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  • The truth about dilbit

    Katherine Palmer Gordon

    July 2014

    There’s little evidence to support the Joint Review Panel’s critical conclusion that diluted bitumen is “unlikely to sink.”


    WHETHER DILUTED BITUMEN WILL FLOAT on the surface or sink in the ocean, says chemical scientist Thomas King wryly, “is a simple question, but it trails a raft of complex issues.”

    King, based in Halifax, Nova Scotia, is leading Fisheries and Oceans Canada’s research into the behaviour of diluted bitumen under various environmental conditions. “The trouble is,” he says, “that we have very limited information about dilbit’s properties in water. Very little research has been done so far.” 

    Yet, despite the lack of research, the National Energy Board’s Joint Review Panel (JRP) recommended approval of Enbridge’s Northern Gateway Pipeline project (subject to 209 conditions). And on June 17, the federal government did just that.

    The Northern Gateway Pipeline, if completed, will carry 525,000 barrels of diluted bitumen (“dilbit”) daily from Alberta’s oil sands to Kitimat for export to Asia. Kinder Morgan Canada’s expanded Trans Mountain Pipeline is intended to carry another 890,000 barrels of dilbit daily to the Port of Vancouver, also for export. Together, according to Transport Canada, that represents an additional 600 oil-laden tankers a year traversing British Columbia’s coastal waters. 

    The ability to recover dilbit spilled by an errant tanker in these turbulent, rock-strewn waters hangs on the response to that so-called simple question: Does it sink or does it float? 

    The JRP seemed to think it had a simple answer, stating in its report: “The evidence does not indicate that dilbit is prone to sink in the marine environment.” Unfortunately, it would seem that the evidence is nowhere near that clear. If anything, the indications to date suggest that dilbit is prone to sink in the ocean. 

    Either way, two things are clear. We’re a long way yet from getting the information needed to answer the question definitively. And, until we have it, Canada’s ability to respond effectively to any dilbit spill will remain severely impoverished. 

    Canada has experience dealing with surface spills of conventional light oil and has developed techniques to deal with such spills, says King. But those techniques aren’t foolproof by any means. And when dilbit is spilled, he points out: “Standard recovery approaches can’t be used anyway.” Submerged dilbit is much harder to locate and remove. It may be completely irrecoverable in deep water. 

    There is one thing we do know for certain, he adds: “Damage to marine habitat and its living resources [from sinking bitumen] is expected to be much greater.”


    The great sink/float debate

    Conventional light oil typically floats on the surface of water—hence the oily sheen commonly seen around docks, for example. Undiluted bitumen, a form of a heavy, viscous crude oil, is considerably denser (which is why it is sometimes referred to as “heavy oil”). Bitumen deposits are often referred to as “tar sands” because of the thick, sticky texture of the oil. 

    Undiluted bitumen is too thick to transport by pipe. Various types of condensate or light synthetic crude oil are therefore used as diluents. The end product is referred to by the generic term “dilbit” or “synbit,” but there may be dozens of different varieties. No-one knows for sure how many currently exist, however, because the development of new chemical combinations is not only industrial proprietary property, but constantly changing as new research is undertaken.  

    Oil companies, including Enbridge, have typically taken the stance that dilbit floats and therefore doesn’t pose a greater risk to the environment than conventional oil. 

    Alberta-based Crude Quality Inc, for example, reported in 2011 to American authorities in relation to the proposed Keystone XL Pipeline that “under standard conditions,” dilbit will float on water. A 2012 report by Ottawa-based SL Ross Environmental Research Ltd drew a similar conclusion. A year later Dr Alan Maki, a witness for Enbridge at National Energy Board hearings on the Northern Gateway project, told the NEB even more strongly: “It is an immutable fact of physics that [dilbit] will float. It simply cannot sink in water.”

    Independent scientists believe exactly the opposite, however. Dr Merv Fingas, an Edmonton-based environmental physicist, former head of Environment Canada’s oil spill R&D unit and the author of seven books about oil spills, told the Globe and Mail that Maki’s claim was simply “not true.” Fingas added: “Every time we did get a sample of any kind of bitumen in the lab and analyzed it, it always sank.”

    Last year American environmental chemist Dr Jeffrey Short, who assessed the impacts of the 1989 Exxon Valdez spill for the Alaska and US governments, looked into the susceptibility of dilbit to sinking on behalf of Kitkatla’s Gitxaala Nation. Short reviewed previous studies and then assessed that data against the typical rough, windy weather and cold temperature conditions in the Douglas Channel and Hecate Strait. 

    He concluded that those previous studies had failed to take into account these typical conditions. The studies were therefore unreliable at best, and completely invalid in some cases. He also pointed out that testing has taken place on only two dilbit products to date. There are many varieties of dilbit being produced, so to conclude that all dilbit floats based on those tests, stated Short, simply doesn’t add up. In fact, he posited the opposite: “Because…only a very few bitumen products have been evaluated experimentally, it is plausible that other products that might be shipped through the proposed Northern Gateway pipeline might be even more susceptible to sinking.” 

    Short also told The Tyee that he was “mystified” by the lack of available scientific information about dilbit given its importance in analyzing the environmental impact of the Northern Gateway proposal. “On a project of this significance,” he commented to writer Andrew Nikiforuk, “Canadians should go into it with their eyes open and not base your public policy on fantasies.”

    Unfortunately, it seems independent Canadian experts able to speak knowledgeably about dilbit’s buoyancy are thin on the ground on the west coast. The University of Victoria, Simon Fraser University, and the University of British Columbia all failed to identify anyone on faculty with this kind of expertise. The provincial Ministry of Environment admitted that there is also no one within the BC government who can speak to the science. 

    Even Merv Fingas, who was so outspoken on the topic just last year, can apparently no longer speak about the issue. Fingas refused an interview request, writing: “Due to commitments on a particular study I am unable to do that.”


    Unprepared for 600 tankers

    On November 30 last year, the government released a multi-departmental report confirming what King is saying: “The potential range of behaviour, fate and treatment options for a possible marine spill of diluted bitumen products is not well understood. There is little information on the spill behaviour, fate, impacts and remediation options for diluted bitumen spills.” It did, however, note: “When fine sediments were suspended in the saltwater, high-energy wave action mixed the sediments with the diluted bitumen, causing the mixture to sink or be dispersed as floating tarballs.”

    About the same time, Transport Canada released two reports reviewing Canada’s ship-source oil spill and response regime and assessing the risk of spills in Canadian waters south of the 60th Parallel. It made this disturbing admission: “Advances in research and development of response techniques are not captured in the Canadian [response] regime and there has also been a gradual weakening of the regime in other respects. Over time, knowledge and skills sets within Government have eroded…The Commissioner of the Environment and Sustainable Development also identified a number of gaps, largely the result of insufficient data and information collection and analysis.” 

    In other words, despite the push to export oil, the government isn’t even close to being prepared for a conventional oil spill at sea, let alone a dilbit disaster. The reports contain further bad news for west coasters: One of the areas of highest probable risk right now for a crude oil spill over 10,000 tonnes is the area around the southern tip of Vancouver Island. “In the Strait of Juan de Fuca,” notes one report in unequivocal terms, “Canada should be prepared for a spill of crude oil.” 

    What happens when 600 additional oil-laden tankers a year start navigating British Columbia’s wild waters? It would seem neither Transport Canada—nor any other arm of the federal government—has any idea. 

    Only recently, as the result of heavy public pressure, is the issue being taken seriously by the feds. The November 30 report also announced the launch of the coordinated scientific research initiative in which Tom King is participating. In collaboration with DFO, Environment Canada and Natural Resources Canada have begun investigating what may happen in the event of a dilbit spill in Douglas Channel or Hecate Strait. The primary goal of the research initiative is to “improve the preparedness and response for marine spills” of dilbit so that responders can “make informed decisions on the appropriate oil spill response options and strategies.” 

    King’s team is looking not only into whether, how quickly and how far dilbit sinks in water, but also how the heavy oil behaves in different weather conditions; the impacts of salinity, rainfall, wind, sunlight, water temperature and sedimentation; and the environmental impacts of bitumen in different situations. They are also reviewing the effectiveness under water of existing conventional oil recovery techniques and chemical dispersants—all issues that must be understood before effective dilbit recovery methods can be developed. 

    The first phase of the research work isn’t expected to be completed before March 2016. Funding has been provided to continue development of ocean and dilbit behaviour models through to the end of 2018. It’s uncertain whether this is sufficient time for the work to be completed, however. In the meantime, the environmental impacts of a major bitumen spill are still only being guessed at. 

    We do know that three years after the 2010 Deepwater Horizon oil disaster in the Gulf of Mexico, tar balls—sticky, solid pieces of oil that form when water combines with spilled oil and which can travel hundreds of kilometres—could still be found in the coastal marshes of Louisiana. In 2013, it was estimated that approximately 680 million litres of dilbit remained in Michigan’s Kalamazoo River after an Enbridge pipeline burst in 2010, spilling more than three times that amount into the Kalamazoo. Portions of the river still remain closed. 


    The JRP’s conclusions

    Notwithstanding the scientific uncertainty, the JRP was dismissive of evidence suggesting that dilbit will sink, stating: “Although there is some uncertainty regarding the behavior of dilbit spilled in water, the Panel finds that…dilbit is unlikely to sink due to natural weathering processes alone, within the time frame in which initial, on-water response may occur, or in the absence of sediment or other particulate matter interactions. The Panel finds that a dilbit spill is not likely to sink as a continuous layer that coats the seabed or riverbed.”

    The JRP also stated—in contradiction to the concerns expressed by Transport Canada about the negative impact of a lack of scientific information on response capability—“In the Panel's view, the weight of evidence indicates that disagreement among experts on the fate and behaviour of spilled oil is related to specific details that may not be significant from a spill response perspective.” 

    That’s despite the fact that the JRP also admitted it didn’t have enough information: “Additional research is required to answer outstanding questions related to the detailed behaviour and fate of dilbit. All parties with technical expertise on the topic were in agreement with this. The Panel finds that research on the behaviour and cleanup of heavy oils is required to inform detailed spill response planning and heavy oil spill response in marine and freshwater environments.” 

    Condition 167 of the JRP’s approval requires Enbridge to file much more detailed information on spill modelling and response with the National Energy Board at least three years prior to commencing operations. How that might change the JRP’s conclusions remains unclear.


    Federal scientists’ investigations

    Environment Canada, the lead federal agency investigating potential environmental impacts of spilled dilbit, could not “accommodate” a request to interview one of their scientists. Communications staff, however, confirmed: “In certain environmental conditions, dilbit can sink in saltwater environments. In general, how combinations of factors might cause oil to sink is not well known currently. Further research is needed.” 

    DFO did permit Tom King and another of its senior scientists, Sidney-based Dr Charles Hannah, to speak about the latest state of the science on this subject. In Halifax, Tom King has been conducting experiments in flume tanks with two variations of dilbit. “There are several things that are important to understand,” he explains. “Dilbit will float at first, because it is less dense than water. However, lighter diluent material will start to evaporate. You can smell it—it’s the kind of smell you get at a gas station.” Some of the oil will start to dissolve. What remains will be subject to “weathering”—the effects of rain, temperature, sunlight, turbulence, wind, and microbes in the water. 

    “Our tests, which mimic what will happen in a real world environment, indicate that by the sixth day of natural weathering, bitumen will sink.” Other factors may cause it to sink more rapidly. “If it spills in freshwater, bitumen will sink faster because freshwater is less dense than brackish (partly salty) or ocean water. In the Kalamazoo River, parts of the oil sank within four days.” 

    Heavy seas will also make bitumen sink faster. So will the presence of sediment in the water. Many sediment-laden glacial rivers empty into Douglas Channel: “We’re looking at that right now and the impact when bitumen combines with sediment suspended in water,” says King. 

    Where the spill occurs is also critical. In deep water, the oil won’t necessarily sink to the bottom but may instead hit a point of neutral buoyancy where it will remain suspended. In shallower waters, oil will likely coat the ocean floor or riverbed. As we’ve learned from the Kalamazoo River experience, it may be just as difficult to remove in that situation as if it were floating freely in sub-marine waters.

    The next step, King continues, is to use the data being generated by his lab to develop ocean models predicting what will happen in a range of different circumstances. That’s where Charles Hannah comes in. 

    “What we’re doing here at DFO in Sidney,” says Hannah, “is collecting ocean observations on the north coast and building an ocean circulation model that factors in what happens to water movement based on wind, tides, current, weather conditions and so on. That will inform the development by Environment Canada of different oil spill scenarios and remediation methods to deal with different situations. ” 

    In Hecate Strait and the Douglas Channel, says Hannah, ocean conditions vary widely from location to season. “At Kitimat, for example, when the rivers are in full flood there is more freshwater entering the Channel. So at some times of year bitumen might sink faster, or have different neutral buoyancy zones.”

    The problem for the modellers is the same as the one King and other researchers face: a lack of information. Asked what other factors he is taking into account in developing ocean models specific to the north coast, for example, Hannah replied: “We just don’t know yet.” 

    He cites Kitimat again as an example. “It’s the rainfall capital of the world, but what weathering impact does rain have on bitumen? The knowledge may be out there but we don't have it yet. We do know a lot about wave impacts, but the wave environment varies enormously in that area. We need to start to study that too, and its importance. ” 


    Sailing into dangerous waters

    Will dilbit-laden tankers be plying Hecate Strait—one of the most dangerous bodies of water in the world (waves can reach 26 metres)—or indeed Juan de Fuca Strait, already identified as high risk for an oil spill—before all these questions have been answered? 

    Asked to confirm whether current spill response capacity still remains insufficient, Transport Canada replied instead: “As part of new measures for our World Class Tanker Safety System announced on May 13, 2014, the federal government will be implementing Area Response Planning starting in four local areas. Under Area Response Planning, response plans will be tailored to reflect local conditions such as geography, environmental sensitivities, and vessel traffic.”

    It also admitted again that it doesn’t yet have the information it needs: “As well, the Government will be undertaking additional research and development on the behaviour of petroleum products and a range of response measures to quickly and effectively respond to and clean up a marine oil spill, should one occur.” Translation: No, as things stand, we aren’t ready for a spill. 

    Bitumen certainly doesn’t sink if it isn’t permitted to spill in the ocean in the first place, but there appears to be no appetite on the part of the federal government to consider whether dilbit-laden tankers should be allowed in those tempestuous waters in the first place, given the associated risks. Nor, given its acceptance of the JRP’s recommendation to approve the Northern Gateway project, does it seem concerned about the discrepancies between the JRP’s conclusions and the views of several of its own departments. 

    That may change as a plethora of lawsuits challenging the JRP’s findings starts hitting the courts. Joining several other environment groups and dozens of First Nations in attacking the decision, the BC Federation of Naturalists launched its suit within hours of the federal government’s decision. The view expressed by President Kees Visser is typical of the opposition being expressed: “We cannot stand by and allow Cabinet to approve this ill-conceived project on the basis of a JRP report that is so flawed and incomplete.” 

    Even if unsuccessful, the litigation may tie up the process long enough for the vital missing research to be completed and for response capability to be improved. 

    Whether that will be enough is another outstanding question. In the meantime, British Columbians will have to hope that question will only ever have to be answered in theory. 

    Katherine Palmer Gordon is the author of six books of non-fiction, including several BC Bestsellers and a Haig-Brown prize-winner.

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