The traditional method of repairing damaged roads in Atlantic Canada has been to place a hot mix asphalt overlay over the existing road. Though this method provides a new, smooth wearing surface to drive on, it is merely a short term fix. With time, the cracks in the original pavement will reflect to the surface of the new pavement, resulting in failure of the overlay. An alternative option gaining more prominence is the use of a Full Depth Reclamation (FDR) technique, which involves pulverizing the flexible pavement, along with a portion of the underlying layer. This material is then stabilized and recompacted to produce a new base layer that is free of damage. Though FDR has been used for a number of years, there are still problems with variability in the strength of the materials in some projects. It is hypothesized that some of these problems are due to variability and poor quality in the reclaimed materials. It is believed that current pulverization methods contribute to the variability being observed in these materials. Two FDR projects employing different pulverization control methods were studied to examine how the consistency of the reclaimed materials can be improved through the use of a Ground Penetrating Radar (GPR) survey to map the variability in the depth of the pavement. Controlling the thickness ratio of asphalt concrete to granular base materials being pulverized was shown to improve the consistency of materials, properties, and performance. The second phase of this research project studied how improving the gradation of the reclaimed materials with the addition of a crusher dust might result in improved performance of stabilized base materials, in this case stabilized with expanded asphalt. The effect of construction variability on the improved materials was also studied by varying both the moisture content, and asphalt content from optimum conditions, as might be expected during construction. Results indicated that the quality of the stabilized FDR materials can be significantly improved by bringing the material gradation closer to the theoretical maximum density gradation. The performance of the stabilized materials can be affected by both the mixing moisture content, and the asphalt content used during stabilization. This suggests that effective quality control, and stricter specifications on the constructed product would result in more reliable, effective FDR pavements. / A study on the control of the consistency of pulverized FDR materials, as well as a study examining how to improve the performance of these pulverized materials.

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The mode of propagation of a plant species may influence its success in recolonizing a successional forest following agricultural disturbance. It is hypothesized that plants with animal-borne or broadcast-dispersed seed will successfully recolonize, while plants which rely upon vegetative propagules may not repopulate the disturbed area. This hypothesis was tested by comparing vascular, herbaceous plant communities of two forests (one old-growth and one successional) in east-central Indiana. Populations of vascular, herbaceous plant species were inventoried in both forests, and the soil characteristics (organic matter and pH) of both areas were analyzed. The two forests had similar soil organic matter profiles, but the pH of the disturbed forest was significantly lower than that of the undisturbed area. Most vegetatively-propagated plant species were, as predicted, significantly more abundant in the undisturbed forest; the disturbed area had been effectively recolonized by animal-borne and broadcast-dispersed seed plants. This perspective has implications for long-term management of east-central Indiana forests. / Department of Natural Resources and Environmental Management

Due to the nature of the regional geology and the bitumen extraction process, the post-mined landscape of Canada’s oil sands region will have a much higher concentration of dissolved salts than it did prior to mining. As a result, naturally saline wetlands may constitute appropriate reclamation targets and knowledge of saline wetland hydrology can provide important clues to their form and function. Furthermore, the presence of saline discharge features in the Athabasca oil sands region (AOSR) provides an opportunity to study more closely the nature of groundwater flow in a region of considerable hydrogeologic complexity, including the origin and flow history of brines and the link between springs, subsurface wastewater containment and surface water quality. A low-flow saline-spring fen peatland located adjacent to a proposed in-situ oil extraction facility was examined south of the oil sands hub of Fort McMurray, Alberta. Hydrologically disconnected from underlying Devonian deposits that are a typical source of salinity, a saline groundwater plume originating from a Lower Cretaceous aquifer (the Grand Rapids Formation) was identified as a likely source for the accumulation of Na+ (mean of 6,949 mg L-1) and Cl- (mean of 13,766 mg L-1) in fen groundwater. Considerable spatial variability in ground and surface water salinity was observed, with the concentration of dissolved salts decreasing by an order of magnitude in the direction of flow. A sharp decrease in near-surface salinity was found along the entire perimeter between the fen and adjacent freshwater wetlands. Patterns in deep groundwater flux were difficult to interpret due to possible inaccuracies associated with the piezometer network (e.g., time-lag errors in low hydraulic conductivity substrates), and rates of groundwater input were estimated to be small (< 1 mm over a season) due to the low conductivity of the underlying mineral till (5.5x10-7 cm s-1). Water table dynamics were exaggerated in response to wetting and drying for both study seasons and the fen’s small subsurface storage capacity was readily exceeded under periods of sustained rainfall. The large pond network functioned as an effective transmitter of surface water during periods of high water table but was a sink of groundwater during dry periods due to high rates of evaporation. Despite flooding conditions observed in 2012, groundwater exchange between the fen and adjacent wetlands was low and the rough microtopography worked to detain surface waters and restrict runoff in the fen’s lower reaches. Together these mechanisms worked to isolate the saline fen and restrict the flux of saline waters into the surrounding landscape. Elevated concentrations of dissolved salts in nearby wetland and river systems indicates that influence of saline discharge is not solely restricted to the region’s major river systems. The flux of salt from saline wetlands may play an important role in the overall water quality of groundwater and receiving water bodies (e.g., nearby river systems). The geochemical signature of fen groundwater points to halite as a source of salinity, as indicated by Cl-/Br- ratios in excess of 7,000. This is in contrast to what has been observed for regional formation brines that are typically related to evaporated seawater. Isotopic evidence and relatively low salinities compared to springs in the Wood Buffalo region suggests that fen discharge water may be significantly diluted as a result of mixing with freshwater sources. The contribution of evaporite to discharge water may be coming from somewhere deeper and further south in the basin. This has important implications for the disposal of wastewater by deep well injection, as disposal zones may be hydrologically linked to near-surface aquifers and discharge features well beyond the immediate production and storage area.

This project is a pilot study to assess the viability of transplantation as a technique to establish reindeer lichens on reclaimed areas of oil sands surface mines in the Athabasca region of Alberta. There were two components to this study: a) a lichen transplant trial, where I investigated which commonly available substrates found in reclaimed forest sites would promote the best lichen fragment survival and vigour for a lichen ‘seeding’ program; and b) a diversity assessment of the reclaimed site to compare the existing cryptogam community with the expected community for the target ecosite based on published descriptions from the surrounding native forests and documented chronosequences for terrestrial lichen communities. In July 2009, Cladonia mitis was transplanted into 54 plots on three sites that were planted with jack pine or spruce 12 or 24 years ago, respectively, on the Suncor Millenium/Steepbank Mine (Suncor Mine). This trial was designed to investigate possible short-term indicators of successful lichen establishment and the effect of substrate (moss, litter, or soil) on the establishment of transplanted lichen thallus fragments. The indicators of lichen establishment evaluated were vigour, movement from plots, photographic areal cover, and microscopic growth (hyphal growth, annual growth and lateral branching). After two growing seasons, the effect of substrate on lichen transplant survival varied by site; there was no significant difference in lichen fragment retention in plots by substrate on the 24-year old sites, but median fragment retention was significantly higher on moss and litter substrates than soil on the 12-year old site. There was also no significant difference in fragment vigour between substrates on each site, except on the south-facing 24-year-old forest site where average vigour was significantly higher on moss plots than on soil plots. Photographic areal measurement is not recommended as a short-term lichen establishment monitoring tool for transplanted fragments based on the difficulties encountered using the method for this trial. Forty-one percent of the fragments collected for microscopic assessment after the first growing season had grown hyphae, 23 percent of the fragments collected during September 2009 and September 2010 had formed apothecia, and 31 percent of the fragments collected in September 2010 had grown lateral branches. The results of the biodiversity assessment were compared with the successional communities previously described for spruce- and pine-lichen boreal forests. There were no lichens found on the 12-year-old site, though the cup lichens were common to abundant on the 24-year-old sites, which is consistent with the cryptogammic community expected for a regenerating natural site of that age. Cladonia mitis was also present but rare to uncommon on the 24-year-old site, while Cladonia stellaris, Cladonia rangiferina and Cladonia stygia that, together with C. mitis, are indicative of the al and c1 ecosites of the Central Mixedwood Boreal forest, were not present. / Graduate

The aspiration of this work was a call for justice for the Sons of Freedom Doukhobors - past, present and future. Sharing a Sons of Freedom identity, I worked within heritage; a heritage with deep cultural and spiritual roots that has encountered and responded to injustices through resistance and eventual assimilation into Canadian society. Justice as the primary motivation of this study is contingent upon hospitality or in the same breath deconstruction, derived from the work of Jacques Derrida and John Caputo. Hospitality is the theoretical, ethical and methodological pulse of this study and made possible a collective re-contextualizing of identity. Hospitality is an open and excessive welcome principled upon unconditional inclusion yet faced with an inevitable interplay of exclusion in all inclusion. The parameters of this study situated within the context of a Sons of Freedom heritage determined the welcome - although broad - was also specific and conditional. Working within an ethic of hospitality involved working with others in co-created relational spaces. Being in shared spaces generated memories, stories, songs and perspectives impassioned by sadness, anger, hope, ideas and intentions to sustain and keep identity on the move. The role of researcher and participant, or host and guest, was often disrupted as the roles became interchangeable. The blurred roles fostered spaces of sharing, trust, care and a sense of togetherness that “We are in this together.” Walking-alongside became a creative site for mobilizing counter narratives and critical interpretations to re-represent identity and on-going becoming. Justice, key to deconstruction and to this study, opened up the possibility of claiming identity as opposed to escaping or being burdened with an identity laden with stigma and shame. / Graduate / 0344 / 0998 / ahnab@shaw.ca

Research assessed early stages of calcareous soil reclamation along the TMX-Anchor Loop pipeline through Jasper National Park. Calcareous soils are low in nutrients and highly prone to erosion after disturbances. Four sites were established in each of five calcareous soils, and divided into three pipeline right-of-way areas; work, trench and spoil. Ten amendment treatments, established within each right-of-way areaincluded a control and combinations of wood chips, fertilizer and compost with some plots having amendments incorporated. Wood chip treatments decreased availability of soil nutrients, with small plants contributing to high vegetation densities and low cover. Compost treatments increased soil nutrients and aided large plant establishment, creating lower plant densities and higher cover. Light application rates were most successful, with higher native plant densities and cover in relation to heavy application rates, which encouraged robust non-native plants. Pipeline right-of-way areas had no overall impact on early reclamation success. / Land Reclamation and Remediation

The vegetation rehabilitation of iron ore waste dumps and industrial site waste is an important part of completion criteria for mining, especially as legislation requirements increase. There are limited guidelines currently available for companies to achieve these rehabilitation goals and those that exist tend to be anecdotally rather than scientifically based. Some scientific studies have been carried out using topsoil and seeding as restoration treatments, but very little information is available on their usefulness in the arid zone. This study assesses the outcomes of a range of rehabilitation projects carried out in the Middleback Ranges, South Australia. / For historical sites, data was collected by line transects and point quarter (i.e they were quantitative and repeatable even if the design was historical). These projects were not originally designed for scientific purposes, so are not controlled or replicated. Therefore data was collected in a descriptive, non-experimental and interpretive manner. Similar data was also gathered, at nearby reference sites (unmined areas) of similar landform to gauge the success of the revegetation. / The historical study showed that long-term monitoring using scientific protocol is the only reliable method of gauging rehabilitation success and may be crucial in deciding completion criteria in the future, whereas ad-hoc restoration with no written records is of limited use to restoration science. However, the historical study did provide an opportunity to discuss rehabilitation success over a longer period than would normally be included in a short study. / A controlled and replicated field - based experiment testing both topsoil and seeding treatments was designed for the Iron Baron mine site, in the Middleback Ranges. A second experiment testing only the seeding treatment was carried out at the Whyalla Steelworks. At Iron Baron mine site ten contour terraces were built which provided 20 transects, allowing five replicates of treatments: topsoil and seed; topsoil and no seed; no topsoil and seed; and no topsoil and no seed. At the Whyalla Steelworks ten transects were furrowed, allowing five replicates of topsoil with seed and five of topsoil with no seed. At both experimental sites line transects were conducted which measured percentage cover, density and canopy volume of emerging vegetation cover. Each measure of vegetation response from each experiment was modelled using spatial analysis of mixed models (SAMM). / The experimental trials confirmed the hypothesis that there is a significant difference in revegetation using topsoil and seeding treatments. Topsoil with seed provided the most superior result. Increases in cover, density, canopy volume and biodiversity proved that both these treatments were effective for the arid zone. Should only one treatment be possible then topsoiling is the more effective option. / Thesis (MAppSc(EnvironmentRecreationMg))--University of South Australia, 2003.