Carbon-14 content in surface soils near atmospheric and below ground nuclear detonations. (November 2019)

• Record Type: Journal Article
• Authors: Snow, Mathew S.; Ward, Jessica; Olson, John; Bucher, Brian; Delmore, James; Adamic, Mary; Watrous, Matthew; Snyder, Darin
• Is Part Of: Journal of environmental radioactivity. Volume 208/209(2019)
• Publication Date: 2019-11
• Subjects: Carbon-14 -- Elemental carbon -- Organic carbon -- Nuclear weapons testing; 14C carbon-14 -- 137Cs cesium-137 -- 152Eu europium-152 -- 60Co cobalt-60 -- NNSS Nevada National Security Site -- INL Idaho National Laboratory -- AMS Accelerator Mass Spectrometry; Radioactivity -- Periodicals; Radiation, Background -- Periodicals; Radioecology -- Periodicals; Radioactive pollution -- Periodicals; Environmental Pollutants -- Periodicals; Radioactive Pollutants -- Periodicals; Radioactivity -- Periodicals; Radioécologie -- Périodiques; Pollution radioactive -- Périodiques; Fond de rayonnement -- Périodiques; 539.752
• DOI: 10.1016/j.jenvrad.2019.106007
• Languages: English
• ISSNs: 0265-931X

Abstract

Abstract: Global and regional releases of 14 C have resulted from nuclear weapons testing activities; assessment of the chemical behavior and mechanisms of environmental transport and deposition of this radionuclide can assist remediation strategy development efforts and provide insights into global carbon cycling processes. This work reports a systematic evaluation of 14 C in surface soils taken from the Nevada National Security Site. Surface soil samples are derived from above- and underground test locations, with underground test sites representing a range from near complete containment to uncontrolled radioactive releases. Only one surface soil taken from a underground test location (i.e. the Baneberry shot) shows elevated 14 C concentrations (319 ± 9 pMC) in addition to elevated concentrations of 137 Cs, 60 Co and 152 Eu above regional backgrounds. Surface soils from above-ground test locations show extremely high 14 C content (~1000 to 10, 000 pMC); elevated concentrations of 152 Eu and 60 Co for these soils are also observed, with 137 Cs at or below background levels. Taken together, these data suggest that 14 C in surface soils from above-ground tests is primarily derived from in-situ neutron activation of the native soil material, whereas 14 C in surface soils from underground tests may be from either recondensed particulate material or soil activation. Highlights: Carbon-14 from nuclear tests in surface soils at NNSS reported. Only one subsurface test shows elevated C-14 (319 ± 9 pMC). Above ground tests show very high C-14 (~1000–10, 000 pMC). C-14 correlated with elevated Eu-152 and Co-60, not correlated with Cs-137. Data suggests C-14 primarily derived from in-situ neutron activated soil.