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Oklahoma SIP: OAC 252:100-39 PART 5 Petroleum Processing and Storage

Regulatory Text:

252:100-39-30.  Petroleum liquid storage in external floating roof tanks

252:100-39-30.  Petroleum liquid storage in external floating roof tanks

(As approved by EPA 11/03/1999 (64 FR 59629) at 52.1920(c)(48) effective 01/03/2000.)

     (a)  Definitions.  The following words and terms, when used in this Section, shall have the following meaning, unless the context clearly indicates otherwise:
          (1)  "Condensate" means hydrocarbon liquid separated from natural gas which condenses due to changes in the temperature and/or pressure and remains liquid at normal operating conditions.
          (2)  "Crude oil" means a naturally occurring hydrocarbon mixture which is a liquid at standard conditions. It may contain sulfur, nitrogen and/or oxygen derivatives of hydrocarbon.
          (3)  "External floating roof" means a storage vessel cover in an open top tank consisting of a double deck or pontoon single deck which rests upon and is supported by the petroleum liquid being contained and is equipped with a closure seal or seals to close the space between the roof edge and tank wall.
          (4)  "Lease custody transfer" means the transfer of produced crude oil and/or condensate, after processing and/or treating in the producing operations, from storage tanks or automatic transfer facilities to pipelines or any other forms of transportation.
          (5)  "Liquid-mounted seal" means primary seal mounted in continuous contact with the liquid between the tank wall and the floating roof.
          (6)  "Petroleum liquid" means crude oil, condensate, and any finished or intermediate liquid products manufactured or extracted in petroleum refinery.
          (7)  "Vapor-mounted seal" means a primary seal mounted so there is an annular vapor space underneath the seal.  The annular vapor space is bounded by the bottom of the primary seal, the tank wall, the liquid surface, and the floating roof.
          (8)  "Waxy, high pour point crude oil" means a crude oil with a pour point of 50°F. or higher as determined by the American Society of Testing and Materials Standard D97-66, "Test for Pour Point of Petroleum Oils."

     (b)  Applicability.
          (1)  This Section applies to all source facilities with petroleum liquid storage vessels equipped with external floating roofs, having capacities greater than 150,000 liters (40,000 gallons), that are located in Tulsa and Oklahoma Counties.
          (2)  This Section does not apply to petroleum liquid storage vessels which prior to custody transfer:
               (A)  are used to store waxy, high pour point crude oil;
               (B)  have capacities less than 1,600,000 liters (420,000 gallons) and are used to store produced crude oil and condensate;
               (C)  contain a petroleum liquid with a true vapor pressure less than 10.5 kPa (1.5 psia);
               (D)  contain a petroleum liquid with a true vapor pressure less than 27.6 Kpa (4.0 psia); and,
                    (i)  are of welded construction; and,
                    (ii) presently possess a metallic-type shoe seal, a liquid-mounted foam seal, a liquid-mounted liquid filled type seal, or other closure device of demonstrated equivalence approved by the  Executive Director; or,
               (E)  are of welded construction, equipped with a metallic-type shoe primary seal and has a secondary seal from the top of the shoe seal to the tank wall (shoe-mounted secondary seal).

     (c)  Provisions for specific processes.
          (1)  No owner of a petroleum liquid storage vessel subject to this Section shall store a petroleum liquid in that vessel unless:
               (A)  The vessel has been fitted with;
                    (i)  a continuous secondary seal extending from the floating roof to the tank wall (rim-mounted secondary seal); or,
                    (ii)  a closure or other device which controls VOC emissions with an effectiveness equal to or greater than a seal required above under 252:100-39-30(c)(1)(A)(i) and approved by the  Executive Director.
               (B)  All seal closure devices meet the following requirements;
                    (i)  there are no visible holes, tears, or other openings in the seal(s) or seal fabric;
                    (ii)  the seal(s) are intact and uniformly in place around the circumference of the floating roof between the floating roof and the tank wall; and,
                    (iii)  for vapor mounted primary seals, the accumulated area of gaps exceeding 0.32 cm (1/8 in.) in width between the secondary seal and the tank wall shall not exceed 21.2 cm2 per meter of tank diameter (1.0 in2 per foot of tank diameter), as determined by physically measuring the length and width of all gaps around the entire circumference of the secondary seal in each place where a 0.32 cm uniform diameter probe passes freely between the seal and the tank wall; and summing the area of the individual gaps.
               (C)   All openings in the external floating roof, except for automatic bleeder vents, rim space vents, and leg sleeves, are;
                    (i)  equipped with covers, seals, or lids in the closed position except when the openings are in actual use; and,
                    (ii)  equipped with projections into the tank which remain below the liquid surface at all times;
               (D)  Automatic bleeder vents are closed at all times except when the roof is floated off or landed on the roof leg supports;
               (E)  Rim vents are set to open when the roof is being floated off the leg supports or at the manufacturer's recommended settings; and,
               (F)  Emergency roof drains are provided with slotted membrane fabric covers or equivalent covers which cover at least 90 percent of the area of the opening.
          (2)  The owner or operator of a petroleum liquid storage vessel with an external floating roof subject to this Section shall:
               (A)  perform routine inspections semi-annually in order to ensure compliance with 252:100-39-30(c)(1)(B)(i), i.e., no visible holes, tears, or other openings in the seals or seal fabric;
               (B)  measure the secondary seal gap annually in accordance with 252:100-39-30(c)(1)(B)(iii), when the floating roof is equipped with a vapor-mounted primary seal; and,
               (C)   maintain records of the types of volatile petroleum liquids stored, the true vapor pressure of the liquid as stored, and the results of the inspections performed in 252:100-39-30(c)(2)(A) and 252:100-39-30(c)(2)(B).
          (3)  Copies of all records under 252:100-39-30(c)(2) shall be retained by the owner or operator for a minimum of two years after the date on which the record was made.
          (4)  Copies of all records under this Section shall be made available to the  Executive Director, upon verbal or written request, at any reasonable time.

     (d)  Compliance schedule.  Compliance with this Section will be accomplished by affected facilities within two years of approval of this Section by the Oklahoma  Environmental Quality Board.