Measuring and modelling temporal trends of 226Ra in waters of a Spanish estuary affected by the phosphate industry

The presence and temporal evolution (1990–2001) of 226Ra in a tidal estuary affected by the phosphate industry has been investigated. Water samples collected in the course of four sep arate sampling campaigns were analysed for 226Ra content using a gas flow proportional coun ter following Ba copreci...

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Detalles Bibliográficos
Autor: Periáñez Rodríguez, Raúl
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/135241
Acceso en línea:https://hdl.handle.net/11441/135241
https://doi.org/10.1016/j.marenvres.2004.08.003
Access Level:acceso abierto
Palabra clave:Radium
Odiel-Tinto estuary
Phosphogypsum
Numerical modelling
Hydrodynamics
Sediment
Descripción
Sumario:The presence and temporal evolution (1990–2001) of 226Ra in a tidal estuary affected by the phosphate industry has been investigated. Water samples collected in the course of four sep arate sampling campaigns were analysed for 226Ra content using a gas flow proportional coun ter following Ba coprecipitation. Two 226Ra sources have been identified: direct discharges from the industrial complex and run-off from a phosphogypsum pile. Although activity levels are similar, or even higher, than those found in other environments affected by the phosphate industry, there has been a general decrease in contamination since direct discharges ceased in 1998 due to new regulations from the EU. However, sediments are now acting as a source of Ra to the water column due to redissolution processes. A numerical model of the estuary has been developed to describe quantitatively the experimental results. The model solves the hydrodynamics and the dispersion equation of 226Ra including interactions with sediments. Model results are, in general, in good agreement with observations