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Underground thermal energy storage is an efficient technique to boost the share of renewable energies. However, despite being well-established, their environmental impacts such as the interaction with hydrocarbon contaminants is not intensively investigated. This study uses OpenGeoSys software to simulate the heat and mass transport of a borehole thermal energy storage (BTES) system in a shallow unconfined aquifer. A high-temperature (70 C) heat storage scenario was considered which imposes long-term thermal impact on the subsurface. Moreover, the effect of temperature-dependent flow and mass transport in a two-phase system is examined for the contaminant trichloroethylene (TCE). In particular, as subsurface temperatures are raised due to BTES operation, volatilization will increase and redistribute the TCE in liquid and gas phases. These changes are inspected for different scenarios in a contaminant transport context. The results demonstrated the promising potential of BTES in facilitating the natural attenuation of hydrocarbon contaminants, particularly when buoyant flow is induced to accelerate TCE volatilization. For instance, over 70% of TCE mass was removed from a discontinuous contaminant plume after 5 years operation of a small BTES installation. The findings of this study are insightful for an increased application of subsurface heat storage facilities, especially in contaminated urban areas.

<p>In urban areas where the shallow subsurface is used for thermal energy storage (TES), interactions between the introduced heat and groundwater pollution caused by toxic organic contaminants can be expected. Temperature elevations may affect the transfer of these volatile organic compounds (VOCs) from the groundwater to the unsaturated zone, creating a redistribution or release of the contaminants in/from the subsurface environment. Such effects are particularly important considering the intersection of the unsaturated zone with the land surface and the remediation capacity of polluted aquifers. In this work, a non-isothermal multi-component two-phase flow model was developed to investigate the thermally induced volatilization and migration of the VOCs in contaminated aquifers. The numerical model, which is implemented in the open source framework <em>OpenGeoSys</em>-6, is able to simulate temperature-dependent mass and heat transfer processes in partially-saturated soils while allowing for phase change. Verification of the model against various benchmark problems and experimental data showed good accuracy. Simulation results revealed that a temperature-driven migration of dissolved trichloroethylene (TCE) from the groundwater to the drier regions of the unsaturated zone can be observed in general. A temperature increase of 20 K around the borehole led to a maximum decline of the total TCE concentration by 63% assuming zero TCE concentration at the soil surface. In addition, the TCE concentration distribution varied considerably with the depth-dependent water saturation. Further investigations were carried out to study the effects of different parameters, e.g. groundwater velocity, contaminant type and boundary conditions. Based on our analysis, the planning of subsurface TES systems can be optimized to account for the possible interactions with pre-existing groundwater contamination.</p><p><strong>References:</strong></p><p>Kolditz, O., Bauer, S., Bilke, L., Böttcher, N., Delfs, J. O., Fischer, T., ... & Zehner, B. (2012). OpenGeoSys: an open-source initiative for numerical simulation of thermo-hydro-mechanical/chemical (THM/C) processes in porous media. <em>Environmental Earth Sciences</em>, <em>67</em>(2), 589-599.</p>

This study is a review of a selection of the literature on eating disorders. This study, focusing on anorexia nervosa, includes its prevalence, etiology, impacts, treatments, and recommendations for future development. This study also explores the performance of family therapy for anorexia nervosa in adolescents. The results and discussion section presents the possible causes of eating disorders, such as anorexia nervosa, from biological and social perspectives. The current study also articulates the impact of anorexia nervosas on individuals, social relationships, and social, emotional functioning. Recommendations in the conclusion section provide directions for future research. Overall, the audience will be able to acquire some general knowledge about eating disorders and learn about the efficacy of family therapy with eating disorders.