Pre-Operational Assessment of Natural Radioactivity and Radiological Hazards in Soils of a Prospective Mining Area in Lakki Marwat, Pakistan

Establishing a baseline data of environmental radioactivity in mineral-rich regions is essential for environmental protection and regulatory planning, particularly prior to the initiation of mining activities. This study presents a baseline assessment of natural and anthropogenic radionuclides in the soils of Lakki Marwat, a district with significant mineral potential in Khyber Pakhtunkhwa, Pakistan. A total of 35 soil samples were collected and analyzed using a high-purity germanium (HPGe) based gamma-ray spectrometry system. The mean activity concentrations of 226Ra (48 Bqkg−1), 232Th (48 Bqkg−1), and 40K (520 Bqkg−1) were found to exceed the global median values reported in UNSCEAR 2000. The generally low or non-detectable 137Cs activity indicates that its detectable fallout is not a major contributor to the measured radionuclide inventory. The mean values of occupancy‑weighted absorbed dose rate (125 nGy h−1), total AEDE (0.77 mSvy−1), and ELCR (2.95 × 10−3) exceeded the corresponding global average values of 79 nGyh−1, 0.50 mSv, and 1.50 × 10−3,respectively, suggesting potential radiological risks in the study area. Principal component analysis (PCA) results indicated that radionuclide distribution may be predominantly controlled by geogenic factors, with strong correlations between 226Ra and 232Th, while 40K exhibited partial independence due to possible mineralogical variability. The findings establish a reliable baseline dataset for the study area and highlight the importance of continuous radiological monitoring, particularly in view of anticipated mineral extraction activities. This study contributes to environmental risk assessment and supports sustainable resource management while ensuring public and occupational safety.