Anthropogenic 236U and Pu at remote sites of the South Pacific

M B Froehlich; A Akber; S D McNeil; S G Tims; L K Fifield; A Wallner

doi:10.1016/j.jenvrad.2019.05.003

Anthropogenic ²³⁶U and Pu at remote sites of the South Pacific

J Environ Radioact. 2019 Sep:205-206:17-23. doi: 10.1016/j.jenvrad.2019.05.003. Epub 2019 May 10.

Authors

M B Froehlich¹, A Akber², S D McNeil², S G Tims², L K Fifield², A Wallner²

Affiliations

¹ Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia. Electronic address: [email protected].
² Department of Nuclear Physics, Australian National University, Canberra, ACT, 2601, Australia.

PMID: 31082674
DOI: 10.1016/j.jenvrad.2019.05.003

Abstract

Anthropogenic radionuclides, like ²³⁶U and ^239,240Pu, are present in the environment as a result of global fallout from nuclear weapons tests conducted in the 1950s and 1960s and can potentially be used as tracers in soil erosion and sediment movement studies. Here, we report data on ²³⁶U and ^239,240Pu in soil samples from the Motueka Valley (New Zealand) and for the first time from two remote islands Rarotonga and Atiu (Cook Islands) in the South Pacific. ²³⁶U and ^239,240Pu were measured using Accelerator Mass Spectrometry (AMS) at the Australian National University. The ²³⁶U and ²³⁹Pu isotope concentrations versus soil depth and the ²⁴⁰Pu/²³⁹Pu and ²³⁶U/²³⁹Pu isotope ratios are discussed for each site. The radionuclide depth dependence revealed any soil disturbance, whereas the isotopic signatures indicated the source of the radionuclides' origin.

Keywords: (236)U/(239)Pu; (240)Pu/(239)Pu; Accelerator mass spectrometry; Soil; South Pacific; Southern Hemisphere.

MeSH terms

Mass Spectrometry
New Zealand
Plutonium / analysis*
Polynesia
Radiation Monitoring*
Radioactive Fallout / analysis*
Soil Pollutants, Radioactive / analysis*
Uranium / analysis*

Substances

Radioactive Fallout
Soil Pollutants, Radioactive
Uranium-236
Uranium
Plutonium
Plutonium-239