Vakarų Lietuvoje aptikus padidėjusį šilumos srautą, imta domėtis geoterminės energetikos perspektyvomis. Išmatavus geoterminės anomalijos zonos savybes pastebėta, kad šioje zonoje vyraujantis šilumos srautas yra dvigubai didesnis, nei likusioje Lietuvos teritorijoje ir yra dvigubai didesnis už vidutinį rytų Europos šilumos srautą, o aukštesnės nei 150 ºC temperatūros yra pasiekiamos kristalinio pamato uolienose. Pirminiai geoterminės anomalijos parametrai yra nustatomi geofizinių ir geocheminių metodų pagalba. Kiti parametrai – gręžinio eksploatacijos metu. Šių parametrų ţinojimas nulemia tolimesnę patobulintos geoterminės sistemos (Enhanced geothermal system, EGS) kūrimą. Aukšto slėgio geoterminis skystis spaudžiamas į porėtą uoliena, sąveikauja su ją sudarančiais mineralais ir deformuoja ją hidrosuplėšymo metu, taip praplėsdamas ir atverdamas naujus plyšius. Ši technologija yra vadinama stimuliuota sausų uolienų geoterminė sistema (Hot dry rock, HDR). Šių sistemų tikslas yra poţeminio šilumokaičio sukūrimas, pumpuojant aukšto slėgio vandens srautą į kristalinį pamatą. Taip formuojamas stimuliuotų plyšių koridorius, kuriuo cirkuliuoja gręžiniais pumpuojamas vanduo. / The geothermal energetic was found interesting for an anomalous heat flow at the west Lithuanian that is the most intense in a whole East European Platform. A higher temperature than 150 ºC is available in crystal basement at Lithuania at less than 5 km depth. To measure basic parameters of geothermal anomaly, geophysical and geochemical methods are applied. The other measurements are taken at the moment of hydrocirculation. Knowledge of these parameters will be used for the development and improvement of the enhanced geothermal system (EGS). High pressured water geothermal fluid is pumped into the rock in purpose to open old and create new cracks and fractures by exceeding rock compressive stress. For this reason there was created hot dry rock (HDR) system. The main goal of this system is to create a geothermal reservoir by pumping high pressure water flow into the rock. This way water circulates in enhanced geothermal system through the tunnel of fractures.

The purpose of this research was to determine the potential capacity for improved participation through community-based approaches to small hydroelectric development in the Indian Himalayas. The objectives of the research were: (1) to establish the current roles of the civic, public and private sectors in small hydro development; (2) to examine the potential for learning through participation during the development of small hydro projects; (3) to determine the potential for using community-based environmental assessment in future projects; (4) to investigate the benefits of community-driven small hydro development, and (5) to determine the implications of the findings for environmental policy and decision-making. Data were gathered using Participatory Rural Appraisal methods including semi-structured interviews, transect walks, and landscape analysis. There were five case study projects (Niti, Bampa, Jumma, Malari and Bamini/Badrinath), each in the Indo-Tibetan border region of the Indian Himalayas. The plants are all run of river, and range in capacity from 25 kW to 1.2 MW. Four of the villages had no electricity prior to the development of the small-hydro plants, while one had a prior connection to the state electrical grid (Bamini/Badrinath). The villages are inhabited by Bhotia tribespeople, and are occupied only during the summer growing season. The residents travel to lower altitude villages for the winter months. The most successful project examined, in the village of Malari, was one where community development and energy needs were considered simultaneously, and where the local community was highly involved in planning, construction and operation. The less successful projects were those where community involvement and development, sound planning, and detailed geographic information about the site were lacking in their development and operation; such as was observed in the village of Jumma, where the plant never began operations because it was damaged by an avalanche prior to its inauguration. PLEASE NOTE: As of January 2007 the State of Uttaranchal was renamed Uttarakhand. The change is not reflected in this thesis.

Les travaux de modélisations présentes dans cette thèse concernent l'étude du comportement hydro-poro-mécanique des géomatériaux par l'approche numérique de changement d'échelle. Il s'agit d'exploiter un modèle géomatériaux conceptuel, du code de calcul par la méthode élément finis étendu (XFEM) ou IIM, conjointement avec des techniques d'homogénéisation, pour l'obtention des lois de comportement macroscopique tirées des relations de passage Micro-Macro. Dans ce modèle conceptuel, le volume élémentaire représentatif des milieux hétérogène est composé d'une matrice argileuse contenant des inclusions de minéraux de quartz et de calcite ou des pores. D'abord, cette procedure avec XFEM a été effectuée pour la détermination des propriétés effectives isotropes. Ensuite, Une étude sur l'influence de la distribution, la morphologie, et l'orientation des inclusions sur le comportement équivalent dans le domaine de l'élasticité linéaire a été réalisée par traverser nombreuse études numériques. Dans un troisièmes temps, nous avons modélisée le comportement mécanique non linaire des géomatériaux en utilisant XFEM et la méthode Newton-Raphson modifiée. Enfin, la modélisation du comportement hydraulique est réalisée par la méthode IIM, elle a été validée par la comparaison avec l'approche analytique.

Les résultats de cette recherche concernent trois volets :<br />Le volet théorique (partie I) présente une modélisation générale du comportement thermo-hydro-mécanique de sols non saturés. Le modèle prend en compte la déformation du squelette, la filtration des phases liquide et gazeuse, la diffusion de vapeur, la conduction de chaleur et le changement de phase liquide-vapeur. Cette modélisation est utilisée pour décrire le transport d'eau dans un sol non saturé en favorisant les phénomènes de filtration de liquide, de diffusion de vapeur d'eau et de changement de phase d'eau liquide-vapeur. <br />Le volet instrumental (partie II) porte sur la réalisation d'un banc de sorption et d'un dispositif de type plaque de pression en température. Ces matériels permettent de réaliser des essais de désaturation et de déterminer la courbe caractéristique sol-eau. Un autre aspect concerne la rénovation d'un appareil triaxial thermique en le dotant d'une instrumentation plus adaptée à l'étude du comportement thermo-hydro-mécanique de sols non saturés.<br />Le volet expérimental est double. Le premier aspect (partie III), relatif à l'étude de la désaturation et à la détermination de la courbe caractéristique d'une argile plastique et d'un sable limoneux argileux à 20°C et 60°C, porte sur la détermination d'un coefficient de transport en phase liquide. Le second aspect (partie IV) s'intéresse à la représentation de surfaces de charge dans le cas du sable limoneux argileux non saturé à différentes températures. Cette surface de charge présente un caractère thermo-extensif dont on propose une modélisation et une interprétation physique.

Global energy consumption will increase in the next decades and it is expected to largely rely on fossil fuels. The use of fossil fuels is intimately related to CO₂ emissions and the potential for global warming. Geological CO₂ storage aims to mitigate the global warming problem by sequestering CO₂ underground. Coupled hydro-chemo-mechanical phenomena determine the successful operation and long term stability of CO₂ geological storage. This research explores various coupled phenomena, identifies different zones in the storage reservoir, and investigates their implications in CO₂ geological storage. Spatial patterns in mineral dissolution and precipitation are examined based on a comprehensive mass balance formulation. CO₂-dissolved fluid flow is modeled using a novel technique that couples laminar flow, advective and diffusive mass transport of species, mineral dissolution, and consequent pore changes to study the reactive fluid transport at the scale of a single rock fracture. The methodology is extended to the scale of a porous medium using pore network simulations to study both CO₂ reservoirs and caprocks. The two-phase flow problem between immiscible CO₂ and the formation fluid (water or brine) is investigated experimentally. Plug tests on shale and cement specimens are used to investigate CO₂ breakthrough pressure. Sealing strategies are explored to plug existing cracks and increase the CO₂ breakthrough pressure. Finally, CO₂-water-surfactant mixtures are evaluated to reduce the CO₂-water interfacial tension in view of enhanced sweep efficiency. Results can be used to identify optimal CO₂ injection and remediation strategies to maximize the efficiency of CO₂ injection and to attain long-term storage.

The purpose of this research was to determine the potential capacity for improved participation through community-based approaches to small hydroelectric development in the Indian Himalayas. The objectives of the research were: (1) to establish the current roles of the civic, public and private sectors in small hydro development; (2) to examine the potential for learning through participation during the development of small hydro projects; (3) to determine the potential for using community-based environmental assessment in future projects; (4) to investigate the benefits of community-driven small hydro development, and (5) to determine the implications of the findings for environmental policy and decision-making. Data were gathered using Participatory Rural Appraisal methods including semi-structured interviews, transect walks, and landscape analysis. There were five case study projects (Niti, Bampa, Jumma, Malari and Bamini/Badrinath), each in the Indo-Tibetan border region of the Indian Himalayas. The plants are all run of river, and range in capacity from 25 kW to 1.2 MW. Four of the villages had no electricity prior to the development of the small-hydro plants, while one had a prior connection to the state electrical grid (Bamini/Badrinath). The villages are inhabited by Bhotia tribespeople, and are occupied only during the summer growing season. The residents travel to lower altitude villages for the winter months. The most successful project examined, in the village of Malari, was one where community development and energy needs were considered simultaneously, and where the local community was highly involved in planning, construction and operation. The less successful projects were those where community involvement and development, sound planning, and detailed geographic information about the site were lacking in their development and operation; such as was observed in the village of Jumma, where the plant never began operations because it was damaged by an avalanche prior to its inauguration. PLEASE NOTE: As of January 2007 the State of Uttaranchal was renamed Uttarakhand. The change is not reflected in this thesis.

The lower Churchill River has been an important travel route for people living in its vicinity for a long period of time. Churchillians’ have used it for subsistence harvesting, as their potable water source and as a place of recreation and relaxation. Previous research has documented the importance of the Churchill River to the residents and has explored how the Churchill River Diversion affected the community of Churchill (Boothroyd, 1992; 2000; Four Directions Consulting Group, 1994; 1995). The purpose of this project was to identify how Churchill residents used the lower Churchill River (from 1970 to 2006), recognizing three distinct periods of time. Twenty interviews were conducted with former or current long-term residents of Churchill, as well as two interviews with experts on issues concerning the lower Churchill River. Many interviewees stated that additional negotiations and measures are required before they deem the mitigation compensation package from Manitoba Hydro to be adequate considering the impact of the diversion on the residents of Churchill.

Glaciation is considered one of the main natural processes that can have a significant impact on the long term performance of DGRs. The northern part of the American continent has been subjected to a series of strong glaciation and deglaciation events over the past million years. Glacial cycles cause loading and unloading, temperature changes and hydraulic head changes at the ground surface. These changes can be classified as transient boundary conditions. It is widely accepted that the periodic pattern of past glacial cycles during the Late Quaternary period are resultant of the Earth’s orbital geometry changes that is expected to continue in the future. Therefore, from the safety perspective of DGRs, such probable events need to be taken into account. The objective of this thesis is to develop a numerical model to investigate the thermo-hydro-mechanical-chemical (THMC) coupled processes that have resulted from long term past and future climate changes and glaciation cycles on a proposed DGR in sedimentary rocks in southern Ontario. The first application is done on a large geological cross section that includes the entire Michigan basin by using a hydro-mechanical (HM) coupled process. The results are compared with field data of anomalous pore water pressures from deep boreholes in sedimentary rocks of southern Ontario. In this work. The modeling results seem to support the hypothesis that at least the underpressures in the Ordovician formation could be partially attributed to past glaciation. The second application is made on site conditions by using the THMC model. The results for the pore water pressure, tracer profiles, permafrost depth and effective stress profile are compared with the available field data, the results show that the solute transport in the natural limestone and shale barrier formations is controlled by diffusion, which provide evidence that the main mechanism of transport at depth is diffusion-dominant. The third application is made on site conditions to determine the effect of underground changes in DGRs due to DGR construction. The results show that future glaciation loads will induce larger increases in effective stresses on the shaft. Furthermore, it is found that hypothetical nuclide transport in a failed shaft can be controlled by diffusion and advection. The simulation results show that the solute transported in a failed shaft can reach the shallow bedrock groundwater zone. These results might imply that a failed shaft will substantially lose its effectiveness as a barrier. The fourth application is proposed to investigate the geochemical evolution of sedimentary host rock in a near field scale. In this part, a new thermo-hydro-mechanical-geochemical simulator (COMSOL-PHREEQC) is developed. It is anticipated that there will be a geochemical reaction within the host rock that results from interaction with the water enriched with the CO2 generated by nuclear waste.

In Canada, First Nations asserting authority over their lands are developing diverse strategies to overcome the state’s dogmatic insistence on jurisdictional sovereignty. This movement corresponds to the wider context of the challenges faced by indigenous people to use their own ways of knowing to resist or reformulate legal doctrines and political tenets based on colonial power. Interior Salish St’át’imc people identify themselves through a strong and ongoing social relationship with Satáqwa7, the Fraser River, and the “Valley of Plenty”— now known as the flooded Bridge River Valley – maintained through St’át’imc knowledge and cultural practice and demonstrated by talk of “the St’át’imc right to fish” and Tsuwalhkálh Ti Tmícwa (The Land is Ours). St’át’imc fishers are prepared to contest and resist any regulatory system that is understood to impact this right to fish while they advocate their own ways of sustainable fishing and water management. Based on ethnographic research in collaboration with St’át’imc people, this thesis explores some of these often successful contestations especially in the context of increasing territorial governance and by example of the rapidly transforming relationship between St’át’imc, BC Hydro and the Province of BC. Interior Salish St’át’imc people are currently navigating through a significant phase of increasing jurisdiction and authority and recognition of (unsettled) territorial property relationships. This very dynamic process is marked by strategic collaborations, compensation for ‘infringements’ on St’át’imc Title and Rights, and conservation efforts to protect their home. An important example is the changing relationship between St’át’imc people and BC Hydro – a relationship between two groups with radically different cultures and agendas: St’át’imc people in a struggle for self-determination, social justice and cultural survival and BC Hydro, a corporate culture, with the agenda to provide hydro-electric power to BC, maintain operation ‘certainty’ and to generate revenue. Exploring the different ways of relating to and acting on the land will allow for more holistic and shared cultural practices of co-governing land, working collectively, remembering history, co-existing in the present and sharing a common future according to the ethical ideals of reconciliation: accountability for wrongdoing, justice, sharing, respect, transcending of hegemonic silences and increased public knowledge. / Graduate

Thesis (Ph.D.)--University of Tasmania, 2004. / Includes bibliographical references.