Evaluation of radiation hazard potential of TENORM waste from oil and natural gas production

In this study, a potential radiation hazard from TENORM sludge wastes generated during exploration and extraction processes of oil and gas was evaluated. The activity concentration of natural radionuclides 238U, 226Ra and 232Th were determined in TENORM sludge waste. It was found that sludge waste from oil and gas industry is one of the major sources of 226Ra in the environment. Therefore, some preliminary chemical treatment of sludge waste using Triton X-100 was also investigated to reduce the radioactivity content as well as the risk of radiation hazard from TENORM wastes. The activity concentrations of 226Ra and 228Ra in petroleum sludge materials before and after chemical treatment were measured using gamma-ray spectrometry. The average values of the activity concentrations of 226Ra and 228Ra measured in the original samples were found as 8908 Bq kg−1 and 933 Bq kg−1, respectively. After chemical treatment of TENORM samples, the average values of the activity concentrations of 226Ra and 228Ra measured in the samples were found as 7835 Bq kg−1 and 574 Bq kg−1, respectively. Activity concentration index, internal index, absorbed gamma dose rate and the corresponding effective dose rate were estimated for untreated and treated samples.