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Guan J, Huang J, Sun Y, Li C, Wan Y, Wei G, Kang R, Pang H, Shi Q, McHugh T, Ma J. Understanding petroleum vapor fate and transport through high resolution analysis of two distinct vapor plumes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169464. [PMID: 38123082 DOI: 10.1016/j.scitotenv.2023.169464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/09/2023] [Accepted: 12/16/2023] [Indexed: 12/23/2023]
Abstract
No field study has provided a detailed characterization of the molecular composition and spatial distribution of a vadose zone plume of petroleum volatile organic compounds (VOCs), which is critical to improve the current understanding of petroleum VOC transport and fate. This is study reports a high-resolution analysis of two distinct vapor plumes emanating from two different light non-aqueous phase liquid (LNAPL) sources (an aliphatic-rich LNAPL for Zone #1vs an aromatic-rich LNAPL for Zone #2) at a large petrochemical site. Although deep soil vapor signatures were similar to the source zone LNAPL signatures, the composition of the shallow soil vapors reflected preferential attenuation of certain hydrocarbons over others during upward transport in the vadose zone. Between deeper and shallower soil gas samples, attenuation of aromatics was observed under all conditions, but important differences were observed in attenuation to aliphatic compound classes. Attenuation of all aliphatic compounds was observed under aerobic conditions but little attenuation of any aliphatics was observed under anoxic conditions without methane. In contrast, under methanogenic conditions, paraffins attenuated more than isoparaffins and naphthenes. These results suggest that isoparafins and naphthenes may present more of a vapor intrusion risk than benzene or other aromatic hydrocarbons commonly considered to be petroleum vapor intrusion risk drivers. While the overall vapor composition changed significantly within the vadose zone, diagnostic ratios of relatively recalcitrant alkylcyclopentanes were preserved in shallow soil vapor samples. These alkylcyclopentanes may be useful for distinguishing between petroleum vapor intrusion and other sources of petroleum VOCs detected in indoor air.
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Affiliation(s)
- Junjie Guan
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Jierui Huang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Yue Sun
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Chong Li
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Yuruo Wan
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Guo Wei
- Beijing Beitou Eco-environment Co., Ltd, Canal East St. 6th, Beijing 101117, China
| | - Rifeng Kang
- Beijing Beitou Eco-environment Co., Ltd, Canal East St. 6th, Beijing 101117, China
| | - Hongwei Pang
- Beijing Beitou Eco-environment Co., Ltd, Canal East St. 6th, Beijing 101117, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China
| | - Thomas McHugh
- GSI Environmental Inc., 2211 Norfolk Street, Suite 1000, Houston, TX 77098, USA
| | - Jie Ma
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China; College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China.
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Mindorff LM, Mahmoudi N, Hepditch SLJ, Langlois VS, Alam S, Martel R, Ahad JME. Isotopic and microbial evidence for biodegradation of diluted bitumen in the unsaturated zone. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 322:121170. [PMID: 36736816 DOI: 10.1016/j.envpol.2023.121170] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 01/23/2023] [Accepted: 01/28/2023] [Indexed: 06/18/2023]
Abstract
The oil sands region in Western Canada is one of the world's largest proven oil reserves. To facilitate pipeline transport, highly viscous oil sands bitumen is blended with lighter hydrocarbon fractions to produce diluted bitumen (dilbit). Anticipated increases in dilbit production and transport raise the risk of inland spills. To understand the behaviour of dilbit in the unsaturated or vadose zone following a surface spill, we ran parallel dilbit and conventional heavy crude exposures, along with an untreated control, using large soil-filled columns over 104 days. Phospholipid fatty acids (PLFAs), biomarkers for the active microbial population, were extracted from column soil cores. Stable carbon isotope contents (δ13C) of individual PLFAs and radiocarbon contents (Δ14C) of bulk PLFAs were characterized over the course of the experiment. The Δ14CPLFA values in soils impacted by dilbit (-221.1 to -54.7‰) and conventional heavy crude (-259.4 to -97.9‰) indicated similar levels of microbial uptake of fossil carbon. In contrast, Δ14CPLFA values in the control column (-46.1 to +53.7‰) reflected assimilation of more recently fixed organic carbon. Sequencing of 16S ribosomal RNA genes extracted from soil cores revealed a significant increase in the relative abundance of Polaromonas, a known hydrocarbon-degrader, following exposure to both types of oil. This study demonstrates that in the first several months following a surface spill, dilbit has a similar potential for biodegradation by a native shallow subsurface microbial community as conventional heavy crude oil.
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Affiliation(s)
- Leah M Mindorff
- Department of Earth and Planetary Sciences, McGill University, Montréal, QC, H3A 0E8, Canada; Geological Survey of Canada, Natural Resources Canada, Québec, QC, G1K 9A9, Canada
| | - Nagissa Mahmoudi
- Department of Earth and Planetary Sciences, McGill University, Montréal, QC, H3A 0E8, Canada
| | - Scott L J Hepditch
- Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, Québec, QC, G1K 9A9, Canada
| | - Valerie S Langlois
- Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, Québec, QC, G1K 9A9, Canada
| | - Samrat Alam
- Geological Survey of Canada, Natural Resources Canada, Québec, QC, G1K 9A9, Canada
| | - Richard Martel
- Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, Québec, QC, G1K 9A9, Canada
| | - Jason M E Ahad
- Geological Survey of Canada, Natural Resources Canada, Québec, QC, G1K 9A9, Canada.
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3
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Utting N, Namsechi B, McMullen C, Brydie J, Ahad JME. Comparing simulated shallow subsurface spills of diluted bitumen and conventional crude oil. JOURNAL OF CONTAMINANT HYDROLOGY 2022; 251:104099. [PMID: 36369109 DOI: 10.1016/j.jconhyd.2022.104099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 10/17/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Increased oil production in Canada has resulted in proposals to extend or develop new oil pipelines. Many of these proposals have been met by concerns from the public over potential environmental impacts related to construction and the potential for oil spills to negatively affect groundwater quality. Crude oil sourced from the Alberta oil sands represents a significant proportion of this increase in production. This crude oil is produced as bitumen, which is subsequently diluted with light hydrocarbons to lower viscosity to allow for pipeline transport producing diluted bitumen. In this study, we pumped water through tanks filled with sand to simulate groundwater flow. Tanks were injected with either conventional crude or diluted bitumen to simulate a crude oil spill from a pipeline rupture occurring below the water table representing a pipeline river crossing scenario. Water samples were collected from the downstream end of the tanks throughout the experiment period (∼two months). Compared to water quality guidelines, effluent waters from both conventional crude and diluted bitumen tanks contained elevated concentrations of dissolved organic compounds, particularly benzene, ethylbenzene, toluene and xylenes (BTEX). The effluent from each tank had similar concentrations of benzene, whereas discharge water from conventional crude tanks contained higher concentrations of ethylbenzene, toluene and xylenes. In both tanks, and as expected, the BTEX concentrations appeared to be proportional to those determined in their injected crude oils. The measured dissolved concentrations of benzene, ethylbenzene and toluene are lower than predicted which is attributed largely due to dilution along the flow path. In addition to organic constituents, effluent sampled from the diluted bitumen tank contained some metals (Co, Cr, Fe and V) which measured constituents of the oil.
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Affiliation(s)
- Nicholas Utting
- Natural Resources Canada, CanmetENERGY in Devon, 1 Oil Patch Dr, Devon, AB T9G 1A8, Canada.
| | - Behnam Namsechi
- Natural Resources Canada, CanmetENERGY in Devon, 1 Oil Patch Dr, Devon, AB T9G 1A8, Canada
| | - Craig McMullen
- Natural Resources Canada, CanmetENERGY in Devon, 1 Oil Patch Dr, Devon, AB T9G 1A8, Canada
| | - James Brydie
- Natural Resources Canada, CanmetENERGY in Devon, 1 Oil Patch Dr, Devon, AB T9G 1A8, Canada
| | - Jason M E Ahad
- Natural Resources Canada, Geological Survey of Canada, 490 rue de la Couronne, Québec, Québec G1K 9A9, Canada
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Natural Source Zone Depletion (NSZD) Quantification Techniques: Innovations and Future Directions. SUSTAINABILITY 2022. [DOI: 10.3390/su14127027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Natural source zone depletion (NSZD) is an emerging technique for sustainable and cost-effective bioremediation of light non-aqueous phase liquid (LNAPL) in oil spill sites. Depending on regulatory objectives, NSZD has the potential to be used as either the primary or sole LNAPL management technique. To achieve this goal, NSZD rate (i.e., rate of bulk LNAPL mass depletion) should be quantified accurately and precisely. NSZD has certain characteristic features that have been used as surrogates to quantify the NSZD rates. This review highlights the most recent trends in technology development for NSZD data collection and rate estimation, with a focus on the operational and technical advantages and limitations of the associated techniques. So far, four principal techniques are developed, including concentration gradient (CG), dynamic closed chamber (DCC), CO2 trap and thermal monitoring. Discussions revolving around two techniques, “CO2 trap” and “thermal monitoring”, are expanded due to the particular attention to them in the current industry. The gaps of knowledge relevant to the NSZD monitoring techniques are identified and the issues which merit further research are outlined. It is hoped that this review can provide researchers and practitioners with sufficient information to opt the best practice for the research and application of NSZD for the management of LNAPL impacted sites.
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Sookhak Lari K, Davis GB, Rayner JL. Towards a digital twin for characterising natural source zone depletion: A feasibility study based on the Bemidji site. WATER RESEARCH 2022; 208:117853. [PMID: 34800855 DOI: 10.1016/j.watres.2021.117853] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/05/2021] [Accepted: 11/06/2021] [Indexed: 06/13/2023]
Abstract
Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) may be a valid long-term management option at petroleum impacted sites. However, its future long-term reliability needs to be established. NSZD includes partitioning, biotic and abiotic degradation of LNAPL components plus multiphase fluid dynamics in the subsurface. Over time, LNAPL components are depleted and those partitioning to various phases change, as do those available for biodegradation. To accommodate these processes and predict trends and NSZD over decades to centuries, for the first time, we incorporated a multi-phase multi-component multi-microbe non-isothermal approach to representatively simulate NSZD at field scale. To validate the approach we successfully mimic data from the LNAPL release at the Bemidji site. We simulate the entire depth of saturated and unsaturated zones over the 27 years of post-release measurements. The study progresses the idea of creating a generic digital twin of NSZD processes and future trends. Outcomes show the feasibility and affordability of such detailed computational approaches to improve decision-making for site management and restoration strategies. The study provided a basis to progress a computational digital twin for complex subsurface systems.
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Affiliation(s)
- Kaveh Sookhak Lari
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027, Australia.
| | - Greg B Davis
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; School of Earth Sciences, The University of Western Australia, 35 Stirling Highway, Crawley,WA 6009, Australia
| | - John L Rayner
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia
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O'Reilly KT, Sihota N, Mohler RE, Zemo DA, Ahn S, Magaw RI, Devine CE. Orbitrap ESI-MS evaluation of solvent extractable organics from a crude oil release site. JOURNAL OF CONTAMINANT HYDROLOGY 2021; 242:103855. [PMID: 34265523 DOI: 10.1016/j.jconhyd.2021.103855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/23/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
The concentrations of oxygen-containing organic compounds (OCOC), measured as dissolved organic carbon (DOC), in groundwater exceeds those of dissolved hydrocarbons, measured as total petroleum hydrocarbons (TPH), at a crude oil release site. Orbitrap mass spectrometry was used to characterize OCOC in samples of the oil, water from upgradient of the release, source area, and downgradient wells, and a local lake. Chemical characterization factors included carbon number, oxygen number, formulae similarity, double bond equivalents (DBE) and radiocarbon dating. Oil samples were dominated by formulae with less than 30 carbons, four or fewer oxygens, and a DBE of less than four. In water samples, formulae were identified with more than 30 carbons, more than 10 oxygens, and a DBE exceeding 30. These characteristics are consistent with DOC found in unimpacted water. Between 65% and 92% of the formulae found in samples collected within the elevated OCOC plume were also found in the upgradient or surface water samples. Evidence suggests that many of the OCOC are not petroleum degradation intermediates, but microbial products generated as a result of de novo synthesis by organisms growing on carbon supplied by the oil. Implications of these results for understanding the fate and managing the risk of hydrocarbons in the subsurface are discussed.
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Podgorski DC, Zito P, Kellerman AM, Bekins BA, Cozzarelli IM, Smith DF, Cao X, Schmidt-Rohr K, Wagner S, Stubbins A, Spencer RGM. Hydrocarbons to carboxyl-rich alicyclic molecules: A continuum model to describe biodegradation of petroleum-derived dissolved organic matter in contaminated groundwater plumes. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123998. [PMID: 33254831 DOI: 10.1016/j.jhazmat.2020.123998] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 08/17/2020] [Accepted: 09/13/2020] [Indexed: 06/12/2023]
Abstract
Relationships between dissolved organic matter (DOM) reactivity and chemical composition in a groundwater plume containing petroleum-derived DOM (DOMHC) were examined by quantitative and qualitative measurements to determine the source and chemical composition of the compounds that persist downgradient. Samples were collected from a transect down the core of the plume in the direction of groundwater flow. An exponential decrease in dissolved organic carbon concentration resulting from biodegradation along the transect correlated with a continuous shift in fluorescent DOMHC from shorter to longer wavelengths. Moreover, ultrahigh resolution mass spectrometry showed a shift from low molecular weight (MW) aliphatic, reduced compounds to high MW, unsaturated (alicyclic/aromatic), high oxygen compounds that are consistent with carboxyl-rich alicyclic molecules. The degree of condensed aromaticity increased downgradient, indicating that compounds with larger, conjugated aromatic core structures were less susceptible to biodegradation. Nuclear magnetic resonance spectroscopy showed a decrease in alkyl (particularly methyl) and an increase in aromatic/olefinic structural motifs. Collectively, data obtained from the combination of these complementary analytical techniques indicated that changes in the DOMHC composition of a groundwater plume are gradual, as relatively low molecular weight (MW), reduced, aliphatic compounds from the oil source were selectively degraded and high MW, alicyclic/aromatic, oxidized compounds persisted.
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Affiliation(s)
- David C Podgorski
- Pontchartrain Institute for Environmental Sciences, Department of Chemistry, Chemical Analysis & Mass Spectrometry Facility, University of New Orleans, New Orleans, LA 70148, USA.
| | - Phoebe Zito
- Pontchartrain Institute for Environmental Sciences, Department of Chemistry, Chemical Analysis & Mass Spectrometry Facility, University of New Orleans, New Orleans, LA 70148, USA
| | - Anne M Kellerman
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, USA; National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | | | | | - Donald F Smith
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
| | - Xiaoyan Cao
- Department of Chemistry, Brandeis University, Waltham, MA 02453, USA
| | | | - Sasha Wagner
- Department of Earth and Environmental Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA; Department of Chemistry and Chemical Biology, Department of Marine and Environmental Sciences, Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, USA
| | - Aron Stubbins
- Department of Chemistry and Chemical Biology, Department of Marine and Environmental Sciences, Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, USA
| | - Robert G M Spencer
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL, USA; National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
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García-Rincón J, Gatsios E, Rayner JL, McLaughlan RG, Davis GB. Laser-induced fluorescence logging as a high-resolution characterisation tool to assess LNAPL mobility. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 725:138480. [PMID: 32298881 DOI: 10.1016/j.scitotenv.2020.138480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/16/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
High-resolution characterisation tools such as Laser-Induced Fluorescence (LIF) logging represent a step forward towards a more effective management of sites contaminated by light non-aqueous phase liquid (LNAPL) petroleum hydrocarbons. In this paper, the applicability of LIF response as an indicator of LNAPL mobility at one site with an unconsolidated aquifer was investigated. LIF profiles were logged adjacent to twin coring locations and wells with LNAPL transmissivity (Tn) measurements in a heterogeneous gasoline contaminated site in Western Australia. LIF response was correlated to Tn to a greater extent than LNAPL saturation (Sn) measurements from coring. In particular, LIF signal maxima were a better indicator of Tn than the integral LIF signal. Furthermore, LIF allowed rapid identification of areas with long-term near-immobile LNAPL (entrapped and residual) because of the multi-wavelength waveforms associated with distinct subsurface characteristics. It was also demonstrated that the delineation of presumably less-mobile intervals could be enhanced by using the relative LIF response in the 350 nm wavelength channel. Thus, this work gave evidence that LIF logging provides valuable information about LNAPL distribution and mobility in commonly found subsurface settings, despite generally poor correlations with Sn measurements. LIF probes can be successfully used to guide the installation and application of more costly conventional methods in addition to the development of existing site models.
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Affiliation(s)
- Jonás García-Rincón
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; Faculty of Engineering and Information Technology, University of Technology Sydney, 15 Broadway, Ultimo, NSW 2007, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Australia.
| | - Evangelos Gatsios
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; Faculty of Engineering and Information Technology, University of Technology Sydney, 15 Broadway, Ultimo, NSW 2007, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Australia.
| | - John L Rayner
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Australia.
| | - Robert G McLaughlan
- Faculty of Engineering and Information Technology, University of Technology Sydney, 15 Broadway, Ultimo, NSW 2007, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Australia.
| | - Greg B Davis
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Australia; School of Earth and Environment, University of Western Australia, Nedlands, WA, Australia.
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Sookhak Lari K, Davis GB, Rayner JL, Bastow TP, Puzon GJ. Natural source zone depletion of LNAPL: A critical review supporting modelling approaches. WATER RESEARCH 2019; 157:630-646. [PMID: 31004979 DOI: 10.1016/j.watres.2019.04.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 03/23/2019] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) includes partitioning, transport and degradation of LNAPL components. NSZD is being considered as a site closure option during later stages of active remediation of LNAPL contaminated sites, and where LNAPL mass removal is limiting. To ensure NSZD meets compliance criteria and to design enhanced NSZD actions if required, residual risks posed by LNAPL and its long term behaviour require estimation. Prediction of long-term NSZD trends requires linking physicochemical partitioning and transport processes with bioprocesses at multiple scales within a modelling framework. Here we expand and build on the knowledge base of a recent review of NSZD, to establish the key processes and understanding required to model NSZD long term. We describe key challenges to our understanding, inclusive of the dominance of methanogenic or aerobic biodegradation processes, the potentially changeability of rates due to the weathering profile of LNAPL product types and ages, and linkages to underlying bioprocesses. We critically discuss different scales in subsurface simulation and modelling of NSZD. Focusing on processes at Darcy scale, 36 models addressing processes of importance to NSZD are investigated. We investigate the capabilities of models to accommodate more than 20 subsurface transport and transformation phenomena and present comparisons in several tables. We discuss the applicability of each group of models for specific site conditions.
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Affiliation(s)
- Kaveh Sookhak Lari
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA, 6913, Australia; School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA, 6027, Australia.
| | - Greg B Davis
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA, 6913, Australia; School of Earth Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - John L Rayner
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA, 6913, Australia
| | - Trevor P Bastow
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA, 6913, Australia
| | - Geoffrey J Puzon
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA, 6913, Australia
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