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

Diverse Monitoring Approaches Reveal 14C Dispersion Pattern and Its Impact on the Environment around the Tokai Reprocessing Plant

“…The characteristic of the dispersion is probably related not only to the meteorology but also to the topography of our site; the relatively flat terrain around the TRP may not allow the 14 C plume to stay, and thereby not allow the accumulation of greater activities of 14 C by vegetation as seen in a hilly terrain. 9) With respect to the northwest direction from the TRP, however, an inconsistency was found between the measurements for the Japanese mugwort samples and the calculations for the atmospheric CO 2 (compare Fig. 8 with Fig.…”

“…It is well documented that 14 C is released into the atmosphere by nuclear power plants during their routine operations, 5) and there are actually many publications reporting enhanced 14 C concentrations in the vicinity of nuclear power plants around the world. 7,9,11) In Japan, Momoshima et al 27) reported that the 14 C concentration in vegetation samples collected near a nuclear power plant (BWR) was on average about 20 Bq kg-C À1 higher than that collected far from the plant. In this study, two samples of rice grains that were taken from areas relatively close to nuclear power plants showed a slight excess of 14 C above the average (Fig.…”

“…A substantial number of recent publications tell us of the growing concern about 14 C releases from nuclear facilities and their impacts on the environment and the public, particularly in the vicinity of the facilities. [6][7][8][9][10][11] Carbon-14 is produced in nuclear reactors by the neutron reaction of stable isotopes of carbon, nitrogen, and oxygen in coolant, fuel, and structural materials. 12) Some of the 14 C atoms formed in the coolant are released into the atmosphere during normal operations of the reactors at the power plant sites, whereas 14 C produced in the fuel is released at fuel reprocessing plant sites when the fuel is reprocessed.…”

Radiocarbon Data from the Vicinity of Four South Korean Nuclear Power Plants in 2013–2014

“…Additionally, our collection of all samples was taken in the "impact zone" (less than 3 km from the NPP) compared with previous studies and not in the "perimeter zone" (>5 km), with specific activities close to the background values and the distance between the impact and perimeter zones. Accordingly, it seems that the Δ 14 C values of around 3 km from the Wolsong and Hanul NPPs (which show higher pMC values than Kori and Hanbit) in Figure 4 do not come close to the 14 C background value (32.5‰) or decrease below the value (Dias et al 2008). As a second trial for AMS 14 C measurement, we will collect more samples and perform more AMS measurements for the two NPPs (Wolsong and Hanbit).…”

“…While the silver grass samples show higher activity than those of tree leaf mostly at Wolsong, those from other NPPs show the opposite tendency (the samples of tree leaf show higher 14 C activity). The conversion of pMC into Bq/kg C is simply calculated in the relation of 100 pMC = 226 Bq/Kg C (Dias et al 2008). Table 2 compares our results (for as long as we could find them) related to 14 C around the NPPs with those of the previously published papers.…”