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Plutonio derivado de Hanford en los sedimentos del río Columbia
Science (New York, N.Y.)
|November 20, 1981
Resumen
Los sedimentos del río Columbia contienen plutonio con proporciones de isótopos que indican tanto la lluvia global como una fuente local. El plutonio-239 de los reactores nucleares de Hanford contribuye significativamente a la contaminación de los sedimentos.
Área de la Ciencia:
- Ciencias ambientales Ciencias ambientales.
- Química Nuclear La Química Nuclear es el campo de la química nuclear.
- Evaluación radiológica Evaluación radiológica.
Sus antecedentes:
- Los sedimentos del río Columbia son un sumidero para los contaminantes ambientales.
- Los isótopos de plutonio se originan tanto en las lluvias globales como en las actividades nucleares locales.
- Comprender las fuentes de plutonio es crucial para la remediación ambiental y la evaluación de riesgos.
Objetivo del estudio:
- Para investigar las fuentes de isótopos de plutonio en los sedimentos del río Columbia.
- Cuantificar la contribución de las operaciones históricas de los reactores nucleares a la contaminación por plutonio.
- Para diferenciar entre la lluvia global y las fuentes locales de plutonio en el medio ambiente fluvial.
Principales métodos:
- Análisis espectrométrico de masas de los isótopos de plutonio (Pu-240, Pu-242, Pu-239) en muestras de sedimentos.
- Comparación de las relaciones isotópicas medidas con los valores de lluvia radiactiva global conocidos.
- Modelado para estimar la contribución del plutonio derivado de los reactores.
Principales resultados:
- Las proporciones de plutonio-240 a plutonio-242 se alinean con los patrones de lluvia global.
- Las proporciones de plutonio-240 a plutonio-239 se desvían significativamente de la lluvia global, lo que indica una fuente adicional.
- Se estima que entre el 20 y el 25 por ciento del plutonio en los sedimentos del embalse de McNary proviene de las operaciones del reactor de Hanford.
Conclusiones:
- Los sedimentos del río Columbia muestran una firma mixta de plutonio de la lluvia global y los reactores del sitio de Hanford.
- El agua de efluente del reactor de Hanford contribuyó con el neptunio-239, que se descompuso en plutonio-239, contaminando los sedimentos.
- Las actividades nucleares locales representan una fuente significativa y cuantificable de contaminación por plutonio en los sedimentos aguas abajo.
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