The paper discusses preferential radon transport through highly permeable channels in soils. Indoor radon levels (that can pose a serious health risk) can be dramatically increased by air that is drawn into buildings through pipe penetrations that connect to permeable channels in soils. The channels, commonly containing gravel bedding around utility pipes, act as a collecting plenum for soil radon and can draw air from distances approaching 100 m. Equations characterizing air and radon flow in such channels are developed and compared with field data in this paper. Three test channels were constructed to simulate conditions associated with utility line installations. Site sampling characterized soil radium, emanation, moisture, particle size, density, specific gravity, permeability, and diffusion coefficient properties.