Kensington Open Pit Mine
The Kensington Gold mine is located 45 miles northwest of Juneau, Alaska in the Tongass National Forest near Berner’s Bay. It is composed of two prospects (Jualin and Kensington). It is owned by the company Coeur Alaska Inc., a Chicago-based company. Production in 2018 was 113,778 oz Au.
The mining process involves an underground mine, an ore storage facility, and a waste rock storage facility. Mining was halted in 2009, but resumed again in late 2010 and is fully operational to this day.
Environmental concerns plagued the property, as several conservation groups protested the proposed depositing of the tailings directly into the Lower Slate Lake. The arguement was that it would kill the aquatic ecosystem. Today they have a method for depositing the tailings underwater in the lake using a dam system. This issue became so important to the mining world that it made its way to the Supreme Court.
The U.S. Supreme Court ruling allowed the dumping of the tailings into the lake. It is feared to affect future mining rulings and other mining proposals on aquatic and wildland habitats. Time will tell the full effect of these dumpings to the environment.
In the meantime, Coeur is trying to reduce their carbon footprint. You can read about their efforts on their website https://www.coeur.com/responsibility/environment/