Chemical fractionation of radium-226 in NORM contaminated soil from oilfields.
Contamination of soil with226Ra is a common problem in the oilfields, leading to costly remediation and disposal programmes. The present study focuses on the chemical fractionation and mobility of226Ra in contaminated soils collected from an oilfield using a three-step sequential extraction procedure (BCR). The total activity concentrations of226Ra 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 of226Ra and soil properties, mainly pH, LOI, Corg, clay and Ca, was investigated using the principal component analysis method (PCA). The chemical fractionation of226Ra was studied using the sequential extraction method (BCR). The highest fraction of226Ra (27-65%) was found to be in the acid-reducible fraction, which suggests that226Ra is mainly bound to FeMn oxides. The BCR method showed that high percentages of226Ra were found to be in mobile soil phases (between 45 and 99%). Consequently, groundwater contamination could occur due to the remobilization of226Ra 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.
Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091, Syrian Arab Republic. Electronic address: prscience12@aec.org.sy.
Jamal
J
Al Abdullah
Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091, Syrian Arab Republic.
Mohammad Said
MS
Al-Masri
Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091, Syrian Arab Republic.
Yusr
Y
Amin
Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091, Syrian Arab Republic.
Ibrahim
I
Awad
Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091, Syrian Arab Republic.
Zuhair
Z
Sheaib
D005591:Chemical Fractionation / Q000379:methods*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D061329:Oil and Gas Fields; D011883:Radium / Q000032:analysis / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012990:Soil Pollutants, Radioactive / Q000032:analysis / Q000737:chemistry*
D012987:Soil; D012990:Soil Pollutants, Radioactive; D011883:Radium
(226)Ra; Contaminated soil; Mobility; NORM; Oilfields; Sequential extraction