Department of Earth Sciences Quaid-I-Azam University, Islamabad
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DEVELOPMENT OF A GIS BASED ALLUVIAL PLAIN CONJUNCTIVE USE CONTAMINANT TRANSPORT MODEL OF PARTS OF D. I. KHAN USING 3D MODELING APPROACH ANWAR QADIR Department of Earth Sciences Quaid-i-Azam University, Islamabad 2013 1 DEVELOPMENT OF A GIS BASED ALLUVIAL PLAIN CONJUNCTIVE USE CONTAMINANT TRANSPORT MODEL OF PARTS OF D. I. KHAN USING 3D MODELING APPROACH ANWAR QADIR Department of Earth Sciences Quaid-i-Azam University, Islamabad 2013 2 DEVELOPMENT OF A GIS BASED ALLUVIAL PLAIN CONJUNCTIVE USE CONTAMINANT TRANSPORT MODEL OF PARTS OF D. I. KHAN USING 3D MODELING APPROACH ANWAR QADIR Submitted for the degree of Doctor of Philosophy at the Quaid-I-Azam University, Islamabad 2011 3 Certificate Certified that Mr Anwar Qadir carried out the work contained in this dissertation under my supervision Dr. Zulfiqar Ahmad Department of Earth Sciences Quaid-I-Azam University Islamabad- Pakistan Dr. M. Gulraiz Akhter Chairman Department of Earth Sciences Quaid-I-Azam University Islamabad- Pakistan 4 Abstract The goal of this study was to develop a groundwater flow model and a contaminant transport model to understand the fate of the Arsenic in the groundwater. Visual MODFLOW 4.0, the Waterloo Hydrogeologic Inc. software was utilized for this study. A three-dimensional, finite- difference, groundwater flow model was used to develop a regional conceptualization of the flow system in the D. I. Khan area. The D. I. Khan sand aquifer system has been divided into three gently sloping geohydrologic units. The 2900 Km 2 study area was divided into 33852 cells with dimensions of 500 m by 500 m comprising of 186 columns and 182 rows and containing three layers. The finite difference block centered grid was used with an average depth of model simulation was set to 100 meters that almost equals to the average depth of existing tube wells (water wells). The model region was bounded by Indus River, Takwarrah Nala and the Sheikh Haider Zaman Nala in the east, northeast and southwest respectively. The area also consists of Gomal Nala, Chashma Right Bank Canal (CRBC) and Paharpur canal. The model was also adorned with the various hydraulic parameters spatial distributions including hydraulic conductivity (K), initial heads, recharge, porosity, specific storage (Ss), specific yield (Sy), top and bottom elevation of aquifers. The model was initially run for 10 years in steady state for the year 1985. In steady state a single time step was used. The model was calibrated with several runs by modifying the hydraulic conductivities and recharge values. The Parameter Estimation and Testing (PEST) has been used to do the calibration with the minimum and maximum ranges of 30 hydraulic conductivities and recharge values. The model was also calibrated in transient state in 1985 using steady state heads as initial conditions and assessing the draw downs. The area has been studied with respect to the various anthropogenic activities and found to be contaminated with high salinity, sulphates and Arsenic. The contaminant transport model MT3D was used with the observed Arsenic (As) concentrations and calibrated in 2010 for steady state and non steady state conditions. Model realizations were further projected up to 2025 to monitor the spreading of Arsenic concentration in the groundwater. The preliminary management scenarios were also discussed to address the issue at hand for safety of the inhabitants in the study area. The study results include estimates of hydraulic and transport properties, direction of regional flow, contaminant transport, its fate, prevention, remediation and a discussion of the i results to gain a more complete understanding of the subsurface flow and contaminant transport system. Perhaps this work will be the first step in learning more about the subsurface flow system of the D. I. Khan aquifer, and provide a useful tool to manage and properly plan future management of the groundwater resources. ii Acknowledgement I want to express my infinite sense of gratitude to almighty Allah who is the master of all universes and who blessed me with the strength, patience and consistency to complete this work. It is a great opportunity to express sincere gratitude and sense of devotion to my supervisor Professor Dr. Zulfiqar Ahmad , Department of Earth Sciences, Quaid-i-Azam University, Islamabad for providing me an opportunity to enhance my skills not only in hydrogeology but various other facets of the earth sciences. This thesis was not possible to finish without his consistent encouragement, sympathetic attitude, critical remarks on the technical aspects and support. Higher Education Commission (HEC), Pakistan is acknowledged for granting indigenous fellowship for the finances incurred on this study. I would also like to record my sincerest thanks to faculty members and staff of Earth Sciences Department for their cooperation during my stay at the department. I would also thank Engr. Tahir Nawaz Qureshi (Chief Engineer, WAPDA) and Dr. A. D. Khan (PCRWR) for providing the data regarding this research. Special acknowledgements are extended to the Water Management Department and Public Health Engineering Department, D. I. Khan for the provision of data. Cordial and humble thanks are extended to my friends and Ph.D fellows whose help is undeniable including Dr. M. Sadiq (NESCOM), Dr. Arshad Ashraf (NARC), Dr. Gulraiz Akhter, Associate Professor, Quaid-I-Azam University, Dr. Azam Tasneem, PINSTECH, Islamabad, Dr. M. Zafar, Associate Professor, Bahria University, Dr. Shaheena Tariq, Associate Professor, COMSATS, Islamabad and Dr. Tahseenullah Khan, Professor, Bahria University, Mr. M. Hanif (SUPARCO), Alwina Farooq, Usman Mustafa, Masood Ali Khan and Hamid Hussain for supporting me during this research work at various stages. I express my sincere gratitude to my wife, parents and family members for their understanding, endless love and moral support during the entire study period. I also express my deepest gratitude for the local and international examiners for highlighting the relevant problems of research. iii TABLE OF CONTENTS 1 INTRODUCTION ................................................................................................................. 1 1.1 AIMS AND OBJECTIVES ......................................................................................................... 3 1.2 PREVIOUS WORK .................................................................................................................. 4 2 STUDY AREA DETAILS .................................................................................................... 5 2.1 LOCATION ............................................................................................................................ 5 2.2 TOPOGRAPHY AND RELIEF ................................................................................................... 6 2.2.1 Mountain Highlands .................................................................................................... 7 2.2.2 Piedmont Plain ............................................................................................................ 7 2.2.3 Flood Plain .................................................................................................................. 7 2.2.4 Aeolian Deposits ......................................................................................................... 7 2.2.5 Gravel Fans ................................................................................................................. 8 2.3 CLIMATE .............................................................................................................................. 8 2.3.1 Precipitation ................................................................................................................ 9 2.3.2 Temperature ................................................................................................................ 9 2.3.3 Potential Evapotranspiration .................................................................................... 10 2.4 TECTONIC FRAME WORK OF THE REGION ............................................................................ 11 2.4.1 Geology of the study area.......................................................................................... 12 2.4.2 Consolidated rocks .................................................................................................... 13 2.4.3 Unconsolidated rocks ................................................................................................ 13 2.4.3.1 Piedmont Deposits............................................................................................. 14 2.4.3.2 Punjab Type Deposits........................................................................................ 14 2.4.3.3 Soils ................................................................................................................... 14 2.5 AGRICULTURE .................................................................................................................... 16 2.6 IRRIGATION ........................................................................................................................ 16 2.7 HYDROLOGY ...................................................................................................................... 17 2.8 HYDROGEOLOGY ................................................................................................................ 18 3 CONCEPTUAL MODEL ..................................................................................................