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The characterization of spilled petroleum products in an oil spill is necessary for identifying the spill source, selection of clean-up strategies, and evaluating potential environmental and ecological impacts. Existing standard methods for the chemical characterization of spilled oils are time-consuming due to the lengthy sample preparation for analysis. The main objective of this study is the development of a rapid screening method for the fingerprinting of spilled petroleum products using excitation/emission matrix (EEM) fluorescence spectroscopy, thereby delivering a preliminary evaluation of the petroleum products within hours after a spill. In addition, the developed model can be used for monitoring the changes of aromatic compositions of known spilled oils over time. This study involves establishing a fingerprinting model based on the composition of polycyclic and heterocyclic aromatic hydrocarbons (PAH and HAHs, respectively) of 130 petroleum products at different states of evaporative weathering. The screening model was developed using parallel factor analysis (PARAFAC) of a large EEM dataset. The significant fluorescing components for each sample class were determined. After which, through principal component analysis (PCA), the variation of scores of their modeled factors was discriminated based on the different classes of petroleum products. This model was then validated using gas chromatography-mass spectrometry (GC-MS) analysis. The rapid fingerprinting and the identification of unknown and new spilled oils occurs through matching the spilled product with the products of the developed model. Finally, it was shown that HAH compounds in asphaltene and resins contribute to ≥4-ring PAHs compounds in petroleum products.

The ability to characterize the composition of emerging unconventional Bakken tight oil is essential to better prepare for potential spills and to assess associated environmental concerns. The present work measured and compared the physical and chemical properties of Bakken crudes with conventional crude oils from various regions and different types of refined petroleum products. The physicochemical properties of Bakken crude are overall similar to those of conventional light crudes. The Bakken crude consists of high concentrations of monoaromatic hydrocarbons and alkylated PAHs with a clear dominance of the alkylated naphthalene homologues followed by the phenanthrene series. Its pyrogenic index (PI) values are considerably lower than typical conventional crude oils. The Bakken crude oils in this study exhibit a low abundance of petroleum biomarker such as terpanes, steranes and diamondoids and bicyclic sesquiterpanes. Since tight oil from the Bakken region is produced from low-permeability formations, variations in abundance and diagnostic ratios of common target petroleum hydrocarbons were found among these oils.

Polycyclic aromatic sulfur heterocycles (PASHs), as a group of major sulfur-containing compounds, widely occur in crude oil and its refined products. Accurate analyses of these petrochemical components play an important role in monitoring oil quality, forensic source identification, and assessment of environmental impact of an oil spill. PASHs occur at relatively lower abundances in most crude oils and refined petroleum products than their corresponding aromatic hydrocarbons and are co-eluted together with some petroleum hydrocarbons in chromatographic analysis, resulting in high uncertainty for their quantitation. Capillary gas chromatography coupled with a quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) provides high resolution and high mass accuracy, which facilitates discrimination of the delicate mass defects of isobaric compounds with the same nominal mass and external matrix material. In this work, GC-QTOF-MS was applied to analyze bicyclic to pentacyclic PASHs including benzothiophenes, dibenzothiophenes, benzonaphthothiophenes, dinaphthothiophenes and their C1- to C4- alkylated homologues in a number of crude oils, refined petroleum products, and environmental samples. GC-QTOF-MS analysis substantially improved the identification confidence and reduced quantitation uncertainty of PASHs and polycyclic aromatic hydrocarbons (PAHs) by eliminating the interferences presented in nominal mass chromatograms.

Total petroleum hydrocarbons (TPH), n-alkanes, petroleum-related biomarkers of terpanes and steranes, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the intertidal sediments in the Bay of Fundy, Nova Scotia/New Brunswick, Canada. Sites close to the harbour and more densely populated areas had higher TPH levels than other pristine areas. n-Alkanes presented a typical single bell-shape in n-C16 to n-C35 range and an obvious odd to even carbon preference. Most sites had trace amounts of petroleum biomarkers. Abundant non-alkylated PAHs and lower amounts of alkylated PAHs represented the major input of the incomplete combustion of solid (e.g., coal, coke, biomass, and coal tar) and liquid fuels. The toxicity estimation for PAHs indicates that they did not have potential toxicity to benthic organisms at most sampling sites. However, possible to probable negative effects from the measured PAH concentrations were found for the two samples from Courtenay Bay and Saint Andrews.

A large amount of polycyclic aromatic hydrocarbons (PAHs) and their heterocyclic analogues (N, S, O) are released to the marine environment from natural oil seeps, oil spills, bilge discharges and input of land-based sources. Many of these compounds are toxic and have a deleterious effect on marine biota. Nitrogen-containing compounds in crude oils are typically present as cyclic compounds such as polycyclic aromatic nitrogen heterocycles (PANHs) and are generally classified into the two categories of nonbasic (N-PANHs) and basic compounds (B-PANHs). Chromatographic analyses of PANHs are easily to be interfered by other oil components without proper sample preparation prior to instrumental analysis. In this work, dual solid phase extraction columns of 3-(isocyanato)propyl-functionalized silica gel (Si-NCO) and silica gel were employed to efficiently separate both N-PANHs and B-PANHs from saturated and aromatic petroleum hydrocarbons, which enable simultaneous accurate analyses of these groups with single sample preparation. Crude oils studied contain various concentrations of N-PANHs including carbazole, benzocarbazole and B-PANHs including quinolone, acridine and benzoacridine as well as their alkylated homologues. These compounds in light fuel and lubricating oil are generally not detected or are only in trace concentration, but have considerable abundance in heavy fuel oils. Crude oils from different sources and various petroleum products have their unique absolute concentrations and relative distribution patterns of PANHs. Chemical fingerprints of PANHs can provide valuable information for forensic oil spill identification and improve the understanding of the fate, behaviour and chemical degradation of spilled crude oil.

The characterization, identification, and correlation of oils are comprehensive and challenging tasks due to the wide variability in petroleum products. Forensic oil fingerprinting analysis becomes even more complicated once oil is released into the environment and subjected to various weatherings. It is extremely important to collect reliable evidence for each specific case. The most important criteria from quantitative chromatographic analyses are concentrations, distribution profiles, and diagnostic ratios of source-specific petroleum compounds. The selection of diagnostic ratios should be based upon a particular spill case including the oil type, weathering condition, and the abundance and distribution of target compounds. Oil fingerprinting analysis has advanced greatly in recent decades due to the rapid development of analytical and statistical techniques. Although automatic analysis using computerized techniques and database inputs could be a trend in the future, defensible source identification still heavily relies on systematic analysis, meticulous examination, and scientific interpretation of all available information by experienced environmental forensic scientists. This chapter provides an overview of analytical methodologies for separation and analysis of selected petroleum hydrocarbons and detailed chromatographic and quantitative chemical fingerprints of various crudes and refined petroleum products. This chapter also discussed the weathering effect on the chemical properties of oils under evaporation, biodegradation, and photodegradation.

Polycyclic aromatic hydrocarbons (PAHs) are compounds of concern because most of these compounds are toxic, carcinogenic, or mutagenic and are relatively persistent in the environment. Reliable quantitative information of PAHs is important to evaluate the acute and chronic harmful effects of PAHs on the ecosystem. Crude oils and refined petroleum products contain many highly abundant PAHs and heterocyclic PAHs, in particular the alkylated homologues of naphthalene, phenanthrene, dibenzothiophene, fluorene and chrysene (APAH). The alkylated PAH homologues usually occur in significantly higher concentrations than their corresponding unsubstituted parent PAHs. Petrogenic alkylated PAHs generally consist of large numbers of isomers. Unlike those individual unsusbstituted PAHs, most of the APAH isomers are not commercially available. Therefore, historically, the target APAHs are generally quantified using the relative response factors (RRFs) obtained from their respective unsubstituted parent PAH compounds, this inevitably results in the quantitative results of APAH being significantly underestimated. In order to improve the accuracy of the measurement of PAHs and their alkylated homologues in oil and oil related samples, this study measured and compared the response factors of a large number of alkylated PAHs relative to the internal standards in gas chromatography-mass spectrometry (GC-MS) analysis, with the goal of developing a more accurate quantitative methodology for the determination of oil APAHs, and eventually leading to a standardized methodology of quantitative APAH analysis. The PAHs in different oils and related environmental samples collected from oil impacted areas were determined using this GC-MS methodology. Furthermore, the influence of the measurement methodology on the diagnostic ratios of target PAHs was also assessed in this work.

Remote-sensing for oil spills is reviewed. The use of visible techniques is ubiquitous, however it gives only the same results as visual monitoring. Oil has no particular spectral features that would allow for identification among the many possible background interferences. Cameras are only useful to provide documentation. In daytime oil absorbs light and remits this as thermal energy at temperatures 3-8K above ambient, this is detectable by infrared (IR) cameras. Laser fluorosensors are useful instruments because of their unique capability to identify oil on backgrounds that include water, soil, weeds, ice and snow. They are the only sensor that can positively discriminate oil on most backgrounds. Radar detects oil on water by the fact that oil will dampen water-surface capillary waves under low to moderate wave/wind conditions. Radar offers the only potential for large area searches, day/night and foul weather remote sensing.

Aromatic steroids including monoaromatic (MAS) and triaromatic steroids (TAS) are a series of naphthenoaromatic hydrocarbons, which consist of mixed structures of aromatic and saturated 6-carbon or 5-carbon rings. Although these aromatic steroids are in relatively low concentration in oils, their specific fingerprints and high weathering resistance make them desirable biomarkers for the characterization, correlation, differentiation, and source identification in environmental forensic investigations of oil spills. This study presents a quantitative GC/MS analysis of these aromatic hydrocarbons in a number of crude oils and refined petroleum products including light and mid-range distillate fuels, heavy fuels, and lubricating oils collected from various sources. TAS-cholestanes (C26), TAS-ergostanes (C27), and TAS-stigmastanes (C28) are the most distinguishable triaromatic steroids in most oil samples. C26 TAS-cholestane (20R) and C27 TAS-ergostane (20S) are coeluted and often present as the highest peak i...

The fingerprinting of oil spills can be a challenge to analytical chemists due to the complex nature of crude oils and the low concentrations of many constituents of interest. Oils spilled into the environment are immediately subject to various natural weathering processes, subsequently altering the chemical fingerprints and composition of spilled oils. In addition, background materials could severely interfere with the accurate determination of petroleum compounds when applying currently established analytical techniques, for example, single quadrupole GC–MS. Gas chromatography coupled with quadrupole time-of-flight mass spectrometer (GC–QTOF) greatly enhances the resolution of individual series of compounds and, owing to GC–QTOF’s accurate mass measurements, subsequently reduces interferences from the sample matrix and thereby provides more accurate identification and quantitation of targeted spilled oil components. This chapter provides an introduction and overview of the application of GC–QTOF in the chemical fingerprinting analysis of petroleum oils and petroleum-contaminated environmental samples.

Biological markers, or biomarkers, are one of the most important hydrocarbon groups in petroleum used for chemical fingerprinting. Biomarkers can be detected in low quantities (ppm and sub-ppm level) in the presence of a wide variety of other types of petroleum hydrocarbons by the use of the gas chromatography–mass spectrometry (GC–MS). Relative to other hydrocarbon groups such as alkanes and most aromatic compounds, biomarkers are highly resistant to degradation in the environment. The chapter provides analytical methodologies for petroleum biomarker fingerprinting, which include: petroleum biomarker families and labeling and nomenclature of biomarkers. The benchtop quadrupole GC–MS systems, although lacking the high-resolution capabilities of larger and more expensive magnetic-sector instruments, have sufficient sensitivity and selectivity for most purposes of biomarker analysis. In addition to petroleum biomarkers, oil-contaminated sediment samples may contain modern plant biomarker compounds. Chemical fingerprinting of source characteristic and environmentally persistent biomarkers generates information of great importance to environmental forensic investigations in terms of determining the source of spilled oil, differentiating and correlating oils, and monitoring the degradation process and weathering state of oils under a wide variety of conditions.

Light petroleum biomarkers such as bicyclic sesquiterpanes and diamondoids are ubiquitous components of crude oils and ancient sediments, and are also widely found in intermediate petroleum distillates and many finished petroleum products. These compounds are relatively resistant to biodegradation and light-to-medium evaporation weathering, thus particularly useful in oil-source correlation and differentiation for those cases where the traditional tri- to pentacyclic biomarkers are absent. This work utilized sesquiterpanes and diamondoids for fingerprinting and identification of light oils spilled on water. The gas chromatography/flame ionization detection (GC/FID) analysis and distribution profiles of polycyclic aromatic hydrocarbon (PAHs) and conventional biomarkers suggest that the spilled oils are mixtures of mainly gasoline and light diesel type fuel. Since potential source oil candidates were not available, and a large part of the hydrocarbons in gasoline and diesel co-eluted in chromatographic anal...

JOURNAL OF CONTEMPORARY WATER RESEARCH & EDUCATION There are approximately 52,000 “community” water systems (Rourke and Selby 2002) and 16,000 “publicly owned treatment works” or wastewater systems (U.S. Environmental Protection Agency 2002b) in the United States. While the vast majority of water and sewer customers are served by large metropolitan systems, most systems are small and located in rural areas. Due to their small size, these rural systems are generally more expensive to build and operate on a per-user basis, and they tend to have more problems complying with environmental and public health requirements. Many of these systems need special help to serve their customers reliably over the long term. Within the last few years, the U.S. Environmental Protection Agency (EPA) commissioned two studies of community water systems. One was the Community Water System Survey 2000 (Rourke and Selby 2002); the other was the Clean Water and Drinking Water Infrastructure Gap Analysis (U.S. Environmental Protection Agency 2002a), commonly referred to as the Gap Analysis. These studies revealed that between the years 2000 and 2020 water and sewer systems in the U.S. will experience a cumulative funding shortfall for operating and capital improvement costs of between 500 and 750 billion dollars. We are now several years into that time frame, and there is little evidence of progress toward erasing the looming shortfall. Without measures to increase revenues and reduce costs, in the next several decades, our water and sewer systems will experience serious financial upsets that may shut some systems down and seriously imperil the operations of many others. The effects will hit small rural systems disproportionately hard. Large systems enjoy economies of scale that allow them to hire financial and other management and planning expertise. They tend to be well funded and managed on a current operations basis. However, they will experience a staggering capital improvements funding shortfall over the next few decades as they replace aging distribution and treatment systems. Small systems, lacking economies of scale, are frequently poorly funded. They will experience the same kinds of funding shortfalls as the large systems. They also commonly operate at a loss on an operating cost basis. Small system managers attempt to manage well, but they are at a distinct disadvantage without proper training, experience, tools, and funding. This paper examines successes in helping small systems, and it highlights opportunities to strengthen the capacity of these systems.

"Total petroleum hydrocarbons" (TPHs) or "petroleum hydrocarbons" (PHCs) are one of the most widespread soil pollutants in Canada, North America, and worldwide. Clean-up of PHC-contaminated soils and sediments costs the Canadian economy hundreds of million of dollars annually. Much of this activity is driven by the need to meet regulated levels of PHC in soil. These PHC values are legally required to be assessed using standard methods. The method most commonly used in Canada, specified by the Canadian Council of Ministers of the Environment (CCME), measures the total hydrocarbon concentrations in a soil by carbon range (Fraction 1: C(6)-C(10); Fraction 2: C(10)-C(16), Fraction 3: C(16)-C(34): and Fraction 4: C(34)+). Using the CCME method, all of the materials extractible by a mixture of 1:1 hexane:acetone are considered to be petroleum hydrocarbon contaminants. Many hydrocarbon compounds and other extractible materials in soil, however, may originate from non-petroleum sources. Biogenic organic compounds (BOCs) is a general term used to describe a mixture of organic compounds, including alkanes, sterols and sterones, fatty acids and fatty alcohols, and waxes and wax esters, biosynthesized by living organisms. BOCs are also produced during the early stages of diagenesis in recent aquatic sediments. BOC sources could include vascular plants, algae, bacteria and animals. Plants and algae produce BOCs as protective wax coating that are released back into the sediment at the end of their life cycle. BOCs are natural components of thriving plant communities. Many solvent-extraction methods for assessing soil hydrocarbons, however, such as the CCME method, do not differentiate PHCs from BOCs. The naturally occurring organics present in soils and wet sediments can be easily misidentified and quantified as regulated PHCs during analysis using such methods. In some cases, biogenic interferences can exceed regulatory levels, resulting in remediation of petroleum impacts that are not actually present. Consequently, reliance on these methods can trigger unnecessary and costly remediation, while also wasting valuable landfill space. Therefore, it is critically important to develop new protocols to characterize and differentiate PHCs and BOCs in contaminated sediments. In this study, a new reliable gas chromatography-mass spectrometry (GC-MS) method, in combination with a derivatization technique, for characterization of various biogenic compounds (including biogenic alkanes, sterols, fatty acids and fatty alcohols) and PHCs in the same sample has been developed. A multi-criteria approach has been developed to positively identify the presence of biogenic compounds in soil and sediment samples. More than thirty sediment samples were collected from city stormwater management (SWM) ponds and wetlands across Canada. In these wet sediment samples, abundant biogenic n-alkanes, thirteen biogenic sterols, nineteen fatty carboxylic acids, and fourteen fatty alcohols in a wide carbon range have been positively identified. Both PHCs and BOCs in these samples were quantitatively determined. The quantitation data will be used for assessment of the contamination sites and toxicity risks associated with the CCME Fraction 3 hydrocarbons.

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.

In the summer of 1996 the oil barge, Irving Whale , was successfully raised from the depths of the St Lawrence River with the majority of its cargo of bunker C fuel oil intact. As part of the recovery effort, the Emergencies Science Division of Environment Canada performed airborne remote sensing flights over the site of the barge prior to, during and following the lift procedure. The primary sensor employed during these remote sensing flights was the laser environmental airborne fluorosensor (LEAF). Additional equipment on board Environment Canada's DC-3 aircraft included an RC-10 colour mapping camera and two down-looking video cameras. In the days leading up to the lifting of the Irving Whale , the LEAF system detected bunker C fuel oil on the surface of the gulf in close proximity to the location of the sunken barge. This oil was believed to have been dislodged from beneath structures on the top of the barge during inspections, welding and other preparations in advance of the lift. On the actual day of the lift, 30 July, greatly increased amounts of bunker fuel were detected. During each overflight, the real-time LEAF system produced timely, concise map-based oil contamination information in hard-copy form. The locations of the visibly thick and recoverable oil were radioed to spill response personnel on the surface and promptly recovered by booming and skimming operations. In addition, the LEAF system found extremely thin, sub-sheen levels of oil over the majority of the southern Gulf of St Lawrence on the day of the lift. The extent of this coverage was greatly reduced the following day (presumably due to further spreading) and essentially eliminated by 1 August. The LEAF system on the DC-3 continued to monitor the Irving Whale as it was transported to Halifax, Nova Scotia on the deck of the submersible vessel Boabarge 10 . During transit no oil which could be attributed to the Irving Whale was detected, apart from a small residual amount at the lift site.

The continued demand for crude oil and related petroleum products along with the resulting upward spiral of the market price of oil have forced oil exploration and production companies to seek out new reserves farther offshore and in deeper waters. The United States is among the top five nations globally in terms of estimated offshore oil reserves and petroleum production. Yet deepwater drilling to extract these reserves is a major engineering challenge for oil companies. Moreover, such drilling activity also comes with a significant environmental risk, and the extremely high pressures associated with deepwater oil wells mean that the mitigation of accidental releases from a deepwater spill is truly a challenging endeavor.

Publisher Summary This chapter outlines several general reviews of oil spill remote sensing. Massive spills of oil and related petroleum products can have serious biological and economic impacts. Following a spill, there is a scrutiny both from public and media with demands that the location and extent of the oil spill be determined. This chapter discusses various sensors. Remote sensing is playing a major role in determining the extent of oil spill. With the help of this instrument, oil can be monitored on the open ocean around the clock. The demerit of this instrument is that it lags behind in technology. Another instrument known as ‘optical sensor’ helps in determining the extent of oil spill. Optical techniques, the most common means of remote sensing uses the same range of the visible spectrum detection. Of late, a new technology which is known as Global Positioning Systems (GPS) is directly used to map remote-sensing data onto base maps. This chapter reviews the future trends of remote sensing such as cameras and thermal IR cameras, laser technology. Also rapidly improving computer capabilities allows real-time processing. Combinations of airborne and satellite-borne sensor systems are recommended in order to respond effectively to major marine oil spills.

Publisher Summary This chapter discusses laser fluorosensors. Laser fluorosensors are capable of detecting oil and related petroleum products in complex marine, coastal, and terrestrial environments. These sensors can discriminate between oiled and unoiled naturally occurring substances such as kelp and seaweed. It is the only sensor that detects a primary characteristic of oil, namely the unique oil fluorescence spectral signature whereas other generic sensors rely on secondary characteristics of oil such as the reflection of light of various wavelengths, scattering of microwaves, and emission of infrared energy. This chapter also highlights the principles of laser fluorosensors operations. The principles of laser fluorosensors operations are classified into active sensors and passive sensors. Passive sensors are those that measure naturally available energy such as rays of the sunlight. On the other hand, active sensors provide their own energy. This chapter reviews two important aspects of oil classifications– Real-Time Analysis and Sensor Outputs. One of the advantages of modern laser fluorosensors is the ability to detect and classify oil contamination in real time. The availability of real-time oil contamination is essential for rapid oil spill response and environmental damage mitigation. The display of spectral data is essential for the effective operation of modern laser fluorosensors which is an important part of sensor output. Improvement in the fields of lasers, solid-state electronics, and computer operating hardware/software continue to fuel the progress of advanced laser fluorosensors.

An electromagnetic model to observe man-made metallic objects in dual-polarized SAR data has been developed. The model predicts that man-made metallic objects and sea surface, being characterized by completely different symmetry properties, call for a different and well-distinguishable HH-HV correlation. Following this rationale, a simple and very computer-time effective filtering technique has been developed to observe man-made metallic objects in full-resolution dual-polarized SAR data. Experiments accomplished over Single Look Complex (SLC) Fine Quad Polarization RADARSAT-2 SAR data confirm the effectiveness of the proposed approach.

A novel technique is described for monitoring transient infrared absorptions with a tunable diode laser (TDL). The technique involves modulating the TDL at frequencies as high as 250 kHz and using both analog and digital subtraction of background signals. Transient absorptions as small as 0.001% can be detected with a response time of a few microseconds. The technique provides excellent discrimination between transient absorption lines and spurious effects such as beam deflection. Transient detection of the CF(2) radical in a photolysis cell is used to illustrate the technique, and a comparison is made with more conventional TDL detection methods. The modulation technique is clearly a very powerful tool for transient infrared spectroscopy.

This study presents a quantitative gas chromatography-mass spectrometry analysis of bicyclic sesquiterpanes (BSs) in numerous crude oils and refined petroleum products including light and mid-range distillate fuels, residual fuels, and lubricating oils collected from various sources. Ten commonly recognized bicyclic sesquiterpanes were determined in all the studied crude oils and diesel range fuels with principal dominance of BS3 (C(15)H(28)), BS5 (C(15)H(28)) and BS10 (C(16)H(30)), while they were generally not detected or in trace in light fuel oils like gasoline and kerosene and most lubricating oils. Laboratory distillation of crude oils demonstrated that sesquiterpanes were highly enriched in the medium distillation fractions of approximately 180 to 481 degrees C and were generally absent or very low in the light distillation fraction (boiling point to approximately 180 degrees C) and the heavy residual fraction (481 degrees C). The effect of evaporative weathering on a series of diagnostic ratios of sesquiterpanes, n-alkanes, and biomarkers was evaluated with two suites of weathered oil samples. The change of abundance of sesquiterpanes was used to determine the extent of weathering of artificially evaporated crude oils and diesel. In addition to the pentacyclic biomarker C(29) and C(30) alphabeta-hopane, C(15) and C(16) sesquiterpanes might be alternative internal marker compounds to provide a direct way to estimate the depletion of oils, particularly diesels, in oil spill investigations. These findings may offer potential applications for both oil identification and oil-source correlation in cases where the tri- to pentacyclic biomarkers are absent due to refining or environmental weathering of oils.

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.

In this paper an artificial neural network (ANN) approach, which is based on flexible nonlinear models for a very broad class of transfer functions, is applied for multi-spectral data analysis and modeling of airborne laser fluorosensor in order to differentiate between classes of oil on water surface. We use three types of algorithm: Perceptron Network, Back-Propagation (B-P) Network and Self-Organizing feature Maps (SOM) Network. Using the data in form of 64-channel spectra as inputs, the ANN presents the analysis and estimation results of the oil type on the basis of the type of background materials as outputs. The ANN is trained and tested using sample data set to the network. The results of the above 3 types of network are compared in this paper. It is proved that the training has developed a network that not only fits the training data, but also fits real-world data that the network will process operationally. The ANN model would play a significant role in the ocean oil-spill identification in the future.

In order to detect and identify oil-spilled on the sea by Airborne Laser-Induced Fluorescence, a fuzzy model and algorithm are put forward in this paper. The target to be detected on the sea may be one of the following: seawater, crude oil, diesel, lubricating oil, dirty water, sand, etc. The primary requirement for airborne sensors is to identify, in real-time, the substances targeted by the laser beam. There have been several algorithms developed for the detection of oil spilled on the sea by Airborne Laser-Induced Fluorescence, for example, the Pearson Correlation Coefficient method. The reason that we have decided to research the fuzzy model for the identification of oils spilled on the sea, is that there are some uncertainties and unknown differences between the “live” spectrum, and the substances targeted by the laser beam. The fuzzy algorithm presented in this paper is based on a fuzzy closeness matrix. All values in the matrix are calculated from the spectrum of a target and the spectra of the above mentioned “pure” substances. This paper outlines the fuzzy model for the identification of the spilled oils, and makes a comparison with the Pearson Correlation Coefficient method in an effort to increase the level of confidence in the identification results and reduce the computational time. The results of ground tests using known targets show an increased confidence with the identification results using the Fuzzy Model when compared to the results of the Pearson Correlation Coefficient Algorithm.

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.

Locating oil in marine and terrestrial environments is a daunting task. There are commercially available off the shelf (COTS) sensors with a wide field-of-view (FOV) which can be used to map the overall extent of the spill. These generic sensors, however, lack the specificity required to positively identify oil and related products. The problem is exacerbated along beach and shoreline environments where a variety of organic and inorganic substrates are present. One sensor that can detect and classify oil in these environments is the laser fluorosensor. Laser fluorosensors have been under development by several agencies around the world for the past two decades. Environment Canada has been involved with laser fluorosensor development since the early 1990s. The prototype system was known as the Laser Environmental Airborne Fluorosensor (LEAF). The LEAF has recently been modified to provide real-time oil spill detection and classification. Fluorescence spectra are collected and analyzed at the rate of 100 Hz. Geo-referenced maps showing the locations of oil contamination are produced in real-time onboard the aircraft. While the LEAF has proven to be an excellent prototype sensor and a good operational tool, it has some deficiencies when it comes to oil spill response operations. A consortium including Environment Canada and the Minerals Management Service has recently funded the development of a new fluorosensor, called the Scanning Laser Environmental Airborne Fluorosensor (SLEAF). The SLEAF was designed to detect and map oil in shoreline environments where other non-specific sensors experience difficulty. Oil tends to pile up in narrow bands along the high tide line on beaches. A nadir-looking, small footprint sensor such as the LEAF would have difficulty locating oil in this situation. The SLEAF employs a pair of conical scanning mirrors to direct the laser beam in a circular pattern below the aircraft. With a sampling rate of 400 Hz and real-time spectral analysis, the SLEAF will detect and map oil contamination in marine and coastal environments. The SLEAF will confirm or reject suspected oil contamination sites that have been targeted by the generic sensors. This confirmation will release response crews from the time-consuming task of physically inspecting each site and instead direct crews to sites that require remediation.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Remote sensing is becoming an increasingly important tool for the effective direction of oil spill countermeasures. Cleanup personnel have recognized that remote sensing can increase spill cleanup efficiency. It has long been recognized that there is no one sensor which is capable of detecting oil and related petroleum products in all environments and spill scenarios. There are sensors which possess a wide field-of- view and can therefore be used to map the overall extent of the spill. These sensors, however lack the capability to positively identify oil and related products, especially along complicated beach and shoreline environments where several substrates are present. The laser-based sensors under development by the Emergencies Science Division of Environment Canada are designed to fill specific roles in oil spill response. The scanning laser environmental airborne fluorosensor (SLEAF) is being developed to detect and map oil and related petroleum products in complex marine and shoreline environments where other non-specific sensors experience difficulty. The role of the SLEAF would be to confirm or reject suspected oil contamination sites that have been targeted by the non-specific sensors. This confirmation will release response crews from the time-consuming task of physically inspecting each site, and direct crews to sites that require remediation. The laser ultrasonic remote sensing of oil thickness (LURSOT) sensor will provide an absolute measurement of oil thickness from an airborne platform. There are presently no sensors available, either airborne or in the laboratory which can provide an absolute measurement of oil thickness. This information is necessary for the effective direction of spill countermeasures such as dispersant application and in-situ burning. This paper describes the development of laser-based airborne oil spill remote sensing instrumentation at Environment Canada and identifies the anticipated benefits of the use of this technology to the oil spill response community.

Remote sensing is becoming an increasingly important tool for the effective direction of oil spill countermeasures.Cleanup personnel have recognized that remote sensing can increase spill cleanup efficiency. The general public expects that thegovernment and/or the spiller know the location and the extent ofthe contamination. The Emergencies Science Division (ESD) ofEnvironment Canada, (Canadian government department), is responsible for remote sensing during oil spill emergencies alongCanada's three coastlines, extensive inland waterways, as well as over the entire land mass. In addition to providing operationalremote sensing, ESD conducts research into the development of airborne oil spill remote sensors, including the Scanning LaserEnvironmental Airborne Fluorosensor (SLEAF) and the Laser Ultrasonic Remote Sensing of Oil Thickness (LURSOT) sensor. Ithas long been recognized that there is no one sensor or "Magic Bullet" which is capable of detecting oil and related petroleumproducts in all environments and spill scenarios. There are sensors which possess a wide field-of-view (FOV) and can therefore beused to map the overall extent of the spill. These sensors, however lack the specificity required to positively identify oil and relatedproducts. This is even more of a problem along complicated beach and shoreline environments where several substrates arepresent.The specific laser-based sensors under development by Environment Canada are designed to respond to special roles inoil spill response. In particular, the Scanning Laser Environmental Airborne Fluorosensor is being developed to unambiguouslydetect and map oil and related petroleum products in complicated marine and shoreline environments where other non-specificsensors experience difficulty. The role of the SLEAF would be to confirm or reject suspected oil contamination sites that have beentargeted by the non-specific sensors. This confirmation will release response crews from the time consuming task of physicallyinspecting each site, and direct crews to sites that require remediation. The Laser Ultrasonic Remote Sensing of Oil Thickness(LURSOT) sensor will provide an absolute measurement of oil thickness from an airborne platform. There are presently nosensors available, either airborne or in the laboratory which can provide an absolute measurement of oil thickness. Thisinformation is necessary for the effective direction of spill countermeasures such as dispersant application and in-situ burning.This paper will describe the development of laser-based airborne oil spill remote sensing instrumentation at EnvironmentCanada and identify the anticipated benefits ofthe use of this technology to the oil spill response community.Keywords : Oil spill, remote sensing, scanning laser environmental airborne fluorosensor, thickness, LEAF, SLEAF,LURSOT.

Total petroleum hydrocarbons (TPH) or petroleum hydrocarbons (PHC) are one of the most widespread soil contaminants in Canada, the United States and many other countries worldwide. Clean-up of PHC-contaminated soils costs the Canadian economy hundreds of millions of dollars annually. In Canada, most PHC-contaminated site evaluations are based on the methods developed by the Canadian Council of the Ministers of the Environment (CCME). However, the CCME method does not differentiate PHC from BOC (the naturally occurring biogenic organic compounds), which are co-extracted with petroleum hydrocarbons in soil samples. Consequently, this could lead to overestimation of PHC levels in soil samples. In some cases, biogenic interferences can even exceed regulatory levels (300 μg g(-1) for coarse soils and 1300 μg g(-1) for fine soils for Fraction 3, C(16)-C(34) range, in the CCME Soil Quality Level). Resulting false exceedances can trigger unnecessary and costly cleanup or remediation measures. Therefore, it is critically important to develop new protocols to characterize and quantitatively differentiate PHC and BOC in contaminated soils. The ultimate objective of this PERD (Program of Energy Research and Development) project is to correct the misconception that all detectable hydrocarbons should be regulated as toxic petroleum hydrocarbons. During 2009-2010, soil and plant samples were collected from over forty oil-contaminated and paired background sites in various provinces. The silica gel column cleanup procedure was applied to effectively remove all target BOC from the oil-contaminated sample extracts. Furthermore, a reliable GC-MS method in combination with the derivatization technique, developed in this laboratory, was used for identification and characterization of various biogenic sterols and other major biogenic compounds in these oil-contaminated samples. Both PHC and BOC in these samples were quantitatively determined. This paper reports the characterization results of this set of 21 samples. In general, the presence of petroleum-characteristic alkylated PAH homologues and biomarkers can be used as unambiguous indicators of the contamination of oil and petroleum product hydrocarbons; while the absence of petroleum-characteristic alkylated PAH homologues and biomarkers and the presence of abundant BOC can be used as unambiguous indicators of the predominance of natural organic compounds in soil samples.

This study used solid phase extraction (SPE) cartridges for rapid cleanup and fractionation of oil samples in oil fingerprinting analysis. A series of commercially available florisil cartridges, normal phase SPE cartridges, and silica gel/cyanopropyl (SiO2/C3-CN) SPE cartridges was selected for the fractionation of oil into aliphatic and aromatic hydrocarbons. The florisil cartridges and normal phase SPE cartridges can clean up the oil samples but are unable to separate them into two fractions. The SiO2/C3-CN (1 g/0.5 g) SPE cartridge successfully separated oil samples into aliphatic and aromatic fractions by eluting with 4 mL of hexane and 4 mL of dichloromethylene (DCM)/hexane (3 : 1, v:v), respectively. No cross-elution was observed between aliphatic and aromatic fractions when oil loading mass was less than 40 mg on the SiO2/C3-CN SPE cartridge. The relative standard deviation (RSD) of five replicates of SPE-GC-MS analysis of 5 mg of reference oil is 2.8%, 1.2%, and 6.9% for total n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and biomarkers, respectively. The recoveries of six spiked deuterated surrogates were all above 95%. This SPE-GC-MS method was used for the fingerprinting analysis of various crude oils, refined petroleum products, and environmental sediment samples. The characterized target hydrocarbons included n-alkanes, unsubstituted priority PAHs and alkylated homologues, and biomarker terpanes and steranes. The concentration profiles and diagnostic ratios of target compounds are both comparable to those obtained by the conventional silica gel column-GC-MS method.

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.

A naturalistic experiment tested the proposition that police time could be saved in nondangerous crisis intervention calls through the use of citizen participants. Results showed that police officers who used citizen intervention spent less time per call than officers who did not. However, police time was not saved in family disturbance calls. Family disturbance control group calls were rated by police as having a higher degree of physical danger present than other calls.

Naphthenic acids (NAs) or naphthenic acid fraction compounds (NAFCs) are generally recognized as a family of cycloaliphatic carboxylic acids naturally occurring in petroleum. These acid extractable organics (AEOs) from petroleum industry activities including oil sands produced waters (OSPW) have led to increasing environmental concern in recent years due to their potential release into the environment. This study presents a characterization of naphthenic acids in a number of crude oils and refined petroleum products from various sources. NAs with unsaturated degree of z −2 to z −24 and carbon number ranging from 6 to 60 were determined by liquid chromatography-high resolution Orbitrap mass spectrometry (LC-HRMS). NA profiles generally vary from oil to oil. Conventional light crude oils generally contain low concentrations of NAs, while heavier crudes and oil sands bitumen contain significant levels of NAs. NAs in Federated and Alaska North Slope crude oils are relatively low with O2-NA concentrations of 139 µg/g and 419 µg/g, respectively, while their abundances are as high as 7994 µg/g in Venezuelan Orinoco bitumen. The ratio of even to odd (E/O) carbon number NAs in all petroleum oils studied is close to 1.0 for z −2 to z −24 NAs. NA series z 0 to z −12 in bitumen account for about 90% of the total determined NAs, and z −14 to z −24 NAs make up the remaining ∼10%. Moreover, z −2∼−6 (1- to 3-ring) NAs are the most predominant in all oil samples. In terms of distribution according to carbon number, C6 to C21 NAs (α-group) make up about 44.2% of the total NAs in an Alberta oil sands bitumen. Caustic extraction of oil sands bitumen mostly transports the more toxic low-molecular weight portion of NAs into OSPW, in which α-group NAs constitute about 90% of the total NAs. Evaporation (up to 23.6% by weight) weathering slightly enriched the NAs but likely did not affect the distribution profile of NAs in a diluted bitumen (dilbit).