A judge has quashed Alberta's decision to not allow environmental groups to take part in hearings on a proposed oilsands project.

The Oilsands Environmental Coalition went to court last month to challenge Alberta Environment's ruling involving an oilsands mine proposed by Southern Pacific Resource Corp.

The province said coalition members were not directly affected by the company's plan to build the project on the banks of the MacKay River in northeastern Alberta.

A government briefing note entered as evidence also suggested the coalition was being targeted for publishing negative media about the oilsands.

Justice Richard Marceau of Court of Queen's Bench called the government's actions "tainted" and "biased" in his written

judgment released Tuesday.

"It is difficult to envision a more direct apprehension of bias," he wrote.

"Accordingly the director's decision breaches all four principles of natural justice and must be quashed."

The coalition, which includes the Pembina Institute and the Fort McMurray Environmental Association, lauded the ruling.

"Albertans have a right to a fair oilsands regulatory process, including the right to be heard and raise concerns about oilsands development," said Simon Dyer, policy director for the Pembina Institute Wednesday.

Alberta Environment officials were not immediately available for comment.

The Pembina Institute said the Southern Pacific project would require up to 1.7 million litres of fresh groundwater each day and contribute to declining air quality.

The coalition is also concerned the mine would be located in the habitat of a threatened caribou herd.