Two hundred square miles of land on the Blackfeet Indian Reservation just east of Glacier National Park in Montana could soon become a huge industrial oil and natural gas development, covered with wells, roads, power lines, and processing stations. Despite the protest of the EPA and some enviros, the Interior Department’s Bureau of Indian Affairs has approved a 50-year lease agreement between the Blackfeet Tribe and a Canadian oil company to develop the now mostly open land — home for part of the year to the park’s bear, elk, wolves, and eagles — without preparing an environmental impact statement. Tribal leaders, who are trying to cope with a nearly 70% unemployment rate and make do with a land base that has repeatedly been diminished over the years, say they resent outsiders telling them how to manage their lands.