HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Foster, G. R. Articles by Hakonson, T. E. Search for Related Content PubMed Articles by Foster, G. R. Articles by Hakonson, T. E. Agricola Articles by Foster, G. R. Articles by Hakonson, T. E.

Predicted Erosion and Sediment Delivery of Fallout Plutonium¹

ABSTRACT

Plutonium (Pu) from fallout after atmospheric explosion of nuclear weapons in the 1950s and 1960s is being redistributed over the landscape by soil erosion and carried on sediment by streams to oceans. Erosion rates computed with the Universal Soil Loss Equation for about 200 000 sample points on nonfederal land across the USA were used to estimate Pu removal rates by soil erosion by water, Pu delivery in several major rivers, and concentration of Pu on the transported sediment. Estimates of average annual Pu delivery on sediment ranged from 0.002% of the initial fallout Pu inventory for the Savannah River basin to 0.08% for the Mississippi River basin. If the deposition of Pu had been uniformly 37 Bq/m², the estimated Pu activity on suspended sediment ranged from about 0.26 Bq/kg of sediment for the Savannah River basin to 0.52 Bq/kg for the Columbia and Rio Grande river basins. After 1000 yr, about 9 to 48% of the initial Pu inventory will remain in U.S. soils that are eroding. Much of the Pu on eroded sediment will travel only a short distance from its origin before its host sediment particles are deposited and permanently located, at least for a few hundred years. As much as 90% of the initially deposited Pu will remain, redistributed over the landscape by erosion and deposition. Although the delivery rate of Pu by rivers will not decrease greatly in the next 100 yr, a significant decrease will likely occur by 1000 yr.

Key Words: radioactive contaminants • nonpoint-source pollution • deposition • sediment yield

¹ Contribution from the Los Alamos Natl. Lab., Environ. Science Group, Los Alamos, NM 87545 (contract W-7405-ENG. 36 with the U.S. Dep. of Energy) in cooperation with the USDA-ARS and USDA-SCS.

² Hydraulic engineer, USDA-ARS, Natl. Soil Erosion Lab., Purdue Univ., W. Lafayette, IN 47907 (on an intergovernmental personnel assignment to Los Alamos Natl. Lab., September 1982–July 1983) and radioecologist, Los Alamos Natl. Lab.

Received for publication February 23, 1984.