Sediment Radioactivity in the Columbia River Estuary

Résumé du livre

Surface sediments of the Columbia River estuary contain more 51Cr and 65Zn than the river water flowing over them. Highest concentrations of radioactivity are found in fine sediments whose distribution is irregular and subject to variation with changing river flow. Columbia River radionuclides have been measured in sediments at a distance of 10 km from the mouth of one of its small tributaries, sometimes with higher radionuclide concentrations than the Columbia River sediments. Sediment radioactivity was measured with an in situ gamma-ray detector attached to a multichannel analyzer, making it possible to analyze many samples rapidly with a minimum disturbance to surface layers.