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    Obtaining the effect of sewage network on groundwater quality using MT3DMS code: Case study on Bojnourd plain

    , Article Groundwater for Sustainable Development ; Volume 11 , October , 2020 Kheirandish, M ; Rahimi, H ; Kamaliardakani, M ; Salim, R ; Sharif University of Technology
    Elsevier B. V  2020
    Groundwater contamination is a significant problem related strongly to both the protection of the environment and the need for water. In the present study, groundwater quality was investigated in the Bojnourd watershed. The Bojnourd watershed is located in the northeast of Iran, which covers 65.5 km2 of the North Khorasan province area. There are 11 extracting wells in the region. Annual water extraction from the alluvial aquifer in the area is used for agriculture, drinking, sanitary and industrial consumptions. In this research, groundwater quantity modeling, including calibration and verification by GMS software, had been performed. In the quality modeling stage, pollution contours for... 

    Spatially distributed influence of agro-environmental factors governing nitrate fate and transport in an irrigated stream-aquifer system

    , Article Hydrology and Earth System Sciences ; Volume 19, Issue 12 , 2015 , Pages 4859-4876 ; 10275606 (ISSN) Bailey, R. T ; Ahmadi, M ; Gates, T. K ; Arabi, M ; Sharif University of Technology
    Copernicus GmbH  2015
    Elevated levels of nitrate (NO3) in groundwater systems pose a serious risk to human populations and natural ecosystems. As part of an effort to remediate NO3 contamination in irrigated stream-aquifer systems, this study elucidates agricultural and environmental parameters and processes that govern NO3 fate and transport at the regional (500 km2), local (50 km2), and field scales (<1 km2). Specifically, the revised Morris sensitivity analysis method was applied to a finite-difference nitrogen cycling and reactive transport model of a regional-scale study site in the lower Arkansas River valley in southeastern Colorado. The method was used to rank the influence of anthropogenic activities and... 

    Groundwater travel time computation for two-layer islands

    , Article Hydrogeology Journal ; Volume 24, Issue 4 , 2016 , Pages 1045-1055 ; 14312174 (ISSN) Ketabchi, H ; Mahmoodzadeh, D ; Ataie Ashtiani, B ; Sharif University of Technology
    Springer Verlag  2016
    A closed-form analytical computation of groundwater travel time (GWTT) for two-layer oceanic small island aquifers is developed assuming steady-state and sharp-interface conditions. The two-layer geology impacts on the GWTT are investigated using the developed analytical solution to achieve a greater transparency of such conceptualizations. The results demonstrate that the inclusion of geologic layering leads to large changes in the GWTT. Sensitivity analyses, using specified dimensionless parameters, are employed to assess the influences of hydraulic conductivity, recharge rate, upper layer thickness, and seawater/freshwater density difference parameters, which influence the GWTT. These... 

    Efficient fuzzy Bayesian inference algorithms for incorporating expert knowledge in parameter estimation

    , Article Journal of Hydrology ; Volume 536 , 2016 , Pages 255-272 ; 00221694 (ISSN) Rajabi, M. M ; Ataie Ashtiani, B ; Sharif University of Technology
    Bayesian inference has traditionally been conceived as the proper framework for the formal incorporation of expert knowledge in parameter estimation of groundwater models. However, conventional Bayesian inference is incapable of taking into account the imprecision essentially embedded in expert provided information. In order to solve this problem, a number of extensions to conventional Bayesian inference have been introduced in recent years. One of these extensions is 'fuzzy Bayesian inference' which is the result of integrating fuzzy techniques into Bayesian statistics. Fuzzy Bayesian inference has a number of desirable features which makes it an attractive approach for incorporating expert... 

    Review: Coastal groundwater optimization—advances, challenges, and practical solutions

    , Article Hydrogeology Journal ; Volume 23, Issue 6 , September , 2015 , Pages 1129-1154 ; 14312174 (ISSN) Ketabchi, H ; Ataie Ashtiani, B ; Sharif University of Technology
    Springer Verlag  2015
    Decision models are essential tools for coastal groundwater management (CGM). A combined simulation-optimization framework is employed to develop these models. One of the main barriers in the widespread application of these models for real-world cases is their large computational burden. Recent advances in efficient computational approaches and robust optimization methods can crack this barrier. This study surveys the scientific basis of CGM to provide an overview on this subject and reviews the-state-of-the-art to clarify recent developments and to outline ideas for improving the computational performance. Key details are presented on the performance and choice of possible robust tools such... 

    Vulnerability assessment of urban groundwater resources to nitrate: the case study of Mashhad, Iran

    , Article Environmental Earth Sciences ; Volume 76, Issue 1 , 2017 ; 18666280 (ISSN) Asadi, P ; Ataie Ashtiani, B ; Beheshti, A ; Sharif University of Technology
    Springer Verlag  2017
    Groundwater vulnerability assessment of urban areas is a challenging task in the fast trend of urbanization around the globe. This study introduces a new approach for modifying well-known parameters of common vulnerability indexes to adjust them for urban areas. The approach is independent of a specific weighting system. The aquifer of Mashhad city, contaminated by domestic wastewater, is selected as a case in this study. In order to evaluate the aquifer vulnerability due to anthropogenic activities, at first, parameters of depth to groundwater, recharge, land use, and soil are modified based on their basic concepts and their influences on contamination attenuation. Then, the modified... 

    Planning for groundwater sustainable use: A case study in Nishapur Plain, Iran

    , Article Agricultural Water Management ; Volume 229 , 2020 Abrishamchi, A ; Khakbazan Fard, F ; Taghavi, A ; Sharif University of Technology
    Elsevier B.V  2020
    In Iran, due to arid and semi-arid climate, groundwater resources play an essential role in food production, as well as domestic and industrial water supply. In recent years, increasing population, scarcity of surface water resources, and effects of worldwide and regional climate change have resulted in over-exploitation and unsustainability of these resources in the country. The present study aims to estimate groundwater sustainable yield, examine effects of spatial and temporal scale, and propose a plan for groundwater sustainable use in Nishapur Plain, in the north-east of Iran. In investigating the effects of spatial scale, the area of the plain is divided into several zones, with... 

    Assessment of the impacts of sewerage network on groundwater quantity and nitrate contamination: case study of tehran

    , Article World Environmental and Water Resources Congress 2020: Groundwater, Sustainability, Hydro-Climate/Climate Change, and Environmental Engineering, 17 May 2020 through 21 May 2020 ; 2020 , Pages 53-66 Khorasani, H ; Kerachian, R ; Aghayi, M. M ; Zahraie, B ; Zhu, Z ; Sharif University of Technology
    American Society of Civil Engineers (ASCE)  2020
    Many communities in arid and semi-Arid areas rely on groundwater for drinking water. However, anthropogenic activities such as the use of fertilizers and human waste disposal impose the risk of nitrate pollution to the aquifers. With over 8.5 million population, Tehran, the capital of Iran, has experienced rapid population growth during the past decades while the majority of the city did not have a sewerage network and the main way of wastewater disposal was individual cesspits inside houses. The long-Term discharge of raw wastewater in cesspits has increased nitrate concentration in the Tehran aquifer which serves as a source of one-Third of drinking water for the city. Although the... 

    The millennium-old hydrogeology textbook the Extraction of Hidden Waters by the Persian mathematician and engineer Abubakr Mohammad Karaji (953 CE-1029 CE)

    , Article Hydrology and Earth System Sciences ; Volume 24, Issue 2 , 2020 , Pages 761-769 Ataie Ashtiani, B ; Simmons, C. T ; Sharif University of Technology
    Copernicus GmbH  2020
    We revisit and shed light on the millennium-old hydrogeology textbook The Extraction of Hidden Waters by the Persian mathematician and engineer Karaji. Despite the nature of the understanding and conceptualization of the world by the people of that time, ground-breaking ideas and descriptions of hydrological and hydrogeological perceptions such as components of hydrological cycle, groundwater quality and even driving factors for groundwater flow were presented in the book. Although some of these ideas may have been presented elsewhere, to the best of our knowledge, this is the first time that a whole book was focused on different aspects of hydrology and hydrogeology. More importantly, we... 

    Groundwater governance and implementing the conservation policy: the case study of Rafsanjan Plain in Iran

    , Article Environment, Development and Sustainability ; Volume 22, Issue 8 , October , 2020 , Pages 8183-8210 Mirnezami, S. J ; de Boer, C ; Bagheri, A ; Sharif University of Technology
    Springer Science and Business Media B. V  2020
    The groundwater system in the Rafsanjan aquifer perpetuated sustainably for decades before 1950s; however, its groundwater resources have been overexploited in the recent decades. In this paper, we aim to investigate the water governance system to understand the reasons behind the ongoing overexploitation. Sustainability processes are considered a policy implementation problematic. As such, we employ the contextual interaction theory as a policy implementation framework to assess the groundwater governance as part of the context for the conservation policy. Data for this qualitative research were gathered from legal texts, articles, technical reports, and multiple interviews with authorities... 

    A Study of Practical Methods for Petroleum Hydrocarbons Removal from Polluted Groundwaters in a Refinery

    , M.Sc. Thesis Sharif University of Technology Safdari, Mohammad Saeed (Author) ; Kariminia, Hamid Reza (Supervisor)
    Petroleum based products are the major sources of energy for industry and daily life, With the development of social economy, the demands of the oil have increased dramatically. Petroleum hydrocarbons can cause environmental pollution during various stages of production, transportation, refining and use. Releases of petroleum products(e.g., gasoline, diesel, fuel oil) from aboveground and underground storage tanks or transport pipelines are the major causes of the environment pollution.The major constituents of petroleum hydrocarbons are biodegradable. Many soil microorganisms transform oil hydrocarbons into nontoxic compounds or mineralize them to inorganic compounds. In situ... 

    Fuzzy vulnerability mapping of urban groundwater systems to nitrate contamination

    , Article Environmental Modelling and Software ; Volume 96 , 2017 , Pages 146-157 ; 13648152 (ISSN) Asadi, P ; Hosseini, S. M ; Ataie Ashtiani, B ; Simmons, C. T ; Sharif University of Technology
    Elsevier Ltd  2017
    The aim of this study is to develop a new fuzzy optimization model to find the optimal factor weights of modified DRASTIC index for groundwater vulnerability mapping an urban aquifer to nitrate contamination. Eight factors including water table depth, recharge, aquifer media, soil media, topography, impact of vadose zone, hydraulic conductivity, and land use are considered and rated. A fuzzy linear regression is formulated between the values of eight factors and corresponding nitrate concentration in groundwater. An optimization model based on real code genetic algorithm with objective of minimizing the sum of the fuzzy spread of the regression coefficients is implemented. Aquifer of Mashhad... 

    Semianalytical solutions for contaminant transport under variable velocity field in a coastal aquifer

    , Article Journal of Hydrology ; Volume 560 , 2018 , Pages 434-450 ; 00221694 (ISSN) Koohbor, B ; Fahs, M ; Ataie Ashtiani, B ; Simmons, C. T ; Younes, A ; Sharif University of Technology
    Elsevier B.V  2018
    Existing closed-form solutions of contaminant transport problems are limited by the mathematically convenient assumption of uniform flow. These solutions cannot be used to investigate contaminant transport in coastal aquifers where seawater intrusion induces a variable velocity field. An adaptation of the Fourier-Galerkin method is introduced to obtain semi-analytical solutions for contaminant transport in a confined coastal aquifer in which the saltwater wedge is in equilibrium with a freshwater discharge flow. Two scenarios dealing with contaminant leakage from the aquifer top surface and contaminant migration from a source at the landward boundary are considered. Robust implementation of... 

    Influence of lakebed sediment deposit on the interaction of hypersaline lake and groundwater: A simplified case of lake Urmia, Iran

    , Article Journal of Hydrology ; Volume 588 , 2020 Sheibani, S ; Ataie Ashtiani, B ; Safaie, A ; Simmons, C. T ; Sharif University of Technology
    Elsevier B.V  2020
    Lake Urmia, which was once the second-largest saline lake in the world, has been shrinking dramatically. Moreover, Lake Urmia has become supersaturated with total salinity averaging more than 350 g/l. Salt precipitation and dissolved materials brought by inflowing rivers have formed a layer of sediment with low hydraulic conductivity on the lakebed. Considering the flat bathymetry of Lake Urmia, we conducted a series of numerical simulation scenarios to study the groundwater flow pattern in the vicinity of the hypersaline Lake Urmia using COMSOL Multiphysics®. In the first step, we performed the simulations in steady-state conditions. Secondly, we simulated the lake level fall in 10 years at... 

    Tidal effects on groundwater dynamics in unconfined aquifers

    , Article Hydrological Processes ; Volume 15, Issue 4 , 2001 , Pages 655-669 ; 08856087 (ISSN) Ataie Ashtiani, B ; Volker, R. E ; Lockington, D. A ; Sharif University of Technology
    The variation of seawater level resulting from tidal fluctuations is usually neglected in regional groundwater flow studies. Although the tidal oscillation is damped near the shoreline, there is a quasi-steady-state rise in the mean water-table position, which may have an influence on regional groundwater flow. In this paper the effects of tidal fluctuations on groundwater hydraulics are investigated using a variably saturated numerical model that includes the effects of a realistic mild beach slope, seepage face and the unsaturated zone. In particular the impact of these factors on the velocity field in the aquifer is assessed. Simulations show that the tidal fluctuation has substantial... 

    Groundwater Modelling with the Use of Remote Sensing Technology to Assess the Impact of Changes in Aquifer Conditions on Surface Flow (Case Study: Miandoab plain-Urmia Basin)

    , M.Sc. Thesis Sharif University of Technology Hamzekhani, Hamed (Author) ; Agha Mohammad Hossein Tajrishi, Massoud (Supervisor)
    Groundwater resources are considered as important resources of fresh water specifically in arid and semi-arid regions like Iran. Urmia Lake (UL) basin is one of these regions where groundwater resources play an important role in supplying water and due to inappropriate water resources management during the last two decades it has faced serious problems, like declination of water level in UL. Groundwater and surface water form an integrated system in the UL basin and have a mutual effect on each other. Hence, any improvement in exploitation of aquifers in that region could benefit UL water demand management. Appropriate water resources management in Miandoab plain which transfer almost 50... 

    Model-data interaction in groundwater studies: Review of methods, applications and future directions

    , Article Journal of Hydrology ; Volume 567 , 2018 , Pages 457-477 ; 00221694 (ISSN) Rajabi, M. M ; Ataie Ashtiani, B ; Simmons, C. T ; Sharif University of Technology
    Elsevier B.V  2018
    We define model-data interaction (MDI) as a two way process between models and data, in which on one hand data can serve the modeling purpose by supporting model discrimination, parameter refinement, uncertainty analysis, etc., and on the other hand models provide a tool for data fusion, interpretation, interpolation, etc. MDI has many applications in the realm of groundwater and has been the topic of extensive research in the groundwater community for the past several decades. This has led to the development of a multitude of increasingly sophisticated methods. The progress of data acquisition technologies and the evolution of models are continuously changing the landscape of groundwater... 

    Measurement of moisture and temperature profiles in different layers of soil

    , Article 3rd International Foundation Congress and Equipment Expo 2018: Case Histories and Lessons Learned, IFCEE 2018, 5 March 2018 through 10 March 2018 ; Volume 2018-March, Issue GSP 298 , 2018 , Pages 266-278 ; 08950563 (ISSN) Fazel Mojtahedi, F ; Ali, K ; Nazari, A ; Rezvani, S ; Khatami, A ; Ahmadi, N ; Deep Foundations Institute; International Association of Foundation Drilling; Pile Driving Contractors Association; The Geo-Institute (G-I) of the American Society of Civil Engineers (ASCE) ; Sharif University of Technology
    American Society of Civil Engineers (ASCE)  2018
    Over past decades, extensive research has been performed on the measurement of land subsidence as a result of compaction of aquifer. This paper describes results from a new field-monitoring system to evaluate changes in matric suction and temperature profiles in soil layers over an extended time period. The monitoring system used in this study consists of inserting dielectric sensors into a 105 m borehole, drilled in a site in Ardabil Plain, The monitoring results from the site were used to calibrate predictions from HYDRUS-1D. The physical and hydraulic properties of the soil materials in different layers were obtained through performing some soil characteristics and filter paper tests... 

    Modeling And Assesment of Contaminants in Soil and Ground Water of South Pars Gas Complex Company

    , M.Sc. Thesis Sharif University of Technology Alikhani, Jamal (Author) ; Shayegan, Jalalodden (Supervisor) ; Kariminia, Hamid Reza (Supervisor)
    Ground water is one of major resources of drinking water in Iran and thus, its quality (in terms of absence of pollutants) is a matter of great importance. The main goal of this research was to investigate the pollution concentration in the Ground water and soil in the fields near South Pars Gas Complex Co. (SPGC). The second goal was to determined the source and measure the distribution of the pollutants (in case of presence) and determine potential risks caused by them. The first step was to perform experimental tests in the two regions. In SPGC region, a number of wells were chosen for sampling according to the direction of Ground water movement. All samples were taken using two EPA... 

    Experimental Analysis and Simulation of Pollution Distribution in Ground Water and Soil

    , M.Sc. Thesis Sharif University of Technology Ziyari, Afshin (Author) ; Shayegan, Jalal (Supervisor)
    Underground water is one of major resources of drinking water in Iran and thus, its quality (in terms of absence of pollutants) is a matter of great importance. The main goal of this research was to investigate the pollution concentration in underground water and soil in two regions: Dasht-e-naz in Sari and the fields near Sarkhoun gas refinery. The second goal was to determine the source and measure the distribution of the pollutants (in case of presence) and determine potential risks caused by them. The first step was to perform experimental tests in the two regions. In Sari's Dasht-e-naz region, a number of wells were chosen for sampling according to the direction of underground water...