RADON (222Rn) OCCURRENCE IN QUATERNARY DEPOSITS, ANNUAL DOSAGE AND GROUNDWATER RECIRCULATION IN HASHYIMIA, BABYLON, IRAQ

Najah M.L. Al-Maimuri; Kamal K. Ali; Muhsen K. Hasson; Mohammed K. Abed

Najah M.L. Al-Maimuri Institute of Technology in Babylon
Kamal K. Ali College of Science, University of Baghdad
Muhsen K. Hasson 2Department of Environment, University of babil, Babil, Iraq
Mohammed K. Abed Institute of Technology in Babylon

Keywords: Piezometric Velocity, Infection, Residence time, Annual dosage, Recirculation

Abstract

During many tests on ground water sample that were carried out in the labs of Babylon environment directorate, Radon among many pollutants was encountered in concentrations exceeded the allowable limits according to WHO. Hashyimia unconfined aquifer with an area of about 100 Km2 was found to be polluted with Radon (222Rn) with concentrations exceed the maximum permitted value according to WHO (100 Bq/liter) in many locations. Preliminary tests with Alpha GUAR PQ2000 PRO, Alpha PUMP and Aqua KIT device of many GW samples reveal that their concentrations reach 113 Bq/liter after 3 hrs since a continuous pumping start. Geologically Hashyimia is consisted of a quaternary deposits of unconsolidated and finer grained of flood plains of the Euphrates River which mainly consist of clay, silt, sand and gypsum layers. A mathematical estimation of GW velocity (<1 cm/day) proved that 222Rn origin is created by the local geologic formation of the aquifer and instantaneously the aquifer endures concentrations rise during the pumping process. It is found that the annual dosage reaches (453 SV year-1) with residence time of (12 day-1). A mathematical model has been designed to simulate and execute the theory of GW recirculationand purification against 222Rn infection using the property of radon releasing during an exposure to air.The results indicates that 216 and 112
pumping and injecting wells are needed to recycle 100% strategic GW storage of the selected polluted sector respectively. It is concluded that 222Rn is instantaneously produced by unknown source around the pumping well during a continuous pumping process and its concentration increases to a constant values.