Isotopes of polonium (²¹⁰Po) and uranium (²³⁴U and ²³⁸U) in the industrialised area of Wiślinka (North Poland)

Abstract

Phosphogypsum is very much enriched in natural polonium ²¹⁰Po, while the uranium radionuclides (²³⁴U and ²³⁸U) tend to be in waters around waste dumps. The migration and distribution of uranium and polonium radionuclides in analysed water samples are not uniform. The amounts of uranium isotopes in a retention reservoir around the waste dump are 100 times higher than in typical natural river waters. The concentration of uranium in surface water samples collected near Wiślinka (North Poland) ranged widely between 0.05 ± 0.02 and 430 ± 5 µg L^–1. In phosphogypsum samples, uranium concentrations varied in the range of 4.03 ± 0.08 and 0.65 ± 0.05 mg kg^–1 in samples collected in 1997 and 2007, respectively. We observed that the activity ratio ²³⁴U/²³⁸U is approximately about one in the phosphogypsum (0.90 ± 0.06 and 0.97 ± 0.03) and in the water of the immediate surroundings of waste heap (1.00 ± 0.06 and 1.07 ± 0.05), while in surface river water from Martwa Wisła River is higher than one (1.10 ± 0.07 and 1.16 ± 0.13). The phosphogypsum samples contain much higher ²¹⁰Po activity in comparison with uranium radionuclides. The concentration of ²¹⁰Po in phosphogypsum samples is similar or slightly higher in 1997 and 2007 (600 ± 10 and 700 ± 10 Bq kg^–1, respectively). Finally, the principal sources of ²¹⁰Po, ²³⁴U, ²³⁸U radionuclides in the Wiślinka area waste dump are phosphorites and phosphogypsum, produced by Phosphoric Fertilisers Industry of Gdańsk.

Keywords:

• polonium ²¹⁰Po
• uranium ²³⁴U and ²³⁸U
• concentration
• phosphogypsum
• surface water
• industrialised areas
• Wiślinka (Poland)

Acknowledgements

The authors would like to thank the Polish Ministry of Higher Education and Sciences of the financial support of this work under grant: DS-8210-4-0086-8 and BW/8000-5-0109-8. We wish to thank particularly Bogusław Plewczyński for his assistance in sampling research material.