40 CFR §264.254

1. (a)During construction or installation, liners (except in the case of existing portions of piles exempt from § 264.251(a)) and cover systems (e.g., membranes, sheets, or coatings) must be inspected for uniformity, damage, and imperfections (e.g., holes, cracks, thin spots, or foreign materials). Immediately after construction or installation:
   1. (1)Synthetic liners and covers must be inspected to ensure tight seams and joints and the absence of tears, punctures, or blisters; and
   2. (2)Soil-based and admixed liners and covers must be inspected for imperfections including lenses, cracks, channels, root holes, or other structural non-uniformities that may cause an increase in the permeability of the liner or cover.
2. (b)While a waste pile is in operation, it must be inspected weekly and after storms to detect evidence of any of the following:
   1. (1)Deterioration, malfunctions, or improper operation of run-on and run-off control systems;
   2. (2)Proper functioning of wind dispersal control systems, where present; and
   3. (3)The presence of leachate in and proper functioning of leachate collection and removal systems, where present.
3. (c)An owner or operator required to have a leak detection system under § 264.251(c) must record the amount of liquids removed from each leak detection system sump at least once each week during the active life and closure period.