Development of a novel method for the determination of aqueous inorganic 129I speciation.

The objective of this research was to develop a method suitable for the determination of aqueous concentrations of radioactive iodine as I2, I(-), and IO3(-). As one of the primary risk-drivers and contaminants of concern at nuclear waste repositories, the accurate determination of (129)I in aqueous systems is of significant concern. The redox-active nature of iodine makes its mobility and fate in the environment difficult to predict, thus underscoring the importance of species-specific determination of iodine concentrations.

Online detection of radioactive iodine in aqueous systems through the use of scintillating anion exchange resin.

The objective of this research was to develop a scintillating anion exchange resin selective for monitoring (129)I at concentrations at or below ~0.4 Bq/L. One of the primary long-term risk-drivers and contaminants associated with nuclear waste sites is (129)I.

Distributions of radionuclide sorption coefficients (Kd) in sub-surface sediments and the implications for transport calculations.

The effect of the spatial variability of K(d) on calculations of contaminant travel time in the vadose zone was determined. Depth discrete measurements of K(d) were made for a suite of radionuclides ((109)Cd, (57)Co, (60)Co, (85)Sr, (137)Cs, and (88)Y) utilizing a sediment core from the E-Area at the Savannah River Site. The K(d)'s were ordered as (85)Sr(2+) < (137)Cs(+) < (109)Cd(2+) < (57)Co(2+) = (60)Co(2+) << (88)Y(3+) and the values generally fell below or near the lowest quartile of values reported in the literature.