(3) Automatic bleeder vents (vacuum breaker vents)
and rim space vents must be equipped with a gasketed lid, pallet,
flapper, or other closure device and must be closed (i.e., no gap
of more than 1/8 inch) at all times except when required to be open
to relieve excess pressure or vacuum in accordance with the manufacturer's
design.
(4) Each opening into the internal floating roof for
a fixed roof support column may be equipped with a flexible fabric
sleeve seal instead of a deck cover.
(5) Any external floating roof drain that empties into
the stored liquid must be equipped with a slotted membrane fabric
cover that covers at least 90% of the area of the opening or an equivalent
control that must be kept in a closed (i.e., no gap of more than 1/8
inch) position at all times except when the drain is in actual use.
Stub drains on an internal floating roof storage tank are not subject
to this requirement.
(6) There must be no visible holes, tears, or other
openings in any seal or seal fabric.
(7) For an external floating roof storage tank, secondary
seals must be the rim-mounted type. The seal must be continuous from
the floating roof to the tank wall, with the exception of gaps that
do not exceed the following specification. The accumulated area of
gaps that exceed 1/8 inch in width between the secondary seal and
storage tank wall may not be greater than 1.0 square inch per foot
of storage tank diameter.
(8) Each opening for a slotted guide pole in an external
floating roof storage tank must be equipped with one of the following
control device configurations:
(A) a pole wiper and pole float that has a seal or
wiper at or above the height of the pole wiper:
(B) a pole wiper and a pole sleeve;
(C) an internal sleeve emission control system;
(D) a retrofit to a solid guide pole system;
(E) a flexible enclosure system; or
(F) a cover on an external floating roof tank.
(9) The external floating roof or internal floating
roof must be floating on the liquid surface at all times, except as
allowed under the following circumstances:
(A) during the initial fill or refill after the storage
tank has been cleaned;
(B) when necessary for preventive maintenance, roof
repair, primary seal inspection, or removal and installation of a
secondary seal, if product is not transferred into or out of the storage
tank, emissions are minimized, and the repair is completed within
seven calendar days;
(C) when the storage tank has a storage capacity less
than 25,000 gallons;
(D) when the vapors are routed to a control device
from the time the storage tank has been emptied to the extent practical
or the drain pump loses suction until the floating roof is within
10% by volume of being refloated;
(E) when all VOC emissions from the storage tank, including
emissions from floating roof landings, have been included in an emissions
limit or cap approved under Chapter 116 of this title (relating to
Control of Air Pollution by Permits for New Construction or Modification)
prior to March 1, 2013; or
(F) when all VOC emissions from floating roof landings
at the regulated entity are less than 25 tons per year.
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