ISSN:
1435-0661
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
a s) ranging from 3.83 to 2.85. Bromide was included in many of the solutions to evaluate the influence of ionic strength and competition for anion-exchange sites on FBA mobility. Despite possible differences in the mechanisms of sorption, retardation within surface and subsurface materials increased with increasing pKa of a given FBA compound. Retardation was attributed to partitioning to the organic fraction for the surface soil and to sorption by Fe oxides for the subsurface sample. For the transport of mixed-benzoate solutions through surface soil, 2,6-di-FBA, 2,3,4,5-tetra-FBA, and Br- yielded transport velocities consistent with those observed for 3H; however, 3,4,5-tri-FBA and 3,4-di-FBA were significantly retarded, most likely due to partitioning to the organic fraction. For the subsurface sample, all of the FBA tracers and Br- were retarded compared with 3H, with FBA retardation increasing with pKa. At higher ionic strengths, retardation was reduced in the subsurface sample due to competition with Br- for anion sorption sites.
Type of Medium:
Electronic Resource
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