title: A risk-based approach for identifying constituents of concern in oil sands process-affected water from the Athabasca Oil Sands region.
abstract: Mining leases in the Athabasca Oil Sands (AOS) region produce large volumes of oil sands process-affected water (OSPW) containing constituents that limit beneficial uses and discharge into receiving systems. The aim of this research is to identify constituents of concern (COCs) in OSPW sourced from an active settling basin with the goal of providing a sound rational for developing mitigation strategies for using constructed treatment wetlands for COCs contained in OSPW. COCs were identified through several lines of evidence: 1) chemical and physical characterization of OSPW and comparisons with numeric water quality guidelines and toxicity endpoints, 2) measuring toxicity of OSPW using a taxonomic range of sentinel organisms (i.e. fish, aquatic invertebrates, and a macrophyte), 3) conducting process-based manipulations (PBMs) of OSPW to alter toxicity and inform treatment processes, and 4) discerning potential treatment pathways to mitigate ecological risks of OSPW based on identification of COCs, toxicological analyses, and PBM results. COCs identified in OSPW included organics (naphthenic acids [NAs], oil and grease [O/G]), metals/metalloids, and suspended solids. In terms of species sensitivities to undiluted OSPW, fish ≥ aquatic invertebrates > macrophytes. Bench-scale manipulations of the organic fractions of OSPW via PBMs (i.e. H2O2+UV254and granular activated charcoal treatments) eliminated toxicity to Ceriodaphnia dubia (7-8 d), in terms of mortality and reproduction. Results from this study provide critical information to inform mitigation strategies using passive or semi-passive treatment processes (e.g., constructed treatment wetlands) to mitigate ecological risks of OSPW to aquatic organisms.
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA. Electronic address: andrew.d.mcqueen@gmail.com.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: McQueen
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: Ciera M
authors.initials: CM
authors.lastname: Kinley
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: Maas
authors.initials: M
authors.lastname: Hendrikse
authors.affiliation: Department of Environmental Engineering & Earth Sciences, 445 Brackett Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Gaspari
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: Alyssa J
authors.initials: AJ
authors.lastname: Calomeni
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: Kyla J
authors.initials: KJ
authors.lastname: Iwinski
authors.affiliation: Department of Environmental Engineering & Earth Sciences, 445 Brackett Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: James W
authors.initials: JW
authors.lastname: Castle
authors.affiliation: Contango Strategies Limited, LFK Biotechnology Complex, 15-410 Downey Road, Saskatoon, SK S7N 4N1, Canada.
authors.forename: Monique C
authors.initials: MC
authors.lastname: Haakensen
authors.affiliation: Water Science and Technology Directorate, Environment and Climate Change Canada, 11 Innovation Blvd, Saskatoon, SK S7N 3H5, Canada.
authors.forename: Kerry M
authors.initials: KM
authors.lastname: Peru
authors.affiliation: Water Science and Technology Directorate, Environment and Climate Change Canada, 11 Innovation Blvd, Saskatoon, SK S7N 3H5, Canada.
authors.forename: John V
authors.initials: JV
authors.lastname: Headley
authors.affiliation: Department of Forestry and Environmental Conservation, 261 Lehotsky Hall, Clemson University, Clemson, SC 29634, USA.
authors.forename: John H
authors.initials: JH
authors.lastname: Rodgers
mesh_terms: D000818:Animals; D002264:Carboxylic Acids / Q000032:analysis; D002606:Charcoal / Q000032:analysis; D033361:Cladocera / Q000187:drug effects*; D006838:Hydrocarbons / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis; D008906:Mining; D061329:Oil and Gas Fields / Q000737:chemistry*; D018675:Toxicity Tests / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
chemical_list: D002264:Carboxylic Acids; D006838:Hydrocarbons; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical; D002606:Charcoal; D006861:Hydrogen Peroxide; C046170:naphthenic acid
keywords: External tailings facility; Fish; Naphthenic acids; Oil sands process-affected water; Toxicity