Water Closet for Nov.18, 2016
OIL AND WATER DON’T MIX
[pullquote]”If increased oil transport in the Gulf of Maine isn’t concerning enough, dilbit happens to differ chemically in a major way from conventional crude oil: it cannot be effectively cleaned up when spilled in water.”[/pullquote] If you have a globe look down at the North Pole from above. View the Arctic, home to about four million people. For tens of thousands years sunlight has reflected off the white polar ice helping to keep our planet cool. The year long ice cap has been a barrier to trade by shorter great-circle routes to the orient. As the polar ice diminishes and more light and heat-absorbing dark open water is exposed, northwest and northeast passages so long sought seem eminently available for profitable short term trade, but not for the health of the planet.
The Working Waterfront monthly newspaper published by The Island Institute in Rockland, Maine, has given the Middleton Stream Team permission to publish the following article from their November 2016 issue. Massachusetts borders the Gulf of Maine.
Oil that doesn’t float – Tar sands oil through Gulf of Maine poses new threat By Heather Deese and Susie Arnold
IT’S HARD TO IMAGINE a heavy tar sands oil spill in the Gulf of Maine. Not just because of the vastness of the ocean and our dependence on clean water for our fisheries economy, but also because tar sands oil is mined and steamed from the ground thousands of miles away.
However, there is a proposal in the works in Canada to build a pipeline all the way from the tar sands deposits in northern Alberta to Saint John, New Brunswick, through which tar sands oil, in this case bitumen (known in the biz as “dilbit”), would be transported. An estimated 281 oil super tankers per year would then transit the Bay of Fundy and the Gulf of Maine, delivering primarily dilbit to the refineries of the Mid-Atlantic and the Gulf Coast regions, essentially creating a floating pipeline over the nation’s most productive fishing grounds and critical habitat for marine life.
If increased oil transport in the Gulf of Maine isn’t concerning enough, dilbit happens to differ chemically in a major way from conventional crude oil: it cannot be effectively cleaned up when spilled in water. Dilbit is a manufactured combination of extra-heavy bitumen, with the consistency of peanut butter at room temperature, and a much less viscous diluent. The mixture allows it to be moved through pipelines, but most of the diluents used are highly volatile. Immediately following a spill, rapid evaporation of the diluent can produce a dense residue in a day or so.
Conventional crude oil behaves differently. Its light components evaporate more slowly and the eventual residues are seldom as dense as those resulting from tar-sands bitumen. Particularly when residues are mixed with sand or silt, dilbit residues are far more prone to sink than are residues of conventional crude oil. Also its ability to stick to other objects, or its “adhesion,” is up to 100 times greater that that of conventional oils. Thus, sticky, tar sands oil with its propensity to sink, poses a substantial, long term risk to the life on the sea floor.
The important point for coastal communities adjacent to the potential transit route of dilbit is this: spill response techniques for non-floating oil in water are inadequate. This is one conclusion of the National Academies of Sciences, Engineering, and Medicine report, “Spills of Diluted Bitumen from Pipelines: A Comparative Study of Environmental Fate, Effects and Response,” published earlier this year.
Several factors complicate the response to a diluted bitumen spill. Immediately after a spill, weathering (the physical and chemical changes in spilled oil) happens quickly and the window during which dispersants, burning or containment techniques for responding to oil that has sunk to the bottom have variable effectiveness. . .” Add to this the complicating factor of mustering a response in the open ocean environment, and those recovery and containment techniques look even less feasible.
Dr. John Hayes, an author on the report, noted “Even if we were totally prepared to clean up a conventional oil spill, this is a different matter and bears reconsideration of our preparedness.”
Hayes and organic chemist and marine scientist and member to the National Academy of Sciences, pointed to lessons learned from the spill in Michigan’s Kalamazoo River where dilbit residues sank much more rapidly than spill crews expected. It took years to clear the bottom of waterways there.
We don’t have much experience with the dilbit spills in the marine environments, not because of an exceptional safety record, but because there isn’t much transport of dilbit over the ocean. The Exxon Valdez and the Deepwater Horizon spilled conventional crude oil. And in the case of Alaska’s Prince William Sound, over 27 years later, crude oil can still be found buried in the sands of many beaches. Burnaby, British Columbia and Santa Barbara, California, both have had instances of heavy oil reaching coastal zones, but only in estuaries or very shallow coastal waters, allowing response strategies such as vacuuming, booming and manual removal to be immediate and somewhat effective. In both cases, even with the spill confined to near shore, sunken and submerged oil adhered to kelp beds and near shore reefs.
Clean-up approaches for spilled dilbit are based on conventional floating crude oil, and there is no known effective technique for recovery of submerged crude oil, especially in the offshore environment. Particularly for people in the region who rely on clean water for their livelihoods, the proposed pipeline and shipping of dilbit through the Gulf of Maine is worth tracking.
Dr. Heather Deese is the Island Institute’s vice president of research and strategy. Dr. Susie Arnold is an ecologist and marine scientist with the organization.
WATER RESOURCE AND CONSERVATION INFORMATION FOR MIDDLETON, BOXFORD AND TOPSFIELD`
|Precipitation Data* for Month of:||Aug||Sep||Oct||Nov|
|30 Year Normal (1981 – 2010) Inches||3.37||3.77||4.40||4.55|
|2016 Central Watershed Actual||2.14||1.85||6.81||0.2**as of Nov 10|
Ipswich R. Flow Rate (S. Middleton USGS Gage) in Cubic Feet/ Second (CFS):
For Nov 10, 2016 Normal . . . 30 CFS Current Rate . . .10 CFS
*Danvers Water Filtration Plant, Lake Street, Middleton is the source for actual precipitation data thru Oct.
** Middleton Stream Team is the source of actual precipitation data for Nov.
Normals data is from the National Climatic Data Center.
THE WATER CLOSET is provided by the Middleton Stream Team: www.middletonstreamteam.org or <MSTMiddletonMA@gmail.com> or (978) 777-4584