NR 440.28(4)(a)1.1. The owner or operator of each storage vessel to which this section applies which has an external floating roof shall meet the following requirements: NR 440.28(4)(a)1.a.a. Determine the gap areas and maximum gap widths between the primary seal and the storage vessel wall, and between the secondary seal and the storage vessel wall according to the following frequency: 1) For primary seals, gap measurements shall be performed within 60 days of the initial fill with petroleum liquid and at least once every 5 years thereafter. All primary seal inspections or gap measurements which require the removal or dislodging of the secondary seal shall be accomplished as rapidly as possible and the secondary seal shall be replaced as soon as possible.
2) For secondary seals, gap measurements shall be performed within 60 days of the initial fill with petroleum liquid and at least once every year thereafter.
3) If any storage vessel is out of service for a period of one year or more, subsequent refilling with petroleum liquid shall be considered initial fill for the purposes of subd. 1. a. 1) and 2).
4) Keep records of each gap measurement at the plant for a period of at least 2 years following the date of measurement. Each record shall identify the vessel on which the measurement was performed and shall contain the date of the seal gap measurement, the raw data obtained in the measurement process required by subd. 1. b. and the calculation required by subd. 1. c.
5) If either the seal gap calculated in accord with subd. 1. c. or the measured maximum seal gap exceeds the limitations specified by sub. (3), a report shall be furnished to the department within 60 days of the date of the measurement. The report shall identify the vessel and list each reason why the vessel did not meet the specifications of sub. (3). the report shall also describe the actions necessary to bring the storage vessel into compliance with the specifications of sub. (3).
NR 440.28(4)(a)1.b.b. Determine gap widths in the primary and secondary seals individually by the following procedures: 1) Measure seal gaps, if any, at one or more floating roof levels when the roof is floating off the roof leg supports.
2) Measure seal gaps around the entire circumference of the tank in each place where a 1/8″ diameter uniform probe passes freely (without forcing or binding against seal) between the seal and the tank wall and measure the circumferential distance of each such location.
3) The total surface area of each gap described in subd. 1. b. 2) shall be determined by using probes of various widths to accurately measure the actual distance from the tank wall to the seal and multiplying each such width by its respective circumferential distance.
NR 440.28(4)(a)1.c.c. Add the gap surface area of each gap location for the primary seal and the secondary seal individually. Divide the sum for each seal by the nominal diameter of the tank and compare each ratio to the appropriate ratio in the standard in sub. (3) (a) 1. a. and b. NR 440.28(4)(a)1.d.d. Provide the department 30 days prior notice of the gap measurement to afford it the opportunity to have an observer present. NR 440.28(4)(a)2.2. The owner or operator of each storage vessel to which this section applies which has a vapor recovery and return or disposal system shall provide the following information to the department on or before the date on which construction of the storage vessel commences: NR 440.28(4)(a)2.a.a. Emission data, if available, for a similar vapor recovery and return or disposal system used on the same type of storage vessel, which can be used to determine the efficiency of the system. A complete description of the emission measurement method used shall be included. NR 440.28(4)(a)2.b.b. The manufacturer’s design specifications and estimated emission reduction capability of the system. NR 440.28(4)(a)2.d.d. Any other information which will be useful to the department in evaluating the effectiveness of the system in reducing VOC emissions. NR 440.28(5)(a)(a) If, in the administrator’s judgment, an alternative means of emission limitation will achieve a reduction in emissions at least equivalent to the reduction in emissions achieved by any requirements in sub. (3), the administrator will publish in the federal register a notice permitting the use of the alternative means for purpose of compliance with that requirement. NR 440.28(5)(b)(b) Any notice under par. (a) will be published only after notice and an opportunity for a hearing. NR 440.28(5)(c)(c) Any person seeking permission to use an alternative means of emission limitation under this subsection shall submit to the administrator a written application including: NR 440.28(5)(c)1.1. An actual emissions test that uses a full-sized or scale-model storage vessel that accurately collects and measures all VOC emissions from a given control device and that accurately simulates wind and accounts for other emission variables such as temperature and barometric pressure. NR 440.28(5)(c)2.2. An engineering evaluation that the administrator determines is an accurate method of determining equivalence. NR 440.28(5)(d)(d) The administrator may condition the permission on requirements that may be necessary to ensure operation and maintenance to achieve the same emissions reduction as specified in sub. (3). NR 440.28(5)(e)(e) The primary vapor-mounted seal in the “Volume-Maximizing Seal” manufactured by R.F.I. Services Corporation is approved as equivalent to the vapor-mounted seal required by sub. (3) (a) 1. a. and shall meet the gap criteria specified in sub. (3) (a) 1. a. 2). There may be no gaps between the tank wall and any secondary seal used in conjunction with the primary seal in the “Volume-Maximizing Seal.” NR 440.28(6)(a)(a) Except as provided in par. (d), the owner or operator subject to this section shall maintain a record of the petroleum liquid stored, the period of storage, and the maximum true vapor pressure of that liquid during the respective storage period. NR 440.28(6)(b)(b) Available data on the typical Reid vapor pressure and the maximum expected storage temperature of the stored product may be used to determine the maximum true vapor pressure from nomographs contained in API Publication 2517, incorporated by reference in s. NR 440.17, unless the department specifically requests that the liquid be sampled, the actual storage temperature determined, and the Reid vapor pressure determined from samples.