130 Neb. Admin. Code, ch. 8, § 007
Any new livestock waste control facilities or any expansion of a livestock waste control facility shall be constructed in a location and with soils that are structurally capable of supporting the liner and meeting the percolation limits as applicable. Earthen liners shall be constructed of materials and with construction methods so that percolation does not exceed 0.13 inches per day ( 3.82 x 10-6 cm/sec). The design shall specify liner thickness. Where a flexible membrane liner is used, a properly compacted soil sub-base shall be constructed below the liner with a minimum thickness of six inches. Structural determinations are required for earthen structures that are steeper than 2 horizontal to 1 vertical for proposed facilities. Verification of the percolation rate is required, in a manner approved by the Department, for all earthen liners. Seam testing for flexible membrane liners is required to verify watertight seams.
130 Neb. Admin. Code, ch. 8, § 007