As a former groundwater quality specialist, even small breaks in confining layers can result in significant transfer of contaminants. And, the direction and rates of water movement can change over time, often from groundwater drilling.

The direction and rates of groundwater flow are evaluated frequently at the site and groundwater samples collected routinely from various hydrogeologic units beneath the facility.  The Remedial Investigation activities also evaluated the areas where the confining layers in the subsurface were not continuous through the completion of soil borings, installation of monitoring wells, collection of groundwater samples, groundwater elevations and completion of aquifer tests to determine hydraulic properties of the groundwater units.  These data will be used for the upcoming evaluation of contaminant movement in the fate and transport evaluation through the use of a 3-dimensional numerical model which will be presented in the Fate and Transport Remedial Investigation Report.