NR 440.44(2)(a)(a) “Bag leak detection system” means a system that is capable of continuously monitoring relative particulate matter (dust) loadings in the exhaust of a baghouse to detect bag leaks and other conditions that result in increases in particulate loadings. A bag leak detection system includes an instrument that operates on triboelectric, electrodynamic, light scattering, light transmittance, or other effect to continuously monitor relative particulate matter loadings. NR 440.44(2)(am)(am) “Capture system” means the equipment (including ducts, hoods, fans, dampers, etc.) used to capture or transport particulate matter generated by an EAF to the air pollution control device. NR 440.44(2)(b)(b) “Charge” means the addition of iron and steel scrap or other materials into the top of an electric arc furnace. NR 440.44(2)(c)(c) “Charging period” means the time period commencing at the moment an EAF starts to open and ending either 3 minutes after the EAF roof is returned to its closed position or 6 minutes after commencement of opening of the roof, whichever is longer. NR 440.44(2)(d)(d) “Control device” means the air pollution control equipment used to remove particulate matter generated by one or more EAFs from the effluent gas stream. NR 440.44(2)(e)(e) “Direct shell evacuation control system” or “DEC system” means any system that maintains a negative pressure within the EAF above the slag or metal and ducts these emissions to the control device. NR 440.44(2)(f)(f) “Dust-handling equipment” means any equipment used to handle particulate matter collected by the control device and located at or near the control device for an EAF subject to this section. NR 440.44(2)(g)(g) “Electric arc furnace” or “EAF” means any furnace that produces molten steel and heats the charge materials with electric arcs from carbon electrodes. Furnaces that continuously feed direct-reduced iron ore pellets as the primary source of iron are not affected facilities within the scope of this definition. NR 440.44(2)(h)(h) “Heat time” means the period commencing when scrap is charged to an empty EAF and terminating when the EAF tap is completed. NR 440.44(2)(i)(i) “Meltdown and refining” means that phase of the steel production cycle when charge material is melted and undesirable elements are removed from the metal. NR 440.44(2)(j)(j) “Meltdown and refining period” means the time period commencing at the termination of the initial charging period and ending at the initiation of the tapping period, excluding any intermediate charging periods and times when power to the EAF is off. NR 440.44(2)(k)(k) “Shop” means the building which houses one or more EAFs. NR 440.44(2)(L)(L) “Shop opacity” means the arithmetic average of 24 or more opacity observations of emissions from the shop taken in accordance with Method 9 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17, for the applicable time periods. NR 440.44(2)(n)(n) “Tapping period” means the time period commencing at the moment an EAF begins to pour molten steel and ending either 3 minutes after steel ceases to flow from an EAF, or 6 minutes after steel begins to flow, whichever is longer. NR 440.44(3)(a)(a) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from an electric arc furnace any gases which: NR 440.44(3)(a)1.1. Exit from a control device and contain particulate matter in excess of 12 mg/dscm (0.0052 gr/dscf). NR 440.44(3)(a)3.3. Exit from a shop and, due solely to operations of any EAFs, exhibit 6% opacity or greater except: NR 440.44(3)(a)3.c.c. The shop opacity standards of this subdivision shall apply only during periods when the monitoring parameter limits specified in sub. (5) (b) are being established according to sub. (5) (c) and (g), unless the owner or operator elects to perform daily shop opacity observations in lieu of furnace static pressure monitoring as provided for under sub. (4) (d). NR 440.44(3)(a)3.d.d. Where the capture system is operated such that the roof of the shop is closed during the charge and the tap, and emissions to the atmosphere are prevented until the roof is opened after completion of the charge or tap, the shop opacity standards of this subdivision apply when the roof is opened and continue to apply for the length of time defined by the charging or tapping periods, or both. NR 440.44(3)(b)(b) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from dust-handling equipment any gases which exhibit 10% opacity or greater. NR 440.44(4)(a)(a) A continuous monitoring system for the measurement of the opacity of emissions discharged into the atmosphere from control devices shall be installed, calibrated, maintained and operated by the owner or operator subject to the provisions of this section. NR 440.44(4)(b)(b) For the purpose of reports under s. NR 440.07 (3), all 6-minute periods during which the average opacity is 3% or greater shall indicate a period of excess emission, and shall be reported to the department semi-annually. NR 440.44(4)(c)(c) A continuous monitoring system for the measurement of the opacity of emissions discharged into the atmosphere from the control device is not required on any modular, multiple-stack, negative-pressure or positive-pressure fabric filter if observations of the opacity of the visible emissions from the control device are performed by a certified visible emissions observer; or on any single-stack fabric filter if visible emissions from the control device are performed by a certified visible emission observer and the owner installs and continuously operates a bag leak detection system according to par. (e). Visible emission observations shall be conducted at least once per day for at least 3 6-minute periods when the furnace is operating in the melting and refining period. All visible emissions observations shall be conducted in accordance with Method 9. If visible emissions occur from more than one point, the opacity shall be recorded for any point where visible emissions are observed. Where it is possible to determine that a number of visible emission sites relate to only one incident of the visible emission, only one set of 3 6-minute observations will be required. In that case, Method 9 observations shall be made for the site of highest opacity that directly relates to the cause, or location, of visible emissions observed during a single incident. Records shall be maintained of any 6-minute average that is in excess of the emission limit specified in sub. (3) (a).