Geospatial Mapping of Background Ionizing Radiation in an Operational Quarry in Modakeke, Osun State, Nigeria.

Abstract

This study investigates the levels of background ionizing radiation in and around a quarry, focusing on geospatial radiation mapping to highlight “hotspots” within the quarry site. Using a portable FNIRSI GC-01 Geiger counter, ambient radiation dose rates were measured at 30 sampling points within the quarry. The results revealed that annual effective dose rates (AEDR), ranged from 1.23 mSv/year to 3.68 mSv/year, with 40% of the sampling points exceeding 2.5 mSv/year. Geospatial analysis identified distinct hotspots, particularly in the North-Eastern and central regions of the quarry. Compared to the global average of 2.4 mSv/year, approximately 43% of the sampling points exhibited elevated radiation levels, raising concerns about occupational exposure for quarry workers. The findings underscore the importance of regular monitoring and targeted mitigation strategies, such as zoning high-risk areas and implementing rotational work schedules, to minimize health risks. This study highlights the utility of geospatial radiation mapping in quarries to safeguard occupational health.