THE FORMATION OF FLUID MIGRATION PATHWAYS THROUGH UTILITY CONSTRUCTION

Fluid migration pathways are formed during the construction of utilities and are particularly active in areas where the original, undisturbed earth is dense and is resistant to fluid migration itself. The disturbance of this dense earth and its replacement with porous pipe bedding materials creates a conduit by which fluid can travel from one location to another and potentially escape into the environment.Gaseous methane migration at the Archmont Knolls housing development in the Town of Colonie, New York and free product liquid contaminant migration at the United States Naval base at Pearl Harbor, Hawaii are presented as examples of situations where fluid migration has been observed and remediated.Systems employed to mitigate fluid migration pathways can be categorized as migration pathway interrupters and migration pathway interceptor/relievers. Counter-measure techniques are discussed in their application at the example sites.Preconstruction investigations are critical to preventing the formation of fluid migration pathways. Historical reviews, field inspections and subsurface investigations can provide the data necessary for fluid identification and the assessment of pathway formation. It is imperative that those collecting and analyzing data are aware of the potential for migration and incorporate the measures necessary to prevent transport and release of fluids through utility corridors into their designs.