Fissure desorption experiments

Fissure Desorption Experiments. Desorption experiments were performed with two fissures by injecting rock equilibrated water into the fissures immediately after removing the americium-bearing solution from the fissures in adsorption experiments. After injection, the rock-equilibrated water was allowed to react within the fissures for a period of time before removal. The rock-equilibrated water was assayed after removal from the two fissures and the amount of nuclide desorbed as a function of contact time was determined. Between five and seven desorption experiments were performed for each of six time periods between ten seconds and sixty minutes for each of the two fissures. The results of the desorption experiments are presented in table 2 as the percent of 3 (at equilibrium) that desorbed from the fissures in a period of time. 

Table II. Am Desorption from Gray Hornblende Schist Fissure Experiments (static)...

Model Predictions. The rate for desorption of americium from the fissure surfaces into solution was assumed to equal the rate for the adsorption of americium from solution by the fissure surfaces. The sorption rate and the equilibrium fractionation of americium that were determined in the static experiments were used to determine input parameters to the ARDISC model. The ARDISC model predictions for the distributions of americium on the fissure surfaces in both sets of experiments are presented in Figures 5 through 10 along with the autoradiographs and the experimental histograms representing the various distributions of americium on the fissure surfaces. 

---