Current through Register Vol. 47, No. 17, September 10, 2024
(a)
During construction and installation, liners (except in the case of existing
portions of surface impoundments exempt from § 264.221(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) Synthetic liners and covers must be
inspected to ensure tight seams and joints and the absence of tears, punctures,
or blisters; and
(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.
(b) While a
surface impoundment is in operation, it must be inspected weekly and after
storms to detect evidence of any of the following:
(1) Deterioration, malfunctions, or improper
operation of overtopping control systems;
(2) Sudden drops in the level of the
impoundment's contents; and
(3)
Severe erosion or other signs of deterioration in dikes or other containment
devices.
(c) Prior to the
issuance of a permit, and after any extended period of time (at least six
months) during which the impoundment was not in service, the owner or operator
must obtain a certification from a qualified engineer that the impoundment's
dike, including that portion of any dike which provides freeboard, has
structural integrity. The certification must establish, in particular, that the
dike:
(1) Will withstand the stress of the
pressure exerted by the types and amounts of wastes to be placed in the
impoundment; and
(2) Will not fail
due to scouring or piping, without dependence on any liner system included in
the surface impoundment construction.
(d)
(1) An
owner or operator required to have a leak detection system under §
264.221(c) or (d) 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.
(2) After the final
cover is installed, the amount of liquids removed from each leak detection
system sump must be recorded at least monthly. If the liquid level in the sump
stays below the pump operating level for two consecutive months, the amount of
liquids in the sumps must be recorded at least quarterly. If the liquid level
in the sump stays below the pump operating level for two consecutive quarters,
the amount of liquids in the sumps must be recorded at least semi-annually. If
at any time during the post-closure care period the pump operating level is
exceeded at units on quarterly or semi-annual recording schedules, the owner or
operator must return to monthly recording of amounts of liquids removed from
each sump until the liquid level again stays below the pump operating level for
two consecutive months.
(3) "Pump
operating level" is a liquid level proposed by the owner or operator and
approved by the Department based on pump activation level, sump dimensions, and
level that avoids backup into the drainage layer and minimizes head in the
sump.
