1.1 These test methods cover laboratory measurement of the hydraulic conductivity (also referred to as coefficient of permeability) of water-saturated porous materials with a flexible wall permeameter at temperatures between about 15 and 30°C (59 and 86°F). Temperatures outside this range may be used; however, the user would have to determine the specific gravity of mercury and RT (see 10.3) at those temperatures using data from Handbook of Chemistry and Physics. There are six alternate methods or hydraulic systems that may be used to measure the hydraulic conductivity. These hydraulic systems are as follows: 1.1.1 Method A—Constant Head 1.1.2 Method B—Falling Head, constant tailwater elevation 1.1.3 Method C—Falling Head, rising tailwater elevation 1.1.4 Method D—Constant Rate of Flow 1.1.5 Method E—Constant Volume–Constant Head (by mercury)