Estimating the radiological risks resulting from treating produced water by wetlands technique

Abstract

In the current study, the radiation dose and risk resulting from the treatment of of co-produced water with oil containing naturally occurring radioactive materials were determined using the wetland technique. Calculation of the activity concentration of radium-226 (²²⁶Ra) deposited assuming that the daily rate of removal from co-produced water in the wetlands is (0.8×10⁵ m³) and that the activity concentration of  ²²⁶Ra in the water is approximately (2 Bq/L). The calculation showed that the activity concentration in the treatment ponds was about (33.6 Bq/kg) in one year. The RESRAD program was used to evaluate the total radiation dose that workers in the wetland project might receive. In this case, the results showed that none of the workers in this project would receive an annual dose greater than (1) msv/year, which is mainly caused by external exposure to radiation. It was also found that the radiation dose and the risk resulting from internal exposure to radon gas and plankton are negligible, and the radiation dose increases with the increase in the concentration of radium-226 in the accompanying water, which can reach (100) Bq/L. Given the low concentration of radium-226 deposited, the radioactive risks associated with the project during the normal treatment process are small and can be neglected.