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In this paper, new polygeneration processes co‐producing electricity, methanol, dimethyl ether (DME), and Fischer–Tropsch (FT) fuels from different feedstock ratios of biomass, natural gas, and nuclear hydrogen generated through a copper‐chlorine (CuCl) cycle are analyzed for operation in Canada to produce transportation fuels. This combination of carbonless heat and a 'carbon neutral' biomass feedstock would contribute to the net reduction in greenhouse gas (GHG) emissions. In Part I of this work, the model for this biomass‐gas‐and‐nuclear‐to‐liquids (BGNTL) process was developed. This work expands on it and evaluates the economic and environmental impacts this plant would have in both Ontario and Alberta based on their local costs and resource availability. The analysis demonstrates that an increase in the ratio of biomass to natural gas in feedstock reduces the emissions of the process but increases the cost of carbon dioxide equivalents (CO2e) avoided. The results show that the BGNTL concept can be an economically attractive way of reducing net transportation sector GHG emissions in both Ontario and Alberta in meaningful quantities. [ABSTRACT FROM AUTHOR]

• Quest CCS facility has been operating since 2015 and has stored upwards of 6 million tonnes of CO2 permanently. • A comprehensive MMV plan is in place to monitor data conformance to model and containment. • 5 key seismic campaigns have occurred during the project and operate phase of the facility with 3 of these campaigns acquiring time-lapse datasets. • Optical Fiber cemented in place has been an effective technology to allow for more data collection at lower cost, lower exposure and higher data repeatability. • Processing enhancements have increased data quality. • Advancements in imaging and interpretation techniques are leading to better understanding of time-lapse seismic utility at quest. • DAS VSP life expectancy is likely coming to an end at quest as the plume grows. Surface seismic is now under assessment. • This paper provides an overview of time-lapse campaigns at quest with the purpose of covering many aspects of the monitoring strategy, data collection and improvements. In August 2015, CO 2 injection commenced at the Quest Carbon Capture and Storage (CCS) Facility located near Fort Saskatchewan, Alberta, Canada. Quest is a fully integrated CCS operation with a capture target of just over one million metric tonnes of CO 2 per year. CO 2 is injected into a deep saline aquifer, the Basal Cambrian Sandstone (BCS), at a depth of about two kilometers below ground. In order to demonstrate containment and conformance of the injected CO 2 , a Measurement, Monitoring and Verification (MMV) plan has been implemented. Multiple domains are monitored as part of the plan, including the atmosphere, biosphere, hydrosphere, geosphere, and wells. Time-lapse seismic methods are utilized primarily for conformance monitoring and secondarily for containment monitoring of the CO 2 plume within the Geosphere domain. These methods currently include 3D surface seismic (SEIS3D), 2D surface seismic (SEIS2D) and 2D multi-azimuth walk-away borehole vertical seismic profiles with distributed acoustic sensing (VSP2D). The first goal of this paper is to summarize the role of seismic, subsurface modeling efforts and the different baseline and monitor datasets that have been acquired at the Quest CCS Facility. The second goal is to describe the current Quest time-lapse strategy. Five key seismic acquisition campaigns have occurred at Quest through the pre- and post-start of injection periods, including an initial SEIS3D acquisition, a pre-injection baseline VSP2D acquisition, and three monitor VSP2D acquisitions. SEIS2D acquisitions have also been acquired as part of two of the most recent monitor campaigns. All campaigns have occurred over the winter season, to facilitate surface access, minimize impact on the land and farming/harvest activities, and to ensure maximum repeatability. Time-lapse seismic methods yield an image of the CO 2 that is injected into the BCS pore space, displacing some of the brine in the saline aquifer. Since the injected CO 2 is more compressible and less dense than brine, the velocity of seismic primary-waves traveling through the BCS is reduced in those places containing CO 2 and remain unchanged elsewhere. Petrophysical data from the injection wells (IWs) were used to calculate the acoustic properties of the BCS. Gassmann fluid substitution was used to model the effect of CO 2 saturation on the expected seismic response. Modeling showed that differences in the seismic images of the BCS obtained before and during CO 2 injection should be seen in two characteristics ways: 1) Travel-times across the BCS increase due to the slower primary-wave velocity inside the BCS. 2) Reflections from the base of the BCS become stronger as the impedance contrast with the underlying granite basement increases. The contrast between the BCS and underlying basement is much larger than between the BCS and the overlying sediments. The large contrast between the BCS and basement produces a prominent reflection which is easily mapped during baseline and monitor surveys and is more practical for amplitude extractions. Modeling also indicated that, while the acoustic changes are sufficient to define the CO 2 front qualitatively, it is unlikely that they can be used to quantify the distribution of CO 2 saturations within the plume. The initial time-lapse seismic strategy called for SEIS3D to be employed after a few years of injection. Borehole distributed acoustic sensing (DAS) VSPs were proposed as a cost-effective and flexible alternative to SEIS3D while injection volumes are small. With the optical fiber cemented in place behind the casing, data can be acquired at any time without suspending injection, something not achievable with conventional VSPs that use retrievable downhole geophone arrays. The effectiveness of VSPs is inherently dependent upon the injection volume, plume offset from the IWs and acquisition geometry. After evaluating the concentric plumes predicted from dynamic modeling results and considering the acquisition logistics at the Quest CCS well sites, a VSP2D program was executed. In 2017 and 2019, SEIS2D was recorded in addition to the VSP2D surveys. Surface geophones were deployed along the VSP2D shot locations, recording a pseudo-3D or cross-spread survey. SEIS2D will be evaluated as another seismic method to potentially monitor CO 2 plume development in the BCS. [ABSTRACT FROM AUTHOR]

Abstract: Alberta is the province with the largest CO2 emissions in Canada, with approximately two-thirds of emissions originating from large stationary sources. Due to the fortuitous association of large CO2 sources with the storage capacity offered by the underlying Alberta basin, it is expected that large-scale CO2 geological storage in Canada will occur in Alberta first, and both levels of governments are contemplating measures to facilitate implementation. A review of the current provincial and federal legislation and regulations presented in this paper indicates that the existing legal and regulatory regime is reasonably sufficient, with some modifications, to accommodate the active injection phase of CO2 capture and storage (CCS) operations, and the early takers of this new technology. However, governments in Alberta and Canada, and likely everywhere, need to address several pressing issues dealing mainly with the CCS post-operational phase. These issues, reviewed in this paper from an Alberta and Canadian perspective, fall into several categories: jurisdictional, property (ownership), regulatory and liability. Because Alberta is a landlocked province, matters relating to CO2 storage under the seabed will not be addressed here except when discussing matters of jurisdiction and CO2 classification. Possible models for post-injection liability transfer to the state are also presented. Although this review is focused on western Canada conditions, the issues are broad enough to be of interest in other jurisdictions, which may also adopt parts of the legal and regulatory framework that is quite well developed in Alberta. [Copyright &y& Elsevier]

• Halite remediation treatment performed on a Quest CCS well to remove halite skin. • Example of halite remediation treatment design for brine aquifer CCS wells. • Halite induced skin and injectivity reductions in CCS wells. The Quest CCS facility (located in Alberta, Canada) is a fully integrated carbon capture, transport and storage facility operated by Shell Canada. It continuously captures and stores about 1.1Mt of CO 2 per year. While the initial injectivity for the Quest CO 2 injection wells was very high, significant injectivity reductions have been observed. As dry CO 2 is injected, water can evaporate from the brine into the CO 2 driving precipitation of halite. Plugging of the perforation tunnel and pore throats in the near wellbore area can cause injectivity damage. One method to remediate halite damage is to inject a water-based fluid to dissolve the halite precipitate. Quest performed the first halite remediation treatment on one of the CO 2 injector wells in 2020. The objective of this paper is to present the design, execution and results of this initial halite remediation treatment. An outline of the design of the halite remediation treatment will be provided. Subsequently the halite remediation treatment as executed in the field will be reviewed including the timing of operations and the pumping pressure and rate data. Finally, to evaluate the effectiveness of the treatment, skin analysis and injectivity trends pre and post remediation treatment shall be presented. [ABSTRACT FROM AUTHOR]

Abstract: This paper will present results of a numerical modelling study on CO2 migration through abandoned wells. Leakage of CO2 through plugged and abandoned wellbores is one of the major concerns for long-term safety and effectiveness of geologic CO2 sequestration. For risk assessment and mitigation, it is not only important to understand and characterize the potential for CO2 leakage through wellbores but also subsequent CO2 migration beyond the primary sequestration reservoir. Subsequent to the leak, CO2 may take a direct path towards the accessible environment or it may migrate in an indirect stair-stepping manner through wellbores/fractures across multiple, shallow permeable strata. In the later case, identification of leak source and application of mitigation strategies may become a challenge. For this study we use data from a site in Alberta, Canada which has reported natural gas leak at surface. Investigations on origin of the gas and potential gas migration path from the original source to the surface at the analog site show that the gas could be moving through multiple wells and across multiple formations. There are multiple wells at the site which were drilled and abandoned without production casing and are completely open between two hydrocarbon bearing zones creating cross-flow across zones through open wellbores. Our study focuses on the deeper formations and potential for leakage for CO2 injected in deeper formation. A complex numerical fluid-flow model is developed for the site in FEHM, LANL’s porous media fluid-flow simulator. The model explicitly accounts for wellbore details such as abandonment plugs, casing, annulus cement, etc. The model was used to perform long-term simulations of CO2 injection and potential migration through abandoned wells. Numerical simulation results show limited migration of CO2 through abandoned wells. Such detailed simulation would be valuable to develop effective abandonment practices as well as mitigation strategies at CO2 sequestration sites. [Copyright &y& Elsevier]

Abstract: Laboratory studies and a number of field pilots have demonstrated that CO2 injection into coal seams has the potential to enhance coalbed methane (CBM) recovery with the added advantage that most of the injected CO2 can be stored permanently in coal. The concept of storing CO2 in geologic formations as a safe and effective greenhouse gas mitigation option requires public and regulatory acceptance. In this context it is important to develop a good understanding of the reservoir performance, uncertainties and the risks that are associated with geological storage. The paper presented refers to the sources of uncertainty involved in CO2 storage performance assessment in coalbed methane reservoirs and demonstrates their significance using extensive digital well log data representing the Manville coals in Alberta, Canada. The spatial variability of the reservoir properties was captured through geostatistical analysis, and sequential Gaussian simulations of these provided multiple realisations for the reservoir simulator inputs. A number of CO2 injection scenarios with variable matrix swelling coefficients were evaluated using a 2D reservoir model and spatially distributed realisations of total net thickness and permeability. [Copyright &y& Elsevier]

In order to better understand factors affecting greenhouse gas (GHG) emissions in Canadian agroforestry systems, we conducted a laboratory incubation study to assess N2O, CO2 and CH4 emissions from soils in response to land use (forestland vs. cropland) and agroforestry system type (hedgerow vs. shelterbelt) in central Alberta, Canada. Emissions of N2O were lower in soils from forestland than cropland, and forest soils acted as a net sink of atmospheric CH4 while cropland soils were weak sources of CH4. However, the forest soil had higher CO2 emission rates than the cropland soil within both agroforestry systems. Soil CH4 oxidation was higher in soil from hedgerow (consisted of natural forest vegetation) than from shelterbelt system (planted forest vegetation), while the former also had lower N2O emissions. Overall, soil CO2 emissions were significantly higher from hedgerow than from shelterbelt systems. Emissions of N2O were positively related with gross nitrification rates and soil pH, and negatively related with gross N immobilization rates. The CO2 emissions were positively related with water‐soluble organic C contents, while CH4 emissions were positively related with clay content, but negatively with gross N immobilization rates and soil organic C content. The global warming potential was higher in forestland soil than in cropland soil within agroforestry systems, and higher in forestland soil of the hedgerow compared to that in shelterbelts. Our results suggest that we need to select land uses or agroforestry systems that have a higher potential of mitigating GHG emissions from soils. [ABSTRACT FROM AUTHOR]

A 2-year field study was conducted to compare the effect of wheat straw, its biochar, and wheat straw plus biochar addition on soil fluxes of CO2, CH4, and N2O during the growing season, and soil properties and crop yield in a Black Chernozemic soil planted to barley (Hordeum vulgare L.) in central Alberta, Canada. The objective was to assess the benefit of applying biochar instead of its feedstock, wheat straw, in improving environmental sustainability. Biochar addition did not affect soil CH4 oxidation, but decreased CO2 and N2O emissions as compared with both wheat straw applied alone and wheat straw and biochar applied together in 2010 and 2011 (p < 0.001), and resulted in a lower global warming potential, indicating that the biochar was effective in mitigating greenhouse gas (GHG) emission from the agricultural soil, as a result of biochar suppressing soil microbial activity and reducing soil N availability. Biochar application reduced N2O emission over 2 years, indicating its longer-term impact. Biochar application alone increased barley yield by 9.9 to 20.4% as compared to the other three treatments, thus reducing yield-scaled greenhouse gas emission intensity by 27.2 to 50.9% (p = 0.013 for the control and p < 0.001 for both wheat straw–amended treatments), with an average reduction of 3.43 t CO2-eq t−1 grain. The application of both wheat straw and its biochar reduced the temperature sensitivity of soil CO2 emission (Q10, p < 0.001), but the application of wheat straw or its biochar alone did not affect Q10, indicating that biochar application reduces the sensitivity to temperature changes of the decomposition of the new organic matter added to the soil. We conclude that (1) the application of wheat straw–derived biochar was preferred to raw wheat straw in mitigating GHG emission and (2) biochar can be an effective management strategy for properly handling crop residues in sustainable agriculture. [ABSTRACT FROM AUTHOR]

During mining topsoil is salvaged and stockpiled until ready for reclamation, stockpiling can have detrimental effects on seed viability and soil quality. Research has assessed effects of salvage and placement depth of forest topsoil on plant community establishment, with little work on effects of storage, particularly in the boreal forest. Our research assessed boreal forest topsoil storage methods to determine effects on soil chemical and physical properties, native seed viability and germination and rhizome viability and emergence. Factors were topsoil stockpiling length, stockpile size, season of construction and soil texture. Four replicates of large and small stockpiles were constructed in the mineable oil sands, in northeastern Alberta. During construction seeds and rhizomes from a variety of native boreal plant species were buried within large (0.05, 1.0, 2.0, 4.0, 6.0 m) and small (0.05, 1.0, 3.0 m) stockpiles. Soil gas probes were installed at similar depths as seed and rhizomes were placed. Seeds and rhizomes were extracted eight months and sixteen months after construction; during that time soil samples were collected for various chemical analyses. Irrespective of stockpile size, the majority of species seeds and rhizomes buried below 1 m lost viability and did not germinate after eight months. Anaerobic soil conditions developed soon after construction and persisted at depths below 1.0 m in large stockpiles, and over time anaerobic conditions developed in smaller stockpiles. Only seeds of Geranium bicknellii and Dracocephalum parviflorum had a high survival rate in stockpiles; both species have hard seed coats and are physically dormant. Various soil nutrients increased in concentrations in their soluble forms after stockpiling. Direct placement of topsoil is a preferred soil handling technique; however, if topsoil has to be stockpiled increasing the surface area of stockpiles will help preserve some seed and rhizome viability. [ABSTRACT FROM AUTHOR]

ABSTRACT Common shot ray tracing and finite difference seismic modelling experiments were undertaken to evaluate variations in the seismic response of the Devonian Redwater reef in the Alberta Basin, Canada after replacement of native pore waters in the upper rim of the reef with CO2. This part of the reef is being evaluated for a CO2 storage project. The input geological model was based on well data and the interpretation of depth-converted, reprocessed 2D seismic data in the area. Pre-stack depth migration of the ray traced and finite difference synthetic data demonstrate similar seismic attributes for the Mannville, Nisku, Ireton, Cooking Lake, and Beaverhill Lake formations and clear terminations of the Upper Leduc and Middle Leduc events at the reef margin. Higher amplitudes at the base of Upper-Leduc member are evident near the reef margin due to the higher porosity of the foreslope facies in the reef rim compared to the tidal flat lagoonal facies within the central region of the reef. Time-lapse seismic analysis exhibits an amplitude difference of about 14% for Leduc reflections before and after CO2 saturation and a travel-time delay through the reservoir of 1.6 ms. Both the ray tracing and finite difference approaches yielded similar results but, for this particular model, the latter provided more precise imaging of the reef margin. From the numerical study we conclude that time-lapse surface seismic surveys should be effective in monitoring the location of the CO2 plume in the Upper Leduc Formation of the Redwater reef, although the differences in the results between the two modelling approaches are of similar order to the effects of the CO2 fluid replacement itself. [ABSTRACT FROM AUTHOR]