NR 665.1085(5)(c)4.a.a. Prior to each visual inspection of an internal floating roof in a tank that has been emptied and degassed, prepare and send written notification so that the department receives it at least 30 calendar days before refilling the tank, except when an inspection is not planned as provided for in subd. 4. b. NR 665.1085(5)(c)4.b.b. When a visual inspection is not planned and the owner or operator could not have known about the inspection 30 calendar days before refilling the tank, notify the department as soon as possible, but no later than 7 calendar days before refilling the tank. Make this notification by telephone and immediately follow with a written explanation for why the inspection is unplanned. Alternatively, send written notification, including the explanation for the unplanned inspection, so that the department receives it at least 7 calendar days before refilling the tank. NR 665.1085(5)(d)(d) Safety devices, as defined in s. NR 665.1081, may be installed and operated as necessary on any tank complying with this subsection. NR 665.1085(6)(6) The owner or operator who controls air pollutant emissions from a tank using an external floating roof shall meet pars. (a) to (c). NR 665.1085(6)(a)(a) Design the external floating roof according to all of the following requirements: NR 665.1085(6)(a)1.1. Design the external floating roof to float on the liquid surface except when the floating roof must be supported by the leg supports. NR 665.1085(6)(a)2.2. Equip the floating roof with 2 continuous seals, one above the other, between the wall of the tank and the roof edge. The lower seal is referred to as the primary seal, and the upper seal is referred to as the secondary seal. NR 665.1085(6)(a)2.a.a. The primary seal shall be a liquid-mounted seal or a metallic shoe seal, as defined in s. NR 665.1081. The total area of the gaps between the tank wall and the primary seal may not exceed 212 square centimeters (cm2) per meter of tank diameter, and the width of any portion of these gaps may not exceed 3.8 centimeters (cm). If a metallic shoe seal is used for the primary seal, design the metallic shoe seal so that one end extends into the liquid in the tank and the other end extends a vertical distance of at least 61 centimeters above the liquid surface. NR 665.1085(6)(a)2.b.b. Mount the secondary seal above the primary seal and cover the annular space between the floating roof and the wall of the tank. The total area of the gaps between the tank wall and the secondary seal may not exceed 21.2 square centimeters (cm2) per meter of tank diameter, and the width of any portion of these gaps may not exceed 1.3 centimeters (cm). NR 665.1085(6)(a)3.3. The external floating roof shall meet all of the following specifications: NR 665.1085(6)(a)3.a.a. Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in a non-contact external floating roof shall project below the liquid surface. NR 665.1085(6)(a)3.b.b. Except for automatic bleeder vents, rim space vents, roof drains and leg sleeves, equip each opening in the roof with a gasketed cover, seal or lid. NR 665.1085(6)(a)3.c.c. Equip each access hatch and each gauge float well with a cover designed to be bolted or fastened when the cover is secured in the closed position. NR 665.1085(6)(a)3.e.e. Equip each roof drain that empties into the liquid managed in the tank with a slotted membrane fabric cover that covers at least 90 percent of the area of the opening. NR 665.1085(6)(a)3.f.f. Equip each unslotted and slotted guide pole well with a gasketed sliding cover or a flexible fabric sleeve seal. NR 665.1085(6)(a)3.h.h. Equip each slotted guide pole with a gasketed float or other device which closes off the liquid surface from the atmosphere. NR 665.1085(6)(b)(b) Operate the tank according to all of the following requirements: NR 665.1085(6)(b)1.1. When the floating roof is resting on the leg supports, the process of filling, emptying or refilling shall be continuous and shall be completed as soon as practical. NR 665.1085(6)(b)2.2. Except for automatic bleeder vents, rim space vents, roof drains and leg sleeves, secure and maintain each opening in the roof in a closed position at all times except when the closure device must be open for access. NR 665.1085(6)(b)3.3. Bolt or fasten covers on each access hatch and each gauge float well when secured in the closed position. NR 665.1085(6)(b)4.4. Set closed automatic bleeder vents at all times when the roof is floating, except when the roof is being floated off or is being landed on the leg supports. NR 665.1085(6)(b)5.5. Set to open rim space vents only at those times that the roof is being floated off the roof leg supports or when the pressure beneath the rim seal exceeds the manufacturer’s recommended setting. NR 665.1085(6)(b)6.6. Secure the cap on the end of each unslotted guide pole in the closed position at all times except when measuring the level of the liquid in the tank or collecting samples of the liquid. NR 665.1085(6)(b)7.7. Secure the cover on each gauge hatch or sample well in the closed position at all times except when the hatch or well must be opened for access.