Variations of Ra-226, Ra-228 and K-40 activity concentrations along Linggi River Yii, M.W. and Zal U’yun Wan Mahmood Malaysian Nuclear Agency, 43000 Kajang, Selangor, MALAYSIA ABSTRACT INTRODUCTION Study presented the concentration distribution of Uncontrolled development and rapid Ra-226, Ra-228 and K-40 in sediment and water industrialization brought alarming level of and its variation related to the physical parameters pollutants into the aquatic environment. Water and suspended particles to find the dynamics of and sediment can be used as an indicator to these radionuclides along the river. Also, the determine the level of pollutants. According to changing trend of radionuclides activity along the Environment Quality Report 2006 by river will provide information of pollutants Department of Environment, even though Linggi movement from terrestrial to estuary. River in Negeri Sembilan is not categorized as very much polluted as several rivers, but it has OBJECTIVES been selected to be the study site because this •To find relation between radionuclides river lies within the catchment area of 1,250 concentration with physical parameters. kilometer square and it was used as one of the •To identify pollutants movement from terrestrial water supply intake point for Seremban, Rembau to estuary. and Port Dickson Districts. MATERIAL AND METHODS RESULTS Study Area Analyses flow Activity concentrations w in Water a t e r Activity concentrations in Sediment Physical Data of water S e d i m e n t Correlation of radionuclides in sample CONCLUSION Activity of radionuclides at some stations are found to be higher than the others mainly suggesting the input of radium (development and excavation of soil) and potassium (agriculture) is coming from human activities. The almost unity value for radium isotopes in sediment suggesting that the source in both river streams very likely are coming from the same origin. Nuclear Malaysia Technical Convention, 3rd – 5th November 2015 .