Effect of Saline Waste Solution Infiltration Rates on Uranium Retention and Spatial Distribution in Hanford Sediments

Journal Article · Sat Mar 15 04:00:00 EDT 2008 · Environmental Science & Technology, 42(6):1973-1978

DOI:https://doi.org/10.1021/es070684b· OSTI ID:926518

Wan, Jiamin; Tokunaga, Tetsu K; Kim, Yongman; Wang, Zheming; Lanzirotti, Anthony; Saiz, Eduardo; Serne, R Jeffrey

The accidental overfilling of waste liquid from tank BX-102 at the Hanford Site 11 in 1951 put 10 metric tons of U(VI) in the vadose zone. In order to understand the dominant 12 geochemical reactions and transport processes occurred during the initial infiltration, and to 13 predict U current status and future mobility, we simulated the waste liquid spilling event in 14 laboratory sediment columns using synthesized metal waste solution. We found that, as the 15 plume propagating through sediments, dramatic pH reduction (up to 4 units) occurred at moving 16 plume fronts. Massive amounts of colloids, including U-colloids, formed at plume fronts. The 17 infiltration flow rates strongly affect U fate and transport. Slower flow rate resulted in higher 18 sediment-associated U concentrations, and higher flow rate permitted practically unretarded U 19 transport, and extensive colloid precipitation and accumulations at the plume fronts. Accelerated 20 U transport by size exclusion of U-colloids was revealed. U exceeded the source concentration of 21 U by up to 5 fold, and exceeded the source concentrations of sodium, carbonate, phosphate and 22 sulfate by much more. This first report of colloid induced accelerated U transport could be a 23 mechanism responsible for highly heterogeneous U distributions in the sediment and deep 24 migration to the groundwater.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 926518
• Report Number(s): PNNL-SA-56426; 25656; KP1302000
• Journal Information: Environmental Science & Technology, 42(6):1973-1978, Journal Name: Environmental Science & Technology, 42(6):1973-1978 Journal Issue: 6 Vol. 42
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
ADSORPTION
COLLOIDS
ENVIRONMENTAL TRANSPORT
Environmental Molecular Sciences Laboratory
FLOW RATE
GEOCHEMISTRY
HANFORD RESERVATION
HAZARDOUS MATERIALS SPILLS
LIQUID WASTES
RADIOACTIVE WASTES
SPATIAL DISTRIBUTION
TRLIF
URANIUM
fluorescence
transport
uranium plume
uranyl
vadose zone