Wisconsin Administrative Code
Department of Natural Resources
NR 400-499 - Environmental Protection - Air Pollution Control
Chapter NR 440 - Standards of performance for new stationary sources
Subchapter II - Standards of Performance
Section NR 440.445 - Steel plants: electric arc furnaces and argon-oxygen decarburization vessels constructed after August 17, 1983

(a) The provisions of this section are applicable to the following facilities in steel plants that produce carbon, alloy, or specialty steels: electric arc furnaces, argon-oxygen decarburization vessels and dust-handling systems.

(b) The provisions of this section apply to each affected facility identified in par. (a) that commences construction, modification, or reconstruction after August 17, 1983.

(a) "Argon-oxygen decarburization vessel" or "AOD vessel" means any closed-bottom, refractory-lined converter vessel with submerged tuyeres through which gaseous mixtures containing argon and oxygen or nitrogen may be blown into molten steel for further refining.

(am) "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.

(b) "Capture system" means the equipment (including ducts, hoods, fans, dampers, etc.) used to capture or transport particulate matter generated by an electric arc furnace or AOD vessel to the air pollution control device.

(c) "Charge" means the addition of iron and steel scrap or other materials into the top of an electric arc furnace or the addition of molten steel or other materials into the top of an AOD vessel.

(d) "Control device" means the air pollution control equipment used to remove particulate matter from the effluent gas stream generated by an electric arc furnace or AOD vessel.

(e) "Direct-shell evacuation control system" or "DEC system" means a system that maintains a negative pressure within the electric arc furnace above the slag or metal and ducts emissions to the control device.

(f) "Dust-handling system" means equipment used to handle particulate matter collected by the control device for an electric arc furnace or AOD vessel subject to this section. For the purposes of this section the dust-handling system shall consist of the control device dust hoppers, the dust-conveying equipment, any central dust storage equipment, the dust-treating equipment (e.g., pug mill, pelletizer), dust transfer equipment (from storage to truck) and any secondary control devices used with the dust transfer equipment.

(g) "Electric arc furnace" or "EAF" means a furnace that produces molten steel and heats the charge materials with electric arcs from carbon electrodes. For the purposes of this section an EAF shall consist of the furnace shell and roof and the transformer. 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.

(h) "Heat cycle" means the period beginning when scrap is charged to an empty EAF and ending when the EAF tap is completed or beginning when molten steel is charged to an empty AOF vessel and ending when the AOD vessel tap is completed.

(hm) "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.

(i) "Melting" means that phase of steel production cycle during which the iron and steel scrap is heated to the molten state.

(j) "Negative-pressure fabric filter" means a fabric filter with the fans on the downstream side of the filter bags.

(k) "Positive-pressure fabric filter" means a fabric filter with the fans on the upstream side of the filter bags.

(L) "Refining" means the phase of the steel production cycle during which undesirable elements are removed from the molten steel and alloys are added to reach the final metal chemistry.

(m) "Shop" means the building which houses one or more EAF's or AOD vessels.

(n) "Shop opacity" means the arithmetic average of 24 observations of the opacity 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.

(o) "Tap" means the pouring of molten steel from an EAF or AOD vessel.

(om) "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.

(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 EAF or an AOD vessel any gases which:

(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 the dust-handling system any gases that exhibit 10% opacity or greater.

(a) Except as provided under pars. (b) and (c) a continuous monitoring system for the measurement of the opacity of emissions discharged into the atmosphere from the control device(s) shall be installed, calibrated, maintained and operated by the owner or operator subject to the provisions of this section.

(b) No continuous monitoring system is required on any control device serving the dust-handling system.

(c) A continuous monitoring system for the measurement of opacity of emissions discharged into the atmosphere from the control device is not required on 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 are 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, the 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).

(d) A furnace static pressure monitoring device is not required on any EAF equipped with a DEC system if observations of shop opacity are performed by a certified visible emission observer as follows: Shop opacity observations shall be conducted at least once per day when the furnace is operating in the meltdown and refining period. Shop opacity shall be determined as the arithmetic average of 24 or more consecutive 15-second opacity observations of emissions from the shop taken in accordance with Method 9. Shop opacity shall be recorded for any points where visible emissions are observed. Where it is possible to determine that a number of visible emission sites relate to only one incident of visible emissions, only one observation of shop opacity shall be required. In this case, the shop opacity 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.

(e) A bag leak detection system shall be installed and continuously operated on all single-stack fabric filters if the owner or operator elects not to install and operate a continuous opacity monitoring system as provided for under par. (c). In addition, the owner or operator shall meet the visible emissions observation requirements in par. (c). The bag leak detection system shall meet the specifications and requirements of subds. 1. to 8.

(f) For each bag leak detection system installed according to par. (e), the owner or operator shall initiate procedures to determine the cause of all alarms within one hour of an alarm. Except as provided for under par. (g), the cause of the alarm shall be alleviated within 3 hours of the time the alarm occurred by taking whatever corrective actions are necessary. Corrective actions may include the following:

(g) In approving the site-specific monitoring plan required in par. (e) 4., the department may allow owners or operators more than 3 hours to alleviate specific conditions that cause an alarm if the owner or operator identifies the condition that could lead to an alarm in the monitoring plan, adequately explains why it is not feasible to alleviate the condition within 3 hours of the time the alarm occurred, and demonstrates that the requested additional time will ensure alleviation of the condition as expeditiously as practicable.

(a) The owner or operator subject to the provisions of this section shall maintain records of the following information:

(b) Except as provided under 40 CFR 60.274a(e), the owner or operator subject to the provisions of this section shall check and record on a once-per-shift basis the furnace static pressure (if a DEC system is in use, and a furnace static pressure gauge is installed according to par. (f)) and either: check and record the control system fan motor amperes and damper position on a once-per-shift basis; install, calibrate and maintain a monitoring device that continuously records the volumetric flow rate through each separately ducted hood, or install, calibrate and maintain a monitoring device that continuously records the volumetric flow rate at the control device inlet and check and record damper positions on a once-per-shift basis. The monitoring device may be installed in any appropriate location in the exhaust duct such that reproducible flow rate monitoring will result. The flow rate monitoring device shall have an accuracy of ± 10% over its normal operating range and shall be calibrated according to the manufacturer's instructions. The department may require the owner or operator to demonstrate the accuracy of the monitoring device relative to Methods 1 and 2 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17(1).

(c) When the owner or operator of an affected facility is required to demonstrate compliance with the standards under sub. (3) (a) 3., and at any other time that the department may require either: the control system fan motor amperes and all damper positions, the volumetric flow rate through each separately ducted hood, or the volumetric flow rate at the control device inlet and all damper positions shall be determined during all periods in which a hood is operated for the purpose of capturing emissions from the affected facility subject to par. (b). The owner or operator may petition the department for reestablishment of these parameters whenever the owner or operator can demonstrate to the department's satisfaction that the affected facility operating conditions upon which the parameters were previously established are no longer applicable. The values of these parameters as determined during the most recent demonstration of compliance shall be maintained at the appropriate level for each applicable period. Operation at other than baseline values may be subject to the requirements of sub. (7) (c).

(d) Except as provided under 40 CFR 60.274a(e), the owner or operator shall perform monthly operational status inspections of the equipment that is important to the performance of the total capture system, that is, pressure sensors, dampers and damper switches. This inspection shall include observations of the physical appearance of the equipment such as presence of holes in ductwork or hoods, flow constrictions caused by dents or accumulated dust in ductwork and fan erosion. Any deficiencies shall be noted and proper maintenance performed.

Note: Under 40 CFR 60.274a(e), the owner or operator may petition the administrator to approve any alternative to monthly operational status inspections that will provide a continuous record of the operation of each emission capture system.

(f) Except as provided for under 40 CFR 60.274a(e), if emissions during any phase of the heat time are controlled by the use of a DEC system the owner or operator shall install, calibrate and maintain a monitoring device that allows the pressure in the free space inside EAF to be monitored. The pressure shall be recorded as 15-minute integrated averages. The monitoring device may be installed in any appropriate location in the EAF or DEC duct prior to the introduction of ambient air such that reproducible results will be obtained. The pressure monitoring device shall have an accuracy of "5mm of water gauge over its normal operating range and shall be calibrated according to the manufacturer's instruction.

(g) Except as provided in 40 CFR 60.274a(e), when the owner or operator of an EAF controlled by a DEC is required to demonstrate compliance with the standard under sub. (3) (a) 3., and at any other time the department may require, the pressure in the free space inside the furnace shall be determined during the melting and refining periods using the monitoring device required under par. (f). The owner or operator may petition the department for reestablishment of the 15-minute integrated average of the pressure whenever the owner or operator can demonstrate to the department's satisfaction that the EAF operating conditions upon which the pressures were previously established are no longer applicable. The pressure determined during the most recent demonstration of compliance shall be maintained at all times when the EAF is operating in a meltdown and refining period. Operation at higher pressures may be considered by the department to be unacceptable operation and maintenance of the affected facility.

(h) During any performance test required under s. NR 440.08 and for any report thereof required by sub. (6) (f), or to determine compliance with sub. (3) (a) 3., the owner or operator shall monitor the following information for all heats covered by the test:

(a) During performance tests required in s. NR 440.08, the owner or operator may not add gaseous diluents to the effluent gas stream after the fabric in any pressurized fabric filter collector, unless the amount of dilution is separately determined and considered in the determination of emissions.

(b) When emissions from any EAF or AOD vessel are combined with emissions from facilities not subject to the provisions of this section but controlled by a common capture system and control device, the owner or operator shall use either or both of the following procedures during a performance test:

Note: See also sub. (7) (e).

(c) When emission from any EAF or AOD vessel are combined with emissions from facilities not subject to the provisions of this section, the owner or operator shall demonstrate compliance with sub. (3) (a) 3. based on emissions from only the affected facility.

(d) In conducting the performance tests required in s. NR 440.08, the owner or operator shall use as reference methods and procedures the test methods in Appendix A of 40 CFR part 60, incorporated by reference in s. NR 440.17, or other methods and procedures as specified in this subsection, except as provided in s. NR 440.08(2).

(e) The owner or operator shall determine compliance with the particulate matter standards in sub. (3) as follows:

(f) To comply with sub. (5) (c) and (f) to (h), the owner or operator shall obtain the information required in these paragraphs during the particulate matter runs.

(g) Any control device subject to the provisions of this section shall be designed and constructed to allow measurement of emissions using applicable test methods and procedures.

(h) Where emissions from any EAF or AOD vessel are combined with emissions from facilities not subject to the provisions of this section but controlled by a common capture system and control device the owner or operator may use any of the following procedures during a performance test:

(i) Where emissions from any EAF or AOD vessel are combined with emissions from facilities not subject to the provisions of this section determinations of compliance with sub. (3) (a) 3. will only be based upon emissions originating from the affected facility(ies).

(j) Unless the presence of inclement weather makes concurrent testing infeasible the owner or operator shall conduct concurrently the performance tests required under s. NR 440.08 to demonstrate compliance with sub. (3) (a) 1., 2. and 3.

(a) Records of the measurements required in sub. (5) must be retained for at least 2 years following the date of the measurement.

(b) Each owner or operator shall submit a written report of exceedances of the control device opacity to the department semiannually. For the purposes of these reports exceedances are defined as all 6-minute periods during which the average opacity is 3% or greater.

(c) Operation at a furnace static pressure that exceeds the value established under sub. (5) (g) and either operation of control system fan motor amperes at values exceeding " 15% of the value established under sub. (5) (c) or operation at flow rates lower than those established under sub. (5) (c) may be considered by the department to be unacceptable operation and maintenance of the affected facility. Operation at such values shall be reported to the department semiannually.

(e) When the owner or operator of an EAF or AOD is required to demonstrate compliance with the standard under sub. (6) (b) 2. or a combination of sub. (6) (b) 1. and 2., the owner or operator shall obtain approval from the department of the procedure that will be used to determine compliance. Notification of the procedure to be used shall be postmarked at least 30 days prior to the performance test.

(f) For the purpose of this section the owner or operator shall conduct the demonstration of compliance with sub. (3) (a) and furnish the department a written report of the results of the test. This report shall include the following information:

(g) The owner or operator shall maintain records of all shop opacity observations in accordance with sub. (4) (d). All shop opacity observations in excess of the emission limit specified in sub. (3) (a) 3. shall indicate a period of excess emission, and shall be reported to the department semi-annually, according to s. NR 440.07(3).

(h) The owner or operator shall maintain all the following records for each bag leak detection system required under sub. (4) (e):