Assessment of the Sources and Fates of Radioisotopes Delivered to the Kara Sea and Adjacent Arctic.
Final technical rept. 1 May 93-30 Apr 96,
WOODS HOLE OCEANOGRAPHIC INST MA DEPT OF MARINE CHEMISTRY AND GEOCHEMISTRY
Pagination or Media Count:
This project originated in an attempt to characterize the history of transport of radioactive contaminants in the Ob River, the fate of these contaminants within the river system, and their transport down the river to the estuary and Arctic Ocean. Our focus has been on the particle reactive contaminants Cs137, Np237, Pu238, Pu239, Pu240 and Pb210. Expeditions were carried out to collect sediment cores from small lakes common on the Ob flood plain. The results may be summarized briefly as follows 1 the sediments of the sor lakes of the flood plain do preserve records of the depositional history of the radioactive contaminants studied that extend to the prenuclear age. 2 All of the delta cores are similar in that they exhibit a strong maximum in both Pu isotopes and Cs137 at depth in the cores. 3 Based on Pu239Cs240 and Pu238Pu239,240 ratios, the chronology of the cores, and similarities between the Ob cores and one from the Taz River, a river with no nuclear facilities, we concluded that the Pu and Cs137 were derived from global fallout. 4 Uncertainties in our calculations would permit up to 20 of these contaminants to be derived from non-fallout sources.
- Radiation Pollution and Control