Carbon-14 Geochemistry at the Savannah River Site
- Savannah River Site (SRS), Aiken, SC (United States)
Carbon-14 is among the key radionuclides driving risk at the E-Area Low-Level Waste Disposal Facility on the Savannah River Site (SRS). Much of this calculated risk is believed to be the result of having to make conservative assumptions in risk calculations because of the lack of site-specific data. The original geochemical data package (Kaplan 2006) recommended that performance assessments and composite analyses for the SRS assume that 14C did not sorbed to sediments or cementitious materials, i.e., that C-14 Kd value (solid:liquid concentration ratio) be set to 0 mL/g (Kaplan 2006). This recommendation was based primarily on the fact that no site-specific experimental work was available and the assumption that the interaction of anionic 14C as CO2-2) with similarly charged sediments or cementitious materials would be minimal. When used in reactive transport equations, the 0 mL/g Kd value results in 14C not interacting with the solid phase and moving quickly through the porous media at the same rate as water. The objective of this study was to quantify and understand how aqueous 14C, as dissolved carbonate, sorbs to and desorbs from SRS sediments and cementitious materials. Laboratory studies measuring the sorption of 14C, added as a carbonate, showed unequivocally that 14C-carbonate Kd values were not equal to 0 mL/g for any of the solid phases tested, but they required several months to come to steady state.
- Research Organization:
- Savannah River Site (SRS), Aiken, SC (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC09-08SR22470
- OSTI ID:
- 1079895
- Report Number(s):
- SRNS-STI--2008-00445
- Country of Publication:
- United States
- Language:
- English
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