Environmental Distribution and Behavior of 3h and 14c Around Wolsong Nuclear Power Plants

Abstract

To estimate of the dispersion trend of 3H and 14C discharged from the Wolsung Nuclear Power Plants, the present level of 3H and 14C in environmental samples in the vicinity of the Wolsong site was studied. Tree-ring cellulose analyses were carried out for retrospective evaluation of 3H and 14C in the environment around the Wolsong Nuclear Power Plants. 3H released from the Wolsong Nuclear Power Plants has affected an area up to a 25-km radius from the site, while almost all 14C was deposited within a 2-km radius, reaching to a natural level over 2 km. Organically bound tritium concentrations in tree rings were strongly correlated with the gaseous tritium discharge rate, while delta14C (excess) in tree rings ranged from 204 per thousand to 460 per thousand, which did not significantly vary with year.

A follow up of the decrease of non exchangeable organically bound tritium levels in the surroundings of a nuclear research center

“…This experimental variation could be modelled consistently by an exponential decay of the NE-OBT activity with the distance (x) with A NEÀOBT ¼ Ce ðÀx=t1Þ þ B (with C ¼ 82.3 AE 4.8, t 1 ¼ 0.80 AE 0.09 and B ¼ 1.3 AE 0.6). This trend, where OBT activity decreased with increasing distance from the site, was also observed previously around Wolsong Nuclear power plant (Kim et al, 2000) for higher activities. Moreover, the activity ratios determined in this work, considering that measured at 1 km as a reference, are similar to those observed around Wolsong.…”

“…Those values are consistent with those determined on other site where tritium releases are occurring (Gautam et al, 2010;Kim et al, 2000;Patra et al, 2008). Based on tritium released activity data for 2006 the atmospheric dilution factor is also calculated using mean annual observed meteorological data and the code GASCON (Monfort et al, 2010).…”

14C content in vegetation in the vicinities of Brazilian nuclear power reactors

“…2). Analysis of these samples was intended to investigate how vegetation records atmospheric 14 C fluctuations, considering that 14 C emissions are not expected to be detected at distances greater than 4 km from power plants (Kim et al, 2000;Milton and Kramer, 1998;Magnusson et al, 2004;Levin et al, 1988). …”

14C Levels in Tree Rings Located Near Qinshan Nuclear Power Plant, China

“…Owing to their growth characteristics, tree rings are widely used to study the 14 C discharge of nuclear facilities. The -cellulose in tree rings remains fixed after formation, so tree rings can be used to indicate the average atmospheric 14 C activity during the growing season in different years (McNamara and McCartney 1998;Stenström et al 1998;Kim et al 2000;Isogai et al 2002). Thus, for monitoring 14 C discharges from the nuclear facilities in previous years, tree rings are an appropriate environmental indicator.…”