The commission rejected the controversial proposal by a vote of 8-4 on Thursday, following five years of legal wrangling.
'In 38 years of this commission's existence, this is one of the three worst projects that I've seen in terms of environmental devastation,' said Peter Douglas, the agency's executive director.
'It's a contradiction in terms - you can't be serious about being an environmentalist and pick this location' given the effects on habitat, land formation, scenic views and water quality.
According to the report, lawyers for The Edge are now expected to challenge the decision in court.