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Oil Sands Environmental Management Bibliography

The Cumulative Environmental Management Association (CEMA)partnered with the Oil Sands Research and Information Network (OSRIN) to create the new Oil Sands Environmental Management Bibliography, which includes documents relevant to the environmental management of oil sands development in Alberta. The majority of the documents focus on the mineable oil sands in the Athabasca deposit, though some documents relate to in-situ developments. This bibliography was last updated in November 2014.

Effect of ozonation on the estrogenicity and androgenicity of oil sands process-affected water

Year of Publication: 2011

Abstract:
There is increasing environmental concern about the volume of oil sands process-affected water (OSPW) produced by the oil sands industry in Alberta, Canada. There is limited knowledge of the toxic effects of OSPW and one of the primary organic constituents, naphthenic acids (NAs), which are thought to be one of the toxic constituents of OSPW. OSPW and NAs can have endocrine disrupting potential. The NAs in OSPW are persistent, but ozonation can significantly reduce concentrations of NA, while increasing their biodegradability, and consequently reduce OSPW toxicity. However, it is of concern that OSPW ozonation might generate hydroxylated cycloaliphatics with endocrine disrupting potential. In this study, the estrogen receptor- (ER) and androgen receptor- (AR) mediated effects of OSPW and ozone-treated OSPW were investigated in vitro by use of T47D-kbluc (estrogen responsive) and MDA-kb2 (androgen responsive) cells. Ozonation neither attenuated nor intensified the estrogenicity of OSPW. The estrogenic responses to untreated OSPW and ozone treated OSPW were 2.58(±0.22)-fold and 2.48(±0.13)-fold greater than those of controls, respectively. Exposure to untreated OSPW produced significant antiandrogenicity in the presence of 0.01, 0.05, or 0.1 nM testosterone (T), while ozone-treated OSPW produced significant antiandrogenicity in the presence of 0.01 or 0.05 nM T. Exposure to untreated and ozone-treated OSPW also caused potentiation of androgen receptor-mediated effects of T. OSPW could cause estrogenic and antiandrogenic effects through receptor mediated pathways, and ozonation can partially mitigate the OSPW antiandrogenicity as well as androgen potentiating effect, without increasing estrogen potency.

Effect of ozonation on the naphthenic acids' speciation and toxicity of pH-dependent organic extracts of oil sands process-affected water

Year of Publication: 2015

Abstract:
The presence of naphthenic acids (NAs) and other organic constituents in oil sands process-affected water (OSPW) stored in tailings ponds, poses a serious environmental threat due to their potential toxicity to aquatic organisms and wild life. In this work, four fractions of OSPW, extracted by dichloromethane at different pHs, were ozonated to determine the ozone impact on NAs degradation. Extracts distributions showed that high carbon number NAs (14–22) were associated with higher pH fractions (pH > 7) and smaller carbon number NAs (7–13) with lower pH fractions (pH ≤ 7). Extracts showed similar hydrogen deficiency (Z-number) patterns centered on Z = 6. Analysis of the speciation of NAs and oxidized NAs in the four fractions showed that ozonation degraded most NAs (55% to 98%). Despite the high degradation levels, there was still significant toxicity of the fractions toward goldfish macrophages and measurable toxicity toward Vibrio fischeri. The toxicity of such a complex matrix as OSPW may be attributed to other organic compounds and degradation by-products not currently detected. Thus, there is a need to elucidate which compounds are responsible for the remaining OSPW toxicity and to determine if combined processes, such as ozonation followed by biological treatment, are able to completely detoxify OSPW. This work is taking the first steps into this direction, narrowing down the range of compounds which might be responsible for the toxicity.

Effect of pH on neutral lipid and biomass accumulation in microalgal strains native to the Canadian prairies and the Athabasca oil sands

Year of Publication: 2013

Abstract:
Algal biodiesel has been a subject of growing importance in the realm of renewable energy due to carbon capture properties and its potential for photosynthetic efficiency with high lipid output. This study identified five isolates of freshwater green algae, belonging to the Chlorellaceae, and measured the lipid classes and fatty acid profiles of these species to determine suitability for biodiesel production. To induce the greater accumulation of lipids, especially in the form of triacylglycerols (TAGs) desired for biodiesel, we examined the lipid accumulation in cells stressed by nitrogen limitation, sulfur deficiency, or pH stress. Increases in biomass were monitored in order to determine if adjusting pH incrementally over the course of the experiment had any effect on growth and lipid accumulation of several isolates. TAG accumulation was visually screened by Nile Red fluorescence and further assessed by gas chromatography. Lipid amounts were comparably equal or better for pH stress treatments than for standard nutrient-deprivation treatments. Incrementally adjusted pH over the course of growth triggered lipid accumulation comparable to constant pH stress treatments, yet biomass accumulation was equivalent to unstressed growth. One isolate obtained from the Athabasca oil-sands region of Alberta, OS4-2, is a good candidate for biodiesel production, having accumulated over 45 % of its dry weight as lipid, with over 80 % of the lipid as triacylglycerols, and contains an abundance of 18:1 fatty acids. This class of fatty acids improves the cold flow and oxidative stability of biodiesel and is ideal for biofuel used in a Canadian climate.

Effect of reactor configuration and microbial characteristics on biofilm reactors for oil sands process-affected water treatment

Year of Publication: 2014

Abstract:
Batch and continuous biofilm reactors (BBR and CBR) were operated to treat raw and ozone-treated oil sands process-affected water (OSPW). In raw OSPW, the BBR removed less (24% vs. 29%) chemical oxygen demand (COD) than did the CBR. The CBR removed 14% of the acid-extractable fraction (AEF) from raw OSPW and 51% from ozonated OSPW, whereas the BBR had lower AEF removal efficiencies of 6.2% and 37% for raw and ozonated OSPW, respectively. NAs with low molecular weight were preferentially degraded over those with high molecular weight, and classical NA degradation was more effective in the CBR than in the BBR. CBR operation with ozone-treated OSPW allowed a favorable growth of bacteria due to the high bioavailability of low molecular weight compounds. Scanning electron micrographs showed that distinct biofilm and extracellular polymeric substances (EPS) were formed under continuous flow conditions, and that the biofilm was thicker in the CBR than in the BBR. Microbial community analysis using denaturing gradient gel electrophoresis (DGGE) revealed more bands in BBR biomass samples; 23 strains were identified in the BBR compared to 21 in the CBR. The continuous flow mode removed organic compounds more favorably than the batch mode from raw and ozonated OSPW.

Effect of residual bitumen on polymer-assisted flocculation of fluid fine tailings

Authors Klein, C. C. G.
Year of Publication: 2014

Abstract:
In bitumen recovery from oil sands, a percentage of the bitumen is lost to tailings. The effect of fugitive bitumen on fines settling and consolidation in tailings ponds remains controversial. In the current study, the settling performance of mature fine tailings (MFT) in response to flocculant addition was considered by studying MFT of varying bitumen content. Bitumen content in the MFT was adjusted by controlled removal of bitumen using a Denver flotation cell. The initial settling rate of flocculated MFT was observed to increase with decreasing bitumen content from 0.45 to 0.18 wt%. A further reduction in bitumen content was found to dramatically decrease the settling rate of flocculated MFT. Such behaviour seems counterintuitive since the polymer flocculant was found to have a low affinity for bitumen contaminated surfaces, as measured by quartz crystal microbalance with dissipation (QCM‐D), which would predict a further increase in settling rate of flocculated MFT with decreasing bitumen content. Reasons for this behavior were investigated and it was observed that the decrease in settling rate coincided with long periods of intense mixing in the Denver cell. The underlying reason for this behavior is the subject of ongoing investigation. The current study confirms the use of flotation as a viable option to control MFT bitumen content and improve the settling rate of flocculated MFT

Effect of salt on the flocculation behavior of nano particles in oil sands fine tailings

Year of Publication: 1996

Abstract:
Currently, two commercial plants, operating in the Athabasca region of Alberta, produce approximately 20 percent of Canada's petroleum requirements from oil sands. Surface mined oil sand is treated in a water based separation process that yields large volumes of clay tailings with poor settling and compaction characteristics. Clay particles, suspended in the pond water, interact with salts, dissolved from the oil sands ore, to produce mature fine tailings (MFT) containing only 20 to 50 w/w% solids. As a result, large sedimentation ponds are required to produce enough process water to recycle for the plant. Tailings pond dykes can only be constructed during a short summer season. Consequently, the capability to predict production rate and final volume of MFT is essential for mine planning and tailings disposal operations. Previous research has demonstrated that a small fraction of nano sized clay particles (20 to 300 nm) effectively controls the bulk properties of MFT. These particles are present in the original ore and become mobilized into the water phase during the oil separation process. In this work, the nano sized particles have been separated from the bulk tailings and subjected to a fundamental study of their flocculation behavior in model tailings water. Photon correlation spectroscopy and a deuterium NMR method were used to follow particle flocculation and gelation processes. These results were correlated with particle settling data measured under the same conditions. It was determined that the nano particles form fractal flocs that eventually interact to give a thixotropic gel. The ultimate sediment volume produced is almost entirely dependent on the original concentration of nano particles while the rate of water release is governed primarily by electrolyte con- centration.

Effect of sulfur dioxide on woody boreal forest species grown on native soils and tailings

Year of Publication: 1984

Abstract:
A study was carried out on the influence of 15.2 µmol m–3 (0.34 ppm) (Canadian maximum acceptable limit) of SO2 on net CO2 assimilation rate (NAR) and visible symptom development of several boreal forest woody species. Fumigation with SO2 significantly reduced NAR in all species and produced visible symptoms of injury in 2 to 20 d. The decrease in NAR of deciduous species {aspen (Populus tremuloides Michx.), willow (Salix sp.), green alder [Alnus crispa (Ait.) Parsh], and paper birch (Betula papyrifera Marsh)} was significantly more rapid than of conifers { jack pine (Pinus banksiana Lamb.), white spruce [Picea glauca (Moench) Voss], and black spruce [P. mariana (Mill.) BSP]} or an evergreen angiosperm [Labrador tea (Ledum groenlandicum Oeder)] when grown on a fertilized Brunisol. cases did not appear until NAR had decreased considerably. The response of these metabolic and visible responses appeared to be related to differences in S uptake owing in part to higher gas exchange rates for deciduous species than for conifers. Conifers growing in oil sands tailings responded to SO2 with a significantly more rapid decrease in NAR as compared with those growing in the Brunisol. Because both soils were fertilized, nutrient status was ruled out as a cause. It is suggested that the conifers obtained from the railings dike were predisposed to SO2 fumigation by either the presence of toxic material in the tailings sand or their history of exposure to moderate levels of SO2. Sulfur uptake and visible symptom development were not different on tailings as compared with the Brunisol.

Effective project management of oil & gas projects: A model for oil sands' SAGD plants

Authors Halari, A. A.
Year of Publication: 2011

Abstract:
With its vast oil reserves, Alberta is poised to become one of the world’s major oil suppliers. However, extracting this oil economically will require effective management of the oil sands’ projects in order to build them on time and within budget. Projects are subject to both internal and external forces such as political, economic, social and technological which can destabilize and create tremors to the execution. The SAGD-ET model developed in this research, with its three pillars of engineering, project management processes and communications, provides valuable solutions to these types of issues thus encouraging effective project execution. This model was developed using the Delphi Method of survey by collecting lessons learned from professionals in the oil & gas industry who had worked on SAGD projects. The lessons learned which were then rated allowed for the identification of critical areas for successful execution of SAGD projects. The SAGD-ET model also provides solutions to the problems encountered during the engineering, procurement and construction phases of SAGD and oil & gas projects.

Effectiveness of above-ground pipeline mitigation for moose (Alces alces) and other large mammals

Year of Publication: 2009

Abstract:
Above-ground pipelines for in situ oil sands development are potentially significant vectors of habitat fragmentation for large mammals. We evaluated the use of elevated pipeline clearances (distance between the ground and the bottom of the pipeline) and pipeline crossing structures, the two primary methods of mitigating the barrier effect of above-ground pipelines on large mammals, with a particular emphasis on moose (Alces alces), in northern Alberta, Canada. Winter snow tracking and remote cameras were employed for one year to monitor large mammal interactions with a 5.5km stretch of pipeline mitigated with five pipeline crossing structures and a 1.6km control area of unmitigated pipeline. A minimum threshold pipeline clearance of 140cm was critical in allowing adult moose to cross underneath the pipeline. Pipeline crossing structures facilitated movement across the pipeline and were used more than sections of elevated pipelines by all species.

Effectiveness of ozonation treatment in eliminating toxicity of oil sands process-affected water to Chironomus dilutus

Year of Publication: 2011

Abstract:
Water soluble organic compounds (OCs), including naphthenic acids (NAs), are potentially toxic constituents of oil sands process-affected water (OSPW) that is generated during extraction of bitumen from Alberta oil sands. Ozonation can decrease concentrations of OCs in OSPW. However, effects of ozonated-OSPW on multicellular organisms are unknown. A 10-day and a chronic exposure of Chironomus dilutus to OSPW were conducted to assess effects on survival, growth, development, and behavior. Two separate batches of OSPW were treated with 30 or 80 mg ozone (O(3))/L. Wet body masses of larvae exposed to OSPW were 64 to 77% less than their respective controls (p < 0.001). However, both levels of ozonation significantly attenuated effects of OSPW on growth. Similarly, chronic exposure to untreated OSPW resulted in significantly less pupation than in the controls, with 31% and 71% less pupation of larvae exposed to the two batches of OSPW (p < 0.05). Emergence was significantly less for larvae exposed to OSPW, with 13% and 8% of larvae emerging, compared to 81% in controls (p < 0.0001). Both levels of ozonation of OSPW attenuated effects on emergence. These results suggest that OCs degraded by ozonation causes toxicity of OSPW toward C. dilutus, and that ozonation attenuates toxicity of OSPW.

Effectiveness of soil N availability indices in predicting site productivity in the oil sands region of Alberta

Year of Publication: 2012

Abstract:
Quantitative relationships between soil N availability indices and tree growth are lacking in the oil sands region of Alberta and this can hinder the development of guidelines for the reclamation of the disturbed landscape after oil sands extraction. The aim of this paper was to establish quantitative relationships between soil N availability indices and tree growth in the oil sands region of Alberta. In situ N mineralization rates, in situ N availability measured in the field using Plant Root Simulators (PRS™ probes), laboratory aerobic and anaerobic soil N mineralization rates, and soil C/N and N content were determined for both the forest floor and the 0-20 cm mineral soil in eight jack pine (Pinus banksiana Lamb.) stands in the oil sands region in northern Alberta. Tree growth rates were determined based on changes in tree ring width in the last 6 years and as mean annual aboveground biomass increment. Soil N availability indices across those forest stands varied and for each stand it was several times higher in the forest floor than in the mineral soil. The in situ and laboratory aerobic and anaerobic soil N mineralization rates, soil mineralized N, in situ N availability measured using PRS probes, soil C/N ratio and N content in both the forest floor and mineral soil, as well as stand age were linearly correlated with tree ring width of jack pine trees across the selected forest stands, consistent with patterns seen in other published studies and suggesting that N availability could be a limiting factor in the range of jack pine stands studied. In situ and laboratory aerobic and anaerobic N mineralization rates and soil C/N ratio and N content can be used for predicting tree growth in jack pine forests in the oil sand region. Laboratory based measurements such as aerobic and anaerobic N mineralization rates and soil C/N ratio and N content would be preferable as they are more cost effective and equally effective for predicting jack pine growth.

Effectiveness of three waterfowl deterrents on natural and polluted ponds

Authors Boag, D. A., & Lewin V.
Year of Publication: 1980

Abstract:
In 1975, 3 types of waterfowl deterrent (a model falcon, a moving series of reflectors suspended from a frame, and a human effigy) mounted on floats, were tested for efficacy in deterring waterfowl from entering a series of small natural ponds in the boreal forest of Alberta. Only the effigy appeared to be effective; diving ducks of the genus Aythya were affected most. In 1976, the human effigy was tested on an artificial tailings pond that received aqueous and bituminous effluent from an oil sands extraction plant near Fort McMurray, Alberta. Twenty-seven effigies were deployed over the 150-ha pond. Their effectiveness was judged by comparing the number of waterfowl dying in and associated with this pond in 1975 (without deterrents) with number dying in and associated with it in 1976 (with deterrents). Kill figures in 1976 were significantly lower than expected on the basis of relative abundance of birds in the 2 years. We concluded that this decline was due to the presence of the effigies.

Effects of air pollutants on the forest ecosystem: A review

Authors Cabral, E.
Year of Publication: 1986

Abstract:
Air pollution and its effects on various ecosystems has been a subject of increasing controversy. The European forest damage situation has heightened the public's awareness of the problem. Historically, the observed pollution damage was believed to be due mainly to sulphur dioxide pollution. Recent research has indicated that other factors including nitrogen oxides, ozone and other photo-oxidants, and various climatic conditions contribute to the problem. The possibility of a multiple-pollutant effect is recognized and is leading to a more multi-disciplinary approach to the study of the effects of air pollution on forest ecosystems. In Canada, research has centred around the higher emission areas in the eastern part of the country. In the western provinces, there is a concern that the forests may be adversely affected in the long term. Alberta is in a fortunate situation because most of its soils are underlain by calcareous bedrock and can, therefore, neutralize in-coming acids more efficiently than areas covered by the Canadian Shield. However, sensitive areas do exist, and the long-term impact of continuous inputs into the system is not yet fully understood.

Effects of alkyl chain branching on the biotransformation of naphthenic acids

Year of Publication: 2008

Abstract:
The rapid expansion of the oil sands industry has seen a concomitant expansion of the production of associated waste containing toxic naphthenic acids (NAs). Bioremediation of such waste is thus an important goal, but the mechanisms of biodegradation are still poorly understood, despite recent advances. Many oil sands NAs are resistant to biodegradation, and alkyl side chain branching has been invoked as an explanation. To investigate this hypothesis we examined the biotransformation by a sedimentary bacterial community of novel, synthetic, surrogate NAs (butylcyclohexylbutanoic acids (BCHBAs)) with variously branched butyl side chains (n- through t-) and unbranched alkanoate groups, plus one (4-(4'-isobutylcyclohexyl)pentanoic acid (iso-BCHPA)), with both branched butyl and branched alkanoate chains. Sediment microbial populations were inoculated into media containing the individual surrogate NAs, and gas chromatography-mass spectrometry (GC-MS) was used to determine the extent of biotransformation. Biotransformation decreased as NA side chain branching increased. For example, over 97% of the n-BCHBA with the nonbranched alkyl side chain was transformed in 30 days compared to the tert-BCHBA with the most highly branched side chain where only 2.5% was transformed. Both the iso-BCHBA and sec-BCHBA had intermediate transformation rates with about 77% and 47% transformed respectively after 30 days. The metabolites were identified as butylcyclohexylethanoic acids in each case, indicating beta-oxidation of the alkanoate substituents. The iso-BCHPA with both chains branched was resistant to degradation. The results are thus consistent with earlier hypotheses for the resistance of oil sands NAs. Identification of bacteria capable of oxidizing such branched alkyl chains-or of attacking the cyclic rings of NAs, may be important if bioremediation of oil sands NAs is to be achieved.

Effects of an industrial effluent on plant colonization and on the germination and post-germinative growth of seeds of terrestrial and aquatic plant species

Year of Publication: 2002

Abstract:
Major oil sands industrial companies are located in the Athabasca Oil Sands Deposit in northeastern Alberta, Canada. During the process used to extract light crude oil (via hot water digestion and flotation), gypsum is usually added to produce consolidated tails (CT) and CT release water. The vast volumes of process-treated waters (effluent) are held within large dyked tailings ponds. Toward testing viable options for reclamation, various hummock–wetlands systems have been constructed; in addition, natural wetlands (inhabited by obligate wetland plant species) have become established as a result of seeping of the effluents held within the large dyked ponds. Vegetation surveys conducted on and around the industrial site revealed that the constructed wetlands asso- ciated with the dyke drainage (effluent treated with phosphorous) and consolidated tails (CT; effluent treated with gypsum) had low biodiversity and were not invaded by many aquatic plants. Although the natural wetland was also not invaded by many aquatic species, it was found to be as diverse as the reference wetlands (i.e. off-site wetlands not exposed to the effluents). Exposure to oil sands effluents had an inhibitory effect on the germination (percent and/or rate) of several plant species (tomato, clover, wheat, rye, pea, reed canary grass, loblolly pine); clover and tomato seed germination were most affected. Two treatments in particular (efflu- ents from the natural on-site wetland and the CT constructed wetland), delayed germination, and also led to reduced fresh weight of seedlings of tomato, wheat, clover and loblolly pine. The osmolarities of the effluents associated with the natural on-site wetland and CT constructed wetland were 712 and 728 mOs/kg, respectively; substituting these effluents with solutions of polyethylene glycol of the same osmotic potentials had a greater inhibitory effect on germination rate. The negative effects of the effluents on seed germination may account for the paucity of aquatic species that invaded the oil sands impacted wetlands. This factor will also be critical in determining the long-term feasibility of hummock–wetland systems.

Effects of canopy-deposition interaction on H+ supply to soils in Pinus banksiana and Populus tremuloides ecosystems in the Athabasca oil sands region in Alberta, Canada

Year of Publication: 2011

Abstract:
Soil acidification has been of concern in the oil sands region in Alberta due to increased acid deposition. Using the canopy budget model, and accounting for H+ canopy leaching by organic acids, we determined sources and sinks of H+ in throughfall in jack pine (Pinus banksiana) and trembling aspen (Populus tremuloides) stands in two watersheds from 2006 to 2009. In pine stands, H+ deposition was greater in throughfall than in bulk precipitation while the opposite was true in aspen stands. The annual H+ interception deposition was 148.8–193.8 and 49.7–70.0 molc ha−1 in pine and aspen stands, respectively; while the annual H+ canopy leaching was 127.1–128.7 and 0.0–6.0 molc ha−1, respectively. The greater H+ supply in pine stands was caused by greater interception deposition of SO42− and organic acids released from the pine canopy. Such findings have significant implications for establishing critical loads for various ecosystems in the oil sands region.

Effects of contaminants on aquatic organisms in the Peace, Athabasca and Slave river basins

Year of Publication: 1996

Abstract:
This report summarizes the activities of the Contaminants Component of the Northern River Basins Study to address the following questions: How the aquatic ecosystems in the Peace, Athabasca, and Slave River basins been affected by exposure to toxic compounds; and what long-term monitoring programs and predictive models are required to provide ongoing assessment of the state of those ecosystems. Research is described in four project areas: A basin-wide survey of biochemical responses to organochlorines and other contaminants in major fish species; a basin-wide survey of the toxicity in bottom and suspended sediments; an assessment of the utility of semi-permeable membrane devices as potential substitutes for wild fish in a long-term monitoring program; and assessment of the feasibility of using small, locally resident fish species as alternates to large adult fish in a long-term biological effects monitoring program.

Effects of diluted bitumen on crude oil transmission lines

Authors
Year of Publication: 2013

Abstract:
TRB Special Report 311: Effects of Diluted Bitumen on Crude Oil Transmission Pipelines analyzes whether shipments of diluted bitumen have a greater likelihood of release from pipelines than shipments of other crude oils. The oil sands region of Canada is the source of diluted bitumen shipped by pipeline to the United States. The committee that produced the report did not find any pipeline failures unique to the transportation of diluted bitumen or evidence of physical or chemical properties of diluted bitumen shipments that are outside the range of those of other crude oil shipments. The committee's comprehensive review did not find evidence of any specific aspect of the transportation of diluted bitumen that would make it more likely than other crude oils to cause pipeline releases.

Effects of eroding oil sand and periodic flooding on benthic macroinvertebrate communities in a brown-water stream in northeastern Alberta Canada

Year of Publication: 1979

Abstract:
The portion of the Steepbank River which cuts through the Athabasca oil sands deposit supported a less diverse benthic invertebrate community than did upstream areas. The variety and relative abundance of Plecoptera and Trichoptera were consistently lower in the area of oil sand exposure. As a substrate for benthic invertebrates, oil sand appears to be analogous to bedrock, supporting about 60% as many animals per unit area as adjacent rubble substrates. Burrowingand negatively phototropicorganisms were significantly less abundant on oil sand than on rubble. When high discharge of the Athabasca River flooded a riffle to form a pool near the mouth of the Steepbank, rheophilic forms, such as Barfis and Sin~uliutnw, e!-e largely eliminated from the rime and benthic standing stocks were reduced by about 50%. The invertebrate community recovered quickly after rifRe conditions returned.

Effects of exposure to naphthenic acids in tree swallows (Tachycineta bicolor) on the Athabasca oil sands, Alberta, Canada

Year of Publication: 2007

Abstract:
Naphthenic acids (NAs) are a group of carboxylic acids that are of particular concern to the steadily growing oil sands mining industry of Alberta, Canada, because they become highly concentrated in the water used for oil sands extraction and are toxic to aquatic biota and mammals. Upon mine closure, vast amounts of process-affected water will need to be reclaimed and proven safe for wildlife colonizing reclaimed areas. The effects of exposure to NAs have not been investigated in avian species. To address this void, tree swallow (Tachycineta bicolor) nestlings were dosed with NAs while being reared normally by their free-ranging parents on a site in the vicinity of the oil sands. Nestlings received 1.5 mg NAs/day (approximately 0.075 g/kg body mass) from d 7 to d 13 of age, which represented a 10-fold “worst exposure” scenario. Nestling growth, hematocrit, blood biochemistry, organ weights, and ethoxyresorufin O-deethylase (EROD) activity were unaffected by NAs. The only change detected on histopathological evaluation of major organs was an increase in extramedullary erythropoiesis in the liver. These findings indicate that nestling tree swallows can successfully tolerate short-term exposures to environmentally realistic concentrations of NAs. However, this study did not investigate the chronic or reproductive toxicity of NAs. More research needs to be conducted to complete this initial assessment, to determine environmental risks on reclaimed areas where birds will be breeding and where their exposure to NAs could extend for several weeks.

Effects of exposure to oil sands process-affected water from experimental reclamation ponds on Chironomus dilutus

Year of Publication: 2012

Abstract:
Effective detoxification of oil sands process-affected water (OSPW) is one issue associated with bitumen extraction in the Alberta oil sands. It has been suggested that reclamation ponds can be used to passively treat OSPW, potentially allowing for its safe return to the environment. In this study, OSPW was sampled in two batches (A and B) from the Syncrude Canada Ltd. West In-Pit (WIP) settling pond and from three experimental reclamation ponds – Big Pit, FE5, and TPW. Acute (10 d) and chronic (until adult emergence) exposures of Chironomus dilutus larvae to OSPW were conducted and survival, growth, development, and behavior were assessed. Masses of larvae exposed to WIP-OSPW were 64–77% less than the freshwater control (p < 0.001). Similarly, chronic exposure to WIP-OSPW resulted in significantly (p < 0.05) less pupation than in the freshwater control, with 31% (A) and 71% (B) less pupation of larvae exposed to WIP-OSPW. Rates of emergence were significantly less for larvae exposed to WIP-OSPW, with only 13% (A) and 8% (B) of larvae emerging as adults when exposed to WIP-OSPW, compared to 81% in the freshwater control (p < 0.0001). Pupation and emergence rates were significantly less in TPW than freshwater control (p < 0.05), but there were no differences observed in Big Pit or FE5. Lesser toxicity was observed in reclaimed OSPW compared to fresh OSPW and this coincided with lesser concentrations of NAs. The results presented are consistent with the hypothesis that an organic fraction is the cause of the toxicity of OSPW toward C. dilutus and that OSPW aged in reclamation ponds retains toxicity and therefore, more aggressive, targeted treatment of OSPW is required to accelerate decreases.

Effects of hypoxia on ion accumulation in wild raspberry (Rubus idaeus) exposed to water released from saline oil sands mine tailings

Year of Publication: 2004

Abstract:
Composite tailings (CT) technology allows Alberta’s oil sands industry to reduce its volume of extraction tailings and accelerate the process of reclamation and revegetation of affected sites. Wild raspberry (Rubus idaeus) is desired on reclaimed sites; however, its sensitivity to ions in CT complicates its successful establishment. Hypoxia is another challenge for plants in CT, and is known to affect plant salt resistance. This study examined responses of raspberry exposed to CT release water under well-aerated and hypoxic conditions. Unlike many long-lived woody perennials that have been studied, raspberry did not accumulate Na and Cl in roots and therefore, the ability of roots to store these ions was not affected by the hypoxic conditions. This response suggests that the strategy of raspberry plants to cope with moderate salinity may be to protect roots, rather than shoots, against salt accumulation and possible salt injury. Contrary to Na, Cl, and S, well-aerated raspberry exhibited exclusion as a means of regulating B uptake by the roots. We suggest that the ability of roots to store salt should be used as an indicator of salt resistance in woody perennials designated for reclamation on saline sites.

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