Trends in Applied Sciences Research1819-35792151-7908Science International10.3923/tasr.2011.1.18I. Al-ZarahAbdullah 1201161A study was conducted to evaluate the elemental and geochemistry of groundwater aquifer in Al-Ahsa Oasis Eastern region, Saudi Arabia. Total Dissolved Solids (TDS) varies from 2250-3500 mg L-1 in the study area. The concentration order of cations was Na>Mg>Ca and K in descending order and the anion concentration order was Cl>SO4>HCO3. The groundwater and the spring waters were classified as C3S1 to C4S2, i.e., high salinity and medium sodium to very high salinity to high sodium waters. The groundwater of Al-Ahsa is unsaturated with respect to calcite, dolomite, gypsum, anhydrite, halite and oversaturated with respect to goethite and hematite minerals. The hardness of groundwater is very high as compared to the established standards for domestic use. The Fluoride (F) contents are within permissible limits for drinking water. The nitrate contents are within permissible limits for domestic use. Two water types, i.e., Na-Ca-Cl-SO4 and Na-Ca-Mg-Cl-SO4 dominate the groundwater aquifer in Al-Ahsa Oasis. Crop irrigation with groundwater will not create any soil salinity and soil permeability problems. Overall, the review study highlighted the important elemental composition and geochemistry of groundwater of Al-Ahsa Oasis.]]>Al-Barrak, S.A.,19931993Al-Hawas, I.A.,20025651655Appelo, C.A.J. and D. Postma,1994pp: 311-313pp: 311-313Al-Kuwaiti, K. and S. Ahmed,20032003Al-Mohandis, A.A.,199143277283Al-Naeem, A.A.,200811244249Al-Taher, A.A.,1999pp: 1-385pp: 1-385Al-Zarah, A.I.,200811332341Ayers, R.S. and D.W. Westcot,1985pp: 174pp: 174Blaszyk, T. and J. Gorski,1981192833Ball, J.W. and D.K. Nordstrom,1992pp: 189pp: 189BRGD,1976BRGM ,19771977BRGD,1977GDC,19801980Anonymous,19841984Hussain, G. and M. Sadiq,199157-58773783Italconsult,1969Lin, M.T.,19841984Anonymous,1978Anonymous,1979Lin, F. and C. Clemency,19802 partial pressure.]]>1980Ministry of Agriculture and Water,1992Vol. 7,Naimi, A.I.,19651965Parkhurst, D.L.,19951995Ronge, B. and T. Cleasson,1982Bergarters och minerals L. slight I hetvatten (Water-Rock interactions at elevated temperatures).]]>1982USDA.,1954USDA Handbook No. 60,Pages: 160Pages: 160Vidal, F.S.,19511951Water Atlas of Kingdom of Saudi Arabia,19851985Wakuti,1964Vol. 4,WHO,1984Vol. 2,WHO,19931993HIDA,19841984Fathi, A.A. and M.A. Al-Kahtani,20095434443