Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Randall clay (fine, smectitic, thermic Ustic Epiaquerts) is typical of the soils found in the bottom of playa lakes that are sometimes used as catchments for feedyard runoff in the Texas Panhandle. The objective of this research was to document the time-related sealing properties of cracked Randall Clay when subjected to a rapid infiltration event. Soil cores that were 7.6 cm in diameter by 15 cm deep were collected from two playa lakes in Randall County, Texas. The cores were air dried for one month, and cracking was documented using computer-aided tomography. The soil cores were subjected to infiltration and saturated hydraulic conductivity tests in a flexible wall permeameter. The modified Kostiakov equation was used to describe the infiltration characteristics of each soil core. Cumulative infiltration after 60 minutes varied from 0.15 to 1.60 cm, and the cores effectively sealed before water traveled more than 8 cm. These infiltration rates are lower than values reported in earlier research. Saturated hydraulic conductivities varied from 3.2 x 10 -4 to 7.2 x 10 -7 cm/min with geometric means of 4.1 x 10 -6 and 1.4 x 10 -5 cm/min at the two playas.