Seattle Post-Intelligencer: The city of Seattle has temporarily stopped buying biodiesel fuel for its fleet of vehicles because of concerns that the soy-based mix it was using was more harmful to the environment than regular diesel. But Brenda Bauer, director of Seattle’s Fleets and Facilities Department, said the city could start using a different type of biodiesel made from waste grease — byproducts of food production. “Not all biodiesels are the same,” Bauer said. She said Mayor Greg Nickels …