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Fig. 5. Comparison of moisture content in the right and central coarse sand inclusions in Fig. 3 during imbibition. "Height of WT" refers to height of the water in the reservoirs relative to the base of the tank. "Pressure Head" refers to the equivalent pressure head at the measurement point assuming hydrostatic conditions. Within the right sand inclusion, free movement of the air phase allows sequential resaturation at the four TDR locations. In the center sand inclusion, resaturation continues as in the right zone until the overlying fine sand becomes saturated. At that point, air is trapped within the coarse sand and no further significant increase in saturation is observed at the upper two TDR locations despite a rise in the water table to the upper surface of the sand. (After Dunn and Silliman, 2003.)
