MEMORANDUM

DATE:	May 1, 2023

FROM:	Donna Lee Jones, U.S. Environmental Protection Agency; Gabrielle Raymond, RTI International

TO:	Electric Arc Furnace NSPS Technology Review Project File

SUBJECT:	Particulate Matter Emissions from Electric Arc Furnace Facilities  -  Final Rule
--------------------------------------------------------------------------------

INTRODUCTION

      This memorandum summarizes the data used to assess particulate matter (PM) emissions from electric arc furnace (EAF) steel manufacturing facilities as part of the technology review of new source performance standards (NSPS) for EAF constructed after October 21, 1974, and on or before August 17, 1983 (40 CFR, part 60, subpart AA); and the NSPS for EAF and argon oxygen decarburization (AOD) constructed after August 17, 1983 (40 CFR, part 60, subpart AAa). Under Clean Air Act (CAA), section 111(b)(1)(B), the technology review of the NSPS must occur at least every 8 years. The intended effect of the NSPS standards is to require all new, modified, and reconstructed EAF and AOD vessels at steel plants to control emissions to the level achievable through use of the best demonstrated system of continuous emission reduction (BSER), considering costs, nonair quality health and environmental impacts, and energy requirements. (See CAA section 111(a)(1)). Entities potentially regulated by this action include steel manufacturing facilities that operate EAF. There are approximately 100 EAF facilities currently in the United States of America (U.S.), with approximately nine new facilities estimated over the next 10 years.

DESCRIPTION OF EAF PROCESS

      An EAF is a metallurgical furnace used to produce carbon and alloy steels. The input material to an EAF is typically 100 percent scrap steel. Cylindrical, refractory-lined EAF are equipped with carbon electrodes that are raised or lowered through the furnace roof. With electrodes retracted, the furnace roof can be rotated to permit the charge of scrap steel by overhead crane. Electric current is passed between the electrodes and through the scrap, generating arcing and the generation of enough heat to melt the scrap steel charge. Alloying agents and fluxing materials usually are added through doors on the side of the furnace. After the melting and refining period (melting&refining), impurities (in the form of a slag) and the refined steel are poured from the furnace. If an AOD is present, it follows the EAF in the production sequence and is used to oxidize carbon, silicon, and impurities, such as sulfur, and reduce alloy additions compared to an EAF alone. Use of AODs reduces EAF heat times, improves quality control, and increases daily steel production. AODs are primarily used in stainless steel making.

      The production of steel in an EAF is a batch process. Cycles, or heats, range from about 1.5 to 5 hours to produce carbon steel and from 5 to 10 hours to produce alloy steel. Scrap steel is charged to begin a cycle, and alloying agents and slag forming materials are added for refining. Stages of each cycle normally are charging, melting, refining (which usually includes oxygen blowing), and tapping. All those operations generate particulate matter (PM) emissions.

      Air emission control techniques typically involve an air emission capture system and a gas cleaning system. Air emission capture systems used in the EAF industry include direct shell evacuation control (DEC) systems, side draft hoods, combination hoods, canopy hoods, scavenger ducts, and furnace enclosures. The DEC system consists of ductwork attached to a separate opening, or "fourth hole", at the top (roof) of the furnace, which draws emissions to a gas cleaner and which works only when the furnace is upright and the top (roof) is in place. Side draft hoods collect furnace off gases from around the electrode holes and work doors after the gases leave the furnace. A combination hood incorporates elements from the side draft and DEC systems. Canopy hoods and scavenger ducts are used to address charging and tapping emissions. Baghouses are typically used as gas cleaning systems, i.e., control devices. Emissions of pollutants from the furnace via side draft or DEC systems are called "primary" emissions, and emissions from charging and tapping are called "secondary" emissions.

 3.0	PM EMISSIONS FACTORS FOR EAF BAGHOUSES AND FACILITIES

 3.1	PM Test Data from 2010&2016 Information Test Request

      Test data were obtained in 2010 and 2016 from baghouses (also known as fabric filters) at EAF facilities by the U.S. Environmental Protection Agency (EPA) under CAA section 114 authority in an information collection request (CAA section 114 request). The 2010 CAA section 114 request included a request for new testing in 2010 for PM and opacity (and mercury), and any previous test reports for PM and opacity (and mercury) over the previous 5 years (2005 to 2009). The EPA Test Method 5 was followed for PM tests and EPA Test Method 9 for opacity. In 2010, a total of 165 reports were obtained from 31 EAF facilities. In 2016, EPA requested new testing under CAA section 114 authority. A total of 10 reports were obtained from three EAF facilities that had previously submitted test reports in 2010 and included test reports from new testing in 2016 and 2017. In addition, two PM and opacity test reports were obtained from EPA Region V for two EAF facilities. These reports and their data from 33 facilities comprise the EPA's EAF test data for PM and opacity that was used in the technology review of the EAF NSPS. Copies of the PM test reports can be found in the docket for this rule (EPA-OAR-HQ-2002-0049). Appendix A contains an Excel(TM) file with details of the compiled 2010 section 114 request PM test data for EAF.

      The EAFs and baghouses at the EAF facilities in the EAF test data were in various combinations of baghouses controlling primary or secondary emissions as listed below:

 One EAF with one combination primary and secondary baghouse;
 One EAF with multiple baghouses, in various combinations;
 Multiple EAFs with one combination primary and secondary baghouse;
 Multiple EAFs with one primary and one secondary baghouse for the facility;
 Multiple EAFs each with one individual baghouse; and
 Multiple EAFs each with multiple individual baghouses, in various combinations and types.

There were also cases where EAFs had baghouses with multiple stacks, which are common in positive pressure baghouses. In these cases, the stack emissions and air flow were combined into one value for the baghouse.

      At the EAF facilities whose test reports from obtained from the 2010 test request were analyzed, there were six potential configurations of baghouses, as follows: (1) one EAF with one combined primary and secondary baghouse; (2) multiple EAF with one combination primary and secondary baghouse; (3) one EAF with multiple baghouses; (4) multiple EAFs with one primary and one secondary baghouse, total; (5) multiple EAFs each with one individual baghouse; and (6) multiple EAFs with multiple individual baghouses. Also, in some of the six configurations, the baghouses had multiple stacks so that the emissions from all stacks were combined to produce one emission factor for the baghouse. The situation with multiple stacks could occur at any of the six configurations listed above. Appendix B contains an Excel(TM) file showing the calculations used to develop emission factors from the compiled 2010 PM section 114 request test data, as described in this section. The test data were analyzed by individual baghouse to calculate the average PM emitted per unit air flow and compared to the NSPS control device standard that is applicable to each individual baghouse, at 12 milligrams per dry standard cubic meter (mg/dscm) [0.0052 grains per dry standard cubic feet (gr/dscf)] for EAF complying with the 1975 and 1984 NSPS for EAF (40 CFR part 60, subparts AA and AAa). Table 1 lists the facilities, their baghouse, and average baghouse emission data in units of gr/dscf (as a straight average of all runs from the baghouses; not flow weighted). Figure 1 shows the ranked data from the 54 baghouses listed in Table 1, expressed as a percent of the standard. The NSPS standard also is shown in Figure 1, as a straight line. Average baghouse PM emissions data ranged from a low of 0.83 percent of the NSPS standard to 44 percent of the NSPS standard (equivalent to a low value of 4.3E05 gr/dscf (0.10 mg/dscm) to a high value of 2.3E-03 gr/dscf (5.3 mg/dscm). The line of best fit for the data, as an exponential curve, is also shown in
Figure 1.

      The EAF test data also were used to develop emission factors in the format of total PM emitted per unit of flow for all baghouses combined at each facility. Because the number of baghouses is not addressed in the NSPS for EAF, facilities currently have the choice of splitting their emissions into more than one baghouse or combining into one control device. Table 2 lists the EAF facilities from the EPA test data and the total PM emissions from baghouses in gr/dscf that were calculated from run-by-run data, in gr/min for PM emissions and dscf/min for flowrate. The run-by-run PM data in gr/min were averaged for each test which then were divided by similar run-by-run averages for baghouse flowrates in dscf/min to obtain PM emissions in gr/dscf for each baghouse. Total facility baghouse emissions in gr/dscf were obtained from the sum of the gr/dscf emissions for each baghouse (in essence, emissions were flow weighted). Figure 2 shows the data from Table 2 ranked low to high.

      The EAF test data also were analyzed in terms of average mass of PM per mass of steel produced, i.e., pounds (lb) PM per ton of steel (or milligram (mg) PM per megagram (Mg) of steel). The lb/ton ratios were develop for each run using the tons/hr steel production rate for the run and the lb/hr PM emission rates for the same run. Total facility PM emissions in lb/ton were obtained by summing the PM lb/ton emissions rates for each baghouse, similar to the procedure described above for gr/dscf emissions. Not all facilities and test data were able to be used to create emissions factors in mass units. In some cases, no production data were available for some or all the runs. One reason for fewer or no run data was because the production rate was reported as confidential business information; another reason was because the facility reported production in weight of steel per heat and not per hour. However, at least three runs of data were available, minimally, for each baghouse in the data that were used. Table 3 lists the 30 facilities with data available to be expressed in units of lb/ton and the baghouse emission data for their 50 baghouse. Figure 3 shows the ranked baghouse mass data in lb/ton for the data in Table 3. Average baghouse PM emissions values ranged from 1.1E-03 to 1.2E-01 lb PM/ton steel produced (5.3E-04 to 5.9E-02 g PM/kg steel produced). The line of best fit for the data, an exponential curve, is also shown in Figure 3.

      The baghouse mass-based test data in mass of PM per mass of steel produced were used to develop a total facility mass-based emission factor for all baghouses combined at each facility. Table 4 lists the 30 facilities and their mass-based total facility baghouse PM emissions in lb/ton. Figure 4 shows the total facility PM emissions in lb/ton for the 30 facilities in Table 4. Facility total PM emission values ranged from 4.9E-03 to 1.61E-01 lb PM/ton steel produced (2.4E-03 to 8.1E-02 g PM/kg steel produced). The line of best fit for the data, an exponential curve, is also shown in Figure 4.
Table 1. EAF Baghouse Information and Average PM Emission Concentration (gr/dscf)[1]
                                     Count
                          Facility Name and Location
                              Baghouse(s) Tested
                                 Baghouse Type
                      Baghouse Average Flow Rate (dscfm)
                    Baghouse Average PM Emissions (gr/dscf)
                               Baghouse Average
                         PM as % EAF NSPS Standard[2]
                                       1
AK Steel-Butler-PA
BH #1/#2
AOD
                                    530,762
                                    1.7E-04
                                     3.2%
                                       2
AK Steel-Butler-PA
BH #3
EAF P/S
                                   1,129,208
                                    3.7E-04
                                     7.1%
                                       3
AK Steel-Mansfield-OH
BH #8
EAF P/S
                                    320,951
                                    4.0E-04
                                     7.7%
                                       4
AK Steel-Mansfield-OH
BH #9
EAF P/S
                                    480,222
                                    1.6E-03
                                      31%
                                       5
Allegheny-Brackenridge-PA
EAF 2 Canopy BH
EAF S
                                    340,590
                                    2.5E-04
                                     4.7%
                                       6
Allegheny-Brackenridge-PA
EAF2DECBH 2A,B
EAF P
                                    56,261
                                    2.6E-04
                                     4.9%
                                       7
Allegheny-Brackenridge-PA
EAF1,DECBH1A,B
EAF P
                                    37,294
                                    4.3E-04
                                     8.3%
                                       8
Allegheny-Brackenridge-PA
EAF1, AOD BH
EAF S/AOD
                                    524,160
                                    1.2E-03
                                      24%
                                       9
Allegheny-Latrobe-PA
EAF BH Stack
EAF P/S
                                    73,051
                                    5.4E-04
                                      10%
                                      10
Allegheny-Latrobe-PA
AOD BH Stack
AOD
                                    49,506
                                    1.1E-03
                                      21%
                                      11
CMC-Birmingham-AL
BH #2
EAF P/S
                                    10,024
                                    1.3E-03
                                      25%
                                      12
CMC-Birmingham-AL
BH #1
EAF P/S
                                    25,686
                                    2.1E-03
                                      39%
                                      13
CMC-Cayce-SC
EAF BH
EAF P/S
                                    531,227
                                    1.5E-03
                                      29%
                                      14
CMC-Mesa-AZ
EAF Meltshop BH1
EAF P/S
                                    272,545
                                    2.3E-04
                                     4.5%
                                      15
CMC-Seguin-TX
Reverse Air BH
EAF P
                                    613,328
                                    3.6E-04
                                     6.9%
                                      16
CMC-Seguin-TX
Pulse Jet BH
EAF S
                                    392,579
                                    4.0E-04
                                     7.7%
                                      17
Gerdau-Beaumont-TX
EAF BH EPN-2A
EAF P/S
                                    805,501
                                    4.7E-04
                                     9.0%
                                      18
Gerdau-Cartersville-GA
EAF BH 3
EAF S
                                    347,890
                                    4.5E-04
                                     8.7%
                                      19
Gerdau-Cartersville-GA
EAF BH 4
EAF S
                                    377,116
                                    8.8E-04
                                      17%
                                      20
Gerdau-Cartersville-GA
EAF BH (1/2)
EAF P
                                    634,076
                                    1.7E-03
                                      33%
                                      21
Gerdau-Charlotte-NC
EAF Melt Shop BH
EAF P/S
                                    401,580
                                    4.8E-04
                                     9.3%
                                      22
Gerdau-Jackson-MI
BH #3
EAF P/S
                                    640,185
                                    5.3E-04
                                      10%
                                      23
Gerdau-Jackson-TN
BH #2
EAF P
                                    551,591
                                    1.0E-03
                                      20%
                                      24
Gerdau-Jackson-TN
BH #1
EAF S
                                    347,406
                                    1.7E-03
                                      32%
                                      25
Gerdau-Jacksonville-FL
EAF BH #5
EAF P/S
                                    812,791
                                    5.5E-04
                                      11%
                                      26
Gerdau-Knoxville-TN
BH #4
EAF P
                                    268,143
                                    3.8E-04
                                     7.3%
                                      27
Gerdau-Knoxville-TN
BH #2
EAF S
                                    157,973
                                    2.3E-03
                                      44%
                                      28
Gerdau-St.Paul-MN
New BH
EAF P/S
                                    498,770
                                    1.4E-03
                                      27%
                                      29
Gerdau-Wilton-IA
EAF BH
EAF P/S
                                    492,154
                                    4.4E-04
                                     8.4%
                                      30
N. American Stainless-Ghent-KY
EAF-2
EAF P/S
                                    621,296
                                    8.2E-04
                                      16%
                                      31
N. American Stainless-Ghent-KY
AOD-2
AOD
                                    907,920
                                    9.8E-04
                                      19%
                                      32
N. American Stainless-Ghent-KY
AOD-1
AOD
                                    509,736
                                    1.0E-03
                                      20%
                                      33
N. American Stainless-Ghent-KY
EAF-1
EAF P/S
                                    493,505
                                    1.2E-03
                                      23%
                                      34
Nucor-Blytheville-AR
EAF SN-01
EAF P/S
                                   1,861,498
                                    5.7E-04
                                      11%
                                      35
Nucor-Cofield-NC
Melt Shop BH
EAF P/S
                                   1,149,386
                                    1.2E-04
                                     2.3%
                                      36
Nucor-Crawfordsville-IN
Melt Shop BH #1
EAF P/S
                                   1,177,717
                                    3.4E-04
                                     6.6%
                                      37
Nucor-Crawfordsville-IN
Melt Shop BH #2
EAF P/S
                                    870,074
                                    6.8E-04
                                      13%
                                      38
Nucor-Darlington-SC
EAF BH #2
EAF S
                                    391,790
                                    4.3E-05
                                     0.83%
                                      39
Nucor-Darlington-SC
EAF BH #1
EAF P
                                    327,025
                                    1.8E-04
                                     3.4%
                                      40
Nucor-Huger-SC
Canopy BH
EAF S
                                    435,267
                                    7.8E-04
                                      15%
                                      41
Nucor-Huger-SC
Melt Shop BH
EAF P
                                   1,097,380
                                    1.6E-03
                                      31%
                                      42
Nucor-Jewett-TX
Melt Shop BH
EAF P/S
                                   1,274,653
                                    1.7E-03
                                      32%
                                      43
Nucor-Norfolk-NE
EAF BH
EAF P/S
                                    558,700
                                    1.7E-04
                                     3.2%
                                      44
Nucor-Plymouth-UT
EAF BH
EAF P/S
                                    649,537
                                    4.9E-04
                                     9.4%
                                      45
Steel Dynamics-Butler-IN
EAF 2 BH
EAF P/S
                                    928,507
                                    2.3E-04
                                     4.5%
                                      46
Steel Dynamics-Butler-IN
EAF 1 BH
EAF P/S
                                   1,231,307
                                    2.6E-04
                                     5.0%
                                                                    (continued)

                                      47
Steel Dynamics-Columbia City-IN
EAF BH
EAF P/S
                                   1,103,398
                                    1.0E-04
                                     1.9%
                                      48
Steel Dynamics-Pittsboro-IN
EAF/LMF BH
EAF P/S
                                    475,850
                                    3.5E-04
                                     6.7%
                                      49
SSAB-Axis-AL
EAF BH
EAF P/S
                                    877,453
                                    6.3E-04
                                      12%
                                      50
Sterling Steel-Sterling-IL
EAF #8 South BH
EAF P/S
                                    863,622
                                    1.9E-03
                                      37%
                                      51
Sterling Steel-Sterling-IL
EAF #8 North BH
EAF P/S
                                    863,622
                                    2.1E-03
                                      41%
                                      52
Timken-Faircrest-OH
EAF Press BH
EAF P/S
                                   1,130,774
                                    1.8E-04
                                     3.5%
                                      53
Timken-Harrison-OH
# 9 EAF PP BH 5
EAF P/S
                                    969,257
                                    1.2E-04
                                     2.3%
                                      54
Timken-Harrison-OH
# 2 EAF PP BH 4
EAF P/S
                                    732,841
                                    1.3E-04
                                     2.5%
[1] AOD = argon-oxygen decarburization. BH = BH. dscfm = dry standard cubic feet per minute. EAF = electric arc furnace. gr/dscf = grains per dry standard cubic feet. LMF = ladle metallurgy facility. P = primary emissions. PM = particulate matter (filterable). PP = positive pressure. P/S = BH controlling both primary and secondary emissions. S = secondary emissions.
[2] The EAF NSPS standard for facilities built, modified or reconstructed prior to 2022 is 0.0052 gr/dscf.

Figure 1. EAF baghouse data as percent of current NSPS standard (12 mg/dscm or 0.0052 gr/dscf).

Table 2. Total Facility Baghouse PM Emissions from 2010 CAA section 114 Request (gr/dscf)
                                   Facility
                                (alphabetical)
                     Total Facility Baghouse PM Emissions
                                   (gr/dscf)
AK Steel-Butler-PA
                                   3.03E-04
AK Steel-Mansfield-OH
                                   3.40E-03
Allegheny-Brackenridge-PA
                                   2.05E-03
CMC-Birmingham-AL
                                   3.33E-03
CMC-Cayce-SC
                                   9.01E-03
CMC-Mesa-AZ
                                   2.33E-04
CMC-Seguin-TX
                                   9.54E-04
Gerdau-Beaumont-TX
                                   9.06E-04
Gerdau-Cartersville-GA
                                   1.46E-03
Gerdau-Charlotte-NC
                                   9.32E-04
Gerdau-Jackson-MI
                                   5.33E-04
Gerdau-Jackson-TN
                                   1.28E-03
Gerdau-Jacksonville-FL
                                   2.81E-03
Gerdau-Knoxville-TN
                                   2.42E-03
Gerdau-St.Paul-MN
                                   8.29E-03
Gerdau-Wilton-IA
                                   8.30E-04
North American Stainless-Ghent-KY
                                   1.62E-03
Nucor-Blytheville-AR
                                   3.72E-03
Nucor-Cofield-NC
                                   6.10E-04
Nucor-Crawfordsville-IN
                                   1.81E-03
Nucor-Darlington-SC
                                   2.94E-04
Nucor-Huger-SC
                                   6.88E-03
Nucor-Jewett-TX
                                   6.63E-03
Nucor-Norfolk-NE
                                   9.86E-04
Nucor-Plymouth-UT
                                   2.95E-03
SSAB-Axis-AL
                                   4.32E-03
Steel Dynamics-Butler-IN
                                   3.51E-04
Steel Dynamics-Columbia City-IN
                                   1.00E-04
Sterling Steel-Sterling-IL
                                   6.05E-03
Timken-Faircrest-OH
                                   1.82E-04
Timken-Harrison-OH
                                   1.25E-04

Figure 2. Total facility baghouse PM Emissions (gr/dscf) from 2010 CAA section 114 request.

Table 3. EAF Baghouse Information and Average Baghouse PM Emission Rate (lb/ton)
                      from 2010 CAA Section 114 Request.
                                     Rank
                            Facility Name, Location
                              Baghouse(s) Tested
                                 Baghouse Type
                    Baghouse Average PM Emissions (lb/ton)
                                       1
Nucor-Darlington-SC
EAF BH #2
EAF S
                                    1.1E-03
                                       2
Allegheny-Brackenridge-PA
EAF1, DEC BH 1A, 1B
EAF P
                                    2.1E-03
                                       3
Steel Dynamics-Butler-IN
EAF 2 BH
EAF P/S
                                    2.3E-03
                                       4
Allegheny-Brackenridge-PA
EAF 2, DEC BH 2A, 2B
EAF P
                                    2.5E-03
                                       5
Nucor-Darlington-SC
EAF BH #1
EAF P
                                    4.0E-03
                                       6
AK Steel-Butler-PA
BH #1/#2
AOD
                                    4.8E-03
                                       7
Steel Dynamics-Butler-IN
EAF 1 BH
EAF P/S
                                    4.8E-03
                                       8
Nucor-Cofield-NC
Melt Shop BH
EAF P/S
                                    4.9E-03
                                       9
Steel Dynamics-Columbia City-IN
EAF BH
EAF P/S
                                    5.8E-03
                                      10
Nucor-Norfolk-NE
EAF BH
EAF P/S
                                    6.0E-03
                                      11
Nucor-Crawfordsville-IN
Melt Shop BH #2
EAF P/S
                                    6.5E-03
                                      12
Nucor-Huger-SC
Canopy BH
EAF S
                                    8.6E-03
                                      13
Nucor-Crawfordsville-IN
Melt Shop BH #1
EAF P/S
                                    9.1E-03
                                                                    (continued)

                                      14
Gerdau-Cartersville-GA
EAF BH 3
EAF S
                                    9.6E-03
                                      15
CMC-Seguin-TX
Pulse Jet BH
EAF S
                                    9.9E-03
                                      16
Gerdau-Knoxville-TN
BH #4
EAF P
                                    1.2E-02
                                      17
CMC-Seguin-TX
Reverse Air BH
EAF P
                                    1.2E-02
                                      18
Timken-Faircrest-OH
EAF Pressurized BH
EAF P/S
                                    1.3E-02
                                      19
CMC-Mesa-AZ
1 EAF Melt Shop BH
EAF P/S
                                    1.3E-02
                                      20
CMC-Birmingham-AL
BH #2
EAF P/S
                                    1.6E-02
                                      21
Timken-Harrison-OH
# 2 EAF Positive Pressure BH 4
EAF P/S
                                    1.7E-02
                                      22
Allegheny-Brackenridge-PA
EAF 2 Canopy BH
EAF S
                                    1.8E-02
                                      23
Nucor-Plymouth-UT
EAF BH
EAF P/S
                                    1.9E-02
                                      24
Nucor-Blytheville-AR
EAF SN-01
EAF P/S
                                    1.9E-02
                                      25
Timken-Harrison-OH
# 9 EAF Positive Pressure BH 5
EAF P/S
                                    2.0E-02
                                      26
Gerdau-Cartersville-GA
EAF BH 4
EAF S
                                    2.1E-02
                                      27
Gerdau-Wilton-IA
EAF BH
EAF P/S
                                    2.2E-02
                                      28
Gerdau-Charlotte-NC
EAF Melt Shop BH
EAF P/S
                                    2.3E-02
                                      29
Allegheny-Brackenridge-PA
EAF1, AOD BH
EAF S/AOD
                                    2.4E-02
                                      30
AK Steel-Butler-PA
BH #3
EAF P/S
                                    2.6E-02
                                      31
AK Steel-Mansfield-OH
BH #8
EAF P/S
                                    3.0E-02
                                      32
North American Stainless-Ghent-KY
AOD-1
AOD
                                    3.2E-02
                                      33
North American Stainless-Ghent-KY
EAF-2
EAF P/S
                                    3.2E-02
                                      34
Gerdau-Jacksonville-FL
EAF BH #5
EAF P/S
                                    3.7E-02
                                      35
North American Stainless-Ghent-KY
FFBF EAF-1
EAF P/S
                                    3.9E-02
                                      36
CMC-Birmingham-AL
BH #1
EAF P/S
                                    3.9E-02
                                      37
Gerdau-Beaumont-TX
EAF BH
EAF P/S
                                    4.1E-02
                                      38
Gerdau-Knoxville-TN
BH #2
EAF S
                                    4.3E-02
                                      39
Nucor-Huger-SC
Melt shop BH
EAF P
                                    4.4E-02
                                      40
Gerdau-Jackson-TN
BH #2
EAF P
                                    4.9E-02
                                      41
Gerdau-Jackson-TN
BH #1
EAF S
                                    5.1E-02
                                      42
Gerdau-Jackson-MI
BH #3
EAF P/S
                                    5.4E-02
                                      43
North American Stainless-Ghent-KY
AOD-2
AOD
                                    5.4E-02
                                      44
CMC-Cayce-SC
EAF BH
EAF P/S
                                    6.4E-02
                                      45
Gerdau-St.Paul-MN
New BH
EAF P/S
                                    7.0E-02
                                      46
Sterling Steel-Sterling-IL
EAF #8 South BH
EAF P/S
                                    7.6E-02
                                      47
Sterling Steel-Sterling-IL
EAF #8 North BH
EAF P/S
                                    8.5E-02
                                      48
Gerdau-Cartersville-GA
EAF BH 1/2
EAF P
                                    8.5E-02
                                      49
AK Steel-Mansfield-OH
BH #9
EAF P/S
                                    1.1E-01
                                      50
Nucor-Jewett-TX
Melt shop BH stack
EAF P/S
                                    1.2E-01
Note: AOD = argon-oxygen decarburization. BH = Baghouse. dscfm = dry standard cubic feet per minute. EAF = electric arc furnace. gr/dscf = grains per dry standard cubic feet. LMF = ladle metallurgy facility. P = primary emissions. PM = particulate matter (filterable). PP = positive pressure. P/S = Baghouse controlling both primary and secondary emissions. S = secondary emissions.

Figure 3. EAF baghouse PM emission rate data (lb PM/ton steel) from 2010 CAA section 114 request.

              Table 4. Facility Total Baghouse PM Emission Rate
              (lb PM/ton steel) from 2010 CAA Section 114 Request
                                     Rank
                            Facility Name/Location
                 Facility Total Baghouse PM Emissions (lb/ton)
                                       1
Nucor-Cofield-NC
                                    4.9E-03
                                       2
Nucor-Darlington-SC
                                    5.1E-03
                                       3
Steel Dynamics-Columbia City-IN
                                    5.8E-03
                                       4
Nucor-Norfolk-NE
                                    6.0E-03
                                       5
Steel Dynamics-Butler-IN
                                    7.1E-03
                                       6
Timken-Faircrest-OH
                                    1.3E-02
                                       7
CMC-Mesa-AZ
                                    1.3E-02
                                       8
Nucor-Crawfordsville-IN
                                    1.6E-02
                                       9
Nucor-Plymouth-UT
                                    1.9E-02
                                      10
Nucor-Blytheville-AR
                                    1.9E-02
                                      11
Gerdau-Wilton-IA
                                    2.2E-02
                                      12
CMC-Seguin-TX
                                    2.2E-02
                                      13
Gerdau-Charlotte-NC
                                    2.3E-02
                                      14
AK Steel-Butler-PA
                                    3.1E-02
                                      15
Timken-Harrison-OH
                                    3.6E-02
                                      16
Gerdau-Jacksonville-FL
                                    3.7E-02
                                      17
Gerdau-Beaumont-TX
                                    4.1E-02
                                      18
Allegheny-Brackenridge-PA
                                    4.7E-02
                                                                    (continued)

                                      19
Nucor-Huger-SC
                                    5.2E-02
                                      20
Gerdau-Jackson-MI
                                    5.4E-02
                                      21
Gerdau-Knoxville-TN
                                    5.5E-02
                                      22
CMC-Birmingham-AL
                                    5.5E-02
                                      23
CMC-Cayce-SC
                                    6.4E-02
                                      24
Gerdau-St.Paul-MN
                                    7.0E-02
                                      25
Gerdau-Jackson-TN
                                    1.0E-01
                                      26
Gerdau-Cartersville-GA
                                    1.2E-01
                                      27
Nucor-Jewett-TX
                                    1.2E-01
                                      28
AK Steel-Mansfield-OH
                                    1.4E-01
                                      29
North American Stainless-Ghent-KY
                                    1.6E-01
                                      30
Sterling Steel-Sterling-IL
                                    1.6E-01
Note: lb/ton = pound per ton. PM = particulate matter.

Figure 4. EAF total facility baghouse PM emissions per mass of steel produced (lb/ton) from 2010 CAA section 114 request, and line of best fit.

 3.2	PM Data from 2005 CAA Section 114 Request for the 2007 EAF Area Source NESHAP

      In addition to the EAF test data from the 2010 CAA section 114 request, the EPA analyzed data obtained via the 2005 CAA section 114 request that was used to support the EAF area source National Emission Standards for Hazardous Air Pollutants (NESHAP) in 40 CFR part 63, subpart YYYYY, which was promulgated on 12/28/2007. (Docket Number EPA-HQ-OAR-2004-0083). The primary purpose of obtaining the 2005 CAA section 114 request data was to obtain another source of facility emission rate data in lb/ton and, more importantly, to verify whether the baghouse air-to-cloth (A/C) ratios that were in effect when the 2005 CAA section 114 request emissions data were determined were similar to the A/C ratio data taken from blast furnace baghouses at integrated iron and steel facilities that were as used in the EAF NSPS proposal. See "Cost Analyses to Determine BSER for PM Emissions and Opacity from EAF Facilities," (hereafter referred to as the "Cost Memorandum") for more details about the purpose of A/C ratios.

      The facility-wide lb/ton emissions derived from the 2005 CAA section 114 request data are shown in Table 5. Not all of the data submitted in the 2005 CAA section 114 request were able to be converted to the total facility emission rate in lb/ton because steel produced was not recorded for one or more baghouse tests. Figure 5 shows the data for the 12 EAF facilities where 2005 CAA section 114data were available to calculate a facility-wide lb/ton emissions. Comparison of the data from the 2010 CAA section 114 data (in Figure 4) to 2010 CAA section 114 data (Figure 5) is shown in Figure 6. The comparison shows agreement of the two data sets up to 0.08 lb/ton, with higher lb/ton values in the 2010 CAA section 114 data up to 0.16 lb/ton, the highest value. Appendix C shows the 2005 CAA section 114 request data for the 12 facilities. Test reports from the 2005 CAA section 114 request can be found in the docket to this rule.

 4.0	EAF OPACITY DATA

      Opacity test data also were collected in the 2010 CAA section 114 request described above. As part of the technology review, the EPA examined the opacity data for current facilities in the EAF test data that ranged over the years 2005 through 2011. For facilities with EAF that are subject to the 1975 and 1984 NSP, melt shop opacity must be less than 6 percent as measured by EPA Method 9 or a continuous emissions monitor (COMS). Under 40 CFR part 60, subpart AA (only), melt shop opacity during charging periods and tapping periods have limits of 20 percent and 40 percent opacity, respectively. In the EAF NSPS 40 CFR part 60, subparts AA and AAa, the exhaust from control devices must be less than 3 percent opacity and opacity from dust handling must be less than a 10 percent. The opacity data from the 33 facilities in the EPA's dataset revealed that all facilities operated at the limit for opacity from control device exhaust and for dust handling, at 3 percent and 10 percent, respectively. However, there were lower levels of opacity achieved from the melt shops for many of the 201/2016 CAA section 114 request facilities. The melt shop opacity data are discussed below. Copies of the opacity test reports can be found in the docket for this rule (EPA-OAR-HQ-2002-0049).

     Table 5. EAF Total Baghouse PM Emission Data (lb/ton) and A/C Ratios
                       from 2005 CAA Section 114 Request
                                   Facility
                                     City
                                     State
                                Baghouse Type
                               Flowrate (acfm)
                                Stack Test Date
                     Facility Total Baghouse PM (lb/ton)
                    Average A/C Ratio per Facility (ft/min)
Nucor Steel Nebraska
Norfolk
NE
EAF P/S
                                    965,000
                                  09/8-10/03
                                     0.009
                                      2.8
Nucor Plate Mill
Cofield
NC
EAF P/S
                                   1,200,000
                                  04/09-10/02
                                     0.013
                                      3.0
Nucor Steel Arkansas
Blytheville
AR
EAF P/S
                                   2,500,000
                                   8/29/2001
                                     0.014
                                      3.0
Nucor Bar Mill Group
Plymouth
UT
EAF P/S
                                    950,000
                                  02/25-26/03
                                     0.018
                                      2.1
North Star Steel
St. Paul
MN
EAF P/S
                                    600,000
                                    9/29/03
                                     0.019
                                      2.0
Nucor Steel - Berkeley
Huger
SC
EAF P/S
                                   1,450,000
                                   5/5/1999
                                     0.021
                                      2.6
IPSCO Steel
Axis
AL
EAF P/S
                                   1,600,000
                                   10/2-3/01
                                     0.032
                                      2.6
Gerdau AmeriSteel
Knoxville
TN
EAF S
                                    158,000
                                   12/11/00
                                     0.052
                                      3.5
SMI Steel
Cayce
SC
EAF P/S
                                    700,000
                                    2/22/01
                                     0.057
                                      3.3
Macsteel Arkansas
Fort Smith
AR
EAF S
                                    500,000
                                  04/26-27/01
                                     0.065
                                      2.9
Structural/SMI-Texas
Seguin
TX
EAF P&S
                                    550,000
                                   2/16/2000
                                     0.085
                                      6.0
IPSCO Steel Inc.
Muscatine
IA
EAF P/S
                                    980,000
                                  10/14-16/02
                                     0.087
                                      5.1

Figure 5. EAF total facility baghouse PM emissions per mass of steel produced (lb/ton) from 2005 CAA section 114 request, and line of best fit.

Figure 6. Comparison of 2005 and 2010 CAA section 114 request data for EAF total facility baghouse PM emissions per mass of steel produced (lb/ton).

      As part of the technology review for the EAF NSPS, the RACT/BACT/LAER Clearinghouse (RBLC) data repository was searched for decisions on Best Available Control Technology (BACT) for EAF, which is similar to the BSER used as criteria under CAA section 111 for NSPS. A match for EAF processes was found in the RBLC for one facility's melt shop opacity, at Nucor Corporation in Marion, OH, where 0 percent melt shop opacity was determined to be BACT. The Ohio Nucor facility was added to the EAF opacity data. bringing the total to 34 EAF facilities with opacity data.

      An analysis of the melt shop opacity data for 34 EAF facilities showed that for 9 facilities the maximum in the range in melt shop opacity was greater than 3 percent but less than or equal to 6 percent opacity, the NSPS limit; 7 facilities had a range in melt shop opacity where the maximum opacity was less than or equal to 3 percent but greater than 0 percent; and for 15 facilities, the data for melt shop opacity was all 0 percent. For three facilities (Steel Dynamics-Butler-IN, Steel Dynamics-Columbia City-IN, and Steel Dynamics-Pittsboro-IN), the melt shop had no roof monitors; therefore, opacity was not able to be measured from the melt shop roof, bringing the total EAF facilities with melt shop opacity data to 31 facilities. Table 6 shows the facilities with melt shop opacity data, group by maximum opacity level (0, 3, and 6 percent) in the test data, and the year(s) of the test reports, from 2005 to 2011. Table 7 shows the range of melt shop opacity test scores for 31 EAF facilities in test reports (2005-2011), with test minimum, average, and maximum. Appendix D contains an Excel(TM) file with the compiled 2010 section 114 request opacity test data for the 31 facilities in the EPA opacity dataset.

        Table 6. Melt Shop Opacity in 31 EAF Test Reports (2005-2011)
                       from 2010 CAA Section 114 Request
                                   Facility
                                     Count
                           Facility Name-City- State
                                    Maximum
                                  Melt Shop
                                  Opacity (%)
                                  Data Years
                                       1
AK Steel-Butler-PA
                                    0.000%
2008
                                       2
AK Steel-Mansfield-OH
                                    0.000%
2010
                                       3
CMC-Birmingham-AL
                                    0.000%
2009
                                       4
CMC-Cayce-SC
                                    0.000%
2008
                                       5
CMC-Mesa-AZ
                                    0.000%
2010
                                       6
Gerdau-Charlotte-NC
                                    0.000%
2008, 2010
                                       7
Gerdau-Jackson-MI
                                    0.000%
2014
                                       8
North American Stainless-Ghent-KY
                                    0.000%
2010, 2011
                                       9
Nucor-Crawfordsville-IN
                                    0.000%
2005, 2007, 2010
                                      10
Nucor-Huger-SC
                                    0.000%
2007, 2008, 2010
                                      11
Nucor-Jewett-TX
                                    0.000%
2005
                                      12
Nucor-Marion-OH
                                    0.000%
2010
                                      13
SSAB-Axis-AL
                                    0.000%
2007, 2008, 2010
                                      14
Timken-Faircrest-OH
                                    0.000%
2008, 2011
                                      15
Timken-Harrison-OH
                                    0.000%
2010, 2011
                                       1
CMC-Seguin-TX
                                 0.000 % <= 3
2010
                                       2
Gerdau-Jackson-TN
                                 0.000 % <= 3
2006, 2010
                                       3
Gerdau-Knoxville-TN
                                 0.000 % <= 3
2009, 2010
                                       4
Gerdau-St. Paul-MN
                                 0.000 % <= 3
2009, 2010
                                       5
Gerdau-Wilton-IA
                                 0.000 % <= 3
2010
                                       6
Nucor-Darlington-SC
                                 0.000 % <= 3
2008, 2010
                                       7
Nucor-Plymouth-UT
                                 0.000 % <= 3
2005, 2006, 2007
                                       1
Allegheny-Brackenridge-PA
                                3 < % < 6
2006, 2011
                                       2
Allegheny-Latrobe-PA
                                3 < % < 6
2011
                                       3
Gerdau-Beaumont-TX
                                3 < % < 6
2006, 2007, 2008, 2009, 2010
                                       4
Gerdau-Cartersville-GA
                                3 < % < 6
2008, 2010
                                       5
Gerdau-Jacksonville-FL
                                3 < % < 6
2008, 2009, 2010
                                       6
Nucor-Blytheville-AR
                                3 < % < 6
2005, 2006, 2007, 2008, 2009
                                       7
Nucor-Cofield-NC
                                3 < % < 6
2010
                                       8
Nucor-Norfolk-NE
                                3 < % < 6
2005, 2006, 2007, 2008, 2009, 2010
                                       9
Sterling Steel-Sterling-IL
                                3 < % < 6
2008
                                      31
                                     Total

    Table 7. Range of Melt Shop Opacity in 31 EAF Test Reports (2005-2011)
                       from 2010 CAA Section 114 Request
                                     Count
                                  Facility ID
                          Melt Shop Opacity (Percent)
                          Range of 6-Minute Readings

                                Minimum Percent
                                Average Percent
                                Maximum Percent

                                       1
AKS-Butler-PA
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       2
AKS-Mansfield-OH
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       3
CMC-Birmingham-AL
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       4
CMC-Cayce-SC
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       5
CMC-Mesa-AZ
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       6
Ger-Charlotte-NC
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       7
Ger-Jackson-MI
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       8
NAS-Ghent-KY
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       9
Nuc-Crawfordsville-IN
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      10
Nuc-Huger-SC
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      11
Nuc-Jewett-TX
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      12
Nuc-Marion-OH
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      13
SSAB-Axis-AL
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      14
Tim-Faircrest-OH
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                      15
Tim-Harrison-OH
                                     0.000
                                     0.000
                                     0.000
                        0.000% opacity during all tests
                                       1
Nuc-Darlington-SC
                                     0.000
                                     0.001
                                      0.4
                     0% <= opacity during all tests <=3%
                                       2
Ger-Knoxville-TN
                                     0.000
                                     0.01
                                      1.0
                     0% <= opacity during all tests <=3%
                                       3
Ger-StPaul-MN
                                     0.000
                                     0.02
                                      2.5
                     0% <= opacity during all tests <=3%
                                       4
Nuc-Plymouth-UT
                                     0.000
                                     0.05
                                      2.0
                     0% <= opacity during all tests <=3%
                                       5
CMC-Seguin-TX
                                     0.000
                                     0.10
                                      1.0
                     0% <= opacity during all tests <=3%
                                       6
Ger-Wilton-IA
                                     0.000
                                     0.10
                                      1.0
                     0% <= opacity during all tests <=3%
                                       7
Ger-Jackson-TN
                                     0.000
                                     0.20
                                      2.5
                     0% <= opacity during all tests <=3%
                                       1
Ger-Jacksonville-FL
                                       0
                                     0.10
                                      36
                    3% < opacity during all tests <6%
                                       2
Alle-Brackenridge-PA
                                       0
                                     0.20
                                      5.0
                    3% < opacity during all tests <6%
                                       3
Nuc-Cofield-NC
                                       0
                                     0.20
                                      5.0
                    3% < opacity during all tests <6%
                                       4
Alle-Latrobe-PA
                                       0
                                     0.30
                                      4.0
                    3% < opacity during all tests <6%
                                       5
Nuc-Blytheville-AR
                                       0
                                     0.30
                                      5.0
                    3% < opacity during all tests <6%
                                       6
Nuc-Norfolk-NE
                                       0
                                     0.30
                                      6.0
                    3% < opacity during all tests <6%
                                       7
Ger-Beaumont-TX
                                       0
                                     0.50
                                      7.0
                    3% < opacity during all tests <6%
                                       8
Ger-Cartersville-GA
                                       0
                                     0.80
                                      6.0
                    3% < opacity during all tests <6%
                                       9
Ster-Sterling-IL
                                       0
                                      1.2
                                      6.0
                    3% < opacity during all tests <6%
                                      31
                            Overall Average Opacity
                                       0
                                     0.14
                                      2.9

 5.0	FACILITIES WITH 0 PERCENT MELT SHOP OPACITY AS FACILITY AVERAGE

      The total facility PM emissions for EAF facilities achieving 0 percent melt shop opacity as a facility average were compiled to support cost analyses and recommendations for BSER that are part of the technology review for the EAF NSPS. Table 8 shows the total facility mass of PM emitted per mass of steel produced (lb/ton) as a facility average for the 13 facilities with 0 percent melt shop opacity.

 6.0	EMISSION REDUCTIONS TO 0 PERCENT MELT SHOP OPACITY

 6.1	Estimates of Predicted Actual PM Emissions Reductions To 0 Percent Melt Shop Opacity

      Estimates of the mass of PM emissions at various opacity levels are difficult to make and, if attempted, would involve many variables relating to the physical and optical characteristics of the specific PM at each facility. In order to estimate actual emission reductions with 0 percent melt shop opacity for the purposes of the EAF NSPS technology review, estimates of PM emissions were used that were developed as part of the BSER analysis described in the Cost Memorandum.[1]

      For the purpose of estimating actual emission reductions with a 0 percent melt shop opacity standard, the average facility melt shop opacity of the EAF data found in the 2010 CAA section 114 data, at 0.14 percent, can be used, as described below. In the Cost Memorandum,1 estimates of the melt shop PM emissions and reductions was developed for a medium-sized EAF facility estimated to produce 542,500 tons per year (tpy) steel and emitting PM from the melt shop roof vents at the current 6 percent opacity limit in the EAF NSPS. Table 9 shows these data.

      The estimate of 700 tpy PM emitted from the melt shop roof vent of a medium-size facility with 6 percent opacity can be used to estimate the melt shop PM emissions for a medium-size facility with 0.14 percent opacity, by proportion of the melt shop opacities (0.14% / 6% x 700 tpy = 16.3 tpy), and then also for small (190,855 tpy steel) and large (1,237,250 tpy steel) EAF facilities,[5] by proportion of the steel production. Linearity is assumed between PM and opacity, and between PM and steel production, at the various levels of melt shop roof vent opacity. This results in actual emission estimates for small, medium, and large facilities are 5.7, 16, and 37 tpy PM, respectively. Table 9 shows the results of this analysis for a medium size facility. Table 10 for net amount of PM reduced for other size facilities.

Table 8. Total Facility EAF Baghouse PM Emission Rate (lb/ton) for Facilities with
0 Percent Melt Shop Opacity At All Times During Testing from 2010 CAA Section 114 Request
                                    lb/ton
                                     Rank
                            Facility Name/Location
                             Baghouse PM Sources
                                (No. Baghouses)
                                    Number
                                    EAF/AOD
                                Total Baghouse
                      Average Facility Melt Shop Opacity

                                 PM Emissions

                                   (lb/ton)

                                       1
Timken-Faircrest-OH
EAF/melt shop baghouse (1)
                                       1
                                    1.3E-02
                                    0.000%
                                       2
CMC-Mesa-AZ
EAF/melt shop baghouse (1)
                                       1
                                    1.3E-02
                                    0.000%
                                       3
Nucor-Crawfordsville-IN
EAF/melt shop baghouses (2)
                                       2
                                    1.6E-02
                                    0.000%
                                       4
Gerdau-Charlotte-NC
EAF/melt shop baghouse (1)
                                       1
                                    2.3E-02
                                    0.000%
                                       5
AK Steel-Butler-PA
EAF and AOD baghouses (3)
                                       3
                                    3.1E-02
                                    0.000%
                                       6
Timken-Harrison-OH
EAF/melt shop baghouses (2)
                                       2
                                    3.6E-02
                                    0.000%
                                       7
Nucor-Huger-SC
EAF/melt shop baghouses (2)
                                       2
                                    5.2E-02
                                    0.000%
                                       8
Gerdau-Jackson-MI
EAF/melt shop baghouse (1)
                                       2
                                    5.4E-02
                                    0.000%
                                       9
CMC-Birmingham-AL
EAF/melt shop baghouses (2)
                                       1
                                    5.5E-02
                                    0.000%
                                      10
CMC-Cayce-SC
EAF/melt shop baghouse (1)
                                       1
                                    6.4E-02
                                    0.000%
                                      11
Nucor-Jewett-TX
EAF/melt shop baghouse (1)
                                       1
                                    1.2E-01
                                    0.000%
                                      12
AK Steel-Mansfield-OH
EAF/melt shop baghouses (2)
                                       2
                                    1.4E-01
                                    0.000%
                                      13
North American Stainless-Ghent-KY
EAF/AOD/melt shop baghouses (4)
                                       2
                                    1.6E-01
                                    0.000%

Table 9. Estimate of PM and PM2.5 Reduced for a Typical Medium-Sized Facility[1] with
0 Percent Melt Shop Roof Vent Opacity from Allowable and Actual Opacity Baselines
                                    Source
                              PM Emissions (tpy)
               6% Opacity Baseline for Medium-Sized Facility[1]
                        PM2.5 Emissions Reduced (tpy) 2
                              PM2.5/ PM factor[2]

                         6% Opacity Allowable Baseline
                         0.14% Opacity Actual Baseline

                                   Increase
                                   Decrease

Additional PM exiting EAF baghouse (controlled)
                                      31

                                      12
                                     0.28
                                     0.385
EAF roof vent emissions (uncontrolled)

                                      731
                                      159
                                      3.7
                                     0.218
Net amount of PM/PM2.5 reduced

                                      700
                                      147
                                      3.4
                                      NA
[1] For a typical medium-sized facility producing 542,500 tpy steel. The PM estimates are explained in detail in the Cost Memorandum.1 For small and large facilities, actual PM2.5 emission reductions are estimated at 1.2 and 7.8 tpy, respectively.
[2] PM2.5 estimated using a factor of 0.0231 PM2.5/PM, derived from AP-42[8] data, described in Section 6.2. See also Appendix E. NA = Not applicable.

Table 10. Allowable and Predicted Actual PM Emissions and Reductions at EAF Facilities
   Achieving 0 Percent Melt Shop Opacity from 6% and 0.14% Opacity Baselines
                                 Facility Size
                          Melt Shop Opacity (percent)
                         Facility Production (tpy)[1]
Emissions/Reductions (tpy) from Reducing Melt Shop Opacity to 0 Percent, by Facility Size

                                  PM Baseline
                               PM Reductions[3]
                                   PM2.5[3]
                     Allowable Emissions and Reductions[2]
Small facility
                                      6.0
                                    190,855
                                      246
                                      246
                                      5.7
Medium facility
                                      6.0
                                    542,500
                                      700
                                      700
                                      147
Large facility
                                      6.0
                                   1,237,250
                                     1,596
                                     1,596
                                      37
                        Actual Emissions and Reductions
Small facility
                                     0.14
                                    190,855
                                      5.7
                                      5.7
                                      1.2
Medium facility
                                     0.14
                                    542,500
                                      16
                                      16
                                      3.4
Large facility
                                     0.14
                                   1,237,250
                                      37
                                      37
                                      7.8
[1] From Steel Manufacturers Association data of EAF production in 2017.
[2] See the Cost Memorandum[1] for a derivation of the baseline PM emission estimates from melt shop roof vents at 6 percent opacity (as per 40 CFR part 60, subpart AAa).
[3] PM2.5 estimated using a factor of 0.0231 PM2.5/PM, derived from AP-42[8] data, described in Section 6.2. See also Appendix E.

 6.2	Estimates of Actual PM2.5 Emission Reductions To 0 Percent Melt Shop Opacity

      The estimates of PM emissions reductions estimated above can be used to estimate the PM2.5 portion of the PM emission reductions, as discussed below. For the EAF model plant analysis in the Cost Memorandum,1 the PM baghouse emissions from a medium-sized facility (542,500 tpy steel) shop opacity under the new standard of 0.16 lb/ton (BSER limit for baghouses) is 43 tpy for a medium-sized facility producing 542,500 tpy steel (0.16 x 542,500 / 2000). Emissions from a baghouse where there is 6 percent melt shop opacity are 0.044 lb/ton, which is 12 tpy PM emissions for medium-sized facility (0.044 x 542,500 / 2000). This results in an additional 31 tpy (43 tpy minus 12 tpy) emitted from the baghouse at a 0 percent melt shop opacity facility.

      However, 731 tpy of PM are prevented from being emitted when 6 percent opacity is reduced to 0 percent opacity. If 0 percent opacity is only required during melting&refining, and melt shop opacity remains at 6% for charging and refining, then only 629 tpy of PM are prevented from being emitted with the final rule. Therefore, a net of 598 tpy PM is reduced (629 -31 tpy).

      A PM2.5/PM ratio for controlled and uncontrolled sources was developed from an average of the AP-42[,] emission factors for similar controlled and uncontrolled sources in the steel sector. See Appendix E for the AP-42 emissions factors used to develop PM/PM2.5 ratios for the EAF data. The uncontrolled PM2.5/PM ratio of 0.218 PM2.5/PM was used to estimate PM2.5 emissions in the 598 tpy of PM from above estimated to be emitted from the melt shop roof vents. The controlled PM2.5/PM ratio of 0.385 PM2.5/PM was used to estimate PM2.5 emissions in the 31 tpy of PM from above estimated to be emitted from the baghouse. The results are 159 tpy PM2.5 emitted from the melt shop and 12 tpy PM2.5 emitted from the baghouse for a net of 147 tpy (159 - 12 tpy) PM2.5 controlled when 700 tpy PM is reduced when a 0 percent melt shop opacity standard is implemented from a 6 percent standard.

      For medium-sized facilities achieving 0.14 percent opacity in actual performance, the emissions above can be reduced by a factor of 0.14/6 to produce a net of 3.4 tpy predicted actual PM2.5 emissions reduced (3.71  -  0.28 tpy PM2.5) with a 0 percent melt shop opacity standard. Similarly, for small and large facilities, actual PM2.5 emission reductions are estimated at 1.2 and 7.8 tpy, respectively. Table 10 shows the allowable and predicted actual PM/PM2.5 emissions and reductions at three generic sizes of EAF facilities achieving 0 percent melt shop opacity from baselines of 6 percent and 0.14 percent opacity.

 7.0	PM EMISSION REDUCTIONS TO 0/6 PERCENT MELT SHOP OPACITY

 7.1	Estimate of PM Reductions with 0/6% Melt Shop Opacity

      Charging and tapping periods are estimated to have high PM emissions, although no data are available to the EPA to confirm this information obtained through industry comments on the proposed EAF rule. In the final rule for 40 CFR part 60, subpart AAb, EAF facilities will be permitted to retain a 6 percent opacity limit during charging and tapping while reducing to 0 percent opacity during melting&refining. The following describes the assumptions used to estimate the emissions reductions when opacity is reduced from 6 percent opacity under 40 CFR part 60, subpart AAa to 0 percent opacity during melting&refining only, under 40 CFR part 60, subpart AAb, and retaining the 6 percent during charging and tapping as in the current NSPS 40 CFR part 60, subpart AAa. Table 11 summarizes the calculations and assumptions used, which are also described below.

      In order to estimate the emissions and reductions of PM when opacity is reduced to 0 percent during melting&refining and remains at 6 percent during charging and tapping, a number of assumptions need to be made. These assumptions are not intended to produce an exact estimate of emissions and reductions, which could only be made if the operation of each individual EAF was known. The EAFs are known to operate 24  hours per day and produce steel in batches. For this analysis, the assumption is made that each "heat" or batch is 3 hours based on the description in AP-42,[8] which states that EAF heats range from about 1.5 to 5 hours to produce carbon steel. For this analysis, three hours per heat was assumed, with 15 minutes assumed for charging and 15 minutes for tapping. For a total of 3.5 hours tap-to-tap. Based on this amount of time estimated per heat, there were 6.9 heats estimated per day. This breakdown also amounts to 3.4 hours per day when the EAF is either being charged or tapped and 20.6 hours when the EAF is in the melting&refining stage. The breakdown amounts to 14 percent of the day during charging and tapping and 86 percent during melting&refining. Using estimates of PM emissions during the time an EAF is operating with 6 percent melt shop opacity, as described above, and the estimate of 86 percent reduction in PM, emissions were estimated for the control scenario of 0 percent opacity during melting&refining and 6 percent during charging and tapping. The resulting emissions and reductions in tpy are shown in Table 11 where, for example, a medium-size facility, has 600 tpy PM reduced from a baseline of 700 tpy and a controlled level of 100 tpy PM emissions.

 7.2	Estimate of PM2.5 Reductions with Reduction in Melt Shop Opacity
      The estimated emissions of PM and PM2.5 with 0 percent opacity during melting&refining and 6 percent during charging and tapping are shown in Table 12 from both an allowable emissions baseline of 6 percent opacity at all times and actual estimated emissions level of 0.14 percent opacity during melting&refining and 6 percent during charging and tapping. These estimates were developed using the parameters describe above where the reduced emission levels of PM are estimated as 14 percent of the baseline emissions of 6 percent opacity at all times and PM reductions are 86 percent of the PM reduced with 0 percent at all times. The PM2.5 emissions were calculated as in Section 6.2 above and described in Appendix E, using the controlled PM2.5/PM ratio of 0.385 PM2.5/PM derived from an average of the AP-42 emission factors for similar controlled and uncontrolled sources in the steel sector.[9][,][Error! Bookmark not defined.]

Table 11. Estimated Operating Hours During Phases of EAF/AOD Operation (Melting&Refining, Charging, and Tapping).
                                   Category
                                 Facility Size
                                     Value
                                     Units
                         Descriptions and Assumptions
Assumptions
all
                                      24
hours
operation

                                       3
hours
per heat[1]

                                      15
minutes
each per charge and per tap[2]

                                      6.9
heats/day
calculated

                                      3.4
hr/day
charging, tapping
calculated

                                      14%
day
charging, tapping
calculated

                                     20.6
hr/day
at 0% opacity, melting&refining
calculated

                                      3.4
hr/day
at 6% opacity, charging, tapping
calculated

                                      86%
of day
at 0% opacity, melting&refining
calculated

                                      14%
of day
at 6% opacity, charging, tapping
calculated
No allowance for charging, tapping opacity
small
                                      246
tpy PM
PM reduced from 6% opacity to 0%
24 hours operation

medium
                                      700
tpy PM
PM reduced from 6% opacity to 0%
24 hours operation

large
                                     1,596
tpy PM
PM reduced from 6% opacity to 0%
24 hours operation
Allowance for charging, tapping opacity
small
                                     0.00
tpy PM
PM reduced from 6% opacity to 6%
24 hours operation

medium
                                     0.00
tpy PM
PM reduced from 6% opacity to 6%
24 hours operation

large
                                     0.00
tpy PM
PM reduced from 6% opacity to 6%
24 hours operation
Melting&refining at 6% opacity
small
                                      211
tpy PM
PM emissions at 6% opacity
20.6 hr/day

medium
                                      600
tpy PM
PM emissions at 6% opacity
20.6 hr/day

large
                                     1,368
tpy PM
PM emissions at 6% opacity
20.6 hr/day
EAF emissions reduced at 0% opacity melting&refining, and % opacity charging, tapping
small
                                      211
tpy PM
PM reduced with 0% melting& refining, and 6% opacity charging and tapping
3.4 hours operation at 6% opacity and 20.6 hr at 0%

medium
                                      600
tpy PM

large
                                     1,368
tpy PM

EAF emissions after reducing melting&refining to 0 percent
small
                                      35
tpy PM
14 percent of no control/baseline 6% emissions

medium
                                     100
tpy PM
14 percent of no control/baseline 6% emissions

large
                                     228
tpy PM
14 percent of no control/baseline 6% emissions
[1] Assumes 3 hours per heat as an average value (AP-42[Error! Bookmark not defined.]). AP-42: "The production of steel in an EAF is a batch process. Cycles, or "heats", range from about 1.5 to 5 hours to produce carbon steel."
[2] Assumes 15 minutes each for charging and tapping for a total of approximately 3.4 hours per day charging and tapping at 6% opacity and 20 hours per day at 0 opacity.

Table 12. Allowable and Predicted Actual PM Emissions and Reductions at EAF Facilities Achieving 0/6%[1] Melt Shop Opacity from 6% and 0.14% Opacity Baselines
                                 Facility Size
                          Melt Shop Opacity (percent)
                    Estimated Facility Production (tpy)[2]
                        Emissions and Reductions (tpy)

                             PM Baseline Emissions
                     PM Reductions to 0/6% Opacity[1],[3]
                   PM[2.5] Reductions to 0/6% Opacity[1,][3]

          Baseline Allowable Emissions of 6% Opacity at All Times[4]
Small facility
                                       6
                                    190,855
                                      246
                                      212
                                      4.9
Medium facility
                                       6
                                    542,500
                                      700
                                      602
                                      14
Large facility
                                       6
                                   1,237,250
                                     1,596
                                     1,373
                                      32
                        Actual Emissions and Reductions
Small facility
                                     0.14
                                    190,855
                                      5.7
                                      4.9
                                      1.0
Medium facility
                                     0.14
                                    542,500
                                      16
                                      14
                                      3.0
Large facility
                                     0.14
                                   1,237,250
                                      37
                                      32
                                      6.7
1 0 percent opacity during melting&refining and 6 percent during charging and tapping.
[2] From Steel Manufacturers Association data of EAF production in 2017.[5]
[3] Charging and tapping is estimated to be approximately 3.5 hours/day assuming 7 heats per day, 3 hours per heat, 30 minutes total charging and tapping per heat.
[4] See the Cost Memorandum[1] for a derivation of the baseline PM emission estimates from melt shop roof vents at 6 percent opacity (current NSPS).

 8.0 REFERENCES

U.S. Environmental Protection Agency. Compilation of Emission Factors, Publication AP-42. Section 12.5 Iron and Steel Production. U.S. Environmental Protection Agency, Research Triangle Park, NC. July 1995.

U.S. Environmental Protection Agency, Research Triangle Park, NC. Evaluation of PM2.5 Emissions and Controls at Two Michigan Steel Mills and a Coke Oven Battery. Final Report. Work Assignment 4-12 under EPA Contract No. 68-D-01-073 with RTI International, Research Triangle Park, NC. U.S. Environmental Protection Agency, Research Triangle Park, NC. February 2006.

U.S. Environmental Protection Agency. "Cost Analyses to Determine BSER for PM Emissions and Opacity from EAF Facilities." D.L. Jones, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina, and G.E. Raymond, RTI International, Research Triangle Park, North Carolina. U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina. May 1, 2023. (Docket Number EPA-OAR-HQ-2002-0049).

                                  APPENDIX A

                      EAF NSPS Compiled PM Test Data from
                      2010 Section 114 Request Responses

                    [Excel file with EAF NSPS PM Test Data]

                                  APPENDIX B

             EAF NSPS PM Test Data for Emission Factor Development
                    from 2010 Section 114 Request Responses

    [Excel file with EAF NSPS PM Test Data for Emission Factor Development]

                                  APPENDIX C

         2005 CAA Section 114 Request Response Data for 12 Facilities
       with Sufficient Total Facility Data to Calculate lb/ton Emissions

  [Excel file with EAF NESHAP PM Test Data Used to Develop lb/ton Emissions]

                                  APPENDIX D

                        EAF NSPS Opacity Test Data from
                      2010 Section 114 Request Responses

                 [Excel file with EAF NSPS Opacity Test Data]

                                  APPENDIX E

                    PM/PM2.5 Factors Developed for EAF Data

                                   PM Source
                           Ratio PM2.5 to PM-Filter
                                   Source[1]

                                 Uncontrolled
                                  Controlled

BOF charging fugitives (uncontrolled)
                                     0.22

                                   AP-42[8]
BOF charging baghouse (controlled)

                                     0.22
                                     AP-42

BOF tapping fugitives (uncontrolled)
                                     0.37

                                     AP-42
BOF tapping baghouse (controlled)

                                     0.16
                                     AP-42

Desulfurization fugitives (uncontrolled)
                                     0.11

                                     AP-42
Desulfurization baghouse (controlled)

                                     0.42
                                     AP-42

Pushing fugitives (uncontrolled)
                                     0.17

                                     AP-42
Coke pushing baghouse (controlled)

                                     0.74
                                     AP-42

Uncontrolled ratio (average)
                                     0.218

Controlled ratio (average)

                                     0.385

[1] As cited in "Evaluation of PM2.5 Emissions and Controls at Two Michigan Steel Mills and a Coke Oven Battery." Final Report. Work Assignment 4-12 under EPA Contract No. 68-D-01-073 by RTI International, Research Triangle Park, NC. U.S. Environmental Protection Agency, Research Triangle Park, NC. February 2006.[8]