Verification of the integrity of barriers using gas diffusion

In-situ barrier materials and designs are being developed for containment of high risk contamination as an alternative to immediate removal or remediation. The intent of these designs is to prevent the movement of contaminants in either the liquid or vapor phase by long-term containment, essentially buying time until the contaminant depletes naturally or a r mediation can be implemented. The integrity of the resultant soil-binder mixture is typically assessed by a number of destructive laboratory tests (leaching, compressive strength, mechanical stability with respect to wetting and freeze-thaw cycles) which as a group are used to infer the likelihood of favorable long-term performance of the barrier. Scaling up the laboratory methods to field situations presents serious technical challenges, such tests would render the waste form useless for its long-term purpose of waste isolation. The need exists for a minimally intrusive yet quantifiable methods for assessment of a barrier’s integrity after emplacement, and monitoring of the barrier's performance over its lifetime. A non-destructive test is needed that can be performed at both the laboratory and field scales, and 4that directly measures the properties of interest or is correlated with them. Here, we evaluat