ABSTRACT
One approach to demonstrating that mass loss is occurring in a groundwater plume may be to assess changes in contaminant flux over time at one distance and/or over distance at one time along the plume. Contaminant flux is usually established by monitoring series of wells placed at right angle to groundwater flow. One plume in the Borden aquifer emanates from an emplaced source of coal tar creosote and fence monitoring results agreed qualitatively with plume-scale mass loss estimates. Another plume from an uncontrolled spill of gasoline demonstrated BTEX mass loss both in the whole plume and in a comparison of mass fluxes across two fences. However, the detailed monitoring required at complex sites limits the practical application of this approach.
