While the spill was relatively small compared ... Line 6B sent more than 843,000 gallons of tar-sands crude oil into the Kalamazoo River watershed near Marshall, Michigan, in 2010.

Two leaking oil wells from the 1940s have been plugged to prevent further oil spills into an Ottawa County lake.

After crews were able to contain the leak, now environmental groups are working to learn if there was any damage done.