The impact of reclamation cover depth on the performance of reclaimed shale overburden at an oil sands mine in Northern Alberta, Canada

Abstract The design of reclamation soil covers at oil sands mines in northern Alberta, Canada, has been conventionally based on the calibration of soil–vegetation–atmosphere transfer (SVAT) models against field monitoring observations collected over several years, followed by simulations of long-term performance using historical climate data. This paper evaluates the long-term water balances for reclamation covers on two oil sands landforms and three natural coarse-textured forest soil profiles using both historical climate data and future climate projections. Twenty-first century daily precipitation and temperature data from CanESM2 were downscaled based on three representative concentration pathways (RCPs) employing a stochastic weather generator [Long Ashton Research Station Weather Generator (LARS-WG)]. Relative humidity, wind speed, and net radiation were downscaled using the delta change method. Downscaled precipitation and estimated potential evapotranspiration were used as inputs to simulate soil water dynamics using physically based models. Probability distributions of growing season (April–October) actual evapotranspiration (AET) and net percolation (NP) for the baseline and future periods show that AET and NP at all sites are expected to increase throughout the twenty-first century regardless of RCP, time period, and soil profile. Greater increases in AET and NP are projected toward the end of the twenty-first century. The increases in future NP at the two reclamation covers are larger (as a percentage increase) than at most of the natural sites. Increases in NP will result in greater water yield to surface water and may accelerate the rate at which chemical constituents contained within mine waste are released to downstream receptors, suggesting these potential changes need to be considered in mine closure designs.

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Breccia interlayer effects on steam-assisted gravity drainage performance: experimental and numerical study

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-021-01320-0 ◽

2021 ◽

Author(s):

Qichen Zhang ◽

Xiaodong Kang ◽

Huiqing Liu ◽

Xiaohu Dong ◽

Jian Wang

Keyword(s):

Numerical Simulation ◽

Oil Recovery ◽

Oil Sands ◽

Numerical Study ◽

Middle Part ◽

Experimental Results ◽

Production Performance ◽

Peak Oil ◽

Steam Chamber ◽

The Impact

AbstractCurrently, the reservoir heterogeneity is a serious challenge for developing oil sands with SAGD method. Nexen’s Long Lake SAGD project reported that breccia interlayer was widely distributed in lower and middle part of reservoir, impeding the steam chamber expansion and heated oil drainage. In this paper, two physical experiments were conducted to study the impact of breccia interlayer on development of steam chamber and production performance. Then, a laboratory scale numerical simulation model was established and a history match was conducted based on the 3D experimental results. Finally, the sensitivity analysis of thickness and permeability of breccia layer was performed. The influence mechanism of breccia layer on SAGD performance was analyzed by comparing the temperature profile of steam chamber and production dynamics. The experimental results indicate that the existence of breccia interlayer causes a thinner steam chamber profile and longer time to reach the peak oil rate. And, the ultimate oil recovery reduced 15.8% due to much oil stuck in breccia interlayer areas. The numerical simulation results show that a lower permeability in breccia layer area has a serious adverse impact on oil recovery if the thickness of breccia layer is larger, whereas the effect of permeability on SAGD performance is limited when the breccia layer is thinner. Besides, a thicker breccia layer can increase the time required to reach the peak oil rate, but has a little impact on the ultimate oil recovery.

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Modelling plant water relations and net primary productivity as affected by reclamation cover depth in reclaimed forestlands of northern Alberta

Plant and Soil ◽

10.1007/s11104-019-04363-9 ◽

2019 ◽

Vol 446 (1-2) ◽

pp. 627-654 ◽

Cited By ~ 1

Author(s):

N. P. Y. Welegedara ◽

R. F. Grant ◽

Sylvie A. Quideau ◽

Simon M. Landhäusser ◽

Morgane Merlin ◽

...

Keyword(s):

Water Relations ◽

Primary Productivity ◽

Net Primary Productivity ◽

Plant Water Relations ◽

Plant Water ◽

Cover Depth ◽

Northern Alberta

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Efficient maintenance method for water supply facilities focused on the carbonation of concrete

Water Practice & Technology ◽

10.2166/wpt.2019.004 ◽

2019 ◽

Vol 14 (1) ◽

pp. 178-188

Author(s):

Masaki Fujita ◽

Shoichi Iwasaki ◽

Keinosuke Inoko ◽

Kenji Hayashi

Keyword(s):

Water Supply ◽

Environmental Conditions ◽

Surface Coating ◽

Inhibitory Effect ◽

Concrete Cover ◽

Cover Depth ◽

Concrete Deterioration ◽

Inner Surface ◽

The Impact ◽

Published Research

Abstract In water supply facilities such as distribution reservoirs, the inner surface of reinforced concrete (RC) tanks is often coated with resin paint or the concrete cover depth is increased to protect the concrete from surface deterioration. However, there is little published research on carbonation – one of the main causes of concrete deterioration – in relation to RC tanks, leaving room for improvement with regard to methods for preventing surface deterioration. This study discusses the impact of surface coating and environmental conditions on the carbonation rate of concrete based on a survey of the present state of RC tanks of the Sapporo Waterworks Bureau. Coating was found to have an inhibitory effect on carbonation. Because the carbonation rate of concrete used for the inside and outside of RC tanks was slow, the sufficient concrete cover depth to protect rebar from carbonation while in service was found to be 75 mm for RC tanks without coating.

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“Fighting the Same Old Battle”: Obscured Oil Sands Entanglements in Press Coverage of Indigenous Resistance in the Winter of 1983

Canadian Journal of Communication ◽

10.22230/cjc.2018v43n1a3311 ◽

2018 ◽

Vol 43 (1) ◽

Author(s):

Patricia H. Audette-Longo

Keyword(s):

Critical Discourse Analysis ◽

Oil Sands ◽

Healthcare Access ◽

Critical Discourse ◽

Newspaper Coverage ◽

Press Coverage ◽

Indigenous Resistance ◽

Fort Mcmurray ◽

Energy Politics ◽

Northern Alberta

Background This article examines a week-long road blockade that took place in northern Alberta in January, 1983, organized by members of the Fort McKay First Nation and the Fort McKay Métis Community. The communities leveraged their blockade against a logging company, expanding the conversation to demand compensation, tougher oil sands pollution management, and better healthcare access. Analysis A critical discourse analysis of newspaper coverage of the blockade in the local Fort McMurray Today and the provincial Edmonton Journal shows how links between the blockade and broader oil sands politics were minimized. Conclusions and implications The article closes with considerations for contemporary journalistic practices of covering oil development, energy politics, and Indigenous resistance.Contexte Cet article examine le blocus d’une semaine organisé par la Première Nation de Fort McKay et la Communauté Métis de Fort McKay au nord de l’Alberta en janvier 1983. Ces communautés ont mis à profit leur blocus contre une entreprise forestière pour demander des compensations, une gestion plus stricte de la pollution provenant des sables bitumineux et un meilleur accès aux soins.Analyse Une analyse critique du discours utilisé pour parler du blocus dans les journaux, au niveau local dans le Fort McMurray Today et au niveau provincial dans le Edmonton Journal, démontre comment les liens entre le blocus et les politiques plus larges des sables bitumineux ont été minimisés.Conclusion et implications L’article conclut avec des considérations pour les pratiques journalistiques contemporaines dans la couverture du développement pétrolier, politiques énergétiques et résistance autochtone.

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The Use of Carbon and Nitrogen Stable Isotope Analysis to Characterize Food Web Changes in Aquatic Systems for Reclamation of Oil Sands Process-Affected Materials

Water Quality Research Journal ◽

10.2166/wqrj.2009.032 ◽

2009 ◽

Vol 44 (4) ◽

pp. 313-322 ◽

Cited By ~ 4

Author(s):

Monalisa Elshayeb ◽

Michael D. MacKinnon ◽

D. George Dixon ◽

Michael Power

Keyword(s):

Food Web ◽

Oil Sands ◽

Isotope Analysis ◽

Naphthenic Acid ◽

Carbon Sources ◽

Nitrogen Isotope ◽

Isotopic Signatures ◽

Carbon And Nitrogen ◽

Aquatic Food ◽

Northern Alberta

Abstract One strategy for reclamation of oil sands leases in northern Alberta is the construction of lakes and wetlands by capping oil sands process-affected material (OSPM) with water. To assess this approach, experimental sites containing a range of OSPM have been constructed to monitor the evolution of the resulting aquatic habitats. Stable isotopes of carbon and nitrogen were used to assess the effects of OSPM on aquatic food webs. Carbon and nitrogen isotopic signatures of sediment, dissolved inorganic and organic carbon, particulate organic matter, periphyton, plants, plankton, aquatic invertebrates, and fish were used to assess differences related to the naphthenic acid (NA) concentration in OSPM and reference sites. NAs are a principal contaminant of concern in OSPM. Sites were grouped into low (0 to 4 mg/L), medium (4 to 15 mg/L), and high (>15 mg/L) NA concentrations. There were no significant differences in food web area or length among the three NA groupings. In most cases, carbon isotope analyses of samples from low, medium, and high NA concentration sites were not significantly different, suggesting that OSPM is not a significant contributor to food web carbon sources. Significant differences were found in nitrogen isotope signatures between low, medium, and high NA sites. Ammonia from OSPM is suggested as the main contributor to δ15N enrichment.

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