RESUMEN
Analyzing uranium isotopic and activity ratios can give valuable information for hydrologic and environmental studies such as insights to weathering processes, estimating water mixing ratios, and identifying water sources. The authors employed an inductively coupled plasma mass spectrometer (ICP-MS) to perform environmental level concentration measurements of isotopic uranium on 380 groundwater samples from various locations within the state of Idaho. The U:U uranium activity ratios (UAR) for these samples range between 0.91 and 6.21, which suggests that the parent U is not in equilibrium with its decay product U. The U:U isotopic ratio was also measured for each sample to confirm that there was no depleted or enriched uranium present. All 380 samples exhibited the natural isotopic ratios of U and U isotopes. Therefore, it was concluded that the U:U UARs reflect natural variations in the Idaho groundwater systems.
Asunto(s)
Agua Subterránea/análisis , Monitoreo de Radiación/métodos , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Calibración , Monitoreo del Ambiente/métodos , Idaho , Isótopos , Espectrometría de Masas , Modelos Teóricos , Análisis EspectralRESUMEN
The determination of uranium concentrations in natural water samples is of great interest due to the environmental consequences of this radionuclide. In this study, 380 groundwater samples from various locations within the state of Idaho were analyzed using two different techniques. The first method was Kinetic Phosphorescence Analysis (KPA), which gives the total uranium concentrations in water samples. The second analysis method was inductively coupled plasma mass spectrometry (ICP- MS). This method determines the total uranium concentration as well as the separate isotope concentrations of uranium. The U/U isotopic ratio was also measured for each sample to confirm that there was no depleted or enriched uranium present. The results were compared and mapped separately from each other. The study also found that in some areas of the state, natural uranium concentrations are relatively high.