**MEMORANDUM**

DATE: September 10, 2015 SUBJECT: Redline Version of Subpart LL showing the Differences from the Current Subpart LL and the 2015 Amended Rule TO **:** David Putney, U.S. Environmental Protection Agency From: David Green and Matt Hakos, RTI International

The purpose of this memorandum is to present a redline version of subpart LL, Primary Aluminum Production Source Category NESHAP, that shows the changes that have been made in the current rule by the 2015 final amendments.1 **Subpart LL—National Emission Standards for Hazardous Air Pollutants for Primary Aluminum Reduction Plants** 
**§ 63.840 Applicability.** (a) Except as provided in paragraph (b) of this section, the requirements of this subpart apply to the owner or operator of each new or existing pitch storage tank and new or existing potline, paste production plant, or anode bake furnace associated with primary aluminum production and located at a major source as defined in §63.2. (b) The requirements of this subpart do not apply to any existing anode bake furnace that is not located on the same site as a primary aluminum reduction plant. The owner or operator shall comply with the State MACT determination established by the applicable regulatory authority. (c) An owner or operator of an affected facility (potroom group or anode bake furnace) under §60.190 of this chapter may elect to comply with either the requirements of §63.845 of this subpart or the requirements of subpart S of part 60 of this chapter. **§ 63.841 Incorporation by reference. Removed and Reserved.**  (a) The following material is incorporated by reference in the corresponding sections noted. This incorporation by reference was approved by the Director of the Federal Register2 on October 7, 1997, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date of approval, and notice of any change in the materials will be published in theFederal Register.Revisions to “Industrial Ventilation: A Manual of Recommended Practice” (22nd ed.) are applicable only after publication of a document in the Federal Register to amend subpart LL to require use of the new information. (1) Chapter 3, “Local Exhaust Hoods” and Chapter 5, “Exhaust System Design Procedure” of “Industrial Ventilation: A Manual of Recommended Practice,” American Conference of Governmental Industrial Hygienists, 22nd edition, 1995, IBR approved for §§63.843(b) and 63.844(b); and (2) ASTM D 2986–95A, Standard Practice for Evaluation of Air Assay Media by the Monodisperse DOP (Dioctyl Phthalate) Smoke Test, IBR approved for section 7.1.1 of Method 315 in appendix A to this part. (b) The materials incorporated by reference are available for at the National Archives and Records Administration (NARA), and at the Air and Radiation Docket Center, U.S. EPA, 1200 Pennsylvania Ave., NW., Washington, DC. For information on the availability of this material at NARA, call 202–741–6030, or go
to: http://www.archives.gov/federal_register/code_of_federal_regulat3 ions/ibr_locations.html. The materials also are available for purchase from one of the following addresses: (1) Customer Service Department, American Conference of Governmental Industrial Hygienists (ACGIH), 1330 Kemper Meadow Drive, Cincinnati, Ohio 45240, telephone number (513) 742–2020;

or (2) American Society for Testing and Materials, 100 Bar Harbour Drive, West Conshohocken, Pennsylvania 19428, telephone number (610) 832–9500. **§ 63.842 Definitions.** Terms used in this subpart are defined in the Clean Air Act as amended (the Act), in §63.2, or in this section as follows: Anode bake cycle means the period during which the regularly repeated sequence of loading, preheating, firing, cooling, and removing anodes from all sections within an anode bake furnace occurs one time. Anode bake furnace means an oven in which the formed green anodes are baked for use in a prebake process. This definition includes multiple anode bake furnaces controlled by a common control device (bake furnaces controlled by a common control device are considered to be one source). Center-worked prebake (CWPB) process means a method of primary aluminum reduction using the prebake process in which the alumina feed is added down the center of the reduction cell.4 Center-worked prebake one (CWPB1) means all existing center-worked prebake potlines not defined as center-worked prebake two (CWPB2) or center-worked prebake three (CWPB3) potlines. Center-worked prebake two (CWPB2) means all existing center-worked prebake potlines located at Alcoa in Rockdale, Texas; Kaiser Aluminum in Mead, Washington; Ormet Corporation in Hannibal, Ohio; Ravenswood Aluminum in Ravenswood, West Virginia; Reynolds Metals in Troutdale, Oregon; and Vanalco Aluminum in Vancouver, Washington. Center-worked prebake three (CWPB3) means all existing center-worked prebake potlines that produce very high purity aluminum, have a wet scrubber for the primary control system, and are located at the NSA primary aluminum plant in Hawesville, Kentucky. Continuous parameter monitoring system means the total equipment that may be required to meet the data acquisition and availability requirements of this subpart, used to sample, condition (if applicable), analyze, and provide a record of process or control system parameters. Horizontal stud Soderberg (HSS) process means a method of primary aluminum reduction using the Soderberg process in which the electrical current is introduced to the anode by steel rods (studs) inserted into the side of a monolithic anode.5 High purity aluminum means aluminum produced with an average purity level of at least 99.9 percent. Modified potroom group means an existing potroom group to which any physical change in, or change in the method of operation of, results in an increase in the amount of total fluoride emitted into the atmosphere by that potroom group. Operating day means a 24-hour period between 12 midnight and the following midnight during which an affected source operates at any time. It is not necessary for operations to occur for the entire 24-hour period. Particulate matter (PM) means, for the purposes of this subpart, emissions of particulate matter that serve as a measure of total particulate emissions and as a surrogate for metal hazardous air pollutants contained in the particulates, including but not limited to: antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, nickel and selenium. Paste production plant means the processes whereby calcined petroleum coke, coal tar pitch (hard or liquid), and/or other materials are mixed, transferred, and formed into briquettes or paste for vertical stud Soderberg (VSS) and HSS processes or into green anodes for a prebake process. This definition includes all operations from initial mixing to final forming (i.e., briquettes, paste, green anodes) within the paste plant, including conveyors and units managing heated liquid pitch.6 Pitch storage tank means any fixed roof tank that is used to store liquid pitch that is not part of the paste production plant. Polychlorinated biphenyl (PCB) means any or all of the 209 possible chlorinated biphenyl isomers. Polycyclic organic matter (POM) means organic matter extractable by methylene chloride as determined by Method 315 in appendix A to this part or by an approved alternative method. Potline means a single, discrete group of electrolytic reduction cells electrically connected in series, in which alumina is reduced to form aluminum.
Potroom means a building unit that houses a group of electrolytic cells in which aluminum is produced. Potroom group means an uncontrolled potroom, a potroom that is controlled individually, or a group of potrooms or potroom segments ducted to a common control system. Prebake process means a method of primary aluminum reduction that uses an anode that was baked in an anode bake furnace, which is introduced into the top of the reduction cell and consumed as part of the reduction process. Primary aluminum reduction plant means any facility manufacturing aluminum by electrolytic reduction. Primary control system means the equipment used to capture the gases and particulate matter evacuated directly from the7 reduction cell and the emission control device(s) used to remove pollutants prior to discharge of the cleaned gas to the atmosphere. A roof scrubber is not part of the primary control system. Primary emissions means the emissions discharged from the primary control system. Reconstructed potroom group means an existing potroom group for which the components are replaced to such an extent that the fixed capital cost of the new components exceeds 50 percent of the fixed capital cost that would be required to construct a comparable entirely new potroom group, and for which it is technologically and economically feasible to meet the applicable emission limits for total fluoride set forth in this subpart. Reconstruction means the replacement of components of a source to such an extent that: (1) All of the major components of the source are replaced (for example, the major components of a potline include the raw material handling system, reduction cells, superstructure, hooding, ductwork, etc.); and (2) It is technologically and economically feasible for the reconstructed source to meet the standards for new sources established in this subpart.8 Roof monitor means that portion of the roof of a potroom building where gases not captured at the cell exit from the potroom. Secondary emissions means the fugitive emissions that are not captured and controlled by the primary control system and that escape through the roof monitor or through roof scrubbers. Side-worked prebake (SWPB) process means a method of primary aluminum reduction using the prebake process, in which the alumina is added along the sides of the reduction cell. Soderberg process means a method of primary aluminum reduction in which the anode paste mixture is baked in the reduction pot by the heat resulting from the electrolytic
process. Startup of an anode bake furnace means the process ofinitiating heating to the anode bake furnace. The startup or restart of the furnace begins when the heating begins. The startup or re-start concludes at the start of the second anode bake cycle if the furnace was at ambient temperature upon startup or when the anode bake cycle resumes if the furnace was not at ambient temperature. Total fluorides (TF) means elemental fluorine and all fluoride compounds as measured by Methods 13A or 13B in appendix A to part 60 of this chapter or by an approved alternative method.9 Toxicity equivalence (TEQ) means an international method of expressing toxicity equivalents for PCBs as defined in U. S. EPA, Recommended Toxicity Equivalence Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds, EPA/100/R-10/005 December 2010. Vertical stud Soderberg (VSS) process means a method of primary aluminum reduction using the Soderberg process, in which the electrical current is introduced to the anode by steel rods (studs) inserted into the top of a monolithic anode. Vertical stud Soderberg one (VSS1) means all existing vertical stud Soderberg potlines located either at Northwest Aluminum in The Dalles, Oregon, or at Goldendale Aluminum in Goldendale, Washington. Vertical stud Soderberg two (VSS2) means all existing vertical stud Soderberg potlines located at Columbia Falls Aluminum in Columbia Falls, Montana. **§ 63.843 Emission limits for existing sources.** (a) Potlines. The owner or operator shall not discharge or cause to be discharged into the atmosphere any emissions of TF ,

or POM , PM, nickel, arsenic or PCB in excess of the applicable limits in paragraphs (a)(1) and (a)(2) through (a)(6) of this section. (1) TF limits. Emissions of TF shall not exceed:10 (i) 0.95 kg/Mg (1.9 lb/ton) of aluminum produced for each CWPB1 potline; (ii) 1.5 kg/Mg (3.0 lb/ton) of aluminum produced for each CWPB2 potline; (iii) 1.25 kg/Mg (2.5 lb/ton) of aluminum produced for each CWPB3 potline; (iv) 0.8 kg/Mg (1.6 lb/ton) of aluminum produced for each SWPB potline; and (v) 1.1 kg/Mg (2.2 lb/ton) of aluminum produced for each VSS1 potline;[Reserved] (vi) 1.35 kg/Mg (2.7 lb/ton) of aluminum produced for each VSS2 potline .; and (vii) 1.35 kg/Mg (2.7 lb/ton) of aluminum produced for each HSS potline. (2) POM limits. Emissions of POM shall not exceed: (i) 2.35 kg/Mg (4.7 lb/ton) of aluminum produced for each HSS potline;[Reserved] (ii) 1.2 kg/Mg (2.4 lb/ton) of aluminum produced for each VSS1 potline; and[Reserved] (iii) 2.850.85 kg/Mg ( 5.71.9 lb/ton) of aluminum produced for each VSS2 potline ;. (iv) 0.55 kg/Mg (1.1 lb/ton) of aluminum produced for each CWPB1 prebake potline;11 (v) 6.0 kg/Mg (12 lb/ton) of aluminum produced for each CWPB2 prebake potline; (vi) 1.4 kg/Mg (2.7 lb/ton) of aluminum produced for each CWPB3 prebake potline; and (vii) 8.5 kg/Mg (17 lb/ton) of aluminum produced for each SWPB prebake potline. (3) PM limits. Emissions of PM shall not exceed: (i) 3.7 kg/Mg (7.4 lb/ton) of aluminum produced for each CWPB1 potline; (ii) 5.5 kg/Mg (11 lb/ton) of aluminum produced for each CWPB2 potline; (iii) 10 kg/Mg (20 lb/ton) of aluminum produced for each CWPB3 potline; (iv) 2.45 kg/Mg (4.9 lb/ton) of aluminum produced for each SWPB potline; and (v) 13 kg/Mg (26 lb/ton) of aluminum produced for each VSS2 potline. (4) Nickel limit. Emissions of nickel shall not exceed 0.07 lb/ton of aluminum produced from each VSS2 potline at a primary aluminum reduction plant. (5) Arsenic limit. Emissions of arsenic shall not exceed 0.006 lb/ton of aluminum produced from each VSS2 potline at a primary aluminum reduction plant.12 (6) PCB limit. Emissions of PCB shall not exceed 2.0 μg toxicity equivalence (TEQ) per ton of aluminum produced from each VSS2 potline at a primary aluminum reduction plant. ( 37 ) Change in subcategory. Any potline, other than a reconstructed potline, that is changed such that its applicable subcategory also changes shall meet the applicable emission limit in this subpart for the original subcategory or the new subcategory, whichever is more stringent. (b) Paste production plants. The owner or operator shall install, operate, and maintain equipment to capture and control POM and PM emissions from each paste production plant. (1) The emission capture system shall be installed and operated to meet the generally accepted engineering standards for minimum exhaust rates as published by the American Conference of Governmental Industrial Hygienists in Chapters 3 and 5 of “Industrial Ventilation: A Handbook of Recommended Practice” (incorporated by reference ; in §63.841 of this part see § 63.14 ); and (2) Captured emissions shall be routed through a closed system to a dry coke scrubber; or (3) The owner or operator may submit a written request for use of an alternative control device to the applicable regulatory authority for review and approval. The request shall contain information and data demonstrating that the alternative13 control device achieves POM emissions less than 0.011 lb/ton of paste for plants with continuous mixers or POM emissions less than 0.024 lb/ton of paste for plants with batch mixers. The POM emission rate shall be determined by sampling using Method 315 in appendix A to this part. (4) PM limit. Emissions of PM shall not exceed 0.041 kg/Mg (0.082 lb/ton) of paste. (c) Anode bake furnaces. The owner or operator shall not discharge or cause to be discharged into the atmosphere any emissions of TF , or POM , PM or mercury in excess of the limits in paragraphs (c)(1) and (c)( 24 ) of this section. (1) TF limit. Emissions of TF shall not exceed 0.10 kg/Mg (0.20 lb/ton) of green anode; and (2) POM limit. Emissions of POM shall not exceed 0.09 kg/Mg (0.18 lb/ton) of green anode .; (3) PM limit. Emissions of PM shall not exceed 0.10 kg/Mg (0.20 lb/ton) of green anode; and (4) Mercury limit. Emissions of mercury shall not exceed 1.7 μ g/dscm. (d) Pitch storage tanks. Each pitch storage tank shall be equipped with an emission control system designed and operated to reduce inlet emissions of POM by 95 percent or greater.14 (e) COS limit. Emissions of COS must not exceed 1.95 kg/Mg (3.9 lb/ton) of aluminum produced for each potline. (f) At all times, the owner or operator must operate and maintain any affected source, including associated air pollution control equipment and monitoring equipment, in a manner consistent with safety and good air pollution control practices for minimizing emissions. Determination of whether such operation and maintenance procedures are being used will be based on information available to the Administrator which may include, but is not limited to, monitoring results, review of operation and maintenance procedures, review of operation and maintenance records and inspection of the source. **§ 63.844 Emission limits for new or reconstructed sources.** (a) Potlines. The owner or operator shall not discharge or cause to be discharged into the atmosphere any emissions of TF ,

or POM , nickel, arsenic or PCB in excess of the limits in paragraphs (a)(1) and (a)(2)through (a)(6) of this section. (1) TF limit. Emissions of TF shall not exceed 0.6 kg/Mg (1.2 lb/ton) of aluminum produced; and (2) POM limit. Emissions of POM from Soderberg potlines shallmust not exceed 0.320.39 kg/Mg ( 0.630.77 lb/ton) of aluminum produced. (3) PM limit. Emissions of PM from potlines must not exceed 2.45 kg/Mg (4.9 lb/ton) of aluminum produced.15 (4) Nickel limit. Emissions of nickel shall not exceed 0.035 kg/Mg (0.07 lb/ton) of aluminum produced from each Soderberg potline at a primary aluminum reduction plant. (5) Arsenic limit. Emissions of arsenic shall not exceed 0.003 kg/Mg (0.006 lb/ton) of aluminum produced from each Soderberg potline at a primary aluminum reduction plant. (6) PCB limit. Emissions of PCB shall not exceed 2.0 μg TEQ/ton of aluminum produced from each Soderberg potline at a primary aluminum reduction plant. (b) Paste production plants. The owner or operator shall meet the requirements in §63.843(b) for existing paste production plants.(1) The owner or operator shall meet the requirements in § 63.843(b)(1) through (3) for existing paste production plants and shall not discharge or cause to be discharged into the atmosphere any emissions of PM in excess of the limit in paragraph (b)(2) of this section. (2) Emissions of PM shall not exceed 0.0028 kg/Mg (0.0056 lb/ton) of green anode. (c) Anode bake furnaces. The owner or operator shall not discharge or cause to be discharged into the atmosphere any emissions of TF , or POM in excess of the limits in paragraphs (c)(1) and (c)(2) of this sectionPM, POM or mercury in excess of the limits in paragraphs (c)(1) through (4) of this section
.16 (1) TF limit. Emissions of TF shall not exceed 0.01 kg/Mg (0.02 lb/ton) of green anode; and (2) POM limit. Emissions of POM shall not exceed 0.025 kg/Mg (0.05 lb/ton) of green anode .; (3) PM limit. Emissions of PM shall not exceed 0.035 kg/Mg (0.07 lb/ton) of green anode; and (4) Mercury limit. Emissions of mercury shall not exceed 1.7 μ g/dscm. (d) Pitch storage tanks. Each pitch storage tank shall be equipped with an emission control system designed and operated to reduce inlet emissions of POM by 95 percent or greater. (e) COS limit. Emissions of COS must not exceed 1.55 kg/Mg (3.1 lb/ton) of aluminum produced for each potline. (f) At all times, the owner or operator must operate and maintain any affected source, including associated air pollution control equipment and monitoring equipment, in a manner consistent with safety and good air pollution control practices for minimizing emissions. Determination of whether such operation and maintenance procedures are being used will be based on information available to the Administrator which may include, but is not limited to, monitoring results, review of operation and maintenance procedures, review of operation and maintenance records and inspection of the source.17 **§ 63.845 Incorporation of new source performance stadards for potroom groups.**  (a) Applicability. The provisions in paragraphs (a) through (i) of this section shall apply to any Soderberg, CWPB2, and CWPB3 potline that adds a new potroom group to an existing potline or that is associated with a potroom group that meets the definition of “modified potroom group” or “reconstructed potroom group.” (1) The following shall not, by themselves, be considered to result in a potroom group modification: (i) Maintenance, repair, and replacement that the applicable regulatory authority determines to be routine for the potroom group; (ii) An increase in production rate of an existing potroom group, if that increase can be accomplished without a capital expenditure on that potroom group; (iii) An increase in the hours of operation; (iv) Use of an alternative fuel or raw material if, prior to the effective date of this subpart, the existing potroom group was designed to accommodate that alternative use; (v) The addition or use of any system or device whose primary function is the reduction of air pollutants, except when an emission control system is removed or is replaced by a system18 that the applicable regulatory authority determines to be less environmentally beneficial; and (vi) The relocation or change in ownership of an existing potroom group. (2) The provisions in paragraphs (a)(2)(i) through (a)(2)(iv) of this section apply when the applicable regulatory authority must determine if a potroom group meets the definition of reconstructed potroom group. (i) “Fixed capital cost” means the capital needed to provide all the depreciable components. (ii) If an owner or operator of an existing potroom group proposes to replace components, and the fixed capital cost of the new components exceeds 50 percent of the fixed capital cost that would be required to construct a comparable entirely new potroom group, he/she shall notify the applicable regulatory authority of the proposed replacements. The notice must be postmarked 60 days (or as soon as practicable) before construction of the replacements is commenced and must include the following information: (A) Name and address of the owner or operator; (B) The location of the existing potroom group; (C) A brief description of the existing potroom group and the components that are to be replaced;19 (D) A description of the existing air pollution control equipment and the proposed air pollution control equipment; (E) An estimate of the fixed capital cost of the replacements and of constructing a comparable entirely new potroom group; (F) The estimated life of the existing potroom group after the replacements; and (G) A discussion of any economic or technical limitations the potroom group may have in complying with the applicable standards of performance after the proposed replacements. (iii) The applicable regulatory authority will determine, within 30 days of the receipt of the notice required by paragraph (a)(2)(ii) of this section and any additional information he/she may reasonably require, whether the proposed replacement constitutes a reconstructed potroom group. (iv) The applicable regulatory authority's determination under paragraph (a)(2)(iii) of this section shall be based on: (A) The fixed capital cost of the replacements in comparison to the fixed capital cost that would be required to construct a comparable entirely new potroom group; (B) The estimated life of the potroom group after the replacements compared to the life of a comparable entirely new potroom group;20 (C) The extent to which the components being replaced cause or contribute to the emissions from the potroom group; and (D) Any economic or technical limitations on compliance with applicable standards of performance that are inherent in the proposed replacements. (b) Lower TF emission limit. The owner or operator shall calculate a lower TF emission limit for any potline associated with the modified potroom group, reconstructed potroom group, or new potroom group using the following equation:
L 1 =f 1 ×L PG1 +(1

− f 1 )×L PL Where:
L 1 =the lower TF emission limit in kg/Mg (lb/ton); f 1 =the fraction of the potline's total aluminum production capacity that is contained within all modified potroom groups, reconstructed potroom groups, and new potroom groups;
L PG1 =0.95 kg/Mg (1.9 lb/ton) for prebake potlines and 1.0 kg/Mg (2.0 lb/ton) for Soderberg potlines; and
L PL =the TF emission limit from §63.843(a)(1) for the appropriate potline subcategory that would have otherwise applied to the potline. (c) Upper TF emission limit. The owner or operator shall calculate an upper TF emission limit for any potline associated with the modified potroom group, reconstructed potroom group, or new potroom group using the following equation:21 L 2 =f 1 ×L PG2 +(1

− f 1 )×L PL Where:
L 2 =the upper TF emission limit in kg/Mg (lb/ton); and
L PG2 =1.25 kg/Mg (2.5 lb/ton) for prebake potlines and 1.3 kg/Mg (2.6 lb/ton) for Soderberg potlines. (d) Recalculation. The TF emission limits in paragraphs (b) and (c) of this section shall be recalculated each time a new potroom group is added to the potline and each time an additional potroom group meets the definition of “modified potroom group” or “reconstructed potroom group.” (e) Emission limitation. The owner or operator shall not discharge or cause to be discharged into the atmosphere emissions of TF from any potline associated with the modified potroom group, reconstructed potroom group, or new potroom group that exceed the lower emission limit calculated in paragraph (b) of this section, except that emissions less than the upper limit calculated in paragraph (c) of this section will be considered in compliance if the owner or operator demonstrates that exemplary operation and maintenance procedures were used with respect to the emission control system and that proper control equipment was operating at the potline during the performance
test. (f) Report. Within 30 days of any performance test that reveals emissions that fall between the lower limit calculated22 in paragraph (b) of this section and the upper limit calculated in paragraph (c) of this section, the owner or operator shall submit to the applicable regulatory authority a report indicating whether all necessary control devices were online and operating properly during the performance test, describing the operating and maintenance procedures followed, and setting forth any explanation for the excess emissions. (g) Procedures to determine TF emissions. The owner or operator shall determine TF emissions for the potline using the following procedures: (1) Determine the emission rate of TF in kg/Mg (lb/ton) from sampling secondary emissions and the primary control system for all new potroom groups, modified potroom groups, and reconstructed potroom groups using the procedures, equations, and test methods in §§63.847, 63.848, and 63.849. (2) Determine the emission rate of TF in kg/Mg (lb/ton) from sampling secondary emissions and the primary control system for potroom groups or sections of potroom groups within the potline that are not new potroom groups, modified potroom groups, or reconstructed potroom groups according to paragraphs (g)(2)(i) or (g)(2)(ii) of this section. (i) Determine the mass emission rate of TF in kg/Mg (lb/ton) from at least one potroom group within the potline that is not a new potroom group, modified potroom group, or23 reconstructed potroom group using the procedures, equations, and test methods in §§63.847, 63.848, and 63.849, or (ii) Use the results of the testing required by paragraph (g)(1) of this section to represent the entire potline based on a demonstration that the results are representative of the entire potline. Representativeness shall be based on showing that all of the potroom groups associated with the potline are substantially equivalent in terms of their structure, operability, type of emissions, volume of emissions, and concentration of emissions. (3) Calculate the TF emissions for the potline in kg/Mg (lb/ton) based on the production-weighted average of the TF emission rates from paragraphs (g)(1) and (g)(2) of this section using the following equation: E=f 1 ×E PG1 +(1-f 1 )×E PL where: E=the TF emission rate for the entire potline, kg/Mg (lb/ton); f 1 =the fraction of the potline's total aluminum production rate that is contained within all modified potroom groups, reconstructed potroom groups, and new potroom groups;
E PG1 =the TF emission rate from paragraph (g)(1) of this section for all modified potroom groups, reconstructed potroom groups, and new potroom groups, kg/Mg (lb/ton); and24 E PL =the TF emission rate for the balance of the potline from paragraph (g)(2) of this section, kg/Mg (lb/ton). Compliance is demonstrated when TF emissions for the potline meet the requirements in paragraph (e) of this section. (4) As an alternative to sampling as required in paragraphs (g)(1) and (g)(2) of this section, the owner or operator may perform representative sampling of the entire potline subject to the approval of the applicable regulatory authority. Such sampling shall provide coverage by the sampling equipment of both the new, modified, or reconstructed potroom group and the balance of the potline. The coverage for the new, modified, or reconstructed potroom group must meet the criteria specified in the reference methods in §63.849. TF emissions shall be determined for the potline using the procedures, equations, and test methods in §§63.847, 63.848, and 63.849. Compliance is demonstrated when TF emissions for the potline meet the requirements in paragraph (e) of this section. (h) Opacity. Except as provided in paragraph (i) of this section, the owner or operator shall not discharge or cause to be discharged into the atmosphere from the modified potroom group, reconstructed potroom group, or new potroom group any emissions of gases that exhibit 10 percent opacity or greater.25 (i) Alternative opacity limit. An alternative opacity limit may be established in place of the opacity limit in paragraph (h) of this section using the following procedures: (1) If the regulatory authority finds that a potline is in compliance with the applicable TF standard for which performance tests are conducted in accordance with the methods and procedures in §63.849 but during the time such performance tests are being conducted fails to meet any applicable opacity standard, the regulatory authority shall notify and advise the owner or operator that he/she may petition the regulatory authority within 10 days of receipt of notification to make appropriate adjustment to the opacity standard. (2) The regulatory authority will grant such a petition upon a demonstration by the owner or operator that the potroom group and associated air pollution control equipment were operated and maintained in a manner to minimize the opacity of emissions during the performance tests; that the performance tests were performed under the conditions established by the regulatory authority; and that the potroom group and associated air pollution control equipment were incapable of being adjusted or operated to meet the applicable opacity standard. (3) As indicated by the performance and opacity tests, the regulatory authority will establish an opacity standard for any potroom group meeting the requirements in paragraphs (i)(1) and26 (i)(2) of this section such that the opacity standard could be met by the potroom group at all times during which the potline is meeting the TF emission limit. (4) The alternative opacity limit established in paragraph (i)(3) of this section shall not be greater than 20 percent opacity. **§ 63.846 Emission averaging.** (a) General. The owner or operator of an existing potline or anode bake furnace in a State that does not choose to exclude emission averaging in the approved operating permit program may demonstrate compliance by emission averaging according to the procedures in this section. (b) Potlines. The owner or operator may average TF emissions from potlines and demonstrate compliance with the limits in Table 1 of this subpart using the procedures in paragraphs (b)(1) and (b)(2) of this section. The owner or operator also may average POM emissions from potlines and demonstrate compliance with the limits in Table 2 of this subpart using the procedures in paragraphs (b)(1) and (b)(3) of this section.The owner or operator may average emissions from potlines and demonstrate compliance with the limits in Tables 1 through 3 of this subpart using the procedures in paragraphs (b)(1) through (3) of this section.27 (1) Monthly average emissions of TF and/or quarterly average emissions of POM shall not exceed the applicable emission limit in Table 1 of this subpart (for TF emissions) and/or Table 2 of this subpart (for POM emissions). The emission rate shall be calculated based on the total emissions from all potlines over the period divided by the quantity of aluminum produced during the period, from all potlines comprising the averaging group. (2) To determine compliance with the applicable emission limit in Table 1 of this subpart for TF emissions, the owner or operator shall determine the monthly average emissions (in lb/ton) from each potline from at least three runs per potline each month for TF secondary emissions using the procedures and methods in §§63.847 and 63.849. The owner or operator shall combine the results of secondary TF monthly average emissions with the TF results for the primary control system and divide total emissions by total aluminum production. (3) To determine compliance with the applicable emission limit in Table 2 of this subpart for POM emissions, the owner or operator shall determine the quarterly average emissions (in lb/ton) from each potline from at least one run each month for POM emissions using the procedures and methods in §§63.847 and 63.849. The owner or operator shall combine the results of secondary POM quarterly average emissions with the POM results28 for the primary control system and divide total emissions by total aluminum production. (1) Semiannual average emissions of TF shall not exceed the applicable emission limit in Table 1 of this subpart. The emission rate shall be calculated based on the total primary and secondary emissions from all potlines comprising the averaging group over the period divided by the quantity of aluminum produced during the period, from all potlines comprising the averaging group. To determine compliance with the applicable emission limit in Table 1 of this subpart for TF emissions, the owner or operator shall determine the average emissions (in lb/ton) from each potline from at least three runs per potline semiannually for TF secondary emissions and at least three runs per potline primary control system each year using the procedures and methods in §§ 63.847 and 63.849. The owner or operator shall combine the results of secondary TF average emissions with the TF results for the primary control system and divide total emissions by total aluminum production. (2) Semiannual average emissions of POM shall not exceed the applicable emission limit in Table 2 of this subpart. The emission rate shall be calculated based on the total primary and secondary emissions from all potlines comprising the averaging group over the period divided by the quantity of aluminum produced during the period, from all potlines comprising the29 averaging group. To determine compliance with the applicable emission limit in Table 2 of this subpart for POM emissions, the owner or operator shall determine the average emissions (in lb/ton) from each potline from at least three runs per potline semiannually for POM secondary emissions and at least three runs per potline primary control system each year for POM primary emissions using the procedures and methods in §§ 63.847 and 63.849. The owner or operator shall combine the results of secondary POM average emissions with the POM results for the primary control system and divide total emissions by total aluminum production. (3) Semiannual average emissions of PM shall not exceed the applicable emission limit in Table 3 of this subpart. The emission rate shall be calculated based on the total primary and secondary emissions from all potlines comprising the potline group over the period divided by the quantity of aluminum produced during the period, from all potlines comprising the averaging group. To determine compliance with the applicable emission limit in Table 3 of this subpart for PM emissions, the owner or operator shall determine the average emissions (in lb/ton) from each potline from at least three runs per potline semiannually for PM secondary emissions and at least three runs per potline primary control system each year for PM primary emissions using the procedures and methods in §§ 63.847 and30 63.849. The owner or operator shall combine the results of secondary PM average emissions with the PM results for the primary control system and divide total emissions by total aluminum production. (c) Anode bake furnaces. The owner or operator may average TF emissions from anode bake furnaces and demonstrate compliance with the limits in Table 3 of this subpart using the procedures in paragraphs (c)(1) and (c)(2) of this section. The owner or operator also may average POM emissions from anode bake furnaces and demonstrate compliance with the limits in Table 3 of this subpart using the procedures in paragraphs (c)(1) and (c)(2) of this section.The owner or operator may average TF emissions from anode bake furnaces and demonstrate compliance with the limits in Table 4 of this subpart using the procedures in paragraphs (c)(1) and (2) of this section. The owner or operator also may average POM emissions from anode bake furnaces and demonstrate compliance with the limits in Table 4 of this subpart using the procedures in paragraphs (c)(1) and (2) of this section. The owner or operator also may average PM emissions from anode bake furnaces and demonstrate compliance with the limits in Table 4 of this subpart using the procedures in paragraphs (c)(1) and (2) of this section. (1) Annual emissions of TF , and/or POM , and/or PM from a given number of anode bake furnaces making up each averaging31 group shall not exceed the applicable emission limit in Table 34 of this subpart in any one year; and (2) To determine compliance with the applicable emission limit in Table 34 of this subpart for anode bake furnaces, the owner or operator shall determine TF and/or POM TF, POM and/or
PM emissions from the control device for each furnace at least once a year using the procedures and methods in §§63.847 and 63.849. (d) Implementation plan. The owner or operator shall develop and submit an implementation plan for emission averaging to the applicable regulatory authority for review and approval according to the following procedures and requirements: (1) Deadlines. The owner or operator must submit the implementation plan no later than 6 months before the date that the facility intends to comply with the emission averaging limits. (2) Contents. The owner or operator shall include the following information in the implementation plan or in the application for an operating permit for all emission sources to be included in an emissions average: (i) The identification of all emission sources (potlines or anode bake furnaces) in the average; (ii) The assigned TF or POM , or PM emission limit for each averaging group of potlines or anode bake furnaces;32 (iii) The specific control technolog iesy or pollution prevention measure s to be used for each emission source in the averaging group and the date of its installation or application. If the pollution prevention measure s reduce s or eliminate s emissions from multiple sources, the owner or operator must identify each source; (iv) The test plan for the measurement of TF , or POM , or PM emissions in accordance with the requirements in §63.847(b); (v) The operating parameters to be monitored for each control system or device and a description of how the operating limits will be determined; (vi) If the owner or operator requests to monitor an alternative operating parameter pursuant to §63.848(l): (A) A description of the parameter(s) to be monitored and an explanation of the criteria used to select the parameter(s); and (B) A description of the methods and procedures that will be used to demonstrate that the parameter indicates proper operation of the control device; the frequency and content of monitoring, reporting, and recordkeeping requirements; and a demonstration, to the satisfaction of the applicable regulatory authority, that the proposed monitoring frequency is sufficient to represent control device operating conditions; and33 (vii) A demonstration that compliance with each of the applicable emission limit(s) will be achieved under representative operating conditions. (3) Approval criteria. Upon receipt, the regulatory authority shall review and approve or disapprove the plan or permit application according to the following criteria: (i) Whether the content of the plan includes all of the information specified in paragraph (d)(2) of this section; and (ii) Whether the plan or permit application presents sufficient information to determine that compliance will be achieved and maintained. (4) Prohibitions. The applicable regulatory authority shall not approve an implementation plan or permit application containing any of the following provisions: (i) Any averaging between emissions of differing pollutants or between differing sources. Emission averaging shall not be allowed between TF and POMTF, POM and/or PM , and emission averaging shall not be allowed between potlines and bake furnaces; (ii) The inclusion of any emission source other than an existing potline or existing anode bake furnace or the inclusion of any potline or anode bake plant not subject to the same operating permit; or34 (iii) The inclusion of any potline or anode bake furnace while it is shut down .; or (iv) The inclusion of any periods of startup, shutdown, or malfunction, as described in the startup, shutdown, and malfunction plan required by §63.850(c), in the emission calculations. (5) Term. Following review, the applicable regulatory authority shall approve the plan or permit application, request changes, or request additional information. Once the applicable regulatory authority receives any additional information requested, the applicable regulatory authority shall approve or disapprove the plan or permit application within 120 days. (i) The applicable regulatory authority shall approve the plan for the term of the operating permit; (ii) To revise the plan prior to the end of the permit term, the owner or operator shall submit a request to the applicable regulatory authority; and (iii) The owner or operator may submit a request to the applicable regulatory authority to implement emission averaging after the applicable compliance date. (6) Operation. While operating under an approved implementation plan, the owner or operator shall monitor the operating parameters of each control system, keep records, and35 submit periodic reports as required for each source subject to this subpart. **§ 63.847 Compliance provisions.** (a) Compliance dates . The owner or operator of a primary aluminum plant must comply with the requirements of this subpart by the applicable compliance date in paragraph (a)(1), (a)(2) or (a)(4) of this section : (1) October 7, 1999, for an owner or operator of an existing plant or source; (2) October 9, 2000, for an existing source, provided the owner or operator demonstrates to the satisfaction of the applicable regulatory authority that additional time is needed to install or modify the emission control equipment; (1) Except as noted in paragraph (2) of this section, the compliance date for an owner or operator of an existing plant or source subject to the provisions of this subpart is October 7, 1999. (2) The compliance dates for existing plants and sources

are: (i) **[Insert date of publication of final rule]** for the malfunction provisions of §§ 63.850(d)(2) and (e)(4)(xvi) and (xvii) and the electronic reporting provisions of §§ 63.850(b), (c) and (f) which became effective **[Insert date of publication of final rule]** 
.36 (ii) [ **Insert date 1 year after date of publication of final rule**  ] for potline work practice standards in § 63.854 and the COS emission limit provisions of § 63.843(e); for anode bake furnace startup practices in § 63.847(l) and PM emission limits in § 63.843(c)(3); for Soderberg potline PM and PCB emission limits in §§ 63.843(a)(3)(v) and (a)(6); and for paste production plant startup practices in § 63.847(m) and PM emission limits in § 63.843(b)(4) which became effective **[Insert date of publication of final rule]** 
. (iii) [ **Insert date 2 years after date of publication of final rule**  ] for prebake potline POM emission limits in §§ 63.843(a)(2)(iv) through (vii); for Soderberg potline POM, As and Ni emission limits in §§ 63.843(a)(2)(iii), (a)(4) and (5); for prebake potline PM emission limits in § 63.843(a)(3); for anode bake furnace Hg emission limits in § 63.843(c)(4); and for the pitch storage tank POM limit provisions of § 63.843(d) which became effective **[Insert date of publication of final rule]**
. (3) October 8, 2001, for an existing source that is granted an extension by the regulatory authority under section 112(i)(3)(B) of the Act; or[Reserved] (4) Upon startup, for an owner or operator of a new or reconstructed source.37 (5) Except as provided in paragraphs (a)(6) and (7) of this section, a new affected source is one for which construction or reconstruction commenced after September 26, 1996. (6) For the purposes of compliance with the emission standards for PM, a new affected potline, anode bake furnace or paste production plant is one for which construction or reconstruction commenced after December 8, 2014. (7) For the purposes of compliance with the emission standards for POM and COS, a new affected prebake potline is one for which construction or reconstruction commenced after December 8, 2014. (8) For the purposes of compliance with the emission standards for As, Ni and POM, a new affected Soderberg potline is one for which construction or reconstruction commenced after December 8, 2014. (9) For the purposes of compliance with the emission standards for Hg, a new affected anode bake furnace is one for which construction or reconstruction commenced after December 8, 2014. (b) Test plan. The owner or operator shall prepare a sitespecific test plan prior to the initial performance test according to the requirements of §63.7(c) of this part. The test plan must include procedures for conducting the initial performance test and for subsequent performance tests required38 in §63.848 for emission monitoring. In addition to the information required by §63.7, the test plan shall include: (1) Procedures to ensure a minimum of three runs are performed annually for the primary control system for each

source; (2) For a source with a single control device exhausted through multiple stacks, procedures to ensure that at least three runs are performed annually by a representative sample of the stacks satisfactory to the applicable regulatory authority; (3) For multiple control devices on a single source, procedures to ensure that at least one run is performed annually for each control device by a representative sample of the stacks satisfactory to the applicable regulatory authority; (4) Procedures for sampling single stacks associated with multiple anode bake furnaces; (5) For plants with roof scrubbers, procedures for rotating sampling among the scrubbers or other procedures to obtain representative samples as approved by the applicable regulatory authority; (6) For a VSS1 potline, procedures to ensure that one fan (or one scrubber) per potline is sampled for each run;[Reserved] (7) For a SWPB potline, procedures to ensure that the average of the sampling results for two fans (or two scrubbers) per potline is used for each run; and39 (8) Procedures for establishing the frequency of testing to ensure that at least one run is performed before the 15th of the month, at least one run is performed after the 15th of the month, and that there are at least 6 days between two of the runs during the month, or that secondary emissions are measured according to an alternate schedule satisfactory to the applicable regulatory authority. (c) Performance test dates . Following approval of the site-specific test plan, the owner or operator must conduct a performance test to demonstrate initial compliance according to the procedures in paragraph (d) of this section. If a performance test has been conducted on the primary control system for potlines , or for the anode bake furnace within the 12 months prior to the compliance date, the anode bake furnace, the paste production plant, or (if applicable) the pitch storage tank control device within the 12 months prior to the compliance date, the results of that performance test may be used to demonstrate initial compliance. The owner or operator must conduct the performance test: (1) During the first month following the compliance date for an existing potline (or potroom group) or anode bake furnace;, anode bake furnace, paste production plant or pitch storage tank.40 (2) By the date determined according to the requirements in paragraph (c)(2)(i), (ii), or (iii) or (iv) of this section for a new or reconstructed potline, anode bake furnace, or pitch storage tank (for which the owner or operator elects to conduct an initial performance test): (i) By the 180th day following startup for a potline or potroom group. The 180-day period starts when the first pot in a potline or potroom group is energized. (ii) By the 45th day from the start of the second anode bake cycle (but no later than the 180th day from the startup of the anode bake furnace). (iii) By the 30th day following startup for a pitch storage tank. The 30-day period starts when the tank is first used to store pitch. (iv) By the 30th day following startup of a paste production plant. The 30-day period starts when the paste production plant produces green anodes. (3) By the date determined according to the requirements in paragraph (c)(3)(i) or (ii) (ii), (iii) or (iv) of this section for an existing potline or anode bake furnace that was shut down at the time compliance would have otherwise been required and is subsequently restarted:41 (i) By the 180th day following startup for a potline or potroom group. The 180-day period starts when the first pot in a potline or potroom group is energized. (ii) By the 45th day from the start of the second anode bake cycle (but no later than the 180th day from the startup of the anode bake furnace). (iii) By the 30th day following startup of a paste production plant. The 30-day period starts when the paste production plant produces green anodes. (iv) By the 30th day following startup for a pitch storage tank. The 30-day period starts when the tank is first used to store pitch. (d) Performance test requirements. The initial performance test and all subsequent performance tests shall be conducted in accordance with the requirements of the general provisions in subpart A of this part, the approved test plan, and the procedures in this section. Performance tests must be conducted under such conditions as the Administrator specifies to the owner or operator based on representative performance of the affected source for the period being tested. Upon request, the owner or operator must make available to the Administrator such records as may be necessary to determine the conditions of performance tests.42 (1) TF emissions from potlines. For each potline, the owner or operator shall measure and record the emission rate of TF exiting the outlet of the primary control system for each potline and the rate of secondary emissions exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(1) of this section, the owner or operator shall compute and record the average of at least three runs each month for secondary emissions and at least three runs each year for the primary control system to determine compliance with the applicable emission limit. Compliance is demonstrated when the emission rate of TF is equal to or less than the applicable emission limit in §63.843, §63.844, or §63.846.(1) TF, POM and PM emissions from potlines. For each potline, the owner or operator shall measure and record the emission rates of TF, POM and PM exiting the outlet of the primary control system and the rate of secondary emissions exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(1) of this section, the owner or operator shall compute and record the average of at least three runs semiannually for secondary emissions and at least three runs each year for the primary control system to determine compliance with the applicable emission limit. Compliance is demonstrated when the emission rates of TF, POM, and PM are43 equal to or less than the applicable emission limits in § 63.843, § 63.844, or § 63.846. (2) POM emissions from Soderberg potlines. For each Soderberg (HSS, VSS1, and VSS2) potline, the owner or operator shall measure and record the emission rate of POM exiting the primary emission control system and the rate of secondary emissions exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(2) of this section, the owner or operator shall compute and record the average of at least three runs each quarter (one run per month) for secondary emissions and at least three runs each year for the primary control system to determine compliance with the applicable emission limit. Compliance is demonstrated when the emission rate of POM is equal to or less than the applicable emission limit in §63.843, §63.844, or §63.846.[Reserved] (3) Previous control device tests. If the owner or operator has performed more than one test of primary emission control device(s) for a potline or for a bake furnace during the previous consecutive 12 months, the average of all runs performed in the previous 12-month period shall be used to determine the contribution from the primary emission control system.44 (4) TF and POM emissions from anode bake furnaces. For each anode bake furnace, the owner or operator shall measure and record the emission rate of TF and POM exiting the exhaust stacks(s) of the primary emission control system for each anode bake furnace. Using the equations in paragraphs (e)(3) and (e)(4) of this section, the owner or operator shall compute and record the average of at least three runs each year to determine compliance with the applicable emission limits for TF and POM. Compliance is demonstrated when the emission rates of TF and POM are equal to or less than the applicable TF and POM emission limits in §63.843, §63.844, or §63.846.(4) TF, POM, PM and Hg emissions from anode bake furnaces. For each anode bake furnace, the owner or operator shall measure and record the emission rate of TF, POM, PM and Hg exiting the exhaust stacks(s) of the primary emission control system. In accordance with paragraphs (e)(3) and (4) of this section, the owner or operator shall compute and record the average of at least three runs each year to determine compliance with the applicable emission limits for TF, POM, PM and Hg. Compliance is demonstrated when the emission rates of TF, POM, PM and Hg are equal to or less than the applicable TF, POM, PM and Hg emission limits in § 63.843, § 63.844 or § 63.846. (5) Nickel emissions from VSS2 Potlines and new Soderberg potlines. (i) For each VSS2 potline, and for each new Soderberg45 potline, the owner or operator must measure and record the emission rate of nickel exiting the primary emission control system and the rate of secondary emissions of nickel exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(1) of this section, the owner or operator must compute and record the average of at least three runs each year for secondary emissions and at least three runs each year for primary emissions. (ii) Compliance is demonstrated when the emissions of nickel are equal to or less than the applicable emission limit in § 63.843(a)(4) or § 63.844(a)(4). (6) Arsenic emissions from VSS2 Potlines and from new Soderberg potlines. (i) For each VSS2 potline, and for each new Soderberg potline, the owner or operator must measure and record the emission rate of arsenic exiting the primary emission control system and the rate of secondary emissions of arsenic exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(1) of this section, the owner or operator must compute and record the average of at least three runs each year for secondary emissions and at least three runs each year for primary emissions.46 (ii) Compliance is demonstrated when the emissions of arsenic are equal to or less than the applicable emission limit in § 63.843(a)(5) or § 63.844(a)(5). (7) PCB emissions from VSS2 Potlines and from new Soderberg potlines. (i) For each VSS2 potline, and for each new Soderberg potline, the owner or operator must measure and record the emission rate of PCB exiting the primary emission control system and the rate of secondary emissions of PCB exiting through each roof monitor, or for a plant with roof scrubbers, exiting through the scrubbers. Using the equation in paragraph (e)(1) of this section, the owner or operator must compute and record the average of at least three runs each year for secondary emissions and at least three runs each year for primary emissions. (ii) Compliance is demonstrated when the emissions of PCB are equal to or less than the applicable emission limit in § 63.843(a)(6) or § 63.844(a)(6). (e) Equations. The owner or operator shall determine compliance with the applicable TF , and POM POM, PM, nickel, arsenic or PCB emission limits using the following equations and procedures: (1) Compute the emission rate (E p ) of TF from each potline using Equation 1:47 Where:
E p =emission rate of TF from a potline, kg/Mg (lb/ton);
C s1 =concentration of TF from the primary control system, mg/dscm (mg/dscf); Q sd =volumetric flow rate of effluent gas corresponding to the appropriate subscript location, dscm/hr (dscf/hr);
C s2 =concentration of TF as measured for roof monitor emissions, mg/dscm (mg/dscf); P=aluminum production rate, Mg/hr (ton/hr); K=conversion factor, 10 6 mg/kg (453,600 mg/lb);

1 = subscript for primary control system effluent gas; and

2 = subscript for secondary control system or roof monitor effluent gas. (1) Compute the emission rate (E p ) of TF, POM, PM, nickel, arsenic or PCB from each potline using Equation 1:

Where:
E p = emission rate of TF, POM, PM, nickel or arsenic from a potline, kg/Mg (lb/ton) (or μg TEQ/ton for PCB);
C s1 = concentration of TF, POM, PM, nickel or arsenic from the primary control system, mg/dscm (mg/dscf) (or μg TEQ/dscf for PCB);48 Q sd = volumetric flow rate of effluent gas corresponding to the appropriate subscript location, dscm/hr (dscf/hr);
C s2 = concentration of TF, POM, PM, nickel or arsenic as measured for roof monitor emissions, mg/dscm (mg/dscf) (or μg TEQ/dscf for PCB); P = aluminum production rate, Mg/hr (ton/hr); K = conversion factor, 10 6 mg/kg (453,600 mg/lb) for TF, POM, PM, nickel or arsenic (= 1 for PCB);

1 = subscript for primary control system effluent gas; and

2 = subscript for secondary control system or roof monitor effluent gas. (2) Compute the emission rate of POM from each potline using Equation 1, Where:
E p = emission rate of POM from the potline, kg/mg (lb/ton); and
C s = concentration of POM, mg/dscm (mg/dscf). POM emission data collected during the installation and startup of a cathode shall not be included in C s .[Reserved] (3) Compute the emission rate (E b ) of TF from each anode bake furnace using Equation 2,

Where:
E b = emission rate of TF, kg/mg (lb/ton) of green anodes produced;49 C s = concentration of TF, mg/dscm (mg/dscf); Q sd = volumetric flow rate of effluent gas, dscm/hr (dscf/hr);
P b = quantity of green anode material placed in the furnace, mg/hr (ton/hr); and K = conversion factor, 10 6 mg/kg (453,600 mg/lb). (4) Compute the emission rate of POM from each anode bake furnace using Equation 2, Where: C s = concentration of POM, mg/dscm (mg/dscf). (3) Compute the emission rate (E b ) of TF, POM or PM from each anode bake furnace using Equation 2,

Where:
E b = emission rate of TF, POM or PM, kg/mg (lb/ton) of green anodes; C s = concentration of TF, POM or PM, mg/dscm (mg/dscf); Q sd = volumetric flow rate of effluent gas, dscm/hr (dscf/hr);
P b = quantity of green anode material placed in the furnace, mg/hr (ton/hr); and K = conversion factor, 10 6 mg/kg (453,600 mg/lb). (4) Compliance with the anode bake furnace Hg emission standard is demonstrated if the Hg concentration of the exhaust from the anode bake furnace control device is equal to or less50 3 ) ( ) ( Equation K P Q C E b sd s PMpp    than the applicable concentration standard in § 63.843(c)(4) or § 63.844(c)(4). (5) Determine the weight of the aluminum tapped from the potline and the weight of the green anode material placed in the anode bake furnace using the monitoring devices required in §63.848(j). (6) Determine the aluminum production rate (P) by dividing the number of hours in the calendar month into the weight of aluminum tapped from the potline during the calendar month that includes the three runs of a performance test. (7) Determine the rate of green anode material introduced into the furnace by dividing the number of operating hours in the calendar month into the weight of green anode material used during the calendar month in which the performance test was conducted. (8) Compute the emission rate (E PMpp ) of PM from each paste production plant using Equation 3,

Where:
E PMpp = emission rate of PM, kg/mg (lb/ton) of green anode material exiting the paste production plant; C s = concentration of PM, mg/dscm (mg/dscf); Q sd = volumetric flow rate of effluent gas, dscm/hr (dscf/hr);51 P b = quantity of green anode material exiting the paste production plant, mg/hr (ton/hr); and K = conversion factor, 10 6 mg/kg (453,600 mg/lb). (f) Paste production plants. (1) Initial compliance with the standards for existing and new paste production plants in §§63.843(b) and 63.844(b) will be demonstrated through site inspection(s) and review of site records by the applicable regulatory authority. (2) For each paste production plant, the owner or operator shall measure and record the emission rate of PM exiting the exhaust stacks(s) of the primary emission control system. Using the equation in paragraph (e)(8) of this section, the owner or operator shall compute and record the average of at least three runs each year to determine compliance with the applicable emission limits for PM. Compliance with the PM standards for existing and new paste production plants is demonstrated when the PM emission rates are less than or equal to the applicable PM emission limits in §§ 63.843(b)(4) and 63.844(b)(2). (g) Pitch storage tanks. The owner or operator shall demonstrate initial compliance with the standard for pitch storage tanks in § § 63.843(d) and 63.844(d) by preparing a design evaluation or by conducting a performance test. The owner or operator shall submit for approval by the regulatory authority the information specified in paragraph (g)(1) of this52 section, along with the information specified in paragraph (g)(2) of this section where a design evaluation is performed or the information specified in paragraph (g)(3) of this section where a performance test is conducted. (1) A description of the parameters to be monitored to ensure that the control device is being properly operated and maintained, an explanation of the criteria used for selection of that parameter (or parameters), and the frequency with which monitoring will be performed; and (2) Where a design evaluation is performed, documentation demonstrating that the control device used achieves the required control efficiency during reasonably expected maximum filling rate. The documentation shall include a description of the gas stream that enters the control device, including flow and POM content under varying liquid level conditions, and the information specified in paragraphs (g)(2)(i) through (g)(2)(vi) of this section, as applicable. (i) If the control device receives vapors, gases, or liquids, other than fuels, from emission points other than pitch storage tanks, the efficiency demonstration is to include consideration of all vapors, gases, and liquids, other than fuels, received by the control device; (ii) If an enclosed combustion device with a minimum residence time of 0.5 seconds and a minimum temperature of 76053 °C (1,400 °F) is used to meet the emission reduction requirement specified in § 63.843(d) and § 63.844(d), documentation that those conditions exist is sufficient to meet the requirements of § 63.843(d) and §63.844(d); (iii) Except as provided in paragraph (g)(2)(ii) of this section, for thermal incinerators, the design evaluation shall include the autoignition temperature of the organic HAP, the flow rate of the organic HAP emission stream, the combustion temperature, and the residence time at the combustion temperature; (iv) If the pitch storage tank is vented to the emission control system installed for control of emissions from the paste production plant pursuant to §63.843(b) or §63.844(b)(1) , documentation of compliance with the requirements of §63.843(b) is sufficient to meet the requirements of § 63.843(d) or §63.844(d); (v) For carbon adsorbers, the design evaluation shall include the affinity of the organic vapors for carbon, the amount of carbon in each bed, the number of beds, the humidity of the feed gases, the temperature of the feed gases, the flow rate of the organic HAP emission stream, and if applicable, the desorption schedule, the regeneration stream pressure or temperature, and the flow rate of the regeneration stream. For vacuum desorption, the pressure drop shall be included; and54 (vi) For condensers, the design evaluation shall include the final temperature of the organic HAP vapors, the type of condenser, and the design flow rate of the organic HAP emission
stream. (3) If a performance test is conducted, the owner or operator shall determine the control efficiency for POM during tank loading using Method 315 in appendix A to this part. The owner or operator shall include the following information: (i) Identification of the pitch storage tank and control device for which the performance test will be submitted; and (ii) Identification of the emission point(s) that share the control device with the pitch storage tank and for which the performance test will be conducted. (h) Selection of monitoring parameters. The owner or operator shall determine the operating limits and monitoring frequency for each control device that is to be monitored as required in §63.848(f). (1) For potlines and anode bake furnaces, the owner or operator shall determine upper and/or lower operating limits, as appropriate, for each monitoring device for the emission control system from the values recorded during each of the runs performed during the initial performance test and from historical data from previous performance tests conducted by the methods specified in this subpart.55 (2) For a paste production plant, the owner or operator shall specify and provide the basis or rationale for selecting parameters to be monitored and the associated operating limits for the emission control device. (3) The owner or operator may redetermine the upper and/or lower operating limits, as appropriate, based on historical data or other information and submit an application to the applicable regulatory authority to change the applicable limit(s). The redetermined limits shall become effective upon approval by the applicable regulatory authority. (i) [Reserved] (j) Carbonyl sulfide (COS) emissions. The owner operator must calculate, for each potline, the emission rate of COS for each calendar month of operation using Equation 4: 

##     ) 4 ( Equation S Z Y K E COS 

###          

Where:
E COS = the emission rate of COS during the calendar month, pounds per ton of aluminum produced; K = factor accounting for molecular weights and conversion of sulfur to carbonyl sulfide = 234; Y = the mass of anode consumed in the potline during the calendar month, tons;56 Z = the mass of aluminum produced by the potline during the calendar month, tons; and S = the weighted average fraction of sulfur in the anode coke consumed in the production of aluminum during the calendar month (e.g., if the weighted average sulfur content of the anode coke consumed during the calendar month was 2.5 percent, then S = 0.025). The weight of anode coke used during the calendar month of each different concentration of sulfur is used to calculate the overall weighted average fraction of sulfur. Compliance is demonstrated if the calculated value of E COS is less than the applicable standard for COS emissions in §§ 63.843(e) and 63.844(e). (k) Startup of potlines. The owner or operator must develop a written startup plan as described in § 63.854(b) that contains specific procedures to be followed during startup periods of potline(s). Compliance with the applicable standards in § 63.854(b) will be demonstrated through site inspection(s) and review of site records by the regulatory authority. (l) Startup of anode bake furnaces. The owner or operator must develop a written startup plan as described in paragraphs (l)(1) through (4) of this section, to be followed during startup periods of bake furnaces. Compliance with the startup plan will be demonstrated through site inspection(s) and review of site records by the regulatory authority. The written startup57 plan must contain specific procedures to be followed during startup periods of anode bake furnaces, including the following: (1) A requirement to develop an anode bake furnace startup schedule. (2) Records of time, date, duration of anode bake furnace startup and any nonroutine actions taken during startup of the furnaces. (3) A requirement that the associated emission control system be operating within normal parametric limits prior to startup of the anode bake furnace. (4) A requirement to take immediate actions to stop the startup process as soon as practicable and continue to comply with § 63.843(f) or § 63.844(f) if the associated emission control system is off line at any time during startup. The anode bake furnace restart may resume once the associated emission control system is back on line and operating within normal parametric limits. (m) Startup of paste production plants. The owner or operator must develop a written startup plan as described in paragraphs (m)(1) through (3) of this section, to be followed during startup periods for paste production plants. Compliance with the startup plan will be demonstrated through site inspection(s) and review of site records by the regulatory authority. The written startup plan must contain specific58 procedures to be followed during startup periods of paste production plants, including the following: (1) Records of time, date, duration of paste production plant startup and any nonroutine actions taken during startup of the paste production plants. (2) A requirement that the associated emission control system be operating within normal parametric limits prior to startup of the paste production plant. (3) A requirement to take immediate actions to stop the startup process as soon as practicable and continue to comply with § 63.843(f) or § 63.844(f) if the associated emission control system is off line at any time during startup. The paste production plant restart may resume once the associated emission control system is back on line and operating within normal parametric limits. **§ 63.848 Emission monitoring requirements.** (a) TF emissions from potlines. Using the procedures in §63.847 and in the approved test plan, the owner or operator shall monitor emissions of TF from each potline by conducting monthly performance tests. The owner or operator shall compute and record the monthly average from at least three runs for secondary emissions and the previous 12-month average of all runs for the primary control system to determine compliance with the applicable emission limit. The owner or operator must59 include all valid runs in the monthly average. The duration of each run for secondary emissions must represent a complete operating cycle. (b) POM emissions from Soderberg potlines. Using the procedures in §63.847 and in the approved test plan, the owner or operator shall monitor emissions of POM from each Soderberg (HSS, VSS1, and VSS2) potline every three months. The owner or operator shall compute and record the quarterly (3-month) average from at least one run per month for secondary emissions and the previous 12-month average of all runs for the primary control systems to determine compliance with the applicable emission limit. The owner or operator must include all valid runs in the quarterly (3-month) average. The duration of each run for secondary emissions must represent a complete operating cycle. The primary control system must be sampled over an 8-hour period, unless site-specific factors dictate an alternative sampling time subject to the approval of the regulatory authority. (c) TF and POM emissions from anode bake furnaces. Using the procedures in §63.847 and in the approved test plan, the owner or operator shall monitor TF and POM emissions from each anode bake furnace on an annual basis. The owner or operator shall compute and record the annual average of TF and POM emissions from at least three runs to determine compliance with60 the applicable emission limits. The owner or operator must include all valid runs in the annual average. (d) Similar potlines. As an alternative to monthly monitoring of TF or POM secondary emissions from each potline using the test methods in §63.849, the owner or operator may perform monthly monitoring of TF or POM secondary emissions from one potline using the test methods in §§63.849 (a) or (b) to represent the performance of similar potline(s). The similar potline(s) shall be monitored using an alternative method that meets the requirements of paragraphs (d)(1) through (d)(7) of this section. Two or more potlines are similar if the owner or operator demonstrates that their structure, operability, type of emissions, volume of emissions, and concentration of emissions are substantially equivalent. (a) TF and PM emissions from potlines. Using the procedures in § 63.847 and in the approved test plan, the owner or operator shall monitor emissions of TF and PM from each potline by conducting annual performance tests on the primary control system and semiannual performance tests on the secondary emissions. The owner or operator shall compute and record the average semiannually from at least three runs for secondary emissions and the average from at least three runs for the primary control system to determine compliance with the applicable emission limit. The owner or operator must include61 all valid runs in the semiannual average. The duration of each run for secondary emissions must represent a complete operating cycle. Potline emissions shall be recorded as the sum of the average of at least three runs from the primary control system and the average of at least three runs from the roof monitor or secondary emissions control device. (b) POM emissions from potlines. Using the procedures in § 63.847 and in the approved test plan, the owner or operator must monitor emissions of POM from each potline stack annually and secondary potline POM emissions semiannually. The owner or operator must compute and record the semiannual average from at least three runs for secondary emissions and at least three runs for the primary control systems to determine compliance with the applicable emission limit. The owner or operator must include all valid runs in the semiannual average. The duration of each run for secondary emissions must represent a complete operating cycle. The primary control system must be sampled over an 8-hour period, unless site-specific factors dictate an alternative sampling time subject to the approval of the regulatory authority. Potline emissions shall be recorded as the sum of the average of at least three runs from the primary control system and the average of at least three runs from the roof monitor or secondary emissions control device.62 (c) TF, PM, Hg and POM emissions from anode bake furnaces. Using the procedures in §63.847 and in the approved test plan, the owner or operator shall determine TF, PM, Hg and POM emissions from each anode bake furnace on an annual basis. The owner or operator shall compute and record the annual average of TF, PM, Hg and POM emissions from at least three runs to determine compliance with the applicable emission limits. A minimum of four dscm per run must be collected for monitoring of Hg emissions. The owner or operator must include all valid runs in the annual average. (d) Similar potlines. As an alternative to semiannual monitoring of TF, POM or PM secondary emissions from each potline using the methods in § 63.849, the owner or operator may perform semiannual monitoring of TF, POM or PM secondary emissions from one potline using the test methods in § 63.849(a) or (b) to represent the performance of similar potline(s). The similar potline(s) must be monitored using an alternative method that meets the requirements of (d)(1) through (d)(7) of this section. Two or more potlines are similar if the owner or operator demonstrates that their structure, operability, type of emissions, volume of emissions and concentration of emissions are substantially equivalent. (1) To demonstrate (to the satisfaction of the regulatory authority) that the level of emission control performance is the63 same or better, the owner or operator shall perform an emission test using an alternative monitoring procedure for the similar potline simultaneously with an emission test using the applicable test methods. The results of the emission test using the applicable test methods must be in compliance with the applicable emission limit for existing or new potlines in §63.843 or §63.844. An alternative method: (i) For TF emissions, must account for or include gaseous fluoride and cannot be based on measurement of particulate matter or particulate fluoride alone; and (ii) For TF , and POM and PM emissions, must meet or exceed Method 14 criteria. (2) An HF continuous emission monitoring system is an approved alternative for the monitoring of TF secondary emissions. (3) An owner or operator electing to use an alternative monitoring procedure shall establish an alternative emission limit based on at least nine simultaneous runs using the applicable test methods and the alternative monitoring method. All runs must represent a full process cycle. (4) The owner or operator shall derive an alternative emission limit for the HF continuous emission monitor or an alternative method using either of the following procedures:64 (i) Use the highest value from the alternative method associated with a simultaneous run by the applicable test method that does not exceed the applicable emission limit; or (ii) Correlate the results of the two methods (the applicable test method results and the alternative monitoring method results) and establish an emission limit for the alternative monitoring system that corresponds to the applicable emission limit. (5) The owner or operator shall submit the results required in paragraph (d)(4) of this section and all supporting documentation to the applicable regulatory authority for review and approval. (6) The regulatory authority shall review and approve or disapprove the request for an alternative method and alternative emission limit. The criterion for approval shall be a demonstration (to the satisfaction of the regulatory authority) that the alternative method and alternative emission limit achieve a level of emission control that is the same as or better than the level that would have otherwise been achieved by the applicable method and emission limit. (7) If the alternative method is approved by the applicable regulatory authority, the owner or operator shall perform monthly semiannual emission monitoring using the approved65 alternative monitoring procedure to demonstrate compliance with the alternative emission limit for each similar potline. (e) Reduced sampling frequency. The owner or operator may submit a written request to the applicable regulatory authority to establish an alternative testing requirement to reduce the sampling of secondary TF emissions from potlines from monthly to quarterly. (1) In the request, the owner or operator shall provide information and data demonstrating, to the satisfaction of the applicable regulatory authority, that secondary emissions of TF from potlines have low variability during normal operations using the procedures in paragraphs (e)(1)(i) or (e)(1)(ii) of this section. (i) Submit data from 24 consecutive months of sampling that show the average TF emissions are less than 60 percent of the applicable limit and that no monthly performance test in the 24 months of sampling exceeds 75 percent of the applicable limit;

or (ii) Submit data and a statistical analysis that the regulatory authority may evaluate based on the approach used in “Primary Aluminum: Statistical Analysis of Potline Fluoride Emissions and Alternative Sampling Frequency” (EPA–450–86–012, October 1986), which is available from the National Technical66 Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161. (2) An approved alternative requirement must include a test schedule and the method to be used to measure emissions for performance tests. (3) The owner or operator of a plant that has received approval of an alternative sampling frequency under §60.194 of this chapter is deemed to have approval of the alternative sampling frequency under this subpart. (4) If emissions in excess of the applicable TF limit occur while performing quarterly sampling approved under paragraph (e)(1)(i) of this section, the owner or operator shall return to monthly sampling for at least 12 months and may reduce to quarterly sampling when: (i) The average of all tests performed over the most recent 24-month period does not exceed 60 percent of the applicable limit, and (ii) No more than one monthly performance test in the most recent 24-month period exceeds 75 percent of the applicable limit. (5) If emissions in excess of the applicable TF limit occur while performing quarterly sampling approved under paragraph (e)(1)(ii) of this section, the owner or operator shall immediately return to the monthly sampling schedule required by67 paragraph (a) of this section until another request for an alternative sampling frequency is approved by the applicable regulatory authority.[Reserved] (f) Monitoring parameters for emission control devices. The owner or operator shall install, operate, calibrate, and maintain a continuous parameter monitoring system for each emission control device. The owner or operator shall submit for approval by the regulatory authority a description of the parameter(s) to be monitored, the operating limits, and the monitoring frequency to ensure that the control device is being properly operated and maintained. An explanation of the criteria used for selection of the parameter(s), the operating limits, and the monitoring frequency, including how these relate to emission control also shall be submitted to the regulatory authority. Except as provided in paragraph (l) of this section, the following monitoring devices shall be installed: (1) For dry alumina scrubbers, devices for the measurement of alumina flow and air flow; (2) For dry coke scrubbers, devices for the measurement of coke flow and air flow; (3) For wet scrubbers as the primary control system, devices for the measurement of water flow and air flow; (4) For electrostatic precipitators, devices for the measurement of voltage and secondary current; and68 (5) For wet roof scrubbers for secondary emission control: (i) A device for the measurement of total water flow; and (ii) The owner or operator shall inspect each control device at least once each operating day to ensure the control device is operating properly and record the results of each inspection. (6) For emission sources control device exhaust streams for which the owner or operator chooses to demonstrate continuous compliance through bag leak detection systems you must install and operate a bag leak detection system according to the requirements in paragraph (o) of this section, and you must set your operating limit such that the sum of the durations of bag leak detection system alarms does not exceed 5 percent of the process operating time during a 6-month period. (7) For emission sources control device exhaust streams for which the owner or operator chooses to demonstrate continuous compliance through a PM CEMS, you must install and operate a PM CEMS according to the requirements in paragraph (p) of this section. You must determine continuous compliance averaged on a rolling 30 operating day basis, updated at the end of each new operating day. All valid hours of data from 30 successive operating days shall be included in the arithmetic average. Compliance is demonstrated when the 30 operating day PM69 emissions are equal to or less than the applicable emission limits in § 63.843, § 63.844, or § 63.846. (g) Visible emissions. The owner or operator shall visually inspect the exhaust stack(s) of each control device on a daily basis for evidence of any visible emissions indicating abnormal operation.The owner or operator of a new or reconstructed affected source that is subject to a PM limit shall comply with the requirements of either paragraph (f)(6) or (f)(7) of this section. The owner or operator of an existing affected source that is equipped with a control device and is subject to a PM limit shall: (1) Install and operate a bag leak detection system in accordance with paragraph (f)(6) of this section; or (2) Install and operate a PM CEMS in accordance with paragraph (f)(7) of this section; or (3) Visually inspect the exhaust stack(s) of each fabric filter using Method 22 on a twice daily basis (at least 4 hours apart) for evidence of any visible emissions indicating abnormal operations and, must initiate corrective actions within 1 hour of a visible emissions inspection that indicates abnormal operation. Corrective actions shall include, at a minimum, isolating, shutting down and conducting an internal inspection of the baghouse compartment that is the source of the visible emissions that indicate abnormal operations.70 (h) Corrective action. If a monitoring device for a primary control device measures an operating parameter outside the limit(s) established pursuant to §63.847(h), if visible emissions indicating abnormal operation are observed from the exhaust stack of a control device during a daily inspection, or if a problem is detected during the daily inspection of a wet roof scrubber for potline secondary emission control, the owner or operator shall initiate corrective action procedures within 1 hour. Failure to initiate the corrective action procedures within 1 hour or to take the necessary corrective actions to remedy the problem is a violation. (i) Exceedances. If the limit for a given operating parameter associated with monitoring a specific control device is exceeded six times in any semiannual reporting period, then any subsequent exceedance in that reporting period is a violation. For the purpose of determining the number of exceedances, no more than one exceedance shall be attributed in any given 24-hour period. (j) Weight of aluminum and green anodes. The owner or operator of a new or existing potline or anode bake furnace shall install, operate, and maintain a monitoring device to determine the daily weight of aluminum produced and the weight of green anode material placed in the anode bake furnace. The weight of green anode material may be determined by monitoring71 the weight of all anodes or by monitoring the number of anodes placed in the furnace and determining an average weight from measurements of a representative sample of anodes. (k) Accuracy and calibration. The owner or operator shall submit recommended accuracy requirements to the regulatory authority for review and approval. All monitoring devices required by this section must be certified by the owner or operator to meet the accuracy requirements and must be calibrated in accordance with the manufacturer's instructions. (l) Alternative operating parameters. The owner or operator may monitor alternative control device operating parameters subject to prior written approval by the applicable regulatory authority. (m) Other control systems. An owner or operator using a control system not identified in this section shall request that the applicable regulatory authority include the recommended parameters for monitoring in the facility's part 70 permit. (n) PM emissions from paste production plants. Using the procedures in § 63.847 and in the approved test plan, the owner or operator shall monitor PM emissions from each paste production plant on an annual basis. The owner or operator shall compute and record the annual average of PM emissions from at least three runs to determine compliance with the applicable72 emission limits. The owner or operator must include all valid runs in the annual average. (o) Bag leak detection system. For each new affected source subject to a PM emissions limit, you must install, operate and maintain a bag leak detection system according to paragraphs (o)(1) through (3) of this section, unless a system meeting the requirements of paragraph (p) of this section, for a CEMS, is installed for monitoring the concentration of PM. (1) You must develop and implement written procedures for control device maintenance that include, at a minimum, a preventative maintenance schedule that is consistent with thecontrol device manufacturer's instructions for routine and longterm maintenance. (2) Each bag leak detection system must meet the specifications and requirements in paragraphs (o)(2)(i) through (viii) of this section. (i) The bag leak detection system must be certified by the manufacturer to be capable of detecting PM emissions at concentrations of 1.0 milligram per dry standard cubic meter (0.00044 grains per actual cubic foot) or less. (ii) The bag leak detection system sensor must provide output of relative PM loadings.73 (iii) The bag leak detection system must be equipped with an alarm system that will alarm when an increase in relative particulate loadings is detected over a preset level. (iv) You must install, calibrate, operate and maintain the bag leak detection system according to the manufacturer's written specifications and recommendations. (v) The initial adjustment of the system must, at a minimum, consist of establishing the baseline output by adjusting the sensitivity (range) and the averaging period of the device and establishing the alarm set points and the alarm delay time. (vi) Following initial adjustment, you must not adjust the sensitivity or range, averaging period, alarm set points, or alarm delay time, except in accordance with the procedures developed under paragraph (o)(1) of this section. You cannot increase the sensitivity by more than 100 percent or decrease the sensitivity by more than 50 percent over a 365-day period unless such adjustment follows a complete PM control device inspection that demonstrates that the PM control device is in good operating condition. (vii) You must install the bag leak detector downstream of the PM control device.74 (viii) Where multiple detectors are required, the system's instrumentation and alarm may be shared among detectors. (3) You must include in the written procedures required by paragraph (o)(1) of this section a corrective action plan that specifies the procedures to be followed in the case of a bag leak detection system alarm. The corrective action plan must include, at a minimum, the procedures that you will use to determine and record the time and cause of the alarm as well as the corrective actions taken to minimize emissions as specified in paragraphs (o)(3)(i) and (ii) of this section. (i) The procedures used to determine the cause of the alarm must be initiated within 1 hour of the alarm. (ii) The cause of the alarm must be alleviated by taking the necessary corrective action(s) that may include, but not be limited to, those listed in paragraphs (o)(3)(ii)(A) through (F) of this section. (A) Inspecting the PM control device for air leaks, torn or broken filter elements, or any other malfunction that may cause an increase in emissions. (B) Sealing off defective bags or filter media. (C) Replacing defective bags or filter media, or otherwise repairing the control device. (D) Sealing off a defective baghouse compartment.75 (E) Cleaning the bag leak detection system probe, or otherwise repairing the bag leak detection system. (F) Shutting down the process producing the particulate emissions. (p) Particulate Matter CEMS. If you are using a CEMS to measure particulate matter emissions to meet requirements of this subpart, you must install, certify, operate and maintain the particulate matter CEMS as specified in paragraphs (p)(1) through (4) of this section. (1) You must conduct a performance evaluation of the PM CEMS according to the applicable requirements of § 60.13, and Performance Specification 11 at 40 CFR part 60, Appendix B of this chapter. (2) During each PM correlation testing run of the CEMS required by Performance Specification 11 at 40 CFR part 60, Appendix B of this chapter, collect data concurrently by both the CEMS and by conducting performance tests using Method 5, 5D or 5I at 40 CFR part 60, Appendix A–3. (3) Operate and maintain the CEMS in accordance with Procedure 2 at 40 CFR part 60, Appendix F of this chapter. Relative Response Audits must be performed annually and Response Correlation Audits must be performed every three years. **§ 63.849 Test methods and procedures.**76 (a) The owner or operator shall use the following reference methods to determine compliance with the applicable emission limits for TF , and POM emissionsPOM, PM, Ni, As, Hg, PCB and conduct visible emissions observations : (1) Method 1 in appendix A to part 60 of this chapter for sample and velocity traverses; (2) Method 2 in appendix A to part 60 of this chapter for velocity and volumetric flow rate; (3) Method 3 in appendix A to part 60 of this chapter for gas analysis; (4) Method 13A or Method 13B in appendix A to part 60 of this chapter, or an approved alternative, for the concentration of TF where stack or duct emissions are sampled; (5) Method 13A or Method 13B and Method 14 or Method 14A in appendix A to part 60 of this chapter or an approved alternative method for the concentration of TF where emissions are sampled from roof monitors not employing wet roof scrubbers; (6) Method 315 in appendix A to this part or an approved alternative method for the concentration of POM where stack or duct emissions are sampled; and (7) Method 315 in appendix A to this part and Method 14 or 14A in appendix A to part 60 of this chapter or an approved alternative method for the concentration of POM where emissions are sampled from roof monitors not employing wet roof scrubbers.77 Method 315 need not be set up as required in the method. Instead, when using Method 14A, replace the Method 14A monitor cassette filter with the filter specified by Method 315. Recover and analyze the filter according to Method 315. When using Method 14, test at ambient conditions, do not heat the filter and probe, and do not analyze the back half of the sampling train; (8) Method 5 in appendix A to part 60 of this chapter or an approved alternative method for the concentration of PM where stack or duct emissions are sampled; (9) Method 17 and Method 14 or Method 14A in appendix A to part 60 of this chapter or an approved alternative method for the concentration of PM where emissions are sampled from roof monitors not employing wet roof scrubbers. Method 17 need not be set up as required in the method. Instead, when using Method 14A, replace the Method 14A monitor cassette filter with the filter specified by Method 17. Recover and analyze the filter according to Method 17. When using Method 14, test at ambient conditions, do not heat the filter and probe, and do not analyze the back half of the sampling train; (10) Method 29 in appendix A to part 60 of this chapter or an approved alternative method for the concentration of mercury, nickel and arsenic where stack or duct emissions are sampled;78 (11) Method 29 and Method 14 or Method 14A in appendix A to part 60 of this chapter or an approved alternative method for the concentration of nickel and arsenic where emissions are sampled from roof monitors not employing wet roof scrubbers. Method 29 need not be set up as required in the method. Instead, replace the Method 14A monitor cassette filter with the filter specified by Method 29. Recover and analyze the filter according to Method 29. When using Method 14, test at ambient conditions, do not heat the filter and probe, and do not analyze the back half of the sampling train; (12) Method 22 in Appendix A to part 60 of this chapter or an approved alternative method for determination of visual emissions; (13) Method 428 of the California Air Resources Board (incorporated by reference; see § 63.14) for the measurement of PCB where stack or duct emissions are sampled; and (14) Method 428 of the California Air Resources Board (incorporated by reference; see § 63.14) and Method 14 or Method 14A in appendix A to part 60 of this chapter or an approved alternative method for the concentration of PCB where emissions are sampled from roof monitors not employing wet roof scrubbers. (b) The owner or operator of a VSS potline or a SWPB potline equipped with wet roof scrubbers for the control of secondary emissions shall use methods that meet the intent of79 the sampling requirements of Method 14 in appendix A to part 60 of this chapter and that are approved by the State. Sample analysis shall be performed using Method 13A or Method 13B in appendix A to part 60 of this chapter for TF, Method 315 in appendix A to this part for POM, or an approved alternative method. (c) Except as provided in §63.845(g)(1), references to “potroom” or “potroom group” in Method 14 in appendix A to part 60 of this chapter shall be interpreted as “potline” for the purposes of this subpart. (d) For sampling using Method 14 in appendix A to part 60 of this chapter, the owner or operator shall install one Method 14 manifold per potline in a potroom that is representative of the entire potline, and this manifold shall meet the installation requirements specified in section 2.2.1 of Method 14 in appendix A to part 60 of this chapter. (e) The owner or operator may use an alternative test method for TF or POM emissions providing: (1) The owner or operator has already demonstrated the equivalency of the alternative method for a specific plant and has received previous approval from the Administrator or the applicable regulatory authority for TF or POM measurements using the alternative method; or80 (2) The owner or operator demonstrates to the satisfaction of the applicable regulatory authority that the results from the alternative method meet the criteria specified in §§63.848(d)(1) and (d)(3) through (d)(6). The results from the alternative method shall be based on simultaneous sampling using the alternative method and the following reference methods: (i) For TF, Methods 13 and 14 or Method 14A in appendix A to part 60 of this chapter; or (ii) For POM, Method 315 in appendix A to this part and Method 14 in appendix A to part 60 of this chapter. (f) The owner or operator must use either ASTM D4239-14e1 or ASTM D6376-10 (incorporated by reference; see § 63.14) for determination of the sulfur content in anode coke shipments to determine compliance with the applicable emission limit for COS emissions. **§ 63.850 Notification, reporting, and recordkeeping requirements.**  (a) Notifications. The owner or operator shall submit the following written notifications: (1) Notification for an area source that subsequently increases its emissions such that the source is a major source subject to the standard;81 (2) Notification that a source is subject to the standard, where the initial startup is before the effective date of the standard; (3) Notification that a source is subject to the standard, where the source is new or has been reconstructed, the initial startup is after the effective date of the standard, and for which an application for approval of construction or reconstruction is not required; (4) Notification of intention to construct a new major source or reconstruct a major source; of the date construction or reconstruction commenced; of the anticipated date of startup; of the actual date of startup, where the initial startup of a new or reconstructed source occurs after the effective date of the standard, and for which an application for approval of construction or reconstruction is required [see §§63.9(b)(4) and (b)(5)]; (5) Notification of initial performance test; (6) Notification of initial compliance status; (7) One-time notification for each affected source of the intent to use an HF continuous emission monitor; (8) Notification of compliance approach. The owner or operator shall develop and submit to the applicable regulatory authority, if requested, an engineering plan that describes the techniques that will be used to address the capture efficiency82 of the reduction cells for gaseous hazardous air pollutants in compliance with the emission limits in §§63.843, 63.844, and 63.846; and (9) One-time notification of startup of an existing potline or potroom group, anode bake furnace, or paste production plant that was shut down for a long period and subsequently restarted. The owner or operator must provide written notice to the Administrator at least 30 days before the startup. (b) Performance test reports. The owner or operator shall report the results of the initial performance test as part of the notification of compliance status required in paragraph (a)(6) of this section. Except as provided in paragraph (d) of this section, the owner or operator shall submit a summary of all subsequent performance tests to the applicable regulatory authority on an annual basis. Within 60 days after the date of completing each performance test (as defined in § 63.2) required by this subpart, you must submit the results of the performance tests following the procedure specified in either paragraph (b)(1) or (b)(2) of this section. (1) For data collected using test methods supported by the EPA’s Electronic Reporting Tool (ERT) as listed on the EPA’s ERT Web site (http://www.epa.gov/ttn/chief/ert/index.html) at the time of the test, you must submit the results of the performance test to the EPA via the Compliance and Emissions Data Reporting83 Interface (CEDRI). CEDRI can be accessed through the EPA’s Central Data Exchange (CDX) (https://cdx.epa.gov/epa_home.asp). Performance test data must be submitted in a file format generated through the use of the EPA’s ERT. Alternatively, you may submit performance test data in an electronic file format consistent with the extensible markup language (XML) schema listed on the EPA’s ERT Web site once the XML schema is available. If you claim that some of the performance test information being submitted is confidential business information (CBI), you must submit a complete file generated through the use of the EPA’s ERT or an alternate electronic file consistent with the XML schema listed on the EPA’s ERT Web site, including information claimed to be CBI, on a compact disc, flash drive, or other commonly used electronic storage media to the EPA. The electronic media must be clearly marked as CBI and mailed to U.S. EPA/OAQPS/CORE CBI Office, Attention: Group Leader, Measurement Policy Group, MD C404-02, 4930 Old Page Rd., Durham, NC 27703. The same ERT or alternate file with the CBI omitted must be submitted to the EPA via the EPA’s CDX as described earlier in this paragraph. (2) For data collected using test methods that are not supported by the EPA’s ERT as listed on the EPA’s ERT Web site at the time of the test, you must submit the results of the84 performance test to the Administrator at the appropriate address listed in § 63.13. (3) For data collected which requires summation of results from both ERT and non-ERT supported test methods in order to demonstrate compliance with an emission limit, you must submit the results of the performance test(s) used to demonstrate compliance with that emission limit to the Administrator at the appropriate address listed in § 63.13. (c) Startup, shutdown, and malfunction plan and reports. The owner or operator shall develop a written plan as described in §63.6(e)(3) that contains specific procedures to be followed for operating the source and maintaining the source during periods of startup, shutdown, and malfunction and a program of corrective action for malfunctioning process and control systems used to comply with the standards. The plan does not have to be submitted with the permit appplication or included in the operating permit. The permitting authority may review the plan upon request. In addition to the information required in §63.6(e)(3), the plan shall include: (1) Procedures, including corrective actions, to be followed if a monitoring device measures an operating parameter outside the limit(s) established under §63.847(h), if visible emissions from an exhaust stack indicating abnormal operation of a control device are observed by the owner or operator during85 the daily inspection required in §63.848(g), or if a problem is detected during the daily inspection of a wet roof scrubber for potline secondary emission control required in §63.848(f)(5)(ii); and (2) The owner or operator shall also keep records of each event as required by §63.10(b) and record and report if an action taken during a startup, shutdown, or malfunction is not consistent with the procedures in the plan as described in §63.6(e)(3)(iv). (c) Performance evaluation reports. Within 60 days after the date of completing each continuous emissions monitoring system performance evaluation (as defined in § 63.2), you must submit the results of the performance evaluation following the procedure specified in either paragraph (c)(1) or (c)(2) of this section. (1) For performance evaluations of continuous monitoring systems measuring relative accuracy test audit (RATA) pollutants that are supported by the EPA’s ERT as listed on the EPA’s ERT Web site at the time of the test, you must submit the results of the performance evaluation to the EPA via the CEDRI. (CEDRI can be accessed through the EPA’s CDX.) Performance evaluation data must be submitted in a file format generated through the use of the EPA’s ERT. Alternatively, you may submit performance evaluation data in an electronic file format consistent with the86 XML schema listed on the EPA’s ERT Web site once the XML schema is available. If you claim that some of the performance evaluation information being transmitted is CBI, you must submit a complete file generated through the use of the EPA’s ERT or an alternate electronic file consistent with the XML schema listed on the EPA’s ERT Web site, including information claimed to be CBI, on a compact disc, flash drive, or other commonly used electronic storage media to the EPA. The electronic storage media must be clearly marked as CBI and mailed to U.S. EPA/OAQPS/CORE CBI Office, Attention: Group Leader, Measurement Policy Group, MD C404-02, 4930 Old Page Rd., Durham, NC 27703. The same ERT or alternate file with the CBI omitted must be submitted to the EPA via the EPA’s CDX as described earlier in this paragraph. (2) For any performance evaluations of continuous monitoring systems measuring RATA pollutants that are not supported by the EPA’s ERT as listed on the EPA’s ERT Web site at the time of the test, you must submit the results of the performance evaluation to the Administrator at the appropriate address listed in § 63.13. (d) Excess emissions report. As required by §63.10(e)(3), the owner or operator shall submit a report (or a summary report) if measured emissions are in excess of the applicable standard. The report shall contain the information specified in87 §63.10(e)(3)(v) and be submitted semiannually unless quarterly reports are required as a result of excess emissions. (d) Reporting. In addition to the information required under § 63.10 of the General Provisions, the owner or operator must provide semiannual reports containing the information specified in paragraphs (d)(1) and (2) of this section to the Administrator or designated authority. (1) Excess emissions report. As required by § 63.10(e)(3), the owner or operator must submit a report (or a summary report) if measured emissions are in excess of the applicable standard. The report must contain the information specified in § 63.10(e)(3)(v) and be submitted semiannually unless quarterly reports are required as a result of excess emissions. (2) If there was a malfunction during the reporting period, the owner or operator must submit a report that includes the number, duration and a brief description for each type of malfunction which occurred during the reporting period and which caused or may have caused any applicable emission limitation to be exceeded. The report must also include a description of actions taken by an owner or operator during a malfunction of an affected source to minimize emissions in accordance with §§ 63.843(f) and 63.844(f), including actions taken to correct a malfunction.88 (e) Recordkeeping. The owner or operator shall maintain files of all information (including all reports and notifications) required by §63.10(b) and by this subpart. (1) The owner or operator must retain each record for at least 5 years following the date of each occurrence, measurement, maintenance, corrective action, report, or record. The most recent 2 years of records must be retained at the facility. The remaining 3 years of records may be retained offsite; (2) The owner or operator may retain records on microfilm, on a computer, on computer disks, on magnetic tape, or on microfiche; (3) The owner or operator may report required information on paper or on a labeled computer disc using commonly available and compatible computer software; and (4) In addition to the general records required by §63.10(b), the owner or operator shall maintain records of the following information: (i) Daily production rate of aluminum; (ii) Daily production rate of green anode material placed in the anode bake furnace; (iii) A copy of the startup, shutdown, and malfunction plan;[Reserved]89 (iv) Records of design information for paste production plant capture systems; (v) Records of design information for an alternative emission control device for a paste production plant; (vi) Records supporting the monitoring of similar potlines demonstrating that the performance of similar potlines is the same as or better than that of potlines sampled by manual methods; (vii) Records supporting a request for reduced sampling of potlines; (viii) Records supporting the correlation of emissions measured by a continuous emission monitoring system to emissions measured by manual methods and the derivation of the alternative emission limit derived from the measurements; (ix) The current implementation plan for emission averaging and any subsequent amendments; (x) Records, such as a checklist or the equivalent, demonstrating that the daily inspection of a potline with wet roof scrubbers for secondary emission control has been performed as required in §63.848(f)(5)(ii), including the results of each inspection; (xi) Records, such as a checklist or the equivalent, demonstrating that the daily visual inspection of the exhaust90 stack for each control device has been performed as required in §63.848(g), including the results of each inspection; (xii) For a potline equipped with an HF continuous emission monitor, records of information and data required by §63.10(c); (xiii) Records documenting the corrective actions taken when the limit(s) for an operating parameter established under §63.847(h) were exceeded, when visible emissions indicating abnormal operation were observed from a control device stack during a daily inspection required under §63.848(g), or when a problem was detected during the daily inspection of a wet roof scrubber for potline secondary control required in §63.848(f)(5)(ii); (xiv) Records documenting any POM data that are invalidated due to the installation and startup of a cathode; and (xv) Records documenting the portion of TF that is measured as particulate matter and the portion that is measured as gaseous when the particulate and gaseous fractions are quantified separately using an approved test method .; (xvi) Records of the occurrence and duration of each malfunction of operation (i.e., process equipment) or the air pollution control equipment and monitoring equipment; and (xvii) Records of actions taken during periods of malfunction to minimize emissions in accordance with §§ 63.843(f) and 63.844(f), including corrective actions to91 restore malfunctioning process and air pollution control and monitoring equipment to its normal or usual manner of operation. (f) All reports required by this subpart not subject to the requirements in paragraph (b) or (c) of this section must be sent to the Administrator at the appropriate address listed in § 63.13. If acceptable to both the Administrator and the owner or operator of a source, these reports may be submitted on electronic media. The Administrator retains the right to require submittal of reports subject to paragraph (b) of this section in paper format. **§ 63.851 Regulatory authority review procedures.** (a) The applicable regulatory authority shall notify the owner or operator in writing of the need for additional time to review the submissions in paragraphs (a)(1) through (a)(5) of this section or of approval or intent to deny approval of the submissions in paragraphs (a)(1) through (a)(5) of this section within 60 calendar days after receipt of sufficient information to evaluate the submission. The 60-day period begins after the owner or operator has been notified that the submission is complete. (1) The test plan in §63.847(b); (2) Request to change limits for operating parameters in §63.847(h)(3);92 (3) Request for similar potline monitoring in §63.848(d)(5); (4) Request for reduced sampling frequency in §63.848(e); and (5) Request for an alternative method in §63.849(e)(2). (b) The applicable regulatory authority shall notify the owner or operator in writing whether the submission is complete within 30 calendar days of receipt of the original submission or within 30 days of receipt of any supplementary information that is submitted. When a submission is incomplete, the applicable regulatory authority shall specify the information needed to complete the submission and shall give the owner or operator 30 calendar days after receipt of the notification to provide the information. **§ 63.852 Applicability of general provisions.** The requirements of the general provisions in subpart A of this part that are not applicable to the owner or operator subject to the requirements of this subpart are shown in appendix A of this subpart. **§ 63.853 Implementation and enforcement.** (a) This subpart can be implemented and enforced by the U.S. EPA, or a delegated authority such as the applicable State, local, or Tribal agency. If the U.S. EPA Administrator has delegated authority to a State, local, or Tribal agency, then93 that agency, in addition to the U.S. EPA, has the authority to implement and enforce this regulation. Contact the applicable U.S. EPA Regional Office to find out if this subpart is delegated to a State, local, or Tribal agency. (b) In delegating implementation and enforcement authority of this subpart to a State, local, or Tribal agency under subpart E of this part, the authorities contained in paragraph (c) of this section are retained by the Administrator of U.S. EPA and cannot be transferred to the State, local, or Tribal
agency. (c) The authorities that cannot be delegated to State, local, or Tribal agencies are as specified in paragraphs (c)(1) through (4) of this section. (1) Approval of alternatives to the requirements in §§63.840, 63.843 (with the exception of 63.843(b)(3)), 63.844, 63.845(a) introductory text, (a)(1), (b) through (e), (h), 63.846(a) through (c), and 63.847(a)(1) and (4). (2) Approval of major alternatives to test methods under §63.7(e)(2)(ii) and (f), as defined in §63.90, and as required in this subpart. (3) Approval of major alternatives to monitoring under §63.8(f), as defined in §63.90, and as required in this subpart.94 (4) Approval of major alternatives to recordkeeping and reporting under §63.10(f), as defined in §63.90, and as required in this subpart. **§ 63.854 Work Practice Standards for Potlines.** (a) Periods of operation other than startup. If you own or operate a new or existing primary aluminum reduction affected source, you must comply with the requirements of paragraphs (a)(1) through (4) of this section during periods of operation other than startup. (1) Ensure the potline scrubbers and exhaust fans are operational at all times. (2) Ensure that the primary capture and control system is operating at all times. (3) Hood covers should be replaced as soon as possible after each potroom operation. (4) Inspect potlines daily and perform the work practices specified in paragraphs (a)(4)(i) through (iii) of this section. (i) Identify unstable pots as soon as practicable but in no case more than 12 hours from the time the pot became unstable; (ii) Reduce cell temperatures to as low as practicable, and follow the written operating plan described in paragraph (b)(4) of this section if the cell temperature exceeds the specified high temperature limit; and95 (iii) Reseal pot crusts that have been broken as often and as soon as practicable. (5) Ensure that hood covers fit properly and are in good condition. (6) If the exhaust system is equipped with an adjustable damper system, the hood exhaust rate for individual pots must be increased whenever hood covers are removed from a pot, provided that the exhaust system will not be overloaded by placing too many pots on high exhaust. (7) Dust entrainment must be minimized during material handling operations and sweeping of the working aisles. (8) Only tapping crucibles with functional aspirator air return systems (for returning gases under the collection hooding) can be used, unless the regulatory authority approves an alternative tapping crucible. (b) Periods of startup. If you own or operate a new or existing primary aluminum reduction affected source, you must comply with the requirements of paragraphs (a)(1) through (4) and (b)(1) through (4) of this section during periods of startup for each affected potline. (1) Develop a potline startup schedule before starting up the potline. (2) Keep records of the number of pots started each day.96 (3) Inspect potlines daily and adjust pot parameters to their optimum levels, as specified in the operating plan described in paragraph (b)(4) of this section, including, but not limited to: alumina addition rate, exhaust air flow rate, cell voltage, feeding level, anode current and liquid and solid bath levels. (4) Prepare a written operating plan to minimize emissions during startup to include, but not limited to, the requirements in (b)(1) through (3) of this section. The operating plan must include a specified high temperature limit for pots that will trigger corrective action. **§ 63.855 Alternative Emissions Limits for Co-controlled New and Existing Anode Bake Furnaces.**  (a) Applicability. The owner or operator of a new anode bake furnace meeting the criteria of paragraphs (a)(1) and (2) of this section may demonstrate compliance with alternative TF and POM emission limits according to the procedures of this section. (1) The new anode bake furnace must have been permitted to operate prior to May 1, 1998; and (2) The new anode bake furnace must share a common control device with one or more existing anode bake furnaces.97 (b) TF emission limit. (1) Prior to the date on which each TF emission test is required to be conducted, the owner or operator must determine the applicable TF emission limit using Equation 6-A, 

###    

###     N E N E TFE TFC P P P P L L      / 018

. 0 Eq. 6-A

Where:
L TFC = Combined emission limit for TF, lb/ton green anode material placed in the bake furnace;
L TFE = TF limit for emission averaging for the total number of new and existing anode bake furnaces from Table 4 to this subpart;
P E = Mass of green anode placed in existing anode bake furnaces in the twelve months preceding the compliance test, ton/year; and
P N = Mass of green anode placed in new anode bake furnaces in the twelve months preceding the compliance test, ton/year. (2) The owner or operator of a new anode bake furnace that is controlled by a control device that also controls emissions of TF from one or more existing anode bake furnaces must not discharge, or cause to be discharged into the atmosphere, any emissions of TF in excess of the emission limits established in paragraph (b)(1) of this section. (c) POM emission limits. (1) Prior to the date on which each POM emission test is required to be conducted, the owner or98 operator must determine the applicable POM emission limit using Equation 6-B, 

###    

###     N E N E POMC P P P P L      / 045

. 0 17

. 0 Eq. 6-B

Where:
L POMC = Combined emission limit for POM, lb/ton green anode material placed in the bake furnace. (2) The owner or operator of a new anode bake furnace that is controlled by a control device that also controls emissions of POM from one or more existing anode bake furnaces must not discharge, or cause to be discharged into the atmosphere, any emissions of TF in excess of the emission limits established in paragraph (c)(1) of this section. **§§ 63.85 4**  **-63.859 [Reserved] Table 1 to Subpart LL of Part 63—Potline TF Limits for Emission**  **Averaging**

**Type Monthly TF limit (1b/ton)**  **[for given number of potlines]**
**2 lines 3 lines**  **4 lines 5**  **lines 6**  **lines 7**  **lines 8 lines** 

CWPB1 1.7 1.6 1.5 1.5 1.4 1.4 1.4

CWPB2 2.9 2.8 2.7 2.7 2.6 2.6 2.6

CWPB3 2.3 2.2 2.2 2.1 2.1 2.1 2.1

VSS1 2 1.9 1.8 1.7 1.7 1.7 1.799 VSS2 2.6 2.5 2.5 2.4 2.4 2.4 2.4

HSS 2.5 2.4 2.4 2.3 2.3 2.3 2.3

SWPB 1.4 1.3 1.3 1.2 1.2 1.2 1.2

**Table 2 to Subpart LL of Part 63—Potline POM Limits for Emission Averaging** 

**Type Quarterly POM limit (lb/ton)**  **[for given number of potlines]**

**2 lines 3 lines**  **4 lines 5 lines**  **6 lines 7 lines**  **8 line** 

**s Table 1 to Subpart LL of Part 63—**  **P otline TF Limits**  **for Emission Averaging**

**Type Semiannual TF limit (lb/ton)**  **[for given number of potlines]**
**2 lines**  **3 lines**  **4 lines**  **5 lines**  **6 lines**  **7 lines**  **8 lines**  CWPB1 1.7 1.6 1.5 1.5 1.4 1.4 1.4 CWPB2 2.9 2.8 2.7 2.7 2.6 2.6 2.6 CWPB3 2.3 2.2 2.2 2.1 2.1 2.1 2.1
SWPB 1.4 1.3 1.3 1.2 1.2 1.2 1.2 VSS2 2.6 2.5 2.5 2.4 2.4 2.4 2.4100 HSS 4.1 3.8 3.7 3.5 3.5 3.4 3.3

VSS1 2.1 2.0 1.9 1.9 1.8 1.8 1.8

VSS2 5.0 4.7 4.5 4.4 4.3 4.2 4.1 **Table 2 to Subpart LL of Part 63— P**  **otl i**  **ne POM Limits for Emission Averaging** 

**Type Semiannual POM limit (lb/ton)**  **[for given number of potlines]**
**2 line** 

**s 3 lines**  **4 line** 

**s 5**  **lines 6**  **line**

**s 7 lines**  **8 line** 

**s** CWPB1 1 0.9 0.9 0.9 0.8 0.8 0.8 CWPB2 11.6 11.2 10.8 10.8 10.4 10.4 10.4 CWPB3 2.5 2.4 2.4 2.3 2.3 2.3 2.3
SWPB 14.8 13.8 13.8 13.8 13.8 13.8 13.8 VSS2 1.7 1.6 1.5 1.5 1.4 1.4 1.4

**Table 3 to Subpart LL of Part 63—Anode Bake Furnace Limits for Emission Averaging** 

**Number of furnaces E**  **mission limit (lb/ton of anode)**

**T F**  **POM**

2 0.11 0.17101 3 0.090 0.17

4 0.077 0.17

5 0.070 0.17 **Table 3 to Subpart LL of Part 63— P**  **otline PM Limits for Emission Averaging** 

**Type Semiannual PM limit (lb/ton)**  **[for given number of potlines]**

**2 lines**  **3 lines**  **4 line** 

**s 5 lines**  **6 lines 7**  **line**

**s 8 lines** 

CWPB1 6.1 6.1 5.3 5.3 5.0 5.0 5.0 CWPB2 10.6 10.3 9.9 9.9 9.5 9.5 9.5 CWPB3 18.4 17.6 17.6 16.8 16.8 16.8 16.8
SWPB 4.3 3.9 3.9 3.7 3.7 3.7 3.7 VSS2 25 24.1 24.1 23.1 23.1 23.1 23.1

**Table 4 to Subpart LL of Part 63—Anode Bake Furnace Limits for Emission Averaging**  **Number of furnaces**  **Emission limit (lb/ton of anode)**
**TF P**  **OM P**  **M** 2 0.11 0.17 0.11102 3 0.09 0.17 0.091 4 0.077 0.17 0.076 5 0.07 0.17 0.071

**Appendix A to Subpart LL of Part 63—Applicability of General Provisions** 

**General provisions**  **citation Requirement**  **App l**  **ies to subpart LL**  **Comment** 63.1(c)(2) No All are major sources.

63.2 Definition of “reconstruction” No Subpart LL defines “reconstruction.”

63.6(c)(1) Compliance date for existing

sources No Subpart LL specifies compliance date for existing sources.

63.6(h) Opacity/VE standards Only in §63.845 Opacity standards applicable only when i ncorporating the NSPS requirements under §63.845.103 63.7(a)(2)(ii) and (iii) Performance testing requirements No Subpart LL specifies performance test dates. 63.8(c)(4)–(c)(8) CMS operation and maintenance No Subpart LL does not require COMS/CMS or CMS performance specifications. 63.8(d) Quality control No Subpart LL does not require CMS or CMS performance evaluation. 63.8(e) Performance evaluation for CMS No

63.9(b)(1)–(5) Initial notifications Yes, except as noted in “comment” column § 63.850(a)(9) includes requirement for

s tartup of an existing affected source that has been shut down. 63.9(e) Notification of performance
test No Subpart LL specifies notification of performance tests.104 63.9(f) Notification of VE or opacity test Only in §63.845 Notification is required only when i ncorporating the NSPS requirements under §63.845. 63.9(g) Additional CMS notification No

63.10(d)(2) Performance test reports No Subpart LL specifies performance test reporting. 63.10(d)(3) Reporting VE/opacity observations Only in §63.845 Reporting is required only when i ncorporating the NSPS requirements under §63.845. 63.10(e)(2) Reporting performance evaluations No Subpart LL does not require performance evaluation for CMS. 63.11(a)–(b) Control device requirements No Flares not applicable.

**Appendix A to Subpart LL of Part 63—Applicability of General Provisions (40 CFR Part 63, Subpart A)** 105 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.1 (a)(1) through (4) General Applicability Yes

63.1 (a)(5) No [Reserved]. 63.1(a)(6) Yes 63.1(a)(7) through (9) No [Reserved].

63.1(a)(10) through (12) Yes

63.1(b)(1) through (3) Initial Applicability Determination Yes (b)(2) Reserved.

63.1(c)(1) Applicability after standard Established Yes

63.1(c)(2) Yes Area sources are not subject to this subpart. 63.1(c)(3) and (4) No [Reserved].

63.1(c)(5) Yes106 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.1(d) No [Reserved]. 63.1(e) Applicability of Permit Program Yes

63.2 Definitions Yes Reconstruction defined in § 63.842. 63.3 Units and Abbreviations Yes

63.4(a)(1) and (2) Prohibited activities Yes

63.4(a)(3) through (5) No [Reserved].

63.4(b) and (c) Circumvention/S everability Yes

63.5(a) Construction/Re construction Applicability Yes107 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.5(b)(1) Existing, New, Reconstructed Sources Requirements Yes

63.5(b)(2) No [Reserved]. 63.5(b)(3) and (4) Yes

63.5(b)(5) No [Reserved]. 63.5(b)(6) Yes 63.5(c) No [Reserved]. 63.5(d) Application for Approval of Construction/Re construction Yes

63.5(e) Approval of Construction/Re construction Yes108 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.5(f) Approval of Construction/Re construction Based on State Review Yes

63.6(a) Compliance with Standards and Maintenance Applicability Yes

63.6(b)(1) through (5) New and Reconstructed Source Dates Yes See § 847(a)(6) and (7)

63.6(b)(6) No [Reserved]. 63.6(b)(7) Yes 63.6(c)(1) Existing Source
Dates No See § 847(a)

63.6(c)(2) Yes 63.6(c)(3) and (4) No [Reserved].

63.6(c)(5) Yes 63.6(d) No [Reserved].109 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.6(e)(1)(i) No See §§ 63.843(f) and 63.844(f) for general duty requirement. 63.6(e)(1)(ii) No 63.6(e)(1)(iii) Yes 63.6(e)(2) No [Reserved]. 63.6(e)(3) Startup, Shutdown and Malfunction Plan No

63.6(f)(1) Compliance with Emissions Standards No

63.6(f) (2) Methods/Finding of Compliance Yes

63.6(g) Alternative Standard Yes110 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.6(h) Compliance with Opacity/VE Standards Only in § 63.845 Opacity standards applicable only when incorporating the NSPS requirements under § 63.845 63.6(i)(1) through (14) Extension of Compliance Yes

63.6(i)(15) No [Reserved]. 63.6(i)(16) Yes 63.6(j) Exemption from Compliance Yes

63.7(a) Performance
Test Requirements Applicability Yes

63.7(b) Notification Yes 63.7(c) Quality Assurance/Test Plan Yes111 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.7(d) Testing facilities Yes

63.7(e)(1) Conduct of
Tests No See § 63.847(d)

63.7(e)(2) through (4) Yes

63.7(f),(g), (h) Alternative Test Method Yes

63.8(a)(1) and (2) Monitoring Requirements Applicability Yes

63.8(a)(3) No [Reserved]. 63.8(b) Conduct of Monitoring Yes

63.8(c)(1)(i) No See §§ 63.843(f) and 63.844(f) for general duty requirement. 63.8(c)(1)(ii) Yes 63.8(c)(1)(iii) No112 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.8(c)(2) through (d)(2) Yes

63.8(d)(3) Yes, except for last
sentence 63.8(e) through (g) Yes

63.9(a) Notification Requirements Applicability Yes

63.9(b) Initial Notifications Yes Notification of
re-start specified in § 63.850(a)(9) 63.9(c) Request for Compliance Extension Yes113 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.9(d) New Source Notification for Special Compliance Requirements Yes

63.9(e) Notification of Performance
Test No

63.9(f) Notification of VE/Opacity Test No

63.9(g) Additional CMS Notifications No

63.9(h)(1) through (3) Notification of Compliance Status Yes

63.9(h)(4) No [Reserved]. 63.9(h)(5) and (6) Yes

63.9(i) Adjustment of Deadlines Yes114 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.9(j) Change in Previous Information Yes

63.10(a) Recordkeeping/R eporting Applicability Yes

63.10(b)(1) General Recordkeeping Requirements Yes

63.10(b)(2)(i) No 63.10(b)(2)(ii) No See §§ 63.850(e)(4)(x vi) and (xvii) for recordkeeping of occurrence and duration of malfunctions and recordkeeping of actions taken during malfunction.115 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.10(b)(2)(iii ) Yes

63.10(b)(2)(iv) and (v) No

63.10(b)(2)(vi) through (xiv) Yes

63.(10)(b)(3) Yes 63.10(c)(1) through (9) Yes

63.10(c)(10) and (11) No See §§ 63.850(e)(4)(x vi) and (xvii)for recordkeeping of malfunctions. 63.10(c)(12) through (14) Yes

63.10(c)(15) No 63.10(d)(1) General Reporting Requirements Yes

63.10(d)(2) No See § 63.850(b)116 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.10(d)(3) and (4) Yes

63.10(d)(5) StartupShutdown and Malfunction Reports No See § 63.850(d)(2) for reporting of malfunctions. 63.10(e) and (f) Additional CMS Reports and Recordkeeping/ Reporting Waiver Yes

63.11 Control Device/work practices requirements Applicability No

63.12 State Authority and Delegations Yes

63.13 Addresses Yes 63.14 Incorporation by Reference Yes117 **Reference Section(s) ...**  **Requirement Applies to**  **subpart LL Comment** 

63.15 Information Availability /Confidentialit
y Yes

63.16 Performance Track Provisions No