General Order 64-A

Section IV

Strength Requirements For All Classes Of Lines

48.5    Foundations.

In calculating the strength of foundations against uplift the weight of concrete shall be taken as 140 pounds per cubic foot and the weight of earth (calculated 30 degrees from the vertical) shall be taken as not more than 90 pounds per cubic foot.  The strength of foundations against depression shall be calculated from the best available data on the soil in question.