managed by a company called Donlin Creek LLC which is owned 50/50 by NovaGold Resources Inc. and Barrick Gold Corporation Inc.
The Donlin Creek project proposes an open pit mine, measuring up to 2 miles long and 1 mile wide. There is no infrastructure in the area, so the mine would need to construct an airstrip, housing, roads and a port on the Kuskokwim River in addition to the mine buildings themselves.
At Donlin Creek, solid rock waste would be stored in a pit near the mine and a valley nearby. Mine tailings would be stored in an artificial pond with a synthetic liner behind an earthen dam. The mine is expected to process 59,000 tons of ore per day for the 20-year lifetime of the mine, and to store over 2 billion tons of waste rock and tailings.
The mine would require an average 127 MW of power, with a peak load of 152 MW. The difficulty of providing this power has been a significant hurdle during the planning process. Discarded options have ranged from constructing a coal-fired power plant near Bethel, to on-site nuclear. In the 2009 feasibility study for the mine (8.9 megs), the operators settled on river-transported diesel and a small wind farm. Under this scenario, large amounts of diesel would be barged upriver from Bethel every day to a newly constructed port site, and then transported to the mine via a 74 mile-long buried pipeline. However, as of May 2010, the mine is considering building a natural gas pipeline from Cook Inlet that would replace both the diesel and the wind farm.
Three of the major environmental concerns relating to the proposed Donlin Creek mine are potential acid mine drainage, mercury contamination, and the effects of cyanide usage at the mine.
Much of the rock at the Donlin Creek site contains iron sulfides that, when exposed, react to generate sulfuric acid. The feasibility study for the mine implies that active water treatment will need to continue forever after the closure of the mine to mitigate this acid.
Another concern is the large amount of toxic mercury naturally contained in the rock in the area. The mine plan calls for capturing the mercury in at least six different stages in the mining process, but concerns remain about residual release. The EPA is currently reviewing new regulations for mercury emissions at gold mines, but some groups have argued that even under the new, more stringent rules, Donlin Creek could still emit up to 3,200 pounds of mercury into the air per year. Additionally, the mine will be capturing tens of tons of mercury per year that will need to be safely transported off-site for sale or disposal.
Also of concern is the impact of dramatically increased barge traffic on the Kuskokwim River. Villages along the river worry about increased noise and wave levels, as well as the risk of a diesel spill on the river like the one that occurred near the Iliamna River in 2009.
Donling Creek exploration roads
source: Northern Alaska Environmental Center (2003). Copyright held by photographer.
The Donlin Creek mine has the support of most of the villages within the Yukon-Kuskokwim Delta mainly due to the prospects for employment. Construction of the $4.5 billion mine would take around 3 years, and employ 1500-2000 people. The mine expects to operate for 20 years, while directly employing 600-800 people. Donlin Creek LLC expects some jobs to last even longer, relating to closure, reclamation, and site monitoring. To date, 90% of the people involved in the exploration process have been residents of the region, and Calista shareholders have a contractual hiring preference.
While metals mining returns far fewer tax dollars directly to the state than fossil fuel extraction (see Pebble Mine article "Employment and Economics"), the Donlin Creek mine would still have a very large impact on local and regional communities in terms of revenue and reduced welfare payments. Some profits from the mine would be distributed to other native corporations throughout the state via the Section 7(i) clause in the Alaska Native Claims Settlement Act. In addition to increased revenues, the mine has indicated that they will most likely produce extra electrical power that could be sold to the surrounding communities at a lower price than what is produced by the existing diesel generators in the area.
NovaGold and Barrick budgeted $47 million for work on the Donlin Creek prospect during 2010, primarily including funding for work on revising the mine plan to include a natural gas pipeline or to import LNG instead of using transported diesel. The work is expected to take 12-18 months, and the company hopes to begin filing permit applications by the end of 2011.
By David Coil, Elizabeth Lester, Bretwood Higman, Ground Truth Trekking
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