Monitoring radionuclide and suspended-sediment transport in the Little Colorado River basin, Arizona and New Mexico, USA

John R. Gray; Gregory G. Fisk

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USGS · 70120617

Monitoring radionuclide and suspended-sediment transport in the Little Colorado River basin, Arizona and New Mexico, USA

John R. Gray·Gregory G. Fisk

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Abstract

From July 1988 through September 1991, radionuclide and suspended-sediment transport were monitored in ephemeral streams in the semiarid Little Colorado River basin of Arizona and New Mexico, USA, where in-stream gross-alpha plus gross-beta activities have exceeded Arizona's Maximum Allowable Limit through releases from natural weathering processes and from uranium-mining operations in the Church Rock Mining District, Grants Mineral Belt, New Mexico. Water samples were collected at a network of nine continuous-record streamgauges equipped with microprocessor-based satellite telemetry and automatic water-sampling systems, and six partial-record streamgauges equipped with passive water samplers. Analytical results from these samples were used to calculate transport of selected suspended and dissolved radionuclides in the uranium-238 and thorium-232 decay series.

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Source-reported bounding extent: 34.1038982° to 34.1093356° latitude; -109.3300314° to -109.3201134° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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John R. Gray, Gregory G. Fisk. 1992. Monitoring radionuclide and suspended-sediment transport in the Little Colorado River basin, Arizona and New Mexico, USA. https://pubs.usgs.gov/publication/70120617

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