Distribution and storage of uranium, and its decay products, in floodplain sediments. (1st May 2023)

• Record Type: Journal Article
• Authors: Millward, Geoffrey E.; Blake, William H.
• Is Part Of: Environmental pollution. Volume 324(2023)
• Publication Date: 2023-05-01
• Subjects: Uranium -- Radionuclides -- Floodplains -- Storage -- Abandoned uranium mines -- Europe; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2023.121356
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Industrialised rivers contain legacy contaminants stored in their sediments and floodplain soils which may inhibit attainment of environmental quality criteria. The River Fal catchment, SW England, is impacted by inputs from uranium mining and clay production and serves as an exemplar for understanding the consequences of medium-term process dynamics in contaminated basins. Radionuclides were determined, by gamma spectroscopy, in six cores from the river floodplain with the aim of quantifying the activities of 238 U, and its decay products, and the bomb fallout radionuclides 137 Cs and 241 Am. Activity concentrations of 238 U implied inputs from mining, accentuated by flood events and historic industrial accidents, whereas 210 Pb activities included a significant input of unsupported 210 Pb linked to processed mine spoil. The radionuclide inventories did not decrease systematically downstream revealing evidence of attenuation of particulate radionuclides within the river floodplain sediment column. Storage of legacy contaminants in fluvial systems, at levels in excess of contemporary environmental quality guidelines, emphasises the challenges posed by changing climatic conditions. This scenario raises significant consequences for the management of uranium-contaminated, fertile riverine floodplains within Europe. Graphical abstract: Image 1 Highlights: An abandoned uranium mine on the River Fal (UK) is a source of legacy radionuclides. High activities of 238 U and its decay products are distributed within the river basin. Floodplains were identified as important depositional zones for uranium pollution. Similar pollution scenarios arising from redundant uranium mines exist in Europe.