ML21265A549

MNRC Soil Permeability Information

ML21265A549
Person / Time
Site:	University of California-Davis
Issue date:	09/22/2021
From:	McClellan Nuclear Research Center
To:	Office of Nuclear Reactor Regulation
Shared Package
ML21265A540	List: ML21265A541 ML21265A542 ML21265A543 ML21265A544 ML21265A545 ML21265A546 ML21265A547 ML21265A548 ML21265A549 ML21265A550 ML21265A551 ML21265A552 ML21265A553
References
Download: ML21265A549 (1)

Text

The soil on which MNRC is constructed is classified as Xerarents-Urban Land San Joaquin complex 0 to 5% slope. Permeability is described qualitatively as moderate to very slow. Specific values for soil permeability are given as a function of soil depth. The largest permeability (water moves through soil the most quickly) is given as 2.0 inches per hour or 1 foot every 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. For a water table depth of 80 feet this results in a water migration time of 480 hours0.00556 days <br />0.133 hours <br />7.936508e-4 weeks <br />1.8264e-4 months <br /> or 20 days. In some cases, the permeability is thought to be as low as 0.06 inches per hour which would result in a water migration time much larger than 480 hours0.00556 days <br />0.133 hours <br />7.936508e-4 weeks <br />1.8264e-4 months <br />. Therefore, the 36-hour migration value given in the SAR is highly conservative.

Reference:

Soil Survey of Sacramento County California. United States Department of Agriculture. April 1993