Technical Support Document for Draft Air Emission Permit No

Transcription

1 Technical Support Document for Draft Air Permit No This technical support document (TSD) is intended for all parties interested in the draft permit and to meet the requirements that have been set forth by the federal and state regulations (40 CFR 70.7(a)(5) and Minn. R , subp. 1). The purpose of this document is to provide the legal and factual justification for each applicable requirement or policy decision considered in the preliminary determination to issue the draft permit. 1. General information 1.1 Applicant and stationary source location Table 1. Applicant and source address Applicant/Address Steven Metzenbauer 1058 E Mark St Winona, Minnesota Contact: Steven Metzenbauer Phone: Stationary source/address (SIC Code: 3321) Badger Foundry Co 1058 E Mark St Winona MN Facility description Badger Foundry operates a gray iron foundry with one cupola and electric melt furnace, supporting machine operations, and natural gas combustion units. The foundry is currently dedicated to making gray iron and ductile iron castings. Badger Foundry uses primarily green sand molds and phenolic urethane cores. In general, the major emissions from foundries are particulate matter (PM), including particulate matter less than ten microns (PM 10) and particulate matter less than 2.5 microns (PM 2.5), and volatile organic compounds (VOC). Particulate matter is generated from virtually all of the operations at a foundry. VOCs are generated when the molten metal comes in contact with the green sand molds and the cores, and when mold and core sand is mixed with binders. The PM emissions from the blasting cabinets that clean the castings are controlled by baghouses. PM emissions from sand handling are controlled by the moisture content of the sand. The PM from the shake-out area and the mold sand muller are controlled by baghouses. PM emissions from the cupola are controlled by a venturi scrubber and VOC emissions from the cupola are controlled by an afterburner. The primary sources of HAP emissions are the mixing of sand with resin and catalyst to make molds and cores, and the emissions released when molten iron is poured into the molds. 1.3 Description of the activities allowed by this permit action This permit action is Part 70 Reissuance. 1.4 Description of notifications and applications included in this action Table 2. Notifications and applications included in this action Date received Application/Notification type and description 12/30/2002 Part 70 Reissuance (IND ) Technical Support Document, Permit Number: Page 1 of 16

2 1.5 Facility emissions Table 3. Total facility potential to emit summary PM tpy PM10 tpy PM2.5 tpy SO2 tpy NOx tpy CO tpy CO2e tpy VOC tpy Single HAP tpy Total facility limited potential emissions Total facility actual emissions (2015) * 7.7 * *Not reported in Minnesota emission inventory. All HAPs tpy Table 4. Facility classification Classification Major Synthetic minor/area Minor/Area New Source Review X Part 70 X Part 63 X 1.6 Changes to permit The permit does not authorize any specific modifications, however, the MPCA has a combined operating and construction permitting program under Minnesota Rules Chapter 7007, and under Minn. R , the MPCA has authority to include additional requirements in a permit. Under that authority, the following changes to the permit are also made through this permit action: The permit has been updated to reflect current MPCA templates and standard citation formatting. Completed requirements and the requirements for equipment that has been removed have been deleted. Some requirements have been reordered to help with clarity (i.e., similar requirements are grouped). CAM has been added as discussed in Table 5 of this TSD. The former GP004 has been eliminated and requirements have been moved to individual control equipment. The former GP006 has been eliminated and requirements have been moved to individual stack vents. TREA 13 requirements were moved to a new group COMG 3. COMG 8 and the requirements of 40 CFR pt. 63, subp. ZZZZZ have been added. COMG 4 has been created and it includes all emissions units subject to Minn. R STRU 17, STRU 8, and STRU 15: Existing performance testing requirements have been updated to current template language, including expanded performance testing to determine compliance with the permit limits. TREA 14, TREA 16, TREA 18, and TREA 19 CAM requirements have been added to the permit. Annual metal melt limit of 60,000 tons for EQUI 7 Cupola so that the venturi scrubber (TREA 14) is classified as an other PSEU. Based on the PM 10 modeling completed in 2008, modeling parameters have been added as an appendix to the permit and requirements for when to re-model have been included at the Total Facility level in the permit according to MPCA policy. Technical Support Document, Permit Number: Page 2 of 16

3 2. Regulatory and/or statutory basis 2.1 New source review (NSR) Badger Foundry is one of 28 source categories listed in the Prevention Significant Deterioration (PSD) rules that are classified as major sources if the potential-to-emit (PTE) is equal or greater than 100 tons per year (tpy) of any single regulated pollutant. The facility is a major source under NSR. The Permittee has accepted limits on VOC emissions through previous permit actions such that the changes authorized were not considered a major modification under New Source Review (40 CFR 52.21) regulations. In addition, BACT limits were set on COMG 5 units in a previous permit action. No changes are authorized through this permit action. 2.2 Part 70 permit program The facility is a major source under the Part 70 permit program. 2.3 New source performance standards (NSPS) The Permittee has stated that no New Source Performance Standards apply to the operations at this facility. 2.4 National emission standards for hazardous air pollutants (NESHAP) The facility has accepted limits on HAP emissions such that it is an area source under 40 CFR pt. 63. Thus, no major source NESHAPs apply. The facility is an existing small foundry subject to the requirements of 40 CFR 63 Subpart ZZZZ, National Standards for Hazardous Air Pollutants for Iron and Steel Foundries Area Sources. Subpart ZZZZZ has been incorporated into the permit; the NESHAP general requirements (Subpart A) are incorporated via attachment of the rule as Appendix F, and listing of the applicable portions in Section 5 of the permit. 40 CFR (f) refers to the submittal of compliance reports according to 63.10(e), which refers to sources with CEMS. As Badger doesn t have CEMS on site, the MPCA consulted with EPA Region V, to confirm the requirement is accurate. Air Enforcement in Region 5 indicated that 63.10(e) was retained in case there may be CEMS data, and believes that the rule was intended to be read 63.10(d) and 63.10(e) as applicable, and doesn t know about the intentions for a rule change. Those changes are included in this permit. 2.5 Compliance assurance monitoring (CAM) The table below lists the sources subject to CAM, the control equipment used, whether the source is a large or other pollutant specific emission unit (PSEU), and the pollutants triggering CAM. Table 5. CAM summary Unit Control CAM applicability Pollutant EQUI 18, EQUI 2, EQUI 17 TREA 19 Fabric Filter Other PM/PM10 EQUI 24, EQUI 26, EQUI 27 TREA 16, Fabric Filter Other PM/PM10 EQUI 7 TREA 14, Venturi Scrubber Other PM/PM10 EQUI 10, EQUI 9, EQUI 29, EQUI 20, EQUI 21 TREA 18, Fabric Filter Other PM/PM10 For large pollutant specific emission units, records of the monitored parameter must be made at a minimum of four times per hour, or once every 15 minutes. For other PSEUs (not large), records must be made at a minimum of once per 24 hours. See Attachment 3 to this document for the CAM Plan submitted by the applicant. Note that the CAM plan submitted by the applicant includes TREA 15; it has been determined that TREA 15 is not subject to CAM. Technical Support Document, Permit Number: Page 3 of 16

4 2.9 Minnesota State Rules Portions of the facility are subject to the following Minnesota Standards of Performance: Minn. R Standards of Performance for Fossil-Fuel-Burning Direct Heating Equipment Minn. R Standards of Performance for Post-1969 Industrial Process Equipment Table 6. Regulatory overview of facility Subject item* Applicable regulations Rationale TFAC 1 - Air Quality Total Facility COMG 3-2% or greater moisture COMG 4 Direct Heating Equipment COMG 5 Core Dip Tanks BACT limit COMG 6 Units subject to IPER COMG 7 HAPs limits COMG 8 units subject to NESHAP Subpart ZZZZZ COMG 10 Nobake sand reclaim system COMG 11 Omega-Kloster line COMG 12 - Core making machines Minn. R. ch. 7017, Minn. Stat. 116 modification under 40 CFR 52 Minn. R Title I Condition: 40 CFR (BACT source under 40 CFR Minn. R source under 40 CFR 63 Ambient Air Quality Standards: The facility previously conducted PM10 dispersion modeling. The permit contains conditions to ensure that any future changes in emissions or stack parameters result in equal or better dispersion characteristics. Prevention of Significant Deterioration (PSD). Limits on moisture content of mold sand to keep the modification minor under PSD. Standards of Performance for Fossil-Fuel-Burning Direct Heating Equipment. Determination of applicable requirements from rule: The facility is located outside the MSP Air Quality Control Region Rated heat input of the equipment is 250 MMBtu/hr Prevention of Significant Deterioration (PSD). BACT limit on total amount of dipping solution to be used per 12-month period Prevention of Significant Deterioration (PSD). Limit on VOC content of dipping solution to keep the modification minor under PSD. Standards of Performance for Post-1969 Industrial Process Equipment. Determination of applicable requirements from rule: Units constructed after 1969; No other Minnesota standards of performance apply. National Standards for Hazardous Air Pollutants. Limits on single and total HAPs from metal melting, pouring, cooling, shakeout, sand handling, cleaning, and finishing equipment to avoid major source classification under NESHAPs. 40 CFR 63, Subpart ZZZZZ National Standards for Hazardous Air Pollutants for Iron and Steel Foundries Area Sources. The facility is an area source of HAPs and is classified as a small foundry because the facility s metal melt production for calendar year 2008 was less than 20,000 tons. modification under 40 CFR modification under 40 CFR 52 source under 40 CFR 63.2 PSD. Limits on VOC emissions to avoid a major modification under PSD. PSD. Limits on VOC emissions to avoid a major modification under PSD. Calculation of HAP emissions pursuant to the overall HAP limit under COMG 7. EQUI 7 - Cupola 40 CFR 64.3 CAM. Limit on overall production rate such that post-control emissions are limited to less than 100 tpy, avoiding classification as a Large PSEU. Technical Support Document, Permit Number: Page 4 of 16

5 Subject item* Applicable regulations Rationale EQUI 10 Electric Induction Melting Furnace EQUI 23 Pouring/Cooling EQUI 44 Chemical Set Core EQUI 45 Chemical Set Core STRU 8, STRU 17, STRU 15 - Stack/Vents TREA Venturi Scrubber modification under 40 CFR 52 source under 40 CFR 63.2 source under 40 CFR Minn. R source under 40 CFR Minn. R Minn. R Prevention of Significant Deterioration (PSD). Limit on throughput to keep the modification minor under PSD. Calculation of HAP emissions pursuant to the overall HAP limit under COMG 7. PSD. Limits on VOC emissions to avoid a major modification under PSD. Standards of Performance for Post-1969 Industrial Process Equipment. Determination of applicable requirements from rule: Units constructed after 1969; No other Minnesota standards of performance apply. PSD. Limits on VOC emissions to avoid a major modification under PSD. Standards of Performance for Post-1969 Industrial Process Equipment. Determination of applicable requirements from rule: Units constructed after 1969; No other Minnesota standards of performance apply. Performance Test General Requirements 40 CFR 64 Compliance Assurance Monitoring source under 40 CFR PSD. Limits on control of PM, PM10, and PM2.5 to keep the modification minor under PSD. TREA Thermal Oxidizer source under 40 CFR 52 PSD. Limit on control of VOC to keep the modification minor under PSD. TREA 16, TREA 18, TREA Fabric Filter - Low Temp, T<180 Degrees F source under 40 CFR 52 PSD. Limits on PM, PM10, PM2.5 control efficiencies from molding, material handling, and grinding equipment, to avoid major modification requirements of PSD. 40 CFR 64 Compliance Assurance Monitoring *Location of the requirement in the permit (e.g., EQUI 1, STRU 2, etc.). 3. Technical information 3.1 Calculations of potential to emit (PTE) Attachment 1 to this TSD contains a summary of the PTE of the Facility, and detailed spreadsheets and supporting information prepared by the MPCA and the Permittee. PM, PM 10 and PM 2.5: PM, PM 10, PM 2.5 potential emissions are based on published emission factors from AP-42 Section for Gray Iron Foundries, EPA s WebFire Database, 1998 MPCA Iron Foundry Calculations Guidance Draft The major emission points from Badger Foundry Company are cupola melt, induction furnaces, melt charge handling, pouring and cooling, shake out and knock out, and cleaning operations. However the metal melting operations release the major portion of the total particulates. The emission factors from AP-42 Table are rated as D and E, which means that emission factors are based on general studies that used emission test not available for review, so production rate, scrap composition, type of furnace, charging and Technical Support Document, Permit Number: Page 5 of 16

6 pouring operations that cause peak emission loads, production and operating procedures, etc were unknown. The Permittee has used PM 10 emission factors from WebFire and MPCA Iron Foundry Calculations where no emission factor was found in AP-42 Table PM, PM 10, PM 2.5 potential emissions from combustion units and combustion fuel sources are based on published emissions factors (AP-42), EPA s WebFire Database, maximum capacity of the units, and fuel used. The capture efficiency of some control equipment is not 100%, therefore the Permittee is required to certify the hoods and keep records of the air flow or other information used to determine that the hood remains as certified. VOCs and HAPs: The main contributors of VOCs/HAPs emissions are from gray iron foundry-pouring, cooling, mold core production, burning natural gas, coke, and propane from fuel combustion sources. Fuel Combustion Sources: VOC and HAPs emissions from the combustion sources were calculated using emission factors for natural gas, coke, and liquid propane combustion taken from AP-42, WebFire, and rated heat input of the equipment. Mold, core production, and pouring: AP-42 does not provide any HAP emission factors for foundry operations. Insufficient data was presented to develop emission factors from these sources because of many types of resins currently in use have diverse and toxic compositions. Therefore, the VOC and HAPs emissions were calculated using: mass balance, VOCs content based on safety data sheets, Form R Reporting of Binder Chemicals Used in Foundries Fourth Edition (Appendices C and D), maximum contents of materials documented in Appendix E, and MPCA Iron Foundry Calculation Guidance (5/6/1998). Criteria and hazardous air pollutants and Greenhouse gases (GHGs) Potential emissions of criteria pollutants and hazardous air pollutants from natural gas combustion and liquid propane equipment are based on AP-42 emissions factors, maximum capacity of the units and fuel used. Potential emissions of criteria pollutants and hazardous air pollutants from coke combustion equipment are based on AP-42/WebFire, maximum capacity of the unit, and heating value. Greenhouse gases (GHGs) were calculated using emission factors from 40 CFR pt. 98, subp. C, and Global Warming Potentials factors from 40 CFR pt. 98, subp. A. 3.2 Dispersion modeling At the time of issuance of the initial Title V permit, the facility triggered the requirement to complete air dispersion modeling to show modeled compliance with the PM 10 national ambient air quality standards (NAAQS). The modeling was completed and demonstrated compliance with the NAAQS. A table of the modeled parameters has been added to the permit as an appendix. The parameters listed in Appendix B of the permit describe the operation of the facility at maximum capacity. In other words, the flow rates and temperatures listed in Appendix B represent the minimum parameters at the maximum emission rates. The MPCA does not require any specific compliance demonstration with these parameters because they are worst-case conditions. The purpose of listing the parameters in the permit appendix is to provide a benchmark for determining if and when additional modeling is required. Further modeling requirements are based on a tiered approach; based on how close the modeled impacts are to the standard, additional modeling requirements are based on whether a proposed change would result in an emissions increase that would require a permit amendment, and if the proposed change would result in equivalent or better dispersion characteristics. The following table presents a summary of the 2008 PM 10 dispersion modeling results in comparison to the applicable standard. Technical Support Document, Permit Number: Page 6 of 16

7 Table 7. Dispersion Modeling Results Summary Pollutant Year Modeled Impact (µg/m 3 ) C NAAQS (µg/m 3 ) Percent of Standard PM10 24-Hour A % PM10 Annual B % A 24-Hour impacts are based on the highest-sixth-high concentration over 5 modeled years. B Annual impacts are based in the highest-first-high concentration of each modeled year. C All background sources and concentrations are included in the modeled results. Table 8: Summary of Modeled Yearly Annual Averages & Highest Sixth Highest (5-Years) 24- Hour Average For Badger Foundry Co. Averaging Period Year Receptor Location X Y PM10 Conc. (μg/m3) Annual Annual Annual Annual Annual Hour (5 Year) - High 6th High Monitoring In accordance with the Clean Air Act, it is the responsibility of the owner or operator of a facility to have sufficient knowledge of the facility to certify that the facility is in compliance with all applicable requirements. For CAM, the Permittee submitted a CAM proposal as required by 40 CFR It can be found in Attachment 3 to this TSD. Further discussion of decisions about CAM can be found in Table 10. In evaluating the monitoring included in the permit, the MPCA considered the following: the likelihood of the facility violating the applicable requirements; whether add-on controls are necessary to meet the emission limits; the variability of emissions over time; the type of monitoring, process, maintenance, or control equipment data already available for the emission unit; the technical and economic feasibility of possible periodic monitoring methods; and the kind of monitoring found on similar units elsewhere. Table 10 summarizes the monitoring requirements. Technical Support Document, Permit Number: Page 7 of 16

8 Table 10. Monitoring Subject Item* Requirement (basis) What is the monitoring? Why is this monitoring adequate? COMG 3 Mold Sand Moisture Content >= 2 percent by weight. [Avoid major modification under 40 CFR 52.21] Daily recordkeeping This minimum moisture content helps to control dust created by conveying sand to the emission units in COMG 3. Badger s automatic moisture additional system is set to maintain mixed sand moisture content 2%. COMG 4 Total Particulate Matter: variable with airflow Opacity <= 20 percent opacity with exceptions. [Minn. R ] None All units use natural gas or propane back up; therefore, the likelihood of violating either of the emission limits is very small. The Permittee can demonstrate that these units will continue to operate such that emissions are well below the emission limits by only burning natural gas or propane. Since this is a permit condition, the semi-annual deviations report will document any deviations from this condition. Core Dipping Mixture Material Usage <= 1066 tons per year 12- month rolling sum. Daily recordkeeping and monthly calculations COMG 5 [40 CFR 52.21(j)(BACT)] VOC content <= 5.0 percent by weight of core dipping mixture. Ongoing recordkeeping based on SDS or MSDS Daily recordkeeping of material usage in tons and ongoing records of VOC contents will be adequate to verify compliance with the BACT limit. [Avoid major modification under 40 CFR 52.21] COMG 6 Total Particulate Matter: variable with airflow Opacity <= 20 percent opacity with exceptions. Proper O&M of control equipment from these units exhaust through baghouses. The actual limits are variable with air flow and product flow, but a properly maintained baghouse can easily meet the conservative limits of Minn. R [Minn. R ] Technical Support Document, Permit Number: Page 8 of 16

9 Subject Item* Requirement (basis) COMG 7 HAPs - Total <= 22.5 tons per year 12-month rolling sum HAPs - Single <= 9.0 tons per year 12-month rolling sum [Title I Condition: Avoid major source under 40 CFR 63.2] COMG 8 Operational requirements from 40 CFR pt. 63, Subpart ZZZZZ COMG 10 COMG 11 VOC <= 39.0 tons per year 12- month rolling sum [Avoid major modification under 40 CFR 52.21] VOC <= 39.0 tons per year 12- month rolling sum [Avoid major modification under 40 CFR 52.21] EQUI 7 Melted Metal <= tons per year 12-month rolling sum [Avoid large PSEU] EQUI 10 Melted Metal <= 5000 tons per year 12-month rolling sum [Avoid major modifiction under 40 CFR 52.21] What is the monitoring? Daily records of run time and flow rate On-going records of HAP contents Monthly calculation of HAP emissions Monitoring required under 40 CFR pt. 63, Subpart ZZZZZ, (e.g, inspections of control devices, performance testing) Recordkeeping: Daily run time and flow rate records; On-going SDS records of coating contents; Monthly calculations of emissions. Recordkeeping: Daily run time and flow rate records; On-going SDS records of coating contents; Monthly calculations of emissions. Recordkeeping: Daily records of metal melted; monthly recordkeeping & calculations Recordkeeping: Daily records of metal melted; monthly recordkeeping & calculations Why is this monitoring adequate? Calculations for individual units are located at COMG 12, EQUI 7, EQUI 10, and EQUI 23, since all calculations are slightly different. The monitoring required by 40 CFR pt. 63, Subpart ZZZZZ is considered adequate. No additional monitoring requirements were imposed. Daily and monthly recordkeeping combined with formulas that were established for monthly calculation of the 12-month rolling sum is adequate to ensure compliance with the emission limits. Daily and monthly recordkeeping combined with formulas that were established for monthly calculation of the 12-month rolling sum is adequate to ensure compliance with the emission limits. By limiting the tons of melt in the cupola, the controlled emissions are limited to less than 100 tpy and the venturi scrubber is considered to be an other PSEU under CAM rules. By limiting the tons of melt in the induction furnace, emissions from the rest of the emission units downstream are limited. Therefore, the Ductile Line modification was limited to less than 15 tons per year of PM10 and 25 tons per year PM to avoid classification as major modification under 40 CFR Technical Support Document, Permit Number: Page 9 of 16

10 Subject Item* Requirement (basis) What is the monitoring? None Why is this monitoring adequate? Equipment is within a building and does not exhaust through a stack or vent. While testing of the unit is not feasible, it is assumed that since any dust generated is not collected or controlled, the quantity is well below that allowed by Minn. R EQUI 44 Total Particulate Matter: variable with airflow Opacity <= 20 percent opacity with exceptions. [Minn. R ] VOC <= 39.0 tons per year 12- month rolling sum [Avoid major source under 40 CFR 52.21] Recordkeeping: Daily records of run time and flow rate. On-going SDS records of coating contents; Monthly calculations of emissions. None Daily and monthly recordkeeping with formulas that were established for monthly calculation of the 12- month rolling sum ensure compliance with the emission limits. EQUI 45 Total Particulate Matter: variable with airflow Opacity <= 20 percent opacity with exceptions. [Minn. R ] VOC <= 39.0 tons per year 12- month rolling sum [Avoid major modification under 40 CFR 52.21] Equipment is within a building and does not exhaust through a stack or vent. While testing of the unit is not feasible, it is assumed that since any dust generated is not collected or controlled, the quantity is well below that allowed by Minn. R Recordkeeping: Daily records of run time and flow rate. Daily and monthly recordkeeping with formulas that were established for monthly calculation of the 12- month rolling sum ensure compliance with the emission limits. On-going SDS records of coating contents; Monthly calculations of emissions. Technical Support Document, Permit Number: Page 10 of 16

11 Subject Item* TREA 14 Venturi Scrubber subject to CAM TREA 15 Thermal Oxidizer Requirement (basis) Particulate Matter >= 94 percent control efficiency PM < 10 micron >= 84 percent control efficiency. [Avoid major modification under 40 CFR 52.21] PM < 2.5 micron >= 84 percent control efficiency [Minn. R ] Pressure Drop >= 52 inches of water [Title I Condition: Avoid major modification under 40 CFR 52.21] Water pressure >= 50 psi (gauge) [Avoid major modification under 40 CFR 52.21] Volatile Organic Compounds >= 97 percent control efficiency [Avoid major modification under 40 CFR 52.21] What is the monitoring? Proper operation and maintenance of control device in accordance with O & M Plan Recordkeeping of pressure drop and water pressure Operation in compliance with CAM plan Recordkeeping once every 24 hours Recordkeeping once every 24 hours Proper operation and maintenance of control device in accordance with O & M Plan Recordkeeping of temperature Why is this monitoring adequate? Monitoring according to a CAM plan that fulfills the requirements of 40 CFR 64 is sufficient to assure compliance with the control efficiency limits (and in turn demonstrate compliance with the particulate matter limits for EQUI 7). Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. CAM recordkeeping frequency for other PSEU. CAM recordkeeping frequency for other PSEU. The Permittee is required to record water supply pressure because the scrubber was modified since the first Title V application was filed, as the company that designed the modification recommended that the water supply pressure be monitored instead of water flow rate. Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. Technical Support Document, Permit Number: Page 11 of 16

12 Subject Item* Requirement (basis) What is the monitoring? Continuous monitoring of termperature Why is this monitoring adequate? Temperature >= 1200 degrees Fahrenheit 3- hour rolling average with a residence time of 0.30 seconds or greater [Avoid major modification under 40 CFR 52.21] TREA 16 Fabric Filter subject to CAM Particulate Matter >= 99 percent control efficiency. PM < 10 micron >= 93 percent control efficiency. [Avoid major source under 40 CFR 52.21] PM < 2.5 micron >= 93 percent control efficiency Proper operation and maintenance of control device in accordance with O & M Plan Monitoring of pressure drop Daily Recordkeeping of visible emissions Operation in compliance with CAM plan Monitoring according to a CAM plan that fulfills the requirements of 40 CFR 64 is sufficient to assure compliance with the control efficiency limits (and in turn demonstrate compliance with the particulate matter limits for EQUI 24, EQUI 26, and EQUI 27). Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. [Minn. R ] Pressure Drop >= 4 and <= 7 inches of water, [Avoid major modification under 40 CFR 52.21] Recordkeeping once every 24 hours CAM recordkeeping frequency for other PSEU. Technical Support Document, Permit Number: Page 12 of 16

13 Subject Item* Requirement (basis) What is the monitoring? Proper operation and maintenance of control device in accordance with O & M Plan Monitoring of pressure drop Daily Recordkeeping of visible emissions Why is this monitoring adequate? Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. TREA 17 Fabric Filter Particulate Matter >= 99 percent control efficiency. PM < 10 micron >= 93 percent control efficiency. [Avoid major source under 40 CFR 52.21] PM < 2.5 micron >= 93 percent control efficiency [Minn. R ] Pressure Drop >= 3 and <= 6 inches of water [Avoid major source under 40 CFR 52.21] Particulate Matter >= 99 percent control efficiency. PM < 10 micron >= 93 percent control efficiency. [Avoid major source under 40 CFR 52.21] PM < 2.5 micron >= 93 percent control efficiency [Minn. R ] Pressure Drop >= 3 and <= 7 inches of water [Avoid major source under 40 CFR 52.21] Recordkeeping once every 24 hours TREA 18 Fabric Filter subject to CAM Proper operation and maintenance of control device in accordance with O & M Plan Monitoring of pressure drop Daily Recordkeeping of visible emissions Operation in compliance with CAM plan Monitoring according to a CAM plan that fulfills the requirements of 40 CFR 64 is sufficient to assure compliance with the control efficiency limits (and in turn demonstrate compliance with the particulate matter limits for EQUI 10, EQUI 9, EQUI 29, EQUI 20, and EQUI 21). Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. Recordkeeping once every 24 hours CAM recordkeeping frequency for other PSEU. Technical Support Document, Permit Number: Page 13 of 16

14 Subject Item* TREA 19 Fabric Filter subject to CAM Requirement (basis) Particulate Matter >= 99 percent control efficiency. PM < 10 micron >= 93 percent control efficiency. [Avoid major source under 40 CFR 52.21] PM < 2.5 micron >= 93 percent control efficiency [Minn. R ] Pressure Drop >= 3 and <= 7 inches of water [Avoid major source under 40 CFR 52.21] What is the monitoring? Proper operation and maintenance of control device in accordance with O & M Plan Monitoring of pressure drop Daily Recordkeeping of visible emissions Operation in compliance with CAM plan Recordkeeping once every 24 hours *Location of the requirement in the permit (e.g., EQUI 1, ST 2, etc.). 3.4 Insignificant activities Why is this monitoring adequate? Monitoring according to a CAM plan that fulfills the requirements of 40 CFR 64 is sufficient to assure compliance with the control efficiency limits (and in turn demonstrate compliance with the particulate matter limits for EQUI 18, EQUI 2, and EQUI 17). Operation according to the O & M Plan along with periodic inspections ensure that potential issues with the control are discovered and corrective actions can be taken to prevent exceedances. As with other control efficiency limits the permit does not require verification of the control efficiency limits via inlet-outlet testing. Compliance with the control efficiency is assumed as long as the equipment is operated and maintained in accordance with permit requirements and the O & M Plan. CAM recordkeeping frequency for other PSEU. Badger Foundry Co has several operations which are classified as insignificant activities under the MPCA s permitting rules. These are listed in Appendix A to the permit. The permit is required to include periodic monitoring for all emissions units, including insignificant activities, per EPA guidance. The insignificant activities at this Facility are only subject to general applicable requirements. Using the criteria outlined earlier in this TSD, the following table documents the justification why no additional periodic monitoring is necessary for the current insignificant activities. See Attachment 1 of this TSD for PTE information for the insignificant activities. Table 11. Insignificant activities Insignificant activity Individual units with potential emissions less than 2000 lb/year of certain pollutants 42 natural gas heating units five sand silos two sand hoppers one fly ash silo. General applicable emission limit Minn. R Discussion The PTE of each unit is 1 tpy PM or less, well below the limits typically set through the Industrial Process Equipment Rule. In addition, these sources are either exhausted inside, or have no forced air exhaust system, which makes performance testing infeasible. 3.5 Permit organization In general, the permit meets the MPCA Tempo Guidance for ordering and grouping of requirements. One area where this permit deviates slightly from Tempo guidance is in the use of appendices. While appendices Technical Support Document, Permit Number: Page 14 of 16

15 are fully enforceable parts of the permit, in general, any requirement that the MPCA thinks should be electronically tracked (e.g., limits, submittals, etc.), should be in the Requirements table in Tempo. The main reason is that the appendices are word processing sections and are not part of the electronic tracking system. Violation of the appendices can be enforced, but the computer system will not automatically generate the necessary enforcement notices or documents. Staff must generate these. 3.6 Comments received This Section will be completed after the referenced review periods. Public Notice Period: [start date] [end date] EPA Review Period: [start date] [end date] 4. Permit fee assessment This permit action is the reissuance of an individual Part 70; therefore, no application fees apply under Minn. R , subp Conclusion Based on the information provided by Badger Foundry Company, the MPCA has reasonable assurance that the proposed operation of the emission facility, as described in the Air Permit No and this TSD, will not cause or contribute to a violation of applicable federal regulations and Minnesota Rules. Staff members on permit team: Orten Abad (permit engineer) Toni Volkmeier (permit engineer) Andrew Place (compliance reviewer) Kelsey Suddard (peer reviewer) Laurie O Brien (administrative support) TEMPO Activities: Part 70 Reissuance (IND ), Permit Reopening IND ) Attachments: 1. PTE summary and calculation spreadsheets 2. Subject item inventory and facility requirements 3. CAM Plans Technical Support Document, Permit Number: Page 15 of 16

16 Attachment 1 [PTE Summary and Increase Calculation Spreadsheets]

17 TotalPTEbypolutant AgencyInterest:None AgencyInterestID:423 Activity:None(Part70Reissuance) Detailsfor: SICategory:None SIType:None Polutant SubjectItem ID SubjectItem Designation SubjectItem Description Acetaldehy.EQUI23 EU003 Pouring/Cooling-OtherUnit Potential(lbs/hr) UnrestrictedPotential 3.26 PotentialLimited 2.33 Actual Total Acrolein EQUI23 EU003 Pouring/Cooling-OtherUnit Total Ammonia EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Arsenic EQUI7 EU001 Cupola-OtherUnit compounds EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion e e e e e e e-06 EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion 1.2e e e-06 EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 3.51e e e-06 EQUI41 EU071 CupolaStartUpTorch-OtherUnit 5.5e e e-07 TREA15 CE002 Afterburner-ThermalOxidizer 1.14e e e-06 Total e Benzene COMG7 GP011 HAP's-Limit 9 EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit 5.78e e e-06 EQUI23 EU003 Pouring/Cooling-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion 2.2e e e-05 EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion 1.27e e e-05 EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 3.69e e e-05 EQUI41 EU071 CupolaStartUpTorch-OtherUnit 5.78e e e-06 TREA15 CE002 Afterburner-ThermalOxidizer 1.2e e e-05 Total Berylium EQUI8 EU049 CupolaStartUpTorch-OtherUnit Compounds EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion e e e e e e e e e-07 EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 2.11e e e-08 EQUI41 EU071 CupolaStartUpTorch-OtherUnit 3.3e e e-08 TREA15 CE002 Afterburner-ThermalOxidizer 6.86e-08 3e-07 3e-07 Total Cadmium EQUI7 EU001 Cupola-OtherUnit compounds EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion 2.946e e e e e e e e e-05 EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion 6.63e e e-05 EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 1.93e e e-06 EQUI41 EU071 CupolaStartUpTorch-OtherUnit 3.03e e e-06 TREA15 CE002 Afterburner-ThermalOxidizer 6.29e e e-05 Carbon Dioxide Total EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit , , EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion 6, , EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion 3, , EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 1, , EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer 3, , Carbon Dioxide Equivalent Total EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion 40, , , , , , EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion 3, , EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion 1, , EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer 3, ,657.1 Carbon Monoxide Total EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit , , EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total EQUI7 EU001 Cupola-OtherUnit

18 TotalPTEbypolutant AgencyInterest:None AgencyInterestID:423 Activity:None(Part70Reissuance) Detailsfor: SICategory:None SIType:None Polutant Monoxide SubjectItem Total ID SubjectItem Designation SubjectItem Description Chromium EQUI7 EU001 Cupola-OtherUnit compounds EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Cobalt EQUI8 EU049 CupolaStartUpTorch-OtherUnit compounds EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Cumene(Iso EQUI3 EU054 ChemicalySetCore(350)-MixingEquipment propylbenze EQUI4 EU055 ChemicalySetCore(75)-MixingEquipment ne) EQUI22 EU064 No-BakeMoldMixer(450)-MixingEquipment EQUI44 EU007 ChemicalySetCore(150)-MixingEquipment EQUI45 EU008 ChemicalySetCore(250)-MixingEquipment Total Cyanide EQUI23 EU003 Pouring/Cooling-OtherUnit compounds Total Formaldehy.EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI23 EU003 Pouring/Cooling-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total HAPs-SingleCOMG7 GP011 HAP's-Limit Total HAPs-Total COMG7 GP011 HAP's-Limit EQUI3 EU054 ChemicalySetCore(350)-MixingEquipment EQUI4 EU055 ChemicalySetCore(75)-MixingEquipment EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI22 EU064 No-BakeMoldMixer(450)-MixingEquipment EQUI23 EU003 Pouring/Cooling-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit EQUI44 EU007 ChemicalySetCore(150)-MixingEquipment EQUI45 EU008 ChemicalySetCore(250)-MixingEquipment TREA15 CE002 Afterburner-ThermalOxidizer Total Hexane EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Lead EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI10 EU056 ElectricInductionMeltingFurnace-Furnace EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Manganese EQUI7 EU001 Cupola-OtherUnit compounds EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion Potential(lbs/hr) e e e e e-07 8e e e e e e e e e e e e e e e e e e e-06 UnrestrictedPotential e e e e e e e e e e e e e e e e e e e e e e e-05 1e-05 PotentialLimited e e e e e e e e e e e e e e e e e e e e e e e-05 1e-05 Actual

19 TotalPTEbypolutant AgencyInterest:None AgencyInterestID:423 Activity:None(Part70Reissuance) Detailsfor: SICategory:None SIType:None Polutant SubjectItem EQUI37 ID SubjectItem Designation EU067 SubjectItem MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion Description Manganese EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion compounds EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Mercury EQUI7 EU001 Cupola-OtherUnit Total Mercury EQUI8 EU049 CupolaStartUpTorch-OtherUnit Compounds EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Methane EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total Naphthalene COMG7 GP011 HAP's-Limit EQUI3 EU054 ChemicalySetCore(350)-MixingEquipment EQUI4 EU055 ChemicalySetCore(75)-MixingEquipment EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI22 EU064 No-BakeMoldMixer(450)-MixingEquipment EQUI23 EU003 Pouring/Cooling-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit EQUI44 EU007 ChemicalySetCore(150)-MixingEquipment EQUI45 EU008 ChemicalySetCore(250)-MixingEquipment TREA15 CE002 Afterburner-ThermalOxidizer Total Nickel EQUI8 EU049 CupolaStartUpTorch-OtherUnit compounds EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion Nitrogen Oxides Nitrous Oxide Particulate Matter EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI23 EU003 Pouring/Cooling-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI36 EU066 MakeUpAirUnit/CoreDept-OtherCombustion EQUI37 EU067 MakeUpAirUnit/GreenSandCleaningDept-OtherCombustion EQUI38 EU068 MakeUpAirUnit/4WheelBlasterBuilding-OtherCombustion EQUI41 EU071 CupolaStartUpTorch-OtherUnit TREA15 CE002 Afterburner-ThermalOxidizer Total COMG11 GP002 Omega-KlosterLine EQUI1 EU002 MeltChargeHandling-MaterialHandlingEquipment EQUI2 EU005 CastingShakeout/MoldDump-CastingEquipment EQUI3 EU054 ChemicalySetCore(350)-MixingEquipment EQUI4 EU055 ChemicalySetCore(75)-MixingEquipment EQUI7 EU001 Cupola-OtherUnit EQUI8 EU049 CupolaStartUpTorch-OtherUnit EQUI9 EU057 DuctileTreatmentOperations-CastingEquipment EQUI10 EU056 ElectricInductionMeltingFurnace-Furnace Potential(lbs/hr) 6.68e e e e e e e e e e e e e e e e e e e e e e e e UnrestrictedPotential 2.92e e e e e e-06 2e e e e e e e e e e e e e e e e e PotentialLimited 2.92e e e e e e-06 2e e e e e e e e e e e e e e e e e Actual