EmergWest Consulting Trans Mountain Expansion Project Containment 1 March, 2015 Summary This report was undertaken, at the request of the Shxw'owhámel First Nation and Peters Band, to consider the possible impacts of a crude oil spill from the proposed Trans Mountain Expansion Project (TMEP) pipeline expansion project. Specifically, this report was to include a review of the materials provided by TMEP in their application, with a specific view of the fate (how oil will age and spread when spilled) and the oil spill prevention and response measures proposed by TMEP. The report is divided as follows: 1. Human/Health Affects 2. Evacuation of Residents 3. Affects to Groundwater 4. Incident Command System (ICS) Training for First Nations Personnel 5. Oil Spill Response Equipment 6. Spilled Oil Fates 7. Spilled Oil Trajectories 8. Submerged/Sinking Oil 9. References Because of the significance of the potential for spilled crude to submerge or sink, a considerable part of the report is dedicated to understanding how and why some oils sink, and the current state of countermeasures if they do, including a case study of the Enbridge Line 6b incident in Marshall, MI, USA. Generally, the TMEP submission, while extensive, lacks key details in terms of many of the various model inputs (and outputs), and relies on the Gainford Study, which, because it does not consider fresh or sediment‐laden water spills, is largely irrelevant for predicting spilled oil fates in the areas important to the Shxw'owhámel First Nation and Peters Band. While this report focuses on the potential direct affects to the two First Nations (FN), additional input is provided on the various submissions that, while not directly applying to the FN areas, have broad response implications in all spill conditions and locations. While generally spills from pipelines are infrequent, there remains a chance of a spill that could affect the immediate health and safety of the Shxw'owhámel First Nation and Peters Band, as well as long‐term affects to both their traditional territories and Reserves.
The potential impacts a marine oil spill would have in Shxw’ōwhámel territory.
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EmergWest Consulting Trans Mountain Expansion Project
Containment 1 March, 2015
Summary
This report was undertaken, at the request of the Shxw'owhámel First Nation and Peters Band,
to consider the possible impacts of a crude oil spill from the proposed Trans Mountain Expansion
Project (TMEP) pipeline expansion project. Specifically, this report was to include a review of the
materials provided by TMEP in their application, with a specific view of the fate (how oil will age
and spread when spilled) and the oil spill prevention and response measures proposed by
TMEP.
The report is divided as follows:
1. Human/Health Affects
2. Evacuation of Residents
3. Affects to Groundwater
4. Incident Command System (ICS) Training for First Nations Personnel
5. Oil Spill Response Equipment
6. Spilled Oil Fates
7. Spilled Oil Trajectories
8. Submerged/Sinking Oil
9. References
Because of the significance of the potential for spilled crude to submerge or sink, a considerable
part of the report is dedicated to understanding how and why some oils sink, and the current
state of countermeasures if they do, including a case study of the Enbridge Line 6b incident in
Marshall, MI, USA.
Generally, the TMEP submission, while extensive, lacks key details in terms of many of the
various model inputs (and outputs), and relies on the Gainford Study, which, because it does
not consider fresh or sediment‐laden water spills, is largely irrelevant for predicting spilled oil
fates in the areas important to the Shxw'owhámel First Nation and Peters Band.
While this report focuses on the potential direct affects to the two First Nations (FN), additional
input is provided on the various submissions that, while not directly applying to the FN areas,
have broad response implications in all spill conditions and locations.
While generally spills from pipelines are infrequent, there remains a chance of a spill that could
affect the immediate health and safety of the Shxw'owhámel First Nation and Peters Band, as
well as long‐term affects to both their traditional territories and Reserves.
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1 Human/HealthImpacts
CrudeOilVapourExposuretoResidents
Due to the proximity of the pipeline, and the projected paths (see Section 7) of any spilled
crude oil, it is possible that flammable and/or toxic vapour concentrations could form in air,
thus directly affecting the Peters or Shxw'owhámel First Nations (in the event of a nearby
release), or limiting their ability to safely leave the affected area.
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1.1 PotentiallyFlammable/ExplosiveVapours
Crude oils emit vapours that, if they reach a sufficient concentration in air, can ignite, and if
those expanding vapours meet resistance, can explode. Pure chemicals have very well‐
understood ranges in which these vapours can form flammable mixtures in air. The minimum
amount of fuel in air that can form a flammable mixture is called the Lower Explosive Limit
(LEL). The upper limit, which if exceeded would be too rich, is called the Upper Explosive Limit
(UEL). The range of vapour mixtures (from LEL to UEL) that can ignite is called the flammable
range.
The lower explosive limit of most crude oils is around 1.5% in air. As an example, Cold Lake
Blend (CLB), based on the crudemonitor.com web site, includes numerous constituents (see
Figure 1.1) which include Benzene (LEL of 1.35%), Pentane (LEL of 1.4), Hexane (LEL of 1.1), and
Heptane (LEL of 1.0).
Figure 1.1
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If a CLB spill were to occur, then the Lower Explosive Limit would be approximately 1.5% (fuel in
air). It should be noted that oil spill responders (when responding to crude oil spills) normally
calibrate their vapour monitors using pentane (LEL of 1.4) in order to mimic the anticipated
vapours, thus providing additional support to the following calculations:
The LEL of CLB (1.5 % fuel in air) expressed as a decimal = 0.015
The LEL expressed in parts per million (ppm) = 15,000 ppm
10% of the LEL = 1,500 ppm
A number of models were developed by the author (see Section 1.3.4) to try determine the
potential extent of a vapour plume from a crude oil spill. The model outputs depict the possible
vapour plumes (total hydrocarbons) one hour after a CLB crude oil release near each of the
Shxw'owhámel and Peters Reserves. The blue plume (see Figures 1.7 and 1.8), stretching
approximately 800 m, depicts a range of total hydrocarbons of from 10,000 – 100,000 ppm
(with the high end of the range occurring closer to the source). While these highly‐volatile
vapours are typically transient (they will deplete relatively quickly, usually within a few hours),
there is still potential for potentially‐flammable vapours to form in air, and for those vapours to
drift across HWY 1, the railroad tracks, and to disallow the safe egress out of the affected
Reserves (and the safe ingress for responders).
Further, emergency responders, equipped with vapour monitors are trained to leave the area
immediately if they encounter readings exceeding 10% of the Lower Explosive Limit (for
precautionary safety reasons).
The dark green plume (which stretches approximately 2.5 km) includes a concentration equal to
10% of the LEL, and would not only cross the highway and the rail tracks, but would extend well
beyond the only egress routes (of either affected First Nation), and would reach the homes of
the band members. Again, the potential vapour clouds could, at least for a time, prevent band
members from escaping the area, and could also prevent emergency responders from entering
the area to provide assistance to band members.
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1.2 PotentiallyToxicVapours
Crude oils, due to their complex makeup, can emit a wide range of potentially poisonous (toxic)
vapours. These can include Hydrogen Sulphide (H2S), a vapour which is heavier that air, and is
known to, at higher concentrations, pose potentially‐serious (and life‐threatening) hazards.
Other vapours typically emitted from evaporating crude oils include Benzene, Toluene, Ethyl
Benzene, and Xylene (commonly called BTEXs). Of these, Benzene is considered the most
dangerous, as it is a known carcinogen (the others are suspected carcinogens).
While there are no set limits for exposure to benzene, the US Environmental Protection Agency
states:
Neurological symptoms of inhalation exposure to benzene include drowsiness, dizziness,
headaches, and unconsciousness in humans. Ingestion of large amounts of benzene may
result in vomiting, dizziness, and convulsions in humans. (1)
Exposure to liquid and vapor may irritate the skin, eyes, and upper respiratory tract in
humans. Redness and blisters may result from dermal exposure to benzene. (1,2)
Animal studies show neurologic, immunologic, and hematologic effects from inhalation
and oral exposure to benzene. (1)
Tests involving acute exposure of rats, mice, rabbits, and guinea pigs have demonstrated
benzene to have low acute toxicity from inhalation, moderate acute toxicity from
ingestion, and low or moderate acute toxicity from dermal exposure. (3)
The reference concentration for benzene is 0.03 mg/m3 based on hematological effects
in humans. The RfC is an estimate (with uncertainty spanning perhaps an order of
magnitude) of a continuous inhalation exposure to the human population (including
sensitive groups) that is likely to be without appreciable risk deleterious non‐cancer
effects over a lifetime. (4)
The modelling conducted by TMEP shows potentially‐dangerous vapour plumes drifting as far
as 1‐2 km from the spilled crude (see below, from Volume 7 Part 12 – Oil Spill Study).
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Figure 1.2
The contour shown in Figure 1.2 depicts a benzene concentration in air of up to 1,000 µg/m3
(approximately 0.3 ppm) reaching almost 1 km. Unfortunately, the model output above does
not include any details of:
The crude oil modelled
The volume of oil
The pooled oil thickness or area
The wind speed
Although these is no limit for exposure for benzene, the Time‐Weighted Average (TWA)
threshold for workers (the level at which responders would don respiratory protection) is 0.5
ppm.
Since the TMEP model did not include any details on the parameters that resulted in the output
in Figure 1.2, a number of models were run by the author using various Alberta‐sourced diluted
bitumen crudes (dilbits) and synthetic bitumen crudes (synbits), under a number of conditions
in order to try to characterize the range of potential impacts from evaporating vapours from a
potential crude oil spill in proximity to either the Shxw'owhámel First Nation or Peters Band.
These are included in Section 1.3.
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1.3 AirMapVapourModelling
The vapour plume modelling conducted as part of this study used AirMap, and was developed
by RPS ASA (which has provided oil spill and related modelling and software since 1979, and is
widely‐recognized as an industry leader) AirMap is an atmospheric dispersion model designed
to predict the trajectory and fate of a wide variety of chemical substances and biological agents
in the atmosphere. The model uses physical and chemical properties, such as vapor pressure
and environmental degradation rates, to predict the fate of substances that have been released
into the atmosphere.
The mass is dispersed horizontally by turbulence, either using a user‐input constant rate
(horizontal dispersion coefficient) or following the algorithm from Gifford (1961), as described
in Csanady (1973). The model‐calculated horizontal dispersion coefficient is a function of wind
speed and air stability. Stability is defined as:
Moderately stable
Slightly stable
Neutral
Slightly unstable
Moderately unstable
The US EPA and NOAA (2002) offers the following guidance (based on Turner, 1970) in the
Aloha model regarding atmospheric stability:
“The atmosphere may be more or less turbulent at any given time, depending on the
amount of incoming solar radiation as well as other factors. Meteorologists have defined six
atmospheric stability classes, each representing a different degree of turbulence in the
atmosphere. When moderate to strong incoming solar radiation heats air near the ground,
causing it to rise and generating large eddies, the atmosphere is considered ‘unstable’, or
relatively turbulent. Unstable conditions are associated with atmospheric stability classes A
and B. When solar radiation is relatively weak, air near the surface has less of a tendency to
rise and less turbulence develops. In this case, the atmosphere is considered ‘stable’, or less
turbulent, the wind is weak, and the stability class would be E or F. Stability classes D and C
represent conditions of more neutral stability, or moderate turbulence. Neutral conditions
are associated with relatively strong wind speeds and moderate solar radiation.”
Stability class has a big effect on the modeled dispersion of a gas. Under unstable conditions,
for example, a dispersing gas will mix rapidly with the air around it and the pollutant will be
diluted more quickly below levels of concern then it would for more stable conditions.
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1.4 AirMapModelInputs
The key model inputs used in the AirMap model were the simulation length, crude oil, volume
and spill duration, wind speed and direction, and the various model‐specific criteria.
1.4.1 ModelLocationandSimulationLength
Models were run based using a relatively short duration (2 hours), due to the proximity of the
pipeline to the two Reserves.
Figure 1.3
1.4.2 ModelOil,VolumeandSpillDuration
The crude oil simulated in the models was Cold Lake Blend, at a relatively conservative estimate
of 200 m3. The models were run for 2 hours (the output shown is after 1 hour).
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Figure 1.4
1.4.3 ModelWinds
The winds chosen for the models represents a worst‐case scenario, i.e., light winds (4 knots)
from the SE. The light winds would cause the vapours to drift towards the Reserves, with little
dispersion (reduction in concentration).
Figure 1.5
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1.4.4 AirMapModelParameters
The model parameters chosen were the defaults provided with the model. The shortest
possible time step (1 minute) was used, and the 3D dispersion was calculated by the model. An
open country ground roughness was chosen to best‐represent the area.
Figure 1.6
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1.4.5 AirMapModelOutputs
The model outputs below depict the possible vapour plumes (total hydrocarbons) one hour
after a CLB crude oil release near the Shxw'owhámel and Peters Reserves.
Figure 1.7
Figure 1.8
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1.4.6 PotentialImpactsfromVapours
Based on the example vapour plumes shown in 1.7 and 1.8, the potential down‐wind distance
that could be affected could extend to the First Nations’ egress routes, and in some cases, to
their homes.
If benzene represents as little as 0.1% of the total crude oil (this is typical of many Canadian
Synthetic crudes), then the blue plume contour (from Figures 1.7 and 1.8) represents a range of
10 to 100 ppm of benzene.
Further, if spilled crude oil spreads down‐current, as is predicted by the TMEP models (see
Section 7), there is a real likelihood that residents of either of the affected First Nations would
be well within the corridor of potentially‐toxic or flammable concentrations (or at least
concentrations which could limit the ability of responders to provide support to affected band
members).
Even in a best‐case scenario, it is highly‐unlikely that responders could stop, either the spread
of crude oil, or its evaporating vapours, before it would affect the Reserves. As such, it is
critically important to know what measures TMEP will take to ensure the safety of the Peters
and Shxw'owhámel First Nations in the event of a spill in the area.
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2 Evacuation
There is only one road into/out of the Shxw'owhámel Reserve. Similarly, there is one primary
road, which splits into two exits (one for each direction of the highway), into and out of the
Peters Reserve. Depending on the wind direction, it is possible that the only egress route for
evacuating residents would be blocked by potentially dangerous vapour concentrations.
Based on the overland models (Section 7) and the vapour plume models (Section 1.3), it is
critically important that TMEP provide details of the Plan to provide evacuation options to the
members of the two Reserves, especially given the potential that responders may not be able
to enter the affected area. The Plan should answer the questions:
How will band members know if the egress routes are safe?
How will band members be notified (and by whom)
What vapour monitoring equipment and training will band members have?
Who will make the decision to shelter‐in‐place versus evacuation?
What about band members with disabilities, existing health problems?
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3 GroundwaterImpacts
Residents of both First Nations rely on the groundwater for drinking water, irrigation, and the
cattle farming (Peters).
The proximity of the proposed pipeline makes it next‐to‐impossible for a response to stop
spreading crude oil before it reaches either the Shxw'owhámel or Peters Reserves, (based on
the overland model and the TMEP’s proposed response times). As a result, ground water
contamination is highly likely.
Although benzene is naturally occurring at low concentrations, its presence in the environment
is mostly related to human activities. Gasoline contains low concentrations of benzene (below
1%), and emissions from vehicles are the main source of benzene in the environment. Benzene
can be introduced into water by industrial effluents and atmospheric pollution.
Health Canada has reviewed and assessed all identified health risks associated with benzene in
drinking water, incorporating multiple routes of exposure to benzene from drinking water,
including ingestion and both inhalation and skin absorption from showering and bathing. Health
Canada, in assessing newly available studies and approaches, taking into consideration the
availability of appropriate treatment technology, has established a guideline for benzene in
drinking water at a maximum acceptable concentration (MAC) of 0.005 mg/L (5 μg/L).
The guideline for benzene is established based on cancer end‐points and is considered
protective for all health effects. Benzene is classified as a human carcinogen. Both animal and
human studies report similar toxic effects from exposure to benzene. The most sensitive effects
are found in the blood‐forming organs, including the bone marrow.
The MAC for benzene in drinking water is established based on the incidence of bone marrow
effects and malignant lymphoma in mice, through the calculation of a lifetime unit risk.
For most Canadians, the major source of exposure to benzene is air; this accounts for an
estimated 98–99% of total benzene intake for Canadian non‐smokers. Like food, drinking water
is considered to be only a minor source of exposure to benzene. Benzene can be found in both
surface water and groundwater sources, but it is not generally a concern in surface water,
because benzene tends to evaporate into the atmosphere.
In the event that a crude oil spill affects the groundwater of either First Nation, it is critically
important to know what steps TMEP will take to ensure the mitigation of ground water
impacts, the temporary replacement of safe, reliable water, and the restoration of affected
groundwater.
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4 ICSTrainingforFirstNationsPersonnel
TMEP, in its submission, indicates that, in the event of an incident, TMEP would enter into a
Unified Command which would include affected First Nations.
Volume 7 Part 12 – Oil Spill Study ‐ TMEP was an early adopter of the ICS to manage
emergency response, with introduction of the system in the early 1990s. The ICS
structure outlines clear roles and responsibilities with respect to emergency response
and includes a unified command structure for co‐ordination with the multiple levels of
government; federal, provincial, municipal, and Aboriginal communities, along the
pipeline.
Currently neither the Shxw'owhámel or Peters First Nations personnel have any ICS training
and, as a result, would find it difficult to engage in a Unified Command under ICS. If TMEP
intends to engage First Nations representatives in a Unified Command, it is important to know
if TMEP plans to provide any ICS training to First Nations representatives, and if they will be
asked to attend, and become involved in exercises.
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5 OilSpillResponseEquipment
5.1 LimitationsofOilSpillResponseEquipment
The oil spill response equipment described in the TMEP documents is well‐suited to a relatively
narrow range of real‐life conditions. The oil containment booms described by TMEP (either in
their own Oil Spill Containment and Recovery (OSCAR) trailers, or owned by Western Canada
Marine Response Corp (WCMRC)) work well when containing floating oil in relatively slow (less
than 1 knot) currents, and their ability to deflect floating oil away from sensitive areas
deteriorates quickly in currents exceeding 3 knots. The portable oil skimmers (those that would
be used on spills in rivers) described by TMEP (either in their own OSCAR trailers, or owned by
WCMRC) are designed to work in relatively calm conditions (not in short‐period waves or
turbulence) or in winds exceeding 20 knots. Also, these portable oil skimmers are specifically
designed to recover floating oil, or oil in the top 10‐20 cm of the water column.
During the Deepwater Horizon spill response, the United States Coast Guard (USCG) reports
(see Figure 5.1) that of the approximately 5,000,000 barrels released from the MC 252 well,
around 800,000 barrels (16%) were collected from the devices fitted over the well. If that oil is
taken out of consideration (it is unavailable for recovery), then recovery of oil in open water
using skimmers accounted for around 3% of the oil.
Figure 5.1 – MC252 Oil Deposition (USCG)
The containment and recovery of oil in rivers is often made even more complicated by currents,
limited access, debris, ice, snags safety concerns, and various other issues. Conditions in the
Fraser River would render the use of conventional oil response techniques essentially
impossible during much of the year.
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8 Submerged/SinkingOils
The TMEP materials include a discussion of the fate (sometimes called weathering) of spilled
crude oil. However, there is a limited discussion on the mechanisms of sinking and/or
submergence.
The following discussion includes:
Predicting the Submerging and Sinking of Oil
Oil Submergence or “Over‐Washing”
Oil Density
A case study of the Line 6b (Enbridge spill) in Marshall, MI
Finally, since there are numerous references throughout the TMEP submission(s) to the
“Gainford Study”, conducted in 2013 In Gainford, Alberta, there is a discussion of the Study and
its applicability to this project.
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8.1 PredictingtheSubmergingandSinkingofOil
As is the case for all oil spills, every incident of submerged oil is a unique set of conditions based
on the type of oil, the environment in which it’s spilled, and other physical processes (Michel,
2008). Sunken oil is spilled oil which has negative buoyancy and will sink to the sea/riverbed.
Submerged oil is spilled oil that has near‐neutral buoyancy and has been submerged below the
surface (Rymell, 2009). Several main processes have been identified which could cause oil to
sink or become submerged.
Where the oil has an inherent density greater than the water in which it’s spilled, the oil will
sink to the sea/riverbed. Should the oil then move to an area with higher water densities, it
may rise again (Rymell, 2009).
Where the oil has a density close to the water in which its spilled, wave action and currents can
cause it to become submerged for periods and even trapped in the water column. This
emulsification and weathering can also cause lighter oils to increase in density and become
closer to that of the water. SL Ross conducted tank tests to develop a model for when oil may
submerge. It was determined that the oil must be viscous enough to break into fragments
small enough to become over washed. There must also be sufficient wave energy to push these
fragments below the water’s surface (Rymell, 2009).
Where floating oil is spilled or enters into an area with high concentrations of suspended
sediment, it can mix with the sediment increasing its density causing it to sink or become
submerged. Experiments in 1987 for the Integration of Suspended Particulate Matter and Oil
Transportation Study by Payne et al provide a “rule of thumb” regarding suspended sediment
concentrations leading to sinking oil (Rymell, 2009).
When stranded oil on a beach remobilizes, it can pick up sediment causing it to sink close to the
shore. This process requires that the oil have a suitably‐high viscosity and a shoreline substrate
consisting of sand or other coarse material. A short time period is also necessary for the oil to
incorporate the sediment. A rule of thumb is proposed that if the oil has a viscosity greater
than 20,000 cP and on a sand or shingle beach, it will have a high probability of sinking upon
remobilization (Rymell, 2009).
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Figure 8.1 ‐ General approach to modeling oil sinking or submerging. Photo from, RP595 Sunken and Submerged
Oils, 2009.
In the riverine waters near the Shxw'owhámel and Peters Reserves, the density and subsequent
movement of viscous oils will be affected by multiple factors, including emulsification,
sedimentation, tidal and other currents, waves generated by wind, low temperatures and
salinity anomalies. It is therefore likely that some percentage (10‐20%) of the bitumen‐blends
could sink within 10 days, or could be over washed easily by wave action in the turbulent
waters (Counterspil, 2011).
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8.2 OilSubmergenceor“Over‐Washing”
Large masses of oil that have a density close to that of water may be submerged for periods
from surface turbulence. This phenomenon is called over‐washing. Investigation has
discovered that oil will become over‐washed with densities as low as 0.90 g/ml, and over
washing time increases with oil density and wave size (Rymell, 2009).
Lab testing has shown that high‐viscosity, high‐density oils do not spread as a coherent slick but
rather formed “rafts” or “blobs” under the effect of waves. These blobs can be pushed rather
deep into the water and take a long time to resurface. Studies also revealed that in moderate
sea states, emulsified oil could be almost permanently covered in a layer of water (Rymell,
2009).
In a more recent analysis, it was found that the buoyancy behaviour of dilbits in marine
conditions depends most‐strongly on the presence of medium‐to‐fine sediment in the water
column. Evaporative weathering alone and evaporative and photo‐oxidation weathering in
combination all resulted in products that were buoyant in marine conditions. Mixing with
water generally increased the density of the products, but all oils tested remained buoyant in
seawater even when saturated with water. When mixed with fine‐ and moderate‐sized
sediments however, the fresh‐ to moderately‐weathered dilbits sank in saltwater…..this work
demonstrates that, in waters where fine‐ to moderate‐sized sediment is present, these oils are
at risk to sink, when there is a high degree of mixing energy available (Environment Canada,
2014).
During many parts of the year, the Fraser River delta has been found to have sediment
concentrations approaching 1 g/L during the highest annual flows (Kostaschuk et al., 1993),
thus creating an environment in which, when combined with sufficient mixing energy
(turbulence), could certainly sink.
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8.3 OilDensity
If the density of oil is greater than the water in which it’s spilled, it will sink. The American
petroleum institute’s “API gravity” is the standard measure of “heaviness” or density of oils
when compared to water.
When coupled with viscosity, it creates four categories for crude oil (Rymell, 2009).
1. Light Oil: is also known as “conventional oil”, with an API gravity of at least 22° and a
viscosity less than 100 cP.
2. Heavy Oil: described as above, the upper API gravity limit being set at 22° and a viscosity
of less than 100 cP.
3. Extra‐Heavy Oil: like Heavy Oil but with an API gravity of less than 10°.
4. Natural Bitumen: also known as “oil sands”, is like Heavy Oil but even more dense and
viscous with a viscosity greater than say 10,000 cP.
Freshwater has a density of 1.000 g/ml, and seawater typically has a density of 1.025 g/ml. The
salinity and density of water are proportional (Rymell, 2009).
*Density vs. Sinking behavior of oil, from RP595 Sunken and Submerged Oils, 2009.
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Few oils have densities greater than full‐salinity seawater. These are highly‐cracked oils are
also known as slurry oils or black carbon. Depending on the speed of current, the sinking oil
may be sheared into small droplets and spread over a vast area, or pool in depressions in the
seabed (Rymell, 2009).
If the density of the oil is close to but less than the water into which it’s spilled, it will initially
float, but sit very low in the water. Low‐viscosity oils will be naturally dispersed by wave action,
but if the viscosity is high, the oil will be broken into blobs of spilled oil (Rymell, 2009).
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8.4 CaseStudy–EnbridgeLine6bRelease,Marshall,MI
On July 26, 2010, 20,084 US Barrels (bbls) of crude oil released near Marshall, Michigan from
Enbridge’s Line 6b near Marshall, MI. The crude (reported by Enbridge) released was a
combination of (77.5%) Cold Lake a heavy dilbit, and (22.5%) MacKay River Heavy, a heavy
synbit (USEPA, May, 2013).
Of the 20,080 bbls (843,360 gallons) of crude released from the pipeline, it is estimated that
only 8,333 bbls (350,000 US gallons) reached Talmadge Creek, and eventually the Kalamazoo
River. The river was in a flood condition at time of release (USEPA, May, 2013).
It is unclear at which point it was realized that some percentage of the oil had submerged/sunk,
however it would soon become clear that a considerable amount of oil was on the bottom, in
the sediments of the creek and river.
It would eventually be determined by EPA officials that primary mechanisms of submergence
were (USEPA, May, 2013):
– volatilization of light ends
– Emulsification, and
– interactions and agglomeration onto sediment (dominant)
The EPA (USEPA, May, 2013) would later estimate that, as of July/August 2012 (2 years after the
spill, and much of the cleanup) that:
The total submerged Line 6B oil volume for the discharge site is estimated to have been 180,000 gallons ± 100,000 gallons when summed over all sampling strata.
In summary, the calculated estimate of submerged Line 6B oil quantified in sediment supports other assessment and monitoring results. These multiple lines of evidence indicate that submerged Line 6B oil is present and has migrated into depositional areas along the entire 38-mile-long reach of the Kalamazoo River affected by the July 2010 Line 6B oil discharge.
Since the spill occurred in July, in relatively warm temperatures, it can be conservatively
estimated that 10% (35,000 gallons) of the crude entering the creek would have evaporated,
thus only around 315,000 gallons remained, at least for a while, on the water surface.
Based on the EPA’s numbers, the range of percentages of the oil that entered the creek that
would ultimately sink or submerge would be from 25% (at the low end of the EPA’s estimate) to
89% (at the high end). Based on the EPA’s best estimate, some 57% of the oil that entered
Talmadge Creek would ultimately find its way to the sediments on the bottom.
EmergWest Consulting Trans Mountain Expansion Project
Draft Report 74 March 2015
8.5 GainfordStudy
8.5.1 General
In June 2012, Trans Mountain Pipeline ULC (TMPL) asked O’Brien’s Response Management to
organize a study on diluted bitumen (dilbit) products to support their application for the TMEP.
The stated purpose of the study was to further the knowledge of dilbit in general and, more
specifically, to investigate the behavior of dilbit when spilled into a marine environment.
Unfortunately, the Gainford Study was extremely limited in scope, in that only two crude oils
were tested, and an environment was chosen in which it was highly unlikely that any of the oil
would sink. The tests were conducted only using a salt water environment. Also, oil
thicknesses and wind apparatus were used that were unlikely to create small oil droplet
formation. Also, no suspended sediments, clays, or plant matter were present, which would
have increased the likelihood of the oil sinking. Finally, the study was limited in time to stop at
a point in time when the oils might have sunk.
The Study was also not designed to test current capability of recovering sunken/submerged oil:
Page vii “Is the performance of the equipment currently stockpiled by North American oil
spill recovery organizations adequate to mechanically remove diluted bitumens off the
surface of the water?”
Unfortunately, as a result of these limitations, the results of the study cannot be reasonably
used to represent many of the conditions in which crude oil could be spilled. It is even more
unfortunate that the study designers, knowing that a considerable percentage of the crude oil
spilled in the Enbridge (Marshall) incident did sink, did not design the study to determine at
which point the key variables, i.e., water density, sediment load, and turbulence, would cause
these crude oils to sink.
EmergWest Consulting Trans Mountain Expansion Project