Il existe en France des centaines de friches industrielles polluées par du goudron de houille, un mélange récalcitrant de composés tels que les hydrocarbures aromatiques polycycliques. Lorsque la zone non saturée des sols est fortement contaminée, elle est usuellement excavée et remblayée. Cette thèse porte sur un traitement alternatif permettant une valorisation potentielle des sols sur site : l’oxydation chimique in situ, qui a déjà montré des résultats encourageants au laboratoire mais n’a que très peu été testée en grandeurs réelles. Les recherches ont donc été menées autour de trois échelles – bibliographie, laboratoire et pilote – afin de déterminer s’il existait un traitement oxydant répondant à des critères techniques, économiques et environnementaux acceptables pour être appliquée à l’échelle de la friche. La phase laboratoire a montré que l’ajout d’un soutien thermique augmentait significativement l’efficacité du traitement, i) par augmentation de la disponibilité de la pollution par préchauffage de la terre dans le cas du permanganate, ou ii) par activation thermique de l’oxydant dans le cas du persulfate. A l’échelle du pilote, une mise en contact homogène entre l’oxydant et la pollution n’a été possible que par noyage partiel de la terre avec les solutions oxydantes concentrées. L’activation du persulfate s’est révélée délicate à mettre en œuvre, le chauffage de solutions concentrées ayant mené à une décomposition parasite de l’oxydant. Au contraire, l’utilisation de solutions concentrées de permanganate a conduit à une dégradation des polluants encore plus élevée qu’au laboratoire grâce à la forte exothermicité de la réaction / In France, hundreds of brownfields are currently polluted with coal tar, a complex and recalcitrant mixture of organic compounds such as polycyclic aromatic hydrocarbons. When the unsaturated zone of soils is highly contaminated, it is commonly excavated and backfilled. This work deals with an alternative treatment, in situ chemical oxidation, that allows a potential reuse of soils directly on site. This technique has already provided encouraging results at the lab scale but has rarely been tested in the field. Research was made around three scales – bibliography, laboratory and pilot – in order to respond to the main problem: is there an oxidative treatment able to meet technical, economic and environmental criteria quite acceptable to be applied at brownfield level? The laboratory research phase showed that the addition of a moderate thermal support significantly increased treatment effectiveness, by i) an increase in pollutant availability by soil preheating in the case of permanganate, or ii) a thermal activation of the oxidant in the case of persulfate. At the pilot scale, a homogeneous contact between the oxidant and the pollutants was possible only by a partial flooding of the soil with the concentrated oxidizing solutions. The persulfate activation turned out to be difficult to implement because heating concentrated solutions led to a parasite decomposition of the oxidant. On the contrary, the use of concentrated solutions of permanganate led to an even higher degradation than in the laboratory, as a result of the strong exothermicity of the reaction

In brownfield regeneration models, extraction sites are often left out of the question because of degradation, severe contamination, or economic viability and are usually abandoned, after the minimal remediations. These exhaustions not only impact the environment and economy in spatial relations but also influence the growth of the communities cultured by them. With millions of abandoned sites around the globe, there is a demand for building a vision that develops - the ideas of emergence and diversification over time and space, as a base framework for similar towns and communities before they disappear. Underpinning the urgent need and evolving theme of ecologies, 'Reclaiming Kiruna' is an investigation of a vision for a post-exhaustion site of Kiruna mine, which is the world's largest underground mine, by developing landscape ecologies in the present framework that builds and adapts with time and space before the mine gets exhausted. The project reveals the concept of landscape as an amalgamation of production and recreation ecologies, synergizing with the existing potentials of nature, resources, and society. The work focuses on translating the knowns and unknowns of three time periods, synced with proposed plans of the New Kiruna settlement area, through programs of care and thinking that involve, engage, and encourage people (of Kiruna) in redefining the image of Kiruna beyond just a mine. The project unfolds new prospects offered by planned urban transformations, mining systems, and changing climate, which are integrated into building new economies and relations. The project is limited by the uncertainty of the future but attempts to initiate a dialogue in finding new positions as urban designers to contest with the present frameworks in building alternatives of change and novelty, for a sustainable future.

Based on qualitative, case study and the analysis of Europacity project in Berlin, this study aims at assessing the important criteria in order to evaluate the economic dimensions and development potential of a brownfield and a brownfield project. In the literature, more contextual information is given by making an updated state of the arts of brownfield regeneration financing and framework in the European Union with a particular focus on Germany. Furthermore, tools to evaluate the development potential of particular brownfield regeneration projects in particular brownfields and costs-benefits analysis in this field are reviewed. Using a compilation of official and informal data acquired through the interview of one main institutional actor in the development of the Europacity project, the author tried to assess the factors influencing the successful completion of the project in this area, the impacts of the project on eight selected items (stakeholders involvement and following values: economic, social, environmental, historical, psychological, spatial and technological) and the costs-benefits analysis for three of the main stakeholders of the project. The main finding is that all items studied were relevant to some extent in the economic evaluation of a brownfield regeneration project.