Related Experiment Video
Updated: Apr 27, 2026
08:53
Automated 90Sr Separation and Preconcentration in a Lab-on-Valve System at Ppq Level
Published on: June 6, 2018
8.4K
Long-term radiostrontium interactions and transport through sediment
Daniel I Kaplan1, Todd J Miller, David Diprete
1Savannah River National Laboratory, Aiken, South Carolina 29803, United States.
Environmental Science & Technology
|June 25, 2014
Summary
Radioactive strontium transport in soil and groundwater was studied over 11 years. A secondary, slow sorption process significantly impacts strontium mobility, affecting long-term contaminant modeling.
Area of Science:
- Environmental Science
- Geochemistry
- Radiochemistry
Background:
- Radioactive strontium is a prevalent radiological contaminant in soil and groundwater.
- Understanding strontium's long-term transport is crucial for environmental remediation and nuclear waste management.
Purpose of the Study:
- To evaluate strontium (Sr) transport in soil over an 11-year field lysimeter study.
- To quantify secondary aging effects on Sr-sediment interactions for improved long-term transport modeling.
Main Methods:
- Conducted batch sorption/desorption tests using Sr isotopes (85Sr, 88Sr, 90Sr) and sediment from a long-term lysimeter.
- Performed numerical modeling of 90Sr depth profiles using field data.
- Analyzed Sr sorption coefficients (Kd) after varying contact periods.
Main Results:
- Strontium exhibited largely reversible and linear sorption behavior.
- Sorption coefficients (Kd) after 23 days were comparable to desorption Kd values after 24 years.
- Numerical modeling indicated a Kd of 32 mL g(-1) best fit the lysimeter data, though it overestimated mobility below the source term.
Conclusions:
- A single Kd value adequately described most Sr transport trends.
- A slower, secondary sorption reaction occurring over months to decades likely explains the overestimation of Sr mobility below the source.
- This secondary aging effect is critical for accurate long-term strontium transport modeling.
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