Geochemical Modeling of F Area Seepage Basin Composition and Variability

Identifying key controls on the behavior of an acidic-U(VI) plume in the Savannah River Site using reactive transport modeling

“…1A) during the site operations, the pH of the discharge entering the subsurface from the largest of the basins (F-3) was mostly likely fairly constant and low (Millings et al, 2012). The processes affecting the migration of acidic solutions through the vadose zone below the F-3 basin are similar to those previously evaluated with simpler models of the F-Area saturated zone (e.g., Spycher et al, 2011).…”

A New Paradigm for Long Term Monitoring at the F-Area Seepage Basins, Savannah River Site

“…Disposal of waste into the basins began in 1955 and ended in 1988. During basin operation, the concentration of radionuclides entering the basins varied considerably, but these variations were dampened by mixing in the basins (Millings et al, 2012) and by processes that occurred during migration through the vadose zone. Closure and installation of a low permeability cap over the basins was completed in 1991.…”

Sustainable Remediation in Complex Geologic Systems

“…The discharge rate and contaminant concentration in the source needs to be quantified. Historical operation records are critical in this process (e.g., Refs 28,29). If the contamination has occurred already, the plume extent needs to be characterized through groundwater monitoring.…”

“…28 Process wastes were discharged into the F-area seepage basins followed by subsequent mixing processes within the basins and eventual infiltration into the subsurface. 29 Millings et al 29 performed geochemical modeling to evaluate the importance of the wide variability in bulk wastewater chemistry over time as it propagated through the basins. They showed that the largest basin (Basin 3) is the primary contaminant source to the groundwater and that the fluctuation in chemistry of the waste streams is not directly representative of the source term to the vadose zone.…”