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2017-336:Diluted bitumen (dilbit), an oil sands product, may present new response challenges differing from conventional crude oil in terms of its potential environmental impacts. Simple naphthenic acids (NAs), a complex group of monocarboxylic acids, with a general formula CnH2n+zO2, may be present in the source bitumen or may be created by photolytic weathering. Knowing the composition and concentrations of NAs created during the photo-degradation process of dilbit will help understand the fate, behavior and toxicity of dilbit.In the present study, two diluted bitumen products, Cold Lake Blend (CLB) and Access Western Blend (AWB), were mixed with saltwater and irradiated with natural solar light (Ottawa, Canada, 45.4°N) over winter and summer seasons, to assess the impact of sunlight on the chemical fate of the dilbit. For comparison, a light, sweet crude oil was exposed under similar conditions. The samples were analyzed by high performance liquid chromatography-high resolution mass spectrometry to examine the molecular transformation of diluted bitumen by solar irradiation. The abundances of NAs in all three test oils increased significantly after 90 days of solar irradiation, strongly suggesting that polar NAs were formed by photolysis. Further, greater increases in NAs in the light crude were found than in the two dilbits. Similarly, the lighter oil had higher photolytic removal rates of petroleum hydrocarbons than the two dilbits.The concentrations of NAs in oils exposed during the summer were generally higher than those exposed in winter. During summer exposure, the abundance of total NAs increased up to the 30-day’s solar exposure, then fell again, indicating the transient nature of these compounds. However, net increases in polar NA compounds were observed for all the winter exposed samples. Greater increases were observed in the smaller NA compounds (average C-number decreased), also accompanied by an increase in saturation (average z-number decreased).These chemical changes strongly indicate the effect of sunlight on the potential behaviour, fate and effects of spilled oil, with creation of new resin group compounds and reduction of aromatics and saturates. These changes may affect the viscosity of the oil and its ability to uptake water. These chemical compositions also imply significant changes to the ecological effects of the oil following a spill when aged in sunlight.

2017-217 One of the major unknowns with respect to the fate and behavior of spilled dilbit is its state of buoyancy, particularly when mixed with sediments. What form do diluted bitumen and sediment mixtures take, and will they float or sink in water column? In this study, we evaluated the fate and behavior of Cold Lake Blend-Winter at three different weathering states (i.e., fresh, medium, and heavily weathered) in high-energy mixing marine conditions, with (and without) sufficient concentrations of sediments to ensure formation of oil-particulate aggregates (OPA). Conventional light crude oil and intermediate and heavy fuel oils were also included to serve as references for behavior of other types of oils. Two mineral sediments including kaolin (fine) and sand (coarse) as well as natural sediment from the Douglas Channel (DC) in northern British Columbia, (medium) were used for this evaluation. The resulting OPAs were characterized in terms of buoyancy, OPA density, particle size distribution, and morphology to better understand the oil-sediment interaction. In the absence of sediment, mixing of the oils with water resulted in meso/entrained–water-in-oil mixtures; these mixtures remained floating on the water surface. However, in presence of kaolin or the DC sediments, a significant portion of the OPA sank to the bottom of the water column for all oils, with the exception of the light crude oil and the highly weathered Cold Lake Blend-Winter. The later did not uptake as much sediment and instead formed discrete free-floating tarballs. In experiments with the larger sand sediment, no OPAs formed. The density and particle size analysis revealed that the OPAs of the oils with higher viscosity tended to have larger densities and particle sizes. Microscopic examination of the OPAs showed that all consisted of oil droplets surrounded by sediment particles and were present in single droplet or multiple-droplet clusters.

2017-182 The dispersal and weathering processes of crude and fuel oils have been studied for decades and significant scientific information has been published. However, the fate and behaviour of spilled nonconventional crude oil such as diluted bitumen products are less well understood. There is concern that a spill of the oil sands diluted bitumen may come into contact with marine shorelines as it is transported throughout Canada. There is uncertainty related to the fate of spilled diluted bitumen and potential interactions with shorelines. A Shoreline Oil Spill Research and Development Program was undertaken by Environment and Climate Change Canada (ECCC). In 2013, a 3-year study was initiated and focused on the marine shorelines of northern British Columbia (BC). Four field campaigns were conducted along the entire length of coast throughout the Douglas and Granville channels as well as Banks and Haida Gwaii islands. The field campaigns were used as an opportunity to develop and employ a new approach to collect and compile an extensive pre-spill baseline dataset. Data included an aerial survey with high definition video and a ground survey of representative shorelines where samples were collected and analyzed for petroleum hydrocarbons, carboxylic acid, pesticides, heavy metals, calcium carbonate and sediment grain size. Baseline levels of hydrocarbons in the sediment of the study areas were estimated based on the analysis of total petroleum hydrocarbons (TPH), n-alkanes ranging from n-C9 to n-C40, petroleum related biomarkers such as terpanes and steranes, polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues (APAHs).

As it is well established that application of chemical dispersant to oil slicks enhances the concentration of oil droplets and reduces their size, chemical dispersants are expected to enhance oil sedimentation if applied in coastal waters rich in suspended particulate matter (SPM) and if flocculation between chemically dispersed oil and SPM, which leads to formation of oil-SPM aggregates (OSAs), occurs readily. New laboratory experiments were conducted to establish a quantitative understanding of the process and to verify this hypothesis. This paper presents findings from experiments conducted using Standard Reference Material 1941b prepared by the National Institute of Standards and Technology, Arabian Medium, Alaska North Slope and South Louisiana crude oils, and Corexit 9500 and Corexit 9527 chemical dispersants. Results showed that OSAs do form with chemically dispersed oil. Oil sedimentation increases with sediment concentration and reach a maximum at a sediment-to-oil ratio of approximately 2:1 for most of the oils used. No obvious effect of chemical dispersant on oil sedimentation was measured for sediment concentration of 100 mg/L and higher. However, measured oil sedimentation was 3 to 5 times higher with chemical dispersant than with physically dispersed oil at low sediment concentration of 25 and 50 mg/L. UV epi-fluorescence microscopy showed that OSAs formed with chemically dispersed oil contain many oil droplets that are smaller than those trapped in OSAs formed with physically dispersed oil.

In this work, 14 fresh crude oils of different types and origins were analyzed by gas chromatography with mass-selective detection, and over 80 potentially diagnostic ratios were calculated based on the quantitation of isoprenoids, polycyclic aromatic hydrocarbons (PAHs), biomarkers, diamondoids, bicyclic sesquiterpanes and aromatic steranes, etc. Diagnostic power (DP) was calculated for the selection of the candidate source-sensitive diagnostic ratios and used to determine which ratios were most diagnostic among the crude oils studied. In order to investigate the effect of evaporative and biodegradative weathering on diagnostic ratios and thereby to differentiate weathering-resistant ratios from weathering-sensitive ratios, triplicate analyses were performed for two suites of reference oils, laboratory-evaporated Prudhoe Bay crude oils and laboratory-biodegraded Alberta Sweet Mixed Blend (ASMB) crude oils, respectively. Student'S t-test was used to statistically evaluate whether diagnostic ratios were significantly affected by weathering and to ensure that the observed change is not due to analytical variance. It was found that, diagnostic ratios generally remained consistent for oils with slight to medium evaporative weathering, only the ratios of those compounds with lower boiling points such as adamantanes changed greatly. For biodegraded oils, most of diagnostic ratios remained constant for lightly to moderately biodegraded oils; while most of diagnostic ratios with exception of certain triaromatic steranes and high-molecular-weight terpane and sterane biomarkers demonstrated significant changes for heavily biodegraded oils.

Examination of GC-MS chromatograms of bicyclic biomarker sesquiterpanes and diamondoids using their characteristic fragment ions provides another highly diagnostic means for correlation and differentiation of unknown spilled oil samples that are difficult to identify by current fingerprinting techniques. In this work, GC-FID and GC-MS fingerprinting analysis in conjunction with statistical data analysis of target oil hydrocarbons including sesquiterpanes and diamondoids was performed for identification of an unknown oil spill incident occurred in a harbor of the Netherlands in 2004. Forensic investigation included the: (1) identification and characterization of numerous sesquiterpanes and diamondoids; (2) comparison of the distribution of sesquiterpanes and diamondoids; (3) development of a series of diagnostic indices for correlation and differentiation of spilled fuel samples; and (4) use of “Two-tailed” unpaired Student'S t-test to statistically evaluate the imperceptible differences between the selected diagnostic ratios of target compounds in the spill fuel and the suspected source fuel samples. At a 95% confidence interval, 33 of all 38 diagnostic indices (among them, 20 are diagnostic indices of sesquiterpanes and diamondoids) show positive matches between spill sample and suspected source fuel sample 1. In comparison, only 5 of 38 diagnostic indices indicate positive matches between spill sample and suspected source sample 3. These evidences demonstrate that the bunker ship has the responsibility for this oil spill incident.

A new diagnostic parameter of “Pyrogenic Index (PI),” defined as(other 3–6 ring EPA priority PAHs)/N(5 alkylated PAHs), has been proposed as a quantitative indicator for identification of pyrogenic PAHs and for differentiating pyrogenic from petrogenic PAHs. It has been well understood that petrogenic and pyrogenic PAHs are characterized by dominance of five alkylated PAH homologues and by dominance of unsubstituted high molecular weight PAHs, respectively. In comparison with traditional diagnostic ratios such as phenanthrene/anthracene (Ph/An), benz[a]anthracene/chrysene (BaA/Ch), and fluoranthene/pyrene (Fl/Py), the PI Index more truly reflects the difference in the PAH distribution between these two sets of PAHs. The PI Index has been successfully used as an effective criterion to unambiguously differentiate pyrogenic and petrogenic PAHs. In this paper a case study is presented to illustrate the utility of the PI index to distinguish the pyrogenic PAHs generated by burning from the petrogenic PAHs. On October of 2004, a fire accident happened in the HMCE Chicoutimi submarine at sea off the west coast of Ireland as the submarine was making its way to Halifax, Canada. In order to determine effects of the fire accident on the health of crew members, a number of fire samples were collected and sent to the ESTD for characterization. Sample characterization results clearly revealed that the distribution profiles of PAHs in the samples are combined signatures from both pyrogenic and petrogenic PAHs. The pyrogenic PAHs were generated from the fire accident, while the petrogenic PAHs came from contamination of petroleum products used by the submarine. The presence of petroleum hydrocarbons is further confirmed by the discovery of oil-characteristic n-alkanes and biomarker compounds in the fire samples.

Several oil spill remote sensing flights were conducted by Environment Canada off the Southern coast of Newfoundland, Canada in late February, early March 2004. These flights were undertaken to demonstrate the capabilities of the Scanning Laser Environmental Airborne Fluorosensor (SLEAF) in real-life situations in the North Atlantic and Newfoundland coastal regions in late winter weather conditions. Geo-referenced infrared, ultraviolet, color video and digital still imagery was collected along with the laser fluorosensor data. Brief testing of a Generation III night vision camera was also conducted. Flights were conducted in the shipping lanes around the Newfoundland coast, out to the Hibernia and Terra Nova oil platforms and over known oil seep areas. Details of the analysis of laser fluorescence data collected during these flights will be presented along with a summary of the remote sensing flights.

Bituminous fuels (in the form of water-based emulsions) are increasingly being used as fuel sources in many countries. When spilled in a marine environment, these emulsified fuels initially disperse and then, under certain circumstances, coalesce to become highly adhesive to beaches and shorelines. These fuels may either float or submerge, depending on the salinity of the water into which the spill occurs. Similar situations are known to occur with some conventional heavy fuels, as was the case with the Erika incident off the coast of France. Technologies to detect these neutrally buoyant and/or submerged fuels are urgently needed. The remote detection of submerged oil is a daunting task. The majority of sensors commonly used for the detection of surface oil slicks are of no use for the detection of submerged oil. Environment Canada and the Canadian Coast Guard have recently undertaken a series of bench-scale studies to develop technologies for the real-time remote detection of neutrally buoyant and/or submerged fuels in the marine environment. The unique capabilities of “active sensors” such as laser fluorosensors are being evaluated for the subsurface detection of heavy petroleum products. The detection of submerged Orimulsion by laser-induced fluorescence has been demonstrated at a distance of 81 m (265 feet) in a small test tank. Further experiments are underway to confirm the real-time detection of submerged Orimulsion, initially on the ground, and then through airborne tests.

In the next few years, several new satellite sensors will be launched by various national remote-sensing/earth observation agencies around the globe. It is hoped that these space-borne sensors will provide oil spill response personnel with more than just a synoptic overview of the spill scene. The state-of-the-art capabilities of these new sensors should provide responders with information that can be used in a tactical role as opposed to older-generation sensors that perform a strictly strategic role. Of primary use to spill response coordinators is the Synthetic Aperture Radar (SAR) sensor. The next generation of SAR satellites will have enhanced capabilities when compared to their predecessors. The enhancements include the addition of Polarimetric modes for satellites, including Envisat-1 and RADARSAT-2. RADARSAT-2 will be quad-polarimetric, with resolutions of 8 × 8 m in Polarimetric mode and down to 3 × 3 m in co- or cross-pole modes. The ASAR sensor on Envisat-1 will follow up the successful missions of the European Space Agencies ERS-1, −2 satellites. ASAR will have an alternating polarization mode, and transmit and receive polarization can be selected, thus allowing scenes to be imaged simultaneously in two polarizations. In addition to SAR satellites, several new optical satellites have been or will be launched over the next few years. While optical sensors often are plagued by periods of foul weather that frequently accompany oil spills, some of these sensors will provide valuable information that can be used in conjunction with the radar data in a corroborative fashion. The most useful of the new optical satellites might well be those used to collect data for weather forecasting. This paper will review the operating characteristics and modes of recent and planned satellite sensors, with an eye toward their usefulness for tactical remote sensing of oil spills.

It is now possible to measure the thickness of an oil slick on water by remote sensing. A laboratory sensor has been developed to provide this absolute oil slick thickness measurement. A joint project between Environment Canada, U.S. Minerals Management Service (MMS), Imperial Oil Research Ltd., and Industrial Materials Institute of the National Research Council of Canada has led to the development of a prototype slick thickness measurement system, known as the Laser Ultrasonic Remote Sensing of Oil Thickness (LURSOT) sensor. This prototype was the first step in achieving the ultimate goal of providing an airborne sensor for the remote measurement of oil slick thickness on water. The LURSOT sensor employs three lasers to produce and measure the time-of-flight of ultrasonic waves in oil, hence providing a direct measurement of oil slick thickness. The successful application of this technology to the measurement of oil slick thickness will benefit (1) the scientific community as a whole by providing information about the dynamics of oil slick spreading and (2) the spill responder by providing a measurement of the effectiveness of spill countermeasures such as dispersant application. The first part of this paper provides initial results from laboratory testing prior to a second round of airborne test flights of the modified LURSOT system. The second part of this paper provides details on a new generation of laser fluorosensor, known as Scanning Laser Environmental Airborne Fluorosensor (SLEAF). SLEAF recently has been installed on Environment Canada's DCS aircraft. SLEAF incorporates a high-power excimer laser, high-resolution range-gated intensified diode-array spectrometer, and a pair of variable speed and angular displacement scanning mirrors. These scanning mirrors provide SLEAF with the across-track sampling pattern needed to detect narrow bands of oil that can pile up along the high tide lines of beaches and shorelines. Ground testing of SLEAF has now been underway for some time. This paper provides details of the sensor installation and testing program, and illustrates the operational capabilities of the new system. It is believed that this new sensor will provide prompt reliable detection and mapping of oil contamination in a variety of marine and terrestrial environments.

The intended role of the scanning laser environmental airborne fluorosensor (SLEAF) is to detect and map oil and related petroleum products in complex marine and shoreline environments. To improve on the small footprint and nadir-looking geometry of the previous generation laser fluorosensor, the LEAF, a conical scanning mirror was included to provide the broad cross-track and along-track sampling required to detect oil in these complex environments. Laser fluorosensors have the ability to confirm or reject suspected oil contamination sites that have been targeted by other “nonspecific sensors” such as infrared, ultraviolet or visible cameras. This confirmation will free response crews from the labourious task of physically inspecting each site, and direct crews to sites that require immediate remediation. The construction of the SLEAF system was recently completed. Following integration of the various components of the system, a systematic verification of SLEAF system functionality was initiated. The ability of the SLEAF to detect, classify, and estimate oil coverage was tested and verified. In total, 21 oils ranging from light refined, crude through to heavy refined oils were examined. The API gravities of the oils examined varied from 11.9 to 48.6, while the aromatic content varied between 13 and 52%. The SLEAF system is presently being integrated into Environment Canada's DC-3 aircraft and will undergo extensive testing to confirm its functionality in an airborne environment. This paper will report on progress with the installation of the SLEAF system.

When oil is spilled into the marine environment, it may be found on the water's surface, in the water column, in the sediment, or on the shoreline. When delineating the extent of contamination, it is important to be able to differentiate the spilled oil from other components that may appear to be oil. There are established methods for detecting oil-in-water, such as fluorometry, that allow in situ measurements to be made. In this study, we investigate both established methods and potential technological advancements that could provide a means for a site investigator to gather meaningful on-site information regarding the presence of oil. The primary focus will be usefulness to a shoreline application, but application to other types of samples is addressed. The degree to which an oil could be identified using these portable methods, such as the ability to differentiate petrogenic from biogenic oils, is also discussed. Method comparisons are discussed, with relevance to portability, selectivity, relative cost, and ability to process multiple samples.

On August 3, 2005, a Canadian National Railway train derailed within the Whitewood Sands community of the Wabamun Lake area. The derailment resulted in the release of 712,500 liters of Bunker C oil and 88,000 liters of pole treating oil from the rail cars into the adjacent Wabamun Lake water. To estimate the hydrocarbon-degrading capabilities of microbes naturally present in oil-contaminated Lake Wabamun sediment, laboratory tests were conducted at the University of Alberta under two incubation conditions. The tests incubated spilled Bunker C oil recovered from the lake and the reference oil, Alberta Sweet Mix Blend (ASMB), at 22°C for 4 weeks or at 4°C for 8 weeks. Residual oil was recovered and quantitatively characterized at the Oil Research Laboratory of Emergencies Science and Technology Section, Environment Canada. Biodegradation results demonstrated that Lake Wabamun sediment microbes were capable of degrading a significant proportion of the ASMB reference oil at both incubation temperatur...

Detecting oil in the marine environment with remote sensing is difficult at the best of times. When that environment includes ice, kelp or seaweed, and the myriad substrates found on beaches and shorelines, the detection becomes increasingly difficult. The laser fluorosensor is the only sensor that detects a primary characteristic of petroleum products, namely, their unique fluorescence spectral signatures. A laser fluorosensor reliably detects oil on ice in ice-infested waters, among floating kelp and seaweed beds, and on complex beach and land environments. This paper will provide details of the Scanning Laser Environmental Airborne Fluorosensor (SLEAF) and the anticipated benefits of the SLEAF system to the oil spill response community.