As the bulk chlorinated solvent moves through the subsurface, some of the liquid may be trapped in the soil or sediment pores (residual
saturation); some may evaporate (volatilization); some may become sorbed to the surface of the soil particles (sorption) and some may
dissolve in the ground water (dissolved plume). Since bulk chlorinated solvents are more dense than water, the liquid tends to move
down below the water table. As the dissolved plume moves, the concentration of the dissolved solvents is lowered by dispersion and
dilution effects. Microorganisms may degrade hydrocarbons that are dissolved, volatilized or sorbed