Ecological Chronology of Nuclear Fuel Cycle Sites

Abstract

We compared 14C levels in annual growth rings of pine trees around the Tomsk nuclear fuel reprocessing plant (NFRP) and the Chernobyl nuclear power plant (NPP). At the Chernobyl site, samples were taken from the control area (within a 30-km radius zone around the site) to a distance of 80 km. In Tomsk, we collected samples between 8–10 km and 10–15 km from the site, taking into account prevailing wind directions. Background samples were collected 200 km from the plant. Samples were converted to benzene and counted in an ultra-low-level LSC Quantulus 1220™. Because of the Chernobyl accident, a signal can be detected in the background of routine plant operation. Comparison with the Tomsk data suggests that the routine discharges from Tomsk are more significant than the discharge from the Chernobyl accident. We estimated Tomsk NFRP annual discharge level at up to 30–45 TBq 14C from 1985 to 1988.

Radiocarbon Releases from the 2011 Fukushima Nuclear Accident

“…Similarly, the 14 C concentration in the early wood from Takase is about 2 times higher than that in the late wood. Such a pattern has been observed in the 1986 rings collected from three sites within 2–12 km of the Chernobyl nuclear power plant, as a result of the accident that occurred on the 26 th April 19864.…”

“…However, the Chernobyl NPP accident resulted in a maximum 14 C excess of 281.6 Bq kg −1 C within the local environment, while the affected area, with a 14 C excess of >10 Bq kg −1 C, extended to >40 km from the plant45. Therefore, in comparison with the Chernobyl accident, releasing a 14 C activity of 44 PBq5, the observed Fukushima-derived 14 C release was very likely significantly smaller.…”

“…Elevated 14 C activities have been reported around many nuclear reactor sites worldwide during normal operations3. As an example of a nuclear accident, the Chernobyl NPP accident resulted in a maximum 14 C excess of 281.6 Bq kg −1 C within the local environment, while the affected area, with a 14 C excess of >10 Bq kg −1 C, extended to >40 km from the plant45. Accordingly, the release of 14 C from the Chernobyl accident was estimated to be 44 PBq5.…”

Local variance of atmospheric 14C concentrations around Fukushima Dai-ichi Nuclear Power Plant from 2010 to 2012

“…Atmospheric 14 C activity has been enhanced by the nuclear weapon tests in the 1950s and 1960s, discharges associated with the nuclear fuel cycle and nuclear accidents, and diluted by 14 C-free fossil fuel combustion from biosphere [ 9 , 10 ]. To study how these factors influence the atmospheric 14 C activity, tree rings are considered an ideal sample type because of their rapid response to atmospheric 14 C variability [ 11 – 13 ].…”

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

“…Considering that 14 C specific activities of plants may vary according to the atmospheric 14 C: 12 C ratio, many studies have investigated atmospheric 14 C activities in the vicinity of nuclear power plants using vegetation as bioindicators (Obelic et al, 1986;Levin et al, 1988;Loosli and Oeschger, 1989;Buzinny et al, 1995;Milton et al, 1995;Stenström et al, 1996b;Buzinny et al, 1998;Milton and Kramer, 1998;Stenström et al, 1998;Mikhajlov et al, 1999;Magnusson et al, 2004).…”