NR 440.28(2)(a)(a) “Condensate” means hydrocarbon liquid separated from natural gas which condenses due to changes in the temperature or pressure, or both, and remains liquid at standard conditions.
NR 440.28(2)(b)(b) “Custody transfer” means the transfer of produced petroleum or condensate, or both, after processing or treating, or both, in the producing operations, from storage tanks or automatic transfer facilities to pipelines or any other forms of transportation.
NR 440.28(2)(c)(c) “Liquid-mounted seal” means a foam or liquid-filled primary seal mounted in contact with the liquid between the tank wall and the floating roof continuously around the circumference of the tank.
NR 440.28(2)(d)(d) “Metallic shoe seal” includes but is not limited to a metal sheet held vertically against the tank wall 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.
NR 440.28(2)(e)(e) “Petroleum” means the crude oil removed from the earth and the oils derived from tar sands, shale and coal.
NR 440.28(2)(f)(f) “Petroleum liquids” means petroleum, condensate, and any finished or intermediate products manufactured in a petroleum refinery but does not mean Nos. 2 through 6 fuel oils as specified in ASTM D396-98, gas turbine fuel oils Nos. 2-GT through 4-GT as specified in ASTM D2880-96, or diesel fuel oils Nos. 2-D and 4-D as specified in ASTM D975-98a. These 3 ASTM methods are incorporated by reference in s. NR 440.17 (2) (a) 13., 36. and 14., respectively.
NR 440.28(2)(g)(g) “Petroleum refinery” means each facility engaged in producing gasoline, kerosene, distillate fuel oils, residual fuel oils, lubricants, or other products through distillation of petroleum or through redistillation, cracking, extracting or reforming of unfinished petroleum derivatives.
NR 440.28(2)(h)(h) “Reid vapor pressure” is the absolute vapor pressure of volatile crude oil and volatile nonviscous petroleum liquids, except liquified petroleum gases, as determined by ASTM D323-94, incorporated by reference in s. NR 440.17 (2) (a) 11.
NR 440.28(2)(i)(i) “Storage vessel” means each tank, reservoir or container used for the storage of petroleum liquids, but does not include:
NR 440.28(2)(i)1.1. Pressure vessels which are designed to operate in excess of 204.9 kPa (15 psig) without emissions to the atmosphere except under emergency conditions.
NR 440.28(2)(i)2.2. Subsurface caverns or porous rock reservoirs, or
NR 440.28(2)(i)3.3. Underground tanks if the total volume of petroleum liquids added to and taken from the tank annually does not exceed twice the volume of the tank.
NR 440.28(2)(j)(j) “True vapor pressure” means the equilibrium partial pressure exerted by a petroleum liquid such as determined in accordance with methods described in American Petroleum Institute Publication 2517, Evaporation Loss from External Floating Roof Tanks, Second Edition, February 1980, incorporated by reference in s. NR 440.17.
NR 440.28(2)(k)(k) “Vapor-mounted seal” means a foam-filled primary seal mounted continuously around the circumference of the tank 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.
NR 440.28(3)(3)Standard for volatile organic compounds (VOC).
NR 440.28(3)(a)(a) The owner or operator of each storage vessel to which this section applies which contains a petroleum liquid which, as stored, has a true vapor pressure equal to or greater than 10.3 kPa (1.5 psia) but not greater than 76.6 kPa (11.1 psia) shall equip the storage vessel with one of the following:
NR 440.28(3)(a)1.1. An external floating roof, consisting of a pontoon-type or double-deck-type cover that rests on the surface of the liquid contents and is equipped with a closure device between the tank wall and the roof edge. Except as provided in subd. 1. b. 4), the closure device shall consist of 2 seals, one above the other. The lower seal is referred to as the primary seal and the upper seal is referred to as the secondary seal. The roof shall be floating on the liquid at all times (i.e., off the roof leg supports) except during initial fill and when the tank is completely emptied and subsequently refilled. The process of emptying and refilling when the roof is resting on the leg supports shall be continuous and shall be accomplished as rapidly as possible.
NR 440.28(3)(a)1.a.a. The primary seal shall be either a metallic shoe seal, a liquid-mounted seal, or a vapor-mounted seal. Each seal shall meet the following requirements:
1) The accumulated area of gaps between the tank wall and the metallic shoe seal or the liquid-mounted seal may not exceed 212 cm2 per meter of tank diameter (10.0 in2 per ft of tank diameter) and the width of any portion of any gap may not exceed 3.81 cm (1.50 in).
2) The accumulated area of gaps between the tank wall and the vapor-mounted seal may not exceed 21.1 cm2 per meter of tank diameter (1.0 in2 per ft of tank diameter) and the width of any portion of any gap may not exceed 1.27 cm (0.50 in).
3) One end of the metallic shoe shall extend into the stored liquid and the other end shall extend a minimum vertical distance of 61 cm (24 in) above the stored liquid surface.
4) There may be no holes, tears or other openings in the shoe, seal fabric or seal envelope.
NR 440.28(3)(a)1.b.b. The secondary seal shall meet the following requirements:
1) The secondary seal shall be installed above the primary seal so that it completely covers the space between the roof edge and the tank wall except as provided in subd. 1. b. 2).
2) The accumulated area of gaps between the tank wall and the secondary seal used in combination with a metallic shoe or liquid-mounted primary seal may not exceed 21.1 cm2 per meter of tank diameter (1.0 in2 per ft of tank diameter) and the width of any portion of any gap may not exceed 1.27cm (0.50 in). There may be no gaps between the tank wall and the secondary seal used in combination with a vapor-mounted primary seal.
3) There may be no holes, tears or other openings in the seal or seal fabric.
4) The owner or operator is exempted from the requirements for secondary seals and the secondary seal gap criteria when performing gap measurements or inspections of the primary seal.
NR 440.28(3)(a)1.c.c. Each opening in the roof except for automatic bleeder vents and rim space vents shall provide a projection below the liquid surface. Each opening in the roof except for automatic bleeder vents, rim space vents and leg sleeves shall be equipped with a cover, seal or lid which shall be maintained in a closed position at all times (i.e., no visible gap) except when the device is in actual use or as described in subd. 1. d. Automatic bleeder vents shall be closed at all times when the roof is being floated off or is being landed on the roof leg supports. Rim vents shall be set to open when the roof is being floated off the roof legs supports or at the manufacturer’s recommended setting.
NR 440.28(3)(a)1.d.d. Each emergency roof drain shall be provided with a slotted membrane fabric cover that covers at least 90% of the area of the opening.