(a) Source applicability. The requirements specified in this section apply to every entity which engages in any of the following activities:

(1) Use of a controlled substance as a process agent.

(2) [Reserved]

(b) Emissions of controlled substances to report. Every entity that engages in any activity listed in paragraph (a) of this section must report, for each applicable facility, emissions of the controlled substances in paragraph (b)(1) of this section from the processes listed in paragraph (b)(2) of this section.

(1) Emissions of controlled substances. For purposes of reporting emissions under this section, the term “controlled substance” applies to the following controlled substances:

(i) Each controlled substance used as a process agent.

(ii) [Reserved]

(2) Processes. For purposes of this section, the term “process” applies to the following activities:

(i) Each activity listed in paragraph (a) of this section;

(ii) Each separation process for the reuse or recycling of the controlled substance;

(iii) Each transformation process of the controlled substance, where the controlled substance is produced at the facility and used in processes resulting in its transformation at the same facility;

(iv) Each transformation process of the controlled substance at the facility, where one or more of the controlled substances transformed at the facility is produced at another facility; and

(v) Each destruction process of the controlled substance.

(c) Calculating emissions for controlled substances. For every activity listed in paragraph (a) of this section, each entity must calculate emissions of the controlled substances from each process using the emission factor, emission calculation factor, or mass balance method specified in paragraphs (c)(1) through (4) of this section, as appropriate. The mass balance method may only be used for batch operations without on-site production or transformation of controlled substances. For destruction processes that destroy controlled substances, the entity must calculate emissions using the procedures in paragraph (c)(4) of this section.

(1) Emission factor and emission calculation factor methods. To use the method in this paragraph (c)(1) for batch processes, each entity must use the methods in either paragraph (c)(1)(iii) (Emission Factor approach) or (iv) (Emission Calculation Factor approach) of this section. To use the method in this paragraph (c)(1) for continuous processes, the entity must first make a preliminary estimate of the emissions from each individual continuous process vent under paragraph (c)(1)(i) of this section. If the entity's continuous process operates under different conditions as part of normal operations, that entity must also define the different operating scenarios and make a preliminary estimate of the emissions from the vent for each operating scenario. Then, compare the preliminary estimate for each continuous process vent (summed across operating scenarios) to the criteria in paragraph (c)(1)(ii) of this section to determine whether the process vent meets the criteria for using the emission factor method described in paragraph (c)(1)(iii) of this section or whether the process vent meets the criteria for using the emission calculation factor method described in paragraph (c)(1)(iv) of this section. For continuous process vents that meet the criteria for using the emission factor method described in paragraph (c)(1)(iii) of this section and that have more than one operating scenario, compare the preliminary estimate for each operating scenario to the criteria in paragraph (c)(1)(iii)(B) of this section to determine whether an emission factor must be developed for that operating scenario.

(i) Preliminary estimate of emissions by process vent. Each entity must estimate the annual emissions of the controlled substance for each process vent within each operating scenario of a continuous process using the approaches specified in paragraph (c)(1)(i)(A) or (B) of this section, accounting for any destruction as specified in paragraph (c)(1)(i)(C) of this section. The entity must determine emissions of controlled substances by process vent by using measurements, by using calculations based on chemical engineering principles and chemical property data, or by conducting an engineering assessment. The entity may use previously conducted measurements, calculations, or assessments if they represent current process operating conditions or process operating conditions that would result in higher controlled substance emissions than the current operating conditions and if they were performed in accordance with paragraph (c)(1)(i)(A), (B), or (C) of this section, as applicable. The entity must document all data, assumptions, and procedures used in the calculations or engineering assessment and keep a record of the emissions determination as required by paragraph (f)(1) of this section.

(A) Engineering calculations. For process vent emission calculations, each entity may use any of paragraph (c)(1)(i)(A)(1), (2), or (3) of this section.

(1) U.S. Environmental Protection Agency, Emission Inventory Improvement Program, Volume II: Chapter 16, Methods for Estimating Air Emissions from Chemical Manufacturing Facilities, August 2007, Final (incorporated by reference, see § 82.27).

(2) Each entity may determine the controlled substance emissions from any process vent within the process using the procedures specified in § 63.1257(d)(2)(i) and (d)(3)(i)(B) of this chapter, except as specified in paragraphs (c)(1)(i)(A)(2)(i) through (iv) of this section. For the purposes of this section, use of the term “HAP” in § 63.1257(d)(2)(i) and (d)(3)(i)(B) of this chapter means “controlled substance.”

(i) To calculate emissions caused by the heating of a vessel without a process condenser to a temperature lower than the boiling point, each entity must use the procedures in § 63.1257(d)(2)(i)(C)(3) of this chapter.

(ii) To calculate emissions from depressurization of a vessel without a process condenser, each entity must use the procedures in § 63.1257(d)(2)(i)(D)(10) of this chapter.

(iii) To calculate emissions from vacuum systems, the terms used in equation 33 to § 63.1257(d)(2)(i)(E) of this chapter are defined as follows. Psystem means the absolute pressure of the receiving vessel. P i means the partial pressure of the controlled substance determined at the exit temperature and exit pressure conditions of the condenser or at the conditions of the dedicated receiver. Pj means the partial pressure of condensables (including controlled substances) determined at the exit temperature and exit pressure conditions of the condenser or at the conditions of the dedicated receiver. MWcontrolled substance means the molecular weight of the controlled substance determined at the exit temperature and exit pressure conditions of the condenser or at the conditions of the dedicated receiver.

(iv) To calculate emissions when a vessel is equipped with a process condenser or a control condenser, each entity must use the procedures in § 63.1257(d)(3)(i)(B) of this chapter, except as follows. Each entity must determine the flow rate of gas (or volume of gas), partial pressures of condensables, temperature (T), and controlled substance molecular weight (MWcontrolled substance) at the exit temperature and exit pressure conditions of the condenser or at the conditions of the dedicated receiver. Each entity must assume that all of the components contained in the condenser exit vent stream are in equilibrium with the same components in the exit condensate stream (except for noncondensables). Each entity must perform a material balance for each component, if the condensate receiver composition is not known. For the emissions from purging, the term for time, t, must be used in equation 12 to § 63.1257(d)(2)(i)(B) of this chapter. Emissions from empty vessel purging must be calculated using equation 36 to § 63.1257(d)(2)(i)(H) of this chapter and the exit temperature and exit pressure conditions of the condenser or the conditions of the dedicated receiver.

(3) Commercial software products that follow chemical engineering principles (e.g., including the calculation methodologies in paragraphs (c)(1)(i)(A)(1) and (2) of this section).

(B) Engineering assessments. For process vent emissions determinations, each entity may conduct an engineering assessment to calculate uncontrolled emissions. An engineering assessment includes, but is not limited to, the following:

(1) Previous test results, provided the tests are representative of current operating practices of the process.

(2) Bench-scale or pilot-scale test data representative of the process operating conditions.

(3) Maximum flow rate, controlled substance emission rate, concentration, or other relevant parameters specified or implied within a permit limit applicable to the process vent.

(4) Design analysis based on chemical engineering principles, measurable process parameters, or physical or chemical laws or properties.

(C) Impact of destruction for the preliminary estimate. If the process vent is vented to a destruction unit, each entity may reflect the impact of the destruction unit on emissions. In the emissions estimate, account for the following:

(1) The demonstrated destruction efficiencies of the device for the controlled substance in the vent stream for periods when the destruction device is in use.

(2) Any periods when the process vent is not vented to the destruction unit.

(D) Use of typical recent values. In the calculations in paragraphs (c)(1)(i)(A) through (C) of this section, the values used for the expected process activity and for the expected fraction of that activity, whose emissions will be vented to the properly functioning destruction unit, must be based on either typical recent values for the process or values that overestimate emissions from the process, unless there is a compelling reason to adopt a different value (e.g., installation of a destruction unit for a previously uncontrolled process). If there is such a reason, it must be documented in the monitoring plan.

(ii) Method selection for continuous process vents. (A) Based on the calculations under paragraph (c)(1)(i) of this section, as well as any subsequent measurements and calculations under this section, rank the process vents based on controlled substance emissions, upstream of any destruction unit, summed across all operating scenarios, from largest to smallest estimated annual emissions of controlled substances. The continuous process vents that comprise the top quartile of estimated annual emissions of controlled substances must use the method in paragraph (c)(1)(iii) of this section (Emission Factor approach). The process vent emissions will be based on the past 3 years for the ranking analysis.

(B) The remaining continuous process vents that comprise the bottom three quartiles of estimated annual emissions of controlled substances may use either the emission factor method specified in paragraph (c)(1)(iii) of this section (Emission Factor approach) or a method specified in paragraph (c)(1)(iv) of this section (Emission Calculation Factor approach).

(1) Each entity must conduct emission testing for process-vent-specific emission factor development upstream of the destruction unit.

(2) The emission testing for process-vent-specific emission factor development may be conducted on the outlet side of a wet scrubber in place for acid gas reduction, if there is no appreciable reduction in the controlled substance by the wet scrubber.

(iii) Process-vent-specific emission factor method. For each process vent, each entity must conduct an emission test according to the procedures in paragraph (d) of this section and measure the process activity, such as the feed rate, production rate, or other process activity rate, during the test as described in this paragraph (c)(1)(iii). All emissions test data and procedures used in developing emission factors must be documented according to paragraph (f) of this section. If more than one operating scenario applies to the process that contains the subject process vent, each entity must use the method in either paragraph (c)(1)(iii)(A) or (B) of this section.

(A) Conduct a separate emissions test for operation under each operating scenario.

(B) Conduct an emissions test for the operating scenario that is expected to have the largest emissions of controlled substances (considering both activity levels and emission calculation factors) on an annual basis. Also conduct an emissions test for each additional operating scenario for which the emission calculation factor differs by 15 percent or more from the emission calculation factor of the operating scenario that is expected to have the largest emissions(or of another operating scenario for which emission testing is performed), unless the difference between the operating scenarios is solely due to the application of a destruction unit to emissions under one of the operating scenarios. For any other operating scenarios, adjust the process-vent specific emission factor developed for the operating scenario that is expected to have the largest emissions (or for another operating scenario for which emission testing is performed) using the approach in paragraph (c)(1)(iii)(G) of this section.

(C) Each entity must measure the process activity, such as the process feed rate, process production rate, or other process activity rate, as applicable, during the emissions test and calculate the rate for the test period, in kg (or another appropriate metric) per hour.

(D) For continuous processes, each entity must calculate the hourly emission rate of each controlled substance using equation 1 to this paragraph (c)(1)(iii)(D) and determine the hourly emission rate of each controlled substance per process vent (and per operating scenario, as applicable) for the test run.

Equation 1 to Paragraph (c)(1)(iii)(D) Where: EContPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, during the emission test during test run r (kg/hr). CPV = Concentration of controlled substance p during test run r of the emission test (ppmv). MW = Molecular weight of controlled substance p (g/g-mole). QPV = Flow rate of the process vent stream during test run r of the emission test (m3/min). SV = Standard molar volume of gas (0.0240 m 3/g-mole at 68 °F and 1 atm). 1/10 3 = Conversion factor (1 kilogram/1,000 grams). 60/1 = Conversion factor (60 minutes/1 hour).

(E) Each entity must calculate a site-specific, process-vent-specific emission factor for each controlled substance for each process vent and each operating scenario, in kg of controlled substance per process activity rate (e.g., kg of feed or production), as applicable, using equation 2 to this paragraph (c)(1)(iii)(E). For continuous processes, divide the hourly controlled substance emission rate during the test by the hourly process activity rate during the test runs.

Equation 2 to Paragraph (c)(1)(iii)(E) Where: EFPV = Emission factor for controlled substance p emitted from process vent v during process i, operating scenario j (e.g., kg emitted/kg activity). EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, during the emission test during test run r, for either continuous or batch (kg emitted/hr for continuous, kg emitted/batch for batch). ActivityEmissionTest = Process feed, process production, or other process activity rate for process i, operating scenario j, during the emission test during test run r (e.g., kg product/hr). r = Number of test runs performed during the emission test.

(F) If emissions testing is conducted upstream of the destruction unit, apply the destruction efficiencies of the device that have been demonstrated for the controlled substance in the vent stream to the controlled substance emissions for the process vent (and operating scenario, as applicable), using equation 3 to this paragraph (c)(1)(iii)(F). Each entity may apply the destruction efficiency only to the portion of the process activity during which emissions are vented to the properly functioning destruction unit (i.e., controlled).

Equation 3 to Paragraph (c)(1)(iii)(F) EPV = EFPV-U * (Activityu + Activityc * (1−DE)) Where: EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year, considering destruction efficiency (kg). EFPV-U = Emission factor (uncontrolled) for controlled substance p emitted from process vent v during process i, operating scenario j (kg emitted/kg product). ActivityU = Total process feed, process production, or other process activity for process i, operating scenario j, during the year for which the process vent is not vented to the properly functioning destruction unit (e.g., kg product). ActivityC = Total process feed, process production, or other process activity for process i, operating scenario j, during the year for which the process vent is vented to the properly functioning destruction unit (e.g., kg product). DE = Demonstrated destruction efficiency of the destruction unit (weight fraction).

(G) For process vents from processes with multiple operating scenarios, use equation 4 to this paragraph (c)(1)(iii)(G) to develop an adjusted process-vent-specific emission factor for each operating scenario whose emission calculation factor differs by less than 15 percent from the emission calculation factor of the operating scenario that is expected to have the largest emissions (or of another operating scenario for which emission testing is performed).

Equation 4 to Paragraph (c)(1)(iii)(G) Where: EFPVadj = Adjusted process-vent-specific emission factor for an untested operating scenario. ECFUT = Emission calculation factor for the untested operating scenario developed under paragraph (c)(4) of this section. ECFT = Emission calculation for the tested operating scenario developed under paragraph (c)(4) of this section. EFPV = Process vent specific emission factor for the tested operating scenario.

(H) Sum the emissions of each controlled substance from all process vents in each operating scenario and all operating scenarios in the process for the year to estimate the total process vent emissions of each controlled substance from the process, using equation 5 to this paragraph (c)(1)(iii)(H).

Equation 5 to Paragraph (c)(1)(iii)(H) Where: EPpi = Mass of controlled substance p emitted from process vents for process i for the year (kg). EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year, considering destruction efficiency (kg). v = Number of process vents in process i, operating scenario j. o = Number of operating scenarios for process i.

(iv) Process-vent-specific emission calculation factor method. For each process vent within an operating scenario, determine controlled substances emissions by calculations and determine the process activity rate, such as the feed rate, production rate, or other process activity rate, associated with the emission rate.

(A) Each entity must calculate uncontrolled emissions of controlled substances by individual process vent, EPV, by using measurements, by using calculations based on chemical engineering principles and chemical property data, or by conducting an engineering assessment. Use the procedures in paragraph (c)(1)(i)(A) or (B) of this section, except paragraph (c)(1)(i)(B)(3) of this section. The procedures in paragraphs (c)(1)(i)(A) and (B) of this section may be applied either to batch process vents or to continuous process vents. The uncontrolled emissions must be based on a typical batch or production rate under a defined operating scenario. The process activity rate associated with the uncontrolled emissions must be determined. The methods, data, and assumptions used to estimate emissions for each operating scenario must be selected to yield a best estimate (expected value) of emissions rather than an over- or underestimate of emissions for that operating scenario. All data, assumptions, and procedures used in the calculations or engineering assessment must be documented according to paragraph (f) of this section.

(B) Each entity must calculate a site-specific, process-vent-specific emission calculation factor for each process vent each operating scenario, and each controlled substance, in kg of controlled substance per activity rate (e.g., kg of feed or production) as applicable, using equation 6 to this paragraph (c)(1)(iv)(B).

Equation 6 to Paragraph (c)(1)(iv)(B) Where: ECFPV = Emission calculation factor for controlled substance p emitted from process vent v during process i, operating scenario j (e.g., kg emitted/kg product). EPV = Average mass of controlled substance p emitted, based on calculations, from process vent v from process i, operating scenario j, during the period or batch for which emissions were calculated, for either continuous or batch (kg emitted/hr for continuous, kg emitted/batch for batch). Activity Representative = Process feed, process production, or other process activity rate corresponding to average mass of emissions based on calculations (e.g., kg product/hr for continuous, kg product/batch for batch).

(C) Each entity must calculate emissions of each controlled substance for the process vent (and for each operating scenario, as applicable) for the year by multiplying the process-vent-specific emission calculation factor by the total process activity, as applicable, for the year, using equation 7 to this paragraph (c)(1)(iv)(C).

Equation 7 to Paragraph (c)(1)(iv)(C) EPV = ECFPV * Activity Where: EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year (kg). ECFPV = Emission calculation factor for controlled substance p emitted from process vent v during process i, operating scenario j (kg emitted/activity) (e.g., kg emitted/kg product). Activity = Process feed, process production, or other process activity for process i, operating scenario j, during the year.

(D) If the process vent is vented to a destruction unit, apply the demonstrated destruction efficiency of the device to the controlled substance emissions for the process vent (and operating scenario, as applicable), using equation 8 to this paragraph (c)(1)(iv)(D). Apply the destruction efficiency only to the portion of the process activity that is vented to the properly functioning destruction unit (i.e., controlled).

Equation 8 to Paragraph (c)(1)(iv)(D) EPV = ECFPV * (Activityu + Activityc * (1−DE)) Where: EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year considering destruction efficiency (kg). ECFPV = Emission calculation factor for controlled substance p emitted from process vent v during process i, operating scenario j (e.g., kg emitted/kg product). ActivityU = Total process feed, process production, or other process activity for process i, operating scenario j, during the year for which the process vent is not vented to the properly functioning destruction unit (e.g., kg product). ActivityC = Total process feed, process production, or other process activity for process i, operating scenario j, during the year for which the process vent is vented to the properly functioning destruction unit (e.g., kg product). DE = Demonstrated destruction efficiency of the destruction unit (weight fraction).

(E) Sum the emissions of each controlled substance from all process vents in each operating scenario and all operating scenarios in the process for the year to estimate the total process vent emissions of each controlled substance from the process, using equation 9 to this paragraph (c)(1)(iv)(E).

Equation 9 to Paragraph (c)(1)(iv)(E) Where: EPpi = Mass of controlled substance p emitted from process vents for process i for the year (kg). EPV = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year, considering destruction efficiency (kg). v = Number of process vents in process i, operating scenario j. o = Number of operating scenarios in process i.

(2) Calculate emissions for equipment leaks (EL). If activity is covered under paragraph (c)(1) of this section, each entity must calculate the emissions from pieces of equipment associated with processes covered under this section. If conducting monitoring of equipment in controlled substance service, monitoring must be conducted for those in light liquid and in gas and vapor service. If conducting monitoring of equipment in controlled substance service, the entity may exclude from monitoring each piece of equipment that is difficult-to-monitor, that is unsafe-to-monitor, that is insulated, or that is in heavy liquid service; the entity may exclude from monitoring each pump with dual mechanical seals, agitator with dual mechanical seals, pump with no external shaft, agitator with no external shaft; the entity may exclude from monitoring each pressure relief device in gas and vapor service with upstream rupture disk, each sampling connection system with closed-loop or closed-purge systems, and any pieces of equipment where leaks are routed through a closed vent system to a destruction unit. The entity must estimate emissions using another approach for those pieces of equipment excluded from monitoring. Equipment that is in controlled substance service for less than 300 hr/yr, equipment that is in vacuum service, pressure relief devices that are in light liquid service, and instrumentation systems are exempted from the requirements in this paragraph (c)(2).

(i) The emissions from equipment leaks must be calculated using any of the procedures in paragraphs (c)(2)(i)(A), (B), (C), or (D) of this section.

(A) Use of Average Emission Factor Approach in EPA protocol for equipment leak emission estimates. The emissions from equipment leaks may be calculated using the default Average Emission Factor Approach in EPA-453/R-95-017 (incorporated by reference, see § 82.27).

(B) Use of Other Approaches in EPA protocol for equipment leak emission estimates in conjunction with EPA Method 21. The emissions from equipment leaks may be calculated using one of the following methods in EPA-453/R-95-017 (incorporated by reference, see § 82.27): The Screening Ranges Approach; the EPA Correlation Approach; or the Unit-Specific Correlation Approach. If it is determined that EPA Method 21 in appendix A-7 to 40 CFR part 60 is appropriate for monitoring a controlled substance, and if the instrument is calibrated with a compound different from one or more of the controlled substances or surrogates to be measured, each entity must develop response factors for each controlled substance or for each surrogate to be measured using EPA Method 21. For each controlled substance or surrogate measured, the response factor must be less than 10. The response factor is the ratio of the known concentration of a controlled substance or surrogate to the observed meter reading when measured using an instrument calibrated with the reference compound.

(C) Use of Other Approaches in EPA protocol for equipment leak emission estimates in conjunction with site-specific leak monitoring methods. The emissions from equipment leaks may be calculated using one of the following methods in EPA-453/R-95-017 (incorporated by reference, see § 82.27): The Screening Ranges Approach; the EPA Correlation Approach; or the Unit-Specific Correlation Approach. Each entity may develop a site-specific leak monitoring method appropriate for monitoring controlled substances or surrogates to use along with these three approaches. The site-specific leak monitoring method must meet the requirements in paragraph (d)(5)(i) of this section.

(D) Use of site-specific leak monitoring methods. The emissions from equipment leaks may be calculated using a site-specific leak monitoring method. The site-specific leak monitoring method must meet the requirements in paragraph (d)(5)(i) of this section.

(ii) Each entity must collect information on the number of each type of equipment, the service of each piece of equipment (gas, light liquid, heavy liquid), the concentration of each controlled substance in the stream, and the time period each piece of equipment was in service (e.g., hours per year). Depending on which approach followed, the entity may be required to collect information for equipment on the associated screening data concentrations for greater than or equal to 10,000 ppmv and associated screening data concentrations for less than 10,000 ppmv; associated actual screening data concentrations; or associated screening data and leak rate data (i.e., bagging) used to develop a unit-specific correlation.

(iii) Calculate and sum the emissions of each controlled substance in kilograms per year for equipment pieces for each process, EELp, annually. Each entity must include and estimate emissions for types of equipment that are excluded from monitoring, including difficult-to-monitor, unsafe-to-monitor and insulated pieces of equipment, pieces of equipment in heavy liquid service, pumps with dual mechanical seals, agitators with dual mechanical seals, pumps with no external shaft, agitators with no external shaft, pressure relief devices in gas and vapor service with upstream rupture disk, sampling connection systems with closed-loop or closed purge systems, and pieces of equipment where leaks are routed through a closed vent system to a destruction unit.

(3) Calculate total controlled substance emissions for each process and for production or transformation processes at the facility. (i) Estimate annually the total mass of each controlled substance emitted from each process, including emissions from process vents in paragraphs (c)(1)(iii) and (iv) of this section, as appropriate, and from equipment leaks in paragraph (c)(2) of this section, using equation 10 to this paragraph (c)(3)(i).

Equation 10 to Paragraph (c)(3)(i) Ei = EPpi + EELpi Where: Ei = Total mass of each controlled substance p emitted from process i, annual basis (kg/year). EPpi = Mass of controlled substance p emitted from all process vents and all operating scenarios in process i, annually (kg/year, calculated in equation 5 or 9 to this section, as appropriate). EELpi = Mass of controlled substance p emitted from equipment leaks for pieces of equipment for process i, annually (kg/year, calculated in paragraph (c)(2)(iii) of this section).

(ii) Estimate annually the total mass of each controlled substance emitted at the facility from each applicable process listed in paragraph (b)(2) of this section using equation 11 to this paragraph (c)(3)(ii). Develop separate totals for each applicable process listed in paragraph (b)(2) of this section.

Equation 11 to Paragraph (c)(3)(ii) Where: E = Total mass of each controlled substance p emitted from all processes listed in paragraphs (b)(2)(i) through (iv) of this section, as appropriate (kilograms). Ei = Total mass of each controlled substance p emitted from each process listed in paragraphs (b)(2)(i) through (iv) of this section, annual basis (kg/year, calculated in equation 10 to paragraph (c)(3)(i) of this section). z = Total number of processes listed in paragraphs (b)(2)(i) through (iv) of this section, as appropriate.

(4) Mass balance method. Before using the mass balance approach to estimate your controlled substance emissions from a process, you must ensure that the process and the equipment and methods used to measure the process meet either the error limits described in this paragraph (c)(4) and calculated under paragraph (c)(4)(i) of this section or the requirements specified in paragraph (d)(4)(viii) of this section. If you choose to calculate the error limits, you must estimate the absolute and relative errors associated with using the mass balance approach on that process using equations 12 through 15 to this section in conjunction with equations 16 through 21 to this section. You may use the mass-balance approach to estimate emissions from the process if this calculation results in an absolute error of less than or equal to one metric ton of controlled substance per year or a relative error of less than or equal to 10 percent of the estimated controlled substance emissions. If you do not meet either of the error limits or the requirements of paragraph (d)(4)(viii) of this section, you must use the emission factor approach detailed in paragraphs (c)(1) through (3) of this section to estimate emissions from the process.

(i) To perform the calculation, you must first calculate the absolute and relative errors associated with the quantities calculated using either equations 18 through 21 to this section or equation 28 to paragraph (c)(4)(xv) of this section. Alternatively, you may estimate these errors based on the variability of previous process measurements (e.g., the variability of measurements of stream concentrations), provided these measurements are representative of the current process and current measurement devices and techniques. Once errors have been calculated for the quantities in these equations, those errors must be used to calculate the errors in equations 16 and 17 to this section. You may omit the errors associated with equations 22 through 24 to this section.

(A) Where the measured quantity is a mass, the error in the mass must be equated to the accuracy or precision (whichever is larger) of the flowmeter, scale, or combination of volumetric and density measurements at the flow rate or mass measured.

(B) Where the measured quantity is a concentration of a stream component, the error of the concentration must be equated to the accuracy or precision (whichever is larger) with which you estimate the mean concentration of that stream component, accounting for the variability of the process, the frequency of the measurements, and the accuracy or precision (whichever is larger) of the analytical technique used to measure the concentration at the concentration measured. If the variability of process measurements is used to estimate the error, this variability shall be assumed to account both for the variability of the process and the precision of the analytical technique. Use standard statistical techniques such as the student's t distribution to estimate the error of the mean of the concentration measurements as a function of process variability and frequency of measurement.

(C) Equation 12 to this paragraph (c)(4)(i)(C) provides the general formula for calculating the absolute errors of sums and differences where the sum, S, is the summation of variables measured, a, b, c, etc. (e.g., S = a + b + c).

Equation 12 to Paragraph (c)(4)(i)(C) eSA = [(a * ea) 2 + (b * eb) 2 + (c * ec) 2] 1/2 Where: eSA = Absolute error of the sum, expressed as one half of a 95 percent confidence interval. ea = Relative error of a, expressed as one half of a 95 percent confidence interval. eb = Relative error of b, expressed as one half of a 95 percent confidence interval. ec = Relative error of c, expressed as one half of a 95 percent confidence interval.

(D) Equation 13 to this paragraph (c)(4)(i)(D) provides the general formula for calculating the relative errors of sums and differences.

Equation 13 to Paragraph (c)(4)(i)(D) Where: eSR = Relative error of the sum, expressed as one half of a 95 percent confidence interval. eSA = Absolute error of the sum, expressed as one half of a 95 percent confidence interval. a+b+c = Sum of the variables measured.

(E) Equation 14 to this paragraph (c)(4)(i)(E) provides the general formula for calculating the absolute errors of products (e.g., flow rates of controlled substances calculated as the product of the flow rate of the stream and the concentration of the controlled substance in the stream), where the product, P, is the result of multiplying the variables measured, a, b, c, etc. (e.g., P = a*b*c).

Equation 14 to Paragraph (c)(4)(i)(E) ePA = (a * b * c)(e 2a + e 2b + e 2c) 1/2 Where: ePA = Absolute error of the product, expressed as one half of a 95 percent confidence interval. ea = Relative error of a, expressed as one half of a 95 percent confidence interval. eb = Relative error of b, expressed as one half of a 95 percent confidence interval. ec = Relative error of c, expressed as one half of a 95 percent confidence interval.

(F) Equation 15 to this paragraph (c)(4)(i)(F) provides the general formula for calculating the relative errors of products.

Equation 15 to Paragraph (c)(4)(i)(F) Where: ePR = Relative error of the product, expressed as one half of a 95 percent confidence interval. ePA = Absolute error of the product, expressed as one half of a 95 percent confidence interval. a*b*c = Product of the variables measured.

(G) Calculate the absolute error of the controlled substance emissions estimate by performing a preliminary estimate of the annual controlled substance emissions of the process using the method in paragraph (c)(4)(i)(H) of this section. Multiply this result by the relative error calculated for the mass of halogen emitted from the process in equation 15 to paragraph (c)(4)(i)(F) of this section.

(H) To estimate the annual controlled substance emissions of the process for use in the error estimate, apply the methods set forth in paragraphs (c)(4)(ii) through (vii) and (ix) through (xvi) of this section to representative process measurements. If these process measurements represent less than one year of typical process activity, adjust the estimated emissions to account for one year of typical process activity. To estimate the terms FERd, FEP, and FEBk for use in the error estimate for equations 22, 23, and 24 to this section, you must either use emission testing, monitoring of emitted streams, and/or engineering calculations or assessments.

(ii) The total mass of each controlled substance emitted annually from each controlled substance process must be estimated by using equation 16 to this paragraph (c)(4)(ii).

Equation 16 to Paragraph (c)(4)(ii) Where: EContp = Total mass of each controlled substance p emitted annually from process i (metric tons). ERp-FContp = Total mass of controlled substance reactant p emitted from production process i over the period t (metric tons, calculated in equation 22 to paragraph (c)(4)(ix) of this section). EPp-FContp= Total mass of the controlled substance product p emitted from production process i over the period t (metric tons, calculated in equation 23 to paragraph (c)(4)(x) of this section). EBp-FContp = Total mass of controlled substance byproduct p emitted from production process i over the period t (metric tons, calculated in equation 24 to paragraph (c)(4)(xi) of this section). n = Number of concentration and flow measurement periods for the year.

(iii) The total mass of halogen emitted from process i over the period t must be estimated at least monthly by calculating the difference between the total mass of halogen in the reactant(s) (or inputs, for processes that do not involve a chemical reaction) and the total mass of halogen in the product (or outputs, for processes that do not involve a chemical reaction), accounting for the total mass of halogen in any destroyed or recaptured streams that contain reactants, products, or byproducts (or inputs or outputs). This calculation must be performed using equation 17 to this paragraph (c)(4)(iii). An element other than a halogen may be used in the mass-balance equation, provided the element occurs in all of the controlled substances fed into or generated by the process. In this case, the mass fractions of the element in the reactants, products, and byproducts must be calculated as appropriate for that element.

Equation 17 to Paragraph (c)(4)(iii) Where: EH = Total mass of halogen emitted from process i over the period t (metric tons). Rd = Total mass of the halogen-containing reactant d that is fed into process i over the period t (metric tons). P = Total mass of the halogen-containing product produced by process i over the period t (metric tons). MFHRd = Mass fraction of halogen in reactant d, calculated in equation 25 to paragraph (c)(4)(xii) of this section. MFHP = Mass fraction of halogen in the product, calculated in equation 26 to paragraph (c)(4)(xiii) of this section. FD = Total mass of halogen in destroyed or recaptured streams from process i containing halogen-containing reactants, products, and byproducts over the period t, calculated in equation 18 to paragraph (c)(4)(iv) of this section. v = Number of halogen-containing reactants fed into process i.

(iv) The mass of total halogen in destroyed or recaptured streams containing halogen-containing reactants, products, and byproducts must be estimated at least monthly using equation 18 to this paragraph (c)(4)(iv) unless you use the alternative approach provided in paragraph (c)(4)(xv) of this section.

Equation 18 to Paragraph (c)(4)(iv) Where: FD = Total mass of halogen in destroyed or recaptured streams from process i containing halogen-containing reactants, products, and byproducts over the period t. Pj = Mass of the halogen-containing product removed from process i in stream j and destroyed over the period t (calculated in equation 19 or 20 to this section). Bkj = Mass of halogen-containing byproduct k removed from process i in stream j and destroyed over the period t (calculated in equation 19 or 20 to this section). Bkl = Mass of halogen-containing byproduct k removed from process i in stream l and recaptured over the period t. Rdj = Mass of halogen-containing reactant d removed from process i in stream j and destroyed over the period t (calculated in equation 19 or 20 to this section). MFHRd = Mass fraction of halogen in reactant d, calculated in equation 25 to paragraph (c)(4)(xii) of this section. MFHP = Mass fraction of halogen in the product, calculated in equation 26 to paragraph (c)(4)(xiii) of this section. MFHBk = Mass fraction of halogen in byproduct k, calculated in equation 27 to paragraph (c)(4)(xiv) of this section. q = Number of streams destroyed in process i. x = Number of streams recaptured in process i. u = Number of halogen-containing byproducts generated in process i. v = Number of halogen-containing reactants fed into process i.

(v) The mass of each controlled substance removed from process i in stream j and destroyed over the period t (i.e., Pj, Bkj, or Rdj, as applicable) must be estimated by applying the destruction efficiency of the device that has been demonstrated for the controlled substance p to controlled substance f using equation 19 to this paragraph (c)(4)(v).

Equation 19 to Paragraph (c)(4)(v) MFcontpj = DEContp * Ccontrpj * Sj Where: MFContpj = Mass of controlled substance p removed from process i in stream j and destroyed over the period t. (This may be Pj, Bkj, or Rdj, as applicable.) DEContp = Destruction efficiency of the device that has been demonstrated for controlled substance p in stream j (fraction). CContpj = Concentration (mass fraction) of controlled substance p in stream j removed from process i and fed into the destruction device over the period t. If this concentration is only a trace concentration, cContrpj is equal to zero. Sj = Mass removed in stream j from process i and fed into the destruction device over the period t (metric tons).

(vi) The mass of each halogen-containing compound that is not a controlled substance and that is removed from process i in stream j and destroyed over the period t (i.e., P>j, B>kj, or R>dj, as applicable) must be estimated using equation 20 to this paragraph (c)(4)(vi).

Equation 20 to Paragraph (c)(4)(vi) Mhcgj = CHCgj * Sj Where: MHCgj = Mass of non-controlled substance halogen-containing compound g removed from process i in stream j and destroyed over the period t. (This may be Pj, Bkj, or Rdj, as applicable.) CHCgj = Concentration (mass fraction) of non-controlled substance halogen-containing compound g in stream j removed from process i and fed into the destruction device over the period t. If this concentration is only a trace concentration, cHCgj is equal to zero. Sj = Mass removed in stream j from process i and fed into the destruction device over the period t (metric tons).

(vii) The mass of halogen-containing byproduct k removed from process i in stream l and recaptured over the period t must be estimated using equation 21 to this paragraph (c)(4)(vii).

Equation 21 to Paragraph (c)(4)(vii) Bkl = CBkl * Sl Where: Bkl = Mass of halogen-containing byproduct k removed from process i in stream l and recaptured over the period t (metric tons). cBkl = Concentration (mass fraction) of halogen-containing byproduct k in stream l removed from process i and recaptured over the period t. If this concentration is only a trace concentration, cBkl is equal to zero. Sl = Mass removed in stream l from process i and recaptured over the period t (metric tons).

(viii) To estimate the terms FERd, FEP, and FEBk for equations 22, 23, and 24 to this section, you must account for the total mass of halogen emitted, EF, estimated in equation 17 to paragraph (c)(4)(iii) of this section. These emission characterization measurements must meet the requirements in paragraph (c)(4)(viii)(A), (B), or (C) of this section, as appropriate. The sum of the terms must equal 1. You must document the data and calculations that are used to speciate individual compounds and to estimate FERd, FEP, and FEBk. Exclude from your calculations the halogen included in FD. For example, exclude halogen-containing compounds that are not controlled substances and that result from the destruction of controlled substances by any destruction devices (e.g., the mass of HF created by combustion of a chlorofluorocarbon). However, include emissions of controlled substance that survive the destruction process.

(A) If the calculations under paragraph (b)(1)(viii) of this section, or any subsequent measurements and calculations under this subpart, indicate that the process emits 0.1 metric tons controlled substance or more, estimate the emissions from each process vent, considering controls, using the methods in paragraph (c)(1)(i) of this section. You must characterize the emissions of any process vent that emits 0.1 metric tons controlled substance or more as specified in paragraph (d)(4)(iv) of this section.

(B) For other vents, including vents from processes that emit less than 0.1 metric tons of controlled substance, you must characterize emissions as specified in paragraph (d)(4)(v) of this section.

(C) For halogen emissions that are not accounted for by vent estimates, you must characterize emissions as specified in paragraph (d)(4)(vi) of this section.

(ix) The total mass of halogen-containing reactant d emitted must be estimated at least monthly based on the total halogen emitted and the fraction that consists of halogen-containing reactants using equation 22 to this paragraph (c)(4)(ix). If the halogen-containing reactant d is not a controlled substance, you may assume that FERd is zero.

Equation 22 to Paragraph (c)(4)(ix) Where: ER-it = Total mass of halogen-containing reactant d that is emitted from process i over the period t (metric tons). FERd = The fraction of the mass emitted that consists of the halogen-containing reactant d. EH = Total mass of halogen emissions from process i over the period t (metric tons), calculated in equation 17 to paragraph (c)(4)(iii) of this section. FEP = The fraction of the mass emitted that consists of the halogen-containing product. FEBk = The fraction of the mass emitted that consists of halogen-containing byproduct k. MFFRd = Mass fraction of halogen in reactant d, calculated in equation 25 to paragraph (c)(4)(xii) of this section. MFHP = Mass fraction of halogen in the product, calculated in equation 26 to paragraph (c)(4)(xiii) of this section. MFHBk = Mass fraction of halogen in byproduct k, calculation in equation 27 to paragraph (c)(4)(xiv) of this section. u = Number of halogen-containing byproducts generated in process i. v = Number of halogen-containing reactants fed into process i.

(x) The total mass of halogen-containing product emitted must be estimated at least monthly based on the total halogen emitted and the fraction that consists of halogen-containing products using equation 23 to this paragraph (c)(4)(x). If the halogen-containing product is not a controlled substance, you may assume that FEP is zero.

Equation 23 to Paragraph (c)(4)(x) Where: EP-it = Total mass of halogen-containing product emitted from process i over the period t (metric tons). FEP = The fraction of the mass emitted that consists of the halogen-containing product. EH = Total mass of halogen emissions from process i over the period t (metric tons), calculated in equation 17 to paragraph (c)(4)(iii) of this section. FERd = The fraction of the mass emitted that consists of halogen-containing reactant d. FEBk = The fraction of the mass emitted that consists of halogen-containing byproduct k. MFHRd = Mass fraction of halogen in reactant d, calculated in equation 25 to paragraph (c)(4)(xii) of this section. MFHP = Mass fraction of halogen in the product, calculated in equation 26 to paragraph (c)(4)(xiii) of this section. MFHBk = Mass fraction of halogen in byproduct k, calculation in equation 27 to paragraph (c)(4)(xiv) of this section. u = Number of halogen-containing byproducts generated in process i. v = Number of halogen-containing reactants fed into process i.

(xi) The total mass of halogen-containing byproduct k emitted must be estimated at least monthly based on the total halogen emitted and the fraction that consists of halogen-containing byproducts using equation 24 to this paragraph (c)(4)(xi). If halogen-containing byproduct k is not a controlled substance, you may assume that FEBk is zero.

Equation 24 to Paragraph (c)(4)(xi) Where: EBk-it = Total mass of halogen-containing byproduct k emitted from process i over the period t (metric tons). FEBk = The fraction of the mass emitted that consists of halogen-containing byproduct k. FERd = The fraction of the mass emitted that consists of halogen-containing reactant d. FEP = The fraction of the mass emitted that consists of the halogen-containing product. EH = Total mass of halogen emissions from process i over the period t (metric tons), calculated in equation 17 to paragraph (c)(4)(iii) of this section. MFHRd = Mass fraction of halogen in reactant d, calculated in equation 25 to paragraph (c)(4)(xii) of this section. MFHP = Mass fraction of halogen in the product, calculated in equation 26 to paragraph (c)(4)(xiii) of this section. MFHBk = Mass fraction of halogen in byproduct k, calculation in equation 27 to paragraph (c)(4)(xiv) of this section. u = Number of halogen-containing byproducts generated in process i. v = Number of halogen-containing reactants fed into process i.

(xii) The mass fraction of halogen in reactant d must be estimated using equation 25 to this paragraph (c)(4)(xii).

Equation 25 to Paragraph (c)(4)(xii) Where: MFHRd = Mass fraction of halogen in reactant d (fraction). MHRd = Moles halogen per mole of reactant d. AWH = Atomic weight of halogen. MWRd = Molecular weight of reactant d.

(xiii) The mass fraction of halogen in the product must be estimated using equation 26 to this paragraph (c)(4)(xiii).

Equation 26 to Paragraph (c)(4)(xiii) Where: MFHP = Mass fraction of halogen in the product (fraction). MHP = Moles halogen per mole of product. AWH = Atomic weight of halogen. MWP = Molecular weight of the product produced.

(xiv) The mass fraction of each applicable halogen in byproduct k must be estimated using equation 27 to this paragraph (c)(4)(xiv).

Equation 27 to Paragraph (c)(4)(xiv) Where: MFHBk = Mass fraction of halogen in the product (fraction). MHBk = Moles halogen per mole of byproduct k. AWH = Atomic weight of halogen. MWBk = Molecular weight of byproduct k.

(xv) As an alternative to using equation 18 to paragraph (c)(4)(iv) of this section as provided in paragraph (b)(4) of this section, you may estimate at least monthly the total mass of halogen in destroyed or recaptured streams containing halogen-containing compounds (including all halogen-containing reactants, products, and byproducts) using equation 28 to this paragraph (c)(4)(xv).

Equation 28 to Paragraph (c)(4)(xv) Where: FD = Total mass of halogen in destroyed or recaptured streams from process i containing halogen-containing reactants, products, and byproducts over the period t. DEavgj = Weighted average destruction efficiency of the destruction device for the halogen-containing compounds identified in destroyed stream j under paragraphs (d)(4)(iv)(B) and (d)(4)(v)(B) of this section (calculated in equation 28 to this paragraph (c)(4)(xv)) (fraction). cTHj = Concentration (mass fraction) of total halogen in stream j removed from process i and fed into the destruction device over the period t. If this concentration is only a trace concentration, cTHj is equal to zero. Sj = Mass removed in stream j from process i and fed into the destruction device over the period t (metric tons). cTHl = Concentration (mass fraction) of total halogen in stream l removed from process i and recaptured over the period t. If this concentration is only a trace concentration, cBkl is equal to zero. Sl = Mass removed in stream l from process i and recaptured over the period t. q = Number of streams destroyed in process i. x = Number of streams recaptured in process i.

(xvi) For purposes of equation 28 to paragraph (c)(4)(xv) of this section, calculate the weighted average destruction efficiency applicable to a destroyed stream using equation 29 to this paragraph (c)(4)(xvi).

Equation 29 to Paragraph (c)(4)(xvi) Where: DEavgj = Weighted average destruction efficiency of the destruction device for the halogen-containing compounds identified in destroyed stream j under paragraph (d)(4)(iv)(B) or (d)(4)(v)(B) of this section, as appropriate. DEContp = Destruction efficiency of the device that has been demonstrated for controlled substance p in stream j (fraction). cContpj = Concentration (mass fraction) of controlled substance p in stream j removed from process i and fed into the destruction device over the period t. If this concentration is only a trace concentration, cContpj is equal to zero. cHCgj = Concentration (mass fraction) of non-controlled substance halogen-containing compound g in stream j removed from process i and fed into the destruction device over the period t. If this concentration is only a trace concentration, cHCgj is equal to zero. Sj = Mass removed in stream j from process i and fed into the destruction device over the period t (metric tons). MFHContp = Mass fraction of halogen in controlled substance p, calculated in equation 25, 26, or 27 to this section, as appropriate. MFHHCg = Mass fraction of halogen in non-controlled substance halogen-containing compound g, calculated in equation 25, 26, or 27 to this section, as appropriate. w = Number of controlled substances in destroyed stream j. y = Number of non-controlled substance halogen-containing compounds in destroyed stream j.

(5) Calculate controlled substance emissions from destruction of controlled substances. Estimate annually the total mass of controlled substances emitted annually from destruction of controlled substances using equation 30 to this paragraph (c)(5):

Equation 30 to Paragraph (c)(5) ED = RED * (1−DE) Where: ED = The mass of controlled substances emitted annually from destruction of controlled substances (kilograms). RED = The mass of controlled substances that are fed annually into the destruction unit (kilograms). DE = Destruction efficiency of the destruction unit (fraction).

(6) Effective destruction efficiency for each process. If using the emission factor or emission calculation factor method to calculate emissions from the process, use equation 31 to this paragraph (c)(6) to calculate the effective destruction efficiency for the process, including each process vent:

Equation 31 to Paragraph (c)(6) Where: DEEffective = Effective destruction efficiency for process i (fraction). EPVp = Mass of controlled substance p emitted from process vent v from process i, operating scenario j, for the year, calculated in equation 3, 7, or 8 to this section (kg). ECFPV-Up = Emission calculation factor for controlled substance p emitted from process vent v during process i, operating scenario j, as used in equation 7 or 8 to this section (kg emitted/activity) (e.g., kg emitted/kg product), denoted as “ECFPV” in those equations. EFPV-Up = Emission factor (uncontrolled) for controlled substance p emitted from process vent v during process i, operating scenario j, as used in equation 3 to paragraph (c)(1)(iii)(F) of this section (kg emitted/activity) (e.g., kg emitted/kg product), denoted as “EFPV-U” in that equation. ActivityU = Total process feed, process production, or other process activity for process i, operating scenario j during the year, for which the process vent is not vented to the properly functioning destruction unit (i.e., uncontrolled). ActivityC = Total process feed, process production, or other process activity for process i, operating scenario j during the year, for which emissions are vented to the properly functioning destruction unit (i.e., controlled). o = Number of operating scenarios for process i. v = Number of process vents in process i, operating scenario j. w = Number of controlled substances emitted from the process.

(d) Monitoring and QA/QC requirements—(1) Initial scoping speciation to identify controlled substances from transformation processes. Each entity that transforms controlled substances must conduct an initial scoping speciation to identify all controlled substances that may be generated or emitted from transformation processes that are subject to this section. The entity is not required to quantify emissions under this initial scoping speciation. Only controlled substance products and byproducts that occur in greater than trace concentrations in at least one stream must be identified under this paragraph (d)(1).

(i) Procedure. To conduct the scoping speciation, select the stream(s) (including process streams or destroyed streams) or process vent(s) that would be expected to individually or collectively contain all of the controlled substance byproducts of the process at their maximum concentrations and sample and analyze the contents of these selected streams or process vents. For example, if controlled substance byproducts are separated into one low-boiling-point and one high-boiling-point stream, sample and analyze both of these streams. Alternatively, each entity may sample and analyze streams where controlled substance byproducts occur at less than their maximum concentrations, but the entity must ensure that the sensitivity of the analysis is sufficient to compensate for the expected difference in concentration. For example, if the entity samples and analyzes streams where controlled substance byproducts are expected to occur at one half their maximum concentrations elsewhere in the process, that entity must ensure that the sensitivity of the analysis is sufficient to detect controlled substance byproducts that occur at concentrations of 0.05 percent or higher. The entity does not have to sample and analyze every stream or process vent, i.e., the entity does not have to sample and analyze a stream or process vent that contains only controlled substances that are contained in other streams or process vents that are being sampled and analyzed. Sampling and analysis must be conducted according to the procedures in paragraph (d)(5) of this section.

(ii) Previous measurements. If testing of streams (including process streams or destroyed streams) or process vents were conducted less than 5 years before November 12, 2024, and the testing meets the requirements in paragraph (d)(1)(i) of this section, each entity may use the previous testing to satisfy this requirement.

(2) Emission factor testing. If controlled substance emissions are determined using the site-specific process-vent-specific emission factor, each entity must meet the requirements in paragraphs (d)(2)(i) through (vii) of this section.

(i) Process vent testing. Conduct an emissions test that is based on representative performance of the process or operating scenario(s) of the process, as applicable. For process vents for which each entity performed an initial scoping speciation, include in the emission test any controlled substance that was identified in the initial scoping speciation. For process vents for which the entity did not perform an initial scoping speciation, include in the emission test any controlled substance that occurs in more than trace concentrations in the vent stream or, where a destruction unit is used, in the inlet to the destruction unit. The entity may include startup and shutdown events if the testing is sufficiently long or comprehensive to ensure that such events are not overrepresented in the emission factor. Malfunction events must not be included in the testing. If the entity does not detect a controlled substance that was identified in the scoping speciation or that occurs in more than trace concentrations in the vent stream or in the inlet to the destruction unit, assume that controlled substance was emitted from the process vent, or from the destruction unit, at a concentration of one third of the detection limit.

(ii) Number of runs. For continuous processes, sample the process vent for a minimum of three runs of 1 hour each. If the relative standard deviation (RSD) of the emission factor calculated based on the first three runs is greater than or equal to 0.15 for the emission factor, continue to sample the process vent for an additional three runs of 1 hour each.

(iii) Process activity measurements. Determine the mass rate of process feed, process production, or other process activity as applicable during the test using flow meters, weigh scales, or other measurement devices or instruments with an accuracy and precision of ±1 percent of full scale or better. These devices may be the same plant instruments or procedures that are used for accounting purposes (such as weigh hoppers, belt weigh feeders, combination of volume measurements and bulk density, etc.) if these devices or procedures meet the requirement. For monitoring ongoing process activity, use flow meters, weigh scales, or other measurement devices or instruments with an accuracy and precision of ±1 percent of full scale or better.

(iv) Sample each process. If process vents from separate processes are manifolded together to a common vent or to a common destruction unit, each entity must follow paragraph (d)(2)(iv)(A), (B), or (C) of this section.

(A) Each entity may sample emissions from each process in the ducts upstream from the point where the emissions are combined.

(B) Each entity may sample in the common duct or at the outlet of the destruction unit when only one process is operating.

(C) Each entity may sample the combined emissions and use engineering calculations and assessments as specified in paragraph (c)(1)(iv) of this section to allocate the emissions to each manifolded process vent, provided the sum of the calculated controlled substance emissions across the individual process vents is within 20 percent of the total controlled substance emissions measured during the manifolded testing.

(v) Emission test results. The results of an emission test must include the analysis of samples, number of test runs, the results of the RSD analysis, the analytical method used, determination of emissions, the process activity, and raw data and must identify the process, the operating scenario, the process vents tested, and the controlled substances that were included in the test. The emissions test report must contain all information and data used to derive the process-vent-specific emission factor, as well as key process conditions during the test. Key process conditions include those that are normally monitored for process control purposes and may include but are not limited to yields, pressures, temperatures, etc. (e.g., of reactor vessels, distillation columns).

(vi) Emissions testing frequency. Each entity must conduct emissions testing to develop the process-vent-specific emission factor under paragraph (d)(2)(vi)(A) or (B) of this section, whichever occurs first:

(A) 5-year revision. Conduct an emissions test every 5 years. In the calculations under paragraph (c) of this section, apply the revised process-vent-specific emission factor to the process activity that occurs after the revision.

(B) Operating scenario change that affects the emission factor. For planned operating scenario changes, each entity must estimate and compare the emission calculation factors for the changed operating scenario and for the original operating scenario whose process vent specific emission factor was measured. Use the calculation methods in paragraph (c)(1)(iv) of this section. If the emission calculation factor for the changed operating scenario is 15 percent or more different from the emission calculation factor for the previous operating scenario (this includes the cumulative change in the emission calculation factor since the most recent emissions test), the entity must conduct an emissions test to update the process-vent-specific emission factor, unless the difference between the operating scenarios is solely due to the application of a destruction unit to emissions under the changed operating scenario. Conduct the test before February 14 of the calendar year that immediately follows the change. In the calculations under paragraph (c) of this section, apply the revised process-vent-specific emission factor to the process activity that occurs after the operating scenario change.

(vii) Previous measurements. If an emissions test was conducted less than 5 years before November 12, 2024, and the emissions testing meets the requirements in paragraphs (d)(2)(i) through (vii) of this section, the entity may use the previous emissions testing to develop process-vent-specific emission factors. For purposes of paragraph (d)(2)(vi)(A) of this section, the date of the previous emissions test rather than November 12, 2024, shall constitute the beginning of the 5-year re-measurement cycle.

(3) Emission calculation factor monitoring. If controlled substance emissions were determined using the site-specific process-vent-specific emission calculation factor, each entity must meet the requirements in paragraphs (d)(3)(i) through (iv) of this section.

(i) Operating scenario. Perform the emissions calculation for the process vent based on representative performance of the operating scenario of the process. If more than one operating scenario applies to the process that contains the subject process vent, you must conduct a separate emissions calculation for operation under each operating scenario. For each continuous process vent that contains more than trace concentrations of any controlled substance and for each batch process vent that contains more than trace concentrations of any controlled substance, develop the process-vent-specific emission calculation factor for each operating scenario. For continuous process vents, determine the emissions based on the process activity for the representative performance of the operating scenario. For batch process vents, determine emissions based on the process activity for each typical batch operating scenario.

(ii) Process activity measurements. Use flow meters, weigh scales, or other measurement devices or instruments with an accuracy and precision of ±1 percent of full scale or better for monitoring ongoing process activity.

(iii) Emission calculation results. The emission calculation must be documented by identifying the process, the operating scenario, and the process vent(s). The documentation must contain the information and data used to calculate the process-vent-specific emission calculation factor.

(iv) Operating scenario change that affects the emission calculation factor. For planned operating scenario changes that are expected to change the process-vent-specific emission calculation factor, each entity must conduct an emissions calculation to update the process-vent-specific emission calculation factor. In the calculations under paragraph (c) of this section, apply the revised emission calculation factor to the process activity that occurs after the operating scenario change.

(v) Previous calculations. If an emissions calculation was performed for the process vent and operating scenario less than 5 years before November 12, 2024, and the emissions calculation meets the requirements in paragraphs (c)(1)(iv)(A) and (B) of this section and in paragraphs (d)(3)(i) through (iv) of this section, each entity may use the previous calculation to develop the site-specific process-vent-specific emission calculation factor.

(4) Mass balance monitoring. If you determine controlled substance emissions from any process using the mass balance method under paragraph (c)(4) of this section, you must estimate the total mass of each controlled substance emitted from that process at least monthly. Only streams that contain greater than trace concentrations of halogen-containing reactants, products, or byproducts must be monitored under this paragraph (d)(4).

(i) Mass measurements. Measure the following masses on a monthly or more frequent basis using flowmeters, weigh scales, or a combination of volumetric and density measurements with accuracies and precisions that allow the facility to meet the error criteria in paragraph (c)(4)(i) of this section:

(A) Total mass of each halogen-containing product produced. Account for any used halogen-containing product added into the production process upstream of the output measurement as directed at §§ 98.413(b) and 98.414(b) of this chapter.

(B) Total mass of each halogen-containing reactant fed into the process.

(C) The mass removed from the process in each stream fed into the destruction device.

(D) The mass removed from the process in each recaptured stream.

(ii) Concentration measurements for use with paragraph (c)(4)(iv) of this section. If you use paragraph (c)(4)(iv) of this section to estimate the mass of halogen in destroyed or recaptured streams, measure the following concentrations at least once each calendar month during which the process is operating, on a schedule to ensure that the measurements are representative of the full range of process conditions (e.g., catalyst age). Measure more frequently if this is necessary to meet the error criteria in paragraph (c)(4)(i) of this section. Use equipment and methods (e.g., gas chromatography) that comply with paragraph (d)(5) of this section and that have an accuracy and precision that allow the facility to meet the error criteria in paragraph (c)(4)(i) of this section. Only halogen-containing reactants, products, and byproducts that occur in a stream in greater than trace concentrations must be monitored under this paragraph (d)(4)(ii).

(A) The concentration (mass fraction) of the halogen-containing product in each stream that is fed into the destruction device.

(B) The concentration (mass fraction) of each halogen-containing byproduct in each stream that is fed into the destruction device.

(C) The concentration (mass fraction) of each halogen-containing reactant in each stream that is fed into the destruction device.

(D) The concentration (mass fraction) of each halogen-containing byproduct in each stream that is recaptured (cBkl).

(iii) Concentration measurements for use with paragraph (c)(4)(xv) of this section. If you use paragraph (c)(4)(xv) of this section to estimate the mass of halogen in destroyed or recaptured streams, measure the concentrations listed in paragraphs (d)(4)(iii)(A) and (B) of this section at least once each calendar month during which the process is operating, on a schedule to ensure that the measurements are representative of the full range of process conditions (e.g., catalyst age). Measure more frequently if this is necessary to meet the error criteria in paragraph (c)(4)(i) of this section. Use equipment and methods (e.g., gas chromatography) that comply with paragraph (d)(5) of this section and that have an accuracy and precision that allow the facility to meet the error criteria in paragraph (c)(4)(i) of this section. Only halogen-containing reactants, products, and byproducts that occur in a stream in greater than trace concentrations must be monitored under this paragraph (d)(4)(iii).

(A) The concentration (mass fraction) of total halogen in each stream that is fed into the destruction device.

(B) The concentration (mass fraction) of total halogen in each stream that is recaptured.

(iv) Emissions characterization: process vents emitting 0.1 metric tons or more. To characterize emissions from any process vent emitting 0.1 metric tons of controlled substances or more, comply with paragraphs (d)(4)(iv)(A) through (E) of this section, as appropriate. Only halogen-containing reactants, products, and byproducts that occur in a stream in greater than trace concentrations must be monitored under this paragraph (d)(4)(iv).

(A) Uncontrolled emissions. If emissions from the process vent are not routed through a destruction device, sample and analyze emissions at the process vent or stack or sample and analyze emitted streams before the process vent. If the process has more than one operating scenario, you must either perform the emission characterization for each operating scenario or perform the emission characterization for the operating scenario that is expected to have the largest emissions and adjust the emission characterization for other scenarios using engineering calculations and assessments as specified in paragraph (c)(1)(iv) of this section. To perform the characterization, take three samples under conditions that are representative for the operating scenario. Measure the concentration of each halogen-containing compound in each sample. Use equipment and methods that comply with paragraph (d)(5) of this section. Calculate the average concentration of each halogen-containing compound across all three samples.

(B) Controlled emissions using paragraph (c)(4)(xv) of this section. If you use paragraph (c)(4)(xv) of this section to estimate the total mass of halogen in destroyed or recaptured streams, and if the emissions from the process vent are routed through a destruction device, characterize emissions as specified in paragraph (d)(4)(iv)(A) of this section before the destruction device. Apply the destruction efficiency demonstrated for each controlled substance in the destroyed stream to that controlled substance. Exclude from the characterization halogen-containing compounds that are not controlled substances.

(C) Controlled emissions using paragraph (c)(4)(iv) of this section. If you use paragraph (c)(4)(iv) of this section to estimate the mass of halogen in destroyed or recaptured streams, and if the emissions from the process vent are routed through a destruction device, characterize the process vent's emissions monthly (or more frequently) using the monthly (or more frequent) measurements under paragraphs (d)(4)(i)(C) and (d)(4)(ii)(A) through (C) of this section. Apply the destruction efficiency demonstrated for each controlled substance in the destroyed stream to that controlled substance. Exclude from the characterization halogen-containing compounds that are not controlled substances.

(D) Emissions characterization frequency. You must repeat emission characterizations performed under paragraphs (d)(4)(iv)(A) and (B) of this section under paragraph (d)(4)(iv)(D)(1) or (2) of this section, whichever occurs first:

(1) 5-year revision. Repeat the emission characterization every 5 years. In the calculations under paragraph (c) of this section, apply the revised emission characterization to the process activity that occurs after the revision.

(2) Operating scenario change that affects the emission characterization. For planned operating scenario changes, you must estimate and compare the emission calculation factors for the changed operating scenario and for the original operating scenario whose process vent specific emission factor was measured. Use the engineering calculations and assessments specified in paragraph (c)(1)(iv) of this section. If the share of total halogen-containing compound emissions represented by any controlled substance changes under the changed operating scenario by 15 percent or more of the total, relative to the previous operating scenario (this includes the cumulative change in the emission calculation factor since the last emissions test), you must repeat the emission characterization. Perform the emission characterization before February 14 of the year that immediately follows the change. In the calculations under paragraph (c) of this section, apply the revised emission characterization to the process activity that occurs after the operating scenario change.

(E) Subsequent measurements. If a process vent with controlled substance emissions less than 0.1 metric tons, per paragraph (c)(1)(ii) of this section, is later found to have controlled substance emissions of 0.1 metric tons or greater, you must perform an emission characterization under this paragraph (d)(4)(iv)(E) during the following year.

(v) Emissions characterization: process vents emitting less than 0.1 metric tons. To characterize emissions from any process vent emitting less than 0.1 metric tons, comply with paragraphs (d)(4)(v)(A) and (B) of this section, as appropriate. Only halogen-containing reactants, products, and byproducts that occur in a stream in greater than trace concentrations must be monitored under this paragraph (d)(4)(v).

(A) Uncontrolled emissions. If emissions from the process vent are not routed through a destruction device, emission measurements must consist of sampling and analysis of emissions at the process vent or stack, sampling and analysis of emitted streams before the process vent, previous test results, provided the tests are representative of current operating conditions of the process, or bench-scale or pilot-scale test data representative of the process operating conditions.

(B) Controlled emissions using paragraph (c)(4)(xv) of this section. If you use paragraph (c)(4)(xv) of this section to estimate the total mass of halogen in destroyed or recaptured streams, and if the emissions from the process vent are routed through a destruction device, characterize emissions as specified in paragraph (d)(4)(v)(A) of this section before the destruction device. Apply the destruction efficiency demonstrated for each controlled substance in the destroyed stream to that controlled substance. Exclude from the characterization halogen-containing compounds that are not controlled substances.

(C) Controlled emissions using paragraph (c)(4)(iv) of this section. If you use paragraph (c)(4)(iv) of this section to estimate the mass of halogen in destroyed or recaptured streams, and if the emissions from the process vent are routed through a destruction device, characterize the process vent's emissions monthly (or more frequently) using the monthly (or more frequent) measurements under paragraphs (d)(4)(i)(C) and (d)(4)(ii)(A) through (C) of this section. Apply the destruction efficiency demonstrated for each controlled substance in the destroyed stream to that controlled substance. Exclude from the characterization halogen-containing compounds that are not controlled substances.

(vi) Emissions characterization: emissions not accounted for by process vent estimates. Calculate the weighted average emission characterization across the process vents before any destruction devices. Apply the weighted average emission characterization for all the process vents to any halogen emissions that are not accounted for by process vent estimates.

(vii) Impurities in reactants. If any halogen-containing impurity is fed into a process along with a reactant (or other input) in greater than trace concentrations, this impurity shall be monitored under this section and included in the calculations under paragraph (c) of this section in the same manner as reactants fed into the process, fed into the destruction device, recaptured, or emitted, except the concentration of the impurity in the mass fed into the process shall be measured, and the mass of the impurity fed into the process shall be calculated as the product of the concentration of the impurity and the mass fed into the process. The mass of the reactant fed into the process may be reduced to account for the mass of the impurity.

(viii) Alternative to error calculation. As an alternative to calculating the relative and absolute errors associated with the estimate of emissions under this paragraph (d)(4), you may comply with the precision, accuracy, and measurement and calculation frequency requirements of paragraph (d)(4)(viii)(A) through (C) of this section.

(A) Mass measurements. Measure the masses specified in paragraph (d)(4)(i) of this section using flowmeters, weigh scales, or a combination of volumetric and density measurements with accuracies and precisions of ±0.2 percent of full scale or better.

(B) Concentration measurements. Measure the concentrations specified in paragraph (d)(4)(ii) or (iii) of this section, as applicable, using analytical methods with accuracies and precisions of ±10 percent or better.

(C) Measurement and calculation frequency. Perform the mass measurements specified in paragraph (d)(4)(i) of this section and the concentration measurements specified in paragraph (d)(4)(ii) or (iii) of this section, as applicable, at least weekly, and calculate emissions at least weekly.

(5) Emission and stream testing, including analytical methods. Select and document testing and analytical methods as follows:

(i) Sampling and mass measurement for emission testing. For emission testing in process vents or at the stack, use methods for sampling, measuring volumetric flow rates, non-controlled substance gas analysis, and measuring stack gas moisture that have been validated using a scientifically sound validation protocol.

(A) Sample and velocity traverses. Acceptable methods include but are not limited to EPA Method 1 or 1A in appendix A-1 to 40 CFR part 60.

(B) Velocity and volumetric flow rates. Acceptable methods include but are not limited to EPA Method 2, 2A, 2B, 2C, 2D, 2F, or 2G in appendix A-1 to 40 CFR part 60. Alternatives that may be used for determining flow rates include Other Test Method 24 (incorporated by reference, see § 82.27) and ALT-012 (incorporated by reference, see § 82.27).

(C) Non-controlled substance gas analysis. Acceptable methods include but are not limited to EPA Method 3, 3A, or 3B in appendix A-1 to 40 CFR part 60.

(D) Stack gas moisture. Acceptable methods include but are not limited to EPA Method 4 in appendix A-1 to 40 CFR part 60.

(ii) Analytical methods. Use a quality-assured analytical measurement technology capable of detecting the analyte of interest at the concentration of interest and use a sampling and analytical procedure validated with the analyte of interest at the concentration of interest. Where calibration standards for the analyte are not available, a chemically similar surrogate may be used. Acceptable analytical measurement technologies include but are not limited to gas chromatography (GC) with an appropriate detector, infrared (IR), Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR). Acceptable methods for determining controlled substances include EPA Method 18 in appendix A-1 to 40 CFR part 60, EPA Method 320 in appendix A to 40 CFR part 63, EPA 430-R-10-003 (incorporated by reference, see § 82.27), ASTM D6348-03 (incorporated by reference, see § 82.27), or other analytical methods validated using EPA Method 301 at appendix A to 40 CFR part 63. The validation protocol may include analytical technology manufacturer specifications or recommendations.

(iii) Documentation in the monitoring plan. Describe the sampling, measurement, and analytical method(s) used under paragraphs (d)(5)(i) and (ii) of this section in the monitoring plan. Identify the methods used to obtain the samples and measurements listed under paragraphs (d)(5)(i)(A) through (D) of this section. At a minimum, include in the description of the analytical method a description of the analytical measurement equipment and procedures, quantitative estimates of the method's accuracy and precision for the analytes of interest at the concentrations of interest, as well as a description of how these accuracies and precisions were estimated, including the validation protocol used.

(6) Emission monitoring for pieces of equipment. If conducting a site-specific leak detection method or monitoring approach for pieces of equipment, each entity must follow paragraph (d)(6)(i) or (ii) of this section and follow paragraph (d)(6)(iii) of this section.

(i) Site-specific leak monitoring approach. Each entity may develop a site-specific leak monitoring approach. The entity must validate the leak monitoring method and describe the method and the validation in the monitoring plan. To validate the site-specific method, the entity may, for example, release a known rate of the controlled substances or surrogates of interest, or may compare the results of the site-specific method to those of a method that has been validated for the controlled substances or surrogates of interest. In the description of the leak detection method and its validation, include a detailed description of the method, including the procedures and equipment used and any sampling strategies. Also include the rationale behind the method, including why the method is expected to result in an unbiased estimate of emissions from equipment leaks. If the method is based on methods that are used to detect or quantify leaks or other emissions in other regulations, standards, or guidelines, identify and describe the regulations, standards, or guidelines and why their methods are applicable to emissions of controlled substances or surrogates from leaks. Account for possible sources of error in the method, e.g., instrument detection limits, measurement biases, and sampling biases. Describe validation efforts, including but not limited to any comparisons against standard leaks or concentrations, any comparisons against other methods, and their results. If using the Screening Ranges Approach, the EPA Correlation Approach, or the Unit-Specific Correlation Approach with a monitoring instrument that does not meet all of the specifications in EPA Method 21 in appendix A-7 to 40 CFR part 60, then explain how and why the monitoring instrument, as used at the facility, would nevertheless be expected to accurately detect and quantify emissions of controlled substances or surrogates from process equipment, and describe how accuracy was verified. For all methods, provide a quantitative estimate of the accuracy and precision of the method.

(ii) EPA Method 21 monitoring. If it is determined that EPA Method 21 in appendix A-7 to 40 CFR part 60 is appropriate for monitoring a controlled substance, conduct the screening value concentration measurements using EPA Method 21 to determine the screening range data or the actual screening value data for the Screening Ranges Approach, EPA Correlation Approach, or the Unit-Specific Correlation Approach. For the one-time testing to develop the Unit-Specific Correlation equations in EPA-453/R-95-017 (incorporated by reference, see § 82.27), conduct the screening value concentration measurements using EPA Method 21 and the bagging procedures to measure mass emissions. Concentration measurements of bagged samples must be conducted using gas chromatography following analytical procedures in EPA Method 18 in appendix A-1 to 40 CFR part 60 or other method according to this paragraph (d)(6). Use methane or other appropriate compound as the calibration gas.

(iii) Frequency of measurement and sampling. If estimating emissions based on monitoring of equipment, each entity must conduct monitoring at least annually. Sample at least one-third of equipment annually (except for equipment that is unsafe-to-monitor, difficult-to-monitor, insulated, or in heavy liquid service, pumps with dual mechanical seals, agitators with dual mechanical seals, pumps with no external shaft, agitators with no external shaft, pressure relief devices in gas and vapor service with an upstream rupture disk, sampling connection systems with closed-loop or closed purge systems, and pieces of equipment whose leaks are routed through a closed vent system to a destruction unit), changing the sample each year such that at the end of three years, all equipment in the process (that is not subject to the above-listed exceptions) has been monitored. If estimating emissions based on a sample of the equipment in the process, ensure that the sample is representative of the equipment in the process. If there are multiple processes that have similar types of equipment in similar service, and that perform activities on similar controlled substances (in terms of chemical composition, molecular weight, and vapor pressure) at similar pressures and concentrations, then the entity may annually sample all of the equipment in one third of these processes rather than one third of the equipment in each process.

(7) Destruction unit performance testing. If venting or otherwise feeding controlled substances into a destruction unit and apply the destruction efficiency of the device to one or more controlled substances in paragraph (c) of this section, each entity must conduct emissions testing to determine the destruction efficiency for each controlled substance to which the destruction efficiency was applied. The entity must either determine the destruction efficiency for the most-difficult-to-destroy controlled substance fed into the device (or a surrogate that is still more difficult to destroy) and apply that destruction efficiency to all the controlled substances fed into the device or alternatively determine different destruction efficiencies for different groups of controlled substances using the most-difficult-to-destroy controlled substance of each group (or a surrogate that is still more difficult to destroy).

(i) Destruction efficiency testing. Each entity must sample the inlet and outlet of the destruction unit for a minimum of three runs of 1 hour each to determine the destruction efficiency. The entity must conduct the emissions testing using the methods in paragraph (d)(5) of this section. To determine the destruction efficiency, emission testing must be conducted when operating at high loads reasonably expected to occur (i.e., representative of high total controlled substance load that will be sent to the device) and when destroying the most-difficult-to-destroy controlled substance (or a surrogate that is still more difficult to destroy) that is fed into the device from the processes subject to this section or that belongs to the group of controlled substances for which destruction efficiency is to be established. If the outlet concentration of a controlled substance that is fed into the device is below the detection limit of the method, the entity may use an outlet concentration of one-third the detection limit to estimate the destruction efficiency.

(A) For all other controlled substances that are vented to the destruction unit in any stream in more than trace concentrations, each entity must test and determine the destruction efficiency achieved for the most-difficult-to-destroy controlled substance or surrogate vented to the destruction unit. Examples of acceptable surrogates include the Class 1 compounds (ranked 1 through 34) in Appendix D, Table D-1 of “Guidance on Setting Permit Conditions and Reporting Trial Burn Results; Volume II of the Hazardous Waste Incineration Guidance Series,” January 1989, EPA Publication EPA 625/6-89/019. A copy of this publication can be obtained by contacting the Environmental Protection Agency, 1200 Pennsylvania Avenue NW., Washington, DC 20460, (202) 272-0167, https://www.epa.gov.

(B) [Reserved]

(ii) Destruction efficiency testing frequency. Each entity must conduct emissions testing to determine the destruction efficiency as provided in paragraph (d)(7)(ii)(A) or (B) of this section, whichever occurs first:

(A) Conduct an emissions test every 5 years. In the calculations under paragraph (c) of this section, apply the updated destruction efficiency to the destruction that occurs after the test.

(B) Destruction unit changes that affect the destruction efficiency. If making a change to the destruction unit that would be expected to affect the destruction efficiency, each entity must conduct an emissions test to update the destruction efficiency. Conduct the test before February 14 of the year that immediately follows the change. In the calculations under paragraph (c) of this section, apply the updated destruction efficiency to the destruction that occurs after the change to the device.

(iii) Previous testing. If an emissions test was conducted within the 5 years prior to November 12, 2024, and the emissions testing meets the requirements in paragraph (d)(7)(i) of this section, each entity may use the destruction efficiency determined during this previous emissions testing. For purposes of paragraph (d)(7)(ii)(A) of this section, the date of the previous emissions test rather than November 12, 2024, shall constitute the beginning of the 5-year re-measurement cycle.

(iv) Hazardous waste combustor testing. If a destruction unit used to destroy a controlled substance is subject to testing under subpart EEE of part 63 of this chapter or any portion of parts 260 through 270 of this chapter, each entity may apply the destruction efficiency specifically determined for controlled substances under that test if the testing meets the criteria in paragraph (d)(7)(i)(A) of this section. If the testing of the destruction efficiency under subpart EEE of part 63 was conducted more than 5 years ago, the entity may use the most recent destruction efficiency test provided that the design, operation, and maintenance of the destruction unit has not changed since the last destruction efficiency test in a manner that could affect the ability to achieve the destruction efficiency, and the hazardous waste is fed into the normal flame zone.

(8) Mass of previously produced controlled substances fed into a destruction unit. Each entity must measure the mass of each controlled substance that is fed into the destruction unit in more than trace concentrations. Such controlled substances include but are not limited to quantities that are shipped to the facility by another facility for destruction and quantities that are returned to the facility for reclamation but are found to be irretrievably contaminated and are therefore destroyed. The entity must use flowmeters, weigh scales, or a combination of volumetric and density measurements with an accuracy and precision of ±1 percent of full scale or better. If the measured mass includes more than trace concentrations of materials other than the controlled substance being destroyed, the entity must measure the concentration of the controlled substance being destroyed. The entity must multiply this concentration (mass fraction) by the mass measurement to obtain the mass of the controlled substance fed into the destruction unit.

(9) Emissions due to malfunctions of destruction unit. In their estimates of the mass of controlled substances destroyed, facilities that destroy controlled substances must account for any temporary reductions in the destruction efficiency that result from any malfunctions of the destruction unit, including periods of operation outside of the operating conditions defined in operating permit requirements and/or outside of the destruction unit's manufacturer's specifications.

(10) Emissions due to process startup, shutdown, or malfunctions. For each process listed in paragraph (b) of this section, each entity must account for emissions of controlled substance that occur at each facility as a result of startups, shutdowns, and malfunctions, either recording controlled substance emissions during these events, or documenting that these events do not result in significant controlled substance emissions. Facilities may use the calculation methods in paragraph (c)(1)(i) of this section to estimate emissions during startups, shutdowns, and malfunctions.

(11) Development of initial parameters. Initial scoping speciations, emissions testing, emission factor development, emission calculation factor development, emission characterization development, and destruction efficiency determinations must be completed by February 7, 2025, for processes and operating scenarios that operate between October 10, 2024, and November 12, 2024. For other processes and operating scenarios, initial scoping specifications, emissions testing, emission factor development, emission calculation factor development, emission characterization development, and destruction efficiency determinations must be complete by February 14 of the year following the year in which the process or operating scenario commences or recommences.

(12) Calibration for volumetric and density measurements. Calibrate all flow meters, weigh scales, and combinations of volumetric and density measures using monitoring instruments traceable to the International System of Units (SI) through the National Institute of Standards and Technology (NIST) or other recognized national measurement institute. Recalibrate all flow meters, weigh scales, and combinations of volumetric and density measures at the minimum frequency specified by the manufacturer. Use any of the following applicable flow meter test methods or the calibration procedures specified by the flow meter, weigh-scale, or other volumetric or density measure manufacturer.

(i) ASME MFC-3M-2004 Measurement of Fluid Flow in Pipes Using Orifice, Nozzle, and Venturi (incorporated by reference, see § 82.27).

(ii) ASME MFC-4M-1986 (Reaffirmed 2016) Measurement of Gas Flow by Turbine Meters (incorporated by reference, see § 82.27).

(iii) ASME-MFC-5M-1985, (Reaffirmed1994) Measurement of Liquid Flow in Closed Conduits Using Transit-Time Ultrasonic Flowmeters (incorporated by reference, see § 82.27).

(iv) ASME MFC-6M-1998 Measurement of Fluid Flow in Pipes Using Vortex Flowmeters (incorporated by reference, see § 82.27).

(v) ASME MFC-7M-1987 (Reaffirmed 1992) Measurement of Gas Flow by Means of Critical Flow Venturi Nozzles (incorporated by reference, see § 82.27).

(vi) ASME MFC-9M-1988 (Reaffirmed 2001) Measurement of Liquid Flow in Closed Conduits by Weighing Method (incorporated by reference, see § 82.27).

(vii) ASME MFC-11M-2006 Measurement of Fluid Flow by Means of Coriolis Mass Flowmeters (incorporated by reference, see § 82.27).

(viii) ASME MFC-14M-2003 Measurement of Fluid Flow Using Small Bore Precision Orifice Meters (incorporated by reference, see § 82.27).

(13) Calibration for concentration determinations. All analytical equipment used to determine the concentration of controlled substances, including but not limited to gas chromatographs and associated detectors, IR, FTIR, and NMR devices, must be calibrated at a frequency needed to support the type of analysis specified in the monitoring plan as required under paragraph (d)(5)(iii) of this section. Quality assurance samples at the concentrations of concern must be used for the calibration. Such quality assurance samples must consist of or be prepared from certified standards of the analytes of concern where available; if not available, calibration must be performed by a method specified in the monitoring plan.

(e) Data reporting requirements—(1) All facilities. In addition to the information required by § 82.13, for class I controlled substances, and § 82.24, for class II controlled substances, each entity must report the information in paragraphs (e)(1)(ii) through (iv) of this section according to the schedule in paragraph (e)(1)(i) of this section.

(i) Frequency of reporting under this paragraph (e)(1). The information in paragraphs (e)(1)(ii) through (v) of this section must be reported annually, as applicable.

(ii) Process identification. For each process listed in paragraph (b)(2) of this section, each entity must provide:

(A) A description and identification of the process listed in paragraph (b)(2) of this section.

(B) A description and number, letter, or other identifier for each process vent associated with the process. This identifier must be a consistent name reported from year to year.

(C) The type of method(s) (i.e., process-vent-specific emission factor, process-vent-specific emission calculation factor, or mass balance) and each applicable analytical approach (e.g., compliance options under paragraphs (c)(1)(i) and (d)(4) of this section) used to determine the mass emissions from each process vent associated with the process.

(D) The type of method(s) (e.g., site-specific leak monitoring approach or EPA Method 21 monitoring) and each applicable analytical approach (e.g., compliance options under paragraphs (c)(2)(i) and (d)(4) of this section) used to determine the mass emissions from equipment leaks associated with the process.

(iii) Process emissions. For each controlled substance, each entity must report the total mass in kilograms of the controlled substance emitted from the processes listed in paragraph (b)(2) of this section.

(iv) Effective destruction efficiency. For each process and controlled substance, report the effective destruction efficiency, DEeffective, calculated for that process using equation 31 to paragraph (c)(6) of this section.

(v) Monitoring plan. The monitoring plan, as specified in paragraph (f)(6) of this section, including any revisions since the prior year's submission as applicable.

(2) Reporting for emission factor and emission calculation factor approach. For processes whose emissions are determined using the emission factor approach under paragraph (c)(1)(iii) of this section or the emission calculation factor under paragraph (c)(1)(iv) of this section, each entity must report the following for each process.

(i) The identity and quantity of the process activity used to estimate emissions (e.g., tons of product produced or tons of reactant consumed) for each process vent associated with the process.

(ii) The site-specific, process-vent-specific emission factor(s) or emission calculation factor for each process vent associated with the process.

(iii) For each controlled substance, the mass emitted from each process vent associated with the process, in kilograms.

(iv) For each controlled substance, the total mass emitted from equipment leaks, in kilograms.

(3) Reporting for mass balance approach. For processes whose emissions are determined using the mass-balance approach under paragraph (c)(4) of this section, you must report the information listed in paragraphs (e)(3)(i) through (xiii) of this section for each process on an annual basis. Identify and separately report controlled substance emissions from transformation processes where the controlled substance reactants are produced at another facility. If you use an element other than a halogen in the mass-balance equation pursuant to paragraph (c)(4)(iii) of this section, substitute that element for the halogen in the reporting requirements of this paragraph (e)(3).

(i) If you calculate the relative and absolute errors under paragraph (c)(4)(i) of this section, the absolute and relative errors calculated under paragraph (c)(4)(i) of this section, as well as the data (including quantities and their accuracies and precisions) used in these calculations.

(ii) The balanced chemical equation that describes the reaction used to manufacture the controlled substance product and each controlled substance transformation product.

(iii) The mass and chemical formula of each controlled substance reactant emitted from the process in metric tons.

(iv) The mass and chemical formula of the controlled substance product emitted from the process in metric tons.

(v) The mass and chemical formula of each controlled substance byproduct emitted from the process in metric tons.

(vi) The mass and chemical formula of each controlled substance reactant that is fed into the process (metric tons).

(vii) The mass and chemical formula of each halogen-containing product produced by the process (metric tons).

(viii) If you use paragraph (c)(4)(iv) of this section to estimate the total mass of halogen in destroyed or recaptured streams, report the following.

(A) The mass and chemical formula of each halogen-containing product that is removed from the process and fed into the destruction device (metric tons).

(B) The mass and chemical formula of each halogen-containing byproduct that is removed from the process and fed into the destruction device (metric tons).

(C) The mass and chemical formula of each halogen-containing reactant that is removed from the process and fed into the destruction device (metric tons).

(D) The mass and chemical formula of each halogen-containing byproduct that is removed from the process and recaptured (metric tons).

(E) The demonstrated destruction efficiency of the destruction device for each controlled substance fed into the device from the process in greater than trace concentrations (fraction).

(ix) If you use paragraph (c)(4)(xv) of this section to estimate the total mass of halogen in destroyed or recaptured streams, report the following.

(A) The mass of halogen in each stream that is fed into the destruction device (metric tons).

(B) The mass of halogen that is recaptured (metric tons).

(C) The weighted average destruction efficiency of the destruction device calculated for each stream under paragraph (c)(4)(xvi) of this section.

(x) The fraction of the mass emitted that consists of each halogen-containing reactant.

(xi) The fraction of the mass emitted that consists of the halogen-containing product.

(xii) The fraction of the mass emitted that consists of each halogen-containing byproduct.

(xiii) The method used to estimate the total mass of halogen in destroyed or recaptured streams (specify paragraph (c)(4)(iv) or (xv) of this section).

(4) Reporting of destruction unit excess emission data. Each facility that destroys a controlled substance must report the excess emissions that result from malfunctions of the destruction unit, and these excess emissions must be reflected in the controlled substance estimates in paragraph (c)(1) of this section. Such excess emissions would occur if the destruction efficiency was reduced due to the malfunction.

(5) Reporting of destruction unit testing. By February 7, 2025, or by February 14 of the year immediately following the year in which it begins controlled substance destruction, each facility that destroys controlled substances must submit a report containing the information in paragraphs (e)(5)(i) through (iii) of this section. This report is one-time unless a change is made to the destruction unit that would be expected to affect its destruction efficiencies.

(i) Chemical identity of the controlled substance(s) used in the performance test conducted to determine destruction efficiency, including surrogates, and information on why the surrogate is sufficient to demonstrate the destruction efficiency for each controlled substance, consistent with requirements in paragraph (d)(7)(i) of this section, vented to the destruction unit.

(ii) Date of the most recent destruction unit test.

(iii) Name of all applicable Federal or State regulations that may apply to the destruction process.

(6) Reporting for destruction. Each facility that destroys controlled substances must report, separately from the controlled substance emissions reported under paragraph (e)(2) of this section, the following for each previously produced controlled substance destroyed:

(i) The mass of the controlled substance emitted from the destruction unit (kilograms).

(ii) [Reserved]

(7) Reporting of controlled substance products of incomplete combustion (PICs) of controlled substances. Each facility that destroys controlled substances must submit a one-time report by February 7, 2025, or by February 14 of the year immediately following the year in which it begins controlled substance destruction, that describes any measurements, research, or analysis that it has performed or obtained that relate to the formation of products of incomplete combustion that are controlled substances during the destruction of controlled substances. The report must include the methods and results of any measurement or modeling studies, including the products of incomplete combustion for which the exhaust stream was analyzed, as well as copies of relevant scientific papers, if available, or citations of the papers, if they are not. No new testing is required to fulfill the requirement of this paragraph (e)(7).

(f) Records that must be retained. Each entity must retain the dated records specified in paragraphs (f)(1) through (6) of this section, as applicable, and be able to provide such information to EPA within 5 business days of the date the records are requested.

(1) Process information records. (i) Identify all processes subject to this section. Include the unit identification as appropriate, the process identification reported for the process under paragraphs (e)(1)(ii)(A) through (B) of this section, and the product with which the process is associated.

(ii) Monthly and annual records, as applicable, of all analyses and calculations conducted as required under paragraph (c) of this section, including the data monitored under paragraph (d) of this section, and all information reported as required under paragraph (e) of this section.

(2) Scoping speciation. Retain records documenting the information collected under paragraph (d)(1) of this section.

(3) Emission factor and emission calculation factor method. Retain the following records for each process for which the emission factor or emission calculation factor method was used to estimate emissions.

(i) Identify all continuous process vents with emissions of controlled substances that are included in the top 25 percent of continuous process vents, and all continuous process vents in the remaining group (i.e., 75 percent of continuous process vents with lower emissions of controlled substances). Include the data and calculation used to develop the preliminary estimate of emissions for each process vent.

(ii) Identify all batch process vents.

(iii) For each vent, identify the method used to develop the factor (i.e., emission factor by emissions test or emission calculation factor).

(iv) The emissions test data and reports (see paragraph (d)(2)(v) of this section) and the calculations used to determine the process-vent-specific emission factor, including the actual process-vent-specific emission factor, the average hourly emission rate of each controlled substance from the process vent during the test and the process feed rate, process production rate, or other process activity rate during the test.

(v) The process-vent-specific emission calculation factor and the calculations used to determine the process-vent-specific emission calculation factor.

(vi) The annual process production quantity or other process activity information in the appropriate units, along with the dates and time period during which the process was operating and dates and time periods the process vents are vented to the destruction unit. As an alternative to date and time periods when process vents are vented to the destruction unit, a facility may track dates and time periods that process vents by-pass the destruction unit.

(vii) Calculations used to determine annual emissions of each controlled substance for each process and the total controlled substance emissions for all processes, i.e., total for facility.

(4) Mass-balance method. Retain the following records for each process for which the mass-balance method was used to estimate emissions. If you use an element other than a halogen in the mass-balance equation pursuant to paragraph (c)(4)(iii) of this section, substitute that element for the halogen in the recordkeeping requirements of this paragraph (f)(4).

(i) The data and calculations used to estimate the absolute and relative errors associated with use of the mass-balance approach.

(ii) The data and calculations used to estimate the mass of halogen emitted from the process.

(iii) The data and calculations used to determine the fractions of the mass emitted consisting of each reactant (FERd), product (FEP), and byproduct (FEBk), including the preliminary calculations in paragraph (c)(4)(viii)(A) of this section.

(5) Destruction efficiency testing. A facility that destroys controlled substances and reflects this destruction in paragraph (c) of this section must retain the emissions performance testing reports (including revised reports) for each destruction unit. The emissions performance testing report must contain all information and data used to derive the destruction efficiency for each controlled substance whose destruction the facility reflects in paragraph (c) of this section, as well as the key process and device conditions during the test. This information includes the following:

(i) Destruction efficiency (DE) determined for each controlled substance whose destruction the facility reflects in paragraph (c) of this section, in accordance with paragraph (d)(7)(i)(A) of this section.

(ii) Chemical identity of the controlled substance(s) used in the performance test conducted to determine destruction efficiency, including surrogates, and information on why the surrogate is sufficient to demonstrate destruction efficiency for each controlled substance, consistent with requirements in paragraph (d)(7)(i)(A) of this section, vented to the destruction unit.

(iii) Mass flow rate of the stream containing the controlled substance or surrogate into the device during the test.

(iv) Concentration (mass fraction) of each controlled substance or surrogate in the stream flowing into the device during the test.

(v) Concentration (mass fraction) of each controlled substance or surrogate at the outlet of the destruction unit during the test.

(vi) Mass flow rate at the outlet of the destruction unit during the test.

(vii) Test methods and analytical methods used to determine the mass flow rates and controlled substance (or surrogate) concentrations of the streams flowing into and out of the destruction unit during the test.

(viii) Destruction unit conditions that are normally monitored for device control, such as temperature, total mass flow rates into the device, and CO or O2 levels.

(ix) Name of all applicable Federal or State regulations that may apply to the destruction process.

(6) Equipment leak records. If the equipment is subject to paragraph (c)(2) of this section, each entity must maintain information on the number of each type of equipment, the service of each piece of equipment (gas, light liquid, heavy liquid); the concentration of each controlled substance in the stream; each piece of equipment excluded from monitoring requirement; the time period each piece of equipment was in service, and the emission calculations for each controlled substance for all processes. Depending on the equipment leak monitoring approach followed, each entity must maintain information for equipment on the associated screening data concentrations for greater than or equal to 10,000 ppmv and associated screening data concentrations for less than 10,000 ppmv; associated actual screening data concentrations; and associated screening data and leak rate data (i.e., bagging) used to develop a unit-specific correlation. If a site-specific leak detection approach was developed and followed, provide the records for monitoring events and the emissions estimation calculations, as appropriate, consistent with the approach for equipment leak emission estimation in the monitoring plan.

(7) All facilities. Dated records documenting the initial and periodic calibration of all analytical equipment used to determine the concentration of controlled substances, including but not limited to gas chromatographs, gas chromatography-mass spectrometry, gas chromatograph-electron capture detector, FTIR, and NMR devices, and all mass measurement equipment such as weigh scales, flowmeters, and volumetric and density measures used to measure the quantities reported under this section, including the industry standards or manufacturer directions used for calibration pursuant to paragraphs (d)(5), (6), (12), and (13) of this section.

(8) Controlled substance monitoring plan. A Controlled Substance Monitoring Plan must be completed by February 7, 2025, or within 120 days of the date that an entity first meets the criteria in paragraph (a) of this section.

(i) At a minimum, the monitoring plan shall include the elements listed in this paragraph (f)(8)(i) of this section.

(A) Identification of positions of responsibility (i.e., job titles) for collection of the emission data.

(B) Explanation of the processes and methods used to collect the necessary data for calculations under this section.

(C) Description of the procedures and methods that are used for quality assurance, maintenance, and repair of all continuous monitoring systems, flow meters, and other instrumentation used to provide data for the controlled substances reported under this part.

(ii) The monitoring plan may rely on references to existing corporate documents (e.g., standard operating procedures, quality assurance programs under appendix F to 40 CFR part 60 or appendix B to 40 CFR part 75, and other documents) provided that the elements required by paragraph (f)(8)(i) of this section are easily recognizable.

(iii) The owner or operator shall revise the monitoring as needed to reflect changes in production processes, monitoring instrumentation, and quality assurance procedures; or to improve procedures for the maintenance and repair of monitoring systems to reduce the frequency of monitoring equipment downtime.

[89 FR 82433, Oct. 10, 2024]