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14C Measurements at PWR-Type Nuclear Power Plants in Three Middle European Countries

Published online by Cambridge University Press:  18 July 2016

György Uchrin ,
Ede Hertelendi ,
Gábor Volent ,
Ondrej Slavik ,
Jozef Morávek ,
Ivan Kobal  and
Barbara Vokal
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Abstract

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Regular 14C sampling of discharged air began in 1988 at Paks Nuclear Power Plant (NPP), Hungary, and in 1991 at NPPs in Krsko, Slovenia and Bohunice, Slovakia. Monitoring of 14C discharges is carried out at all NPPs with similar differential samplers continuously collecting 14C in the form of 14CO2 and 14CnHm. The main results of airborne discharge monitoring are as follows: 14C activity concentration varied roughly within a factor of two around their mean values, 125 Bq m-3 and 90 Bq m-3 for Paks and for Krsko NPP, respectively. The pattern of discharge for Bohunice NPP is slightly different from that at the other two stations. At Bohunice, there has been a continuous increase in the discharge rate at power unit V1, starting with 70 Bq m-3 in 1991 and reaching a value of 190 Bq m-3 in 1995. The values for power unit V2 are 50 Bq m-3 and 82 Bq m-3. The average normalized yearly discharge rates are 0.887 (TBqGWe-1yr-1) for Paks, 0.815 (V1) and 0.500 (V2) for Bohunice, and 0.219 for Krsko. Most of the discharged 14C is in hydrocarbon form, 95% for Paks and Bohunice V2, but the CO2 fraction may reach 25% or 43% at Bohunice V1 and Krsko, respectively. At Bohunice V1, not only the discharge rate increased but the 14CO2 ratio to the total changed from 30% to 13%. The local radiological impact is estimated to be 1.5 μSv a-1 for Paks, 1.7 μSv a-1 for Bohunice, and 0.12 μSv a-1 for Krsko. The 14C excess in the environment has been measured at Paks NPP since 1989. Based on the monitoring data, the long-term average 14C excess from the Paks NPP was D14C=50% for hydrocarbons. Tree-ring analysis has shown a slight excess around Krsko NPP: D14C is equal to 199.9% for a tree at 1 km from the NPP compared with a “reference” one for which D14C was equal to 111.6% (in 1994).

Type
Part 1: Methods
Information
Radiocarbon , Volume 40 , Issue 1: 16th International Radiocarbon Conference 16-20,1997 Groningen , 1997 , pp. 439 - 446
Copyright
Copyright © The American Journal of Science 

References

Hertelendi, E., Csongor, É., Záborszky, L., Molnár, J., Gál, J., Györffy, M. and Nagy, S. 1989 A counter system for high-precision 14C dating. In Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 399–406.CrossRefGoogle Scholar
Hertelendi, E., Uchrin, Gy. and Ormai, P. 1989 14C release in various chemical forms with gaseous effluents from the Paks Nuclear Power Plant. In Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 754–761.CrossRefGoogle Scholar
Khalil, M. A. K. and Rasmussen, R. A. 1985 Causes of increasing methane: Depletion of hydroxyl radicals and rise of emissions. Atmospheric Environment 19: 397–407.Google Scholar
Kunz, C. 1985 Carbon-14 discharge at three light-water reactors. Health Physics 49(1): 25–35.Google Scholar
Levin, I. and Kromer, B. 1997 Twenty years of high-precision atmospheric 14CO2 observations at Schauinsland station, Germany. Radiocarbon 39(2): 205–218.CrossRefGoogle Scholar
Levin, I., Kromer, B., Barabas, M. and Münnich, K. O. 1988 Environmental distribution and long-term dispersion of reactor 14CO2 around two German nuclear power plants. Health Physics 54: 149–156.CrossRefGoogle ScholarPubMed
Loosli, H. H. and Oeschger, H. 1989 14C in the environment of Swiss nuclear installations. In Long, A., Kra, R.S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 747–753.Google Scholar
McCartney, M., Baxter, M. S. and Scott, E. M. 1988a Carbon-14 discharges from the nuclear fuel cycle: 1. Global Effects. Journal of Environmental Radioactivity 8: 143–155.CrossRefGoogle Scholar
McCartney, M., Baxter, M. S. and Scott, E. M. 1988b Carbon-14 discharges from the nuclear fuel cycle: 2. Local Effects. Journal of Environmental Radioactivity 8: 157–171.CrossRefGoogle Scholar
Milton, G. M., Kramer, S. J., Brown, R. M., Repta, C. J. W., King, K. J. and Rao, R. R. 1995 Radiocarbon dispersion around Canadian nuclear facilities. In Cook, G. T., Harkness, D. D., Miller, B. F. and Scott, E. M. eds., Proceedings of the 15th International 14C Conference. Radiocarbon 37(2): 485–496.CrossRefGoogle Scholar
National Council on Radiation Protection (NCRP) 1985 Carbon-14 in the Environment, Recommendations of the National Council on Radiation Protection and Measurements. NCRP Report No. 81. Bethesda, National Council on Radiation Protection and Measurement: 91 p.Google Scholar
Otlet, R. L., Longley, H. and Walker, A. J. 1989 Measurements of carbon-14 in tree rings from trees growing in the Sellafield area. Part 13, Studies of Environmental Radioactivity in Cumbria AERE-R 12362.Google Scholar
Otlet, R. L., Walker, A. J. and Fulker, M. J. 1990 Survey of the dispersion of 14C in vicinity of the UK reprocessing site at Sellafield. Radiocarbon 32(1): 23–30.Google Scholar
Otlet, R. L., Walker, A. J. Fulker, M. J. and Collins, C. 1997 Background carbon-14 levels in UK Foodstuffs, 1981–1995, based upon a 1992 Survey. Journal Environmental Radioactivity 34: 91–101.Google Scholar
Stenström, K., Erlandsson, B., Hellborg, R., Skog, G. and Wiebert, A. 1995 14CO2 and total airborne 14C releases from PWR and a BWER at Ringhals Nuclear Power Plant measured with accelerator mass spectrometry. Report for project SSIP 781.93, Lund, Sweden: 8 p.Google Scholar
Uchrin, G., Csaba, E., Hertelendi, E., Ormai, P. and Barnabás, I. 1992 14C release from a Soviet-designed pressurized water reactor nuclear power plant. Health Physics 63: 651–655.CrossRefGoogle ScholarPubMed
Uchrin, G. and Hertelendi, E. 1992 Development of a reliable differential carbon-14 sampler for environmental air and NPP stack monitoring. Final Report of OMFB contract No. 00193/1991 (in Hungarian).Google Scholar
United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 1993 Sources and Effects of Ionizing Radiation. 1993 Report to the General Assembly. New York, United Nations: 922 p.Google Scholar