Green Bay Press Gazette: Oil that sinks is hard to clean up. That was the big lesson after energy giant Enbridges pipeline burst, causing oil to flow into Michigans Kalamazoo River in 2010, some 75 miles from where it empties into Lake Michigan. After more than three years and a billion dollars, oil remains in the river. So a refinerys proposal to ship heavy crude oil from Superior across the Great Lakes has emergency responders gearing up to bolster gaps in current oil spill response plans. And the gaps are substantial,...