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  • 101.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Ramanathan, Alagappan
    School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
    Mukherjee, Arun B.
    Helsinki University Environmental Research Centre, Finland.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Chandrashekharam, Dornadula
    Indian Institute of Technology-Bombay, Mumbai-400076, India.
    Groundwater and Sustainable Development: Problems, Perspectives and Challenges2008Book (Refereed)
    Abstract [en]

    Groundwater is the most important source of domestic, industrial, and agricultural water and also a finite resource. Population growth has created an unprecedented demand for water, with the situation most critical in the developing world, where several million people depend on contaminated groundwater for drinking purposes. Geogenic contaminants, such as arsenic and fluoride at toxic levels, pose major environmental risks and endanger public health. This book is a collection of papers providing a multi-disciplinary overview for scientists and professionals involved in the sustainable development of groundwater resources.

  • 102.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Shi, Fei
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Sracek, O
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Bundschuh, J
    Groundwater characteristics in the shallow aquifers of Huhhot region in Inner Mongolia, PR China: Implications on the mobilisation of arsenic2006In: Natural Arsenic in Groundwaters of Latin America: Abstract Volume / [ed] Bundschuh, J., Armienta, M.A., Bhattacharya, P., Matschullat, J., Birkle, P., Rodríguez, R., 2006, p. 11-12Conference paper (Other academic)
    Abstract [en]

    Elevated arsenic (As) concentration ingroundwater is becoming a worldwide problem. In Huhhot Alluvial Basin (HAB) in 

    Inner Mongolia, People’s Republic ofChina, a population of over a million isexposed to severe health risk due to theconsumption of groundwater with high Asconcentration. In some arsenic seriouslyaffected areas, As concentration reach 1491µg L-1, 149 times over WHO’s drinkingwater guideline value for As and exceed theChinese drinking water standard by a factorof 30 times. Due to the acute shortage ofsafe water supply and inefficient watermanagement system, people are compelledto drink groundwater with high As concentration. Long period ingestion of water withhigh As concentration have lead to chronicarsenic poisoning among the residents ofthe region. This present work deals with thehydrogeochemical characterisation of thegroundwater of the shallow alluvial aquifers and their implications on the chemistryand its relation to the mechanism of Asmobilization in the HAB.Groundwater samples were collected during October 2003, from 29 sites in the village of Tie Men Jing, located about 100 kmfrom Inner Mongolia’s capital Huhhot. ThepH, redox potential (Eh), temperature andelectrical conductivity were measured atsites while major ions, trace elements including As total and As (III) were analyzedin laboratories at the Royal Institute ofTechnology and Stockholm University inSweden. Groundwater is generally neutralto alkaline and the pH varies from 6.67 to8.7. The redox potential (Eh) lies between74 and 669 mV. The electrical conductivity(EC) range varies from 581 to 5200 µS cm-1. Temperature ranges from 9.1 to 13.5 °C.Depths of wells are from 4 m to 75 m.Groundwater is mostly of Na-Mg-HCO3-Cl-type and dominated by HCO3-and Cl-asthe predominant anions. The concentrationsof SO42-range between 0.3 and 172.8 mg L-1and there is a trend of decreasing sulfateconcentrations with increase in well depth.The levels of NO3-were lower than theWHO´s guideline value of 50 mg L-1in 27wells. These high NO3-concentrations 

    could have been caused by anthropogeniccontamination due to the sanitation practices.The PO43-concentration ranges between 0.04to 2.6 mg L-1.Total As concentration ranged from belowdetect limit (5.2 µg L-1) to 141 µg L-1. In 28of the investigated wells, As levels exceededWHO’s guideline value 10 µg L-1and 17wells exceeded Chinese standard 50 µg L-1.Among the 42 groundwater samples of theshallow aquifers only three complied withthe WHO drinking water guideline value forAs. The dominant species in the groundwaterwas As (III). In the 29 wells of Tie MenJing, the concentration of Fe and Mn –exceeded the WHO’s guideline value by afactor of 10.The aquifers are composed of Quaternary(mainly Holocene) fluvial and lacustrinesediments. High As occurring in anaerobicgroundwater in low-lying areas is associatedwith high concenrations of dissolved Fe andMn. Improved water supply system, employment new water and energy resources,poverty fighting and expertise cooperationare recommended to solve Huhhot basinrural area’s drinking water problem.

  • 103.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Sracek, Ondra
    Eldvall, Björn
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Asklund, Ragnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Barmen, Gerhard
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Koku, John
    Gustafsson, Jan-Erik
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Management.
    Singh, Nandita
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Management.
    Balfors, Berit Brokking
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Hydrogeochemical study on the contamination of water resources in a part of Tarkwa mining area, Western Ghana2012In: Journal of African Earth Sciences, ISSN 1464-343X, Vol. 66-67, p. 72-84Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the groundwater chemistry with special concern to metal pollution in selected communities in the Wassa West district, Ghana. In this mining area, 40 ground water samples, mainly from drilled wells, were collected. The groundwaters have generally from neutral to acidic pH values and their Eh values indicate oxidising conditions. The dominating ions are calcium, sodium, and bicarbonate. The metal concentrations in the study area are generally lower than those typically found in mining regions. Only 17 wells show metal concentrations exceeding WHO guidelines for at least one metal. The main contaminants are manganese and iron, but arsenic and aluminium also exceed the guidelines in some wells probably affected by acid mine drainage (AMD). Metal concentrations in the groundwater seem to be controlled by the adsorption processes. Hydrogeochemical modelling indicates supersaturation of groundwater with respect to several mineral phases including iron-hydroxides/oxides, suggesting that adsorption on these minerals may control heavy metal and arsenic concentrations in groundwater. The area is hilly, with many groundwater flow divides that result in several local flow systems. The aquifers therefore are not strongly affected by weathering of minerals due to short groundwater residence times and intense flushing. The local character of groundwater flow systems also prevents a strong impact of acid mine drainage on groundwater systems in a regional scale.

  • 104.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, M.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Hasan, M.A.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Ahmed, K.M.
    Sracek, O.
    Jakariya, M.
    Huq, S.M.I.
    Naidu, R.
    Smith, E.
    Owens, G.
    Arsenic mobilisation in the Holocene flood plains in South-central Bangladesh: Evidences from the hydrogeochemical trends and modeling results2008In: Groundwater for Sustainable Development: Problems, Perspectives and Challenges / [ed] Bhattacharya, P., Ramanathan, AL., Mukherjee A.B., Bundschuh, J., Chandrasekharam, D. Keshari, A.K., The Netherlands: Taylor and Francis/A.A. Balkema , 2008, p. 283-299Chapter in book (Refereed)
  • 105.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, M.
    Jakariya, M.
    Hasan, M. A.
    Ahmed, K. M.
    Jonsson, L.
    Lundell, L.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Arsenic-safe aquifer as sustainable source of drinking water supply: A case study from Matlab thana in Southeast Bangladesh2005In: Abstract Volume, The 15th Stockholm Water Symposium: Drainage Basin Management- Hard and Soft Solutions in Regional Development, 2005, p. 143-144Conference paper (Other academic)
  • 106.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jakariya, Md
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Hasan, M.
    Ahmed, K. M.
    Ramanathan, A.
    Chandrashekharam, D.
    Mahanta, Chandan
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Husain, V.
    Targeting safe aquifers in regions with high arsenic groundwater in South Asia: Options for sustainable drinking water supply2006In: Abstract Volume-International Conference on Arsenic Contamination in Tropics (ICACT-2007) / [ed] Patel K.S., 2006, p. 18-21Conference paper (Other academic)
  • 107.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Welch, Alan H.
    Stollenwerk, Kenneth G.
    McLaughlin, Mike J.
    Bundschuh, Jochen
    Panaullah, G.
    Arsenic in the environment: Biology and Chemistry2007In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 379, no 03-feb, p. 109-120Article, review/survey (Refereed)
    Abstract [en]

    Arsenic (As) distribution and toxicology in the environment is a serious issue, with millions of individuals worldwide being affected by As toxicosis. Sources of As contamination are both natural and anthropogenic and the scale of contamination ranges from local to regional. There are many areas of research that are being actively pursued to address the As contamination problem. These include new methods of screening for As in the field, determining the epidemiology of As in humans, and identifying the risk of As uptake in agriculture. Remediation of As-affected water supplies is important and research includes assessing natural remediation potential as well as phytoremediation. Another area of active research is on the microbially mediated biogeochemical interactions of As in the environment. In 2005, a conference was convened to bring together scientists involved in many of the different areas of As research. In this paper, we present a synthesis of the As issues in the light of long-standing research and with regards to the new findings presented at this conference. This contribution provides a backdrop to the issues raised at the conference together with an overview of contemporary and historical issues of As contamination and health impacts. Crown

  • 108. Bhowmick, S.
    et al.
    Nath, B.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Chakraborty, S.
    Chatterjee, D.
    Groundwater arsenic chemistry and redox process comparison in three physiographic settings of deltaic West Bengal, India2012In: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment, 2012, p. 54-56Conference paper (Refereed)
    Abstract [en]

    A comparative hydrogeochemical study was carried out in West Bengal covering three physiographic settings of deltaic floodplains to demonstrate the control of geogenic and anthropogenic influences on groundwater arsenic (As) mobilization. The low redox potential (Eh = -185 to -86 mV) and the presence of low sulfate (SO 4 2-) and high Dissolved Organic Carbon (DOC), phosphate (PO 4 3-) and bicarbonate) (HCO 3 -) concentrations in groundwater signifies microbially mediated redox processes controlling As release in the aquifer. The release of As is influenced by both geogenic (i.e. geomorphology and/or landform features) and anthropogenic (i.e. unsewered sanitation and domestic wastes) factors.

  • 109. Bhowmick, Subhamoy
    et al.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Kundu, Amit Kumar
    Saha, Debasree
    Iglesias, Monica
    Nriagu, Jerome
    Mazumder, Debendra Nath Guha
    Roman-Ross, Gabriela
    Chatterjee, Debashis
    Is Saliva a Potential Biomarker of Arsenic Exposure?: A Case-Control Study in West Bengal, India2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 7, p. 3326-3332Article in journal (Refereed)
    Abstract [en]

    Saliva is a biological fluid that has not been used extensively as a biomonitoring tool in epidemiological studies. This study presents the arsenic (As) concentrations in saliva and urine samples collected from populations of West Bengal, India who had been previously exposed to high As levels in their drinking water. We found a significant (p < 0.05) association between the Log transformed Daily Ingestion of As (mu g day(-1)) and the As concentration in saliva (r = 0.68). Additionally, As concentration of saliva and urine also had a significant positive correlation (r = 0.60, p < 0.05). Male participants, smokers, and cases of skin lesion were independently and significantly associated with an increase in salivary As. Thus our findings show that saliva is a useful biomarker of As exposure in the study population. The study also advocates that measurement of the forms of As in saliva may additionally provide insight into the internal dose and any individual differences in susceptibility to As exposure.

  • 110.
    Billersjö, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    In-situ remediation of benzene-contaminated groundwater – A bench-scale study.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the construction of the new urban area in the north-eastern part of Stockholm, Stockholm Royal Seaport, groundwater with extremely elevated levels of the carcinogenic aromatic hydrocarbon benzene was discovered in the area Hjorthagen. Such a contamination can be remediated in-situ by the use of chemical oxidation and biodegradation. Due to the fact that many factors such as contaminant composition, groundwater characteristics and temperature vary between sites, smaller bench scale studies are usually conducted before the full scale remediation on site. Little published research exists on the ability of these remediation techniques in areas with lower groundwater temperature such as Stockholm, why the need of a bench-scale study in this case is even larger.

    The objective of this master thesis is to, out of three investigated remediation agents, find the most suitable one for remediation of the benzene-contaminated groundwater in Hjorthagen. This was made in the form of a bench-scale study and the techniques studied were chemical oxidation, for which the two agents hydrogen peroxide (uncatalyzed and catalyzed in the form of Fenton’s reagent) and persulfate (activated with iron (II)) were used, and biological degradation by the use of a calcium peroxide-based compound. The study showed that the benzene-contaminated groundwater was best remediated with Fenton’s reagent, which was able to degrade the benzene with great success.

  • 111.
    Billersjö, Sofia
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Sondal, Jannike
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Restaurering av Mörtsjön - en del av Åkerströmmens avrinningsområde.2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Till följd av läckage av närsalter har Östersjön idag allvarliga problem med övergödning. Åkerströmmens avrinningsområde bidrar till detta, varför en undersökning om restaure-ringsmetoder i avrinningsområdet är intressant. Syftet med detta kandidatarbete är därför att utreda möjliga restaureringsmetoder för Mörtsjön, vilken ligger inom avrinningsområdet.

    Mörtsjöns ytvattennivå sänktes för drygt 100 år sedan, vilket medfört att sjön idag är kraftigt igenvuxen och i behov av restaurering. Provtagningar visar att Mörtsjön snarare är en när-saltskälla än mer önskvärt en närsaltsfälla och att omsättningstiden i sjön är för kort för att ämnen som fosfor och kväve ska hinna sedimentera.

    Tre olika restaureringsmetoder studeras; muddring, fångdamm för fosfor och dämning, vilka skulle kunna förändra Mörtsjön till en närsaltfälla. Dessa metoder jämförs även med nollal-ternativet. Resultatet visar att muddring är den metod som lämpar sig bäst för att komma till bukt med Mörtsjöns problematik.

  • 112.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Nath, B.
    Mukherjee, A.
    Kundu, A. K.
    Mandal, U.
    Chatterjee, D.
    Potentiality of shallow brown sand aquifers as an alternative safe drinking water source in Bengal Basin2012In: Understanding the Geological and Medical Interface of Arsenic, As 2012 - 4th International Congress: Arsenic in the Environment, 2012, p. 67-68Conference paper (Refereed)
    Abstract [en]

    The present study investigated the regional distribution of brown sand aquifers (BSA) as well as their hydrogeochemical contrast to grey sand aquifers (GSA). The data indicated that in BSA redox status is limited to the Mn oxides reduction stage, while in GSA, Fe oxides reduction to SO 4 2- reduction processes are prevalent. Though, the concentration of dissolved As was very low (&lt;10 ÎŒg/L) in BSA, the concentration of Mn was very high (&gt;400 ÎŒg/L). Whereas in GSA, the enrichment patterns of As and Mn were opposite to that of BSA. This study suggests that underlying health risk of Mn in drinking water needs to be addressed more rigorously before advocating for mass scale exploitation of BSA as an alternative drinking water source despite of significantly low As concentration in groundwater.

  • 113.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Majumder, Santanu
    Neidhardt, Harald
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhowmick, Subhamoy
    Mukherjee-Goswami, Aishwarya
    Kundu, Amit
    Saha, Debasree
    Berner, Zsolt
    Chatterjee, Debashis
    Groundwater chemistry and redox processes: Depth dependent arsenic release mechanism2011In: APPLIED GEOCHEMISTRY, 2011, Vol. 26, no 4, p. 516-525Conference paper (Refereed)
    Abstract [en]

    Patchy occurrences of elevated As are often encountered in groundwater from the shallow aquifers (<50 m) of the Bengal Delta Plain (BDP). A clear understanding of various biogeochemical processes, responsible for As mobilization, is very important to explain this patchy occurrence and thus to mitigate the problem. The present study deals with the periodical monitoring of groundwater quality of five nested piezometeric wells between December 2008 and July 2009 to investigate the temporal changes in groundwater chemistry vis-a-vis the prevalent redox processes in the aquifer. Geochemical modeling has been carried out to identify key phases present in groundwater. A correlation study among different aqueous redox parameters has also been performed to evaluate prevailing redox processes in the aquifer. The long term monitoring of hydrochemical parameters in the multilevel wells together with hydrogeochemical equilibrium modeling has shown more subtle differences in the geochemical environment of the aquifer, which control the occurrence of high dissolved As in BDP groundwater. The groundwater is generally of Ca-HCO3 type. The dissolved As concentration in groundwater exceeded both WHO and National drinking water standard (Bureau of Indian Standards; BIS, 10 mu g L-1) throughout the sampling period. The speciation of As and Fe indicate persistent reducing conditions within the aquifer [As(III): 87-97% of As-T and Fe(II): 76-96% of Fe-T]. The concentration of major aqueous solutes is relatively high in the shallow aquifer (wells A and B) and gradually decreases with increasing depth in most cases. The calculation of SI indicates that groundwater in the shallow aquifer is also relatively more saturated with carbonate minerals. This suggests that carbonate mineral dissolution is possibly influencing the groundwater chemistry and thereby controlling the mobilization of As in the monitored shallow aquifer. Hydrogeochemical investigation further suggests that Fe and/or Mn oxyhydroxide reduction is the principal process of As release in groundwater from deeper screened piezometric wells. The positive correlations of U and V with As. Fe and Mn indicate redox processes responsible for mobilization of As in the deeper screened piezometric wells are possibly microbially mediated. Thus, the study advocates that mobilization of As is depth dependent and concentrations of As in groundwater depends on single/combined release mechanisms.

  • 114.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Nath, Bibhash
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Kundu, Amit K.
    Mandal, Ujjal
    Mukherjee, Abhijit
    Chatterjee, Debashis
    Mörth, Carl-Magnus
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Hydrogeochemical contrast between brown and grey sand aquifers in shallow depth of Bengal Basin: Consequences for sustainable drinking water supply2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 431, p. 402-412Article in journal (Refereed)
    Abstract [en]

    Delineation of safe aquifer(s) that can be targeted by cheap drilling technology for tubewell (TW) installation becomes highly imperative to ensure access to safe and sustainable drinking water sources for the arsenic (As) affected population in Bengal Basin. This study investigates the potentiality of brown sand aquifers (BSA) as a safe drinking water source by characterizing its hydrogeochemical contrast to grey sand aquifers (GSA) within shallow depth (<70 m) over an area of 100 km(2) in Chakdaha Block of Nadia district, West Bengal, India. The results indicate that despite close similarity in major ion composition, the redox condition is markedly different in groundwater of the two studied aquifers. The redox condition in the BSA is delineated to be Mn oxy-hydroxide reducing, not sufficiently lowered for As mobilization into groundwater. In contrast, the enrichments of NH4+, PO43-, Fe and As along with lower Eh in groundwater of GSA reflect reductive dis-solution of Fe oxy-hydroxide coupled to microbially mediated oxidation of organic matter as the prevailing redox process causing As mobilization into groundwater of this aquifer type. In some portions of GSA the redox status even has reached to the stage of SO42- reduction, which to some extent might sequester dissolved As from groundwater by co-precipitation with authigenic pyrite. Despite having low concentration of As in groundwater of the BSA the concentration of Mn often exceeds the drinking water guidelines, which warrants rigorous assessment of attendant health risk for Mn prior to considering mass scale exploitation of the BSA for possible sustainable drinking water supply.

  • 115.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Nath, Bibhash
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Kundu, Arnit K.
    Mandal, Ujja
    Mukherjee, Abhijit
    Chatterjee, Debashis
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Testing tubewell platform color as a rapid screening tool for arsenic and manganese in drinking water wells2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, ISSN 0013-936X, Vol. 46, p. 434-440Article in journal (Refereed)
    Abstract [en]

    A low-cost rapid screening tool for arsenic (As) and manganese (Mn) in groundwater is urgently needed to formulate mitigation policies for sustainable drinking water supply. This study attempts to make statistical comparison between tubewell (TW)platform color and the level of As and Mn concentration in groundwater extracted from the respective TW (n = 423), to validate platform color as a screening tool for As andMnin groundwater. The result shows that a black colored platform with 73% certainty indicates that well water is safe fromAs, while with 84% certainty a red colored platform indicates that well water is enriched with As, compared to WHO drinking waterguideline of 10 μg/L. With this guideline the efficiency, sensitivity, and specificity of the tool are 79%, 77%, and 81%, respectively.However, the certainty values become 93% and 38%, respectively, for black and redcolored platforms at 50 μg/L, the drinking water standards for India and Bangladesh. The respective efficiency, sensitivity, and specificity are 65%, 85%, and 59%. Similarly for Mn, black and red colored platform with 78% and 64% certainty, respectively, indicates that wellwater is either enriched or free from Mn at the Indian national drinking water standard of 300 μg/L. With this guideline the efficiency, sensitivity, and specificity of the tool are 71%, 67%, and 76%, respectively. Thus, this study demonstrates that TWplatform color can bepotentially used as an initial screening tool for identifying TWs with elevated dissolved As andMn, tomake further rigorous groundwater testing more intensive and implement mitigation options for safe drinking water supplies.

  • 116.
    Bleppony, Rueben Arnoldz
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Increased Salinity of Drilled Wells in Stockholm County – analysis of natural factors.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Almost 50 % of drinking water in Sweden comes from aquifers. The sustainability of groundwater resources in Stockholm County is threatened by increased salinity although most of the drinking water comes from Lake Mälaren. For a region known to be located within the areas covered by seawater after the last glaciation, the health and socio-economic development of the county is in a balance as development plans are challenged by high risk of salt groundwater. It is therefore important to know the extent and spread of salinity within the areas and the factors that correlate well with the salinity in the first attempt to study the risk of the areas to high salt content of groundwater. This paper looks at the distribution of salinity within the county and analyses the correlation between salinity and several natural factors. Using well co-ordinates and chemical data (compiled by Stockholm County Administration), and digital topographical, geological and land use data (from SGU and Swedish Land Survey), it is possible to project and visualize wells and salinity over the area, spatially develop and extract natural factor values to respective wells based on their co-ordinates, and finally perform statistical analyses on a resultant well attributes table, with the aid of Surfer, ArcGIS and Statistica Software. Results showing the spatial distribution of wells’ salinity and graphs of variance between the salinity of wells and respective natural factors of topography, depth, predominant soil cover, land use and distance from the sea, are further discussed.

  • 117.
    Blix, Annika
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Enhancing the capacity of seeds as turbidity removal agents in water treatment.: A Minor Field Study.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this master’s thesis was to investigate if defattening of Parkinsonia aculeata (in

    swahili “mkeketa”) and Vigna unguiculata (in swahili “choroko”) would enhance the capacity of the seed’s properties in removing suspended particles from surface water. The seeds are used in local traditional treatment of drinking water in Tanzania. The aim was also to investigate the possibility to reduce high concentrations of fluoride with the seeds. The seeds contain proteins that act as coagulants. Coagulated particulate matter can be flocculated and separated from the water. A purification of the coagulants by defattening was expected to enhance the coagulating capacity. Experiments were conducted in jar-tests with dosages of coagulant solutions of undefattening and defattened seed solutions and alum (aluminium sulphate). The experiments showed that both Parkinsonia aculeata and Vigna unguiculata seeds can compete with alum in drinking water treatment of surface water, reaching the same or better final results in turbidity removal. Both seeds also produce less sludge volumes than alum and functions in turbidity removal together with alum. The seeds may be used as coagulant aids to reduce the usage of chemicals and sludge production. They were not able to clarify turbid waste water and did not reduce high concentrations of fluoride in groundwater. Further, the turbidity-removal capacity of the coagulants had reduced capacities in water with low pH-values.

  • 118. Blomqvist, Göran
    et al.
    Norrström, Ann-Catrine
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Johansson Thunqvist, Eva-Lotta
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Miljöproblem vid drift och underhåll av vägar2001Report (Other academic)
  • 119. Blomqvist, Göran
    et al.
    Riehm, Mats
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Physics.
    ROAD SURFACE WETNESS AS AFFECTED BY EVAPORATION, SURFACE RUNOFF AND TRAFFIC SPLASHINGManuscript (preprint) (Other academic)
    Abstract [en]

    Road surface wetness governs the fate of pollutants on the road surface. The wetness is also important for estimating the risk of ice formation during winters. The road surface water is affected by evaporation, run-off and traffic induced splash and spray. Increased knowledge of how these processes govern the road surface water and how they could be modelled would help to improve the possibility to abate problems with raised levels of air pollutants, as well as traffic safety issues by facilitating optimization of the use of anti- and de-icing chemicals. The aim of this study was to use a modeling tool in order to differentiate between three processes governing the loss of wetness from the road surface within a cross section of a road during two different climatic scenes (winter and spring). Two new measurement techniques were used for detailed measurements of road surface wetness across a road to validate the model. It could be concluded that the changes in wetness on the road can be simulated from general simple weather and traffic information. Furthermore, the wetness across the road is very heterogeneous and can be described by a distribution of regulating parameter values. The presented model application has a potential for real time application on roads and within a region and also for predictions of future conditions by using weather forecast data.

  • 120. Blomqvist, P
    et al.
    Jansson, Per-Erik
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Espeby, Bengt
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Brunberg, A-C
    Olofsson, Bo
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Norrström, Ann-Catrin
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Litoral produktion och sjöbäckens hydrologi2001Report (Other academic)
  • 121.
    Boberg, Björn
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Holm, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    FEM modeling of concrete gravity dams.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 122.
    Bohlin, Caroline
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Rundqvist, Maria
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Exploatering i Roslagens hjärta – en studie av dagvattenplaneringen vid det framtidaRosenkälla handelsområde.2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 123.
    Borgström, Kristina
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Spridningsrisk för metaller till grundvatten från en vägslänt2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is well known that the areas in the vicinity of roads are polluted due to traffic, mainly in form of heavy metals and

    PAHs (polycyclic aromatic hydrocarbons). The pollutions are transported to the surroundings by air, splash or

    highway runoff where they either infiltrate into the ground or flow on the surface to a surface water recipient. The

    Swedish National Road Administration has the responsibility for the national road networks impact on the environment.

    The water protection area of Östra Mälaren contains 230 kilometres governmental roads of which some are

    the most busy ones in Sweden (E4, E18 and E20). Due to this a cost effective way is needed to take care of the

    polluted highway runoff that may contaminate the water recipients in the surroundings. Soils have capabilities to

    retain pollutions which stop the further transport to the groundwater. This capacity of the soil differs between

    different sites since the soil material is very heterogonous. The soils texture decides to a large degree the concentration

    of the metal in the leachate. A large amount of clay and humic substances gives a high capacity to retain metal

    ions, whereas in a more sandy soil the leaching of pollutions is larger. To examine the risk of downward transport in

    a drain situated along a busy highway outside Stockholm, samples were taken and analyzed for the total content of

    Cd, Cr, Cu, Pb and Zn and the potential leachable amount. The gradients of the total content with depth and distance

    from the road showed that the drain was polluted and most obvious was this for Cu, Pb and Zn. Cadmium had

    the highest concentration in the bottom of the drain while the concentration in the slope (e.g. closer to the highway)

    were significantly lower. The Cr concentration was close to background values and showed no significant trend at all.

    The leaching tests showed that only small amounts of the total metal contents were leachable, 0,16 %, 2 % and 8,8 %

    for Pb, Cu and Zn. In spite of this the concentrations of Pb and Zn exceeded the drinking water criteria. This indicates

    that the groundwater in the area may have enhanced metal concentrations. Cu and Pb occurred in association

    with dissolved organic carbon (DOC). The amount of DOC will increase with increasing pH and accordingly the risk

    of leaching. Zinc showed high correlations with Mn which indicates that Zn is adsorbed to oxides. This will lead to

    that a higher loss of Zn is expected in an environment with low pH and reduced conditions. In this study Lake

    Bornsjön is the final recipient and the inflow to the lake is situated 5 kilometres from the studied drain and hence the

    impact of the polluted highway runoff will be insignificant due to dilution. Although, in other parts in the water

    protection area the situation might be different, as well as in the future and this can lead to a change in the pollution

    load on the water reservoir.

  • 124. Bormann, H.
    et al.
    Holländer, H. M.
    Blume, T.
    Buytaert, W.
    Chirico, G. B.
    Exbrayat, J. -F
    Gustafsson, David
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Hölzel, H.
    Kraft, P.
    Krauße, T.
    Nazemi, A.
    Stamm, C.
    Stoll, S.
    Blöschl, G.
    Flühler, H.
    Comparative discharge prediction from a small artificial catchment without model calibration: Representation of initial hydrological catchment development2011In: Die Bodenkultur, ISSN 0006-5471, Vol. 62, no 1-4, p. 23-29Article in journal (Refereed)
    Abstract [en]

    Ten conceptually different models were applied to predict the discharge from the 6 ha artificial Chicken Creek catchment in Lausatia, North-East Germany, which has been created in an open cast mining area. The study consisted of three steps to make a model intercomparison with the objective of a priori prediction of the water balance and the discharge dynamics. In order to test the ability of each model and modeller to predict water flows in an ungauged catchment, only soil texture, topography, vegetation coverage and climate data were provided to the modellers in the first step. Hydrological data on discharge, soil moisture and groundwater levels were withheld. This enabled us to assess the predictive capabilities of the models under sparse data conditions. The predicted components of the water balance varied in a wide range. None of the model simulations came close to the observed water balance for the entire 3-year study period. Discharge was mainly predicted as subsurface flow with little surface runoff. In reality, surface runoff was a major flow component despite the fairly coarse soil texture. In the second step, additional process knowledge was gained during a joint field visit. The occurence of gully erosion and surface crusting was detected and implemented into the models. Consequently, model predictions changed considerably. The previous simulations dominated by subsurface flow changed to surface flow-dominated simulations. Additional data, provided in the third step, mainly confirmed the parameterisations and assisted in a better definition of initial conditions and subsurface storage. The comparison indicates that, in addition to model philosophy, the personal judgement of the modellers was a major source of the differences in the model results. The model parameterisation and choice of initial conditions depended on the modeller's judgement and were therefore a result of the modellers' experience in terms of model types and case studies.

  • 125. Brenčič, M.
    et al.
    Dawson, A.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Francois, D.
    Leitao, T.
    Pollution mitigation2008In: Water in Road Structures: Movement, Drainage and Effects / [ed] Dawson, A., Springer, 2008, p. 283-297Chapter in book (Refereed)
  • 126.
    Buffay, Robert
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Determination of site-specific guidelines for contaminated soil by a Norwegian model2001Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 127. Bulbul, A.
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Huq, S.M.I.
    Gunaratna, K.R.
    Arsenic uptake by fresh water green alga, Chlamydomonas2008In: Groundwater for Sustainable Development: Problems, Perspectives and Challenges / [ed] Bhattacharya, P., Ramanathan, AL., Mukherjee A.B., Bundschuh, J., Chandrasekharam, D. Keshari, A.K., The Netherlands: Taylor and Francis/A. A. Balkema , 2008, p. 389-396Chapter in book (Refereed)
  • 128.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Bhattacharya, ProsunKTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.Chandrashekharam, D.
    Natural Arsenic in Groundwater: Occurrence, Remediation and Management2005Collection (editor) (Refereed)
  • 129.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Bhattacharya, ProsunKTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.Chandrashekharam, DornadulaIndian Institute of Technology-Bombay, Mumbai-400076, India.
    Natural Arsenic in Groundwater: Occurrences, Remediation and Management: Proceedings of the Pre-Congress Workshop "Natural Arsenic in Groundwater", 32nd International Geological Congress, Florence, Italy, 18-19 August 20042005Conference proceedings (editor) (Refereed)
    Abstract [en]

    Groundwater is an important resource that serves as a backbone of human development. In several regions -mostly in developing countries- groundwater from sedimentary and hard rock aquifers used for drinking are naturally contaminated with arsenic. In different countries in Asia such as eastern India, Bangladesh, Cambodia, China, Nepal, Pakistan, Taiwan, Thailand and Vietnam, the situation of arsenic toxicity is alarming and severe health problems are reported amongst the inhabitants relying on groundwater as sources of water for drinking purposes. Arsenic occurrences in groundwater in Bengal Delta Plain of West Bengal, India and Bangladesh is one of the largest environmental health disaster of the present century, where at least 50 million people is at risk of cancer and other arsenic related diseases due to the consumption of high arsenic groundwater. In these same countries, land and agricultural sustainability is threatened by the use of arsenic contaminated irrigation water. In several Middle- and South-American countries, for example in Argentina, Brazil, Chile and Mexico, high arsenic is reported in natural waters. In Argentina, at least 1.2 million people are affected. Elevated levels of natural arsenic in groundwater due to geogenic sources, is therefore an issue of primary environmental concern, which limits the use of these resources for drinking or other purposes, and hinders the economic and social development. Hence there is need to improve our understanding on the genesis of high arsenic groundwaters from the various aquifers in order to develop strategies of e to improve the socio-economic status of the affected regions.

  • 130. Bundschuh, Jochen
    et al.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Hoinkis, Jan
    Kabay, Nalan
    Jean, Jiin-Shuh
    Litter, Marta I.
    Groundwater arsenic: From genesis to sustainable remediation2010In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 44, no 19, p. 5511-5511Article in journal (Other academic)
  • 131.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Sracek, Ondra
    Fernanda Mellano, M.
    Ramirez, Antonio E.
    Storniolo, Angel del R.
    Martin, Raul A.
    Cortes, Julia
    Litter, Marta I.
    Jean, Jiin-Shuh
    Arsenic removal from groundwater of the Chaco-Pampean Plain (Argentina) using natural geological materials as adsorbents2011In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 46, no 11, p. 1297-1310Article in journal (Refereed)
    Abstract [en]

    Use of natural geological materials for arsenic (As) removal is an emerging solution at a household level for poor people in remote rural settlements, especially when the materials are locally available and can be collected by the local population. Their low or zero cost makes these materials very attractive compared with synthetic or commercial materials. Sometimes, this may be the only option to provide safe water to very poor settlements. Their suitability for As removal from water is mainly due to adsorption, co-precipitation and ion exchange processes involving Fe- and Al-rich minerals and clay minerals present in the soils or sediments. In the present study, various clay-rich soils from the Santiago del Estero province (SDE, NW Argentina) and, for comparison, a laterite from the Misiones province have been tested as adsorbents for As in shallow naturally contaminated groundwaters of the Rio Dulce alluvial aquifer in SDE. Batch adsorption experiments showed higher As(V) removal for the Misiones laterite sample (99 %) as compared with the soils from SDE (40-53 %), which can be related to lower contents of water-soluble and oxalate extractable Al and Fe in the last samples. These results suggest the application of the Misiones laterite soil as an alternative for As removal. However, high transportation costs from Misiones to SDE can be an economical restriction for the low-income population of SDE.

  • 132.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Jakariya, Md
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Geochemistry and Ecotechnology.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Litter, M.I.
    Garcia, M.E.
    Arsenic-safe aquifers as a socially acceptable source of safe drinking water: What can rural Latin America learn from Bangladesh experiences?2009In: Natural Arsenic in Groundwater of Latin America: Occurrence, health impact and remediation, The Netherlands: CRC Press/Balkema , 2009, p. 677-685Chapter in book (Refereed)
  • 133.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630). Karlsruhe University of Applied Sciences, Karlsruhe, Germany .
    Litter, M. I.
    Nicolli, H. B.
    Hoinkis, J.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Identifying occurrences of groundwater arsenic in Latin America: A continent-wide problem and challenge2010In: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, p. 512-516Conference paper (Refereed)
  • 134.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Litter, Marta
    Ciminelli, Virginia S. T.
    Eugenia Morgada, Maria
    Cornejo, Lorena
    Hoyos, Sofia Garrido
    Hoinkis, Jan
    Teresa Alarcon-Herrera, Ma
    Aurora Armienta, Maria
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Emerging mitigation needs and sustainable options for solving the arsenic problems of rural and isolated urban areas in Latin America: A critical analysis2010In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 44, no 19, p. 5828-5845Article in journal (Refereed)
    Abstract [en]

    In this work, current information about the contamination of ground- and surface-water resources by arsenic from geogenic sources in Latin America is presented together with possible emerging mitigation solutions. The problem is of the same order of magnitude as other world regions, such as SE Asia, but it is often not described in English. Despite the studies undertaken by numerous local researchers, and the identification of proven treatment methods for the specific water conditions encountered, no technologies have been commercialized due to a current lack of funding and technical assistance. Emerging, low-cost technologies to mitigate the problem of arsenic in drinking water resources that are suitable for rural and urban areas lacking centralized water supplies have been evaluated. The technologies generally use simple and low-cost equipment that can easily be handled and maintained by the local population. Experiences comprise (i) coagulation/filtration with iron and aluminum salts, scaled-down for small community-and household-scale-applications, (ii) adsorption techniques using low-cost arsenic sorbents, such as geological materials (clays, laterites, soils, limestones), natural organic-based sorbents (natural biomass), and synthetic materials. TiO2-heterogeneous photocatalysis and zerovalent iron, especially using nanoscale particles, appear to be promising emergent technologies. Another promising innovative method for rural communities is the use of constructed wetlands using native perennial plants for arsenic rhizofiltration. Smallscale simple reverse osmosis equipment (which can be powered by wind or solar energy) that is suitable for small communities can also be utilized. The individual benefits of the different methods have been evaluated in terms of (i) size of the treatment device, (ii) arsenic concentration and distribution of species, chemical composition and grade of mineralization in the raw water, (iii) guidelines for the remaining As concentration, (iv) economical constrains, (v) complexity of installation and maintenance, and infrastructure constraints (e.g. electricity needs). (c) 2010 Elsevier Ltd. All rights reserved.

  • 135.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Litter, Marta I.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Arsenic in Latin America, an unrevealed continent: Occurrence, health effects and mitigation2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 429, p. 1-1Article in journal (Other academic)
  • 136.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Litter, Marta I.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Targeting arsenic-safe aquifers for drinking water supplies2010In: Environmental Geochemistry and Health, ISSN 0269-4042, E-ISSN 1573-2983, Vol. 32, no 4, p. 307-315Article in journal (Refereed)
    Abstract [en]

    At present, 70 countries worldwide are affected by groundwater contamination by arsenic (As) released from predominantly geogenic sources. Consequently, the As problem is becoming a global issue. The option to target As-safe aquifers, which uses geological, geochemical, hydrogeological, morphological and climatic similarities to delimit As-safe aquifers, appears as a sustainable mitigation option. Two pilot areas, Meghna Flood Plain in Matlab Upazila, representative of Bengal Delta in Bangladesh, and Rio Dulce Alluvial Cone, representing a typical aquifer setting in the Chaco-Pampean Plain in Argentina groundwater As occurrence, were compared. In rural Bangladesh, As removal techniques have been provided to the population, but with low social acceptance. In contrast, "targeting As-safe aquifers" was socially accepted in Bangladesh, where sediment color could be used to identify As-safe aquifer zones and to install safe wells. The investigation in Argentina is more complex because of very different conditions and sources of As. Targeting As-safe aquifers could be a sustainable option for many rural areas and isolated peri-urban areas.

  • 137.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Litter, Marta I.
    Parvez, Faruque
    Roman-Ross, Gabriela
    Nicolli, Hugo B.
    Jean, Jiin-Shuh
    Liu, Chen-Wuing
    Lopez, Dina
    Armienta, Maria A.
    Guilherme, Luiz R. G.
    Gomez Cuevas, Alina
    Cornejo, Lorena
    Cumbal, Luis
    Toujaguez, Regla
    One century of arsenic exposure in Latin America: A review of history and occurrence from 14 countries2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 429, p. 2-35Article, review/survey (Refereed)
    Abstract [en]

    The global impact on public health of elevated arsenic (As) in water supplies is highlighted by an increasing number of countries worldwide reporting high As concentrations in drinking water. In Latin America, the problem of As contamination in water is known in 14 out of 20 countries: Argentina, Bolivia, Brazil, Chile, Colombia, Cuba, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Peru and Uruguay. Considering the 1 0 mu g/L limit for As in drinking water established by international and several national agencies, the number of exposed people is estimated to be about 14 million. Health effects of As exposure were identified for the first time already in the 1910s in Bellville (Cordoba province, Argentina). Nevertheless, contamination of As in waters has been detected in 10 Latin American countries only within the last 10 to 15 years. Arsenic is mobilized predominantly from young volcanic rocks and their weathering products. In alluvial aquifers, which are water sources frequently used for water supply, desorption of As from metal oxyhydroxides at high pH (>8) is the predominant mobility control; redox conditions are moderate reducing to oxidizing and As(V) is the predominant species. In the Andes, the Middle American cordillera and the Transmexican Volcanic Belt, oxidation of sulfide minerals is the primary As mobilization process. Rivers that originate in the Andean mountains, transport As to more densely populated areas in the lowlands (e.g. Rimac river in Peru, Pilcomayo river in Bolivia/Argentina/Paraguay). In many parts of Latin America, As often occurs together with F and B; in the Chaco-Pampean plain As is found additionally with V. Mo and U whereas in areas with sulfide ore deposits As often occurs together with heavy metals. These co-occurrences and the anthropogenic activities in mining areas that enhance the mobilization of As and other pollutants make more dramatic the environmental problem.

  • 138.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Nath, Bibhash
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Liu, Chen-Wuing
    Aurora Armienta, Maria
    Moreno Lopez, Myriam V.
    Lopez, Dina L.
    Jean, Jiin-Shuh
    Cornejo, Lorena
    Lauer Macedo, Luciene Fagundes
    Tenuta Filho, Alfredo
    Arsenic in the human food chain: the Latin American perspective2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 429, p. 92-106Article, review/survey (Refereed)
    Abstract [en]

    Many regions of Latin America are widely reported for the occurrence of high arsenic (As) in groundwater and surface water due to a combination of geological processes and/or anthropogenic activities. In this paper, we review the available literature (both in English and Spanish languages) to delineate human As exposure pathways through the food chain. Numerous studies show that As accumulations in edible plants and crops are mainly associated with the presence of high As in soils and irrigation waters. However, factors such as As speciation, type and composition of soil, and plant species have a major control on the amount of As uptake. Areas of high As concentrations in surface water and groundwater show high As accumulations in plants, fish/shellfish, livestock meat, milk and cheese. Such elevated As concentrations in food may result in widespread health risks to local inhabitants, including health of indigenous populations and residents living close to mining industries. Some studies show that As can be transferred from the water to prepared meals, thereby magnifying the As content in the human diet. Arsenic speciation might also change during food preparation, especially during high temperature cooking, such as grilling and frying. Finally, the review of the available literature demonstrates the necessity of more rigorous studies in evaluating pathways of As exposure through the human food chain in Latin America.

  • 139.
    Byman, Lina
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Treatment of wash water from road tunnels.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Tunnels have become increasingly important in the development of road networks to meet rising transportation demands. Washing of road tunnels must be performed regularly to ensure traffic safety. The washing procedure generates significant amount of polluted wash water. Before discharge to a receiving water body, treatment is necessary to avoid potential degradation of the water quality. In this study, 12 in situ sedimentation experiments were conducted to evaluate treatment efficiency of sedimentation, with and without the addition of chemical flocculent. The findings showed that untreated tunnel wash water was highly polluted with total suspended solids (804-9690 mg/l), PAHs (0.4–29 μg/l) and heavy metals. Most pollutants were associated with the particulate material. Significant correlations (r2 > 0.95) were found between suspended solids and metals. Efficient removal of pollutants was possible by sedimentation with addition of flocculent. Within 20 hours of sedimentation low concentrations were reached of suspended solids (<15mg/l), PAHs (<0.1 μg/l), Cd (<0.05 μg/l), Cr (< 8 μg/l), Hg (<0.02 μg/l), Pb (<0.5 μg/l) and Zn (< 60 μg/l). The results confirm the possibility to treat tunnel wash water with sedimentation and flocculation and to discharge treated wash water to a recipient, provided particular attention is given to very sensitive water bodies.

  • 140. Bäckstrom, M.
    et al.
    Karlsson, S.
    Bäckman, L.
    Folkeson, Lennart
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Lind, B.
    Mobilisation of heavy metals by deicing salts in a roadside environment2004In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 38, no 3, p. 720-732Article in journal (Refereed)
    Abstract [en]

    The seasonal variations of some selected heavy metals (Cd, Cu, Pb and Zn) and principal anions in soil solutions were monitored as a function of distance from the road at two field sites in Sweden. During the winter, the conductivity, concentrations of dissolved sodium and chloride increased dramatically due to the application of deicing agents (i.e. NaCl). Due to ion exchange, the pH decreased one unit in the soil solutions, whereas the concentrations of total organic carbon decreased due to coagulation and/or sorption to stationary solids. The heavy metal concentrations increased during the winter, but through different mechanisms. Cadmium concentrations in the aqueous phase increased as a response to ion exchange, possibly also enhanced by the formation of chloride complexes. Similarly, the concentrations of zinc increased, due to ion exchange, with calcium and protons. The mechanisms of mobilisation for copper and lead were not that clear probably due to association with coagulated or sorbed organic matter in combination with colloid dispersion.

  • 141. Bäckström, A.
    et al.
    Antikainen, Janne
    Backers, Tobias
    Feng, X.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Kobayashi, A.
    Koyama, Tomofumi
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Pan, P.
    Rinne, M.
    Shen, B.
    Hudson, J.A.
    Numerical modelling of unaxial compressive failure of granite with and without saline porewater2008In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 45, no 7, p. 1126-1142Article in journal (Refereed)
  • 142.
    Bäckström, Ann
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    A study of impact fracturing and electric resistivity related to the Lockne impact structure, Sweden2005In: Impact Tectonics / [ed] Koeberl C; Henkel H, 2005, p. 389-404Conference paper (Refereed)
    Abstract [en]

    The fracture frequency and the electric resistivity of outcrops of crystalline basement rocks at the Lockne meteorite impact site have been studied in order to investigate the extent and radial changes of impact induced fracturing. By measuring the electric resistivity and the fracture frequency at the same outcrops, the effect of fracturing on the electric properties of the rock is estimated and correlated with the fracture frequency. A negative linear correlation between the Log of fracture frequency and the Log of electric resistivity was found.

    It was also found that the fracture frequency decreases in a transition zone over a distance of about 1100 m across the southern margin of the impact structure. A similar set of measurements was made across the suggested northern limit of the structure, but no change was detected. This implies that the outer limit of the Tandsbyn Breccia is further to the north. The studied area is, therefore, not likely to be the. margin of the structure.

  • 143.
    Bäckström, Ann
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Rock damage caused by underground excavation and meteorite impacts2008Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The intent of this thesis is to contribute to the understanding of the origin of fractures in rock. The man-made fracturing from engineering activities in crystalline rock as well as the fracturing induced by the natural process of meteorite impacts is studied by means of various characterization methods. In contrast to engineering induced rock fracturing, where the goal usually is to minimize rock damage, meteorite impacts cause abundant fracturing in the surrounding bedrock. In a rock mass the interactions of fractures on the microscopic scale (mm-cm scale) influence fractures on the mesoscopic scale (dm-m scale) as well as the interaction of the mesocopic fractures influencing fractures on the macroscopic scale (m-km scale). Thus, among several methods used on different scales, two characterization tools have been developed further. This investigation ranges from the investigation of micro-fracturing in ultra-brittle rock on laboratory scale to the remote sensing of fractures in large scale structures, such as meteorite impacts. On the microscopic scale, the role of fractures pre-existing to the laboratory testing is observed to affect the development of new fractures. On the mesoscopic scale, the evaluation of the geometric information from 3D-laser scanning has been further developed for the characterisation of fractures from tunnelling and to evaluate the efficiency of the tunnel blasting technique in crystalline rock. By combining information on: i) the overbreak and underbreak; ii) the orientation and visibility of blasting drillholes and; iii) the natural and blasting fractures in three dimensions; a analysis of the rock mass can be made. This analysis of the rock mass is much deeper than usually obtained in rock engineering for site characterization in relation to the blasting technique can be obtained based on the new data acquisition. Finally, the estimation of fracturing in and around two meteorite impact structures has been used to reach a deeper understanding of the relation between fracture, their water content and the electric properties of the rock mass. A correlation between electric resistivity and fracture frequency in highly fractured crystalline rock has been developed and applied to potential impact crater structures. The results presented in this thesis enables more accurate modelling of rock fractures, both supporting rock engineering design and interpretation of meteorite impact phenomena.

  • 144.
    Bäckström, Ann
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Cosgrove, John W.
    Department of Earth Science and Engineering, Imperial College, London.
    Hudson, John A.
    Department of Earth Science and Engineering, Imperial College, London.
    Interpretation of the development of induced cracks within a pre-cracked rock microstructure and the similarities with the geometry of larger-scale geological fracturesIn: Journal of Structural Geology, ISSN 0191-8141, E-ISSN 1873-1201Article in journal (Other academic)
  • 145.
    Bäckström, Ann
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Feng, Quanhong
    Berg Bygg Konsult AB.
    Lanaro, Flavio
    Berg Bygg Konsult AB.
    Excavation Damage Zone (EDZ) at the TASQ tunnel (Äspö, Sweden): Quantification of blasting effects on the geological settings by 3D-laser-scanningIn: Engineering Geology, ISSN 0013-7952, E-ISSN 1872-6917Article in journal (Other academic)
  • 146.
    Bäckström, Ann
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Feng, Quanhong
    Berg Bygg Konsult AB.
    Lanaro, Flavio
    Berg Bygg Konsult AB.
    Christiansson, Rolf
    Swedish Nuclear Fuel and Waste Management Co.
    Evaluation of the Excavation Damage Zone (EDZ) by using 3-D laser scanning technique2006In: The 4th Asian Rock Mechanics Symposium, Singapore, 8 - 10 November 2006, 2006Conference paper (Other academic)
  • 147.
    Bäckström, Ann
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    Koyama, Tomofumi
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Engineering Geology and Geophysics.
    et al.,
    Numerical modelling of uniaxial compressive failure of granite with and without saline porewater2008In: International Journal of Rock Mechanics And Mining Sciences, ISSN 1365-1609, E-ISSN 1873-4545, Vol. 45, no 7, p. 1126-1142Article in journal (Refereed)
    Abstract [en]

    It is important for rock engineering design to be able to validate numerical simulations, i.e. to check that they adequately represent the rock reality. In this paper, the capability and validity of four numerical models is assessed through the simulation of an apparently simple case: the complete process of microstructural breakdown during the uniaxial compressive failure of intact crystalline rock. In addition to comparing the capabilities of the four models, the results generated by each model were compared with the experimentally determined complete stress-strain curves for the Swedish Avro granite for different porewater conditions. In this way, it has been possible to audit the models' adequacy for this particular simulation task. It was found that although the models had common features, they were each idiosyncratically different and required considerable expertise to match the actual stress-strain curves (which did not monotonically increase in axial strain)-indicating that, for more complex simulations, both adequate modelling and appropriate validation are not going to be an easy task. The work was conducted within the framework of the international 2004-2007 DEmonstration of COupled models and their VALidation against EXperiments with emphasis on Thermo Hydro Mechanic and Chemical aspects (DECOVALEX-THMC) phase on coupled modelling extended to include chemical effects and with application to the excavation damaged zone (EDZ) in crystalline rock.

  • 148.
    Caglia, Stefania
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Nitrogen Removal in the Pilot Plant ITEST (Increased Technology in Sewage Treatment).2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Regions with a cold winter, as in the Baltic countries, have a problem to meet the nitrogen requirement in the Urban Wastewater Treatment Directive 98/15/EC. Especially in the winter season, the temperature of the influent wastewater could arrive also below 10°C and this delays the biological processes that takes place in the wastewater treatment. With the decrease of the temperature, the efficiency of nitrogen removal in the system decreases and leads to a high nitrogen loading in the effluent.

    The ITEST (Increased Technology and Efficiency in Sewage Treatment) project situated in Hammarby Sjöstadsverk in Stockholm has as its main aim to enhance nitrogen removal, thereby increasing the temperature in the incoming wastewater. The pilot plant ITEST is comprised of two treatment lines, one works with natural temperature influent and the other works at the temperature of 20 °C. In order to warm the incoming water a heating system, using waste heat, is used, leading to save energy.

    The two test lines were compared analyzing different parameters from January to May 2013. Total nitrogen, nitrate-nitrogen and ammonium-nitrogen concentrations were measured in the incoming water and in the effluent from the two treatment lines. Hence, the efficiency of the nitrogen removal was compared between the reference and the temperature line.

    In the period where the system was well functioning, the results show a nitrogen efficiency with a maximum of 92 % of removal of total nitrogen for the temperature line compared to only 65 % for the reference line. In the period where the system did not have any troubles the total nitrogen is under 10 mg/l, which is the limit of total nitrogen discharges specified in the Directive. Instead, for the sludge volume and the suspended solids any particular difference can be noticed from the two lines of treatment. In conclusion, in the temperature line can be noticed a great efficiency in nitrogen removal compared to the reference line.

  • 149.
    Carstens, Christoffer
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering.
    Hydrodynamic capacity study of the wave-energized Baltic aeration pump: General applicability to the Baltic Sea and location study for a pilot project in Kanholmsfjärden2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To counteract one of the most urgent environmental issues in the Baltic Sea; eutrophication, excessivealgal blooms and hypoxia, a proposal to use wave energy to pump oxygen-rich surface water towardsthe sea bottom is investigated. Proposals have suggested that 100 kg of oxygen per second is needed tooxygenate bottom water and enhance binding of phosphorus to bottom sediments. This corresponds to 10 000 m3/s of oxygen-rich surface water. This thesis investigates a wave-powered device to facilitatethis oxygen ux. Results give expected water flow rates between 0.15 - 0.40 m3/s and meter breakwater.The mean specic wave power for the analyzed wave data is calculated to be between 3 - 4 kW/m wavecrest and the median to 1 kW/m. This study indicate, however, that the energy uxes in the BalticProper are signicantly higher. The study gives that the wave climate of the Baltic Sea is suffciently intense to facilitate vertical pumping with a feasible number of breakwaters. A full-scale implementationin the Baltic Sea would require some 300 to 1 200 oating breakwaters of a length of 50 m each. Thetotal cost is roughly estimated to 170 - 680 million EURO. The study also concludes that the interleavingof surface water should be constrained to a relatively small vertical distance from the outlet depth(20 - 30 m) and not stir up deep water to the surface. Wave modelling for the proposed pilot locationKanholmsfjärden indicate that this bay is not large enough to permanently produce a favorable waveclimate. It is, however, still an interesting location consistently to its vicinity to Stockholm and relativelylong measurement series.

  • 150.
    Carstens, Christoffer
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Water Resources Engineering.
    In the Pipe or End of Pipe?: Transport and Dispersion of Water-borne Pollutants and Feasibility of Abatement Measures2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Eutrophication is one of the key environmental problems of today, both in terms of complexity and magnitude. For the Baltic Sea (BS), eutrophication is an acute problem, leading to hypoxic conditions at the bottom; a situation that is sustained and amplified, when phosphorus is released from hypoxic sediments. Reducing nutrient loading is a top political priority but the present situation is believed to require active measures within the catchments and recipients to reduce both loading and adverse effects. Implementation of effective and cost-efficient abatement methods requires understanding of natural processes in watersheds, streams and recipients as well as technological expertise in order to compare the effects of measures of different kinds and locations. This thesis tries to combine process understanding of catchment transport behaviour, especially in coastal zones, and feasibility of certain technologies for reducing nutrient loading and effects of eutrophication in-situ. The over-arching theme is the fate of the individual contaminant, from injection to removal. Transport and dispersion in catchments are investigated, combining physically-based, distributed, numerical groundwater models with Lagrangian stochastic advective reactive solute (LaSAR) transport modelling. The approach is powerful in the sense that it incorporates catchment structural, geomorphological dispersion in the numerical model with hydrodynamic and sub-scale dispersion as well as uncertainty in the LaSAR framework. The study exemplifies the complex nature of transport time distributions in catchments in general and when varying source size and location, importance of dispersion parameters and retention due to molecular diffusion. It is shown that geomorphological control on dispersion is present even for relatively heterogeneous systems and that neither the mean residence time nor a statistical distribution may provide accurate representations of hydrological systems. To combat internal loading of P from sediments in-situ, large-scale aeration of deep waters, halocline ventilation, has been suggested. This study further investigates the feasibility of wave-powered devices to meet the energy demands for such an operation. It is shown that the required amount of oxygen needed to keep the sediments at oxic conditions could be provided, cheaply and efficiently, through the use of wave power.

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