Radiocarbon and Tritium Levels Along the Romanian Lower Danube River

Abstract

ABSTRACT. The Lower Danube Basin covers the Romanian-Bulgarian sub-basin downstream from Cazane Gorge and the sub-basins of the Siret and Prut rivers. To extensively survey the Romanian nuclear power plant impact on the Danube water, tritium and radiocarbon baseline values are required. Therefore, the reported study tried to establish these values based on a 2-yr sampling campaign covering 975 km of the Danube from Cazane Gorge to Tulcea. The tributaries Cerna, Jiu, Olt, and Arges were also included in this study. During the sampling campaigns, tritium concentration of different sampling locations showed values between 7 ± 2.1 and 33.5 ± 2.3 TU. Measured 14 C activity for the same locations ranged between 88.45 ± 1.46 and 112.36 ± 1.56 pMC. Lower values were recorded for tributaries: between 8.3 ± 2.1 and 12.2 ± 2.2 TU for tritium and between 67.3 ± 1.29 and 86.04 ± 1.42 pMC for 14 C. Despite the nuclear activity in the observed areas, tritium and 14 C activities presented slightly higher values for specific locations without any influence on Danube River water. INTRODUCTIONRivers are important freshwater sources, and much of the world's population has relied on rivers for its development. In recent years, many international and national hydrology research programs have focused on large river basins. In humid basins, precipitation processes are the primary signal traced by river discharge. Evidence that precipitation input signals are not static is found from long-term isotope records of European rivers. Interannual variations of these processes reflect the inherent decadal variability of precipitation processes. Comparing tritium levels in the Danube River with tritium levels in precipitation at Vienna (Rank et al. 1998) reveals that not only short-term signals but also long-term changes in the isotope ratio of precipitation are transmitted through the catchments and can be detected in river water. A comparison of measured and modeled 3 H contents in the Danube River revealed that the best fit that could be obtained (mean residence time of 3 yr) is still not satisfactory (Rank et al. 2005).The Danube River Basin is the second largest river basin in Europe, covering 801,463 km 2 (ICPDR 2005). It lies west of the Black Sea in central and southeastern Europe. Due to its geological and geographical conditions, the Danube River Basin can be divided into 3 main parts: the Upper, Middle, and Lower Danube Basin. About 65% of the Lower Danube Basin forms the natural border between Romania and Bulgaria. Two important nuclear power plants (NPP) for both countries are found in this region: Kozloduy NPP and Cernavoda NPP. Both countries consider nuclear energy to be a potential energy solution for future economic development. In fact, nuclear power generates between 10% and 45% of the electricity for the Danube riparian countries. Therefore, Romania has already built a new CANDU (CANada Deuterium Uranium)-type unit in Cernavoda, which was put into operation in 2007, and Bulgaria started negotiations for a new NPP in Belene...

Isotopic fingerprint of the middle Olt River basin, Romania

“…There are several studies published on isotopic investigations of Romanian rivers [8][9][10][11][12], some with emphasis on the use of tritium as a tracer in the environment [13,14], but only few regarding the Olt River [15]. In this paper we focused on the middle watershed of the Olt River (Romania), a Danube tributary, presenting the results of isotopic investigations conducted during seasonal campaigns between November 2010 and August 2011.…”

Reconstruction and Optimization of Tritium Time Series in Precipitation of Beijing, China

“…Tritium ( 3 H) has been used in earth and environmental sciences for several decades (Leboucher et al 2004;Varlam et al 2010;Zhai et al 2011), especially in groundwater studies to calculate the recharge rate and to identify the presence of modern recharge (Liu 1995;Noakes et al 1998;Celle et al 2001;Avrahamov et al 2010). Since Kaufman and Libby (1954) first proposed that tritium could be utilized for groundwater dating, it has been applied in many regions of the world (e.g.…”