Fixation Mechanisms and Desorption Rates of Sorbed Cs in High-Level Waste Contaminated Subsurface Sediments: Implications to Future Behavior and In-Ground Stability
The high-yield fission product 137Cs is a major contaminant of the vadose zone at Hanford and other DOE sites. Over 100 kCi of 137Cs was discharged to the vadose zone in the S-SX tank farm at Hanford through the leakage of high-level waste from tanks SX-108 and SX-109. Although 137Cs is strongly sorbed by subsurface sediments, certain waste characteristics, such as high Na+, can expedite its migration and reduce its retardation to low values. This project is focused on defining the in-ground geochemistry of sorbed 137Cs released from high-level waste tanks, so that better future projections can be made of Cs mobility in the vadose zone. The project will study Cs-contaminated subsurface sediments from various Hanford tank farms to (1) determine the mineralogic and surface site residence of sorbed Cs in contaminated sediments varying in current Cs content and original waste composition, (2) establish geochemical factors and processes controlling Cs desorbability and desorption kinetics from contaminated sediment and Cs-enriched sediment particles, and (3) define and parameterize a kinetic model for Cs desorption that incorporates multi-site behavior and heterogeneous intraparticle Cs distribution.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE Office of Environmental Management (EM) (US)
- OSTI ID:
- 833767
- Report Number(s):
- EMSP-73758-2001; R&D Project: EMSP 73758; TRN: US200430%%1814
- Resource Relation:
- Other Information: PBD: 1 Jun 2001
- Country of Publication:
- United States
- Language:
- English
Similar Records
Mineralogic Residence and Desorption Rates of Sorbed 90Sr in Contaminated Subsurface Sediments: Implications to Future Behavior and In-Ground Stability
Role of Competitive Cation Exchange on Chromatographic Displacement of Cesium in the Vadose Zone beneath the Hanford S/SX Tank Farm