SOIL AS A TERRESTRIAL SINK FOR METHYL-BROMIDE FUMIGANT - PRELIMINARY-RESULTS

Air and surface soil samples were taken at three stations downwind of a strip of soil fumigated with injected methyl bromide. Integrated hor izontal flux of methyl bromide at each sampling station showed the rem oval of similar to 46% of the methyl bromide mass from the plume by th e time it reached 30-60 m downwind. Based on the U.S. EPA's dispersion model SCREEN-3, a mass loss of similar to 42% was estimated. Analysis of the surface soil samples indicated the presence of methyl bromide residues that declined in concentration with distance downwind from th e source. Laboratory tests confirmed the first-order rapid uptake (2-4 minutes) of methyl bromide by field soil. (C) 1997 Elsevier Science L td.