Assessing the legacy of radioactive contamination in soil from produced water spills in the Permian Basin of New Mexico
摘要
This paper measured U-Th decay series radionuclide concentrations in soil affected by oil and gas wastewater spills in the Permian Basin of Southeastern New Mexico. In the affected soils, the concentrations of 226Ra ranged from 43.9 to 162.1 Bq kg−1, while 228Ra varied from 16.1 to 78.1 Bq kg−1. Additionally, 224Ra was found between 13.9 and 30.4 Bq kg−1. The corresponding concentrations of 226Ra, 228Ra, and 224Ra in the background soils ranged from 4.9 to 18.6 Bq kg−1, 5.5–13.3 Bq kg−1, and 5.7–12.7 Bq kg−1, respectively, indicating accumulation of radium in affected soils after the spill. Two age dating models, 228Th/228Ra (or 224Ra/228Ra) and 228Ra/226Ra, were used to estimate the age of this accumulation.