Specific Activity and Radioactive Contour Map of Anthropogenic Radionuclide (137Cs) in Surface Soil Samples from Chumphon Province, Thailand

Specific activities of anthropogenic radionuclide (Cs-137) were studied and determined in 132 surface soil samples collected from 8 districts in Chumphon province in the south of Thailand. A high resolution high-purity germanium (HPGe) detector with a massive lead shield and gamma spectrometry analysis system were employed to measure the gamma ray energy spectra from the samples. The specific activity of Cs-137 in all of surface soil samples were analyzed by using the IAEA/SL-2 radioactive standard source. It was found that the specific activities of Cs-137 ranged from < 0.33 - 4.43 Bq/kg with mean values of 2.30 +/- 1.38 Bq/kg. The experimental results were also compared with research data in the south of Thailand (2009 - 2012), Office of Atoms for Peace (OAP) annual report data and global radioactivity measurement and evaluations. The data can be also used to create the radioactive contour maps of the investigated area.