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D. R. Rector contributed to PNNL's FY2000 waste-glass durability investigation, combining dissolution measurements with reactive-transport modelling.^[ref]

The distinction between reaction and transport is essential: a surface can release material rapidly while a restricted pathway exports it slowly. A predictive model must therefore combine chemical source terms with fluid transport, rather than treating an outlet concentration as an intrinsic material constant.

E. A. Rodriguez co-investigated aqueous waste-glass dissolution in PNNL's FY2000 study, which varied solution conditions while measuring constituent release.^[ref]

For the single-pass flow-through leach test, an inlet blank distinguishes material released by the glass from material already present in the feed. Without that subtraction, a small measured outlet concentration need not represent a small net corrosion flux.

H. T. Schaef contributed to the joint PNNL investigation of waste-glass corrosion under controlled solution chemistry and temperature.^[ref]

In dissolution experiments, changing pH changes the chemical environment at the surface. Comparing such tests can probe reaction dependence, provided temperature, available surface area and transport are also controlled.

J. L. Steele contributed to the PNNL study of waste-glass dissolution using controlled flow-through experiments. The joint report relates measured element release to glass durability.^[ref]

The single-pass flow-through leach test measures exported material, not simply a change in the specimen's apparent size. A comparison of released constituents also tests whether the dissolution follows the solid's bulk stoichiometry.

J. P. Icenhower contributed to the joint PNNL programme quantifying waste-glass dissolution and its dependence on solution conditions.^[ref]

Durability comparisons must normalize the exposed surface area and the constituent fraction being measured. Otherwise a change in particle size or bulk composition can masquerade as a different intrinsic corrosion rate.

P. F. Martin co-investigated the durability of low-activity waste glass in the FY2000 PNNL report, including flow-through corrosion tests.^[ref]

A simple mass balance illustrates why volumetric flow rate matters: exported solute per unit time equals volumetric volumetric flow rate times the inlet-to-outlet concentration increase. Equal outlet concentrations at different flow rates therefore need not mean equal release rates.

A single-pass flow-through leach test measures the dissolution of a solid while fresh solution continuously enters a reaction cell and the outlet solution is collected for analysis. Unlike a closed vessel, the cell continually exports dissolved constituents. A reported implementation uses a pump, a solution reservoir, a reaction cell and controlled temperature.^[ref]

At steady state, an elemental mass balance gives the normalized release ratewhere $Q$ is the volumetric volumetric flow rate, $c_e$ is the mass concentration of element $e$, $f_e$ is its initial mass fraction in the solid, and $S$ is the exposed surface area. For example, using litres per day, grams per litre and square metres gives grams of equivalent solid per square metre per day. This expression follows by dividing the exported elemental mass per day by $f_{e}S$.

Changing $Q/S$ changes the accumulation of dissolved material and therefore the chemical affinity for dissolution. A rate independent of further increases in $Q/S$ can help identify a dilute-solution regime. Different elemental release rates can also reveal incongruent dissolution or retention in secondary phases, so interpreting a release rate as whole-solid loss requires an explicit material model.