Side Scan Sonar Survey of Clinch River and Poplar Creek, Tennessee

Abstract : During the 1950s, quantities of chemical materials were released into local waterways in association with nuclear energy research and weapons components production at the Oak Ridge National Laboratory (ORNL). Plans and specifications for studying the distribution and extent of any contamination are presently being prepared by ORNL. The objective of this study is to delineate the characteristics and features of the river bottom topography and sediments along Clinch River and Poplar Creek, Tennessee. A side scan sonar investigation was performed to provide insight into the general sediment characteristics and to highlight the distribution, extent, and continuity of fine-grain (clayey) sediment deposits. Sediments of this type are found almost exclusively on the bottom of Clinch River between river miles 0.0 and 44. The percentages of silt and clay sediments, as determined from bottom samples, are greater than 70 percent and have average density values ranging from 1.15 to 1.40 g/cu cm. Along the remainder of the Clinch River project area, less extensive deposits of fine-grained material are found. The results supplement previously obtained soil samples and better identify sites best suited for additional sediment coring. The side scan sonar was also able to detect and clearly define river bottom geologic and cultural features along the length of the project area.