NAC445A.438. Minimum design criteria: Liners.

     1. When placed on native materials, soil liners must have a minimum thickness of 12 inches and be compacted in lifts which are no more than 6 inches thick. Except when used in tailing impoundments, a soil liner must have a permeability of not more than that exhibited by 12 inches of 1x10-7 cm/sec material.

     2. Synthetic liners must be rated as having a resistance to the passage of process fluids equal to a coefficient of permeability of 1x10-11 cm/sec.

     3. The Department shall review for completeness the applicant’s evaluation of the following design parameters, where applicable, for a liner:

     (a) The type of foundation, slope and stability;

     (b) The over liner protection and provisions for hydraulic relief;

     (c) The load and means of applying load;

     (d) The compatibility of a liner with process solutions;

     (e) The complexity of the leak detection and recovery systems;

     (f) The depth from the surface to all groundwater; and

     (g) The liner’s ability to remain functionally competent until permanent closure has been completed.

     (Added to NAC by Environmental Comm’n, eff. 9-1-89)—(Substituted in revision for NAC 445.2437)