Primary aluminum reduction plants

Primary aluminum reduction plants. (1) Applicability and designation of affected facility. (a) The affected facilities in primary aluminum reduction plants to which this section applies are potroom groups and anode bake plants. (b) Except as provided in par. (c) , any affected facility under par. (a) that commences construction or modification after October 23, 1974, is subject to the requirements of this section. (c) An owner or operator of an affected facility under par. (a) may elect to comply with the requirements of this section or the requirements of 40 CFR part 63 . (2) Definitions. As used in this section, terms not defined in this subsection have the meanings given in s. NR 440.02 . (a) “Aluminum equivalent” means an amount of aluminum which can be produced from a Mg of anodes produced by an anode bake plant as determined by sub. (6) (b) 4. b. (b) “Anode bake plant” means a facility which produces carbon anodes for use in a primary aluminum reduction plant. (c) “Potroom” means a building unit which houses a group of electrolytic cells in which aluminum is produced. (d) “Potroom group” means an uncontrolled potroom, a potroom which is controlled individually, or a group of potrooms or potroom segments ducted to a common control system. (e) “Primary aluminum reduction plant” means any facility manufacturing aluminum by electrolytic reduction. (f) “Primary control system” means an air pollution control system designed to remove gaseous and particulate fluorides from exhaust gases which are captured at the cell. (g) “Roof monitor” means that portion of the roof of a potroom where gases not captured at the cell exit from the potroom. (h) “Total fluorides” means elemental fluorine and all fluoride compounds as measured by reference methods specified in sub. (6) or by equivalent or alternative methods. (3) Standards for fluorides. (a) On and after the date on which the initial performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any affected facility any gases containing total fluorides, as measured according to sub. (6) , in excess of: 1. 1.0 kg/Mg (2.0 lb/ton) of aluminum produced for potroom groups at Soderberg plants, except that emissions between 1.0 kg/Mg and 1.3 kg/Mg (2.6 lb/ton) shall 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 affected facility during the performance tests; 2. 0.95 kg/Mg (1.9 lb/ton) of aluminum produced for potroom groups at prebake plants, except that emissions between 0.95 kg/Mg and 1.25 kg/Mg (2.5 lb/ton) shall 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 affected facility during the performance test; and 3. 0.050 kg/Mg (0.10 lb/ton) of aluminum equivalent for anode bake plants. (b) Within 30 days of any performance test which reveals emissions which fall between the 1.0 kg/Mg and 1.3 kg/Mg levels in par. (a) 1. or between to 0.95 kg/Mg and 1.25 kg/Mg levels in par. (a) 2. , the owner or operator shall submit a report to the department indicating whether all necessary control devices were on-line and operating properly during the performance test, describing the operating and maintenance procedures followed, and setting forth any explanation for the excess emissions. (4) Standard for visible emissions. (a) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere: 1. From any potroom group any gases which exhibit 10% opacity or greater, or 2. From any anode bake plant any gases which exhibit 20% opacity or greater. (5) Monitoring of operations. (a) The owner or operator of any affected facility subject to the provisions of this section shall install, calibrate, maintain and operate monitoring devices which can be used to determine daily the weight of aluminum and anode produced. The weighing devices shall have an accuracy of ± 5% over their operating range. (b) The owner or operator of any affected facility shall maintain a record of daily production rates of aluminum and anodes, raw material feed rates, and cell or potline voltages. (c) Following the initial performance test as required under s. NR 440.08 (1) , an owner or operator shall conduct a performance test at least once each month during the life of the affected facility, except when malfunctions prevent representative sampling, as provided under s. NR 440.08 (3) . The owner or operator shall give the department at least 15 days advance notice of each test. The department may require additional testing under ch. NR 439 . (6) Test methods and procedures. (a) In conducting the performance tests required in s. NR 440.08 , the owner or operator shall use as reference methods and procedures the test methods in Appendix A of 40 CFR part 60 , incorporated by reference in s. NR 440.17 , or other methods and procedures as specified in this subsection, except as provided in s. NR 440.08 (2) . (b) The owner or operator shall determine compliance with the total fluorides and visible emission standards in subs. (3) and (4) as follows: 1. The emission rate (E p ) of total fluorides from potroom groups shall be computed for each run using the following equation: 2. The emission rate (E b ) of total fluorides from anode bake plants shall be computed for each run using the following equation: 3. Method 13A or 13B shall be used for ducts or stacks and Method 14 for roof monitors not employing stacks or pollutant collection systems, to determine the total fluorides concentration (C s ) and volumetric flow rate (Q sd ) of the effluent gas. The sampling time and sample volume for each run shall be at least 8 hours and 6.80 dscm (240 dscf) for potroom groups and at least 4 hours and 3.40 dscm (120 dscf) for anode bake plants. 4. The monitoring devices of sub. (5) (a) shall be used to determine the daily weight of aluminum and anode produced. a. The aluminum production rate (P) shall be determined by dividing 720 hours into the weight of aluminum tapped from the affected facility during a period of 30 days before and including the final run of a performance test. b. The aluminum equivalent production rate (P e ) for anodes shall be determined as 2 times the average weight of anode produced during a representative oven cycle divided by the cycle time. An owner or operator may establish a multiplication factor other than 2 by submitting production records of the amount of aluminum produced and the concurrent weight of anodes consumed by the potrooms. 5. Method 9 and the procedures in s. NR 440.11 shall be used to determine opacity.