Evaluation of cobalt mobility in soils from the Nevada Test Site

Technical Report · Sun Sep 01 04:00:00 EDT 1996

DOI:https://doi.org/10.2172/417003· OSTI ID:417003

Papelis, C

Nuclear testing at and around the Nevada Test Site (NTS) resulted in widespread contamination from transuranic and other radionuclides, as well as from other toxic inorganic and organic contaminants. The type of contamination, including spatial distribution and type of radionuclides present, depends on the type of testing performed. Remediation of the contaminated areas is currently under way. The optimum in situ or ex situ remediation technology depends on the degree of interaction between the particular radionuclide, or contaminant in general, and the soil matrix, among other factors. The objective of this project was to evaluate the sorption affinity of NTS soils for common non-transuranic radionuclides. The sorption of cobalt (Co) on soils from two different areas of the NTS, namely the Little Feller and Cabriolet event sites, was studied. Experiments were conducted as a function of pH, solid concentration, total Co concentration, ionic strength, and particle size fraction. Preliminary results indicate that both soils have a high sorption capacity for Co. The results suggest that Co uptake is controlled by sorption on either internal, permanent-charge, ion-exchange sites of clay minerals or on amphoteric, surface-hydroxyl sites of oxides. The results further indicate strong retardation of Co in these soils, under most conditions tested and expected to be found in the respective soil environments. These conclusions are applicable to transport of radionuclides which are expected to bind strongly on oxide surfaces (e.g., Co) but the results may not be representative of the behavior of weakly binding radionuclides. These studies clearly demonstrate the importance of evaluating the mobility of radionuclides and the degree of radionuclide-soil interaction before final selection of an in situ or ex situ remediation technology for a contaminated site.

• Research Organization: University and Community Coll. System of Nevada, Reno, NV (United States)
• Sponsoring Organization: USDOE Office of Environmental Restoration and Waste Management, Washington, DC (United States)
• DOE Contract Number: AC08-90NV10845
• OSTI ID: 417003
• Report Number(s): DOE/NV/10845--58; ON: DE97001628
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
COBALT
ENVIRONMENTAL TRANSPORT
NEVADA TEST SITE
RADIOECOLOGICAL CONCENTRATION
RADIOISOTOPES
REMEDIAL ACTION
SITE CHARACTERIZATION
SOILS
SORPTIVE PROPERTIES