Chapter NR 463

NR 463.22(20) (20) “Iron and steel foundry” means a facility or portion of a facility that melts one or more of the following: scrap, ingot or other forms of iron and steel, and pours the resulting molten metal into molds to produce final or near final shape products for introduction into commerce. Research and development facilities and operations that only produce non-commercial castings are not included in this definition.

NR 463.22(21) (21) “Metal melting furnace” means a cupola, electric arc furnace or electric induction furnace that converts one or more of the following: scrap, foundry returns and other solid forms of iron and steel to a liquid state. Metal melting furnace does not include a holding furnace, an argon oxygen decarburization vessel or ladle that receives molten metal from a metal melting furnace, and to which metal ingots or other material may be added to adjust the metal chemistry.

NR 463.22(22) (22) “Mold or core making line” means the collection of equipment that is used to mix an aggregate of sand and binder chemicals, form the aggregate into final shape and harden the formed aggregate. A mold or core making line does not include a line for making green sand molds or cores.

NR 463.22(23) (23) “Mold vent” means an intentional opening in a mold through which gases containing pyrolysis products of organic mold and core constituents produced by contact with or proximity to molten metal normally escape the mold during and after metal pouring.

NR 463.22(24) (24) “Monitoring malfunction” means any sudden, infrequent, not reasonably preventable failure of the monitoring system to provide valid data. Monitoring failures that are caused in part by poor maintenance or careless operation are not malfunctions.

NR 463.22(25) (25) “Pouring area” means an area, generally associated with floor and pit molding operations, in which molten metal is brought to each individual mold. Pouring areas include all pouring operations that are not a pouring station.

NR 463.22(26) (26) “Pouring station” means the fixed location to which molds are brought in a continuous or semi-continuous manner to receive molten metal, after which the molds are moved to a cooling area.

NR 463.22(27) (27) “Responsible official” has the meaning given in s. NR 400.02 (136).

NR 463.22(28) (28) “Scrap preheater” means a vessel or other piece of equipment in which metal scrap that is to be used as melting furnace feed is heated to a temperature high enough to eliminate moisture and other volatile impurities or tramp materials by direct flame heating or similar means of heating.

NR 463.22(29) (29) “Scrubber blowdown” means liquor or slurry discharged from a wet scrubber that is either removed as a waste stream or processed to remove impurities or adjust its composition or pH before being returned to the scrubber.

NR 463.22(30) (30) “Work practice standard” means any design, equipment, work practice, operational standard or combination thereof, that is promulgated pursuant to section 112 (h) of the Clean Air Act (42 USC 7412 (h)).

NR 463.22(31) (31) “You” or “your” means the owner or operator of an iron and steel foundry.

NR 463.22 History History: CR 06-110: cr. Register July 2007 No. 619, eff. 8-1-07.

NR 463.23 NR 463.23 Emissions limitations, work practice standards and operation and maintenance requirements.

NR 463.23(1) (1) What emission limits must I meet?

NR 463.23(1)(a) (a) You shall meet each of the following emission limits or standards that applies to you:

NR 463.23(1)(a)1. 1. For each electric arc metal melting furnace, electric induction metal melting furnace or scrap preheater at an existing iron and steel foundry, as described in s. NR 463.21 (3) (c), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for particulate matter (PM) in subd. 1. a. or the limit for total metal HAP in subd. 1. b.:

NR 463.23(1)(a)1.a. a. 0.005 gr/dscf of PM.

NR 463.23(1)(a)1.b. b. 0.0004 gr/dscf of total metal HAP.

NR 463.23(1)(a)2. 2. For each cupola metal melting furnace at an existing iron and steel foundry, as described in s. NR 463.21 (3) (c), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for PM in subd. 2. a. or the limit for total metal HAP in subd. 2. b.:

NR 463.23(1)(a)2.a. a. 0.006 gr/dscf of PM.

NR 463.23(1)(a)2.b. b. 0.0005 gr/dscf of total metal HAP.

NR 463.23(1)(a)3. 3. For each cupola metal melting furnace or electric arc metal melting furnace at a new iron and steel foundry, as described in s. NR 463.21 (3) (d), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for PM in subd. 3. a. or, alternatively, the limit for total metal HAP in subd. 3. b.:

NR 463.23(1)(a)3.a. a. 0.002 gr/dscf of PM.

NR 463.23(1)(a)3.b. b. 0.0002 gr/dscf of total metal HAP.

NR 463.23(1)(a)4. 4. For each electric induction metal melting furnace or scrap preheater at a new iron and steel foundry, as described in s. NR 463.21 (3) (d), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for PM in subd. 4. a. or, alternatively, the limit for total metal HAP in subd. 4. b.:

NR 463.23(1)(a)4.a. a. 0.001 gr/dscf of PM.

NR 463.23(1)(a)4.b. b. 0.00008 gr/dscf of total metal HAP.

NR 463.23(1)(a)5. 5. For each pouring station at an existing iron and steel foundry, as described in s. NR 463.21 (3) (c), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for PM in subd. 5. a. or, alternatively, the limit for total metal HAP in subd. 5. b.:

NR 463.23(1)(a)5.a. a. 0.010 gr/dscf of PM.

NR 463.23(1)(a)5.b. b. 0.0008 gr/dscf of total metal HAP.

NR 463.23(1)(a)6. 6. For each pouring area or pouring station at a new iron and steel foundry, as described in s. NR 463.21 (3) (d), you may not discharge emissions through a conveyance to the atmosphere that exceed either the limit for PM in subd. 6. a. or, alternatively, the limit for total metal HAP in subd. 6. b.:

NR 463.23(1)(a)6.a. a. 0.002 gr/dscf of PM.

NR 463.23(1)(a)6.b. b. 0.0002 gr/dscf of total metal HAP.

NR 463.23(1)(a)7. 7. For each building or structure housing any emissions source at the iron and steel foundry, you may not discharge any fugitive emissions to the atmosphere that exhibit opacity greater than 20% averaged over 6 minutes except for one 6-minute average per hour that does not exceed 27% opacity.

NR 463.23(1)(a)8. 8. For each cupola metal melting furnace at a new or existing iron and steel foundry, you may not discharge emissions of volatile organic hazardous air pollutants (VOHAP) through a conveyance to the atmosphere that exceed 20 parts per million by volume (ppmv) corrected to 10% oxygen.

NR 463.23(1)(a)9. 9. As an alternative to the work practice standard in sub. (2) (e) for a scrap preheater at an existing iron and steel foundry or in sub. (2) (f) for a scrap preheater at a new iron and steel foundry, as described in s. NR 463.21 (3) (d), you may not discharge emissions of VOHAP through a conveyance to the atmosphere that exceed 20 ppmv.

NR 463.23(1)(a)10. 10. For one or more automated conveyor and pallet cooling lines that use a sand mold system, or one or more automated shakeout lines that use a sand mold system, at a new iron and steel foundry, as described in s. NR 463.21 (3) (d), you may not discharge emissions of VOHAP through a conveyance to the atmosphere that exceed a flow-weighted average of 20 ppmv.

NR 463.23(1)(a)11. 11. For each triethylamine (TEA) cold box mold or core making line at a new or existing iron and steel foundry, you shall meet either the emission limit in subd. 11. a. or the emission standard in subd. 11. b.:

NR 463.23(1)(a)11.a. a. You may not discharge emissions of TEA through a conveyance to the atmosphere that exceed 1 ppmv, as determined when scrubbing with fresh acid solution.

NR 463.23(1)(a)11.b. b. You shall reduce emissions of TEA from each TEA cold box mold or core making line by at least 99%, as determined when scrubbing with fresh acid solution.

NR 463.23(1)(b) (b) You shall meet each of the following operating limits that applies to you:

NR 463.23(1)(b)1. 1. You shall install, operate and maintain a capture and collection system for all emission sources subject to an emission limit or standard for VOHAP or TEA in par. (a) 8. to 11. in accordance with both of the following:

NR 463.23(1)(b)1.a. a. Each capture and collection system shall meet accepted engineering standards, such as those published by the American Conference of Governmental Industrial Hygienists.

NR 463.23 Note Note: Publications of the American Conference of Governmental Industrial Hygienists may be obtained at:

NR 463.23 Note American Conference of Governmental Industrial Hygienists
1330 Kemper Meadow Drive
Cincinnati, Ohio 45240
[phone]
[e-mail]
www.acgih.org

NR 463.23(1)(b)1.b. b. You shall operate each capture system at or above the lowest value or settings established as operating limits in your operation and maintenance plan.

NR 463.23(1)(b)2. 2. You shall operate each wet scrubber applied to emissions from a metal melting furnace, scrap preheater, pouring area or pouring station subject to an emission limit for PM or total metal HAP in par. (a) 1. to 6. to insure that the 3-hour average pressure drop and scrubber water flow rate does not fall below the minimum levels established during the initial or subsequent performance test.

NR 463.23(1)(b)3. 3. You shall operate each combustion device applied to emissions from a cupola metal melting furnace subject to the emission limit for VOHAP in par. (a) 8. to insure that the 15-minute average combustion zone temperature does not fall below 1,300ºF. Periods when the cupola is off blast and for 15 minutes after going on blast from an off blast condition are not included in the 15-minute average.

NR 463.23(1)(b)4. 4. You shall operate each combustion device applied to emissions from a scrap preheater subject to the emission limit for VOHAP in par. (a) 9. or from a TEA cold box mold or core making line subject to the emission limit for TEA in par. (a) 11. to insure that the 3-hour average combustion zone temperature does not fall below the minimum level established during the initial or subsequent performance test.

NR 463.23(1)(b)5. 5. You shall operate each wet acid scrubber applied to emissions from a TEA cold box mold or core making line subject to the emission limit for TEA in par. (a) 11. to insure both of the following:

NR 463.23(1)(b)5.a. a. The 3-hour average scrubbing liquid flow rate does not fall below the minimum level established during the initial or subsequent performance test.

NR 463.23(1)(b)5.b. b. The 3-hour average pH of the scrubber blowdown, as measured by a continuous parameter monitoring system (CPMS), does not exceed 4.5 or the pH of the scrubber blowdown, as measured once every 8 hours during process operations, does not exceed 4.5.

NR 463.23(1)(c) (c) If you use a control device other than a baghouse, wet scrubber, wet acid scrubber or combustion device, you shall prepare and submit a monitoring plan. The monitoring plan is subject to approval by the department and shall contain all of the following:

NR 463.23(1)(c)1. 1. A description of the device.

NR 463.23(1)(c)2. 2. Test results collected in accordance with s. NR 463.25 (3) verifying the performance of the device for reducing emissions of PM, total metal HAP, VOHAP or TEA to the levels required by this subchapter.

NR 463.23(1)(c)3. 3. A copy of the operation and maintenance plan required by sub. (3) (b).

NR 463.23(1)(c)4. 4. A list of appropriate operating parameters that will be monitored to maintain continuous compliance with the applicable emissions limitations.

NR 463.23(1)(c)5. 5. Operating parameter limits based on monitoring data collected during the performance test.

NR 463.23(2) (2) What work practice standards must I meet?

NR 463.23(2)(a) (a) For each segregated scrap storage area, bin or pile, you shall either comply with the certification requirements in par. (b) or prepare and implement a plan for the selection and inspection of scrap according to the requirements in par. (c). You may have certain scrap subject to par. (b) and other scrap subject to par. (c) at your facility, provided the scrap remains segregated until being aggregated to make up the charge for the furnace.

NR 463.23(2)(b) (b) If you elect to meet this paragraph as allowed under par. (a), you shall prepare, and operate at all times according to, a written certification that the foundry purchases and uses only metal ingots, pig iron, slitter or other materials that do not include post-consumer automotive body scrap, post-consumer engine blocks, post-consumer oil filters, oily turnings, lead components, mercury switches, plastics or free organic liquids, as defined in s. NR 463.22 (16). Any post-consumer engine blocks, post-consumer oil filters or oily turnings that are processed and cleaned, to the extent practicable, such that the materials do not include lead components, mercury switches, plastics or free organic liquids may be included in this certification.

NR 463.23(2)(c) (c) If you elect to meet this paragraph as allowed under par. (a), you shall prepare and operate at all times according to a written plan for the selection and inspection of iron and steel scrap to minimize, to the extent practicable, the amount of organics and HAP metals in the charge materials used by the iron and steel foundry. This scrap selection and inspection plan is subject to approval by the department. You shall keep a copy of the plan onsite and readily available to all plant personnel with materials acquisition or inspection duties. You shall provide a copy of the material specifications to each of your scrap vendors. Each plan shall include all of the following information:

NR 463.23(2)(c)1. 1. A materials acquisition program to limit organic contaminants according to the following requirements as applicable:

NR 463.23(2)(c)1.a. a. For scrap charged to a scrap preheater, electric arc metal melting furnace or electric induction metal melting furnaces, specifications for scrap materials to be depleted, to the extent practicable, of the presence of used oil filters, plastic parts and organic liquids, and a program to ensure the scrap materials are drained of free liquids.

NR 463.23(2)(c)1.b. b. For scrap charged to a cupola metal melting furnace, specifications for scrap materials to be depleted, to the extent practicable, of the presence of plastic, and a program to ensure the scrap materials are drained of free liquids.

NR 463.23(2)(c)2. 2. A materials acquisition program specifying that the scrap supplier remove accessible mercury switches from the trunks and hoods of any automotive bodies contained in the scrap and remove accessible lead components such as batteries and wheel weights. You shall obtain and maintain onsite a copy of the procedures used by the scrap supplier for either removing accessible mercury switches or for purchasing automobile bodies that have had mercury switches removed, as applicable.

NR 463.23(2)(c)3. 3. Procedures for visual inspection of a representative portion, but not less than 10%, of all incoming scrap shipments to ensure the materials meet the specifications. The inspection procedures shall do all of the following:

NR 463.23(2)(c)3.a. a. Identify the locations where inspections are to be performed for each type of shipment. Inspections may be performed at the scrap supplier’s facility. The selected locations shall provide a reasonable vantage point, considering worker safety, for visual inspection.

NR 463.23(2)(c)3.b. b. Include recordkeeping requirements for the documentation of each visual inspection including the results.

NR 463.23(2)(c)3.c. c. Include provisions for rejecting or returning entire or partial scrap shipments that do not meet specifications and limiting purchases from vendors whose shipments fail to meet specifications for more than 3 inspections in one calendar year.

NR 463.23(2)(c)3.d. d. If the inspections are performed at the scrap supplier’s facility, include an explanation of how the periodic inspections ensure that not less than 10% of scrap purchased from each supplier is subject to inspection.

NR 463.23(2)(d) (d) For each furan warm box mold or core making line in a new or existing iron and steel foundry, you shall use a binder chemical formulation that does not contain methanol as a specific ingredient of the catalyst formulation as determined by the material safety data sheet. This requirement does not apply to the resin portion of the binder system.

NR 463.23(2)(e) (e) For each scrap preheater at an existing iron and steel foundry, you shall meet either of the following requirements, or, as an alternative, you may meet the VOHAP emissions limit in sub. (1) (a) 9.:

NR 463.23(2)(e)1. 1. You shall install, operate and maintain a gas-fired preheater where the flame directly contacts the scrap charged.

NR 463.23(2)(e)2. 2. You shall charge only material that is subject to and in compliance with the scrap certification requirement in par. (b).

NR 463.23(2)(f) (f) For each scrap preheater at a new iron and steel foundry, you shall charge only material that is subject to, and in compliance with, the scrap certification requirement in par. (b). As an alternative to this requirement, you may meet the VOHAP emissions limit in sub. (1) (a) 9.

NR 463.23(3) (3) What are my operation and maintenance requirements?

NR 463.23(3)(a) (a) As required by s. NR 460.05 (4) (a) 1., you shall always operate and maintain your iron and steel foundry, including air pollution control and monitoring equipment, in a manner consistent with good air pollution control practices for minimizing emissions at least to the levels required by this subchapter.

NR 463.23(3)(b) (b) You shall prepare, and operate at all times according to, a written operation and maintenance plan for each capture and collection system and control device for an emissions source subject to an emissions limit in sub. (1) (a). Your operation and maintenance plan shall also include procedures for igniting gases from mold vents in pouring areas and pouring stations that use a sand mold system. The operation and maintenance plan is subject to approval by the department and shall contain all of the following elements:

NR 463.23(3)(b)1. 1. Monthly inspections of the equipment that is important to the performance of the total capture system, such as pressure sensors, dampers and damper switches. The inspections shall include observations of the physical appearance of the equipment, such as the presence of holes in the ductwork or hoods, flow constrictions caused by dents or accumulated dust in the ductwork and fan erosion. The operation and maintenance plan shall also include requirements to repair the defect or deficiency as soon as practicable.

NR 463.23(3)(b)2. 2. Operating limits for each capture system for an emissions source subject to an emissions limit or standard for VOHAP or TEA in sub. (1) (a) 8. to 11. You shall establish the operating limits according to all of the following requirements:

NR 463.23(3)(b)2.a. a. You shall select operating limit parameters appropriate for the capture system design that are representative and reliable indicators of the performance of the capture system. At a minimum, you shall use appropriate operating limit parameters that indicate the level of the ventilation draft and damper position settings for the capture system when operating to collect emissions, including revised settings for seasonal variations. Appropriate operating limit parameters for ventilation draft include volumetric flow rate through each separately ducted hood, total volumetric flow rate at the inlet to the control device to which the capture system is vented, fan motor amperage or static pressure. Any parameter for damper position setting may be used that indicates the duct damper position related to the fully open setting.

NR 463.23(3)(b)2.b. b. For each operating limit parameter selected in subd. 2. a., you shall designate the value or setting for the parameter at which the capture system operates during the process operation. If your operation allows for more than one process to be operating simultaneously, you shall designate the value or setting for the parameter at which the capture system operates during each possible configuration that you may operate, for example the operating limits with one furnace melting or 2 melting, as applicable to your plant.

NR 463.23(3)(b)2.c. c. You shall include documentation in your plan to support your selection of the operating limits established for your capture system. This documentation shall include a description of the capture system design, a description of the capture system operating during production, a description of each selected operating limit parameter, a rationale for why you chose the parameter, a description of the method used to monitor the parameter according to the requirements of s. NR 463.26 (1) (a) and the data used to establish the value or setting for the parameter for each of your process configurations.

NR 463.23(3)(b)3. 3. A preventive maintenance plan for each control device, including a preventive maintenance schedule that is consistent with the manufacturer’s instructions for routine and long-term maintenance.

NR 463.23(3)(b)4. 4. A site-specific monitoring plan for each bag leak detection system. For each bag leak detection system that operates on the triboelectric effect, the monitoring plan shall be consistent with the recommendations contained in the U.S. Environmental Protection Agency guidance document “Fabric Filter Bag Leak Detection Guidance’’, EPA-454/R-98-015, incorporated by reference in s. NR 484.06 (4) (c). The owner or operator shall operate and maintain the bag leak detection system according to the site-specific monitoring plan at all times. The baghouse monitoring plan is subject to approval by the department and shall address all of the following items:

NR 463.23(3)(b)4.a. a. Installation of the bag leak detection system.

NR 463.23(3)(b)4.b. b. Initial and periodic adjustment of the bag leak detection system, including how the alarm set-point will be established.