Abstract
The first documented interpretation of the regional-scale hydrostratigraphy and groundwater flow is presented for a ∼21,000-km2 area of the arsenic-affected districts of West Bengal [Murshidabad, Nadia, North 24 Parganas and South 24 Parganas (including Calcutta)], India. A hydrostratigraphic model demonstrates the presence of a continuous, semi-confined sand aquifer underlain by a thick clay aquitard. The aquifer thickens toward the east and south. In the south, discontinuous clay layers locally divide the near-surface aquifer into several deeper, laterally connected, confined aquifers. Eight 22-layer model scenarios of regional groundwater flow were developed based on the observed topography, seasonal conditions, and inferred hydrostratigraphy. The models suggest the existence of seasonally variable, regional, north–south flow across the basin prior to the onset of extensive pumping in the 1970s. Pumping has severely distorted the flow pattern, inducing high vertical hydraulic gradients across wide cones of depression. Pumping has also increased total recharge (including irrigational return flow), inflow from rivers, and sea water intrusion. Consequently, downward flow of arsenic contaminated shallow groundwater appears to have resulted in contamination of previously safe aquifers by a combination of mechanical mixing and changes in chemical equilibrium.
Résumé
Pour la première fois une interprétation de l’hydrostratigraphie à l’échelle régionale et de l’écoulement des eaux souterraines est présenté sur une zone de ∼21,000-km2 des districts affectés par l’arsenic dans l’Ouest du Bengal en Inde (Murshidabad, Nadia, Parganas Nord 24 et Parganas Sud 24 (incluant Calcutta)). Un modèle hydrostratigraphique démontre la présence d’un aquifère continu et semi-captif recouvrant un aquitard épais argileux. L’épaisseur de l’aquifère augmente vers l’est et le sud. Au sud, des couches discontinues d’argile partagent localement l’aquifère proche de la surface en plusieurs aquifères captifs, plus profonds et connectés latéralement. Huit scénarios de modèle d’écoulement régional à 22 couches ont été développés sur la base de la topographie, des conditions saisonnières et de l’hydrostratigraphie déduite. Les modèles suggèrent l’existence d’un écoulement régional variable selon les saisons, orienté nord-sud à travers le bassin avant l’intensification des pompages dans les années 1970. Le pompage a sévèrement modifié les lignes d’écoulement, induisant des gradients hydrauliques verticaux élevés au droit de larges cônes de rabattement. Le pompage a également augmenté la recharge totale (recharge par irrigation inclue, l’eau d’irrigation provenant des aquifères), l’écoulement par les rivières et l’intrusion d’eau de mer. Par conséquent, l’écoulement descendant des eaux phréatiques contaminées par l’arsenic apparaît comme le résultat de la combinaison de mécanismes de mélange et de changements des équilibres chimiques.
Resumen
Se presenta la primera interpretación documentada de hidroestratigrafía y flujo de agua subterránea a escala regional para un área de ∼21,000-km2 de los distritos afectados con arsénico en Bengala Occidental (Murshidabad, Nadia, Parganas 24 Norte y Parganas 24 Sur -incluyendo Calcuta-, India. El modelo hidroestratigráfico demuestra la presencia de un acuífero de arena continuo semi-confinado que sobreyace un acuitardo grueso de arcilla. El acuífero aumenta su espesor hacia el oriente y el sur. En el sur, las capas discontinuas de arcilla dividen localmente el acuífero cercano a la superficie en varios acuíferos confinados más profundos conectados lateralmente. Se desarrollaron ocho escenarios de modelos con 22 capas de flujo regional de agua subterránea en base a la topografía observada, condiciones estacionales, e hidroestratigrafía inferida. Los modelos sugieren la existencia de flujo regional norte-sur con variación estacional a través de la cuenca antes del inicio de bombeo extensivo durante los 1970s. El bombeo ha distorsionado fuertemente el patrón de flujo induciendo gradientes hidráulicos verticales altos a través de anchos conos de depresión. El bombeo también ha incrementado la recarga total (incluyendo el flujo de retorno por riego), entrada de ríos, e incursión de agua de mar. En consecuencia, el flujo descendente de flujo de agua subterránea somera contaminada con arsénico parece dar por resultado la contaminación de acuíferos previamente seguros mediante una combinación de mezcla mecánica y cambios en equilibrio químico.
Similar content being viewed by others
References
Acharyya SK, Lahiri S, Raymahashay BC, Bhowmik A (2000) Arsenic toxicity of groundwater in parts of the Bengal basin in India and Bangladesh: the role of Quaternary stratigraphy and Holocene sea-level fluctuation. Environ Geol 39(10):1127–1137
AIP/PHED (1991) National drinking water mission submission project on arsenic pollution in groundwater in West Bengal. Final report of Steering Committee, Arsenic Investigation Project (AIP) and Public Health Engineering Directorate (PHED), Government of West Bengal, India 58 pp
AIP/PHED (1995) Perspective plan for arsenic affected districts of West Bengal. Arsenic Investigation Project (AIP) and Public Health Engineering Directorate (PHED), Government of West Bengal, India
Alam M, Alam MM, Curray JR, Chowdhury MLR, Gani MR (2003) An overview of the sedimentary geology of the Bengal basin in relation to the regional tectonic framework and basin-fill history. Sediment Geol 155:179–208
Allison MA (1998) Geologic framework and environmental status of the Ganges-Brahmaputra Delta. J Coast Res 14(3):826–836
Allison MA, Khan SR, Goodbred SL, Kuehl SA (2003) Stratigraphic evolution of the late Holocene Ganges-Brahmaputra lower delta plain. Sediment Geol 155(3–4):317–342
Ashfaque KN, Harvey CF (2006) Groundwater flow dynamics and arsenic mobilization in Mushiganj, Bangladesh. Geological Society of America, Abstracts with Programs 38(7):242
Basu AR, Jacobsen SB, Poreda RJ, Dowling CB, Aggrawal PK (2001) Large groundwater strontium flux to the oceans from the Bengal Basin and marine strontium isotope record. Science 293:1470−1473
BGS/DPHE/MML (1999) Groundwater studies for arsenic contamination in Bangladesh, Phase I: Rapid investigation phase. Department of Public Health Engineering, Govt. of Bangladesh, British Geological Survey and Mott MacDonald Ltd., UK
BGS/DPHE/MML (2001) Arsenic contamination of groundwater in Bangladesh, vol. 2: final report, Kinniburgh, D.G., Smedley, P.L. (Eds.). British Geological Survey (BGS) Technical Report WC/00/19, Keyworth
Bhattacharya P, Chatterjee D, Jacks G (1997) Occurrence of arsenic-contaminated groundwater in alluvial aquifers from the delta plain, eastern India: options for a safe drinking water supply. Water Res Develop 13:79–92
Biswas B (1963) Results of exploration for petroleum in the western part of Bengal basin, India. Proceedings of Symposium on Development of Petrology. Mineral Resource Division Service, no. 18(1):241–250
Brammer H (1990) Floods in Bangladesh II: Flood mitigation and environmental aspects. Geogr J 156:158–165
Burgess WG, Burren M, Perrin J, Ahmed KM (2002) Constraints on sustainable development of arsenic-bearing aquifers in southern Bangladesh. Part 1: A conceptual model of arsenic in the aquifer. In: Hiscock KM, Rivett MO, Davison RM (eds.) Sustainable Groundwater Development. Geological Society, London, Special Publications 193, 145–163
Burgess WG, Ahmed KM (2006) Arsenic in aquifers of the Bengal Basin - from sediment source to tubewells for domestic water supply and irrigation. In: Naidu R, Smith E, Owens G, Bhattacharya P, Nadebaum P (Eds.) Managing Arsenic in the Environment: From Soil to Human Health. CSIRO Publishing, Adelaide
Census (2001) Provisional population totals. Census of India, chapter 3, series 1. Government of India
CGWB (1994a) Hydrogeology and groundwater resource of Murshidabad district, West Bengal. Technical Report, series D, Central Ground Water Board (CGWB), Eastern Region, Government of India
CGWB (1994b) Hydrogeology and groundwater resource of Nadia district, West Bengal. Technical Report, series D, Central Ground Water Board (CGWB), Eastern Region, Government of India
CGWB (1994c) Hydrogeology and groundwater resource of North 24 Parganas district, West Bengal. Technical Report, series D, Central Ground Water Board (CGWB), Eastern Region, Government of India
CGWB (1994d) Hydrogeology and groundwater resource of South 24 Parganas district, West Bengal. Technical Report, series D, Central Ground Water Board (CGWB), Eastern Region, Government of India
CGWB (1994e) Hydrogeological atlas of West Bengal, scale 1: 2,000,000. Central Ground Water Board (CGWB), Eastern Region, Government of India
CGWB (1997) High arsenic groundwater in West Bengal. Technical Report, series D, Central Ground Water Board (CGWB), Eastern Region, Government of India
Coleman JM (1969) Brahmaputra River: channel processes and sedimentation. Sediment Geol 3:129–239
Coleman JM (1981) Deltas: processes of deposition and models of exploration, 2nd edition. Burgess, Minneapolis
Cuthbert MO, Burgess WG, Connell L, (2002) Constraints on sustainable development of arsenic-bearing aquifers in southern Bangladesh. Part 2: Preliminary models of arsenic variability in pumped groundwater. Part 1: A conceptual model of arsenic in the aquifer. In: Hiscock KM, Rivett MO, Davison RM (eds.) Sustainable Groundwater Development. Geological Society, London, Special Publications 193, 165–179
Das D, Chatterjee A, Mandal BK, Samanta G, Chakraborti D, Chanda B (1995) Arsenic in groundwater in six districts of West Bengal, India: the biggest arsenic calamity in the world. Part 2: Arsenic concentration in drinking water, hair, nails, urine, skin-scale and liver tissue (biopsy) of the affected people. Analyst 120:917–924
Davies J (1995) The hydrochemistry of alluvial aquifers in central Bangladesh. In: Nash H, McCall GJH (eds.) Groundwater Quality. Chapman & Hall, London, 9–18
Deming D (2002) Introduction to hydrogeology. McGraw-Hill, New York
Dowling CB, Poreda RJ, Basu AR (2003) The groundwater geochemistry of the Bengal basin: weathering, chemsorption, and trace metal flux to the oceans. Geochim Cosmochim Acta 67(12):2117–2136
DPHE/BGS/MML (1999) Groundwater studies for arsenic contamination in Bangladesh, Phase I: Rapid investigation phase. British Geological Survey and Mott MacDonald Ltd., UK
Evans P (1964) The tectonic framework of Assam. J Geol Soc India 5:80–96
Fairbanks RG (1989) A 17,000 glacio-eustatic sea level record: influence of glacial melting rates on the Younger Dryas event and deep ocean circulation. Nature 342:637–642
FAO (1990) Penman-Monteith equation. Food and Agriculture Organization (FAO) method 56 (FAO–56)
Ghosh AR, Mukherjee A (2002) Arsenic contamination of groundwater and human health impacts in Burdwan District, West Bengal, India. Geological Society of America, Abstracts with Programs 34(2):107
Ghosh NC, Chakraborty B, Mazumder PK (1999) Groundwater flow model. Proceedings of Workshop on Groundwater and Its Protection with Special Reference to Arsenic Contamination, Calcutta, CGWB, India
Goodbred SL, Kuehl SA (2000) The significance of large sediment supply, active tectonism, and eustasy on margin sequence development: Late Quaternary stratigraphy and evolution of the Ganges-Brahmaputra delta. Sediment Geol 133:227–248
Goodbred SL, Kuehl SA, Steckler MS, Sarkar MH (2003) Controls on facies distribution and stratigraphic preservation in the Ganges-Brahmaputra delta sequence. Sediment Geol 155(3–4):301–316
Harvey CF (2002) Groundwater flow in the Ganges delta. Science 296:1563
Harvey CF, Swartz CH, Badruzzaman ABM, Keon-Blute N, Yu W, Ali MA, Jay J, Beckie R, Niedan V, Brabander D, Oates PM, Ashfaque KN, Islam S, Hemond HF, Ahmed MF (2002) Arsenic mobility and groundwater extraction in Bangladesh. Science 298:1602–1606
Harvey CF, Swartz CH, Badruzzaman ABM, Keon-Blute N, Yu W, Ali MA, Jay J, Beckie R, Niedan V, Brabander D, Oates PM, Ashfaque KN, Islam S, Hemond HF, Ahmed MF (2005) Groundwater arsenic contamination on the Ganges delta: biogeochemistry, hydrology, human perturbations, and human suffering on a large scale. Cs R Geosci 337(1–2):285–296
Harvey CF, Ashfaque KN, Yu W, Badruzzaman ABM, Ali MA, Oates PM, Michael HA, Neumann RB, Beckie R, Islam S, Ahmed MF (2006) Groundwater dynamics and arsenic contamination in Bangladesh. Chem Geol 228:112–136
Hassan MQ (1992) Saline Water Intrusion and Hydrogeological Modelling in Southwest Bangladesh. Schezky & Jeep, Germany
Horneman A, VanGeen A, Kent DV, Mathe PE, Zheng Y, Dhar RK, O’Connel S, Hoque MA, Aziz Z, Shamsudduha M (2004) Decoupling of As and Fe release to Bangladesh groundwater under reducing conditions. Part I: Evidence from sediment profiles. Geochim Cosmochim Acta 68(17):3459–3473
Hossain AFMA, Siddiqui S, Khan ZH, Hassan M, Sadek S (2003) Development of groundwater modeling at SWMC. In: Rahman AA, Ravenscroft P (eds.) Groundwater resources development in Bangladesh. The University Press, Dhaka, 141–159
Imam MB, Shaw HF (1985) The diagenesis of Neogene clastic sediments from Bengal basin, Bangladesh. J Sediment Petrol 55:665–671
Islam MS, Tooley MJ (1999) Coastal and sea level changes during the Holocene in Bangladesh. Quat Int 55:61–75
Islam MN, Uddin MN (2002) Country paper on hydrogeology section. Proceedings of International Workshop on Arsenic Issue in Bangladesh, 23 pp
JICA (2002) The study on the ground water development of deep aquifers for safe drinking water supply to arsenic affected areas in western Bangladesh. Draft final report, book 1–3. Japan International Cooperation Agency, Kokusai Kogyo Co. Ltd. and Mitsui Mineral Development Engineering Co. Ltd
Lindsay JF, Holiday DW, Hulbert AG (1991) Sequence stratigraphy and the evolution of the Ganges-Brahmaputra complex. AAPG Bull 75:1233–1254
Mace RE (2001) Estimating transmissivity using specific-capacity data. Geological Circular 0102, Bureau of Economic Geology, University of Texas at Austin
Malmstrom VH (1969) A new approach to classification of climate. J Geogr 68:351–357
Maxey GB (1964) Hydrostratigraphic units. J Hydrol 2:124–129
McArthur JM, Ravenscroft P, Safiullah S, Thirlwall MF (2001) Arsenic in groundwater: testing pollution mechanisms for aquifers in Bangladesh. Water Resource Res 37:109–117
McArthur JM, Banerjee DM, Hudson-Edwards KA, Mishra R, Purohit R, Ravenscroft P, Cronin A, Howarth RJ, Chatterjee A, Talukder T, Lowry D, Houghton S, Chadha D (2004) Natural organic matter in sedimentary basins and its relation to arsenic in anoxic groundwater: the example of West Bengal and its worldwide implications. Appl Geochem 19:1255–1293
McDonald MG, Harbaugh AW (1988) A modular three-dimensional finite-difference ground-water flow model. U.S. Geological Survey Techniques of Water-Resources Investigations, book 6, A1
Miah MM (1988) Flood in Bangladesh: A hydromorphological study of the 1987 flood. Academic Publishers, Dhaka
MID (2001) Report of 3rd Minor Irrigation Census in West Bengal 2000–2001. Minor Irrigation Department, Government of West Bengal, India
MMP (1982) Northwest Bangladesh Groundwater Model. Sir M MacDonald & Partners, UK and Bangladesh Agricultural Development Corporation, Government of Bangladesh
Morgan JP, McIntire WG (1959) Quaternary geology of Bengal Basin, East Pakistan and India. Geol Soc Am Bull 70:319–342
MPO (1987) Groundwater Resources of Bangladesh. Technical Report 5, Master Plan Organization (MPO), Dhaka, Harza Engineering, USA, Sir M MacDonald & Partners, UK, Meta Consultants, USA and EPC Ltd, Dhaka
MPO (1990) Description of Groundwater Model Programs. National Water Plan Project Phase II, Master Plan Organization (MPO), Dhaka, Harza Engineering, USA, Sir M MacDonald & Partners, UK, Meta Consultants, USA and EPC Ltd, Dhaka
Mukherjee S (2004) Prerequisite studies for numerical flow modeling to locate safe drinking water wells in the zone of arsenic polluted groundwater in the Yamuna sub-basin, West Bengal, India. Proceedings of 32nd International Geologic Congress, Florence, Italy
Mukherjee A (2006) Deeper groundwater chemistry and flow in the arsenic affected western Bengal basin, West Bengal, India. Unpublished Ph.D. dissertation, University of Kentucky, Lexington
Mukherjee A, Fryar AE (2007) Deeper groundwater chemistry and geochemical evolution modeling of the arsenic affected western Bengal basin, West Bengal, India. Applied Geochemistry (in press)
Mukherjee A, Fryar AE, Rowe HD (2007) Regional scale stable isotopic signature and recharge of the deep water of the arsenic affected areas of West Bengal, India. J Hydrol 334(1–2):151–161
National Climatic Data Center (http://www.ncdc.noaa.gov/oa/pub/data/ghcn/v2/ghcnftp.html), accessed June, 2005
Nickson R, McArthur JM, Ravenscroft P, Burgess WG, Rahman M (1998) Arsenic poisoning of groundwater in Bangladesh. Nature 395:338
Nishat A, Bhuiyan, MA, Saleh FM (2003) Assessment of the groundwater resources of Bangladesh. In: Rahman AA, Ravenscroft P (eds.) Groundwater resources development in Bangladesh. The University Press, Dhaka, 87–114
Penman HL (1948) Natural evaporation from open water, bare soil and grass. Proc Royal Soc London A 193:120–145
PHED (2003a) Tubewell particulars of water supply schemes, district Murshidabad. Public Health Engineering Directorate, Government of West Bengal, Calcutta, India
PHED (2003b) Tubewell particulars of water supply schemes, district Nadia. Public Health Engineering Directorate, Government of West Bengal, Calcutta, India
PHED (2003c) Tubewell particulars of water supply schemes, district North 24 Parganas. Public Health Engineering Directorate, Government of West Bengal, Calcutta, India
PHED (2003d) Tubewell particulars of water supply schemes, district South 24 Parganas. Public Health Engineering Directorate, Government of West Bengal, Calcutta, India
PHED (2004) Map showing arsenic affected blocks in West Bengal. Public Health Engineering Directorate, Government of West Bengal, Calcutta, India
Pike JG (1964) The estimation of annual runoff from meteorological data in a tropical climate. J Hydrol 2:116–123
Rangarajan R, Athvale RN (2000) Annual replenishable ground water potential of India – an estimate based on injected tritium studies. J Hydrol 234:38–53
Ravenscroft P (2003) Overview of the hydrogeology of Bangladesh. In: Rahman AA, Ravenscroft P (eds.) Groundwater resources development in Bangladesh. The University Press, Dhaka, 43–86
Ravenscroft P, McArthur JM, Hoque B (2001) Geochemical and palaeohydrological controls on pollution of groundwater by arsenic. In: Chappell WR, Abernathy CO, Calderon R (eds.) Arsenic exposure and health effects IV. Elsevier, Oxford, pp 53–77
Ravenscroft P, Burgess WG, Ahmed KM, Burren M, Perrin J (2005) Arsenic in groundwater of the Bengal basin, Bangladesh: Distribution, field relations, and hydrogeologic setting. Hydrogeol J 13:727–751
Saha AK (1991) Genesis of arsenic in groundwater in parts of West Bengal. Annual volume, Center for Studies on Man and Environment, Calcutta, India
Sanyal J, Lu XX (2003) Application of GIS in flood hazard mapping: a case study of Gangetic West Bengal, India. Proceedings of Map Asia Conference, GISdevelopment.net
Seaber PR (1988) Hydrostratigraphic units. In: Back W, Rosenshein JS, Seaber PR (eds) The Geology of North America, vol. O–2, Hydrogeology. Geological Society of America pp 9−14
Sengupta S (1966) Geological and geophysical studies in the western part of the Bengal Basin, India. AAPG Bull 50:1001–1017
Sikdar PK, Sarkar SS, Palchoudhury S (2001) Geochemical evolution of groundwater in the Quaternary aquifer of Calcutta and Howrah, India. J Asian Earth Sci 19(5):579–594
Smith AH, Lingas EO, Rahman M (2000) Contamination of drinking-water by arsenic in Bangladesh: a public health emergency. Bull World Health Org 78(9):1093–1103
Survey of India (1971) Map of West Bengal, scale 1: 1000,000. Publishing group of Survey of India, Government of India, Calcutta, India
SWID (1998) A comprehensive hydrogeological information of Murshidabad district. Geologic Division No. III, State Water Investigation Directorate (SWID), Government of West Bengal, Calcutta, India
Tagore R (1905) Amar Sonar Bangla (My Golden Bengal). Baul (Folk Singer), Visva-Bharati Publications, Calcutta, India
Thornthwaite CW (1948) An approach toward a rational classification of climate. Geogr Rev 38:85–94
Tóth J (1963) A theoretical analysis of groundwater flow in small drainage basins. J Geophys Res 68:4795–4812
Uddin MN, Abdullah SKM (2003) Quaternary geology and aquifer systems in the Ganges-Brahmaputra-Meghna delta complex, Bangladesh. Proceedings of South Asian Geological Congress
Umitsu M (1987) Late Quaternary sedimentary environment and landform evolution in the Bengal Lowland. Geogr Rev Japan, Series B, 60:164–178
Umitsu M (1993) Late Quaternary sedimentary environments and landforms in the Ganges Delta. Sediment Geol 83:177–186
UNDP (1982) Groundwater survey: The hydrogeological conditions of Bangladesh. UNDP Technical Report DP/UN/BGD–74–009/1
van Geen A, Ahmed KM, Seddique AA, Shamsudduha M (2003) Community wells to mitigate the current arsenic crisis in Bangladesh. Bull World Health Org 82:632–638
van Wonderen JJ (2003) The use of groundwater models for resource assessment in Bangladesh. In: Rahman AA, Ravenscroft P (eds.) Groundwater resources development in Bangladesh. The University Press, Dhaka, 127–140
von Brömssen M, Jakariya M, Bhattacharya P, Ahmed KM, Hassan MA, Sracek O, Jonsson L, Jacks G (2007) Targeting low-arsenic aquifers in Matlab Upazila, Southeastern Bangladesh. Sci Tot Environ 379(2–3):121–132
WHO (1993) Guidelines for drinking-water quality. Vol. 1 recommendations, 2nd edn. World Health Organization (WHO), Geneva
Acknowledgements
This project could not have been executed without the cooperation of the Public Health Engineering Directorate and State Water Investigation Directorate, Government of West Bengal. However, the ideas presented in this report are those of the authors and have not been officially endorsed by the Government of West Bengal or any other person or organization. Special thanks to P.K. De, A. Banerjee, A. Bhattacharya, G. RoyChowdhury, B. Hazra (PHED); M.K. Sinha (SWID); Dr. S.P. SinhaRoy (Arsenic Core Committee); and the late Prof. A. Chakraborty (Indian Institute of Technology-Kharagpur). The authors are immensely grateful to B.M. Engineering, KrishnaNagar, for supplying lithologs; ESI and the Hydrogeology Division, Geological Society of America, for providing Groundwater Vistas; Terry Lahm, Maura Methany and Martin VanOort for advice on groundwater modeling; and William A. Thomas, Bridget Scanlon, Stephen Workman, Sunil Mehta, Jean Nicot, Holly Michael, and Jan van Wonderen for their advice and informal reviews. The authors also express their gratitude to William Burgess and Peter Ravenscroft for their journal reviews. The project was financially supported by the University of Kentucky (Department of Earth and Environmental Sciences, College of Arts & Sciences, and the Graduate School), the Kentucky NSF-EPSCoR program, and the Geological Society of America (Grant No. 7751–04).
Author information
Authors and Affiliations
Corresponding author
Electronic supplemetary material
Below is the link to the electronic supplementary material.
ESM Fig. 1
Elevation map of the study area prepared from SRTM-90 DEM. Reliable elevation data were not available from the area marked as Sunderbans(mangrove forest) because of vegetation cover (GIF 3993 kb)
ESM Fig. 2
Modeled plan maps of the study area showing the subsurface distribution of lithologic units of definite depths (GIF 839 kb)
Rights and permissions
About this article
Cite this article
Mukherjee, A., Fryar, A.E. & Howell, P.D. Regional hydrostratigraphy and groundwater flow modeling in the arsenic-affected areas of the western Bengal basin, West Bengal, India. Hydrogeol J 15, 1397–1418 (2007). https://doi.org/10.1007/s10040-007-0208-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10040-007-0208-7