Oil Sands Process Research Articles

Harnessing oil sands microbial communities for use in ex situ naphthenic acid bioremediation

The caustic hot water extraction process used to release bitumen from the Alberta oil sands generates large volumes of tailings waste, or oil sands process water (OSPW). OSPW contains several components of environmental concern including diluents, polyaromatic hydrocarbons, heavy metals, and naphthenic acids (NAs); the latter are of particular concern as they are acutely toxic to aquatic organisms and mammals. Studies have demonstrated that the naturally occurring OSPW bacteria are capable of metabolizing the NAs. However, this in situ process takes place over hundreds of years, and is incomplete, leaving a recalcitrant fraction of NAs intact. In this study we explore options for recovering and harnessing the naturally occurring OSPW bacteria for potential future use in an aerobic ex situ OSPW treatment system. Here we evaluate our recovered microbes on their ability to degrade two model NAs, cyclohexane carboxylic acid and cyclohexane acetic acid. Using OSPW as a source for a bacterial inoculum, we were able to compare single and multispecies OSPW cultures, grown as either a biofilm, or as a planktonic suspension. Furthermore, we examined the effect of available nutrients on the ability of these cultures to degrade NAs. All biofilms were grown using the Calgary Biofilm Device. GC–MS, and GC-FID reveal that multispecies biofilm and planktonic cultures are each capable of degrading both NAs; a trait not observed for single species cultures. Moreover, complementary carbon sources have a tangible effect on the ability of the cultures to initiate the degradation of the NAs.

Collaborative Interactions between EO-PO Copolymers upon Mixing

Chemical demulsification is the most extensively used method for breaking water-in-diluted bitumen emulsions in oil sands processing. In this paper, the properties and performance of three demulsifier formulations and their individual EO-PO polymer components were studied. The EO-PO polymers and demulsifier formulations were characterized by their relative solubility number (RSN). The results showed that the RSN is an additive property. The dehydration efficiency of the demulsifier formulation was higher than the individual components at the same dosage, signifying that there were collaborative interactions among the polymers on mixing. Correlations between performance of the demulsifiers and interfacial tension (IFT), yield stress of underflow, and bitumen loss to tailings were investigated. The results showed no correlation between the performance of the demulsifiers and equilibrium IFT. Correlations were observed between dehydration efficiency and both yield stress of the underflow and bitumen loss to ...

Diaromatic sulphur-containing ‘naphthenic’ acids in process waters

Polar organic compounds found in industrial process waters, particularly those originating from biodegraded petroleum residues, include ‘naphthenic acids’ (NA). Some NA have been shown to have acute toxicity to fish and also to produce sub-lethal effects. Whilst some of these toxic effects are produced by identifiable carboxylic acids, acids such as sulphur-containing acids, which have been detected, but not yet identified, may produce others. Therefore, in the present study, the sulphur-containing acids in oil sands process water were studied.A fraction (ca 12% by weight of the total NA containing ca 1.5% weight sulphur) was obtained by elution of methylated NA through an argentation solid phase extraction column with diethyl ether. This was examined by multidimensional comprehensive gas chromatography-mass spectrometry (GCxGC-MS) in both nominal and high resolution mass accuracy modes and by GCxGC-sulphur chemiluminescence detection (GCxGC-SCD).Interpretation of the mass spectra and retention behaviour of methyl esters of several synthesised sulphur acids and the unknowns allowed delimitation of the structures, but not complete identification. Diaromatic sulphur-containing alkanoic acids were suggested.Computer modelling of the toxicities of some of the possible acids suggested they would have similar toxicities to one another and to dehydroabietic acid. However, the sulphur-rich fraction was not toxic or estrogenic to trout hepatocytes, suggesting the concentrations of sulphur acids in this sample were too low to produce any such effects in vitro. Further samples should probably be examined for these compounds.

Diamondoid diacids ('O4' species) in oil sands process‐affected water

As a by-product of oil sands extraction, large volumes of oil sands process water (OSPW) are generated, which are contaminated with a large range of water-soluble organic compounds. The acids are thought to be derived from hydrocarbons via natural biodegradation pathways such as α- and β-oxidation of alkyl substituents, which could produce mono- and diacids, for example. However, while several monoacids ('O2' species) have been identified, the presence of diacids (i.e. 'O4' species) has only been deduced from results obtained via Fourier transform infrared (FTIR) spectroscopy, Fourier transform ion cyclotron resonance high-resolution mass spectrometry (FTICR-HRMS) and nuclear magnetic resonance ((1)H-NMR) spectroscopy and the structures have never been confirmed. An extract of an OSPW from a Canadian tailings pond was analysed and the retention times and the electron ionization mass spectra of some analytes were compared with those of bis-methyl esters of authentic diacids by gas chromatography × gas chromatography/time-of-flight mass spectrometry (GCxGC/TOFMS) in nominal and accurate mass configurations. Two diamondoid diacids (3-carboxymethyladamantane-1-carboxylic acid and adamantane-1,3-dicarboxylic acid) were firmly identified as their bis-methyl esters by retention time and mass spectral matching and several other structural isomers were more tentatively assigned. Diacids have substantially increased polarity over the hydrocarbon and monoacid species from which they probably derive: as late members of biodegradation processes they may be useful indicators of weathering and ageing, not only of OSPW, but potentially of crude oil residues more generally. Structures of O4 species in OSPW have been identified. This confirms pathways of microbial biodegradation, which were only postulated previously, and may be a further indication that remediation of OSPW toxicity can occur by natural microbial action. The presence and abundance of these diacids might therefore be useful as a measure of biodegradation and weathering.

Integration of reclamation and tailings management in oil sands surface mine planning

The processing of oil sands generates large volumes of slurry, known as tailings, that is impounded in tailings ponds. Oil sands operators are committed to develop reclamation plans to ensure that the mine site is restored to a natural or economically usable landscape. Since most of the material that is needed for capping of the tailings pond is produced in mining operation, it is reasonable to include material requirement for reclamation as part of mine planning. In this paper, an integrated long-term mine planning model is proposed that includes tailings capacity and reclamation material requirements. A mixed integer linear programming (MILP) model is developed to test the performance of the proposed model. The MILP model is coded in Matlab®. It is verified by carrying out a case study on an actual oil sands dataset, and has resulted in an integer solution within a 2% gap to the optimality. The resulted production schedule meets the capacity constraint of the tailings facility and guarantees the production of the required reclamation material.

Potential for in situ chemical oxidation of acid extractable organics in oil sands process affected groundwater

The process of bitumen extraction from oil sands in Alberta, Canada leads to an accumulation of toxic acid-extractable organics (AEOs) in oil sands process water (OSPW). Infiltration of OSPW from tailings ponds and from their retaining sand dykes and subsequent transport towards surface water has occurred. Given the apparent lack of significant natural attenuation of AEOs in groundwater, remediation may be required. This laboratory study evaluates the potential use of unactivated persulfate and permanganate as in situ oxidation agents for remediation of AEOs in groundwater. Naphthenic acids (NAs; CnH2n+zO2), which are a component of the acutely toxic AEOs, were degraded by both oxidants in OSPW samples. Permanganate oxidation yielded some residual dissolved organic carbon (DOC) whereas persulfate mineralized the AEO compounds with less residual DOC. Acid-extractable organics from oxidized OSPW had essentially no Microtox toxicity.

Hot water generation for oil sands processing from enhanced geothermal systems: Process simulation for different hydraulic fracturing scenarios

The oil sands in northern Alberta, Canada are home to one of the largest hydrocarbon deposits on earth. Huge amounts of hot water—around 50–60°C—are needed for the current extraction procedure and processing technology. The current practice of obtaining water from the Athabasca River and heating it by the burning of natural gas creates severe economic and environmental costs. In fact, 6% of Canada’s gas consumption is used for this purpose. As seen, the generation of huge amounts of fossil energy through oil sands extraction requires a substantial amount of fossil energy consumption (natural gas). Geothermal energy has the potential to significantly reduce natural gas consumption and greenhouse gas emissions at competitive costs.In this paper, we investigate how and whether or not the required hot water can be generated from the granitic basement rocks beneath the oil sands mining areas near Fort (Ft.) McMurray, located in the north east of Alberta. Hydraulic fracturing and resulting reservoir scenarios were simulated for different expected conditions in the region in order to find suitable fracturing strategies and conditions for an Enhanced Geothermal System (EGS). The simulations show that suitable fracturing treatments can increase the hydraulic performance of the system and that EGS heat generation can significantly reduce the environmental impact at comparable costs associated with the current processing technology. With this effort, significant reductions in greenhouse gas emissions and natural gas consumption can be achieved.

Chemical fingerprinting of naphthenic acids and oil sands process waters—A review of analytical methods for environmental samples

This article provides a review of the routine methods currently utilized for total naphthenic acid analyses. There is a growing need to develop chemical methods that can selectively distinguish compounds found within industrially derived oil sands process affected waters (OSPW) from those derived from the natural weathering of oil sands deposits. Attention is thus given to the characterization of other OSPW components such as oil sands polar organic compounds, PAHs, and heavy metals along with characterization of chemical additives such as polyacrylamide polymers and trace levels of boron species. Environmental samples discussed cover the following matrices: OSPW containments, on-lease interceptor well systems, on- and off-lease groundwater, and river and lake surface waters. There are diverse ranges of methods available for analyses of total naphthenic acids. However, there is a need for inter-laboratory studies to compare their accuracy and precision for routine analyses. Recent advances in high- and medium-resolution mass spectrometry, concomitant with comprehensive mass spectrometry techniques following multi-dimensional chromatography or ion-mobility separations, have allowed for the speciation of monocarboxylic naphthenic acids along with a wide range of other species including humics. The distributions of oil sands polar organic compounds, particularly the sulphur containing species (i.e., OxS and OxS2) may allow for distinguishing sources of OSPW. The ratios of oxygen- (i.e., Ox) and nitrogen-containing species (i.e., NOx, and N2Ox) are useful for differentiating organic components derived from OSPW from natural components found within receiving waters. Synchronous fluorescence spectroscopy also provides a powerful screening technique capable of quickly detecting the presence of aromatic organic acids contained within oil sands naphthenic acid mixtures. Synchronous fluorescence spectroscopy provides diagnostic profiles for OSPW and potentially impacted groundwater that can be compared against reference groundwater and surface water samples. Novel applications of X-ray absorption near edge spectroscopy (XANES) are emerging for speciation of sulphur-containing species (both organic and inorganic components) as well as industrially derived boron-containing species. There is strong potential for an environmental forensics application of XANES for chemical fingerprinting of weathered sulphur-containing species and industrial additives in OSPW.

Elemental and spectroscopic characterization of fractions of an acidic extract of oil sands process water

‘Naphthenic acids’ (NAs) in petroleum produced water and oil sands process water (OSPW), have been implicated in toxicological effects. However, many are not well characterized. A method for fractionation of NAs of an OSPW was used herein and a multi-method characterization of the fractions conducted.The unfractionated OSPW acidic extract was characterized by elemental analysis, electrospray ionization-Orbitrap-mass spectrometry (ESI-MS), and an esterified extract by Fourier Transform infrared (FTIR) and ultraviolet–visible (UV) absorption spectroscopy and by comprehensive multidimensional gas chromatography–MS (GCxGC–MS). Methyl esters were fractionated by argentation solid phase extraction (Ag+ SPE) and fractions eluting with: hexane; diethyl ether: hexane and diethyl ether, examined. Each was weighed, examined by elemental analysis, FTIR, UV, GC–MS and GCxGC–MS (both nominal and high resolution MS). The ether fraction, containing sulfur, was also examined by GCxGC–sulfur chemiluminescence detection (GCxGC–SCD).The major ions detected by ESI-MS in the OSPW extract were assigned to alicyclic and aromatic ‘O2’ acids; sulfur was also present. Components recovered by Ag+ SPE were also methyl esters of alicyclic and aromatic acids; these contained little sulfur or nitrogen. FTIR spectra showed that hydroxy acids and sulfoxides were absent or minor. UV spectra, along with the C/H ratio, further confirmed the aromaticity of the hexane:ether eluate.The more minor ether eluate contained further aromatics and 1.5% sulfur. FTIR spectra indicated free carboxylic acids, in addition to esters. Four major sulfur compounds were detected by GCxGC–SCD. GCxGC–high resolution MS indicated these were methyl esters of C18 S-containing, diaromatics with ⩾C3 carboxylic acid side chains.

Oil mobilisation by subcritical water processing

As water approaches the critical point, the dielectric constant lowers enabling solution of heavy oil components. Simultaneously, enhanced water dissociation enhances cracking to lighter fractions. We evaluated this effect for three heavy oils concentrating on the effect of processing on feed viscosity. Reductions of up to 90 % were observed and these could be achieved in a few hours. Although more applicable to surface processing of oil sands in the short term, ultimately this technique could also be applied to immature oils for in situ processing and recovery. This may already be happening in some steam-assisted gravity drainage scenarios. In situ application would be limited to reservoirs where formation pressure is higher than the pressure required to generate these subcritical effects.

Rapid dewatering of oil sand mature fine tailings using super absorbent polymer (SAP)

The Canadian oil sands resources present one of the world’s most vast hydrocarbon deposits. The processing of oil sands to extract bitumen generates large volumes of mature fine tailings (MFT). The large volume, poor consolidation and water release ability of MFT have been causing significant economic and environmental concerns. Therefore, significant research efforts have been devoted to finding methods for the dewatering and densification of MFT. In the present paper, a novel approach which consists of the rapid dewatering of MFT by using a super absorbent polymer (SAP) to produce dense MFT is proposed. A comprehensive laboratory investigation on the shear strength testing of MFT specimens dewatered with SAP by using a vane shear apparatus is conducted. Furthermore, the effect of freeze–thaw cycles on the undrained shear strength of the dewatered MFT is studied. Finally, the ability of recycled SAP to dewater and densify MFT is also assessed. Promising results have been obtained. The results indicate that SAP has the ability to significantly dewater, densify and increase the undrained shear strength of MFT. Furthermore, when subjected to freeze–thaw cycles, the MFT dewatered with SAP shows an additional increase in strength and solid content. It is also found that it is possible to regenerate the polymer (still within sachets) through light thermal drying, and the regenerated SAP can still significantly dewater and thus increase the shear strength and solid content of MFT. Therefore, SAP regeneration and the use of regenerated SAP to dewater MFT in a cost-effective way should be assessed in further studies.

Food web structure in oil sands reclaimed wetlands

Boreal wetlands play an important role in global carbon balance. However, their ecosystem function is threatened by direct anthropogenic disturbance and climate change. Oil sands surface mining in the boreal regions of Western Canada denudes tracts of land of organic materials, leaves large areas in need of reclamation, and generates considerable quantities of extraction process-affected materials. Knowledge and validation of reclamation techniques that lead to self-sustaining wetlands has lagged behind development of protocols for reclaiming terrestrial systems. It is important to know whether wetlands reclaimed with oil sands process materials can be restored to levels equivalent to their original ecosystem function. We approached this question by assessing carbon flows and food web structure in naturally formed and oil sands-affected wetlands constructed in 1970-2004 in the postmining landscape. We evaluated whether a prescribed reclamation strategy, involving organic matter amendment, accelerated reclaimed wetland development, leading to wetlands that were more similar to their natural marsh counterparts than wetlands that were not supplemented with organic matter. We measured compartment standing stocks for bacterioplankton, microbial biofilm, macrophytes, detritus, and zoobenthos; concentrations of dissolved organic carbon and residual naphthenic acids; and microbial production, gas fluxes, and aquatic-terrestrial exports (i.e., aquatic insect emergence). The total biomass of several biotic compartments differed significantly between oil sands and reference wetlands. Submerged macrophyte biomass, macroinvertebrate trophic diversity, and predator biomass and richness were lower in oil sands-affected wetlands than in reference wetlands. There was insufficient evidence to conclude that wetland age and wetland amendment with peat-mineral mix mitigate effects of oil sands waste materials on the fully aquatic biota. Although high variability was observed within most compartments, our data show that 20-year-old wetlands containing oil sands material have not yet reached the same level of function as their reference counterparts.

Effects of crosslinking in demulsifiers on their performance

AbstractChemical demulsification is the most widely used method for breaking water‐in‐diluted bitumen emulsions in oil sands processing. In this work, the properties and performance of six ethylene oxide (EO)–propylene oxide (PO) demulsifiers from three families were investigated. The demulsifiers were characterised by their relative solubility number (RSN) and number of EO–PO branches. The results showed that the performance of the demulsifiers is correlated to the starting base compound, number of EO–PO branches, RSN, oil/water interfacial tension (IFT), increase of molecular weight (MW) by incorporation of crosslinks in EO–PO branches and yield stress of underflow. An increase in MW by the incorporation of crosslinks in EO–PO block copolymers decreased the RSN value while improved the dehydration efficiency. Dynamic IFT measurements revealed that the higher adsorption of EO–PO block copolymers at the oil/water interface on crosslinking, which resulted in higher dehydration efficiencies. The yield stress of the underflow increased on crosslinking the EO–PO block copolymers due to the release of more water and solids to the underflow, which increased the number of aggregates present in the underflow, resulting in increased immobility and constriction and higher yield stress.

Production of heavy minerals concentrate and bitumen from oil sands froth treatment tailings

AbstractIn producing valuable heavy minerals, including zircon and those bearing titanium dioxide, into a heavy minerals concentrate (HMC), the key technical challenges involve bitumen removal from mineral particle surfaces, rejection of fine gangue and recovery of residual solvent. (Organics and fines contamination severely sours downstream heavy minerals production performance). This is accomplished in a manner that is both conducive and integral with oil sands current bitumen production and processing operations. The Company's research and development efforts are based on sophisticated variations of common unit operations, including flotation, solvent extraction and vapour‐phase stripping. Experimentation has indicated optimal design parameters for these unit operations. A large‐scale physical demonstration was completed with performance that has met or exceeded expectations and, after several months of operation, commercial benefits arising from these novel processes have largely been confirmed and validated. Clean HMC with attractive mineralogy is produced containing residual bitumen values sufficiently low to affect high downstream recoveries of zircon (and titania), while producing coker‐feed quality bitumen.

Quantitative analysis of naphthenic acids in water by liquid chromatography–accurate mass time-of-flight mass spectrometry

This study details the development of a routine method for quantitative analysis of oil sands naphthenic acids, which are a complex class of compounds found naturally and as contaminants in oil sands process waters from Alberta's Athabasca region. Expanding beyond classical naphthenic acids (CnH2n−zO2), those compounds conforming to the formula CnH2n−zOx (where 2≥x≤4) were examined in commercial naphthenic acid and environmental water samples. HPLC facilitated a five-fold reduction in ion suppression when compared to the more commonly used flow injection analysis. A comparison of 39 model naphthenic acids revealed significant variability in response factors, demonstrating the necessity of using naphthenic acid mixtures for quantitation, rather than model compounds. It was also demonstrated that naphthenic acidic heterogeneity (commercial and environmental) necessitates establishing a single NA mix as the standard against which all quantitation is performed. The authors present the first ISO17025 accredited method for the analysis of naphthenic acids in water using HPLC high resolution accurate mass time-of-flight mass spectrometry. The method detection limit was 1mg/L total oxy-naphthenic acids (Sigma technical mix).

Limitation of fluorescence spectrophotometry in the measurement of naphthenic acids in oil sands process water

Fluorescence spectrophotometry has been proposed as a quick screening technique for the measurement of naphthenic acids (NAs). To evaluate the feasibility of this application, the fluorescence emission spectra of NAs extracted from three oil sands process water sources were compared with that of commercial NAs. The NAs resulting from the bitumen extraction process cannot be differentiated because of the similarity of the fluorescence spectra. Separation of the fluorescent species in NAs using high performance liquid chromatography with fluorescence detector proved unsuccessful. The acidic fraction of NAs is fluorescent but the basic fraction of NAs is not fluorescent, implying that aromatic acids in NAs give rise to the fluorescent signals. The concentrations of NAs in oil sands process water were measured by Fourier transform infrared spectroscopy (FTIR), fluorescence spectrophotometry and ultra high performance liquid chromatography-time of flight/mass spectrometry (UPLC-TOF/MS). Commercial Merichem and Kodak NAs are the best standards to use when measuring NAs concentration with FTIR and fluorescence spectrophotometry. In addition, the NAs concentrations measured by fluorescence spectrophotometry are about 30 times higher than those measured by FTIR and UPLC-TOF/MS. The findings in this study underscore the limitation of fluorescence spectrophotometry in the measurement of NAs.

Fen mosses can tolerate some saline conditions found in oil sands process water

Mosses are keystone species in peatlands and are an important part of the vegetation of the pre-mined peatlands. Therefore, mosses should be included in rehabilitation projects following oil sands exploitation in north-western Canada. However, mosses growing in post-mined landscapes must tolerate elevated salinity levels found in oil sands process water (OSPW). Knowledge of salinity tolerance and thresholds for fen mosses is needed to place these mosses in the newly created landscapes. We tested the effects of NaCl and Na2SO4 on four fen moss species growing in Petri dishes in growth chambers. We simulated two scenarios: (1) four immersion times (¼, 1, 3 and 7 days) in NaCl (0%, 20%, 60% or 100% of the concentration found in OSPW) mimicking periodic flooding and (2) a permanent saline influence (NaCl or Na2SO4 alone or in combination at 0%, 30%, 50% or 70% of the concentrations found in OSPW) mimicking situations of high water tables with different contamination levels. The effects on moss growth were estimated by counting new innovations of Bryum pseudotriquetrum, Campylium stellatum, Sphagnum warnstorfii and Tomenthypnum nitens. All tested mosses tolerated saline levels typically found in post-mined landscapes (up to 500mgL−1 of NaCl and 400mgL−1 of Na2SO4) for up to 100 days of exposure. Short periods of immersion (up to 7 days independently of salt concentrations) induced the production of innovation in non-Sphagnum species, but S. warnstorfii was more rapidly impacted at higher salt concentrations. Short pulses of salt (from 6h to 7 days) did not influence the formation of new innovations for C. stellatum and T. nitens. Salt type (NaCl and/or Na2SO4) had no effect on moss growth. However, a longer exposure (100 days) with saline water, even at low concentrations, diminished the formation of new innovations for B. pseudotriquetrum and T. nitens. C. stellatum was the least affected by salinity and thus we suggest it is the best species to reintroduce in constructed fens.

Using Infrastructure Optimization to Reduce Greenhouse Gas Emissions from Oil Sands Extraction and Processing

The Alberta oil sands are a significant source of oil production and greenhouse gas emissions, and their importance will grow as the region is poised for decades of growth. We present an integrated framework that simultaneously considers economic and engineering decisions for the capture, transport, and storage of oil sands CO(2) emissions. The model optimizes CO(2) management infrastructure at a variety of carbon prices for the oil sands industry. Our study reveals several key findings. We find that the oil sands industry lends itself well to development of CO(2) trunk lines due to geographic coincidence of sources and sinks. This reduces the relative importance of transport costs compared to nonintegrated transport systems. Also, the amount of managed oil sands CO(2) emissions, and therefore the CCS infrastructure, is very sensitive to the carbon price; significant capture and storage occurs only above 110$/tonne CO(2) in our simulations. Deployment of infrastructure is also sensitive to CO(2) capture decisions and technology, particularly the fraction of capturable CO(2) from oil sands upgrading and steam generation facilities. The framework will help stakeholders and policy makers understand how CCS infrastructure, including an extensive pipeline system, can be safely and cost-effectively deployed.

Lake Data Reveal Oil Sands Impacts

New measurements on the ecological impact of Canadian oil sands mining and processing operations have provided the first clear evidence that concentrations of toxic polycyclic aromatic hydrocarbons (PAHs) are on the rise in the wilderness environment of northern Alberta. The findings may lead to tighter oil sands emissions controls on PAHs, mercury, CO2, and other pollutants. Using a combination of radioisotope dating and mass spectrometry to analyze sediment layers in core samples from six small lakes, researchers say they have recorded levels of anthracenes, pyrenes, and dibenzothiophenes up to 23 times greater than natural background levels, and they are rising (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.1217675110). Scant environmental monitoring data have been collected in northern Alberta since commercial extraction and processing operations began there in the 1960s. The study was carried out by Joshua Kurek and John P. Smol of Queens University, in Kingston, Ontario, along with colleagues from ...

Development of a rapid liquid chromatography tandem mass spectrometry method for screening of trace naphthenic acids in aqueous environments

Over the past 20 years, oil sands exploration and processing in Canada have grown steadily, leading to the development of intensive large-scale operations in Alberta, Canada. Naphthenic acids (NAs), a complex mixture of aliphatic and alicyclic carboxylic acids, are by-products of oil sands processing and are known to be toxic. While oil sands processing water (OSPW) is contained in tailings ponds, potential seepage and leaking of OSPW and its contaminants into surrounding surface water systems is a concern. The ability to quantify NAs and their isomers in OSPW surrounding water is essential for monitoring these spills. Unfortunately, quantification of NAs and their isomers is challenging due to the complexity of the NA mixtures, the lack of commercially available standards, and interference from naturally occurring NA compounds. Techniques such as FT-IR and GC/MS are currently used to analyse NAs, but are limited by poor sensitivity and specificity in the case of FT-IR and long sample preparation and instrument run time for GC/MS. To tackle these issues, a rapid LC/MS method was developed which can quickly quantify NAs in surface water with much better sensitivity and specificity than current methods. This method uses large volume injection, ESI negative mode and a Poroshell LC column to improve the method limits of detection (LOD) and quantitation (LOQ). The method is robust and has no complicated sample preparation steps. The method detection limit (MDL) is 0.01mg/L (10ppb) and low limit of quantitation (LLOQ) of 0.1mg/L (100ppb), both for surface water. The developed method was tested with samples from the oil sands producing region, and demonstrated its applicability for fast screening of surface water samples before resorting to costly high accuracy and high resolution mass spectrometry determination. This is the first very rapid LC/MS method using large volume single column direct injection for quantitative determination of naphthenic acids in surface water.