Chemical fractionation of radium-226 in NORM contaminated soil from oilfields. (December 2016)

• Record Type: Journal Article
• Authors: Al Abdullah, Jamal; Al-Masri, Mohammad Said; Amin, Yusr; Awad, Ibrahim; Sheaib, Zuhair
• Is Part Of: Journal of environmental radioactivity. Volume 165(2016:Dec.)
• Page Start: 47
• Page End: 53
• Publication Date: 2016-12
• Subjects: Contaminated soil -- 226Ra -- NORM -- Sequential extraction -- Mobility -- Oilfields; Radioactivity -- Periodicals; Radiation, Background -- Periodicals; Radioecology -- Periodicals; Radioactive pollution -- Periodicals; Environmental Pollutants -- Periodicals; Radioactive Pollutants -- Periodicals; Radioactivity -- Periodicals; Radioécologie -- Périodiques; Pollution radioactive -- Périodiques; Fond de rayonnement -- Périodiques; 539.752
• DOI: 10.1016/j.jenvrad.2016.09.003
• Languages: English
• ISSNs: 0265-931X

Abstract

Abstract: Contamination of soil with 226 Ra is a common problem in the oilfields, leading to costly remediation and disposal programmes. The present study focuses on the chemical fractionation and mobility of 226 Ra in contaminated soils collected from an oilfield using a three-step sequential extraction procedure (BCR). The total activity concentrations of 226 Ra in contaminated soils were measured and found to be in the range from 1030 ± 90 to 7780 ± 530 Bq kg −1, with a mean activity concentration of 2840 ± 1840 Bq kg −1 . The correlation between the total concentration of 226 Ra and soil properties, mainly pH, LOI, Corg, clay and Ca, was investigated using the principal component analysis method (PCA). The chemical fractionation of 226 Ra was studied using the sequential extraction method (BCR). The highest fraction of 226 Ra (27–65%) was found to be in the acid-reducible fraction, which suggests that 226 Ra is mainly bound to FeMn oxides. The BCR method showed that high percentages of 226 Ra were found to be in mobile soil phases (between 45 and 99%). Consequently, groundwater contamination could occur due to the remobilization of 226 Ra from soils under normal environmental conditions. However, the obtained results could be useful to reduce the volume of NORM wastes generated from the oilfields and decision-making process for final treatment and disposal of NORM-contaminated soil. Highlights: Activity concentrations of 226Ra were measured in soils from a dried evaporation pit. A sequential extraction procedure (BCR) was performed to NORM contaminated soils. A high mobility of 226Ra was noted and mainly found in acid-reducible fraction. The chemical treatment can be used to extract 226Ra from NORM contaminated soils.