Determination of Radium, Uranium and 222Rn in groundwater Samples from Different Regions in Saudi Arabia

A.Al–Muqrin; H. Al–Ghamdi; A.El–Sharkawy

Volume : V, Issue : XI, November - 2015

Determination of Radium, Uranium and 222Rn in groundwater Samples from Different Regions in Saudi Arabia

A. Al Muqrin, H. Al Ghamdi, A. El Sharkawy

Abstract :

<p>&nbsp;Surveillance monitoring in different regions of the Saudi Arabian Kingdom (KSA) has been carried out to determine the activity levels of radium isotopes (226Ra and 228Ra), 222Rn and uranium isotopes (234U and 238U) in groundwater samples collected from selected wells. Several techniques were exploited in the radioanalysis methods; the radon&ndash;222 was measured through its daughter Po&ndash;218, with a silicon alpha detector (RAD&ndash;7), the activity concentrations of 234U and 238U isotopes were determined using a surface barrier alpha detector, preceded by a radiochemical separation of both isotopes using extraction chromatography. The radium isotopes were measured by gamma spectrometry using high purity germanium detectors, after radiochemical separation of the isotopes with ionexchange chromatography using a strong cation exchange resin. Quality assurance and methods validation were established through the efficiency caliation of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference samples and the intercomparison with other international laboratories. The average activity concentrations of 226Ra and 228Ra were 6.3 and 6.9 pCi/L respectively, and the relatively higher values of radium activities were found in Qaseem, Hail and Tabouk. The average activity concentration of Rn&ndash;222 was 182.0 pCi/L, which is below the maximum contaminant level proposed by EPA for drinking water (300 pCi/L). The average activity concentration of 234U and 238U were 48.8 and 36.0 mBq/L respectively. The uranium activity ratio (234U/238U) in the investigated samples had an average value of 1.6. The data obtained from the activity concentrations of the investigated radioisotopes are comparable to the results reported in literature for radium, uranium and radon in the Kingdom of Saudi Arabia, and can be used to establish a radiological baseline radioactivity map for uranium, radium and radon radioactivity levels in groundwater of these regions.</p>