Oil sand deposits are found at three depths; shallow, intermediate, and deep. Shallow deposits are processed by surface mining while deep deposits are processed using thermal extraction methods. There are currently no production methods to extract oil sand at intermediate depths. The motivation for this research is to demonstrate the technical applicability of methods to access oil sand that is too shallow for thermal extraction methods and too deep for economical surface mining. This work consisted of developing a system concept as a method for accessing, fragmenting, and removing oil sand at intermediate depths. A technical analysis and a cost estimate were also performed. In addition, the applicability of a comparative methodology was demonstrated with case studies. A key gap in the understanding of how to implement the system concept is tooling design and power requirements for fragmenting oil sand and interburden; and so a set of laboratory experiments was conducted to investigate the power required to cut oil sand. Oil sand blocks were formed from oil sand samples for the experiments. These blocks underwent various tests to examine their characteristics. Tests included: shear testing, extraction testing, porosity measurements, and scanning electron microscopy. Lab-scale experiments were conducted in dry, wet, and frozen conditions in support of the fragmentation aspect of the system concept. Thermal imaging was used to qualitatively view temperature variation during the testing process and cutter wear was viewed using a digital microscope. Results were compared against a steady-state cutting model with recommendations for future work.

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No description available.

No description available.

A plume of process-affected groundwater was identified in a shallow sand aquifer adjacent to a tailings impoundment at Syncrude Canada Ltd. Quantitative and qualitative Naphthenic Acid (NA) analyses were performed on groundwater samples to investigate NA fate and transport properties in the subsurface. Analysis of dissolved organic and inorganic components was undertaken to identify, quantify and assess the mobility of other dissolved components of environmental significance. NAs at concentrations up to 87 mg/L were found to represent the major contributor to aquatic toxicity. Attenuation of NAs by biodegradation is not observed based on screening techniques developed to date. Retardation of NAs observed at the field scale, is consistent with weak sorption observed in the laboratory by other authors. Concentrations of ammonium approached 4 mg/L in the plume, however mobility is limited by cation exchange. Aromatics and trace metals are present in low quantities (i. e. <10 ??g/L) and are only detected in groundwater immediately adjacent to the toe of the tailings impoundment. Cl and Na are found at concentrations of up 282 and 579 mg/L respectively. Dissolved oxygen is typically < 1 mg/L within the plume, while redox indicators Mn(II), Fe(II) and methane are detected between <0. 1 - 2. 6, 0. 2 - 3. 5 and <0. 1 - 2. 1 mg/L respectively within the plume. Solid phase geochemistry, determined through solid phase extractions, was coupled with aqueous geochemistry and reactive transport modeling to identify the dominant geochemical processes occurring within the plume. Based on scenarios evaluated using reactive transport modeling, the most likely origin for the presently observed, weakly reducing conditions in the plume appears to be the presence of a small amount of disssolved, degradable organic carbon. The dominant terminal electron acceptors appear to be Fe(III) and Mn(III/IV) in the plume core and dissolved oxygen at the plume fringe. Dissolved Fe and Mn are observed to enter the domain at the upgradient boundary at maximal concentrations of 4. 2 and 0. 7 mg/L respectively. Trace metal geochemistry of the aquifer material was also assessed using solid phase extractions. The potential for trace metal release via reductive dissolution of the native geologic material is considered minimal in this case, based on the weakly reducing nature of the plume and a lack of excessive trace metal content in the aquifer material.

Albertas oil sands are located in the boreal forest where surface mining disturbs huge tracts of land. One such area, Syncrude Canada Ltd.s Mildred Lake mine, contains waste overburden (OB) piles which can be saline and sodic (SSOB). The objectives of this research were to 1) determine SSOB material impacts on planted tree root distributions, 2) quantify root activity to identify plant species growing at depth, and 3) document coarse woody root structure for planted trees. Root distributions for three mixedwood stands on reclaimed OB in relation to electrical conductivity (EC) and sodium absorption ratio (SAR) were examined using soil cores. Root distributions followed a similar pattern with soil depth as those from undisturbed boreal forest stands and appeared unaffected by the SSOB at this stage; however, future monitoring will be required as the stands mature. Root activity was assessed for jack pine (jP) and white spruce (wS) stands on tailings sand (TS) and OB using a strontium (Sr) chloride tracer. Understory and tree foliage was collected prior to and after application to measure Sr concentration in the control, broadcast, and depth treatments. A small proportion of roots grew in the OB material regardless of its chemical properties. Results from the Sr tracer study suggested that these roots were probably from the clover, sow thistle, and grasses. Planted trees showed little to no change in Sr tissue content suggesting that there were little to no roots in the treatment zones, the understory species out-competed the trees for Sr accessibility, or the tracer was diluted in the tree biomass to undetectable levels. Root systems of planted jP trees older than 10 years and older than 20 years on TS and OB were excavated and the number and diameter of lateral roots, the degree of kinking and coiling, and the presence of a taproot were recorded. Excavated trees showed poor taproot development on 70% of the trees and numerous root deformities, suggesting that more emphasis is needed in correct planting techniques and good planting stock to ensure proper root development. Roots are critical components of boreal forest ecosystems; without healthy root systems productivity may decline, stands may be susceptible to windthrow, and general forest health may suffer.

A plume of process-affected groundwater was identified in a shallow sand aquifer adjacent to a tailings impoundment at Syncrude Canada Ltd. Quantitative and qualitative Naphthenic Acid (NA) analyses were performed on groundwater samples to investigate NA fate and transport properties in the subsurface. Analysis of dissolved organic and inorganic components was undertaken to identify, quantify and assess the mobility of other dissolved components of environmental significance. NAs at concentrations up to 87 mg/L were found to represent the major contributor to aquatic toxicity. Attenuation of NAs by biodegradation is not observed based on screening techniques developed to date. Retardation of NAs observed at the field scale, is consistent with weak sorption observed in the laboratory by other authors. Concentrations of ammonium approached 4 mg/L in the plume, however mobility is limited by cation exchange. Aromatics and trace metals are present in low quantities (i. e. <10 µg/L) and are only detected in groundwater immediately adjacent to the toe of the tailings impoundment. Cl and Na are found at concentrations of up 282 and 579 mg/L respectively. Dissolved oxygen is typically < 1 mg/L within the plume, while redox indicators Mn(II), Fe(II) and methane are detected between <0. 1 - 2. 6, 0. 2 - 3. 5 and <0. 1 - 2. 1 mg/L respectively within the plume. Solid phase geochemistry, determined through solid phase extractions, was coupled with aqueous geochemistry and reactive transport modeling to identify the dominant geochemical processes occurring within the plume. Based on scenarios evaluated using reactive transport modeling, the most likely origin for the presently observed, weakly reducing conditions in the plume appears to be the presence of a small amount of disssolved, degradable organic carbon. The dominant terminal electron acceptors appear to be Fe(III) and Mn(III/IV) in the plume core and dissolved oxygen at the plume fringe. Dissolved Fe and Mn are observed to enter the domain at the upgradient boundary at maximal concentrations of 4. 2 and 0. 7 mg/L respectively. Trace metal geochemistry of the aquifer material was also assessed using solid phase extractions. The potential for trace metal release via reductive dissolution of the native geologic material is considered minimal in this case, based on the weakly reducing nature of the plume and a lack of excessive trace metal content in the aquifer material.

Albertas oil sands are located in the boreal forest where surface mining disturbs huge tracts of land. One such area, Syncrude Canada Ltd.s Mildred Lake mine, contains waste overburden (OB) piles which can be saline and sodic (SSOB). The objectives of this research were to 1) determine SSOB material impacts on planted tree root distributions, 2) quantify root activity to identify plant species growing at depth, and 3) document coarse woody root structure for planted trees. Root distributions for three mixedwood stands on reclaimed OB in relation to electrical conductivity (EC) and sodium absorption ratio (SAR) were examined using soil cores. Root distributions followed a similar pattern with soil depth as those from undisturbed boreal forest stands and appeared unaffected by the SSOB at this stage; however, future monitoring will be required as the stands mature. Root activity was assessed for jack pine (jP) and white spruce (wS) stands on tailings sand (TS) and OB using a strontium (Sr) chloride tracer. Understory and tree foliage was collected prior to and after application to measure Sr concentration in the control, broadcast, and depth treatments. A small proportion of roots grew in the OB material regardless of its chemical properties. Results from the Sr tracer study suggested that these roots were probably from the clover, sow thistle, and grasses. Planted trees showed little to no change in Sr tissue content suggesting that there were little to no roots in the treatment zones, the understory species out-competed the trees for Sr accessibility, or the tracer was diluted in the tree biomass to undetectable levels. Root systems of planted jP trees older than 10 years and older than 20 years on TS and OB were excavated and the number and diameter of lateral roots, the degree of kinking and coiling, and the presence of a taproot were recorded. Excavated trees showed poor taproot development on 70% of the trees and numerous root deformities, suggesting that more emphasis is needed in correct planting techniques and good planting stock to ensure proper root development. Roots are critical components of boreal forest ecosystems; without healthy root systems productivity may decline, stands may be susceptible to windthrow, and general forest health may suffer.

No description available.

No description available.