ORNL/TM-9791

Oak Ridge National Laboratory

Environmental Sciences Division

Sediment Contamination in Streams Surrounding the Oak Ridge Gaseous Diffusion Plant

T. L. Ashwood, C. R. Olsen, I. L. Larsen, P. D. Lowry

Date Issued--May 1986

Prepared for the Oak Ridge Operations Office U.S. Department of Energy

Prepared by Environmental Sciences Division Oak Ridge National Laboratory ESD Publication 2597

OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee 37831-6285 managed by MARTIN MARIETTA ENERGY SYSTEMS, INC. for the U.S. DEPARTMENT OF ENERGY under contract DE-AC05-84OR21400

Executive Summary

Approximately 180 surface-sediment grab samples and three sediment cores were obtained from the Clinch River-Poplar Creek system around the Oak Ridge Gaseous Diffusion Plant (K-25) and screened for metal, organic, and radio-isotope contamination. The results of this scoping study were evaluated to identify potential sources of contamination.

Data from this study indicate that Hg, ¹³⁷Cs, and ⁶⁰Co originate from sources outside K-25. External sources also contribute uranium and miscellaneous organic contamination. Within K-25, the K1700 stream, K901A chromate pond, K710A powerhouse, and K1007B pond appear to be the major areas of contamination. Principal contaminants detected in these areas as a result of this survey were U, Cr, Ni, Cu, Ag, and PCBs.

Although the major areas of contamination have been identified, this report does not attempt to identify the specific sources within K-25 nor to quantify the impact of K-25 sources on the major streams.