Tom Collier, CEO of Alaska's Pebble mining project, stepped down after tapes highlighting his connections to Alaska politicians and regulators were leaked.
The taped comments hint at Collier's relationship with Alaska Governor Mike Dunleavy, Senators Lisa Murkowski and Dan Sullivan.
Northern Dynasty, the company seeking to begin mining in Alaska's salmon-rich Bristol Bay region, apologized to all Alaskans for Collier's "offensive" comments. The conversation between Collier and others was videotaped by two unknown people posing as representatives of a Hong Kong-based investment firm.
The Environmental Investigation Agency released the tapes Monday after covering the voices and identities of the two people acting as investors.
Former Pebble CEO John Shively will act as interim CEO until the company finds a suitable candidate for the role.
In July, the US Army Corps of Engineers released its Final Environment Impact Statement (EIS) for the controversial Pebble Mine, angering fishermen who have been protesting the project for more than a decade.