Unlike conventional crude , unstabilized dilbit floats briefly in water but heavier components sink as light components evaporate . The remaining bitumen can make cleaning up a dilbit spill more difficult than a conventional oil spill , particularly if dredging is considered too ecologically damaging . During the 2010 Kalamazoo River oil spill , the heavier components combined with silt and sank to the bottom of the water column , making cleanup difficult . Cleanup of the spill was still underway three years after the event , and officials at the Michigan Department of Natural Resources ' Fishery Division stated that it will " be many more years before the agency can measure the full impact on fish and other animals ' reproductive cycles . " However , studies show that dilbit does not increase the risk of corrosion occurring within a pipeline or otherwise increase the risk of a release occurring
Kalamazoo River oil spill
Kalamazoo River oil spill
Dilbit