Athabasca Oil is working with PetroChina under the Dover Operating Co. to develop oil sands about 60 miles north of Fort McKay in northeastern Alberta.
Athabasca in 2009 signed a development deal with PetroChina worth at least $1.9 billion. The project could reach a daily production capacity of 250,000 barrels of oil per day.
Dayle Hyde, a spokesman for Fort McKay First Nations, was quoted by the Platts news service as saying the Dover group hadn't take action to protect regional lakes and wilderness areas.
"Over the years, we have supported sustainable oil sands and economic development for our community," he said. "But the Dover project will seriously impact the last remaining traditional reserve land on the west side of the Athabasca River."
Canadian oil sand reserves are among the largest in the world. The type of crude oil found in Alberta oil fields is considered more of an environmental threat than conventional crude oil.
Local groups in eastern British Columbia have objected to plans to get Alberta crude oil to Asian markets. The Canadian government aims to expand its export options in a market that relies almost exclusively on the United States.