Cada vez mais freqüente, a utilização de técnicas tradicionais da engenharia geotécnica depara-se com obstáculos de caráter econômico e ambiental. A técnica do solo-cimento tornase atrativa quando o melhoramento das propriedades do solo do local constitui-se em uma alternativa de projeto. A técnica de tratamento de solos com cimento encontra aplicação, por exemplo, na construção de bases para pavimentos, na proteção de taludes em barragens de terra, como camada de suporte para fundações superficiais, como remediação de solos contaminados e como barreiras de contenção de contaminantes. Desta forma, esta tese tem por objetivo analisar a influência da quantidade de cimento, da porosidade e da umidade de moldagem sobre o comportamento físico e químico de um solo argiloso artificialmente cimentado e contaminado. O programa experimental consiste em caracterizar os materiais utilizados, analisar fisicamente as misturas solo-cimento e solo-cimento-contaminante, através de ensaios de resistência à compressão simples, medidas de sucção e condutividade hidráulica. Quimicamente serão realizados ensaios de lixiviação em coluna e análises químicas e físico-químicas do lixiviado. Os resultados, quanto à caracterização, apresentam um material argiloso, oriundo de rochas riodacitos (riolito/dacito); quanto à resistência à compressão simples houve um aumento de resistência com o aumento da quantidade de cimento e com o aumento do peso especifico de compactação; quanto ao solo contaminado e cimentado ocorreu o mesmo comportamento, porém, com queda de resistência. A condutividade hidráulica obteve um decréscimo quando aumentado o peso especifico de moldagem, tanto para solo-cimento como para solo-cimento-contaminante. Para as análises químicas, a partir do ensaio de lixiviação, contatou-se redução de parâmetros de contaminação com a adição de cimento, principalmente com o aumento significativo do pH, devido ao aumento da quantidade de cimento. Concluiu-se que a quantidade de cimento e a diminuição da porosidade ocorrida pela maior densificação influenciam em ganho de resistência, à uma baixa permeabilidade e à uma baixa concentração de contaminante no lixiviado. / More and more the use of traditional techniques of the geotechnical engineering comes across obstacles of economic and environmental character. The technique of the soil-cement becomes attractive when the improvement of the properties of the local soil constituted in a project alternative. The technique of treatment of soils with cement finds application, for instance, in the construction of bases for pavements, in the protection of talus in land dams, as support layer for superficial foundations, as remediation of polluted soils and as barriers of contention of pollutants. This way, this theory has as objective to analyze the influence of the amount of cement, of the porosity and of the molding humidity over the physical and chemical behavior of a loamy soil artificially cemented and polluted. The experimental program consists of characterizing the used materials, to analyze the mixtures soil-cement and soil-cement-pollutant physically, through resistance samples to the simple compression, suction measures and hydraulic conductivity. The lixiviation samples will be chemically accomplished in column and chemical and physiochemical analyses of the lixiviated. The results, according to the characterization, present a loamy material, originating from rocks rhyodacite (rhyolite/dacite); according to the resistance to the simple compression there was a resistance increase with the rise of the amount of cement and with the increase of the weight specific of compaction; as for the polluted soil and cemented happened the same behavior, however, with resistance fall. The hydraulic conductivity suffered a decrease when increased the specific weight of molding, for soil-cement and for soil-cement-pollutant. (Continue For the chemical analyses, starting from the lixiviation samples, it was reached a reduction of parameters of contamination with the cement addition, mainly with the significant increase of the pH, due to the increase of the amount of cement. It was concluded that the amount of cement and the decrease of the porosity happened by the largest densification influence in resistance adding, as well as they provide a low permeability and a low pollutant concentration in the lixiviated. / Cada vez más la utilización de técnicas tradicionales de la ingeniería geotécnica se depara con obstáculos de carácter económico y ambiental. La técnica del suelo-cemento se vuelve atractiva cuando el mejoramiento de las propiedades del suelo local se constituye en una alternativa de proyecto. La técnica de tratamiento de suelos con cemento encuentra aplicación, por ejemplo, en la construcción de bases para pavimentos, en la protección de taludes, en presas de tierra, como camada de soporte para fundaciones superficiales, como remediación de suelos contaminados y como barreras de contención de contaminantes. Esta tesis tiene por objetivo analizar la influencia de la cantidad de cemento, de la porosidad y de la humedad del molde, sobre el comportamiento físico y químico de un suelo arcilloso artificialmente cementado y contaminado. El programa experimental consiste en caracterizar los materiales utilizados, analizar físicamente las mezclas suelo-cemento y suelo-cementocontaminante a través de ensayos de resistencia a compresión simple, medidas de succión y conductividad hidráulica. Químicamente serán realizados ensayos de lixiviación en columna y análisis químicos y físico-químicos del lixiviado. Los resultados, con respecto a la caracterización, presentan un material arcilloso, oriundo de rocas riodacitos (riolito/dacito). En cuanto a la resistencia el aumento de la misma es directamente proporcional al aumento de la cantidad de cemento y del peso especifico de compactación, referente al suelo contaminado y cementado ocurrió el mismo comportamiento, pero con disminución de resistencia. La conductividad hidráulica obtuvo una reducción cuando se produjo el aumento del peso específico, tanto para suelo-cemento como para suelo-cemento-contaminante. Para los análisis químicos, a partir del ensayo de lixiviación, se constato reducción de parámetros de contaminación con la adición de cemento, principalmente con el aumento significativo del pH. Se concluyó que la cantidad de cemento y la disminución de la porosidad ocurrida por l mayor compampactacion influencio en el aumento de resistencia, asi como porporciono baja permeabilidad y baja concentración de contaminante en el lixiviado.

Cada vez mais freqüente, a utilização de técnicas tradicionais da engenharia geotécnica depara-se com obstáculos de caráter econômico e ambiental. A técnica do solo-cimento tornase atrativa quando o melhoramento das propriedades do solo do local constitui-se em uma alternativa de projeto. A técnica de tratamento de solos com cimento encontra aplicação, por exemplo, na construção de bases para pavimentos, na proteção de taludes em barragens de terra, como camada de suporte para fundações superficiais, como remediação de solos contaminados e como barreiras de contenção de contaminantes. Desta forma, esta tese tem por objetivo analisar a influência da quantidade de cimento, da porosidade e da umidade de moldagem sobre o comportamento físico e químico de um solo argiloso artificialmente cimentado e contaminado. O programa experimental consiste em caracterizar os materiais utilizados, analisar fisicamente as misturas solo-cimento e solo-cimento-contaminante, através de ensaios de resistência à compressão simples, medidas de sucção e condutividade hidráulica. Quimicamente serão realizados ensaios de lixiviação em coluna e análises químicas e físico-químicas do lixiviado. Os resultados, quanto à caracterização, apresentam um material argiloso, oriundo de rochas riodacitos (riolito/dacito); quanto à resistência à compressão simples houve um aumento de resistência com o aumento da quantidade de cimento e com o aumento do peso especifico de compactação; quanto ao solo contaminado e cimentado ocorreu o mesmo comportamento, porém, com queda de resistência. A condutividade hidráulica obteve um decréscimo quando aumentado o peso especifico de moldagem, tanto para solo-cimento como para solo-cimento-contaminante. Para as análises químicas, a partir do ensaio de lixiviação, contatou-se redução de parâmetros de contaminação com a adição de cimento, principalmente com o aumento significativo do pH, devido ao aumento da quantidade de cimento. Concluiu-se que a quantidade de cimento e a diminuição da porosidade ocorrida pela maior densificação influenciam em ganho de resistência, à uma baixa permeabilidade e à uma baixa concentração de contaminante no lixiviado. / More and more the use of traditional techniques of the geotechnical engineering comes across obstacles of economic and environmental character. The technique of the soil-cement becomes attractive when the improvement of the properties of the local soil constituted in a project alternative. The technique of treatment of soils with cement finds application, for instance, in the construction of bases for pavements, in the protection of talus in land dams, as support layer for superficial foundations, as remediation of polluted soils and as barriers of contention of pollutants. This way, this theory has as objective to analyze the influence of the amount of cement, of the porosity and of the molding humidity over the physical and chemical behavior of a loamy soil artificially cemented and polluted. The experimental program consists of characterizing the used materials, to analyze the mixtures soil-cement and soil-cement-pollutant physically, through resistance samples to the simple compression, suction measures and hydraulic conductivity. The lixiviation samples will be chemically accomplished in column and chemical and physiochemical analyses of the lixiviated. The results, according to the characterization, present a loamy material, originating from rocks rhyodacite (rhyolite/dacite); according to the resistance to the simple compression there was a resistance increase with the rise of the amount of cement and with the increase of the weight specific of compaction; as for the polluted soil and cemented happened the same behavior, however, with resistance fall. The hydraulic conductivity suffered a decrease when increased the specific weight of molding, for soil-cement and for soil-cement-pollutant. (Continue For the chemical analyses, starting from the lixiviation samples, it was reached a reduction of parameters of contamination with the cement addition, mainly with the significant increase of the pH, due to the increase of the amount of cement. It was concluded that the amount of cement and the decrease of the porosity happened by the largest densification influence in resistance adding, as well as they provide a low permeability and a low pollutant concentration in the lixiviated. / Cada vez más la utilización de técnicas tradicionales de la ingeniería geotécnica se depara con obstáculos de carácter económico y ambiental. La técnica del suelo-cemento se vuelve atractiva cuando el mejoramiento de las propiedades del suelo local se constituye en una alternativa de proyecto. La técnica de tratamiento de suelos con cemento encuentra aplicación, por ejemplo, en la construcción de bases para pavimentos, en la protección de taludes, en presas de tierra, como camada de soporte para fundaciones superficiales, como remediación de suelos contaminados y como barreras de contención de contaminantes. Esta tesis tiene por objetivo analizar la influencia de la cantidad de cemento, de la porosidad y de la humedad del molde, sobre el comportamiento físico y químico de un suelo arcilloso artificialmente cementado y contaminado. El programa experimental consiste en caracterizar los materiales utilizados, analizar físicamente las mezclas suelo-cemento y suelo-cementocontaminante a través de ensayos de resistencia a compresión simple, medidas de succión y conductividad hidráulica. Químicamente serán realizados ensayos de lixiviación en columna y análisis químicos y físico-químicos del lixiviado. Los resultados, con respecto a la caracterización, presentan un material arcilloso, oriundo de rocas riodacitos (riolito/dacito). En cuanto a la resistencia el aumento de la misma es directamente proporcional al aumento de la cantidad de cemento y del peso especifico de compactación, referente al suelo contaminado y cementado ocurrió el mismo comportamiento, pero con disminución de resistencia. La conductividad hidráulica obtuvo una reducción cuando se produjo el aumento del peso específico, tanto para suelo-cemento como para suelo-cemento-contaminante. Para los análisis químicos, a partir del ensayo de lixiviación, se constato reducción de parámetros de contaminación con la adición de cemento, principalmente con el aumento significativo del pH. Se concluyó que la cantidad de cemento y la disminución de la porosidad ocurrida por l mayor compampactacion influencio en el aumento de resistencia, asi como porporciono baja permeabilidad y baja concentración de contaminante en el lixiviado.

Cada vez mais freqüente, a utilização de técnicas tradicionais da engenharia geotécnica depara-se com obstáculos de caráter econômico e ambiental. A técnica do solo-cimento tornase atrativa quando o melhoramento das propriedades do solo do local constitui-se em uma alternativa de projeto. A técnica de tratamento de solos com cimento encontra aplicação, por exemplo, na construção de bases para pavimentos, na proteção de taludes em barragens de terra, como camada de suporte para fundações superficiais, como remediação de solos contaminados e como barreiras de contenção de contaminantes. Desta forma, esta tese tem por objetivo analisar a influência da quantidade de cimento, da porosidade e da umidade de moldagem sobre o comportamento físico e químico de um solo argiloso artificialmente cimentado e contaminado. O programa experimental consiste em caracterizar os materiais utilizados, analisar fisicamente as misturas solo-cimento e solo-cimento-contaminante, através de ensaios de resistência à compressão simples, medidas de sucção e condutividade hidráulica. Quimicamente serão realizados ensaios de lixiviação em coluna e análises químicas e físico-químicas do lixiviado. Os resultados, quanto à caracterização, apresentam um material argiloso, oriundo de rochas riodacitos (riolito/dacito); quanto à resistência à compressão simples houve um aumento de resistência com o aumento da quantidade de cimento e com o aumento do peso especifico de compactação; quanto ao solo contaminado e cimentado ocorreu o mesmo comportamento, porém, com queda de resistência. A condutividade hidráulica obteve um decréscimo quando aumentado o peso especifico de moldagem, tanto para solo-cimento como para solo-cimento-contaminante. Para as análises químicas, a partir do ensaio de lixiviação, contatou-se redução de parâmetros de contaminação com a adição de cimento, principalmente com o aumento significativo do pH, devido ao aumento da quantidade de cimento. Concluiu-se que a quantidade de cimento e a diminuição da porosidade ocorrida pela maior densificação influenciam em ganho de resistência, à uma baixa permeabilidade e à uma baixa concentração de contaminante no lixiviado. / More and more the use of traditional techniques of the geotechnical engineering comes across obstacles of economic and environmental character. The technique of the soil-cement becomes attractive when the improvement of the properties of the local soil constituted in a project alternative. The technique of treatment of soils with cement finds application, for instance, in the construction of bases for pavements, in the protection of talus in land dams, as support layer for superficial foundations, as remediation of polluted soils and as barriers of contention of pollutants. This way, this theory has as objective to analyze the influence of the amount of cement, of the porosity and of the molding humidity over the physical and chemical behavior of a loamy soil artificially cemented and polluted. The experimental program consists of characterizing the used materials, to analyze the mixtures soil-cement and soil-cement-pollutant physically, through resistance samples to the simple compression, suction measures and hydraulic conductivity. The lixiviation samples will be chemically accomplished in column and chemical and physiochemical analyses of the lixiviated. The results, according to the characterization, present a loamy material, originating from rocks rhyodacite (rhyolite/dacite); according to the resistance to the simple compression there was a resistance increase with the rise of the amount of cement and with the increase of the weight specific of compaction; as for the polluted soil and cemented happened the same behavior, however, with resistance fall. The hydraulic conductivity suffered a decrease when increased the specific weight of molding, for soil-cement and for soil-cement-pollutant. (Continue For the chemical analyses, starting from the lixiviation samples, it was reached a reduction of parameters of contamination with the cement addition, mainly with the significant increase of the pH, due to the increase of the amount of cement. It was concluded that the amount of cement and the decrease of the porosity happened by the largest densification influence in resistance adding, as well as they provide a low permeability and a low pollutant concentration in the lixiviated. / Cada vez más la utilización de técnicas tradicionales de la ingeniería geotécnica se depara con obstáculos de carácter económico y ambiental. La técnica del suelo-cemento se vuelve atractiva cuando el mejoramiento de las propiedades del suelo local se constituye en una alternativa de proyecto. La técnica de tratamiento de suelos con cemento encuentra aplicación, por ejemplo, en la construcción de bases para pavimentos, en la protección de taludes, en presas de tierra, como camada de soporte para fundaciones superficiales, como remediación de suelos contaminados y como barreras de contención de contaminantes. Esta tesis tiene por objetivo analizar la influencia de la cantidad de cemento, de la porosidad y de la humedad del molde, sobre el comportamiento físico y químico de un suelo arcilloso artificialmente cementado y contaminado. El programa experimental consiste en caracterizar los materiales utilizados, analizar físicamente las mezclas suelo-cemento y suelo-cementocontaminante a través de ensayos de resistencia a compresión simple, medidas de succión y conductividad hidráulica. Químicamente serán realizados ensayos de lixiviación en columna y análisis químicos y físico-químicos del lixiviado. Los resultados, con respecto a la caracterización, presentan un material arcilloso, oriundo de rocas riodacitos (riolito/dacito). En cuanto a la resistencia el aumento de la misma es directamente proporcional al aumento de la cantidad de cemento y del peso especifico de compactación, referente al suelo contaminado y cementado ocurrió el mismo comportamiento, pero con disminución de resistencia. La conductividad hidráulica obtuvo una reducción cuando se produjo el aumento del peso específico, tanto para suelo-cemento como para suelo-cemento-contaminante. Para los análisis químicos, a partir del ensayo de lixiviación, se constato reducción de parámetros de contaminación con la adición de cemento, principalmente con el aumento significativo del pH. Se concluyó que la cantidad de cemento y la disminución de la porosidad ocurrida por l mayor compampactacion influencio en el aumento de resistencia, asi como porporciono baja permeabilidad y baja concentración de contaminante en el lixiviado.

No description available.

D’après le répertoire des terrains contaminés du MELCC, le Grand Montréal compte plus de 11 000 sites pollués. Une approche pour l’assainissement de ces terrains est la phytoremédiation, une stratégie qui utilise la faculté de certaines plantes pour réduire les concentrations des contaminants in situ. Une contrainte associée à la végétalisation des sites contaminés est le risque de bioaccumulation dans la chaîne alimentaire. Une solution serait l’utilisation de polycultures tirant profit de la combinaison d’espèces végétales aux caractéristiques différentes. L’objectif principal de cette étude était de comparer l’accumulation d’éléments traces d’une plante alimentaire (Solanum lycopersicum—tomate cerise) et de plantes « phytoremédiatrices » (Salix discolor—Saule discolor, Achillea millefolium—achillée millefeuille, Trifolium repens—trèfle blanc) lorsque cultivées en compagnonnage sur des sols contaminés. Quinze traitements ont été examinés : cinq assemblages de plantes et trois sols (technosol à 110 mg Cu kg-1, technosol dopé jusqu’à 2500 mg Cu kg-1 et un sol de jardin non contaminé). Les résultats ont montré (1) que les polycultures incluant T. repens étaient les plus performantes à produire de la biomasse et à phytoextraire le cuivre, (2) que les stress (c.-à-d. compétition et ressource en eau) ont clairement amoindri les performances de S. discolor et (3) la résilience d’A. millefolium d’où l’importance de favoriser sa présence dans les friches industrielles, où celle-ci pousse déjà naturellement. / According to the MELCC’s contaminated land directory, Greater Montréal has more than 11,000 polluted sites. One approach to remediating these lands is phytoremediation, a strategy that uses plants to reduce contaminant concentrations in situ. A restraint associated with the revegetation of contaminated sites is the risk of bioaccumulation in the food chain. A solution would be using polycultures to take advantage of the combination of plant species with different functions. The main objective of this study was to compare the accumulation of trace elements of a food plant (Solanum lycopersicum—cherry tomato) and “phytoremediator” plants (Salix discolor—American pussy willow, Achillea millefolium—yarrow, Trifolium repens—white clover) when grown as companions on contaminated soils. Fifteen treatments were examined: five plant associations (cherry tomato alone, cherry tomato/yarrow, cherry tomato/white clover/yarrow, cherry tomato/discolor willow, and cherry tomato/discolor willow/white clover), as well as three soils (technosoil 110 mg Cu kg-1, technosoil spiked up to 2500 mg Cu kg-1 and uncontaminated garden soil). The results showed (1) that polycultures including T. repens were the most efficient at producing biomass and phytoextrating copper, (2) that stresses (i.e. competition and water resources) reduced the performance of S. discolor and (3) the resilience of A. millefolium and the importance of promoting its presence in brownfield sites, where it already grows naturally.

Les objectifs de la thèse sont de (i) modéliser le transport de l’eau, d’un traceur et des polluants dans les sols contaminés, (ii) étudier l’estimabilité des paramètres et les corrélations entre les paramètres, (iii) optimiser les paramètres. Les différents modèles implantés dans le logiciel HYDRUS qui permettent de rendre compte ou pas de l’écoulement préférentiel et du transport hors équilibre physique et chimique sont choisis. Les études concernant le transport d’eau dans un lysimètre de terrain ont montré que les données quotidiennes de pressions et de teneurs en eau volumique contiennent plus d’information que les données horaires, que les pressions ont plus d’information que les teneurs en eau volumique, et que les corrélations des paramètres ont fait perturber les résultats de l’optimisation. Sur le même lysimètre, l’étude d’estimabilité des paramètres caractéristiques pour le transport du traceur (bromure) a montré que les concentrations dans les solutions de percolation ne sont pas suffisantes pour estimer le paramètre de transfert de l’eau entre les zones mobile et immobile car ce paramètre est fortement corrélé avec le paramètre de transfert de soluté. Pour le transport des hydrocarbures aromatiques polycycliques (HAP) dans les colonnes de laboratoire sous différentes conditions de saturation en eau, quand le degré de transport hors équilibre chimique des HAP est élevé, les concentrations en HAP dans les solutions de percolation de la colonne non saturée contiennent plus d’information que celles dans la colonne saturée / Preferential flow and nonequilibrium transport are probably the most frustrating in terms of hampering accurate predictions of contaminant transport through the vadose zone. The mathematical description of preferential flow and nonequilibrium transport needs many parameters that are not measurable. Therefore, the inverse method is a promising way to estimate model parameters. The main objectives of this work are to (i) study the water flow using the uniform flow and dual-porosity models, tracer and contaminant transport using the uniform transport model and/or physical and chemical nonequilibrium transport models, (ii) investigate parameter estimability and correlations between different parameters, and (iii) optimize the hydraulic properties and solute transport parameters. The results concerning the water flow in the bare field lysimeter show that daily data contained much more information than hourly data, daily pressure heads contained more information than daily water contents; the correlations between different parameters hamper the optimization results strongly. Basing on the tracer concentrations in the leaching solution of the lysimeter, the first-order rate water transfer coefficient was not estimable since this parameter was highly correlated with the solute transfer coefficient. PAH concentrations in the leaching solution of the contaminated soil column under saturated and nonsaturated flow conditions show that when the degree of chemical nonequilibirum transport is high, the solute leaching of the nonsaturated column contained more information than those of the saturated column. In addition, the fraction of sites with instantaneous sorption and the linear adsorption distribution coefficient always showed a very strong correlation, they were impossible to optimize simultaneously

<p><p>The industrialization in Sweden has increased the large number of areas that have been contaminated with various types of pollution. One of those sites are the property Höjen 3:24 in Arboga where “Arboga Mekaniska Verkstad” once been. The property wants to increase the use of the old former foundry building with the adjacent “plate-workshop” and believe there are two options for the building: That the building either should be used as a warehouse/concert hall, or rebuilt into a cultural center.</p><p> </p><p>An environmental evaluation has shown that the levels of heavy metals are over the Swedish environmental protection agency guidelines of less sensitive land. The purpose of this report has been to provide possible suggestions for remedial action for these two options and to describe the effects, consequences and costs of the various proposals. It appears from the report that there are two possible solutions to reduce exposure and proliferation of heavy metal pollution in the building. If the building is used for storage and concerts then the pollution should be encapsulated, while if the building is built into a cultural center, it is suggested that the pollutants are to be removed.</p><p> </p><p>In an encapsulation it is suggested that the floor surfaces are reconstructed, the walls must be painted with an elastic paint and all the dust on the beams are to be vacuumed. In addition to the measures proposed is that the ground floor is dug up and the walls are milled down a few millimeters to remove the highest levels of pollutions. But there are some uncertainties and knowledge gaps in the report. It is mainly the economic aspect as calculated using prices from construction firms on the Internet and estimates on the building's size and degree of pollution. There are also gaps and uncertainties about the pollution distribution and dissemination of building materials, soil and groundwater.</p></p> / <p><p>Sveriges utveckling till industriland har gett upphov till att ett stort antal områden blivit förorenade med olika typer av föroreningar. Ett flertal av dessa områden har blivit så förorenade att de riskerar att skada människors hälsa och miljön. Idag har drygt 80 000 potentiellt förorenade områden kartlagts i Sverige och Arboga mekaniska verkstad är ett av dessa förorenade områden. Sverige riksdag har antagit 16 miljökvalitetsmål som ett steg i arbetet mot en hållbar utveckling. Ett av miljökvalitetsmålen är ”Giftfri miljö”. Målet innefattar ett flertal delmål, varvid två delmål behandlar ”Efterbehandling av förorenade områden”.</p><p> </p><p>I Arboga kommun, på fastigheten Höjen 3:24 har Arboga mekaniska verkstad en gång legat som är en före detta mekanisk verkstad där det har tillverkats bland annat järnvägsgods, strykjärn och manglar. Verksamheten bedrevs i ett flertal olika byggnader. På området finns idag till exempel en gammal gjuteribyggnad med angränsande plåtverkstad. Arboga mekaniska verkstad startade sin verksamhet år 1858 och år 1967 lades verksamheten i gjuteribyggnaden ned. Resterande verksamhet lades ned år 1982, när företaget gick i konkurs.  Idag används gjuteribyggnaden med angränsande plåtverkstad endast till lagerlokal.</p><p> </p><p>Med uppdrag från Länsstyrelsen i Västmanland har SGI utfört en inventering av området enligt MIFO fas 2 med statliga medel. Gjuteribyggnaden med angränsande plåtverkstad riskklassades i en MIFO fas 1 utfört av länsstyrelsen till risklass 2, stor risk. MIFO fas 2 utredningen resulterade i att byggnaden klassades ner till risklass 3, måttlig risk. Utredningen i MIFO fas 2 omfattade gjuteribyggnaden samt angränsande plåtverkstad och marken i och omkring dessa byggnader. Det påvisades förhöjda halter av föroreningar i form av tungmetallerna arsenik, koppar, zink och bly. Dessa förhöjda halter har påträffats i framförallt i det äldre sandgolvet, omkring ugnen i gjuteriet samt i marklager med slaggrester. De förhöjda halterna av koppar i området utgör inte någon hälsofara, men de kan däremot påverka markekosystemet i området. Arsenikförekomsten bedöms kunna utgöra en hälsorisk. På vissa platser i gjuteribyggnaden överskrider arsenikhalterna det hälsobaserade riktvärdet för MKM. Vid labbanalys har det visat sig att endast ett prov innehåller halter över MKM, men eftersom antalet prov är begränsat i förstudien kan det finnas fler platser med höga arsenikhalter. Undersökningen tyder på att åtgärder för att förhindra föroreningsspridning samt exponering bör utföras. I första hand bör föroreningarna tas bort och åtgärder som minskar exponeringsrisken bör övervägas i andra hand. De förhöjda metallhalterna kan begränsa markfunktionen i viss mån.</p><p> </p><p>Det finns flera olika saneringsmetoder för att behandla metallförorenad mark. Exempel på några sådana metoder är reaktiva barriärer, jordtvätt och termiska metoder, stabilisering och solidifiering, elektrokemiska metoder samt fytoremediering. För att behandla en förorenad byggnad kan flera olika metoder användas, bland annat: rivning, sanering, forcerad ventilation och inkapsling. Målning kan vara en relativt enkel metod för att kapsla in föroreningarna och minska exponeringsrisken. Syftet med detta examensarbete har varit att ge åtgärdsförslag till saneringen av gjuteribyggnaden med angränsande plåtverkstad utifrån två alternativ inklusive förslagens effekter, konsekvenser och kostnader. Alternativ ett innebär att gjuteriet med angränsande plåtverkstad fortsätter ha lagerverksamhet men i utökad form och att konserter kan anordnas i byggnaden. Detta innebär att en rad åtgärder kan behöva vidtas för att förhindra exponeringsrisken samt spridningsrisken. Byggnaden är dessutom eftersatt och kräver en viss renovering före en utökad användning. Alternativ två innebär att gjuteribyggnaden med angränsade plåtverkstad görs om till ett kulturcentrum med konserthall, museum, hantverksstäder och café. Den gamla industrikulturen ska bevaras så mycket som möjligt. Projektets framtidsversion kräver stora ekonomiska resurser och större saneringsåtgärder än alternativ ett.</p><p> </p><p>De åtgärdsalternativ som förespråkas i båda alternativen är framförallt dammsugning av bjälkar, hårdgöra golvet samt att lägga in en geotextilduk som förhindrar föroreningarnas spridning samt inkapsling av föroreningarna i väggarna i form av målning. Under själva sanerings- och renoveringsarbetet med byggnaden och marken kommer boende och djur- och växtliv inte störas i någon större omfattning, då de boende bor ca 100 meter ifrån fastigheten samt att industriverksamhet redan pågår i området. Industriverksamheten kan i dagsläget ge upphov till buller, vibrationer och andra störningar.</p><p> </p><p>De slutsatser vi kan dra från vårt arbete är att det finns två lösningar för att bevara och öka användningen av byggnaden. Det ena är alternativ ett som bygger på att byggnaden används till lagerlokal och konserthall. I det alternativet kapslas föroreningarna in. Det andra är alternativ två som går ut på att ett kulturcentrum upprättas i byggnaden. För detta alternativ avlägsnas föroreningarna. Alternativ två är ett mer långsiktigt alternativ än alternativ ett med avseende på exponeringsrisk och föroreningsspridning. Däremot är det ur ett kortsiktigt ekonomiskt perspektiv billigare att genomföra åtgärdsförslagen för alternativ ett. Den totala kostnaden som sammanställts är mycket preliminärt och osäker då endast antaganden har gjorts på byggnadens storlek samt hur mycket av jorden som behöver saneras. Det har heller inte tagits någon hänsyn till förarbeten och andra underarbeten.</p><p> </p><p>Det finns osäkerheter rörande gjuteribyggnaden med angränsande plåtverkstad som behöver utredas, främst vid alternativ två. I den gjorda MIFO fas 2 utredningen var antalet prov begränsat, därmed kan fler platser påvisa höga föroreningshalter. I utredningen fann man bland annat enstaka platser i gjuteribyggnaden där arsenikhalterna överskrider det hälsobaserade riktvärdet för MKM. Utredningen tyder på att ingen provtagning har utförts på överbyggnaden av trä. Förorenat byggmaterial är heller inte avgränsat i djup- och ytled.</p><p> </p><p>För fortsatt arbete bör förslagsvis dammet ovanpå bjälkarna i gjuteribyggnaden provtas med ett XRF-instrument först för att se om det finns något arsenik dammet. Detta ska ske enligt ett förläggande som finns från kommunens miljö- och hälsoskyddsenhet. Sedan bestäms vilket alternativ som ska genomföras. Väljs alternativ ett kan åtgärder börja vidtas direkt för att kapsla in föroreningarna. För alternativ två behövs en mer omfattande provtagning genomföras för att ta reda på föroreningsspridning samt föroreningshalter i området. Utifrån resultatet från provtagningen kan en plan för saneringen upprättas och saneringen kan sedan påbörjas, följt av ombyggnad och renovering.</p></p>

Entre las actividades potencialmente contaminantes del suelo se encuentra la industria de obtención de cinc, que, a lo largo de la historia, ha generado cantidades importantes de residuos con elevados contenidos de metales pesados depositados en las inmediaciones de sus instalaciones hasta épocas recientes. Después de la promulgación del RD 9/2005, dicha contaminación y el riesgo que conlleva deberán ser evaluados en los diferentes emplazamientos. El objetivo de esta tesis es el estudio de la movilización natural y forzada de plomo, cadmio y arsénico bajo distintas condiciones medioambientales en residuos procedentes de la hidrometalurgia del cinc y en suelos industriales contaminados por los productos de alteración de dichos residuos, así como la relación que existe entre la movilización y las características químicas y mineralógicas de los mismos, ya que el conocimiento de estos materiales y de las condiciones de movilización de los metales estudiados puede ayudar al estudio metodológico de evaluación de la contaminación así como al análisis de riesgos que permita la toma de decisiones ante la posible recuperación de tales terrenos. / Among the industries that mar be considered potential contaminators of the soil is that dedicated to obtaining zinc, which, during its time, has generated substantial quantities ofheavy metal-containing wastes which, until recently, were simply dumped in the irnmediate environs. Following the Spanish law RD 9/2005, the resulting contamination and any associated risks have to be evaluated. The object ofthis thesis was to study the natural and forced mobilization oflead, cadmium and arsenic in a variety of environmental conditions in wastes resulting from the zinc hydrometallurgy indus1ry and in soils contaminated by fue alteration products of these wastes, together with fue relation between such mobilization and fue chemical and mineralogical characteristics of the same. Knowledge of these material s and of the metal mobilization conditions studied will help in the methodological study of contamination evaluation and in the analysis of risks. The findings will, it is hoped, help in the making decisions that need to be taken to recover the affected soils.

The industrialization in Sweden has increased the large number of areas that have been contaminated with various types of pollution. One of those sites are the property Höjen 3:24 in Arboga where “Arboga Mekaniska Verkstad” once been. The property wants to increase the use of the old former foundry building with the adjacent “plate-workshop” and believe there are two options for the building: That the building either should be used as a warehouse/concert hall, or rebuilt into a cultural center.   An environmental evaluation has shown that the levels of heavy metals are over the Swedish environmental protection agency guidelines of less sensitive land. The purpose of this report has been to provide possible suggestions for remedial action for these two options and to describe the effects, consequences and costs of the various proposals. It appears from the report that there are two possible solutions to reduce exposure and proliferation of heavy metal pollution in the building. If the building is used for storage and concerts then the pollution should be encapsulated, while if the building is built into a cultural center, it is suggested that the pollutants are to be removed.   In an encapsulation it is suggested that the floor surfaces are reconstructed, the walls must be painted with an elastic paint and all the dust on the beams are to be vacuumed. In addition to the measures proposed is that the ground floor is dug up and the walls are milled down a few millimeters to remove the highest levels of pollutions. But there are some uncertainties and knowledge gaps in the report. It is mainly the economic aspect as calculated using prices from construction firms on the Internet and estimates on the building's size and degree of pollution. There are also gaps and uncertainties about the pollution distribution and dissemination of building materials, soil and groundwater. / Sveriges utveckling till industriland har gett upphov till att ett stort antal områden blivit förorenade med olika typer av föroreningar. Ett flertal av dessa områden har blivit så förorenade att de riskerar att skada människors hälsa och miljön. Idag har drygt 80 000 potentiellt förorenade områden kartlagts i Sverige och Arboga mekaniska verkstad är ett av dessa förorenade områden. Sverige riksdag har antagit 16 miljökvalitetsmål som ett steg i arbetet mot en hållbar utveckling. Ett av miljökvalitetsmålen är ”Giftfri miljö”. Målet innefattar ett flertal delmål, varvid två delmål behandlar ”Efterbehandling av förorenade områden”.   I Arboga kommun, på fastigheten Höjen 3:24 har Arboga mekaniska verkstad en gång legat som är en före detta mekanisk verkstad där det har tillverkats bland annat järnvägsgods, strykjärn och manglar. Verksamheten bedrevs i ett flertal olika byggnader. På området finns idag till exempel en gammal gjuteribyggnad med angränsande plåtverkstad. Arboga mekaniska verkstad startade sin verksamhet år 1858 och år 1967 lades verksamheten i gjuteribyggnaden ned. Resterande verksamhet lades ned år 1982, när företaget gick i konkurs.  Idag används gjuteribyggnaden med angränsande plåtverkstad endast till lagerlokal.   Med uppdrag från Länsstyrelsen i Västmanland har SGI utfört en inventering av området enligt MIFO fas 2 med statliga medel. Gjuteribyggnaden med angränsande plåtverkstad riskklassades i en MIFO fas 1 utfört av länsstyrelsen till risklass 2, stor risk. MIFO fas 2 utredningen resulterade i att byggnaden klassades ner till risklass 3, måttlig risk. Utredningen i MIFO fas 2 omfattade gjuteribyggnaden samt angränsande plåtverkstad och marken i och omkring dessa byggnader. Det påvisades förhöjda halter av föroreningar i form av tungmetallerna arsenik, koppar, zink och bly. Dessa förhöjda halter har påträffats i framförallt i det äldre sandgolvet, omkring ugnen i gjuteriet samt i marklager med slaggrester. De förhöjda halterna av koppar i området utgör inte någon hälsofara, men de kan däremot påverka markekosystemet i området. Arsenikförekomsten bedöms kunna utgöra en hälsorisk. På vissa platser i gjuteribyggnaden överskrider arsenikhalterna det hälsobaserade riktvärdet för MKM. Vid labbanalys har det visat sig att endast ett prov innehåller halter över MKM, men eftersom antalet prov är begränsat i förstudien kan det finnas fler platser med höga arsenikhalter. Undersökningen tyder på att åtgärder för att förhindra föroreningsspridning samt exponering bör utföras. I första hand bör föroreningarna tas bort och åtgärder som minskar exponeringsrisken bör övervägas i andra hand. De förhöjda metallhalterna kan begränsa markfunktionen i viss mån.   Det finns flera olika saneringsmetoder för att behandla metallförorenad mark. Exempel på några sådana metoder är reaktiva barriärer, jordtvätt och termiska metoder, stabilisering och solidifiering, elektrokemiska metoder samt fytoremediering. För att behandla en förorenad byggnad kan flera olika metoder användas, bland annat: rivning, sanering, forcerad ventilation och inkapsling. Målning kan vara en relativt enkel metod för att kapsla in föroreningarna och minska exponeringsrisken. Syftet med detta examensarbete har varit att ge åtgärdsförslag till saneringen av gjuteribyggnaden med angränsande plåtverkstad utifrån två alternativ inklusive förslagens effekter, konsekvenser och kostnader. Alternativ ett innebär att gjuteriet med angränsande plåtverkstad fortsätter ha lagerverksamhet men i utökad form och att konserter kan anordnas i byggnaden. Detta innebär att en rad åtgärder kan behöva vidtas för att förhindra exponeringsrisken samt spridningsrisken. Byggnaden är dessutom eftersatt och kräver en viss renovering före en utökad användning. Alternativ två innebär att gjuteribyggnaden med angränsade plåtverkstad görs om till ett kulturcentrum med konserthall, museum, hantverksstäder och café. Den gamla industrikulturen ska bevaras så mycket som möjligt. Projektets framtidsversion kräver stora ekonomiska resurser och större saneringsåtgärder än alternativ ett.   De åtgärdsalternativ som förespråkas i båda alternativen är framförallt dammsugning av bjälkar, hårdgöra golvet samt att lägga in en geotextilduk som förhindrar föroreningarnas spridning samt inkapsling av föroreningarna i väggarna i form av målning. Under själva sanerings- och renoveringsarbetet med byggnaden och marken kommer boende och djur- och växtliv inte störas i någon större omfattning, då de boende bor ca 100 meter ifrån fastigheten samt att industriverksamhet redan pågår i området. Industriverksamheten kan i dagsläget ge upphov till buller, vibrationer och andra störningar.   De slutsatser vi kan dra från vårt arbete är att det finns två lösningar för att bevara och öka användningen av byggnaden. Det ena är alternativ ett som bygger på att byggnaden används till lagerlokal och konserthall. I det alternativet kapslas föroreningarna in. Det andra är alternativ två som går ut på att ett kulturcentrum upprättas i byggnaden. För detta alternativ avlägsnas föroreningarna. Alternativ två är ett mer långsiktigt alternativ än alternativ ett med avseende på exponeringsrisk och föroreningsspridning. Däremot är det ur ett kortsiktigt ekonomiskt perspektiv billigare att genomföra åtgärdsförslagen för alternativ ett. Den totala kostnaden som sammanställts är mycket preliminärt och osäker då endast antaganden har gjorts på byggnadens storlek samt hur mycket av jorden som behöver saneras. Det har heller inte tagits någon hänsyn till förarbeten och andra underarbeten.   Det finns osäkerheter rörande gjuteribyggnaden med angränsande plåtverkstad som behöver utredas, främst vid alternativ två. I den gjorda MIFO fas 2 utredningen var antalet prov begränsat, därmed kan fler platser påvisa höga föroreningshalter. I utredningen fann man bland annat enstaka platser i gjuteribyggnaden där arsenikhalterna överskrider det hälsobaserade riktvärdet för MKM. Utredningen tyder på att ingen provtagning har utförts på överbyggnaden av trä. Förorenat byggmaterial är heller inte avgränsat i djup- och ytled.   För fortsatt arbete bör förslagsvis dammet ovanpå bjälkarna i gjuteribyggnaden provtas med ett XRF-instrument först för att se om det finns något arsenik dammet. Detta ska ske enligt ett förläggande som finns från kommunens miljö- och hälsoskyddsenhet. Sedan bestäms vilket alternativ som ska genomföras. Väljs alternativ ett kan åtgärder börja vidtas direkt för att kapsla in föroreningarna. För alternativ två behövs en mer omfattande provtagning genomföras för att ta reda på föroreningsspridning samt föroreningshalter i området. Utifrån resultatet från provtagningen kan en plan för saneringen upprättas och saneringen kan sedan påbörjas, följt av ombyggnad och renovering.

The aim of the thesis has been to evaluate and understand the effect of caustic alkali solution of varying composition on the behaviour of expansive soil containing mixed layered minerals. Mixed layered minerals are formed of two or more kinds of inter grown layers, not physical mixtures. Illite - smectite is the most abundant and wide spread of the mixed layered clay minerals in sedimentary rocks and soils and also more common than either discrete illite or smectite. In geotechnical engineering much attention has not been paid to the behaviour of soils containing mixed layered minerals. Much less is known about the behaviour of these soils in polluted environment. Mixed layered minerals are more susceptible to environmental changes as the structural linkages between the layer minerals are weak compared to normal layered phyllosilicates. One important pollutant that can have considerable effect on the behaviour of soils is the caustic alkali contamination released from various industries. Recent studies have shown that the behaviour of even stable minerals is affected by alkali contamination. However, the effect of caustic alkali contamination on the behaviour of soils containing mixed layered minerals is not known and has been chosen for detailed study. Also to understand the mechanism of their interaction with alkali, it is necessary to study the effect of alkali solutions on the constituent clay minerals viz., montmorillonite and illite under similar conditions. To elucidate the mechanism of soil alkali interaction limited tests were conducted with simple electrolyte solution, as the alkali solution also acts as electrolyte apart from being alkaline. To confirm the mechanism of interaction, tests are also conducted on these soils with industrial spent liquor containing high caustic alkali and suspended alumina obtained from an alumina extraction plant treating bauxite with high alkali solutions at high temperatures. The results obtained in the laboratory are compared with the soil samples contaminated with leaking industrial Bayer's liquid in the field. Studies are also conducted to suggest remedial measures to control the adverse effects of alkali solutions on soil containing mixed layer minerals. The content of the thesis is broadly divide into 8 Chapters - viz., Introduction, Background and overview, Experimental program and procedures, Behaviour of soils containing mixed layer mineral illite - smectite (BCSI), Behaviour of montmorillonite and illite, Influence of Bayer's liquor and study on the field contaminated soils, Measures to control the influence of alkali contamination on BCSI and Summary and conclusions. The broad outline of these chapters is given in Chapter 1. A review of literature on the behaviour of soils containing different types of clay minerals with emphasis on mixed layer minerals has been presented in Chapter 2. The influence of different inorganic contaminants on the properties of soils in terms of their physical and chemical characteristics as well as their concentration has been summarized. The importance of changes in surface characteristics of soil particles and the changes in the thickness of diffuse double layer in altering the property of soils at low concentration of contaminants and changes in the mineralogy with high concentrated contaminants such as acids and alkalis has been highlighted. This forms the background information necessary to bring out the scope of the study. Four soils having different mineralogy have been used in this study. These soils are, black cotton soil containing predominantly mixed layer mineral illite - smectite mineral called rectorite, illite, montmorillonite (common smectite) and black cotton soil containing predominantly montmorillonite. The properties of the soils used are described in Chapter 3. Caustic alkali solutions of 1N, 4N concentration prepared in the laboratory and industrial alkali-spent liquor are used as contaminants. The spent Bayer's liquor had about 4N alkali concentration and 10% alumina in suspension. To simulate the effect of suspended alumina, two more caustic alkali solutions of 1N and 4N solutions containing 10% alumina by weight of solutions are also prepared. To isolate the effect of electrolyte solutions from that of alkali solution, two electrolyte solutions of 1N and 4N sodium chloride solutions are also used. Test procedures for conducting various tests such as pH, water adsorption characteristics, X-ray diffraction studies, SEM studies, thermal characteristics and geotechnical properties such as Atterberg limits, Oedometer tests and Shear Strength are given in this chapter. The test procedures are modified, wherever necessary, to bring out the effect of contaminants, particularly the effect of duration of interaction on the properties of soils. The source and properties of black cotton soil are presented in Chapter 4. Detailed x-diffraction studies have confirmed the presence of inter layered illite-smectite mineral viz., rectorite, which is uncommon in Indian expansive soils, and is classified as CH (Clay of high compressibility) as per ASTM soil classification. Effect of alkali and salt solutions of 1N and 4N concentration on all physico chemical and geotechnical properties are studied in this chapter. As it is known that presence of certain elements such as aluminium influence the soil alkali interaction, the effect of suspended alumina along with alkali solution has also been investigated. The effect of contaminating fluids such as 1N NaOH, 4N NaOH with and without alumina, 1N NaCl and 4N NaCl on the geotechnical properties of the soil has been studied. Mineralogical changes were observed by XRD and thermal studies in the soil treated with 4N NaOH solution and 4N NaOH + 10% alumina. The interlayer potassium of illite is released and potassium hydroxide is formed in soil treated with 4N NaOH. Swelling compounds such as sodium aluminium silicate hydroxide hydrate (SASH) has formed due to attack of 4N NaOH + 10% alumina on silica rather than on rectorite. Thus the studies clearly bring out that the rectorite present in the soil is dissociated only in the presence of strong alkali solutions of concentration of about 4N. The liquid limit of soil decreased with increase in the electrolyte concentration in the case of NaCl solutions. With 1N NaOH, the liquid limit of soil increased due to increase in the thickness of diffuse double layer due to increased pH. However, Proctor's maximum dry density increased and optimum moisture content decreased with 1N NaOH. With increase in the concentration of alkali solution to 4N, the rectorite dissociates into constituent minerals with the formation potassium hydroxide. The liquid limit of soil decreased probably due to the dominating influence of electrolyte nature of hydroxide solution over the effect of increased negative charge on clay particles due increase in the pH on the constituent minerals. Proctor's maximum dry density decreased and optimum moisture content increased with 4N NaOH. Sediment volume and oedometer free swell at seating/nominal surcharge load of 6.25 kPa of soil increased in 1N and 4N caustic alkali solutions, though by different mechanisms. The increase with 1N solution is essentially due to increased negative charges on clay mineral surface. However, the increase in swelling with 4N solution is associated with the dissociation of rectorite mineral and occurs in two distinct phases unlike in the case of 1N solution. While the first phase can be attributed to the effect of alkaline nature of the solution after reduction in its concentration due to reaction with rectorite and the consequent reduction in its electrolyte nature. The second phase is due to the swelling of the separated constituent minerals in the presence of excess of alkali and occurs after much delay. Consolidation behaviour of rectorite in 1N and 4N alkali solutions has been studied in two ways: 1). Loading without waiting for the second stage of swelling to occur, as in standard consolidation procedure and 2). Loading after completion of second stage of swelling which is occurring after considerable delay as explained earlier. Normally one would initiate loading after equilibrium is reached at the end of first stage of swelling and second stage of swelling is not suspected. As there is no second stage of swelling with 1N solutions, these two types of consolidation tests produced the same results. Abnormal rebound is observed during unloading with 4N solution in which loading cycle is initiated without waiting for second stage of swelling to complete. It is interesting to note that while the liquid limit of soil decreased with increase in the concentration of alkali solution, the swelling increased. The testing procedure and period of interaction as well as the concentration of alkali solution during the test in these two tests are different. The effects of alkali solution are more severe in case of liquid limit because of thorough mixing and consequent effective reaction during testing. Similarly, the volume changes in soil that has already reacted with 4N alkali solution when exposed to further to alkali contamination are considerably less compared to uncontaminated soil exposed to fresh contamination. The shear strength of soil treated with 4N-alkali solution has increased particularly after long period of interaction. This indicates that the soil after mineralogical changes posses good strength. Chapter 5 presents the effect of alkali and salt solutions on the physico chemical and geotechnical properties of component minerals of mixed layered illite/smectite. For this study, commercially obtained montmorillonite (bentonite), naturally occurring black soil containing montmorillonite and commercially pure illite are used. It was observed that montmorillonite alkali reactions would not produce significant mineralogical changes where as illite is dissociated into smectite with the formation of potassium silicate by the interaction of released potassium with soluble silica. This confirms that the ultimate products of rectorite with alkali solutions would be smectite and compounds of potassium. In the absence of mineralogical alterations the liquid limit of montmorillonite decreases due to suppression of diffuse double layer thickness due to dominating influence of alkali solutions on this highly active clay. However a small increase in liquid limit is observed in illite with alkali solutions. Thus the net effect of alkali on rectorite is to decrease the liquid limit with increase in alkali concentration. While the free swell and oedometer swelling of montmorillonite generally decreases with increase in the alkali concentration, they increase in illite. However, in both the minerals the swelling occurs only in one phase. Thus the second phase of swelling that has been observed in rectorite can be attributed to delayed swelling of montmorillonite that has been released by the attack of alkali on rectorite. The behaviour of black soil containing mixed layer mineral contaminated in the field and laboratory by leaking Bayer's spent liquor in an alumina extraction plant has been studied in Chapter 6. The Atterberg limits of the samples treated with liquor are reduced and sediment volume increased. Similarly the swelling at seating load in consolidation test is higher in sample compacted with water and inundated with liquor. X-ray diffraction studies showed that the mineralogical changes are similar to those occurred with 4N caustic alkali solution. The mineralogical and micro structural changes in the soil samples that are contaminated by leaked spent liquor in the field are relatively more marked. Also the behavior of highly montmorillonite clay, bentonite, has been studied contaminated with liquor in the laboratory. The study on the effect of high concentrated alkali solutions on montmorillonite can be useful to study the effect of interaction on the dissociated montmorillonite. These studies are helpful to suggest some possible remedial measures to control the adverse effect of alkali on soils. Possible Remedial schemes that can be adopted before and after contamination of the soil to control the adverse effect of alkali solutions on the black cotton soil containing mixed layered mineral are listed and their effectiveness examined in Chapter 7. The suggested remedial measures include flushing with water to dilute the effect of alkali, neutralisation with dilute hydrochloric acid, stabilisation of soil with lime and calcium chloride and use of impervious membrane to separate the foundation soil from alkali solution. The effectiveness of different measures as well as the method of their application has been described. Efforts are made to understand the mechanism of remedial action. Consolidation tests conducted on soil contaminated with 4N alkali solution and inundated with water showed increased swelling due to dilution of the alkali concentration. Though the swelling of contaminated soil can be controlled by passing dilute hydrochloric acid (1N), the method is not advocated as it can lead to ground water contamination. Mixing the soil with solutions containing up to 5% by weight of calcium compound in water could not prevent the alkali induced heave in the long run when inundated with 4N alkali solution. This was due to dissolution of silica by the strong alkali solutions and formation of swelling compounds such as sodium aluminium silicate hydroxide hydrate (SASH). The formation of sodium aluminates occurred only when the alkali solution contained alumina or soil contained calcium compounds. There are no significant variations in the effects of calcium chloride or calcium hydroxide on contaminated soil. Replacing the foundation soil with soil thoroughly contaminated with 4N alkali solutions and controlling the migration of contaminants into the foundation soil using high-density polyethylene (HDPE) geosynthetic membranes can be an effective measure to control the heaving in alkali contaminated foundation soil containing interstratified illite – smectite. Summary and the major conclusions of the thesis are presented in Chapter 8.