Vitrified waste form performance modeling applied to the treatment and disposal of mixed-waste sludge at the Savannah River Site

Journal Article · Tue Sep 01 04:00:00 EDT 1998 · Nuclear Technology

OSTI ID:655480

Whited, A R; Fjeld, R A ^[1]; Cook, J R ^[2]

---

1. Clemson Univ., SC (United States). Dept. of Environmental Engineering and Science
2. Westinghouse Savannah River Co., Aiken, SC (United States)

Vitrification, the conversion of source components into a solid amorphous glass matrix, has emerged as a viable treatment technology for low-level radioactive waste and mixed waste. To dispose of vitrified low-level waste at US Department of Energy facilities, site-specific radiological performance assessments must be conducted to demonstrate that waste glass satisfies performance objectives for environmental protection. More than 2,500 m{sup 3} of F0006-listed low-level mixed-waste sludge stored in the Reactor Materials Department (M-Area) at the Savannah River Site (SRS) is scheduled for vitrification. This study evaluates the feasibility of on-site disposal of vitrified M-Area waste at SRS. Laboratory leaching tests that accelerate the glass corrosion process are currently the best indicators of vitrified waste form durability. A method to incorporate laboratory leaching data into performance assessments is presented. A screening-level performance assessments code is used to model trench disposal of M-Area waste glass. The allowable leach rate for vitrified M-Area waste is determined based on both a maximum radiological dose equivalent of 4 mrem/yr for the drinking water pathway and a maximum uranium concentration of 20 {micro}g/{ell} in groundwater. The allowable leach rate is compared with published long-term leaching data for a wide range of waste glass compositions and test conditions. This analysis demonstrates that trench disposal of the waste glass is likely to meet applicable performance objectives if the glass is of above average durability compared with the reference set of glasses.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FC09-93SR18262
• OSTI ID: 655480
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 3 Vol. 123; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
CORROSION
GLASS
HAZARDOUS MATERIALS
LEACHING
LOW-LEVEL RADIOACTIVE WASTES
MATHEMATICAL MODELS
PERFORMANCE
RADIONUCLIDE MIGRATION
SAVANNAH RIVER PLANT
VITRIFICATION
WASTE DISPOSAL
WASTE FORMS
WASTE PROCESSING