NR 664.1084(6)(c)2.b.b. Perform an initial inspection of the external floating roof and its closure devices on or before the date that the tank becomes subject to this section. Thereafter, perform the inspections at least once every year except for the special conditions provided for in sub. (12). NR 664.1084(6)(c)3.3. Prior to each inspection required by subd. 1. or 2., notify the department in advance of each inspection to provide the department with the opportunity to have an observer present during the inspection. Notify the department of the date and location of the inspection as follows: NR 664.1084(6)(c)3.a.a. Prior to each inspection to measure external floating roof seal gaps as required under subd. 1., prepare and send written notification so that the department receives it at least 30 calendar days before the date the measurements are scheduled to be performed. NR 664.1084(6)(c)3.b.b. Prior to each visual inspection of an external 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. 3. c. NR 664.1084(6)(c)3.c.c. 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. This notification may be made by telephone and immediately followed by a written explanation for why the inspection is unplanned. Alternatively, written notification, including the explanation for the unplanned inspection, may be sent so that the department receives it at least 7 calendar days before refilling the tank. NR 664.1084(6)(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 664.1084(7)(7) The owner or operator who controls air pollutant emissions from a tank by venting the tank to a control device shall meet all of the following requirements: NR 664.1084(7)(a)(a) Cover the tank with a fixed roof and vent the tank directly through a closed-vent system to a control device according to all of the following requirements: NR 664.1084(7)(a)1.1. Design the fixed roof and its closure devices to form a continuous barrier over the entire surface area of the liquid in the tank. NR 664.1084(7)(a)2.2. Equip each opening in the fixed roof not vented to the control device with a closure device. If the pressure in the vapor headspace underneath the fixed roof is less than atmospheric pressure when the control device is operating, design the closure devices to operate such that when the closure device is secured in the closed position there are no visible cracks, holes, gaps or other open spaces in the closure device or between the perimeter of the cover opening and the closure device. If the pressure in the vapor headspace underneath the fixed roof is equal to or greater than atmospheric pressure when the control device is operating, design the closure device to operate with no detectable organic emissions. NR 664.1084(7)(a)3.3. Make the fixed roof and its closure devices of suitable materials that will minimize exposure of the hazardous waste to the atmosphere, to the extent practical, and will maintain the integrity of the fixed roof and closure devices throughout their intended service life. Factors to consider when selecting the materials for and designing the fixed roof and closure devices shall include organic vapor permeability, the effects of any contact with the liquid and its vapor managed in the tank, the effects of outdoor exposure to wind, moisture and sunlight and the operating practices used for the tank on which the fixed roof is installed. NR 664.1084(7)(b)(b) Whenever a hazardous waste is in the tank, install the fixed roof with each closure device secured in the closed position and the vapor headspace underneath the fixed roof vented to the control device except as follows: NR 664.1084(7)(b)1.1. Venting to the control device is not required, and opening of closure devices or removal of the fixed roof is allowed at the following times: NR 664.1084(7)(b)1.a.a. To provide access to the tank for performing routine inspection, maintenance or other activities needed for normal operations. Examples of those activities include those times when a worker needs to open a port to sample liquid in the tank or when a worker needs to open a hatch to maintain or repair equipment. After completing the activity, promptly secure the closure device in the closed position or reinstall the cover, as applicable, to the tank. NR 664.1084(7)(b)2.2. Opening of a safety device, as defined in s. NR 665.1081, is allowed at any time conditions require doing so to avoid an unsafe condition. NR 664.1084(7)(c)(c) Inspect and monitor the air emission control equipment according to all of the following procedures: NR 664.1084(7)(c)1.1. Visually inspect the fixed roof and its closure devices to check for defects that could result in air pollutant emissions. Defects include, but are not limited to, visible cracks, holes or gaps in the roof sections or between the roof and the tank wall, broken, cracked or otherwise damaged seals or gaskets on closure devices and broken or missing hatches, access covers, caps or other closure devices. NR 664.1084(7)(c)3.3. Perform an initial inspection of the air emission control equipment on or before the date that the tank becomes subject to this section. Thereafter, perform the inspections at least once every year except for the special conditions provided for in sub. (12). NR 664.1084(8)(8) The owner or operator who controls air pollutant emissions by using a pressure tank shall meet all of the following requirements: NR 664.1084(8)(a)(a) Design the tank to not vent to the atmosphere as a result of compression of the vapor headspace in the tank during filling of the tank to its design capacity. NR 664.1084(8)(b)(b) Equip all tank openings with closure devices designed to operate with no detectable organic emissions determined using the procedure in s. NR 664.1083 (4). NR 664.1084(8)(c)(c) Whenever hazardous waste is in the tank, operate the tank as a closed system that does not vent to the atmosphere except under any of the following conditions: