Illinois Administrative Code › Title 35 - ENVIRONMENTAL PROTECTION › Part 218 - ORGANIC MATERIAL EMISSION STANDARDS AND LIMITATIONS FOR THE CHICAGO AREA › Subpart B - ORGANIC EMISSIONS FROM STORAGE AND LOADING OPERATIONS › Section 218.120 - Control Requirements for Storage Containers of VOL

Current through Register Vol. 48, No. 28, July 12, 2024
a) Every owner or operator storing VOL in a
				vessel of 40,000 gallons or greater with a maximum true vapor pressure equal to
				0.75 psia but less than 11.1 psia shall reduce VOM emissions from storage
				tanks, reservoirs, or other containers as follows:
1) Each fixed roof tank shall be equipped
				with an internal floating roof that meets the following specifications or that
				is equipped with a vapor control system that meets the specifications contained
				in subsection (a)(4) below:
A) The internal
				floating roof shall rest or float on the liquid surface (but not necessarily in
				complete contact with it) inside a storage vessel that has a fixed roof. The
				internal floating roof shall be floating on the liquid surface at all times,
				except during initial fill and during those intervals when the storage vessel
				is completely emptied and subsequently refilled. When the roof is resting on
				the leg supports, the process of filling, emptying, or refilling shall be
				continuous and shall be accomplished as rapidly as possible.
B) Each internal floating roof shall be
				equipped with one of the following closure devices between the wall of the
				storage vessel and the edge of the internal floating roof:
i) A foam- or liquid-filled seal mounted in
				contact with the liquid (liquid-mounted seal). A liquid-mounted seal means a
				foam- or liquid-filled seal mounted in contact with the liquid between the wall
				of the storage vessel and the floating roof continuously around the
				circumference of the tank;
ii) Two
				seals mounted one above the other so that each forms a continuous closure that
				completely covers the space between the wall of the storage vessel and the edge
				of the internal floating roof. The lower seal may be vapor-mounted, but both
				must be continuous; or
iii) A
				mechanical shoe seal, which is a metal sheet held vertically against the wall
				of the storage vessel by springs or weighted levers and is connected by braces
				to the floating roof. A flexible coated fabric (envelope) spans the annular
				space between the metal sheet and the floating roof.
C) Each opening in a noncontact internal
				floating roof except for automatic bleeder vents (vacuum breaker vents) and the
				rim space vents is to provide a projection below the liquid surface.
D) Each opening in the internal floating roof
				except for leg sleeves, automatic bleeder vents, rim space vents, column wells,
				ladder wells, sample wells, and stub drains is to be equipped with a cover or
				lid which is to be maintained in a closed position at all times (i.e., no
				visible gap) except when the device is in actual use. The cover or lid shall be
				equipped with a gasket. Covers on each access hatch and automatic gauge float
				well shall be bolted except when they are in use.
E) Automatic bleeder vents shall be equipped
				with a gasket and are to be closed at all times when the roof is floating
				except when the roof is being floated off or is being landed on the roof leg
				supports.
F) Rim space vents shall
				be equipped with a gasket and are to be set to open only when the internal
				floating roof is not floating or at the manufacturer's recommended
				setting.
G) Each penetration of the
				internal floating roof for the purpose of sampling shall be a sample well. The
				sample well shall have a slit fabric cover that covers at least 90 percent of
				the opening.
H) Each penetration of
				the internal floating roof that allows for passage of a ladder shall have a
				gasketed sliding cover.