1.1 ,This test method covers laboratory measurement of the hydraulic conductivity (also referred to as coefficient of permeability) of water-saturated samples obtained from materials derived from scrap tires using a rigid-wall permeameter. The scrap tire materials covered in this method include tire chips, tire shreds, and tire derived aggregate (TDA) as described in Practice D6270 with particle sizes ranging from approximately 12 to 305 mm. Whole scrap tires are not included in this standard. A clear trend between hydraulic conductivity and shred size has not been established at a given vertical pressure for shreds ≥,50 mm (1).2