If not utilized immediately, the A and E horizon or other suitable soil materials specified in Section 460:20-49-5(a) (1) and the B horizon or other suitable materials specified in Sections 460:20-49-5(a) (2) and 460:20-49-5(a)(3) shall be stored separately from each other and from spoil. These stockpiles shall be placed within the permit area where they are not disturbed or exposed to excessive water or wind erosion before the stockpiled horizons can be redistributed. Stockpiles in place for more than 30 days shall meet the requirements of Section 460:20-43-7 or 460:20-45-7.
Okla. Admin. Code § 460:20-49-6