One of their favourite lies is to claim that the product they'll be shipping, diluted bitumen or dilbit, actually floats. They want the public misled into believing the stuff floats and, therefore, can be recovered by oil spill scavenger vessels, booms, etc.
Some diluted bitumen products will sink in fresh and brackish marine waters in less than 26 hours following a tanker spill or accident at a marine terminal.
That's the conclusion of new report by Jeff Short, a highly respected U.S. environmental chemist who worked with for National Oceanographic and Atmospheric Administration (NOAA) for decades.
Short directed much of the groundbreaking research on the impact of the Exxon Valdez spill on aquatic life. His research found that oil's toxic properties lasted as long as two decades in marine waters.
One Enbridge expert, Alan Maki, even claimed that bitumen was buoyant: "It is an immutable fact of physics that they will float. They simply cannot sink in water."
Other testimony including a report by SLRoss Environmental Research, a Calgary engineering firm, claimed that bitumen would most likely stay on top of the ocean too.
"I had some real reservations about the conclusions of SLRoss report which wrote off the possibility of bitumen sinking," explained 63-year Short to The Tyee.
The SLRoss study based its findings on a limited laboratory experiment that Enbridge filed as evidence at the last minute with the NEB.
Short explained that if the SLRoss study had repeated their limited laboratory experiment at slightly lower water (and more realistic) temperatures at higher wind speeds, their study would have lead to different conclusions than those presented to the Joint Review Panel.
"They actually got to the point where the bitumen did sink but didn't acknowledge that fact clearly. They should have done a range of tests at different temperatures and wind speeds," Short told The Tyee.
Bitumen is both heavier, thicker and denser than light crude because it is a naturally weathered hydrocarbon that has been heavily degraded by bacteria over millions of years. It also contains a variety of heavy metals (nickel and vanadium) as well as sulfur and nitrogen.
The low-grade crude must be diluted with imported condensate, a gasoline-like product, in order to move through a pipeline.
But the density of bitumen prior to dilution will determine how fast the substance will sink in fresh or salty water. "Yet we only have limited data on a few bitumen products."
In the event of spill on ocean water the condensate would flash evaporate into the air, producing toxic fumes full of carcinogens such as BTEX.
The remaining bitumen would float in highly saline water for a while until it mixed with sediment or plankton that could weigh it down. Such processes would eventually give the substance a density greater than water. Most bitumen varieties are very close to the density of water or "on the edge," explained Short.
Two other issues that bear on Short's study is that the north coast is a place of fierce storms, high winds and heavy seas that greatly increase the risks of a tanker sinking and that, although Enbridge has put in place a small fleet of oil spill recovery vessels, those ships and the booms they use can only be deployed in calm seas.
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