The Radiological Contamination in AL-Tahreer Tower Building at Baghdad City

摘要

In this study, evaluation of the radioactivity for AL-Tahreer Tower Building (the Turkish restaurant previously) which located in the center of Baghdad city was implemented. The contamination resulted from bombing the Building by the depleted uranium projectiles. The building consists of 14 floors besides the basement. Radiological characterization was implemented using field and laboratory measurements. The results of radiological surveys by using portable survey meter (CAB-counts per second (cps)) indicated the presence of contaminated soil reached to 60 cps (more than 120 the background radiation level) in addition to the presence of small particles of depleted uranium shells with high levels of contamination reached to 90 cps, compare with (0.5 cps) the background level. While the results of maximum exposure dose rates were 0.6 μSv/hr when the detector of survey meter (Ludlum) put on the contaminated regions at a distance about (0.5 cm). The natural background level of the building at distance one meter was 0.9 μSv/hr. Soil samples had been collected and prepared for measuring according to the international standards and specifications, using gamma spectrometry system which consist of High-purity Germanium Detector with efficiency of 40% and resolution 2.0 keV for Energy 1.332 MeV of ~(60)Co, The laboratory results indicated the presence of high concentrations of Th-234 and Pa-234m isotopes (1550.1 & 3179 Bq/kg respectively) in the soil samples taken from the floors, while the concentrations of Th-234 in natural background soil sample were nearly 40 Bq/kg, Pa-234m not detected. According to the results of radiological characterization (field and laboratory), which showed an increase in radioactivity in the AL-Tahreer Tower Building the protective procedures had been adopted, where the contaminated soil and wastes resulted from decontamination processes collected in the 26 drum of capacity 220 liter, after the transfer of drums to the temporary storage at Tuwaitha site with cooperation of the Directorate of Radioactive Waste Management & Treatment at (MOST). Now the building within the background radiation levels and released by the regulatory body "Radiation Protection Center (RPC)/Ministry of Environment (MOEN)".