We conducted a series of experiments to assess the usefulness of the centrifuge to model the mobility of trace contaminants through soil. Our results illustrate that breakthrough curves from tests conducted at 1g and at accelerations up to 60g overlap for non-sorbing conservative chemicals. This was not the case for lead, a sorbing trace metal, in the soil containing organic matter used in these tests. Our data suggest that a minimum contact time is needed to reach sorption equilibrium between the sorbing chemical and the soil, and that contact times in both centrifuge and 1g breakthrough tests were insufficient. Since minimum contact times will be a function of the soil and the contaminant, more work is needed to assess fate and transport behavior at slower seepage velocities and various combinations of chemicals and soils.
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