C-14, delta C-13 and total C content in soils around a Brazilian PWR nuclear power plant

• Nuclear power plants release C-14 during routine operation mainly as airborne gaseous effluents. Because of the long half-life (5730 years) and biological importance of this radionuclide (it is incorporated in plant tissue by photosynthesis), several countries have monitoring programs in order to quantify and control these emissions. This paper compares the activity of C-14 in soils taken within I km from a Brazilian nuclear power plant with soils taken within a reference area located 50 km away from the reactor site. Analyses of total carbon, delta C-13 and Cs-137 were also performed in order to understand the local soil dynamics. Except for one of the profiles, the isotopic composition of soil organic carbon reflected the actual forest vegetation present in both areas. The Cs-137 data show that the soils from the base of hills are probably allocthonous. The C-14 Measurements showed that there is no accumulation due to the operation of the nuclear facility, although excess C-14 Was found in the litter taken in the area close to power plant. This indicates that the anthropogenic signal observed in the litter fall has not been transferred yet to the soil. This study is part of an extensive research programme in which other samples including air, vegetation and gaseous effluents (taken in the vent stack of the Brazilian nuclear power reactors Angra I and II) were also analyzed. The present paper aimed to evaluate how C-14 emissions from the nuclear power plant are transferred and stored by soils present in the Surroundings of the reactor site. This is the first study concerning anthropogenic 14C in soils in Brazil. (9) 2009 Elsevier Ltd. All rights reserved.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

Keyword

Nuclear power plants

Cs137

C-13

Soils

C-14

PWR

Publication and Content Type

art (subject category)

ref (subject category)