ABSTRACT Groundwater is the main source of water in arid and semi-arid regions. Therefore, pollution of groundwater is a major issue because aquifers and the contained groundwater are inherently susceptible to contamination from wastewater and agricultural activities. Aquifer vulnerability has been assessed in the Sana’a basin using the DRASTIC method, based on a Geographic Information System (GIS). The DRASTIC model uses seven environmental parameters (Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity) to characterize the hydrogeological setting and evaluate aquifer vulnerability. A regional scale aquifer vulnerability map of the basin was prepared using overlay analysis with the aid of GIS. A DRASTIC vulnerability map, verified by data of nitrate in groundwater, shows that the defined areas are compatible with land-use data. It is concluded that 6.4% of the basin area is highly vulnerable and urgent pollution-preventions measures should be taken for every kind of relevant activity within the whole basin.
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nullY. Alwathaf and B. Mansouri, "Assessment of Aquifer Vulnerability Based on GIS and ARCGIS Methods: A Case Study of the Sana’a Basin (Yemen)," Journal of Water Resource and Protection, Vol. 3 No. 12, 2011, pp. 845-855. doi: 10.4236/jwarp.2011.312094.
 D. Thirumalaivasan, M. Karmegam and K. Venugopal, “AHP-DRASTIC: Software for Specific Aquifer Vulner- ability Assessment Using DRASTIC Model and GIS,” Environmental Model & Software, Vol. 18, No. 7, 2003, pp. 645-656. doi:10.1016/S1364-8152(03)00051-3
 J. Margat, “Groundwater Vulnerability to Contamination,” Bases de la Cartographie, Doc. 68 SGC 198 HYD, BRGM, Orleans, 1968.
 L. Aller, T. Bennet, J. H. Leher, R. J. Petty anf G. Hack- ett, “DRASTIC: A Standardized System For Evaluating Ground Water Pollution Potential Using Hydrogeological Settings,” EPA 600/2-87-035, 1987, p. 622.
 S. Foster, “Fundamental Concept in Aquifer Vulnerability, Pollution Risk and Protection Strategy,” In: W. Van Dui- jvenbooden and H. G. Van Waegeningh, Eds., Vulnera- bility of Soil and Groundwater to Pollutions. Committee on Hydrogeological Research, Hague, 1987, pp. 69-86.
 D. Van Stempvoort, L. Ewert and L. Wassenaar, “Aquifer Vulnerability Index (AVI): A GIS Compatible Method gor Groundwater Vulnerability Mapping,” Canadian Wa- ter Resource Journal, Vol. 18, No. 1, 1993, pp. 25-37.
 M. Civita “Contamination Vulnerability Mapping of the Aquifer: Theory and Practice,” Quaderni di Tecniche di Protezione Ambientale, Pitagora, 1994.
 J. Vrba and A. Zoporozec “Guidebook on Mapping Ground- water Vulnerability,” IAH International Contribution for Hydrogeology, Hannover 7 Heise, Vol. 16, 1994. p. 131.
 R. Gogu and A. Dassargues, “Current Trends and Future Challenges in Groundwater Vulnerability Assessment Us- ing Overly and Index Methods,” Environmental Geology, Vol. 36, No. 6, 2000, pp. 549-559.
 N. Doerfliger, P. Y. Jeannin and F. Zwahlen “Water Vul- nerability Assessment in Karstic Environment: A New Method of Defining Protection Areas Using a Multi-At- tribute Approach and GIS Tools (EPIK Method),” Envi- ronmental Geology, Vol. 39, No. 2, 1999, pp. 165-176.
 N. Doerfliger and F. Zwahlem “Groundwater Vulnerabil- ity Mapping in Karstic Regions (EPIK): Application to Groundwater Protection Zones,” Swiss Agency for the Envi- ronment, Forests and Landscape (SAEFL), Bern, 1998.
 N. Goldscheider, M. Klute, S. Sturm and H. Hotezl, “The PI Method: A GIS-Based Approach to Mapping Ground- water Vulnerability with Special Consideration of Karst Aquifers,” Zeitschrift für Angewandte Geollgie, Vol. 46, No. 3, 2000, pp. 157-166
 J. M. Vias, B. Andreo, M. J. Perles, F. Carrasco, I. Va- dillo and P. Jimenez, “Proposed Method for Groundwater Vulnerability Mapping in Carbonate (Karstic) Aquifers: The COP Method. Application in Two Pilot Sites in Sou- thern Spain,” Hydrogeology Journal, Vol. 14, No. 6, 2006, pp. 912-925.
 J. M. Vias, B. Andreo, M. J. Perles and F. Carrasco, “A Comparative Study of Four Schemes for Groundwater Vulnerability Mapping in a Diffuse Flow Carbonate Aq- uifer Under Mediterranean Climatic Condition,” Environmental Geology, Vol. 47, No. 4, 2005, pp. 586-595.
 J. W. Merchant, “GIS-Based Groundwater Pollution Ha- zard Assessment: A Critical Review of the DRASTIC Mo- del,” Photogrammetric Engineering & Remote Sensing, Vol. 60, No. 9, 1994, pp. 1117-1127.
 A. J. Melloul and M. Collin, “A Proposed Index For Aqui- fer Water Quality Assessment: The Case of Isreal’s Sha- ron Region,” Journal of Environmental Management, Vol. 54, No. 2, 1998, pp. 131-142.
 Y. Kim and S. Hamm, “Assessment of Potential for Ground- water Contamination Using the DRASTIC/EGIS Tech- nique, Cheongju Area, South Korea,” Hydrogeology Jour- nal, Vol. 7, No. 2, 1999, pp. 227-235.
 E. Cameron and G. F. Peloso, “An Application of Fuzzy Logic to the Assessment of Aquifers’ Pollution Potential,” Environmental Geology, Vol. 40, No. 11-12, 2001, pp. 1305-1315.
 T. Al-Zabet, “Evaluation of Aquifer Vulnerability to Con- tamination Potential Using the DRASTIC Method,” En- vironmental Geology, Vol. 43, No. 1-2, 2002, pp. 203-208.
 R. A. N. Al-Adamat, I. D. L. Foster and S. M. J. Baban, “Groundwater Vulnerability and Risk Mapping for the Basaltic Aquifer of the Azraq Basin of Jordan Using GIS, Remote Sensing and DRASTIC,” Applied Geography, Vol. 23, No. 4, 2003, pp. 303-324.
 H. Baalousha, “Vulnerability Assessment for the Gaza Strip Palestine Using DRASTIC,” Environmental Geology, Vol. 50, No. 3, 2006, pp. 405-414.
 A. Jamrah, A. A. Futaisi, N. Rajmohan and S. Al-Yaroubi, “Assessment of Groundwater Vulnerability in Coastal Region of Oman Using DRASTIC Index Method in GIS Environment,” Environmental Monitoring and Assess- ment, Vol. 147, No. 1-3, 2007, pp. 125-138.
 S. Secunda, M. Collin and A. J. Melloul, “Groundwater Vul- nerability Assessment Using a Composite Model Com- bining DRASTIC with Extensive Land Use on Israel’s Sharon Region,” Journal of Environmental Management, Vol. 54, No. 1, 1998, pp. 39-57.
 S. Lee, “Evaluation of Waste Disposal Site Using DRAS- TIC System in Southern Korea,” Environmental Geology, Vol. 44, No. 6, 2003, pp. 654-664.
 J. A. Mendoza and G. Barmen, “Assessment of Groundwater Vulnerability on the Rio Artiguas Basin, Nicaragua,” Environmental Geology, Vol. 50, No. 4, 2006, pp. 569-580.
 Y. Wang, B. J. Merkel, Y. Li, H. Ye, S. Fu abd D. Ihm, “Vulnerability of Groundwater in Quaternary Aquifers to Orginaic Contamination: A Case Study on Wuhan City, China,” Environmental Geology, Vol. 53, No. 3, 2007, pp. 479-484. doi:10.1007/s00254-007-0669-y
 L. Rosen, “A Study of the DRASTIC Methodology with Emphasis on Swedish Condition,” Ground Water, Vol. 32, No. 2, 1994, pp. 278-285.
 Z. Hrkal, “Vulnerability of Groundwater to Acid Deposi- tion, Jizerske Mountains, Northern Czech Republic: Con- struction and Reliability of a GIS-Based Vulnerability Map,” Hydrogeology Journal, Vol. 9, No. 4, 2001, pp. 348-357. doi:10.1007/s100400100141
 M. G. Rupert, “Calibration of the DRASTIC Groundwater Vulnerability Mapping Method,” Ground Water, Vol. 39, No. 4, 2001, pp. 625-630.
 I. R. Lake, A. A. Lovett and K. M. Hiscock, “Evaluating Factors Influencing Groundwater Vulnerability to Nitrate Pollution: Developing the Potential of GIS,” J Journal of Environmental Management, Vol. 68, No. 3, 2003, pp. 315-328. doi:10.1016/S0301-4797(03)00095-1
 G. P. Panagopoulos, A. K. Antonakos and N. J. Lambrakis, “Optimization of the DRASTIC Method for Groundwater Vulnerability Assessment via the Use of Simple Statisti- cal Method and GIS,” Hydrogeology Journal, Vol. 14, No. 6, 2006, pp. 894-911. doi:10.1007/s10040-005-0008-x
 A Rahman, “A GIS Based DRASTIC Model for Assess- ing Groundwater Vulnerability in Shallow Aquifer in Ali- garh, India,” Applied Geography, Vol. 28, No. 1, 2008, pp. 32-53. doi:10.1016/j.apgeog.2007.07.008
 M. Al-Hamdi “Competition for Scarce Groundwater in the Sana’a Plain, Yemen, a Study on the Incentive Sys- tems for Urban and Agricultural Water Use,” IHE Ph.D. Thesis, Balkema Publishers, ISBN 90 5410 4260. 2000
 Italconsult, “Water Supply for Sana’a and Hodeida. Sana’a Basin Groundwater Studies,” Vol. 1-2, UNDP: Yemen 3202, Rome, 1973.
 G. P. Kruseman and L. Vasak, “Wellfield Investigations Kohlan and Wajid Sandstone 1996,” SAWAS Technical Report No.08. 111, Yemen Arab Republic, 1996.
 J. W. A. Foppen, “Source for Sana’a Water Supply, SA- WAS Project; Evaluation of the Effects of Groundwater Use on Groundwater Availability in the Sana’a Basin,” Volume II: Data Availability, SAWAS Technical Report No.05, 1996.
 Survey Authority, “Topographic Map Scale 1:50000,” Re- public of Yemen, 1998.
 NWRA, “Groundwater level map scale 1:250000,” Re- public of Yemen, 2006.
 WEC, “Wells Inventory in the Sana’a Basin, Water and Environment Center at Sana’a University Sana’a Basin Water Resources Management Study,” Final Report, 2002.
 WHO, “Guidelines for Drinking Water Quality,” Adden- dum to Vol. 2, 2nd Edition, Health Criteria and Other Sup- porting Information (WHO/EOS/98.1), World Health Or- ganization, Geneva, 1998.