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The inflow of 234U and 238U from the River Odra drainage basin to the Baltic Sea

Skwarzec B., Tuszkowska A., Boryło A.

Oceanologia

2010

No. 52 (4)

705-725

In this study the activity of uranium isotopes 234U and 238U in Odra river water samples, collected from October 2003 to July 2004, was measured using alpha spectrometry. The uranium concentrations were different in each of the seasons analysed; the lowest values were recorded in summer. In all seasons, uranium concentrations were the highest in Bystrzyca river waters (from 27.81 š 0.29Bq m-3 of 234U and 17.82 š 0.23 Bq m-3 of 238U in spring to 194.76 š 3.43 Bq m-3 of 234U and 134.88 š 2.85 Bq m-3 of 238U in summer). The lowest concentrations were noted in the Mała Panew (from 1.33 š 0.02 Bq m-3 of 234U and 1.06 š 0.02 Bq m-3 of 238U in spring to 3.52 š 0.05 Bq m-3 of 234U and 2.59š 0.04 Bq m-3 of 238U in autumn). The uranium radionuclides 234U and 238U in the water samples were not in radioactive equilibrium. The 234U / 238U activity ratios were the highest in Odra water samples collected at Głogów (1.84 in autumn), and the lowest in water from the Noteć (1.03 in winter and spring). The 234U / 238U activity ratio decreases along the main stream of the Odra, owing to changes in the salinity of the river's waters. Annually, 8.19 tons of uranium (126.29 G Bq of 234U and 100.80 G Bq of 238U) flow into the Szczecin Lagoon with Odra river waters.

Uranium isotopes in waters and bottom sediments of rivers and lakes in Poland

Pietrzak-Flis Z., Kamińska I., Chrzanowski E.

Nukleonika

2004

Vol. 49, nr 2

69-76

Activity concentrations of 238U, 234U and 235U were determined in waters and bottom sediments in two main rivers in Poland (the Vistula and Odra rivers) with their tributaries, in four coastal rivers and in six lakes. Concentrations of 238U and 234U were compared with the concentrations of 226Ra determined in another study. As compared with concentrations in coastal rivers and in lakes, enhanced concentrations of the radionuclides were observed in water and bottom sediments in the upper and middle courses of the Vistula river, whereas in the Odra river the enhanced concentrations were present only in the bottom sediments. The enhanced concentrations in the Vistula river result from the discharge of coal mine waters from the Upper Silesian Coal Basin, and they indicate that the discharge was continued. The enhanced concentrations in the Odra river observed only in bottom sediments indicate that the discharge occurred in the past. The 234U/238U ratio for the bottom sediments was close to unity, indicating that these isotopes were close to equilibrium, whereas for water the average ratio was from 1.2 for lakes to 1.5 for the Vistula river, demonstrating the lack of equilibrium.