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MEMORANDUM TO: David Putney , E nvironmental P rotection A gency (EPA) FROM: David Green , RTI, International DATE: November 4, 2011 SUBJECT: Draft Development of the RTR Emissions Dataset for the Primary Aluminum Re duction

Source Category The purpose of this memorandum is to document the technical approach and rationale used to assign hazardous air pol lutant (HAP) emissions data for primary aluminum reduction facilities . This work is being performed pursuant to section 112(f) of the Clean A ir Act as part of the residual risk assessment for facilities that are subject to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Primary Aluminum Reduction Plants ( 40 CFR p art 63, s ubpart LL ). I . Source - Specific Emissions Three mai n HAP are emitted from the Primary Aluminum Re duction source category: Polycyclic organic matter (POM) , hydrogen fluoride (HF), and carbonyl sulfide (COS). POM is emitted from potlines, anode bake furnaces, paste production plants, and pitch storage tan ks. HF is emitted from potlines and anode bake furnaces. COS is emitted from potlines. Potline emissions are divided between the primary emissions (i.e., the exhaust of the primary control system ) and secondary emissions (i.e., the exhaust from the roof ve nts of the potrooms ) . II . Compound Specific Emissions POM is listed as a HAP compound group , however residual risk modeling requires that POM be allocated to specific organic compounds that are associated with compound - specific risk factors. No recent data a re available on the specific compounds that compose POM emissions. POM emission factors for specific compounds have been estimated on the basis of speciation determined from testing of a limited number of aluminum plants in 1994, and applied to estimated i ndividual POM compound emissions for modeling . Total fluoride (TF) is a surrogate for HF, therefore risk modeling requires emissions estimates for HF. TF is made up of HF and particulate fluoride. Limited data are available on the relative contributions of these fractions. Test data suggest that typically about 50% of the TF is made up of HF, and this has been assumed in cases where there are no data for HF emissions. III . Limitations of Data Availability There are two main categories of potlines : prebake an d Soderberg . Under the 1997 NESHAP, POM emissions are regulated from Soderberg potlines but not from prebake potlines. Thus, POM emissions from prebake potlines are not routinely measured. Prebake potlines are in use at 12 of the 14 primary aluminum reduction facilities, and 11 of the 12 currently operating facilities. POM emissions from paste production plants and new pitch storage tanks are regulated by equipment standard s , but the 1997 NESHAP does not require emissions testing and there are no current data on paste production plant or new pitch storage tank POM emissions.

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COS emissions are not regulated under the 1997 NESHAP. Thus, COS emissions are not routinely measured and limited COS emissions test data exist. In an effort to gather more information on emissions from the Primary Aluminum Re duction source category, an information collection request (ICR) was sent by the EPA to all operators of primary aluminum reduction plants in April, 2011. The associated responses were receiv ed in July, 2011. IV . Collocated Sources Most primary aluminum facilities (i.e., 10 of the 15 facilities subject to 40 CFR part 63, subpart LL ) have collocated secondary aluminum production sources. These collocated sources were not included in the risk asse ssment for th e Primary Aluminum Re duction source category. The upcoming risk and technology review project for the Secondary Aluminum Production source category will include residual risk modeling for primary aluminum reduction affected sources which are c ollocated at secondary aluminum production facilities. V . Development of Emission Rates for Modeling 1 . POM Emissions from Potlines Estimates of speciated POM emissions from prebake potlines were developed using emission factors calculated from reports of two performance tests conduc ted at prebake plants in 1994. T hese emission factors were calculated from the average emission factor, in pounds HAP per ton aluminum produced from the two tests. In cases where the concentrations were below the detection limit fo r a specific compound, an emission rate was calculated based on one - half of the reported detection limit. The average emission factors were applied to the capacity of the plant in 2010 (as reported by the USGS, and corrected by the Aluminum Association). E stimated actual emissions from the outlet of the control device and the roof vents are given in Tables 1 and 2. The emission factors used in the calculation are shown in each table. Tables 1 and 2 reflect the total actual potline emissions for each facilit y. For modeling purposes, the emissions from the control device outlet were evenly divided between the associated stacks. The emissions from the roof vents were evenly divided between the associated roof vents. No attempt was made to proportion emissions t o specific emission points in cases where plants had non - identical (length, number of pots, aluminum capacity) pot line s. Since there is no POM emission limit for this affected source “allowable emissions” is not defined . After an analysis of data on p rimar y a luminum p roduction emissions gathered from the 2002 National Emissions Inventory (NEI), the 2005 NEI , responses to the April, 2011 ICR referenced above , and other information gathered on the primary aluminum industry, allowable emissions for modeling pu rposes were developed by multiplying the estimated actual emissions by 1.5. Estimates of speciated POM emissions from Soderberg potlines were developed using emission factors calculated from reports of two performance tests conducted at Soderberg plants i n 1994. These emission factors were calculated from the average emission factor, in pounds HAP per ton aluminum produced from the two tests. In cases where specific concentrations were below the detection limit for a specific compound, an emission rate was calculated based on one - half of the reported detection limit. The average emission factors were applied to the capacity of the plant in 2010 (as reported by the USGS, and corrected by the Aluminum Association). Estimated actual emissions from the outlet o f the control device and the roof vents are given in Tables 3 and 4. The emission factors used in the calculation are shown in each table. Tables 3 and 4 reflect the total actual potline emissions for each facility. For

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modeling purposes, the emissions from the control device outlet were evenly divided between the associated stacks. The emissions from the roof vents were evenly divided between the associated roof vents. No attempt was made to proportion emissions to speci fic emission points in cases where plants had non - identical (length, number of pots, aluminum capacity) pot line s. Note that the Columbia Falls facility closed in 2009 and has not operated at capacity since 1999. Therefore, modeling was not performed for es timated actual emissions from the Columbia Falls facility . After an analysis of data on primary aluminum production emissions gathered from the 2002 NEI, the 2005 NEI, responses to the April, 2011 ICR referenced above, and other information gathered on the primary aluminum industry, allowable emissions for the Massena East plant for modeling purposes were developed by multiplying the estimated actual emissions by 1.5 and allowable emissions for the Columbia Falls plant for modeling purposes were developed b y multiplying the estimated actual emissions by 1. 9 . 2 . HF Emissions from Potline s and Anode Bake Furnace s Allowable emissions of T F were calculated from the allowable emission limits for anode bake furnaces and for each potline type and assuming facility operation at capacity. In one case (Alumax of South Carolina, located in Mt. Holly, SC) a more stringent potline limit imposed by State regulations was applied. Allowable HF emissions were estimated to be 1⁄2 of the al lowable TF emissions, unless data provided in the responses to the April, 2011 ICR indicated otherwise. The a llowable HF emissions are summarized in Table 5. Actual HF emissions were obtained from information provided in response to the April, 2011 ICR, wh en available. When actual HF emission data were not available from an ICR response, those emissions were estimated to be two thirds of the allowable emissions. Actual and allowable potline HF emissions were split between control device stacks and roof vent s in accordance with information provided in the responses to the April, 2011 ICR, when available. Where no information was available , all actual and allowable potline HF emissions were assigned to roof vents because of the high degree of control (estimated to be about 99%) achieved by the associated controls (typically dry alumina scrubbers with baghouses) . Limited data from ICR responses are summarized in Table 6. For modeling purposes, the emissions from the control device outlet were evenly div ided between the associated stacks. The emissions from the roof vents were evenly divided between the associated roof vents. No attempt was made to proportion emissions to specific emission points in cases where plants had non - identical (length, number of pots, aluminum capacity) pot line s. 3 . COS Emissions from Potlines Emissions of COS are not regulated under the 1997 NESHAP. However, actual COS emissions were available for some plants in updates to the NEI while o ther plants reported COS emission s data in their response to the April, 2011 ICR or to other information requests from the EPA. Where no reported COS emissions data were available, actual COS emissions were estimated from the industry average emission factor of 2.85 pounds COS per ton of aluminum p roduced , which was calculated from the average of those plants for which data were available. Once again, since COS is not regulated under the 1997 NESHAP, allowable emissions are not defined . A llowable emissions for modeling purposes were estimated to be equal to the actual emissions. COS emissions were assumed to be emitted from the control device stack reflecting the fact that COS is not controlled by the associated potline controls (typically dry alumina scrubbers with baghouses) and that the potline fu me capture system captures most ( typically reported in excess of 95%) of the exhaust from the pot line s. For modeling purposes, the emissions from the control device outlet were evenly divided between the associated stacks. Estimated COS emissions used in modeling are shown in Table 7.

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4 . POM Emissions from Anode Bake Furnace s No recent compound specific data are available for POM emissions from anode bake furnaces. Estimates of speciated POM emissions from anode bake furnaces were developed using e mission factors calculated from reports of two performance tests conducted at prebake plants in 1994. These emission factors were calculated from the average emission factor, in pounds HAP per ton aluminum produced from the two tests. In cases where specif ic concentrations were below the detection limit for a specific compound, an emission rate was calculated based on one - half of the reported detection limit. The average emission factors were applied to the production capacity of the plant in 2010 (as repor ted by the USGS, and corrected by the Aluminum Association) to estimate actual anode bake furnace POM emissions. The emission factors used for calculation of actual emissions and the estimated actual emissions are summarized in Table 8 . Once again, based o n an analysis of available data, allowable anode bake furnace POM emissions were developed by multiplying the estimated actual emissions by 1.5 for modeling purposes. 5 . POM Emissions from Paste Production Plants Estimates of actual POM emissions from paste production plants were based on emission factors cited in "Locating and Estimating Air Emissions from Sources of Polycyclic Organic Matter," EPA - 454/R - 98 - 014 (July 1998). The emission factors , which assume control by a dry coke scrubber, and the paste pro duction actual emissions estimates are summarized in Table 9 . These emissions estimates are based on 2010 aluminum production capacity in tons (as reported by the USGS, and corrected by the Aluminum Association) , multiplied by a n industry average factor of 0.57 tons of paste consumed per ton of aluminum produced , multiplied by the emission factors referenced above . Once again, based on an analysis of available data, allowable POM emissions were developed by multiplying estimated actual emissions by 1.5. 6 . POM Emissions from Pitch Storage Tank s There are no data available on POM emissions from pitch storage tanks. Actual pitch storage tank emissions were estimated based on the following assumptions: 1) a factor of 0.57 tons of green anode per ton of aluminum produced (the industry average value provided by The Aluminum Association) ; 2) that 22% of anode paste is pitch (the industry average value provided by The Aluminum Association); 3) a calculated vapor pressure of oxidized asphalt at 300 degrees F ahrenheit (assumed to approximate pitch at that temperature , based on available data ) of 0.0034 atmospheres (0.34 percent); 4) that 35% of the organic vapors are HAPs (an estimate based on available data); 5) the organic HAP profile is similar to that at t he inlet to the primary control device for a Soderberg potline (specifically, as determined from testing conducted at the Kaiser - Tacoma Soderberg facility); and 6) the volume of exhaust emitted from the pitch storage tank is equal to the volume of pitch pu mped into the tank. Estimates of pitch consumption and actual HAP emissions are listed in Table 1 0 . Estimates of actual compound - specific POM are listed in Table 1 1 . Allowable pitch storage tank emissions were assumed to be equal to estimated actual pitch storage tank emissions. VI . QA/QC Facilities were asked to provide stack and fugitive parameters and locations for potline stacks, potline roof vents and anode bake furnaces. Potline stack locations and roof vent dimensions were visually reviewed using Googl e Earth. Locations of paste production plants, and pitch storage tanks were estimated based on aerial views from Google Earth. Adjustments were made for coordinates based on

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these visual evaluations. Potline roof vent lengths, areas and orientations were p lotted in Google Earth and corrected as necessary. Where stack parameters were provided by facilities these were used for modeling. When stack parameters were unavailable, default values from the NEI were used for modeling. Actual emissions rates were estimated from production based emission factors at rated capacity of the plant. This provided a conservative overestimate of actual emissions in most cases. Allowable emission rates from potlines and anode bake furnaces were generally estimated at 1.5 tim es actual emissions which recognizes that annual average emissions must be maintained below the associated emission limit s to ensure that actual emissions to not exceed the emission limit at any time . VII . Emission Process Groups Emissions within the primary aluminum MACT source category were assigned to one of 5 distinct types of emission process groups. No emissions from different sources were combined for discharge t hrough a common stack or vent. Emissions were assigned to the following process groups : Emi ssion Process Group Source Classification Code Emission Type Potroom (control device) outlet 30300199 Stack Potroom (roof monitor) vent 30300107 Area Anode bake furnace 30300105 Stack Paste plant 30300199 Stack Pitch storage tank 30300104 Stack References 1 . Emissions Measurement Test Report - Northwest Aluminum Company. Prepared by Entropy, Inc. June 1994. 77 p. 2 . Kaiser Aluminum and Chemical Corporation Method 5/POM and 13B Testing - Tacoma, Washington - March 1 - 8, 1994. Prepared by AmTes t Air Quality, Inc. July 29, 1994. pp. 1 through 47. [Also draft test data for October 1994.] 3 . Noranda Aluminum Inc. Method 5/POM and 13B Testing - New Madrid, Missouri - September 14 - 20, 1994. Prepared by AmTest Air Quality, Inc. January 10, 1994. pp. 1 through 62. 4 . Kaiser Aluminum and Chemical Corporation Method 5/POM and 13B Testing - Mead, Washington - March 15 - 24, 1994. Prepared by AmTest Air Quality, Inc. November 9, 1994. pp. 1 through 99. 5. U.S. Environmental Protection Agency. Locating and Estimating Air Emissions from Sources of Polycyclic Organic Matter. EPA - 454/R - 98 - 014. Office of Air Quality Planning and Standards, Research Triangle Park, NC. 1998.

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Note: Where: E i,a 

### = Actual prebake potline emissions of compound “i” (ton/year) ;

EF i 

### = Emission factor of compound “i” (lb/ton Al) ; and C = Plant aluminum production capacity (ton Al/year)

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Note: Where: E i,a 

### = Actual Soderberg potline emissions of compound “i” (ton/year) ;

EF i 

### = Emission factor of compound “i” (lb/ton Al) ; and C = Plant aluminum production capacity (ton Al/year)

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Table 5 : Allowable HF emissions

Facility Name Potline TF Limits (lb/ton) Allowable HF Emissions

Potline (t on/year ) Bake Furnace

(t on/year ) Total

(t on/year ) Rio Tinto Alcan 1.9 136.55 8.19 144.74 Alcoa

– Warrick Operations 1.9 215.27 12.92 228.19 Reynolds Metal Company (aka Alcoa

– Massena East) 2.7 101.36 0.00 101.36 Alcoa

– Massena Operations 1.9 87.08 5.23 92.31 Alumax of South Carolina (aka Alcoa

– Mt. Holly) 1.02 87.09 9.73 96.82 Alcoa

– South Plant 1.9 149.78 8.99 158.77 Alcoa

– Rockdale Operations 3.0 293.70 11.16 304.86 Intalco Aluminum 1.6 163.09 11.62 174.71 Alcoa

– Wenatchee Works 1.9 128.19 7.69 135.88 Century Aluminum of KY 2.5 223.67 10.20 233.87 Century Aluminum of WV 3.0 187.00 7.11 194.11 Columbia Falls Aluminum 2.7 212.85 0.00 212.85 Noranda Aluminum 1.9 174.17 10.45 184.62 Ormet Primary Aluminum 3.0 291.5 0 11.08 302.58 Lake Charles Carbon (Alcoa anode plant) Not applicable 0.00 10.00 10.00 Notes: TF = Total fluoride (i.e., hydrogen fluoride + particulate fluoride); HF = Hydrogen fluoride N/A = Not available (no data was provided via the ICR response) The Alumax of South Carolina potline TF limit is a state limit (i.e., not a MACT limit) The Columbia Falls and Reynolds Metal facilities are Soderberg facilities and do not have bake furnaces. The Lake Charles Carbon facility is a n anode production plant and does not have any potlines. Where: E a,p 

### = Allowable HF potline emissions (ton/year);

EL p 

### = Potline emission limit (lb TF/ton Al); and C = Plant aluminum production capacity (ton /year) Where: E a,bf 

### = Allowable HF bake furnace emissions (ton/year);

EL bf 

### = Bake furna ce emission limit (lb TF/ ton anode ); and C = Plant aluminum production capacity (ton/year)

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Table 6: Actual HF emissions from ICRs Facility Name Potline TF Limits (lb/ton) Actual HF Emissions

Stack (ton/year) Vent

(ton/year) Bake Furnace

(ton/year) Alcoa

– Warrick Operations 1.9 7.5 17.6 N/A Alcoa

– Massena Operations 1.9 N/A 6.1 N/A Alumax of South Carolina (aka Alcoa

– Mt. Holly) 1.02 N/A 74.1 N/A Alcoa

– South Plant 1.9 107 169 N/A Alcoa

– Rockdale Operations 3.0 N/A 220.7 8.3 Intalco Aluminum 1.6 N/A 27.2 N/A Columbia Falls Aluminum 2.7 N/A 77.2 0.0 Noranda Aluminum 1.9 3.7 89.3 N/A Ormet Primary Aluminum 3.0 8.7 238.0 N/A Notes: TF = Total fluoride 

### (i.e., hydrogen fluoride + particulate fluoride) HF = Hydrogen fluoride N/A = Not available (no data was provided via the ICR response) The Alumax of South Carolina potline TF limit is a state limit (i.e., not a MACT limit) The Columbia Falls Aluminum facility is a Soderberg facility and does not have a bake furnace

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Table 7: Carbonyl sulfide actual emissions Facility Name Production Capacity (tons Al/year) Reported COS

Emissions (tons/year) Estimated COS

Emissions 1 

### (tons/year) Reported COS

Emissions (lb/ton Al) Rio Tinto Alcan 216,100 308 Alcoa

– Warrick Operations 340,600 485 Reynolds Metal Company (aka Alcoa

– Massena East) 137,800 285 4.14 Alcoa

– Massena Operations 143,300 140 1.96 Alumax of South Carolina (aka Alcoa

– Mt. Holly) 246,900 522 4.23 Alcoa

– South Plant 237,000 396 3.34 Alcoa

– Rockdale Operations 294,300 281 1.91 Intalco Aluminum 306,400 437 Alcoa

– Wenatchee Works 202,800 298 2.94 Century Aluminum of KY 269,000 383 Century Aluminum of WV 187,400 267 Columbia Falls Aluminum 185,200 264 Noranda Aluminum 325,000 463 Ormet Primary Aluminum 292,100 210 1.44 Lake Charles Carbon (Alcoa anode plant) 0 Total 3,383,900 Average 2.85 1 

### Estimated COS emissions based on average emission factor, as follows:

Where: E COS 

### = Potline COS emissions (ton/year); and C = Plant aluminum production capacity (ton/year)

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Table 8 : Estimated actual POM emissions from anode bake furnaces 1 Facility Name Rio Tinto Alcan Alcoa – Warrick Operations Alcoa – Massena Operations Alumax of South Carolina

Alcoa – South Plant Alcoa – Rockdale Operations Intalco Aluminum Alcoa – Wenatchee Works Century Al of K entucky

Century Al of W est V irginia

Noranda Aluminum

Ormet Primary Aluminum

Lake Charles Carbon Bake furnace capacity (tons/year) 123,149 194,148 160,219 140,742 135,087 167,759 174,670 115,609 153,308 106,813 185,300 166,502 150,000 Compound EF i Estimated actual emissions at capacity (E i,bf ) (lb/year) 2 - Chloronaphthalene 1.70E - 06 1.05E - 04 1.65E - 04 1.36E - 04 1.20E - 04 1.15E - 04 1.43E - 04 1.48E - 04 9.83E - 05 1.30E - 04 9.08E - 05 1.58E - 04 1.42E - 04 1.28E - 04 2 - Methylnaphthalene 5.95E - 06 3.66E - 04 5.78E - 04 4.77E - 04 4.19E - 04 4.02E - 04 4.99E - 04 5.20E - 04 3.44E - 04 4.56E - 04 3.18E - 04 5.51E - 04 4.95E - 04 4.46E - 04 Acenaph thene 3.45E - 06 2.12E - 04 3.35E - 04 2.76E - 04 2.43E - 04 2.33E - 04 2.89E - 04 3.01E - 04 1.99E - 04 2.64E - 04 1.84E - 04 3.20E - 04 2.87E - 04 2.59E - 04 Acenaphthylene 5.95E - 06 3.66E - 04 5.78E - 04 4.77E - 04 4.19E - 04 4.02E - 04 4.99E - 04 5.20E - 04 3.44E - 04 4.56E - 04 3.18E - 04 5.51E - 04 4.95E - 04 4.46E - 04 Anthracene 2.98E - 05 1.83E - 03 2.89E - 03 2.38E - 03 2.09E - 03 2.01E - 03 2.50E - 03 2.60E - 03 1.72E - 03 2.28E - 03 1.59E - 03 2.76E - 03 2.48E - 03 2.23E - 03 Benz[a] Anthracene 5.75E - 05 3.54E - 03 5.58E - 03 4.61E - 03 4.05E - 03 3.88E - 03 4.82E - 03 5.02E - 03 3.32E - 03 4.41E - 03 3.07E - 03 5.33E - 03 4.79E - 03 4.31E - 03 Benzo[a ]Pyrene 5.80E - 05 3.57E - 03 5.63E - 03 4.65E - 03 4.08E - 03 3.92E - 03 4.87E - 03 5.07E - 03 3.35E - 03 4.45E - 03 3.10E - 03 5.37E - 03 4.83E - 03 4.35E - 03 Benzo[b]Fluoranthene 5.42E - 04 3.34E - 02 5.26E - 02 4.34E - 02 3.81E - 02 3.66E - 02 4.55E - 02 4.73E - 02 3.13E - 02 4.15E - 02 2.89E - 02 5.02E - 02 4.51E - 02 4.07E - 02 Benzo[g,h,i,]Perylene 5.10E - 04 3.14E - 02 4.95E - 02 4.09E - 02 3.59E - 02 3.44E - 02 4.28E - 02 4.45E - 02 2.95E - 02 3.91E - 02 2.72E - 02 4.73E - 02 4.25E - 02 3.83E - 02 Benzo[k ]Fluoranthene 1.12E - 04 6.90E - 03 1.09E - 02 8.97E - 03 7.88E - 03 7.56E - 03 9.39E - 03 9.78E - 03 6.47E - 03 8.59E - 03 5.98E - 03 1.04E - 02 9.32E - 03 8.40E - 03 Carbazole 2.20E - 05 1.35E - 03 2.14E - 03 1.76E - 03 1.55E - 03 1.49E - 03 1.85E - 03 1.92E - 03 1.27E - 03 1.69E - 03 1.17E - 03 2.04E - 03 1.83E - 03 1.65E - 03 Chrysene 5.60E - 04 3.45E - 02 5.44E - 02 4.49E - 02 3.94E - 02 3.78E - 02 4.70E - 02 4.89E - 02 3.24E - 02 4.29E - 02 2.99E - 02 5.19E - 02 4.66E - 02 4.20E - 02 Dibenzo [a,h]Anthracene 5.36E - 05 3.30E - 03 5.20E - 03 4.29E - 03 3.77E - 03 3.62E - 03 4.50E - 03 4.68E - 03 3.10E - 03 4.11E - 03 2.86E - 03 4.97E - 03 4.46E - 03 4.02E - 03 Fluoranthene 3.75E - 03 2.31E - 01 3.64E - 01 3.00E - 01 2.64E - 01 2.53E - 01 3.15E - 01 3.28E - 01 2.17E - 01 2.87E - 01 2.00E - 01 3.47E - 01 3.12E - 01 2.81E - 01 Fluorene 5.44E - 04 3.35E - 02 5.28E - 02 4.36E - 02 3.83E - 02 3.67E - 02 4.56E - 02 4.75E - 02 3.14E - 02 4.17E - 02 2.91E - 02 5.04E - 02 4.53E - 02 4.08E - 02 Indeno[ 1,2,3 - c,d]Pyrene 2.12E - 04 1.31E - 02 2.06E - 02 1.70E - 02 1.49E - 02 1.43E - 02 1.78E - 02 1.85E - 02 1.23E - 02 1.63E - 02 1.13E - 02 1.96E - 02 1.76E - 02 1.59E - 02 Naphtha lene 1.39E - 05 8.56E - 04 1.35E - 03 1.11E - 03 9.78E - 04 9.39E - 04 1.17E - 03 1.21E - 03 8.03E - 04 1.07E - 03 7.42E - 04 1.29E - 03 1.16E - 03 1.04E - 03 Phenanthrene 1.49E - 02 9.17E - 01 1.45E+ 00 1.19E+ 00 1.05E+ 00 1.01E+ 00 1.25E+ 00 1.30E+ 00 8.61E - 01 1.14E+ 00 7.96E - 01 1.38E+ 00 1.24E+ 00 1.12E+ 00 Pyrene 6.80E - 04 4.19E - 02 6.60E - 02 5.45E - 02 4.79E - 02 4.59E - 02 5.70E - 02 5.94E - 02 3.93E - 02 5.21E - 02 3.63E - 02 6.30E - 02 5.66E - 02 5.10E - 02 Retene 1.90E - 06 1.17E - 04 1.84E - 04 1.52E - 04 1.34E - 04 1.28E - 04 1.59E - 04 1.66E - 04 1.10E - 04 1.46E - 04 1.01E - 04 1.76E - 04 1.58E - 04 1.43E - 04 1 

### These data were converted to tons per year for modeling

Where: E i , bf 

### = Actual bake furnace emission of compound “i” (lb/year);

E F i 

### = Emission factor for compound “i” from testing at prebake plants (lb/ ton green anode ); and C = Bake furnace capacity (ton green anode /year)

### 12

Table 9 . Estimated actual emissions from paste production plants Facility Name Rio Tinto Alcan Alcoa – Warrick Operations Alcoa – Massena Operations Alumax of South Carolina Alcoa – South Plant Alcoa – Rockdale Operations Intalco Aluminum Alcoa – Wenatchee Works Century Al of K entucky Century Al of W est V irginia Columbia Falls Al. Noranda Aluminum Ormet Primary Aluminum Lake Charles Carbon Paste Plant Capacity (tons/y ea r) 122,892 193,743 162,473 146,006 134,805 167,409 174,306 115,368 152,988 106, 590 184,781 156,750 166,155 150,000 Compound EF i Estimated actual emissions at capacity (E i, pp ) ( ton /year) Acenapthene 1.02E - 03 6.27E - 02 9.88E - 02 8.29E - 02 7.45E - 02 6.88E - 02 8.54E - 02 8.89E - 02 5.88E - 02 7.80E - 02 5.44E - 02 9.42E - 02 7.99E - 02 8.47E - 02 7.65E - 02 Acenaphthylene 1.02E - 05 6.27E - 04 9.88E - 04 8.29E - 04 7.45E - 04 6.88E - 04 8.54E - 04 8.89E - 04 5.88E - 04 7.80E - 04 5.44E - 04 9.42E - 04 7.99E - 04 8.47E - 04 7.65E - 04 Anthracene 2.55E - 04 1.57E - 02 2.47E - 02 2.07E - 02 1.86E - 02 1.72E - 02 2.13E - 02 2.22E - 02 1.47E - 02 1.95E - 02 1.36E - 02 2.36E - 02 2.00E - 02 2.12E - 02 1.91E - 02 Benzo(a)anthracene 1.55E - 05 9.52E - 04 1.50E - 03 1.26E - 03 1.13E - 03 1.04E - 03 1.30E - 03 1.35E - 03 8.94E - 04 1.19E - 03 8.26E - 04 1.43E - 03 1.21E - 03 1.29E - 03 1.16E - 03 Benzo(a)pyrene 8.10E - 07 4.98E - 05 7.85E - 05 6.58E - 05 5.91E - 05 5.46E - 05 6.78E - 05 7.06E - 05 4.67E - 05 6.20E - 05 4.32E - 05 7.48E - 05 6.35E - 05 6.73E - 05 6.08E - 05 Benzo(b)fluoranthene 1.47E - 06 9.03E - 05 1.42E - 04 1.19E - 04 1.07E - 04 9.91E - 05 1.23E - 04 1.28E - 04 8.48E - 05 1.12E - 04 7.83E - 05 1.36E - 04 1.15E - 04 1.22E - 04 1.10E - 04 Benzo(g,h, i)perylene 2.48E - 07 1.52E - 05 2.40E - 05 2.01E - 05 1.81E - 05 1.67E - 05 2.08E - 05 2.16E - 05 1.43E - 05 1.90E - 05 1.32E - 05 2.29E - 05 1.94E - 05 2.06E - 05 1.86E - 05 Benzo(k)fluoranthene 7.95E - 07 4.88E - 05 7.70E - 05 6.46E - 05 5.80E - 05 5.36E - 05 6.65E - 05 6.93E - 05 4.59E - 05 6.08E - 05 4.24E - 05 7.35E - 05 6.23E - 05 6.60E - 05 5.96E - 05 Carbazole 1.00E - 04 6.14E - 03 9.69E - 03 8.12E - 03 7.30E - 03 6.74E - 03 8.37E - 03 8.72E - 03 5.77E - 03 7.65E - 03 5.33E - 03 9.24E - 03 7.84E - 03 8.31E - 03 7.50E - 03 Chrysene 1.08E - 05 6.64E - 04 1.05E - 03 8.77E - 04 7.88E - 04 7.28E - 04 9.04E - 04 9.41E - 04 6.23E - 04 8.26E - 04 5.76E - 04 9.98E - 04 8.46E - 04 8.97E - 04 8.10E - 04 Dibenz(a,h)anthracene 3.53E - 07 2.17E - 05 3.42E - 05 2.87E - 05 2.58E - 05 2.38E - 05 2.95E - 05 3.08E - 05 2.04E - 05 2.70E - 05 1.88E - 05 3.26E - 05 2.77E - 05 2.93E - 05 2.65E - 05 Fluoranthene 5.26E - 04 3.23E - 02 5.10E - 02 4.27E - 02 3.84E - 02 3.55E - 02 4.40E - 02 4.58E - 02 3.03E - 02 4.02E - 02 2.80E - 02 4.86E - 02 4.12E - 02 4.37E - 02 3.95E - 02 Fluorene 1.01E - 03 6.21E - 02 9.78E - 02 8.20E - 02 7.37E - 02 6.81E - 02 8.45E - 02 8.80E - 02 5.83E - 02 7.73E - 02 5.38E - 02 9.33E - 02 7.92E - 02 8.39E - 02 7.58E - 02 Indeno(1,2,3,cd)pyrene 2.78E - 07 1.71E - 05 2.69E - 05 2.26E - 05 2.03E - 05 1.87E - 05 2.33E - 05 2.42E - 05 1.60E - 05 2.13E - 05 1.48E - 05 2.57E - 05 2.18E - 05 2.31E - 05 2.09E - 05 2 - methylnaphthalene 5.95E - 06 3.66E - 04 5.76E - 04 4.83E - 04 4.34E - 04 4.01E - 04 4.98E - 04 5.19E - 04 3.43E - 04 4.55E - 04 3.17E - 04 5.50E - 04 4.66E - 04 4.94E - 04 4.46E - 04 Naphthalene 4.45E - 06 2.73E - 04 4.31E - 04 3.62E - 04 3.25E - 04 3.00E - 04 3.72E - 04 3.88E - 04 2.57E - 04 3.40E - 04 2.37E - 04 4.11E - 04 3.49E - 04 3.70E - 04 3.34E - 04 Phenanthrene 1.56E - 03 9.59E - 02 1.51E - 01 1.27E - 01 1.14E - 01 1.05E - 01 1.31E - 01 1.36E - 01 9.00E - 02 1.19E - 01 8.31E - 02 1.44E - 01 1.22E - 01 1.30E - 01 1.17E - 01 Pyrene 2.16E - 04 1.33E - 02 2.09E - 02 1.75E - 02 1.58E - 02 1.46E - 02 1.81E - 02 1.88E - 02 1.25E - 02 1.65E - 02 1.15E - 02 2.00E - 02 1.69E - 02 1.79E - 02 1.62E - 02 Total 0.29 0.46 0.38 0.35 0.32 0.40 0.41 0.27 0.36 0.25 0.44 0.37 0.39 0.36 

### Where: E i,pp 

### = Actual paste production plant emission of compound “i” ( ton /year );

EF i 

### = Emission factor for compound “i” [ from Table 4.4.1 - 3 of EPA - 454/R - 98 - 014 ] (lb/ton paste); and C = Paste production plant capacity (ton paste/year)

### 13

Table 10: Pitch consumption and estimated HAP emissions from pitch storage tanks Facility Name Aluminum Capacity (ton/y ea r) Pas te Plant

Capacity (ton/y ea r) Pitch consumption HC emissions ( ft 3 /y ea r ) HAP

species emissions ( ft 3 /y ea r ) HAP

species emissions ( lb/y ea r ) (ton/year) ( ft/y ea r ) Rio Tinto Alcan 216,100 123,177 27,099 694,845 2,362 827 372 Alcoa

– Warrick Operations 340,600 194,142 42,711 1,095,160 3,724 1,303 586 Alcoa

– Massena Operations 143,300 160,227 35,250 903,845 3,073 1,076 483 Alumax of South Carolina (aka Alcoa

– Mt. Holly) 246,900 140,733 30,961 793,878 2,699 945 425 Alcoa

– South Plant 237,000 135,090 29,720 762,046 2,591 907 408 Alcoa

– Rockdale Operations 294,300 167,751 36,905 946,288 3,217 1,126 506 Intalco Aluminum 306,400 174,648 38,423 985,194 3,350 1,172 527 Alcoa

– Wenatchee Works 202,800 115,596 25,431 652,080 2,217 776 349 Century Aluminum of KY 269,000 153,33 0 33,733 864,938 2,941 1,029 463 Century Aluminum of WV 187,400 106,818 23,500 602,563 2,049 717 322 Columbia Falls Aluminum 185,200 184,781 40,652 1,042,354 3,544 1,240 557 Noranda Aluminum 325,000 185,250 40,755 1,045,000 3,553 1,244 559 Ormet Primary Aluminum 292,100 166,497 36,629 939,214 3,193 1,118 502 Lake Charles Carbon (Alcoa anode plant) See note 150,000 33,000 846,154 2,877 1,007 453 Total 3,383,900 2,158,040 474,769 12,173,559 41,390 14,487 6,511 The Lake Charles Carbon facility is a prebake anode production facility which does not produce aluminum.

Compound specific estimated organic HAP emissions, shown in Table 1 1 are based on applying the speciation profile from the Kaiser - Tacoma Soderberg potline primary control system inlet composition to the calculated total HAP emissions, and converting to ton s per year for modeling.

### 14

Table 11: Actual pitch storage tank emission estimates (tons per year) Facility Name Rio Tinto Alcan

Alcoa – Warrick Operations

Alcoa – Massena Operations

Alumax of South Carolina

Alcoa – South Plant

Alcoa – Rockdale Operations

Intalco Aluminum

Alcoa – Wenatchee Works

Century Al of K entucky

Century Al of W est V irginia

Columbia Falls Al.

Noranda Aluminum

Ormet Primary Aluminum Lake Charles Carbon HAP species 1.86E - 01 2.93E - 01 2.42E - 01 2.12E - 01 2.04E - 01 2.53E - 01 2.63E - 01 1.74E - 01 2.31E - 01 1.61E - 01 2.79E - 01 2.79E - 01 2.51E - 01 2.26E - 01 Acenapthene 6.39E - 04 1.01E - 03 8.31E - 04 7.30E - 04 7.01E - 04 8.70E - 04 9.06E - 04 5.99E - 04 7.95E - 04 5.54E - 04 9.58E - 04 9.61E - 04 8.63E - 04 7.78E - 04 Acenaphthylene 1.16E - 04 1.83E - 04 1.51E - 04 1.33E - 04 1.27E - 04 1.58E - 04 1.65E - 04 1.09E - 04 1.45E - 04 1.01E - 04 1.74E - 04 1.75E - 04 1.57E - 04 1.41E - 04 Anthracene 4.94E - 03 7.78E - 03 6.42E - 03 5.64E - 03 5.41E - 03 6.72E - 03 7.00E - 03 4.63E - 03 6.14E - 03 4.28E - 03 7.40E - 03 7.42E - 03 6.67E - 03 6.01E - 03 Benzo(a) anthracene 9.00E - 03 1.42E - 02 1.17E - 02 1.03E - 02 9.87E - 03 1.23E - 02 1.28E - 02 8.45E - 03 1.12E - 02 7.80E - 03 1.35E - 02 1.35E - 02 1.22E - 02 1.10E - 02 Benzo(a)pyrene 4.06E - 03 6.41E - 03 5.29E - 03 4.64E - 03 4.46E - 03 5.54E - 03 5.76E - 03 3.81E - 03 5.06E - 03 3.52E - 03 6.10E - 03 6.11E - 03 5.49E - 03 4.95E - 03 Benzo(b) fluoranthene 1.10E - 02 1.74E - 02 1.44E - 02 1.26E - 02 1.21E - 02 1.50E - 02 1.56E - 02 1.04E - 02 1.37E - 02 9.57E - 03 1.66E - 02 1.66E - 02 1.49E - 02 1.34E - 02 Benzo(g,h, i) perylene 1.05E - 02 1.65E - 02 1.36E - 02 1.19E - 02 1.15E - 02 1.42E - 02 1.48E - 02 9.81E - 03 1.30E - 02 9.06E - 03 1.57E - 02 1.57E - 02 1.41E - 02 1.27E - 02 Benzo(k) fluoranthene 3.48E - 03 5.49E - 03 4.53E - 03 3.98E - 03 3.82E - 03 4.74E - 03 4.94E - 03 3.27E - 03 4.34E - 03 3.02E - 03 5.23E - 03 5.24E - 03 4.71E - 03 4.24E - 03 Carbazole 2.26E - 03 3.57E - 03 2.95E - 03 2.59E - 03 2.48E - 03 3.08E - 03 3.21E - 03 2.13E - 03 2.82E - 03 1.96E - 03 3.40E - 03 3.41E - 03 3.06E - 03 2.76E - 03 2 - chloro naphthalene 5.81E - 06 9.15E - 06 7.55E - 06 6.63E - 06 6.37E - 06 7.91E - 06 8.23E - 06 5.45E - 06 7.23E - 06 5.04E - 06 8.71E - 06 8.73E - 06 7.85E - 06 7.07E - 06 Chrysene 1.60E - 02 2.52E - 02 2.08E - 02 1.82E - 02 1.75E - 02 2.17E - 02 2.26E - 02 1.50E - 02 1.99E - 02 1.38E - 02 2.40E - 02 2.40E - 02 2.16E - 02 1.94E - 02 Dibenzo(a,h) anthracene 6.97E - 04 1.10E - 03 9.06E - 04 7.96E - 04 7.64E - 04 9.49E - 04 9.88E - 04 6.54E - 04 8.67E - 04 6.04E - 04 1.05E - 03 1.05E - 03 9.42E - 04 8.49E - 04 Fluoranthene 4.06E - 02 6.41E - 02 5.29E - 02 4.64E - 02 4.46E - 02 5.54E - 02 5.76E - 02 3.81E - 02 5.06E - 02 3.52E - 02 6.10E - 02 6.11E - 02 5.49E - 02 4.95E - 02 Fluorene 2.41E - 03 3.80E - 03 3.13E - 03 2.75E - 03 2.64E - 03 3.28E - 03 3.42E - 03 2.26E - 03 3.00E - 03 2.09E - 03 3.61E - 03 3.62E - 03 3.26E - 03 2.93E - 03 Indeno(1,2,3,cd) pyrene 1.95E - 03 3.07E - 03 2.53E - 03 2.22E - 03 2.13E - 03 2.65E - 03 2.76E - 03 1.83E - 03 2.42E - 03 1.69E - 03 2.92E - 03 2.93E - 03 2.63E - 03 2.37E - 03 2 - methyl naphthalene 2.03E - 04 3.20E - 04 2.64E - 04 2.32E - 04 2.23E - 04 2.77E - 04 2.88E - 04 1.91E - 04 2.53E - 04 1.76E - 04 3.05E - 04 3.06E - 04 2.75E - 04 2.47E - 04 Naphthalene 5.81E - 05 9.15E - 05 7.55E - 05 6.63E - 05 6.37E - 05 7.91E - 05 8.23E - 05 5.45E - 05 7.23E - 05 5.04E - 05 8.71E - 05 8.73E - 05 7.85E - 05 7.07E - 05 Phenanthrene 4.35E - 02 6.86E - 02 5.66E - 02 4.98E - 02 4.78E - 02 5.93E - 02 6.17E - 02 4.09E - 02 5.42E - 02 3.78E - 02 6.53E - 02 6.55E - 02 5.89E - 02 5.30E - 02 Pyrene 3.48E - 02 5.49E - 02 4.53E - 02 3.98E - 02 3.82E - 02 4.74E - 02 4.94E - 02 3.27E - 02 4.34E - 02 3.02E - 02 5.23E - 02 5.24E - 02 4.71E - 02 4.24E - 02 Retene 5.81E - 06 9.15E - 06 7.55E - 06 6.63E - 06 6.37E - 06 7.91E - 06 8.23E - 06 5.45E - 06 7.23E - 06 5.04E - 06 8.71E - 06 8.73E - 06 7.85E - 06 7.07E - 06