The effect of soil moisture on chlorine (Cl-2) deposition was examined in laboratory chamber experiments at high Cl-2 exposures by measuring the concentration of chloride (Cl-) in soil columns. Soil mixtures with varying amounts of clay, sand, and organic matter and with moisture contents up to 20% (w/w) were exposed to approximate to 3 x 10(4) ppm Cl-2 vapor. For low water content soils, additional water increased the reaction rate as evidenced by higher Cl- concentration at higher soil moisture content. Results also showed that the presence of water restricted transport of Cl-2 into the soil columns and caused lower overall deposition of Cl-2 in the top 0.48-cm layer of soil when Cl-2 filled approximate to 60% or more of the void space in the column. Numerical solutions to partial differential equations of Fick's law of diffusion and a simple rate law for Cl-2 reaction corroborated conclusions derived from the data. For the soil mixtures and conditions of these experiments, moisture content that filled 30-50% of the available void space yielded the maximum amount of Cl-2 deposition in the top 0.48 cm of soil. Published by Elsevier B.V.