title: Radiological assessment of water treatment processes in a water treatment plant in Saudi Arabia: Water and sludge radium content, radon air concentrations and dose rates.
abstract: There is an increase demand for clean water sources in Saudi Arabia and, yet, renewable water resources are very limited. This has forced the authorities to explore deep groundwater which is known to contain large concentrations of radionuclides, mainly radium isotopes. Lately, there has been an increase in the number of water treatment plants (WTPs) around the country. In this study, a radiological assessment of a WTP in Saudi Arabia was performed. Raw water was found to have total radium activity of 0.23Bq/L, which exceeds the international limit of 0.185Bq/L (5pCi/L). The WTP investigated uses three stages of treatment: flocculation/sedimentation, sand filtration and reverse osmosis. The radium removal efficiency was evaluated for each stage and the respective values were 33%, 22% and 98%. Moreover, the activity of radium in the solid waste generated from the WTP in the sedimentation and sand filtrations stages were measured and found to be 4490 and 6750Bq/kg, respectively, which exceed the national limit of 1000Bq/kg for radioactive waste. A radiological assessment of the air inside the WTP was also performed by measuring the radon concentrations and dose rates and were found in the ranges of 2-18Bq/m(3) and 70-1000nSv/h, respectively. The annual effective dose was calculated and the average values was found to be 0.3mSv which is below the 1mSv limit.
authors.affiliation: Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia. Electronic address: qjassem@kacst.edu.sa.
authors.forename: Q Kh
authors.initials: QKh
authors.lastname: Al-Jaseem
authors.affiliation: Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia.
authors.forename: Fahad I
authors.initials: FI
authors.lastname: Almasoud
authors.affiliation: Physics Dept., Faculty of Science, Islamic University in Madinah, Al-Madinah, P.O. Box 170, Saudi Arabia.
authors.forename: Anas M
authors.initials: AM
authors.lastname: Ababneh
authors.affiliation: Nuclear Science Research Institute (NSRI), King Abdulaziz City for Science and Technology (KACST), P.O. Box 6086, Riyadh 11442, Saudi Arabia.
authors.forename: A S
authors.initials: AS
authors.lastname: Al-Hobaib
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D006801:Humans; D016273:Occupational Exposure; D011829:Radiation Dosage; D000069079:Radiation Exposure; D011834:Radiation Monitoring; D011883:Radium / Q000032:analysis*; D012529:Saudi Arabia; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D018508:Water Purification / Q000379:methods*; D014881:Water Supply
chemical_list: D000396:Air Pollutants, Radioactive; D014875:Water Pollutants, Radioactive; D011883:Radium
keywords: Flocculation; RO; Radioactivity; Sludge; Water treatment