The highly mineralised formation waters in the coal mines of Poland’s Upper Silesian Coal Basin contain natural radioactive nuclides, mostly radium. The 226Ra concentration in the groundwater that flows into the underground mine workings reaches 390 Bq/L, and is sometimes exceeded by the 228Ra concentration. The radium-bearing water sometimes also contain barium ions, which enables coprecipitation of barium-radium sulphate. Another type of radium-bearing water contains sulphate ions instead of barium; in this case, radium is transported to settling ponds and downstream. We have assessed the daily activity of radium in waters flowing into the underground mines and being discharged to the environment. Based on 1995 data, we estimate that the total activity of radium isotopes flowing into the mines was about 1300 MBq/day, while the radium activity in the discharge waters was about 700 MBq/day. A similar assessment performed with 2016 data indicated that the total activity in inflows was roughly 1150 MBq/day, while that discharged to surface waters was about 450 MBq/day.
27 October 2016 in Journal of Radioanalytical and Nuclear Chemistry
The presence of radionuclides in environmental media, including sediment, is critical in assessing potential health risks due to external gamma radiation. This study investigates the spatial distribution of natural (Ra-226, Th-232, K-40) and artificial (Cs-137) radionuclides in sediment along the Dixcove coastline, Ghana, using High-Purity Germanium (HPGe) gamma-ray spectroscopy. The activity concentrations of Ra-226 ranged from ~14 to ~23 Bq/kg, Th-232 from ~3 to ~10 Bq/kg, and K-40 from ~44 to ~93 Bq/kg, with Cs-137 levels between 0.2 and 1.3 Bq/kg. The highest concentrations of Ra-226 and K-40 were found On-shore, suggesting terrestrial influence, while Th-232 displayed a more uniform distribution. Radiological risk assessments, including radium equivalent activity (Raeq), annual effective dose (AED), and gamma index (Iγ), confirmed that all measured values were below international safety thresholds, indicating no significant health risk. However, the variability in Cs-137 distribution suggests the need for continued monitoring to assess potential long-term contamination trends. A significant discrepancy was observed when comparing Cs-137 values from this study (maximum 1.3 Bq/kg) with previously reported data (~110 Bq/kg), raising concerns about methodological differences or environmental changes, which require further investigation. To address the observed discrepancies between this study and previous investigations, future research should incorporate in situ measurement techniques for a more comprehensive assessment of Cs-137 distribution.
30 September 2024 in Separation and Purification Technology