Study of the Level of Environmental Radioactivity In The South-Eastern Part of The Shazand Refinery Complex

Minerals, including crude oil, contain a small amount of natural radioactive elements. During the refining of crude oil and production of petroleum derivatives, appropriate waste is burnt by burners, and impurities are dispersed in the form of fly ash, which after cooling settles in the surrounding environment [1-3]. This, in turn, is a function of wind flow, ambient temperature, and topography of the region. In this region, 80% of the winds are from the west to the east, and the Rasvand and Sefidlkhani mountains are in the west and southeast of the refinery respectively, causing air stagnation along the mountains. Therefore, to constantly monitor the environment, it is necessary to examine the soil and crops in the environment and determine their radioactivity. In this study to determine the radioactivity in the agriculture lands of Baghbaraftab and Ghadamgah has been carried out for determining the radiation level and to measure the radiation dose exposure to farmers and inhabitants of the studied area. The villages of Baghbaraftab and Ghadamgah are located 5 km southeast of the Shazand Refinery Complex. The Shazand Refinery Complex is one of the largest plants in Iran, which lies 30 km west of the Arak metropolis. Twenty-one soil samples have been collected from two different lands. Sampling spots in the each land have been selected for the assessment of specific activities of radionuclides of 226Ra, 232Th, 40K and137Cs using high purity germanium detector set up. Standards IAEA references material RGU, RGTh and RGK were used for quality control and determining efficiency calibration [4]. The specific activities of corresponding radionuclides varied from13.12 to 33.03, 11.3 to 35.86, 257.82 to 605.5 and 1.28 to 13.36 in Bq/kg respectively. The levels of artificial radionuclide 137Cs are consist with other measurements in this region [5]. Radium equivalent value and radiological parameters were calculated for all samples. Results were found to be within the global reported safety limits [6]. Therefore, there is no risk for farmers and residents of this region.