Radiological hazard Assessment Due to Natural Occurring Radioactive Materials (NORM) in Oil and Gas Production Industry –East Baghdad Oil Field

Abstract

Concentration of NORM then radiological hazard indices were investigated and assessed in different stages of oil and gas production industry that belongs to East Baghdad Oil Field. Sixteen samples of different types of materials were collected representing oil and gas production from first stage to final stage. The samples are prepared then sent to Radiation Protection Center (RPC) / Ministry of Environment for radioactivity analysis using gamma ray spectrometry system based on HPGe. The results show that max value of Ra-226 is 252.4 Bq/kg in sediment sample collected from the final stage of water treatment before it is transferred to disposal well and min value is 1.2 Bq/kg in formation water. The max. activity of Th-232 is 79.4Bq/kg also in sediment sample and the min value 2.9 Bq/Kg in crude oil in storage tank while, the max. value for K-40 is 529.6 Bq/Kg in burning stage (burn pit) and the min value is 2.8Bq/kg in Pre-treatment crude oil. The ambient exposure dose values near the sampling locations were recorded using dosimeter type GMC-300. The results are corresponding with the values of NORMs in the locations. The ambient gamma rates in the study area range between (0.04-0.22) μSv/h corresponding to (57-314 nGray/h). Most locations have values above the average worldwide value of (58 nGray/h). NORMs are caused absorbed dose in max. contribution (79%) to the total ambient gamma dose. Radium caused the max. contribution among the others. All the hazard indices indicate that most of the sampling locations have indices acceptable and with no hazard.