Radionuclides transfer between water and atmosphere in the Loire estuary (FLORE project)

Abstract

Abstract. In estuaries, volatiles radionucleides ( 14 C, 3 H, 131 I) originating from anthropogenic liquid waste release from nuclear reactor or hospitals are potentially transferable to the atmosphere. Due to the high biologic activity, the degradation of organic matter produce carbon dioxide fluxes to the atmosphere allowing transfer of 14 CO 2 released by nuclear industry. Similarly tritium is transfered to the atmosphere trough evaporation process. We present here, results obtained during FLORE-1 cruise in February 2003, a winter period when biological activity is supposed to be low. The first results of iodine 131 distribution and estimations of radiocarbon and tritium fluxes are presented.

Water to atmosphere fluxes of 131I in relation with alkyl-iodide compounds from the Seine Estuary (France)

“…On the Loire, another French river, activities varying between 0.8 and 2.0 Bq m À3 were recorded for salinity of 0 psu, i.e. lower and less variable activities values than those observed in this work (Fontugne et al, 2005). Furthermore, on the Loire, upstream of the site where measurements were taken, are implanted 14 nuclear reactors compared with only 2 on the Seine river which, combined with the fact that the catchments population and industrial activities are denser on the Seine than on the Loire, strengthens the idea that the higher 131 I activities measured in this work are more linked to non-nuclear human activities, probably of medical origin.…”

Temporal and Spatial Variations of Freshwater Reservoir Ages in the Loire River Watershed

“…The samples used in this study were strictly selected during nonrelease periods. In previous studies, no memory effect was observed after a release (Fontugne et al 2007).…”

“…River discharge, chlorophyll- a concentration, alkalinity, DIC concentration, DIC δ 13 C, 14 C activity, and reservoir age are reported in Table 2. Unpublished values obtained during the 2004 and 2005 LORA experiments (Fontugne et al 2007) are also reported in italics in Table 2. Some reservoir age values are missing because sampling sites were under the influence of a nuclear power plant release or because the measurement failed.…”

“…Sampling year and month are specified after the location name. Unpublished values obtained during the 2004 and 2005 LORA experiments (Fontugne et al 2007) are reported in italic (nd=not determined).…”

“…All sites were sampled during these campaigns, except V2 (upstream Civaux) that was sampled only in July and October 2013 and upstream sites of the Loire and tributaries (L1, A1, Ma1, S1, and Lo1) that were sampled in March 2014. We also used unpublished data from three other campaigns conducted in September 2004, May 2005, and November 2005 in which the sampling sites were located in the middle Loire River and the samples were collected on the riverbank (Fontugne et al 2007; Marang et al 2011).…”