Assessment of radioactivity levels and radiological hazards in soils surrounding a rare earth waste residue dump in northeast China

Abstract

This study evaluated the activity concentrations of naturally occurring radionuclides ( ²³² Th, ²²⁶ Ra, and ⁴⁰ K) and their associated radiological hazard indices, in soils surrounding a rare earth waste residue pile in Northeast China. The mean activity concentrations for ²³² Th, ²²⁶ Ra, and ⁴⁰ K were 36.7, 35.2, and 667 Bq kg ⁻¹ , respectively, all falling strictly within natural background levels. Considering the potential radiological hazards, various hazard indices were calculated, and the results indicated that all indices are within normal limits. Furthermore, statistical analyses were performed on the measured data to comprehensively evaluate the distribution patterns of radionuclides and the interrelationships among radiological parameters.