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A preliminary evaluation of native psammophilous plants for revegetating oil sand tailings at Syncrude Canada (Fort McMurray Alberta)


Year: 1997

Abstract:
Native plants that naturally establish and thrive in sand (particularly on active dunes) are adapted to dry, nutrient deficient habitats and have evolved a tolerance to burial and exposure. In 1995, Wild Rose Consulting, Inc. and Syncrude Canada initiated a preliminary study to evaluate psammophilous plants (native to the local boreal ecoregion) for establishment and growth on oil sand tailings near Fort McMurray. Alberta. Seeds and roots of Astragalus aboriginum, Carex siccata, Deschampsia mackenzieana, Elymus mollis, Hierochloe odorata, Hudsonia tomentosa, Salix brachycarpa, and Stellaria arenicola were collected from three active dune sites in northern Alberta and Saskatchewan (Grande Prairie, Lesser Slave Lake, and Lake Athabasca). A preliminary survey of mycorrhizal symbionts was undertaken. Germination was tested after seeds were dried and cleaned. Species with adequate germination were tested for growth in tailing sands under controlled conditions. Astragalus aboriginum, Deschampsia mackenzieana, Salix brachycarpa, and Stellaria arenicola grew well in tailing sands in the greenhouse and were placed in field plots in 1996 (transplanted and seeded). Average survival of transplants in field plots was 80% or greater after two months in the first year. Deschampsia mackenzieana and Astragalus aboriginum seedlings were also emerging. Plants were divided into three groups based on their mycorrhizal symbionts: Elymus mollis, Deschampsia mackenzieana, and Hierochloe odorata formed vesicular-arbuscular mychorrizas, Hudsonia tomentosa and Salix brachycarpa were ectomycorrhizal, and Stellaria arenicola and Carex siccata lacked recognizable mycorrhizae.

Alberta oil sands: Supply security is just a pipeline away


Author(s): Herbst, A. M.

Year: 2004

Abstract:
We live in a world with a relentlessly growing demand for energy. Global geopolitical pressures and economics play important roles in the sourcing and development of energy and new strategic supplies. The availability of economical and secure supplies of energy, in particular crude oil, is especially important to the U.S. which consumes approximately 25% of the world's energy production. Ongoing instability in the Middle East has been a catalyst for the U.S. to seek crude oil supplies from sources closer to home such as Venezuela, Mexico and Canada. The Canadian oil sands industry, primarily located in the province of Alberta in western Canada, is one of the most secure sources of supply. Over the last few decades, Canadian oil sands production has grown from relatively modest test-well quantities to an amount approaching 1 million bpd. Oil sands are naturally occurring mixtures of several organic materials, mostly bitumen, water, sand and clay. A typical sample of oil sands contains approximately 12% bitumen by weight with a density greater than 960 kilograms per cubic meter, an API gravity of about 8 and a sulfur content of 4-6%. Alberta possesses three known large oil sands regions--Athabasca, Cold Lake, and Peace River. Advances in technology have made the production of bitumen (the hydrocarbon material found in oil sands) economically feasible and made it possible for these oil sands to be reclassified as proven reserves that measure 174.4 billion barrels. While these proven reserves are immense, their value is questionable if they cannot be developed and brought to market on a cost-effective basis.

An evaluation of the use of natural stable isotopes of water to track water movement through oil sands mine closure landforms


Author(s): Baer, T. J.

Year: 2014

Abstract:
Surface mining of oil sands results in extensive land disturbance, earth movement and water usage. After mining, the disturbed landscapes must be reconstructed and reclaimed as natural landforms. There are numerous challenges associated with understanding the responses of these landforms over time, including a need to track and characterize water movement through closure landforms to understand the hydrological responses of these landforms over time. This study attempted to use natural stable isotopes of water (δD and δ18O) to identify and characterize source waters from various closure landforms at an oil sands mine site. The study area is Syncrude‟s Mildred Lake mine, an open pit oil sands mine located in northern Alberta. A variety of groundwater, surface water and soil samples from a variety of landforms (overburden dumps, composite and mature fine tailings areas, tailings sand structures and freshwater reservoirs) were collected in an attempt to fully represent the isotopic distribution of waters across the mine site. Laboratory analysis of δD and δ18O was done on all samples. The local meteoric water line first established by Hilderman (2011) was redeveloped with additional precipitation data and calculated to be δD=7.0(δ18O) -18.6‰. A natural evaporation line having a slope of 5.3 was calculated for the mine site with samples collected from three surface water ponds on the mine site. Five primary source waters were identified on the mine site: process affected water/tailings, rainfall, snow, interstitial shale water and Mildred Lake water. It was found that these sources of water generally have unique natural stable water isotope signatures. Process affected water at the site generally had an enriched signature compared to other mine waters. The enrichment was attributed to fractionation from the recycle water circuit and natural evaporation. The characterizations of these source waters were then used in several hydrogeological examples to demonstrate that natural stable water isotopes can be applied to water balance estimates and to identify water movement processes related to closure landforms.

An examination of the toxic properties of water extracts in the vicinity of an oil sand extraction site


Year: 2011

Abstract:
The industrial extraction of oil sands (OS) in northern Alberta, Canada, has raised concerns about the quality of the Athabasca River. The purpose of this study was to examine the toxic properties of various water extracts on Oncorhynchus mykiss trout hepatocytes. The water samples were fractionated on a reverse-phase C(18) cartridge and the levels of light-, medium- and heavy-weight polycyclic aromatic hydrocarbons (PAHs) were determined by fluorescence spectroscopy. Primary cultures of trout hepatocytes were exposed for 48 h at 15 °C to increasing concentrations of the C(18) extract corresponding to 0.02, 0.1, 0.5 and 2.5X concentrations from upstream/downstream sites in the Athabasca River, lake and groundwater samples, OS tailings and interceptor well-water samples. Changes in cell viability, phase I and phase II biotransformation enzymes (cytochrome P4501A and glutathione S-transferase activities), oxidative damage (lipid peroxidation LPO) and genotoxicity (single and double DNA strand breaks) were monitored in post-exposure cells. The water samples decreased cell viability and increased all the above endpoints at thresholds of between 0.02 and 0.1X the water concentration. The most responsive biomarker was DNA damage but it also offered the least discrimination among sites. LPO was higher at sites downstream of the industrial operations compared to upstream sites. A decision tree analysis was performed to formulate a set of rules by which to identify the distinctive properties of each type of water samples. The analysis revealed that OS tailings and interceptor waters were characterized by an increased concentration in light PAHs (>42 μg L(-1)) and this fraction represented more than 85% of the total PAHs. These samples also inhibited GST activity, which could compromise the elimination of genotoxic PAHs present in the system. An analysis of groundwater samples revealed a contamination pattern similar to that for OS tailings. There is a need for more research into specific biomarkers of toxicity from OS tailings compounds such as naphthenic acids, light PAHs among others, which are a characteristic fingerprint of OS extraction activities.

An intensive surface water quality study of the Muskeg river watershed. Volume 1, Water chemistry


Author(s): Akena, A. M.

Year: 1979

Abstract:
This document is part of a series of research reports that describes the results of investigations funded under the Alberta Oil Sands Environmental Research Program, which was established by agreements of the Governments of Alberta and Canada in February 1975. This ten year program was designed to direct and co-ordinate research projects concerned with the environmental effects of development of the Athabasca Oil Sands in Alberta. This report documents and appraises baseline water chemical quality conditions of a lake and streams within the Muskeg River Watershed.

Arsenic source and distribution in groundwater from the Cold Lake oil sands region, Alberta


Year: 2014

Abstract:
Elevated arsenic concentrations have been observed in shallow groundwater in the Cold Lake Oil Sand Region of Alberta. The geology of this area includes up to 200 m of unconsolidated glacial deposits, with six regional interglacial sand and gravel aquifers, underlain by marine shale. Arsenic concentrations in unconsolidated sediment samples ranged between 1 to 17 ppm. Mineralogical characterization of the sediment samples revealed the presence of fresh framboidal pyrite in the deeper unweathered sediments with variable As contents of up to 1800 ppm. In contrast, the weathered sediments did not contain framboidal pyrite, but exhibited spheroidal Fe-oxyhydroxide grains with elevated As concentrations, interpreted as pseudomorphs after pyrite. X-ray absorption near edge spectroscopy (XANES) indicated that the weathered sediments are dominated by As5+ species having spectral features similar to those of goethite or ferrihydrite with adsorbed As, suggesting that Fe-oxyhydroxides are the dominant As carriers. XANES spectra collected from the unweathered sediment samples indicated the presence of a reduced As species characteristic of arsenopyrite and arsenian pyrite. A survey of over 800 water wells, isolated from industrial activity, were sampled for As and found that 50% of the wells contained As concentrations exceeding drinking water guidelines of 10 μg/L. Measurements of As speciation from 175 groundwater samples indicate that As(III) was the dominant species in 76% of the wells. Higher As concentrations in groundwater were associated with increasing depth and reducing conditions, circumneutral pH and lower concentrations of SO4. Speciation modelling showed that the majority of groundwater samples were undersaturated with respect to ferrihydrite, suggesting that reductive dissolution of Fe-oxyhydroxides, likely formed during glaciation, may be the source of some As in deeper groundwater whereas sulfide oxidation of pyrite during weathering is the source of As released to shallow aquifers. Understanding the distribution and form of As present naturally in the region’s aquifers is important for managing water resources to minimize the potential health risks of As exposure.

Assessment of a wet landscape option for disposal of fine tails from oil sands processing


Author(s): MacKinnon, M., & Boerger H.

Year: 1991

Abstract:
In the extraction of bitumen from oil sand using the Clark Hot Water Process, large volumes of a poorly consolidating fine tails are produced. This material will remain in suspension indefinitely and poses a problem for ultimate reclamation. Syncrude is examining various options for the disposal of this material. As part of an integrated approach, one method under evaluation is the storage of the fine tails sludge in the mined out pits and capping it with a layer of clean water. The capping layer will effectively isolate the fine tails from mixing and will sustain a viable aquatic ecosystem. Laboratory and field experimental results are presented to show the feasibility of this wei landscape option as an environmentally acceptable reclamation method for fine tails. Chemical and biological developments of the capping water are summarized and projections for the evolution of the resulting water body are given.

Athabasca Cold Lake and the future


Author(s): McFarland, J. D.

Year: 1990

Abstract:
It is suggested that Alberta oil sands have the potential to sustain and increase the wealth creation capacity of the Canadian petroleum sector now and well into the next century. Realizing this potential in the present-day competitive and interconnected world crude oil market is a challenge to be addressed in four areas: markets, operations, technology, and stakeholder support. Real price improvement in the world oil market is not expected in the near future, given near-static demand and a continuously increasing worldwide supply potential. Even in such a market, there are specialized niches where Canadian heavy oil should be competitive. These markets are continental and are mainly high- and medium-conversion refineries and upgraders. Demand for Canadian heavy oil is forecast to grow ca 4%/y to over 800,000 bbl/d by 2000. Supply will closely track demand 1995-98 and be slightly below demand before 1995 and after 1998. Improvements in existing operations to lower production costs and increase efficiency are being made at the Cold Lake and Syncrude facilities. The development of technology to improve recovery and lower supply costs will trigger further development, and impressive gains have already been realized as a result from ongoing research. The final condition needed to allow the oil sand sector to realize its potential is informed and supportive stakeholders (investors, customers, governments, and communities), who need to understand the unique attributes and potential awards of the oil sand business.

Athabasca oil sands multiple use corridor study: Corridor selection process


Year: 1986

Abstract:
In a region such as the Athabasca Oil Sands, a major consequence of resource development is the need to transport people, materials and energy into and out of the region. While resource development has encouraged the establishment or upgrading of transportation infrastructure such as roads, a railroad and an airport, linear facilities such as pipelines and power transmission lines are also required to serve the various resource activities during the construction and processing phases. To alleviate potential adverse effects placed upon the natural environment from the proliferation of linear facilities, the multiple use corridor concept has been accepted by the Department of Alberta Forestry, Lands and Wildlife, as a feasible remedy to such a situation. This study completes a preliminary step in the development of such a corridor in northeastern Alberta. The corridor proposed in this document will be adjusted and more clearly defined as additional studies, including the department's integrated resource planning process, are undertaken in the region. Furthermore, the process used by the planning team, to select the proposed corridor is described throughout Chapter 2. The study, when initiated, had been referred to as the Lac La Biche-McClelland Lake Multiple Use Corridor Study. However, the revised name Athabasca Oil Sands Multiple Use Corridor Study more accurately depicts the corridors' provincial location and the natural resource that it primarily will serve.

Athabasca River, Alberta


Year: 2001

Abstract:
The Athabasca is the longest and largest river in Alberta, and one of the few in Western North America unaltered by human impoundment. The River begins and ends at two of the most spectacular and significant natural features in the world. It rises in the Columbia Icefield, the hydrological apex of North America, and finally empties into Lake Athabasca and the 4100 square kilometre Peace-Athabasca Delta, one of the largest inland freshwater deltas in the world. The river was once a major shipping artery for goods into Canada's north and west, and the small town of Athabasca Landing commemorates that energetic time. The river travels through the massive oil sands north of Fort McMurray, and passes an area of migrating sand dunes that may be the largest and most northerly dune complexes in North America.

Characterization of stored peat in the Alberta oil sands area


Year: 1980

Abstract:
Properties of stored peat were studied at sites near Evansburg, Alberta, and on the lease of Syncrude Canada Ltd. at Mildred Lake, Alberta. Physical, chemical, and microbiological properties of stored materials were compared with those of fibric moss peat, mesic moss peat, and mesic fen peat samples from undisturbed sites. Environmentally induced changes in peat properties were simulated in' the laboratory by freeze-drying, air-drying, and thawing peat samples. Air-drying and, to a lesser extent, freeze drying, resulted in deterioration of physical properties and in reduction of microbial activity. The stored materials at Evansburg consisted entirely of peat whereas at Mildred Lake the materials were heterogeneous peat-mineral mixtures which were grouped as follows: group I, peat predominant; group II, sand predominant; group III, sand-clay mixture; and group IV, peat-sand mixture. Optimum temperatures for microbial activity in the storage piles occurred near the surface and decreased with depth while optimum moisture conditions occurred near the 50 cm depth. Frost penetration was not greater than 1 m in any of the piles. Storage piles consisting of peat-mineral mixtures which had been fertilized had a somewhat higher level of microbial activity and organic matter decomposition than undisturbed peat or stored, relatively pure peat. Properties of the stored materials which were highly correlated with each other were carbon, nitrogen, respiration rate, enzyme activity, cation exchange capacity, ash content, bulk density, pore volume, and water capacity. Relatively simple methods for the characterization of ash, carbon, and bulk density of stored materials were used.

Characterization of trace gases measured over Alberta oil sands mining operations: 76 speciated C2-C10 volatile organic compounds (VOCs) CO2 CH4 CO NO NO2 NOy O3 and SO2


Year: 2010

Abstract:
Oil sands comprise 30% of the world’s oil reserves and the crude oil reserves in Canada’s oil sands deposits are second only to Saudi Arabia. The extraction and processing of oil sands is much more challenging than for light sweet crude oils because of the high viscosity of the bitumen con- tained within the oil sands and because the bitumen is mixed with sand and contains chemical impurities such as sulphur. Despite these challenges, the importance of oil sands is in- creasing in the energy market. To our best knowledge this is the first peer-reviewed study to characterize volatile organic compounds (VOCs) emitted from Alberta’s oil sands mining sites. We present high-precision gas chromatography mea- surements of 76 speciated C2–C10 VOCs (alkanes, alkenes, alkynes, cycloalkanes, aromatics, monoterpenes, oxygenated hydrocarbons, halocarbons and sulphur compounds) in 17 boundary layer air samples collected over surface mining operations in northeast Alberta on 10 July 2008, using the NASA DC-8 airborne laboratory as a research platform. In addition to the VOCs, we present simultaneous measure- ments of CO2, CH4, CO, NO, NO2, NOy, O3 and SO2, which were measured in situ aboard the DC-8. Carbon dioxide, CH4 , CO, NO, NO2 , NOy , SO2 and 53 VOCs (e.g., non-methane hydrocarbons, halocarbons, sul- phur species) showed clear statistical enhancements (1.1– 397×) over the oil sands compared to local background val- Correspondence to: I. J. Simpson (isimpson@uci.edu) ues and, with the exception of CO, were greater over the oil sands than at any other time during the flight. Twenty halo- carbons (e.g., CFCs, HFCs, halons, brominated species) ei- ther were not enhanced or were minimally enhanced (<10%) over the oil sands. Ozone levels remained low because of titration by NO, and three VOCs (propyne, furan, MTBE) remained below their 3 pptv detection limit throughout the flight. Based on their correlations with one another, the com- pounds emitted by the oil sands industry fell into two groups: (1) evaporative emissions from the oil sands and its prod- ucts and/or from the diluent used to lower the viscosity of the extracted bitumen (i.e., C4 –C9 alkanes, C5 –C6 cycloalka- nes, C6–C8 aromatics), together with CO; and (2) emissions associated with the mining effort, such as upgraders (i.e., CO2, CO, CH4, NO, NO2, NOy, SO2, C2–C4 alkanes, C2– C4 alkenes, C9 aromatics, short-lived solvents such as C2Cl4 and C2 HCl3 , and longer-lived species such as HCFC-22 and HCFC-142b). Prominent in the second group, SO2 and NO were remarkably enhanced over the oil sands, with maxi- mum mixing ratios of 38.7 ppbv and 5.0 ppbv, or 383× and 319× the local background, respectively. These SO2 lev- els are comparable to maximum values measured in heavily polluted megacities such as Mexico City and are attributed to coke combustion. By contrast, relatively poor correla- tions between CH4, ethane and propane suggest low levels of natural gas leakage despite its heavy use at the surface mining sites. Instead the elevated CH4 levels are attributed to methanogenic tailings pond emissions.

Differential changes in gene expression in rainbow trout hepatocytes exposed to extracts of oil sands process-affected water and the Athabasca River


Year: 2012

Abstract:
The oil sands region of northern Alberta represents the world's largest reserves of bitumen, and the accelerated pace of industrial extraction activity has raised concern about the possible impacts on the Athabasca River and its tributaries. An ecotoxicogenomic study was undertaken on Oncorhynchus mykiss trout hepatocytes exposed to extracts of water samples near the oil sand development area, as well as to oil sands process-affected water (OSPW) extracts using the quantitative reverse transcriptase polymerase chain reaction technique. The expression of the following genes (mRNA) was monitored to track changes in xenobiotic biotransformation (CYP1A1, CYP3A4, glutathione S-transferase, multi-drug resistance transporter), estrogenicity (estrogen receptor and vitellogenin), oxidative stress (superoxide dismutase and metallothionein) and DNA repair activity (DNA ligase). The extent of DNA-aromatic hydrocarbon adducts was also determined in cells by immuno-staining. A comparative analysis of gene expression between the river/lake and OSPW samples revealed that CYP3A4, metallothioneins, DNA ligase and GST genes, were specifically expressed by OSPW. Cells exposed to OSPW, commercial naphthenic acids, and benzo(a)pyrene showed increased polyaromatic hydrocarbon DNA-adducts, as determined by cell immunofluorescence analysis. Other genes were induced by all types of water samples, although the induction potential was stronger in OSPW most of the time (e.g., VTG gene was expressed nearly 15-fold by surface waters from the lake and river samples but increased to a maximum of 31-fold in OSPW). A multivariate discriminant function analysis revealed that the lake and river water samples were well discriminated from the OSPW. The CYP3A4 gene was the most highly expressed gene in cells exposed to OSPW and responded less to the lake or river water in the Athabasca River area. This study identified a suite of gene targets that responded specifically to OSPW extracts, which could serve as toxicogenomic fingerprints of OSPW contamination. Differential changes in gene expression in rainbow trout hepatocytes exposed to extracts of oil sands process-affected water and the Athabasca River (PDF Download Available). Available from: https://www.researchgate.net/publication/221753631_Differential_changes_in_gene_expression_in_rainbow_trout_hepatocytes_exposed_to_extracts_of_oil_sands_process-affected_water_and_the_Athabasca_River [accessed Jan 18, 2016].

Energy and water exchange from a saline-sodic overburden restoration cover Fort McMurray, Alberta


Author(s): Carey, S. K.

Year: 2006

Abstract:
The Canadian oil sand mining industry takes responsibility for restoring mining areas to an equivalent level that existed before mining occurred. During this process, the surface-vegetation-atmosphere continuum is dramatically altered, creating few similarities to the boreal forest that existed prior to mining. Using the eddy covariance method, a study of the integrated salt and water balance of a saline-sodic overburden pile at Syncrude Canada Ltd.'s Mildred Lake mine north of Fort McMurray, Alberta was undertaken in order to measure the surface energy balance for three summers (2003 - 2005) with different climatic and phenological conditions. The objective of this study was to document how evapotranspiration and energy partitioning varied inter-annually during the growing season atop the restoration cover and to relate the portioning of energy at the surface to environmental and physiological variables. The paper described the site and measurement specifics and also presented the results and discussion. Results were organized under the following topics: climate; soil moisture and suction; leaf area index and vegetation; surface energy balance; evapotranspiration; and controls on evapotranspiration. It was concluded that results from this study have important implications for recovery strategies, as the availability water for plant growth, the movement and migration of salts and percolating water for deep drainage all depend on accurate quantification of evapotranspiration. 9 refs., 1 tab

Establishment report on the Mildred Lake native and cultivated grass reclamation trial


Author(s): Tomm, H. O.

Year: 1982

Abstract:
The adaptability of native and cultivated grasses to oil sands disturbances is being studied in a field trial in northeastern Alberta. The native grasses originated from the mountains and foothills of the province. The trial was established on blended materials consisting of native sand, clayey overburden and peat. Nine native grasses and eight cultivated grass varieties were seeded in June of 1981. A description of the site, a summary of experimental procedures and first-year results are included in the report.

Evaluation of groundwater flow and salt transport within an undrained tailings sand dam


Author(s): Price, A. C. R.

Year: 2005

Abstract:
Groundwater flow and salt transport in an undrained tailings sand dam is investigated at Syncrude Canada's Mildred Lake Oil Sands mine, in northeast Alberta. Two dimensional groundwater flow and salt transport are characterized using field data from two detailed piezometer transects. Calibrated steady-state groundwater flow and transient salt transport models simulate existing and future flow systems and flushing of process water. Dyke topography creates nested flow patterns, which are modified in some cases by variations in hydraulic conductivity. Greater relief of the backward-sloped bench design compared with forward-sloped benches results in larger local flow systems, a deeper water table, flushing of process water and focused discharge. Under the existing flow conditions captured by the model, salts will flush in decades at the local scale (bench) and centuries at the intermediate scale (perimeter dyke). The future flow regime will depend strongly on recharge rates across the reclaimed dam.

Evaluation of groundwater flow and salt transport within an undrained tailings sand dam


Author(s): Price, A. C. R.

Year: 2005

Abstract:
Groundwater flow and salt transport in an undrained tailings sand dam is investigated at Syncrude Canada's Mildred Lake Oil Sands mine, in northeast Alberta. Two dimensional groundwater flow and salt transport are characterized using field data from two detailed piezometer transects. Calibrated steady-state groundwater flow and transient salt transport models simulate existing and future flow systems and flushing of process water. Dyke topography creates nested flow patterns, which are modified in some cases by variations in hydraulic conductivity. Greater relief of the backward-sloped bench design compared with forward-sloped benches results in larger local flow systems, a deeper water table, flushing of process water and focused discharge. Under the existing flow conditions captured by the model, salts will flush in decades at the local scale (bench) and centuries at the intermediate scale (perimeter dyke). The future flow regime will depend strongly on recharge rates across the reclaimed dam.

Evaluation of the capability of aggregated oil sands mine tailings: Biological indicators


Year: 2003

Abstract:
An experiment was initiated in 1997 in northeast Alberta at the Syncrude Canada Ltd. Mildred Lake site to field test an innovative technique for reclamation of oil sand mine tailings. This technique was used to create an aggregated soil material from oil sand tailings. A plant community was successfully established on the soil material created by this technique. However, whether the site would be capable of supporting a self-sustainable ecosystem for the long-term remained a challenging issue. We evaluated the capability of these aggregated oil sand tailings by using biological indicators of the abundance and diversity of soil microbial biomass. Soil respiration rates and soil microbial biomass measurements were used to assess the abundance and activities of soil microbial communities. The ability of soil microbial biomass to utilize a diverse range of carbon substrates was used to assess the diversity of soil microbial communities. Soil biological activity increased with increasing growth of plant biomass and over time. Increasing the amount of peat moss or muskeg incorporated into the soil during reclamation resulted in higher organic carbon and nitrogen content and caused an increase in abundance and diversity of soil microbial biomass. These results indicate that measurements of soil respiration and substrate utilization by soil microbial communities may be used as biological indicators for assessing the capability of reclaimed soils.

Evaluation of trees and shrubs for oil sands reclamation: Field trial results


Year: 1987

Abstract:
The Alberta Oil Sands Environmental Research Program (AOSERP) Subproject VE 7.1 was initiated to select suitable tree and shrub species for use in revegetating spoils and tailings resulting from oil sands mining operations in northeastern Alberta. As part of this program three field trials were established near the Mildred Lake field camp, approximately 38 km north of Fort McMurray, in 1980 and 1981. The purpose was to test one or more provenances (seed sources) of promising native and exotic woody species. The trial site was prepared to simulate an oil sands reclamation situation. Overburden and peat were hauled to the site from Syncrude Canada Ltd.’s mining lease and incorporated in native sand. The resulting reconstructed soil was alkaline (pH 7.5), non-saline, and low in available N, P, and K. No fertilizers were added. A fine-mesh fence was erected around the trial site to exclude small mammals. All species were outplanted as one- or two-year-old container stock. All seed used to rear the native species was collected from local populations in the oil sands region. In August 1986 the trials were assessed. Survival rates were high for most species. Girdling damage by small mammals was almost non-existent, probably because of the fine-mesh fencing. Populus Northwest and P. Tristis #1 were the tallest and fastest growing species. Among the native species, Pinus banksiana was the tallest and fastest growing. Several other species also performed well and may be suitable for oil sands reclamation: Caragana arborescens, Cornus stolonifera, Elaeagnus commutata, Empetrum nigrum, Picea glauca, Picea mariana, and Populus Brooks #6. Some species gave mediocre or inconsistent performances, including Betula glandulosa, Betula papyrifera, Populus Walker, and Vaccinium vitis-idaea. The remaining species were failures and may not be adapted to the test site environment: Acer negundo, Alnus tenuifolia/crispa, Elaeagnus angustifolia, Fraxinus pennsylvanica, Lonicera tartarica, Populus tremuloides, Rosa woodsii, Salix acutifolia, Salix fragilis var. basfordiana, Salix pentandra, and Ulmus pumila. There were few significant differences among provenances for any of the native species. This suggests that genotypic differences were small among the populations tested.

Ground penetrating data radar (GPR): A new geophysical methodology used to investigate the internal structure of sedimentary deposits (field experiments on lacustrine deltas)


Author(s): Jol, H. M.

Year: 1993

Abstract:
Although in its infancy, ground penetrating radar (GPR) is rapidly emerging as a geophysical technology with many possible applications. To assess whether GPR could become a useful tool to investigate internal sedimentary structures, GPR field experiments were conducted on several modern, Holocene and Pleistocene lacustrine deltas to better understand the internal stratigraphy. A pulseEKKO$\sp{\rm TM}$ IV radar system was used with 25, 50, 100 and 200 MHz frequency antennae and 400 and 1000 V transmitter power levels. For most surveys one metre steps (station spacing) were used to provide detailed horizontal resolution of the sedimentologic structures. The profiles were processed and plotted (wiggle trace format) using pulseEKKO$\sp{\rm TM}$ IV software. Depth of reflections was determined from using the common midpoint (CMP) method. Experiments with different antennae frequencies and transmitter powers showed significant variations in vertical resolution, depth of penetration and continuity of reflections. Radar stratigraphic (facies) analysis of GPR profiles, evolved as a secondary development in this dissertation, provided identification of three deltaic types: (1) fan-foreset, (2) wave, and (3) braid. These deltaic types are in general agreement with existing concepts. Fan-foreset deltas are dominated by steeply dipping (25$\sp\circ$) reflections, sandwiched by surface and basal radar facies which have slightly inclined or horizontal reflections. Wave deltas have low-angle inclined reflections capped by discontinuous, wavy reflections. Braid deltas have distinct, continuous and semi-continuous, wavy reflections, often overlying a basal, horizontally continuous reflection, below which an abrupt signal loss occurs. As well, two post depositional features found in deltaic environments were investigated: (1) a potential failure plane and (2) a peatland. The insights gained from the radar stratigraphic analysis of deltaic environments may be extended to the interpretation of seismic records and ancient deltaic systems. More importantly, this information will provide a better understanding of the internal structure which will aid earth scientists in the interpretation of deltaic sequences from drill cores. GPR was found to be most effective (resolution and depth of penetration) in dry and/or wet (freshwater), quartzose-rich, clean (no clay) sand and gravel deposits. The technique does not work well in sediments with silt, clay, caliche (CaCO$\sb3$, calcrete), or saline ground water which attenuate the electromagnetic signal.

In the shadow of the oilsands


Year: 2011

Abstract:
A young willow branch, stuck intothe mud by a boater, marks the deepest passage from Lake Athabasca into the Athabasca Delta (top left). Fort Chipewyan's band elders are concerned that water being taken from the Athabasca River to process bitumer~ into oil is contributing to declining water levels. Tar sands processing requires almost four barrels of water for every barrel of crude produced; Alberta Energy projects production will reach 3 million barrels of oil per day by 2018. Aside from employment in the oilsands, commercial fishing is one of Fort Chipewyan's last viable means of making a living (top right). Over the last five years, more and more fish with golf-ball-sized tumours, double tails, and other abnormalities have been caught in Lake Athabasca by commercial fishermen. In 2010, fishermen in Fort Chipewyan were unable to sell any fish commercially due to growing concerns over contamination from pollution, according to Lionel Lepine, the traditional environmental knowledge coordinator for the Athabasca Chipewyan First Nation. Most of the fish caught during 2010 were smoked (bottom left) or thrown to sled dogs (bottom right).

Citation:
[Anonymous] (2011).  In the shadow of the oilsands. 44(5), 26-33. Abstract

In-situ recovery process fluids


Author(s): Peake, E., & Maclean M. A.

Year: 1988

Abstract:
The heavy oils produced from the Alberta oil sands contain cyclic organic compounds together with sulphur and nitrogen. Upon thermal treatment they have the potential to form carcinogenic, mutagenic, and toxic compounds. Recovery of oil by in-situ combustion processes, such as the Combination of Forward Combustion and Waterflood (COFCAW) process, may result in the formation of such biologically active compounds with generation dependent upon operating conditions. The objective of the present research program is to evaluate produced oils and accompanying waters from in-situ combustion processes for possible biological activity. This evaluation is based on biological testing, using the Ames test for mutagenicity and the Microtox test for toxicity, and on the chemical analysis of oils and waters for the presence of known carcinogens. For comparison, oils produced by the less thermally rigorous steam injection process, as well as naturally occurring bitumen, and synthetic crude oil and other oils produced from the Athabasca and Peace River oil sands were examined. Analysis of oils produced by in-situ combustion showed the presence of many carcinogenic and mutagenic compounds, among them the well known carcinogen benzo(a)pyrene (BaP). The BaP content of a mixture of bitumen, cracked oil, and diesel fuel produced by the COFCAW process from the Gregoire Lake pilot project contained 14 µg/g BaP. This compares with 1.5 µg/g in unaltered bitumen and 1 to 3 µg/g in most crude oils. Samples obtained from the Suffield Heavy Oil project which had not undergone rigorous thermal treatment contained from 1.5 to 7.5 µg/g benzo(a)pyrene and emulsion produced by steam injection from the Peace River Pilot project. operated by Shell Canada Resources Limited, contained 2.7 µg/g. An oil produced by dry retorting of the Athabasca oil sands contained 16 µg/g BaP. Oils produced from combustion tube experiments with Athabasca oil sand had a similar BaP content, 2.6 and 4.2 µg/g. Some tars and pitches, especially coal tars, may contain 10 to 100 times more BaP than crude petroleum. Refinery residuals, tars, and oils from Sarnia were found to contain 150 to 1050 µg/g. Benzo(a)pyrene is the best known of the carcinogens found in petroleum, but many other known or suspected carcinogens were found in greater quantities than BaP in the oils produced by in-situ combustion and dry retorting. The assessment of any carcinogenic hazard associated with petroleum is difficult. Animal tests are expensive and time consuming; therefore, short term bio-assays for mutagenic properties such as the Ames test, together with chemical analysis, are employed. Positive results in the Ames test are not an absolute indicator of carcinogenic potential. Mutagenicity does not in all cases imply carcinogenicity; however, those polycyclic aromatic hydrocarbons which are carcinogenic are also mutagenic in the Ames test when appropriate enzymes are included. Mutagenic activity was found with the Ames test in oils produced from the Gregoire Lake. Suffield, and Peace River in-situ pilot projects and in vacuum gas oil and pitch from the Peace River diluent recovery unit. The mutagenicity was less than predicted from the amount of carcinogenic aromatic compounds found by chemical analysis. The complex mixture of hydrocarbons which comprises these oils suppressed the activity of the carcinogens in the Ames test. Thus the Ames test was found to be an indicator of mutagenic activity but not a quantitative method for assessing the relative mutagenicity of oils. Synthetic crude oil produced from Athabasca bitumen displayed some mutagenic activity but, despite the presence of BaP, the bitumen itself did not. Waters produced during in-situ recovery of oil by both steam stimulation and combustion processes were toxic to aquatic organisms as determined by the Microtox bioluminescence assay. EC 50 values, the effective concentration of toxicant causing a 50% decrease in the light output of a photoluminescent bacteria, ranged from 0.30 to 11. The toxicity was caused partly by volatile organic compounds, primarily alkyl substituted benzenes, and partly by extractable organic compounds including phenols, organic acids, and hydrocarbons with no single class of compounds solely responsible for the observed toxicity. Wastewaters from the dry retorting process were more toxic than waters produced by in-situ combustion and contained many aromatic hydrocarbons and nitrogen compounds known to be biologically active. The chemical analyses and limited biological testing carried out in this study detected no strong mutagenic or carcinogenic hazard associated with in-situ recovery of heavy oil by combustion and steam injection. The relative hazard is probably marginally greater than that associated with production of conventional light crude oils but far less than might be expected from coal liquefaction processes or from disposal of refinery residuals. The hazard associated with dry retorting is greater than that from in-situ recovery methods and care should be taken in the handling of both products and wastewaters from this process.

Indigenous knowledge of the land and protected areas: Fond du Lac Denesuline Nation and the Athabasca Sand Dunes, Saskatchewan


Author(s): Yantz, J. L.

Year: 2005

Abstract:
Many Aboriginal Nations in Canada seek to be involved in protected areas planning and overall land management. In a partnership study conducted with Fond du Lac Denesuline Nation in northern Saskatchewan, the cultural and ecological uses of land and resources were documented for the Athabasca sand dunes region on the south shore of Lake Athabasca. Denesuline land uses provided a basis to discuss the role of traditional land use and indigenous knowledge in the co-stewardship of protected areas in Saskatchewan. Gathering indigenous knowledge in Fond du Lac Denesuline Nation involved a participatory research design developed through community meetings and study team working groups. Interviews and individual map biographies resulted in a collection of composite maps. The thesis does not include material considered confidential by indigenous knowledge holders. The partnership study was part of a larger project entitled "Respecting and Preserving Fond du Lac Denesuline Indigenous Knowledge: thai gayé, ethedustél túe", published by Fond du Lac Denesuline Nation (2004). (Abstract shortened by UMI.)

Interim report of soil research related to revegetation of the oil sands area


Year: 1980

Abstract:
Monitoring was continued at instrumented sites which were selected in spring 1976, at Mildred Lake, Supertest Hill, the GCOS dike, and near Richardson Tower. Because of budget limitations, sites at Richardson were only monitored occasionally. However, information was obtained at a number of temporary 'outlying sites', which showed that conditions at the instrumented sites are fairly representative of those under similar vegetation in the surrounding area. Special emphasis in 1977, was placed on obtaining detailed information on moisture tensions using thermocouple psychrometers, and in acquiring accurate information on changes in moisture distribution during spring thaw. Growth of grasses and legumes in tailings sand, and the effect of adding materials such as peat and glacial till to tailings sand, were studied using lysimeters both indoors and in the field, and by establishing small plots, all of which were instrumented for gathering of physical and chemical information. Aspects of nutrient cycling such as nutrient inputs and outputs at forest sites, nitrogen mineralization and immobilization, retention of nitrogen by soil mixes, and decomposition of plant materials, were investigated with 15N and 14C. Laboratory studies were carried out on nitrogen and carbon cycling in tailings sand and two overburden materials. Much interpretation of information gathered over the year is still to be done and will be included in the next report.

Interim report on characterization and utilization of peat in the Athabasca oil sands area


Year: 1979

Abstract:
Two sites have been established for the study of stored peat. These are located at Evansburg ; Alberta and on the Syncrude Canada Ltd. lease at Mildred Lake, Alberta. Fibric and mesic moss peat and fen peat have been investigated in terms of their physical, chemical and microbiological properties. Such material will eventually be stored at mining sites in the AOSERP study area, presumably for later use as an amendment to aid reclamation procedures. The main purpose of this research was to quantify the changes in chemical, physical and microbiological properties that are likely to take place in the peat after a period of prolonged storage. A freeze-dry, air-dry, and thaw experiment was initiated to assess the rate of decomposition in stores peat. This indicated that drying affects most physical properties of peat. Drying affects the microbial activity in peat as measured by enzyme activity and CO2 production. Generally freeze-drying appeared less detrimental than air drying. The stored material at Evansburg was essentially composed of peat, whereas at Mildred Lake the material was a heterogeneous mixture of peat and inorganic material (sand, silt and clay). Both sites were instrumented with fiberglass temperature-moisture cells in order to record the annual variation in temperature and moisture in the stored material. Cellulotytic activity was measured by imbedding filter paper in the stored material at both Evansburg and Mildred Lake. Initial results indicate greater cellulose decomposition in the mixed peat material at Mildred Lake than at Evansburg. A higher rate of CO2 evolution from the Mildred Lake samples indicated greater microbiological activity at this site. This increased activity may be attributed to the presence of the inorganic constituents in the pile and to the application of commercial fertilizer. In the investigation of the Mildred Lake stored material, positive correlations have been established between carbon content, and microbiological activity, enzyme activity, and cation exchange capacity. Those samples containing the greatest amount of peat were highest in microbiological and enzyme activity thus indicating a possible greater rate of decomposition. Unlike the stored material, undisturbed peat near Mildred Lake showed little activity. A similar investigation into the activity in the peat storage pile at Evansburg will be undertaken in 1978.

Long term prediction of vegetation performance on mined sands


Author(s): Bliss, L. C.

Year: 1977

Abstract:
This project on the \"Long Term Prediction of Vegetation Performance On Mined Sands\" (V.E.6.1) was undertaken to provide management with answers on the predictive ability to maintain different kinds of vegetation on raw sands. The research was designed as an integrated, multi-disciplinary program that would concentrate on the role of water stress in a dynamic soil-plant-atmosphere system of a planted grass cover and a natural Jack pine forest. To date only the latter project has been initiated because of the lack of funding and approval to work on the GCOS dike in 1975. This and the Syncrude dyke represent the worst (driest) environmental situation and therefore revegetation of other sand deposits should be more easily accomplished. The Richardson Fire Tower site was chosen because of the representativeness of its Jack pine - lichen woodland on deep sands, a forest type so characteristic of northeastern Alberta. The results of the first full year show that climatically this southwest-facing sand slope warms more rapidly in spring than do level sites at Mildred Lake and Fort McMurray and that the 1976 summer was above normal for temperature. Precipitation was near normal based upon the 1941 - 1970 period. Of the >60 days of precipitation, over 60% were 4 mm or less and thus little if any water entered the soil due to tree, lichen, and litter interception. Both needle duff and lichens provide a significant barrier to surface evaporation compared with open sand. Resistance to evaporation is 2 to 3 times greater with a lichen cover than with litter. The soils are very porous which is advantageous for water entrance, thus preventing erosion but porosity is a disadvantage in maintaining higher water levels near the soil surface for plant growth. These soils recharge during snowmelt in late March - early April; little runoff occurs and over the summer soil water drawdown takes place. Soil moisture content (volume basis) is generally 8 - 15% near the surface in spring, but by late September is 1 - 3% at all depths. Xylem water potentials, a measure of tree water content, were never very low (mean maximum at dawn -5 to -7 atm. and mean minimum at midday -11 to -14 atm.) which reflect a year of average precipitation with frequent light rains and periodic heavier storms. Transpiration and stomatal closure were controlled largely by vapour pressure deficits. Jack pine avoided spring drought by remaining dormant when air and needle temperatures were above freezing, yet when soils were still frozen. Although Jack pine did not show indications of severe drought in a relatively moist summer, it did develop xylem water potentials of -16 to -18 atm., values which are probably detrimental to many of the species being used in revegetation trials on the dike (Bromus inermis, Phleum pratense, and species of Agropyron). This means that potential species must be drought hardy and tested under laboratory rather than only under field conditions to determine their survival under severe drought conditions that may occur but once in 30 to 50 years. The studies of mycorrhizae show that a large number of species of fungi infect the roots of Jack pine and that the infecting flora from disturbed soils (old burns) is quite different from that of undisturbed forests. Since mycorrhizae are critical for the proper growth and survival of pines, care in innoculating tree seedlings with the proper species is essential. The energy and water balance mathematical model predicts the heat and water status of the Jack pine forest. Examination of the model outputs suggests that late season resistance to water uptake occurs because of increased root resistance in autumn. If this is confirmed with further experimental data, and model runs, it means that fall droughts may be especially critical because of the reduced ability of the trees to absorb water through their roots. A second field season coupled with the laboratory studies to determine lethal and sublethal levels of water stress in Jack pine will provide the added inputs to the models necessary for predicting tree response to severe climatic stress. These data, gathered in a highly integrated manner, will permit the calculation of tree survival on sands, be they dikes or other kinds of mined sand, in terms of soil water content and tree density (including crown extent) in relation to the exceptional dry year that may occur once in 30 to 50 years. Data from field trials of grasses or woody species, without supporting measurements of plant physiological responses to environmental conditions cannot provide this essential predictive tool for management unless the one in 30 to 50 year drought cycle is encountered. It is for this reason that modelling of the data in order to predict plant response to unusual environmental conditions becomes so useful. In summary, this study should be able to provide sufficient data to determine whether or not an open stand of Jack pine or similar conifer is the desired end point in maintaining vegetation at a low maintenance cost on sands, the result of open pit mining of the oil sands.

Mammalian toxicity of naphthenic acids derived from the Athabasca oil sands


Author(s): Rogers, V. V.

Year: 2003

Abstract:
Naphthenic acids are a diverse group of saturated mono- and polycyclic carboxylic acids that are natural constituents of petroleum. These compounds are a major contributor to petroleum's acidic nature and can account for as much as 4% of crude petroleum by weight. At the Athabasca oil sands (AOS) located in northeastern Alberta, Canada, naphthenic acids have received considerable attention. The AOS represent the world's largest, single petroleum deposit, where the petroleum is in the form of bitumen. Extracting bitumen from AOS is a complex process, requiring the mixing of oil sands with hot,alkaline (pH = 8.0) water to separate the bitumen from sand and other waste products. This process produces an immense volume of aqueous tailings, about 7.5 m 3 for each m3 of synthetic crude petroleum produced. Nearly one billion cubic meters of aqueous tailings will have amassed in large holding ponds near the mine sites by 2025, and will be incorporated into the ecosystem under wet and dry landscape reclamation strategies. Another consequence of the extraction process is that naphthenic acids (pKa ≅ 5) become solubilized and concentrated (90--110 mg/L) in aqueous tailings. Numerous studies have investigated the aquatic toxicity of naphthenic acids, demonstrating them to be highly toxic to invertebrates and fish at concentrations well below those found in AOS tailings. In contrast, information about the mammalian toxicity of naphthenic acids is limited, particularly the effects of repeated, oral exposure. In the current research, naphthenic acids were isolated from tailings obtained from Mildred Lake settling basin, the main tailings pond of Syncrude Canada Ltd, and used in mammalian toxicity testing. An acidification/solvent extraction procedure was used, followed by ultrafiltration to isolate the naphthenic acids. These were chemically analysed, revealing a highly heterogenous mixture of acyclic and 1-, 2-, 3-, and 4-ringed compounds. Acute testing using Wistar rats demonstrated significant (P < 0.05) behavioural and histopathological effects in both sexes at a single dosage of 300 mg/kg body weight of napthenic acids. This dosage is 50 times higher than the estimated worst-case, single day environmental exposure through drinking water for small mammals in the wild. Effects included temporary suppression of appetite, and pericholangitis, a biliary inflammatory response. Subchronic dosing, involving administration of naphthenic acids to females over a 90 d period, indicated that 60 mg/kg/d was sufficient to elicit significant (P < 0.05), toxic effects.

Methane emissions from oil sand tailings by microbial metabolism of hydrocarbons


Author(s): Siddique, T., & Foght J.

Year: 2011

Abstract:
Enormous volumes of tailings produced during bitumen extraction from oil sands ores are stored in settling basins/tailings ponds. The current inventory of tailings in northern Alberta, Canada exceeds 850 million m3. Biogenic methane emissions have been observed from the surfaces of tailings ponds and about 40 million L of methane day-1 was estimated from a single tailings pond (Mildred Lake Settling Basin) in 1999. This research project was initiated to investigate the source and mechanism of methane emission from the oil sands tailings ponds. The mature fine tailings (MFT) were collected from Syncrude Canada Ltd. and Shell Albian Sands tailings ponds and investigated for methanogenic biodegradation of solvent hydrocarbons that are used in the bitumen extraction process and the residual fractions of these solvents that are present in the tailings deposited in the tailings ponds. Our laboratory experiments have shown that only short-chain n-alkanes (C6-C10) and certain monoaromatics (BTEX) present in C3-C14 range hydrocarbons entrained in Syncrude tailings are readily biodegraded by the indigenous microorganism in the tailings ponds to produce methane. In contrast, a very long acclimation period has been observed for indigenous microbes to degrade long-chain n-alkanes (C14-18) and branched alkanes such as 2-methylpentane. Experiments are in progress to monitor the degradation of these recalcitrant compounds. The molecular analysis of 16S rRNA genes revealed that different microbial communities are involved in the degradation of different groups of petroleum hydrocarbon in oil sands tailings. Understanding the mechanism(s) of biogenic methane production and predicting emissions from oil sands tailings ponds are important objectives for effective management of tailings and greenhouse gas emissions.

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