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Health assessment of tree swallows (<i>tachycineta bicolor</i>) nesting on the Athabasca Oil Sands, AlbertaGentes, Marie-Line 08 February 2007
Oil sands mining companies in Alberta, Canada, are planning to create wetlands for the bioremediation of mining waste materials as part of a reclamation strategy. To assess feasibility, experimental wetlands mimicking proposed reclamation scenarios were constructed on mining leases. This research assessed the health of tree swallows (<i>Tachycineta bicolor</i>) nesting on these sites where they were naturally exposed to a mixture of chemicals including unrecovered bitumen, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs). Endpoints reflecting health were compared among three experimental wetlands and one reference site. In order to specifically investigate toxicity of NAs to birds, an experimental exposure to NAs was also conducted on a subset of nestlings on the reference site. <p> In 2003 and 2004, approximately 50 breeding pairs (total, per year) nesting on the following sites were monitored: Suncors Consolidated Tailings and Natural Wetlands; Syncrudes Demo Pond and Poplar Creek reference site. In 2003, reproductive success was very low on OSPM-sites compared to the reference site, but was relatively unaffected in 2004. Compromised reproductive performance in 2003 was linked to harsh weather, during which mortality rates of nestlings reached 100% on the site with the highest levels of PAHs and NAs, while they did not surpass 50% on the reference site. In 2004, mortality rates were low but nestlings from OSPM-sites weighed less and showed greater hepatic detoxification efforts (etoxyresorufin-o-deethylase activity) than those on the reference site. Furthermore, nestlings on OSPM-sites exhibited higher levels of thyroid hormones and suffered parasitic burdens (Protocalliphora spp.) approximately twice that of those on the reference site. Several of these findings may be associated with low post-fledging survival, suggesting that wet landscape reclamation strategy is not optimal for avian species and may require improvement. <p> As part of a separate study investigating toxicity of naphthenic acids, twenty nestlings from the reference site were randomly selected for an experimental exposure. Nestlings received 0.1 ml/day of NAs (15g/L) orally from day 7 to day 13 of age while being reared normally by their free-ranging parents. Nestling growth, hematocrit, blood biochemistry, organ weights and etoxyresorufin-o-deethylase activity (EROD) activity appeared unaffected by naphthenic acids. No toxic changes were detected on histopathological evaluation of major organs. These findings suggest that for nestlings reared on oil sands reclaimed sites, exposure to other chemicals such as polycyclic aromatic hydrocarbons is a greater concern than exposure to NAs. However, this study did not investigate the chronic or reproductive toxicity of naphthenic acids. More research still needs to be conducted as a part of an assessment of the sustainability of wet landscape reclamation because a previous study found that chronic exposure to NAs severely compromised reproduction in mammals.
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Health assessment of tree swallows (<i>tachycineta bicolor</i>) nesting on the Athabasca Oil Sands, AlbertaGentes, Marie-Line 08 February 2007 (has links)
Oil sands mining companies in Alberta, Canada, are planning to create wetlands for the bioremediation of mining waste materials as part of a reclamation strategy. To assess feasibility, experimental wetlands mimicking proposed reclamation scenarios were constructed on mining leases. This research assessed the health of tree swallows (<i>Tachycineta bicolor</i>) nesting on these sites where they were naturally exposed to a mixture of chemicals including unrecovered bitumen, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs). Endpoints reflecting health were compared among three experimental wetlands and one reference site. In order to specifically investigate toxicity of NAs to birds, an experimental exposure to NAs was also conducted on a subset of nestlings on the reference site. <p> In 2003 and 2004, approximately 50 breeding pairs (total, per year) nesting on the following sites were monitored: Suncors Consolidated Tailings and Natural Wetlands; Syncrudes Demo Pond and Poplar Creek reference site. In 2003, reproductive success was very low on OSPM-sites compared to the reference site, but was relatively unaffected in 2004. Compromised reproductive performance in 2003 was linked to harsh weather, during which mortality rates of nestlings reached 100% on the site with the highest levels of PAHs and NAs, while they did not surpass 50% on the reference site. In 2004, mortality rates were low but nestlings from OSPM-sites weighed less and showed greater hepatic detoxification efforts (etoxyresorufin-o-deethylase activity) than those on the reference site. Furthermore, nestlings on OSPM-sites exhibited higher levels of thyroid hormones and suffered parasitic burdens (Protocalliphora spp.) approximately twice that of those on the reference site. Several of these findings may be associated with low post-fledging survival, suggesting that wet landscape reclamation strategy is not optimal for avian species and may require improvement. <p> As part of a separate study investigating toxicity of naphthenic acids, twenty nestlings from the reference site were randomly selected for an experimental exposure. Nestlings received 0.1 ml/day of NAs (15g/L) orally from day 7 to day 13 of age while being reared normally by their free-ranging parents. Nestling growth, hematocrit, blood biochemistry, organ weights and etoxyresorufin-o-deethylase activity (EROD) activity appeared unaffected by naphthenic acids. No toxic changes were detected on histopathological evaluation of major organs. These findings suggest that for nestlings reared on oil sands reclaimed sites, exposure to other chemicals such as polycyclic aromatic hydrocarbons is a greater concern than exposure to NAs. However, this study did not investigate the chronic or reproductive toxicity of naphthenic acids. More research still needs to be conducted as a part of an assessment of the sustainability of wet landscape reclamation because a previous study found that chronic exposure to NAs severely compromised reproduction in mammals.
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Hydrological and Hydrochemical Dynamics of a Constructed Peatland in the Athabasca Oil Sands Region: Linking Patterns to TrajectoryBiagi, Kelly January 2021 (has links)
Peatlands comprise of approximately half of the Athabasca oil sands region, many of which overlay some of the world’s largest bitumen deposits where surface mining for this resource has permanently altered the landscape. By law, companies must reclaim disturbed landscapes into functioning ecosystems including integrated upland-wetland systems with the objective of forming sustainable peat-forming wetlands. This thesis presents six years (2013 – 2018) of water balance and associated salinity data from one of the two existing constructed upland-wetland systems, the Sandhill Fen Watershed (SFW), a 52-ha upland-wetland built on soft tailings to evaluate the hydrological and hydrochemical performance and its potential to be self-sustaining.
Following a considerable decrease in hydrological management, the dominant water balance components changed from primarily horizontal (inflow and outflow) to vertical fluxes (precipitation and evapotranspiration) which increased inundation, encouraged salt accumulation and changed plant communities. Results suggest that current conditions are not favourable for fen-peatland development as marsh-like conditions have developed, limiting water conserving functions and the ability to persist long-term in a changing climate.
In terms of winter processes, topography currently controls snow accumulation, redistribution and melt at SFW while the role of vegetation in these processes is expected to increase as it continues to develop. Runoff ratios of snowmelt from hillslopes were drastically different than those previously reported for reclaimed peatland watersheds highlighting the influence of different soil materials used during construction. Under various climate change scenarios of a warmer and wetter climate, results from the Cold Regions Hydrological Model indicate that the influence of winter processes will decrease, potentially putting reclaimed systems at greater risk of moisture stress.
Substantial hydrochemical changes have occurred as salinity was relatively low at the study onset as high volumes of inflow and outflow prevented ion accumulation. Over time, salinity continued to increase year-over-year throughout SFW from 2013 to 2018 in the wetland and margin areas. This increase in site-wide salinity was attributed to the shift in dominant water balance fluxes, changes in water table position and increased mixing of SFW waters with deeper saline groundwater that underlies the system. Based on its current conditions, it is unlikely that SFW will support peat-forming vegetation. It is recommended that design strategies shift to incorporate characteristics found in undisturbed saline peatlands that are capable of supporting peat-forming vegetation in a saline environment. / Thesis / Doctor of Philosophy (PhD) / A better understanding of the hydrological functioning of reconstructed peatlands in the Athabasca oil sands region is required as it is a novel approach in this region and there is potential for thousands of hectares of land that will require this reclamation in the future. Due to their recent establishment potential trajectories of constructed peatlands have yet to be fully analyzed as only recently has sufficient data been collected to evaluate the hydrological and hydrochemical functioning and provide insight on its overall success. While design strategies may seem sound, these constructed systems are completely human-made and it is unclear how they will develop and function in a highly disturbed landscape. Thesis results suggest that current conditions are not favourable to sustain a peatland as marsh-like conditions have developed which will limit its ability to persist long-term in a dry and changing climate. It is recommended that design strategies shift to incorporate characteristics found in undisturbed saline peatlands that are capable of supporting peat-forming vegetation in a saline environment. Due to the many challenges associated with reclamation in this region, lessons learned from this pilot project will help guide future peatland construction.
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Plant growth promotion on and phytoremediation of Athabasca oil sands coarse tailings using the endophytic fungus, Trichoderma harzianum TSTh20-12014 February 1900 (has links)
The environmental impact of bitumen mining in the Athabasca region of Canada is of growing concern. Among these concerns is the need and difficulty to remediate and reclaim affected land, including tailing sands (TS), a byproduct of the hot water extraction used to separate bitumen from solid materials. Current reclamation methods consist of multiple steps and take several decades to be effective. The primary reason for the difficulty in reclaiming disturbed land is the harsh environment found within the TS combined with the scale of the problem. TS are extremely nutrient poor, having below-detectable levels of NPK and extremely low C and S. In addition to this TS have pHs outside of environmental normals, and are hydrophobic due to residual hydrocarbons. Previously, an endophytic fungus, Trichoderma harzianum strain TSTh20-1, was isolated from pioneer plants growing naturally on TS sites, and was found to promote plant growth on TS. In my study TSTh20-1 was also found to increase the rate of drought recovery, and to enhance seed germination rates on a variety of soils. Suitable application methods were explored for this endophyte, including seed coatings, granules, as well as direct application to plant/soil. Regardless of method, TSTh20-1 was found to successfully colonize the plants.
Twenty-four species of grasses, forbs, and legumes were tested for their ability to grow on TS. The four most successful species (Trifolium repens, Bouteloua gracilis, Medicago sativa, and Elymus trachycaulus) were put into a seed mixture for use in experiments. In mesocosm-scale experiments, plant health and soil parameters were measured after 2 months of growth. Hydrocarbon analysis of the first mesocosm showed a 2.7-fold increase in total hydrocarbons when TSTh20-1 and plants were present, suggesting degradation of large hydrocarbons beyond the scope of the analysis. A repeat experiment using a different source of tailings did not yield this same result. This is most likely due using a source of tailings that had substantially different chemical characteristics. TSTh20-1 was also analyzed for its ability to produce plant hormones or siderophores, to increase peroxidase enzyme activity, to protect plants from reactive oxygen species, and to solubilize phosphate precipitates from soil. All of these are known mechanisms microbes use to promote plant growth.
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The mobility of petroleum hydrocarbons in Athabasca oil sands tailings2013 September 1900 (has links)
Several oil sands tailings from Suncor Energy Inc. were analysed with respect to the mobility and solubility of the petroleum hydrocarbon (PHC) contaminants. At sites where oil sands tailings materials have been disposed of and are covered with a growing medium, the PHCs from
the tailings may slowly migrate into the reclamation cover, increasing their availability to the plants in the cover system, which could be detrimental to the development and establishment of
the plant cover system.
This study characterized the PHC content of the tailings and quantified the desorption and diffusion coefficients for F2 and F3 fraction PHCs. All tailings materials collected from Suncor
were characterized for initial PHC content. Desorption coefficients were experimentally determined using batch tests for 9 tailings materials (MFT, LG MFT, PT MFT, Tailings Sand, P4 UB Surface, P4 UB Auger, 2:1 CT, 4:1 CT and 6:1 CT). The experimental results from the
batch tests were fitted to a Langmuir hyperbolic isotherm model. Diffusion coefficients were determined by fitting the experimental results from a radial diffusion 1-dimensional experiment to a Finite Difference Model. Diffusion coefficients for F2 and F3 Fraction PHCs were developed for 7 tailings materials (MFT, LG MFT, PT MFT, Tailings Sand, 2:1 CT, 4:1 CT and
6:1 CT). The diffusion coefficients (D*) and the Langmuir desorption constants ( and )
developed from these experiments are included in Table A.1.
The desorption coefficients resulting from this study are similar to those reported for the desorption of asphaltene, which is one of the components in oil sands tailings. The Langmuir isotherm model was found to be the best fit for the experimental desorption data; the Langmuir isotherm model is commonly used in sorption isotherms of organic chemicals.
The results of the radial diffusion experiments agree with diffusion rates found by other researchers in similar porous media. More research may be needed to verify both of these preliminary results for the desorptive and diffusive transport of F2 and F3 PHC fractions in tailings. Tailings composition will continue to change as new technologies for fines settling and bitumen extraction are developed. The diffusion of PHCs from these new materials will need to be examined as it is probable that these changes will affect the transport and mobility of the contaminants.
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Disturbance Related Patterns in Fish Community Structure and Function in River Systems of the Lower Athabasca Oil Sands Region, AlbertaMcFadyen, Shannon Ashley 13 January 2016 (has links)
Anthropogenic development is altering watersheds and threatening freshwater ecosystems and the resources therein. Direct impacts of industry including conversion of land cover and increased water withdrawals from rivers, compounded with indirect influences such as climate change, collectively affect the health and sustainability of freshwater ecosystems. Many studies have indicated a suite of ecological impacts that large-scale anthropogenic land use and development impose on the structure and function of riverine systems. The overarching goal of this thesis was to examine the potential impacts associated with land use disturbance and Oil Sands (OS) mining operations on fish community composition patterns in three rivers located in the Athabasca Oil Sands Region (AOSR). Using historical data sets, this thesis attempted to evaluate disturbance-related patterns in fish community composition. Fish community-environmental relationships were investigated on a temporal scale, across which community composition could be constrained or altered by development. Structural and trait-based changes in fish community composition were analyzed to determine whether significant variation between levels of development (pre versus post) in the AOSR could be attributed to observed changes in fish community metrics. No significant difference in community composition patterns was observed between levels of development; however, there was a significant decline in fish species richness on a regional scale. The lack of significant results could be attributed to the limitations of the collected data, including temporal gaps, inconsistent sampling methods, and seasonal sampling inconsistencies. Furthermore, the scale of interpretation between individual tributaries and the regional datasets, demonstrates that studies of fish communities on a regional scale can elucidate different states of community change, implying that local controls can play a role in species presence/absence.
An assessment of the features and patterns of the hydrograph that could explain variation in fish communities was constrained due to dataset and subsequent methodological limitations. Currently, there is an inability to link changes (historical) to hydrologic regimes, land use or development within these systems, and how they have impacted fish communities therein due to inconsistencies in the methods and sampling during most of the pre-development and for a portion of post- development time span (until 2009). Long-term, standardized community monitoring will be critical to gain a greater understanding of how land management practices affect fish communities and what kind of ecosystem management can mitigate impacts to streams, rivers and the biota therein. Further recommendations were made from synthesizing these findings in conjunction with relevant literature and are intended to provide an improved understanding of the long-term cumulative changes within these systems and to help guide and improve future monitoring plans in the AOSR. / Graduate
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Ecological Response of Atmospheric Nitrogen Deposition on Reconstructed Soils in the Athabasca Oil Sands RegionHemsley, Tyrel, Lee Unknown Date
No description available.
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DISCONNECT: Assessing and Managing the Social Effects of Development in the Athabasca Oil SandsEarley, Robert January 2003 (has links)
This research investigated the system by which the social effects of oil sands development on Fort McMurray, a city in northeastern Alberta, are assessed and managed. The research focused on Social Impact Assessment (SIA), Strategic Environmental Assessment (SEA), and the work of an industry initiative, the Regional Issues Working Group (RIWG). The oil sands industry, which involves large, labour-intensive mining and drilling operations in a boom-bust cycle, places considerable pressure on Fort McMurray, a city of approximately 50,000 inhabitants and the only urban area within 350 km of the oil sands. The social effects experienced there include exorbitant housing prices, shortages in service industry labour, insufficient social services, at times, to assist individuals and families who can no longer cope with the difficult conditions in the area, and a variety of other negative effects.
Sixteen key informant interviews were conducted with urban planners, municipal politicians, provincial employees, a spokesperson for one of the First Nations in the area, community NGOs, and oil sands industry representatives. Data from the interviews were combined with a literature review and a document analysis. A modified McKinsey 7S Integrated Management Framework was used as a structure for describing and analyzing the Social Effects Assessment and Management System (SEAMS) in Fort McMurray.
The SEAMS was found to be weak in comparison to the needs of the community. Project-by-project assessment of oil sands development was found to downplay the cumulative nature of social effects. Furthermore, no legislation or regulation existed that demanded action based on the findings of SIA. As a result, mitigation and management of social effects was insufficient, often occurring only when it was directly in the interests of the oil sands industry. While government and industry have plans in place to resolve some of the negative social effects, their actions were criticized by informants as being uncoordinated, inconsistent and often ineffective.
The findings indicate that a strategy for exploiting Alberta's oil sands is necessary. The project-by-project evaluation of oil sands development proposals is not addressing the important long-term and regional social issues that arise as a result of construction and operation of the mines and facilities. A tool recommended for incorporating resolutions to long-term, regional social effects into the development plan is SEA with an explicit Strategic Social Assessment component. This strategic assessment and planning process should be undertaken by a publicly-accountable government body empowered to rationalize the pace of oil sands development based on social, environmental and economic effects, and to coordinate long-term responses by government and industry.
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DISCONNECT: Assessing and Managing the Social Effects of Development in the Athabasca Oil SandsEarley, Robert January 2003 (has links)
This research investigated the system by which the social effects of oil sands development on Fort McMurray, a city in northeastern Alberta, are assessed and managed. The research focused on Social Impact Assessment (SIA), Strategic Environmental Assessment (SEA), and the work of an industry initiative, the Regional Issues Working Group (RIWG). The oil sands industry, which involves large, labour-intensive mining and drilling operations in a boom-bust cycle, places considerable pressure on Fort McMurray, a city of approximately 50,000 inhabitants and the only urban area within 350 km of the oil sands. The social effects experienced there include exorbitant housing prices, shortages in service industry labour, insufficient social services, at times, to assist individuals and families who can no longer cope with the difficult conditions in the area, and a variety of other negative effects.
Sixteen key informant interviews were conducted with urban planners, municipal politicians, provincial employees, a spokesperson for one of the First Nations in the area, community NGOs, and oil sands industry representatives. Data from the interviews were combined with a literature review and a document analysis. A modified McKinsey 7S Integrated Management Framework was used as a structure for describing and analyzing the Social Effects Assessment and Management System (SEAMS) in Fort McMurray.
The SEAMS was found to be weak in comparison to the needs of the community. Project-by-project assessment of oil sands development was found to downplay the cumulative nature of social effects. Furthermore, no legislation or regulation existed that demanded action based on the findings of SIA. As a result, mitigation and management of social effects was insufficient, often occurring only when it was directly in the interests of the oil sands industry. While government and industry have plans in place to resolve some of the negative social effects, their actions were criticized by informants as being uncoordinated, inconsistent and often ineffective.
The findings indicate that a strategy for exploiting Alberta's oil sands is necessary. The project-by-project evaluation of oil sands development proposals is not addressing the important long-term and regional social issues that arise as a result of construction and operation of the mines and facilities. A tool recommended for incorporating resolutions to long-term, regional social effects into the development plan is SEA with an explicit Strategic Social Assessment component. This strategic assessment and planning process should be undertaken by a publicly-accountable government body empowered to rationalize the pace of oil sands development based on social, environmental and economic effects, and to coordinate long-term responses by government and industry.
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Effects of oil sands process-affected water and substrates on wood frog (<i>Rana sylvatica</i>) eggs and tadpolesGupta, Niti 27 May 2009
An essential element of the reclamation strategy proposed by the oil sands mining industry in northern Alberta, Canada, includes the creation of wetlands for the bioremediation of mining waste materials. The mining process used to extract oil from these deposits results in the production of large volumes of process-affected water (OSPW) and sediments (OSPS), which must be incorporated into wetlands as a component of the reclaimed landscapes. Wood frogs (<i>Rana sylvatica</i>) are an abundant native species that might be expected to inhabit these reclaimed wetlands. The objective of this study was to determine potential detrimental effects of OSPW and OSPS on the growth and development of wood frogs. Several morphological (weight, length, condition factor) and biochemical (whole body tadpole thyroid hormone and triglyceride concentrations and metamorph hepatic glycogen concentration) endpoints were assessed in conjunction with hatchability and survivability of wood frog eggs and tadpoles exposed to process-affected materials (OSPM) under field and laboratory conditions.<p>
As part of this study, assay techniques were optimized to enable simultaneous measurement of whole body 3,5,3-triiodothyronine (T3), thyroxine (T4) and triglyceride (TG) concentrations in wood frog tadpoles. These assays were used to monitor changes in T3, T4 and TG in wood frog tadpoles during development from hatching to metamorphosis (Gosner stages 19-46), to establish baseline levels for subsequent application of the assays to evaluate contaminant effects. The results indicated peak T3 and T4 concentrations occurred during metamorphic climax (Gosner stages 40-46) and prometamorphosis (Gosner stages 31-40), respectively. Maximal TG concentrations were also observed during prometamorphosis. These assays were further employed to assess body condition and development in wood frogs during a field study in 2005, and the following laboratory studies in 2006 and 2007.<p>
In summer 2005, 29 reclaimed and five unimpacted wetlands were monitored for use by native amphibians, and tadpoles and newly-metamorphosed wood frogs were collected from a subset of sites as a preliminary assessment of contaminant effects. Endpoints such as metamorph hepatic glycogen and whole body tadpole T3, T4 and triglyceride concentrations were compared among six impacted and three reference wetlands. The surveys indicated 60% of OSPW-impacted wetlands were used by breeding adult amphibians, while wood frog tadpoles and newly-metamorphosed frogs were observed in 37 and 30% of OSPW wetlands, respectively. In general, lower whole body tadpole T3 and triglyceride concentrations were observed in wood frogs from wetlands containing OSPM. In contrast, hepatic glycogen concentrations in newly-metamorphosed frogs and whole body tadpole T4 and T3/T4 concentrations were comparable among the reference and impacted wetlands. In addition, the differences observed in total body weight and length of tadpoles and newly-metamorphosed wood frogs among OSPM and reference sites were likely due to minor differences in developmental stages of the animals collected from the various wetlands, rather than any contaminant effect.<p>
In 2006 and 2007, wood frog eggs and tadpoles were exposed to several sources of OSPW and OSPS collected from reclaimed Suncor and Syncrude wetlands under controlled laboratory conditions. Hatchability was reduced in eggs exposed to water from only one of the OSPW sites, compared with the other process-affected ponds and the control water (P<0.05). In contrast, survivability of tadpoles was significantly reduced (P<0.05) in all the impacted sites in both years, with nearly all OSPW sites having <10% survival. The exposure study evaluated the toxicity of five types of OSPS. Results indicated no impact of OSPS exposure on survivability of tadpoles, but showed reduced whole body weight (in three OSPS treatments), length (in two OSPS treatments) and body condition (in one OSPS) of tadpoles exposed to process-affected substrates tested (P<0.05). Whole body T3 and T4 concentrations in tadpoles from OSPS treatments were not different from the control treatment, but tadpole TG concentration was reduced in groups exposed to two impacted substrates (P<0.05). Water quality measurements, including determination of dissolved metals were conducted in an initial attempt to relate any potential toxic effect on wood frog growth and development to specific contaminants.<p>
Results of the laboratory studies strongly suggest that exposure to OSPW and OSPS may adversely affect wood frog growth and survival. However, these findings were not entirely consistent with field observations and results of concurrent mesocosm studies. Further research is therefore needed to fully evaluate the suitability of reclaimed oil sands wetlands to support indigenous amphibian population. Future work should focus on the cumulative effects of water and substrates, as well as the effect of OSPM ageing on acute and chronic toxicity.
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