As this report demonstrates, diluted bitumen has unique properties that differentiate it from commonly transported crude oils. Because of these properties, diluted bitumen’s behavior in the environment following a spill is different from that of the light and medium crudes typically addressed in spill response planning, preparedness, and response. Of most significance are the physical and chemical changes that diluted bitumen undergoes as a result of weathering. When the diluent component volatizes, the remaining bitumen becomes denser and, depending on circumstances, may aggregate with particles in the water column and remain in suspension or sink to the bottom of a water body. The submergence of persistent residues of diluted bitumen in aquatic environments, as was seen in the Marshall, MI spill, and the potential for long-term deposition in sediments and banks and remobilization in the water column present environmental concerns and cleanup challenges not presented by commonly transported crude oils. These challenges necessitate different response strategies, including immediate efforts to recover spilled diluted bitumen before significant weathering occurs and effective methods to identify, contain, and recover suspended and sunken oil.
The existing framework for pipeline spill planning, preparedness, and response is generally designed to address floating oil and not residues that mix throughout in the water column, aggregate with particles, and sink to the bottom of aquatic environments. As a result, the pipeline operators and the agencies responsible for spill planning and response may not be adequately prepared for diluted bitumen spills and may
lack the tools for effective cleanup. This is in part a shortcoming of the Pipeline and Hazardous Materials Safety Administration (PHMSA) Part 194 regulations and in part a shortcoming of the broader interagency contingency planning and response system. A more comprehensive and focused approach to diluted bitumen across the federal oil spill response family is necessary to improve preparedness for spills of diluted bitumen and to enable more effective cleanup and mitigation measures when these spills occur. The recommendations presented in this chapter are designed to achieve this goal.
Recommendation 1: To strengthen the preparedness for pipeline releases of oil from pipelines, the Part 194 regulations implemented by PHMSA should be modified so that spill response plans are effective in anticipating and ensuring an adequate response to spills of diluted bitumen. These modifications should
- Require the plan to identify all of the transported crude oils using industry-standard names, such as Cold Lake Blend, and to include Safety Data Sheets for each of the named crude oils. Both the plan and the associated Safety Data Sheets should include spill-relevant properties and considerations.
- Require that plans adequately describe the areas most sensitive to the effects of a diluted bitumen spill, including the water bodies potentially at risk.
- Require that plans describe in sufficient detail response activities and resources to mitigate the impacts of spills of diluted bitumen, including capabilities for detection, containment, and recovery of submerged and sunken oil.
- Require that PHMSA consult with the U.S Environmental Protection Agency (USEPA) and/or the U.S. Coast Guard (USCG) to obtain their input on whether response plans are adequate for spills of diluted bitumen.
- Require that PHMSA conduct reviews of both the completeness and the adequacy of spill response plans for pipelines carrying diluted bitumen.
- Require operators to provide to PHMSA, and to make publicly available on their websites, annual reports that indicate the volumes of diluted bitumen, light, medium, heavy, and any other crude oils carried by individual pipelines and the pipeline sections transporting them.
- Require that plans specify procedures by which the pipeline operator will (i) identify the source and industry-standard name of any spilled diluted bitumen to a designated Federal On-Scene Coordinator, or equivalent state official, within 6 hours after a spill has been detected and if requested, (ii) provide a 1-L sample drawn from the batch of oil spilled within 24 hours of the spill, together with specific compositional information on the diluent.
These recommended changes in the Part 194 regulations would take important steps to ensure that spill response plans recognize the differences between diluted bitumen and commonly transported oils and that pipeline operators and agency responders have the special expertise, capabilities, and cleanup tools necessary for effective responses to spills of diluted bitumen.
Critical to effective planning and response is determining whether a pipeline segment is expected to transport diluted bitumen and, if so, identifying its cleanup-relevant properties (e.g., density, adhesion, viscosity, and biodegradability) before and after weathering. This should be accomplished by requiring spill response plans to provide industry-standard namesi for the crude being transported, accompanied by a relevant properties description. This information would also be required in the Safety Data Sheet (SDS), which would be submitted to PHMSA for review as part of the response plan. The SDS is an important vehicle for communicating response information to affected persons who may not receive the formal response plan, such as local communities, fire departments, and medical personnel. A clear and specific description of the crude being spilled is critical to perform this informational function.
The response plans should also demonstrate that the operator understands the unique properties and potential environmental impacts of diluted bitumen and is prepared to implement response strategies that address its challenges. This should take the form of enhanced plan sections describing in detail (i) the areas most sensitive to the effects of a diluted bitumen spill, including the water bodies potentially at risk, and (ii) response strategies and resources necessary to mitigate the impacts of spills of diluted bitumen, including capabilities for detection, containment, and recovery of submerged and sunken oil.
The regulations should provide that PHMSA will review these plan elements not simply to determine whether the plan is complete (the current “checklist” approach) but also to examine whether the plan is adequate and effective in anticipating and preparing for a diluted bitu-
i The industry-standard names should be agreed by both the industry and the relevant government regulators and responders.
men spill. This approach would be a significant change in how PHMSA interprets its responsibilities under OPA 90. Thus, PHMSA would need to reexamine its legal authority to determine whether it has discretion to conduct an adequacy review of plans submitted by pipeline operators.
The PHMSA regulations should also provide that, in conducting such an adequacy review, PHMSA will routinely share the plan with USEPA and USCG and obtain their feedback. This consultation will take advantage of the on-the-ground spill response expertise and experience of these agencies (which PHMSA lacks because it has no direct role in the response process), thus bringing it to bear in examining the adequacy of plans in preparing for diluted bitumen spills.
Requiring submission of annual reports by pipeline operators documenting the volumes of various crudes being transported and the pipeline routes and sections carrying them will fill a fundamental gap in publicly available information and enable responders and communities to be more knowledgeable about the types of spills that might impact their areas and the potential consequences. This will facilitate better planning at the area, regional, and national levels and encourage more informed public engagement.
Finally, while the identification of diluted bitumen and other crudes by industry-standard names should be sufficient in the response plan and SDS, more detailed compositional information will likely be needed when a spill occurs, both to guide the emergency response as well as over the longer term to support forensic chemistry evaluations and site remediation. Given that compositions of oils carried in pipelines typically vary over time, and in the case of diluted bitumen the diluent may be particularly variable, there should be an expedited procedure for characterizing the specific composition of spilled crude oil after a spill. Crude oils transported by pipelines are routinely sampled and the samples are temporarily archived until the shipments are delivered to their final destinations in case questions about the quality of the delivered oil arise at refineries. The regulations should require that, in the event of a spill, sample(s) of crude oil from the archived set representing the spilled oil will be made available within 24 hours to the responsible government agency if requested. The 24-hour time period includes transit time from the origin of the line, which may be thousands of miles away. A minimum volume of 1-L should be sufficient for chemical analysis. Pipeline operators already maintain a custodial sample and the processes are already in place for the collection and storage. The chemical analysis from the crude oil sample will give the composition of the crude oil being transported, which will benefit critical early decisions responding to spills of crude oil. In addition, the operator should be required to inform the relevant authorities of the source and industry-standard name of any spilled diluted bitumen within 6 hours of
a spill being detected. The 6-hour time period was selected as a reasonable balance between the usefulness of the information to the response efforts and the ability of an operator to obtain the information. Because of the potential for submergence within a relatively short window, it is critical that this information be provided to the response community with enough time to act. On the other hand, because transmission pipelines operate in batch shipments, it will take some time for the operator to conclusively identify the specific batch that was spilled.
Recommendation 2: USEPA, USCG, and the oil and pipeline industry should support the development of effective techniques for detection, containment, and recovery of submerged and sunken oils in aquatic environments.
Spills of diluted bitumen products where the crude oil submerges in the water column or sinks to the bottom are particularly difficult for responders. Most of the effective response methods are based on the premise that the spilled oil floats. Proven methods are needed so that responders have effective means by which to determine where the crude oil is, track its movement over time, and effectively recover it. Detection of diluted bitumen spills on the bottom may pose different challenges than for conventional nonfloating crude oils because the diluted bitumen can occur as oil-particle aggregates that require different detection methods than those used to detect bulk crude oil on the bottom. In situations where water is moving, there are no proven techniques for containment of suspended or sunken crude oil to prevent remobilization and spreading prior to recovery. Various techniques have been proposed but few have been shown to be effective. Once the crude oil has sunk to the bottom, recovery methods are selected based on the environmental setting, amount and distribution of the crude oil, and cleanup endpoints. Better technologies are needed to minimize water and sediment removal and improve the separation and treatment of oil, water, and sediment.
Recommendation 3: USEPA, USCG, and state and local agencies should adopt the use of industry-standard names for crude oils, including diluted bitumen, in their oversight of oil spill response planning.
A common nomenclature for identifying diluted bitumen and other crudes should be used across the federal response family and by state and local responders to improve communication and ensure that respond-
ers have accurate and detailed information about the composition of the crude oil being spilled. This is particularly important for diluted bitumen, which has unique and potentially variable properties not fully recognized by the federal response community that need to be clearly identified at the time of a spill. In addition, a common nomenclature system will have benefits for spills of other crude oils as well. This system of product names, which would be incorporated in response plans under Recommendation 1, should be developed through a collaborative process among PHMSA, USEPA, USCG, and state and local agencies and then be adopted by all agencies.
Recommendation 4: USCG should revise its oil-grouping classifications to more accurately reflect the properties of diluted bitumen and to recognize it as a potentially nonfloating oil after evaporation of the diluent. PHMSA and USEPA should incorporate these revisions into their planning and regulations.
USCG categorizes oils into groups defined by their specific gravity, with Group IV oils defined as having a specific gravity equal to or greater than 0.95 and less than 1.0 and Group V oils as having a specific gravity equal to or greater than 1.0. These groups are important because they are used in Oil Spill Removal Organization classifications and setting of guidelines for response capabilities. Under the current approach, diluted bitumen oil products would be classified as Group IV because the fresh oil has a specific gravity less than 1.0. However, once spilled, weathering and loss of the diluent will result in a bitumen with a specific gravity that could approach or become greater than 1.0. The 2013 OSRO Guidelines lack guidance for nonfloating oils in terms of response and transportation and the USCG is in the process of creating a nonfloating oil classification system. Some oils, such as diluted bitumen, have unique characteristics that may cause an evolution from a Group IV oil to a potentially submerged oil (even if not surpassing a specific gravity of 1.0, as in the case of oil-particle aggregates formed in fresh water). A revised USCG classification system can better address these types of oils and should be incorporated in USCG, USEPA, and PHMSA regulations and strategies.
Recommendation 5: The National Oceanic and Atmospheric Administration (NOAA) should lead an effort to acquire all
data that are relevant to advanced predictive modeling for spills of diluted bitumen being transported by pipeline.
A combination of information from oil property and behavior testing, as well as from oil spill models, can improve the response to an oil spill. Accurate spill modeling is now a very important part of both contingency planning and actual spill response. Spill models combine the latest information on oil fate and behavior with hydrodynamic modeling to predict where the oil will go and how much it will change before it arrives. The movement of crude oils is predicted by using the water current and wind speeds along the predicted water path. In addition to predicting the movement, these models can estimate the amount of evaporation, the possibility of emulsification, the amount of dissolution and subsequent movement of the dissolved component, the amount and fate of the portion that is naturally dispersed, and the amount of oil deposited and remaining on shorelines.
In the United States, much of the behavior and weathering information for spills in water is provided by NOAA via their Automated Data Inquiry for Oil Spills (ADIOS) oil weathering model. The NOAA Office of Response and Restoration, which developed and maintains ADIOS, has a mandate to support oil spill response, whereas other agencies do not have the base funding to do the same kind of work. This oil spill response tool models how different types of oil weather in the marine environment. The success of NOAA’s ADIOS is due to their extensive database of more than a thousand different crude oils and refined products. However, the NOAA databases would benefit from additional information on all diluted bitumen products. Data on diluted bitumen that are relevant to the NOAA databases are typically found in bulk form and are currently available through Environment Canada databases and other resources. NOAA should lead an effort to fill this gap.
Recommendation 6: USEPA, USCG, PHMSA, and state and local agencies should increase coordination and share lessons learned to improve the area contingency planning process and to strengthen preparedness for spills of diluted bitumen. These agencies should jointly conduct announced and unannounced exercises for spills of diluted bitumen.
Improved coordination and communication among the many agencies with spill responsibilities would be valuable in creating stronger awareness of the response challenges posed by diluted bitumen, its
unique properties, and the most effective strategies and resources for addressing diluted bitumen spills. There are several vehicles for enhanced collaboration but the area contingency planning process is particularly important because it encourages a focus on the pipeline routes, types of crude being transported, and sensitive water bodies and ecosystems potentially impacted by spills in a defined area. Through the ACP process, plan reviewers and responders can share information gleaned from diluted bitumen response actions, better integrating these two aspects of the response effort. Strong PHMSA participation in area and regional planning, which generally has not occurred up to now, is essential for this collaboration to succeed.
The committee’s understanding is that plan exercises, which are critical to evaluate plan adequacy and responder preparedness, have devoted little if any attention to diluted bitumen spills. USEPA, USCG, and PHMSA together with state and local partners should work together to ensure that announced and unannounced exercises include diluted bitumen spill scenarios so that agencies and pipeline operators can obtain feedback and experience regarding the adequacy of plans for these spills and improve response capabilities.
Recommendation 7: USEPA should develop a standard for quantifying and reporting adhesion because it is a key property of fresh and weathered diluted bitumen. The procedure should be compatible with the quantity of the custodial sample collected by pipeline operators.
As highlighted by Table 2-6, diluted bitumen, and particularly its weathered residues, are highly adhesive. The amount of diluted bitumen residue that will adhere to a clean needle is more than 100-fold greater than the amount that adheres when a clean needle is immersed in the residue of a weathered light, crude oil. Reduction of uncertainties about the chemical cause of diluted bitumen’s avid adhesion, and development of a method that quantifies adhesion precisely, would be useful in tailoring optimal cleanup procedures.
A limited study of the mechanism of adhesion, perhaps by analysis of the materials that adhere to surfaces (as opposed to analyses of the whole oils), should be used to inform the development of a method of adhesion measurement that will provide information not otherwise available to the spill response community and which can be well standardized.
As outlined throughout this report, many differences between diluted bitumen and commonly transported crudes are well established. While there are clearly enough data and information to support the findings and recommendations outlined herein, a more comprehensive understanding of diluted bitumen and its properties, environmental, and human health effects, would improve spill response in the future. There still remain areas of uncertainty that hamper effective spill planning and response. These uncertainties span a range of issues, including diluted bitumen’s behavior in the environment under different conditions, its detection when submerged, and the best response strategies for mitigating the impacts of submerged oil. Because of their importance to spill planners and responders, a concerted effort to fill these knowledge gaps with additional research is essential.
Further research is needed to better understand the behavior of diluted bitumen in the environment, including consideration of the diversity of environmental settings in which spills could occur, the chemical constituents and their toxicological effects, as well as to develop more effective methods for detection and recovery of spilled diluted bitumen, particularly after it becomes submerged or sunken in water bodies. Some of these research needs have been articulated in the past, including a report from the National Coastal Research Council (on behalf of USCG) entitled “Spills of Nonfloating Oils: Risk and Response,” which included specific recommendations for detection, monitoring, modeling, and recovery of submerged oil; however this report focuses mainly on marine environments and did not consider the particular characteristics of diluted bitumen. The recent and projected future escalation of diluted bitumen transport in pipelines (and by other modes) has increased the possibility of release, and therefore research on the effects of diluted bitumen spills on the environment has become an ever more pressing need. Major questions targeted for research include the following:
Transport and fate in the environment. How will the various combinations of bitumen and diluent change (weather) upon release, and can we predict when submergence is likely under a variety of conditions (turbulence, suspended matter, contact with benthic surfaces, plants, etc.)? How does biodegradation influence toxicity, for example, by “releasing” previously bound chemical constituents or by producing more toxic biodegradation products?
Ecological and human health risks of weathered diluted bitumen. While much is known about the toxicity of hydrocarbon components in the commonly used diluents (e.g., benzene), there has been little study of the potential toxicity of bitumen to people or wildlife. For submerged and sunken oil in particular, there may be routes of exposure that have not
been considered sufficiently, such as sensitive egg and larval life stages of fishes, and exposures may occur over protracted periods given the apparent resistance of bitumen components to biodegradation. Other indirect effects of the oil may relate to enhanced bioavailability of co-occurring pollutants and altering properties of the impacted ecosystem (i.e. redox status, dissolved oxygen levels and pH).
Detection and quantification of submerged and sunken oil. The Marshall, MI oil spill demonstrated that current options for sunken oil quantification are either unreliable (e.g., total petroleum hydrocarbons) or very expensive and time consuming (chemical fingerprinting), and consequently “poling” to disturb the sediments and observe the resultant appearance of floating globules and sheen became the primary means of mapping sunken oil (Box 3-1). Better measurement techniques should be a research priority.
Techniques to intercept and recover submerged oil on the move. Submerged oil moving downstream in rivers or following wind- or tidally driven currents could be intercepted in theory, but in reality no techniques are known to be efficacious to capture oil beneath the water surface. Research should strive to develop options for the diversity of environmental settings in which oil can be spilled.
Alternatives to dredging to recover sunken oil. Dredging is costly and environmentally destructive, producing voluminous waste that often must be landfilled, and therefore alternatives should be sought. Agitation and collection of resultant floating oil was conducted in the Kalamazoo River, but its efficacy in a particular spill needs investigation before being deployed again. Other alternatives should be studied as well.
These research priorities are targeted broadly to the research community, but a specific mention is needed regarding the role of local and regional scientists in spill response.117 Improved access and collaboration with these scientists would help advance the scientific understanding of how oil behaves in the environment, particularly for emerging issues such as spills of diluted bitumen. Scientists from outside the formal response framework are typically not included in the formal oil spill response activities and, as a result, are often barred from site access by response officials, and their requests for source materials are denied. This situation hinders fundamental research on spill events—research that should ultimately benefit spill planning—and may also provide immediate benefit to response officials.
Diluted bitumen has received extensive publicity in the past 5 years and will continue to be of interest due to production from Canadian oil
sands. As more diluted bitumen is transported, the need for efficient spill response planning, preparedness, and cleanup will be increasingly important. It is difficult to be completely prepared for a potential spill of diluted bitumen because our experience is limited to just a few significant spills, the products involved can vary in chemical composition, and the environmental settings where spills could occur are extremely diverse. Nonetheless, the recommendations put forward are designed to improve current oil spill planning and response to reduce negative impacts on human health and the environment.