SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT
RULE 2011 - ATTACHMENTS
ATTACHMENT A - 1N PROCEDURE
ATTACHMENT B - BIAS TEST
ATTACHMENT C - QUALITY ASSURANCE AND QUALITY CONTROL PROCEDURES
ATTACHMENT D - LIST OF ACRONYMS AND ABBREVIATIONS
ATTACHMENT E - PROTOCOL FOR RULE 2011
ATTACHMENT F - SUPPLEMENTAL AND ALTERNATIVE CEMS PERFORMANCE REQUIREMENTS FOR LOW SOX CONCENTRATIONS
TABLE OF CONTENTS
ATTACHMENT A - 1N PROCEDURE
A. APPLICABILITY
B. PROCEDURE
EXAMPLES OF 1 N PROCEDURE
EXAMPLE 1
HOUR |
DATA POINT (LB/HR) |
1:00 A.M. |
30 |
2:00 A.M. |
25 |
3:00 A.M. |
32 |
4:00 A.M. |
34 |
5:00 A.M. |
Missing |
6:00 A.M. |
Missing |
7:00 A.M. |
Missing |
8:00 A.M. |
27 |
9:00 A.M. |
22 |
10:00 A.M. |
25 |
11:00 A.M. |
30 |
1:00 A.M. |
30 |
2:00 A.M. |
25 |
3:00 A.M. |
32 |
4:00 A.M. |
34 |
5:00 A.M. |
27.5 |
6:00 A.M. |
27.5 |
7:00 A.M. |
27.5 |
8:00 A.M. |
27 |
9:00 A.M. |
22 |
10:00 A.M. |
25 |
11:00 A.M. |
30 |
To fill in the missing three hours, take the data points from the 3 hours before and the 3 hours after the missing data period to determine an average emission over the 3 hours
25 + 32 + 34 + 27 + 22 + 25 average emissions = ----------------------------- = 27.5 lb/hr. 6
EXAMPLES OF 1 N PROCEDURE
EXAMPLE 2
HOUR |
DATA POINT (LB/HR) |
1:00 A.M. |
45 |
2:00 A.M. |
50 |
3:00 A.M. |
53 |
4:00 A.M. |
Missing |
5:00 A.M. |
Missing |
6:00 A.M. |
Missing |
7:00 A.M. |
58 |
8:00 A.M. |
Missing |
9:00 A.M. |
48 |
10:00 A.M. |
45 |
1:00 A.M. |
45 |
2:00 A.M. |
50 |
3:00 A.M. |
53 |
4:00 A.M. |
Missing |
5:00 A.M. |
Missing |
6:00 A.M. |
Missing |
7:00 A.M. |
58 |
8:00 A.M. |
53 |
9:00 A.M. |
48 |
10:00 A.M. |
45 |
In this example the missing data point at 8 A.M. is in the 3-hour period after the 3- hour missing datya period. We first fill the 8.A.M. slot.
58 + 48 average emissions for 8 A.M. = --------- = 53 2
The average for the three hour missing data period is:
45 + 50 + 53 + 58 + 53 + 48 average emissions = ----------------------------- = 51.2 6
(Amended February 14, 1997)
ATTACHMENT B
BIAS TEST
The bias of the data shall be determined based on the relative accuracy (RA) test data sets and the relative accuracy test audit (RATA) data sets for SOX pollutant concentration monitors, fuel gas sulfur content monitors, flow monitors, and emission rate measurement systems using the procedures outlined below.
Calculate the mean of the difference using Equation 2-1 of 40 CFR, Part 60, Appendix B, Performance Specification 2. To calculate bias for an SOX pollutant concentration monitor, "d" shall, for each paired data point, be the difference between the SOX concentration values (in ppmv) obtained from the reference method and the monitor. To calculate bias for a fuel gas sulfur content monitor, "d" shall, for each paired data point, be the difference between the fuel gas sulfur concentration values (in ppmv) obtained from the reference method and the monitor. To calculate bias for a flow monitor, "d" shall, for each paired data point, be the difference between the flow rate values (in scfh) obtained from the reference method and the monitor. To calculate bias for an emission rate measurement system, "d" shall, for each paired data point, be the difference between the emission rate values (in lb/hr) obtained from the reference method and the monitoring system.
Calculate the standard deviation, Sd, of the data set using Equation 2-2 of 40 CFR, Part 60, Appendix B, Performance Specification 2.
Calculate the confidence coefficient, cc, of the data set using Equation 2-3 of 40 CFR, Part 60, Appendix B, Performance Specification 2.
The monitor passes the bias test if it meets either of the following criteria:
a. the absolute value of the mean difference is less than |cc|.
b. the absolute value of the mean difference is less than 1 ppmv.
Alternatively, if the monitoring device fails to meet the bias test requirement, the Facility Permit holder may choose to use the bias adjustment procedure as follows:
a. If the CEMS is biased high relative to the reference method, no correction will be applied.
b. If the CEMS is biased low relative to the reference method, the data shall be corrected for bias using the following procedure:
CEMiadjusted = CEMimonitored x BAF (Eq. B-1)
where:
CEMiadjusted = Data value adjusted for bias at time i.
CEMimonitored = Data provided by the CEMS at time i.
BAF = Bias Adjustment Factor
BAF = 1 + (|d|/CEM) (Eq. B-2)
where:
d = Arithmetic mean of the difference between the CEMS and the reference method measurements during the determination of the bias.
CEM = Mean of the data values provided by the CEMS during the determination of bias.
If the bias test failed in a multi-level RA or RATA, calculate the BAF for each operating level. Apply the largest BAF obtained to correct for the CEM data output using equation B-1. The facility permit holder shall have the option to apply this adjustment to either all directly monitored data or to emission rates from the time and date of the failed bias test until the date and time of a RATA that does not show bias. These adjusted values shall be used in all forms of missing data computation, and in calculating the mass emission rate.
The BAF is unique for each CEMS. If backup CEMS is used, any BAF applied to primary CEMS shall be applied to the backup CEMS unless there are RATA data for the backup CEMS within the previous year.
If the BAF changes during a RATA, the new BAF must be applied to the emissions data from the time and date of the RATA until the time and date of the next RATA
(Amended July 12, 1996)(Amended April 9, 1999)
ATTACHMENT C
________________________________________________________________
QUALITY ASSURANCE AND QUALITY CONTROL PROCEDURES
A. Quality Control Program .............................................................................................C-1
B. Frequency of Testing ...................................................................................................C-2
Develop and implement a quality control program for the continuous emission monitoring systems and their components. As a minimum, include in each quality control program a written plan that describes in detail complete, step-by-step procedures and operations for each of the following activities :
Identify calibration error test procedures specific to the CEMS that may require variance from the procedures used during certification (for example, how the gases are to be injected, adjustments of flow rates and pressures, introduction of reference values, length of time for injection of calibration gases, steps for obtaining calibration error, determination of interferences, and when calibration adjustments should be made).
Explain how each component of the CEMS shall be adjusted to provide correct responses to calibration gases, reference values, and/or indications of interference both initially and after repairs or corrective action. Identify equations, conversion factors, assumed moisture content, and other factors affecting calibration of each CEMS.
Keep a written record of procedures, necessary to maintain the CEMS in proper operating condition and a schedule for those procedures.
Keep copies of written reports received from testing firms/laboratories of procedures and details specific to the installed CEMS that were to be used by the testing firms/laboratories for relative accuracy test audits, such as sampling and analysis methods. The testing firms/laboratories shall have received approval from the District by going through the District's laboratory approval program.
Keep a written record describing procedures that shall be used to implement the record keeping and reporting requirements.
Specific provisions of Section A-3 and A-5 above of the quality control programs shall constitute specific guidelines for facility personnel. However, facilities shall be required to take reasonable steps to monitor and assure implementation of such specific guidelines. Such reasonable steps may include periodic audits, issuance of periodic reminders, implementing training classes, discipline of employees as necessary, and other appropriate measures. Steps that a facility commits to take to monitor and assure implementation of the specific guidelines shall be set forth in the written plan and shall be the only elements of Section A-3 and A-5 that constitute enforceable requirements under the written plan, unless other program provisions are independently enforceable pursuant to other requirements of the SOx protocols or District or federal rules or regulations.
There are three situations which will result in an out-of-control period. These include failure of a calibration error test, failure of a relative accuracy test audit, and failure of a BIAS test, and are detailed in this subdivision. Data collected by a CEMS during an out-of-control period shall not be considered valid.
The frequency at which each quality assurance test must be given is as follows:
For each monitor or CEMS, perform the following assessments during each day in which the unit combusts any fuel or processes any material (hereafter referred to as a "unit operating day"), or for a monitor or a CEMS on a bypass stack/duct, during each day that emissions pass through the bypass stack or duct. These requirements are effective as of the date when the monitor or CEMS completes certification testing.
Test, record, and compute the calibration error of each SO2 pollutant concentration monitor, fuel gas sulfur content monitor, if applicable, and O2 monitor at least once on each unit operating day, or for monitors or monitoring systems on bypass stacks/ducts on each day that emissions pass through the bypass stack or duct. Conduct calibration error checks, to the extent practicable, approximately 24 hours apart. Perform the daily calibration error test according to the procedure in Chapter 2, Subdivision B, Paragraph 1, Subparagraph a, Clause ii of this Attachment.
For units with more than one span range, perform the daily calibration error test on each scale that has been used since the last calibration error test. For example, if the emissions concentration or the fuel gas sulfur content has not exceeded the low-scale span range since the previous calendar day, the calibration error test may be performed on the low-scale only. If, however, the emissions concentration or the fuel gas sulfur content has exceeded the low-scale span range since the previous calibration error test, perform the calibration error test on both the low- and high-scales.
i. Design Requirements for Calibration Error Testing of SOx Concentration Monitors, the Fuel Gas Sulfur Content Monitors, and O2 Monitors
Design and equip each SOx concentration monitor, fuel gas sulfur content monitor, and O2 monitor with a calibration gas injection port that allows a check of the entire measurement system when calibration gases are introduced. For extractive and dilution type monitors, all monitoring components exposed to the sample gas, (for example, sample lines, filters, scrubbers, conditioners, and as much of the probe as practical) are included in the measurement system. For in situ type monitors, the calibration must check against the injected gas for the performance of all electronic and optical components (for example, transmitter, receiver, analyzer).
Design and equip each pollutant concentration monitor, fuel gas sulfur content and O2 monitor to allow daily determinations of calibration error (positive or negative) at the zero-level (0 to 20 percent of each span range) and high-level (80 to 100 percent of each span range) concentrations.
ii. Calibration Error Test for SOx Concentration Monitors, Fuel Gas Sulfur Content Monitors, and O2 Monitors
Measure the calibration error of each SO2 concentration analyzer, fuel gas sulfur analyzer, and O2 monitor once each day according to the following procedures:
If any manual or automatic adjustments to the monitor settings are made, conduct the calibration error test in a way that the magnitude of the adjustments can be determined and recorded.
Perform calibration error tests at two concentrations: (1) zero-level and (2) high level. Zero level is 0 to 20 percent of each span range, and high level is 80 to 100 percent of each span range. All calibration gases used during certification tests and quality assurance and quality control activities shall be NIST/EPA approved standard reference materials (SRM), certified reference materials (CRM), or shall be certified according to "EPA Traceability Protocol for Assay and Certification of Gaseous Calibration Standards, " Septermber 1997, EPA 600/R-97/121 or any subsequent version published by EPA.
Introduce the calibration gas at the gas injection port as specified above. Operate each monitor in its normal sampling mode. For extractive and dilution type monitors, pass the audit gas through all filters, scrubbers, conditioners, and other monitor components used during normal sampling and through as much of the sampling probe as practical. For in situ type monitors, perform calibration checking on all active electronic and optical components, including the transmitter, receiver, and analyzer. Challenge the SOx concentration monitors, the fuel gas sulfur content monitors, and the O2 monitors once with each gas. Record the monitor response from the data acquisition and handling system. Use the following equation to determine the calibration error at each concentration once each day:
|R - A|
CE = x 100
(Eq. C-1)
S
Where:
CE = Percentage calibration error based on the span range
R = Reference value of zero- or high-level calibration gas introduced into the monitoring system.
A = Actual monitoring system response to the calibration gas.
S = Span range of the instrument
b. Calibration Error Testing Requirements for Stack Flow Monitors
Test, compute, and record the calibration error of each stack flow monitor at least once within every 14 calendar day period during which at anytime emissions flow through the stack; or for monitors or monitoring systems on bypass stacks or ducts, at least once within every 14 calendar day period during which at anytime emissions flow through the bypass stack or duct. Introduce a zero reference value to the transducer or transmitter. Record flow monitor output from the data acquisition and handling systems before and after any adjustments. Calculate the calibration error using the following equation :
|R - A| |
||||||
CE | = | x 100 |
|
(Eq. C-2) |
||
S |
Where:
CE = Percentage calibration error based on the span range
R = Zero reference value introduced into the transducer or transmitter.
A = Actual monitoring system response.
S = Span range of the flow monitor.
c. Interference Check for Stack Flow Monitors
Perform the daily flow monitor interference checks specified in Chapter 2, Subdivision B, Paragraph 1, Subparagraph c of this Attachment at least once per operating day (when the unit(s) operate for any part of the day).
Design Requirements for Flow Monitor Interference Checks
Design and equip each flow monitor with a means to ensure that the moisture expected to occur at the monitoring location does not interfere with the proper functioning of the flow monitoring system. Design and equip each flow monitor with a means to detect, on at least a daily basis, pluggage of each sample line and sensing port, and malfunction of each resistance temperature detector (RTD), transceiver, or equivalent.
Design and equip each differential pressure flow monitor to provide (1) an automatic, periodic backpurging (simultaneously on both sides of the probe) or equivalent method of sufficient force and frequency to keep the probe and lines sufficiently free of obstructions on at least a daily basis to prevent sensing interference, and (2) a means to detecting leaks in the system at least on a quarterly basis (a manual check is acceptable).
Design and equip each thermal flow monitor with a means to ensure on at least a daily basis that the probe remains sufficiently clean to prevent velocity sensing interference.
Design and equip each ultrasonic flow monitor with a means to ensure on at least a daily basis that the transceivers remain sufficiently clean (for example, backpurging the system) to prevent velocity sensing interference.
d. Recalibration
Adjust the calibration, at a minimum, whenever the calibration error exceeds the limits of the applicable performance specification for the NOx monitor, O2 monitor or stack flow monitor to meet such specifications. Repeat the calibration error test procedure following the adjustment or repair to demonstrate that the corrective actions were effective. Document the adjustments made.
e. Out-of-Control Period - Calibration Test
An out-of-control period occurs when the calibration error of an SO2 concentration monitor or a fuel gas sulfur content monitor exceeds 5.0 percent based upon the span range value, when the calibration error of an O2 monitor exceeds 1.0 percent O2, or when the calibration error of a flow monitor exceeds 6.0 percent based upon the span range value, which is twice the applicable specification. The out-of-control period begins with the hour of completion of the failed calibration error test and ends with the hour of completion of following an effective recalibration. Whenever the failed calibration, corrective action, and effective recalibration occur within the same hour, the hour is not out-of-control if 2 or more valid readings are obtained during that hour as required by Chapter 2, Subdivision B, Paragraph 5, Subparagraph a.
An out-of-control period also occurs whenever interference of a flow monitor is identified. The out-of-control period begins with the hour of the failed interference check and ends with the hour of completion of an interference check that is passed.
f. Data Recording
Record and tabulate all calibration error test data according to the month, day, clock-hour, and magnitude in ppm, dscfh, and percent volume. Program monitors that automatically adjust data to the calibrated corrected calibration values (for example, microprocessor control) to record either: (1) the unadjusted concentration or flow rate measured in the calibration error test prior to resetting the calibration, or (2) the magnitude of any adjustment. Record the following applicable flow monitor interference check data: (1) sample line/sensing port pluggage, and (2) malfunction of each RTD, transceiver, or equivalent.
For each CEMS, perform the following assessments once semi-annually thereafter, as specified below for the type of test. These semi-annual assessments shall be completed within six months of the end of the calendar quarter in which the CEMS was last tested for certification purposes (initial and recertification) or within three months of the end of the calendar quarter in which the District sent notice of a provisional approval for a CEMS, whichever is later. Thereafter, the semi-annual tests shall be completed within six months of the end of the calendar quarter in which the CEMS was last tested. For CEMS on bypass stacks/ducts, the assessments shall be performed once every two successive operating quarters in which the bypass stacks/ducts were operated. These tests shall be performed after the calendar quarter in which the CEMS was last tested as part of the CEMS certification, as specified below for the type of test.
Relative accuracy tests may be performed on an annual basis rather than on a semi-annual basis if the relative accuracies during the previous audit for the SOx CEMS are 7.5 percent or less.
For CEMS on any stack or duct through which no emissions have passed in two or more successive quarters, the semi-annual assessments must be performed within 14 operating days after emissions pass through the stack/duct.
Perform relative accuracy test audits and bias tests semi-annually and no less than 4 months apart for each S02 pollutant concentration monitor, fuel gas sulfur content monitor, stack gas volumetric flow rate measurement systems, and the S02 mass emission rate measurement system in accordance with Chapter 2, Subdivision B, Paragraphs 10, 11, and 12 and Attachment B of the Protocol for Proposed Rule 2011. The relative accuracy of the pollutant concentration monitor and the mass emission rate measurement system shall be less than or equal to 20.0 percent, and the relative accuracy of the stack gas volumetric flow rate measurement system shall be less than or equal to 15.0 percent. For monitors on bypass stacks/ducts, perform relative accuracy test audits once every two successive bypass operating quarters in accordance with Chapter 2, Subdivision B, Paragraphs 10, 11, and 12 and Attachment B (bias test) of the Draft Protocol for Proposed Rule 2011.
b. Out-of-Control Period - Relative Accuracy Test Audit
An out-of-control period occurs under any of the following conditions: (1) The relative accuracy of an SO2 pollutant concentration monitor, a fuel gas sulfur content monitor, or the S02 emission rate measurement system exceeds 20.0 percent; or (2) the relative accuracy of the flow rate monitor exceeds 15.0 percent. The out-of-control period begins with the hour of completion of the failed relative accuracy test audit and ends with the hour of completion of a satisfactory relative accuracy test audit.
c. Out of Control Period - BIAS Test
An out-of-control period occurs if all the following conditions are met:
i. Failure of a bias test as specified in Attachment B of this Appendix;
ii. The CEMS is biased low relative to the reference method (i.e. Bias Adjustment Factor (BAF), as determined in Attachment B of this Appendix, is greater than 1); and
iii. the Facility Permit holder does not apply the BAF to the CEMS data.
The out-of-control period begins with the hour of completion of the failed bias test audit and ends with the hour of completion of a satisfactory bias test.
All transducers and transmitters installed on stack flow monitors must be calibrated every two operating calendar quarters, in which an operating calendar quarter is any calendar quarter during which at anytime emissions flow through the stack. Calibration must be done in accordance with Executive Officer approved calibration procedures that employ materials and equipment that are NIST traceable.
When a calibration produces for a transducer and transmitter a percentage accuracy of greater than ± 1%, the Facility Permit holder shall calibrate the transducer and transmitter every calendar operating quarter until a subsequent calibration which shows a percentage accuracy of less than ± 1% is achieved. An out-of-control period occurs when the percentage accuracy exceeds ±2%. If an out-of-control period occurs, the Facility Permit holder shall take corrective measures to obtain a percentage accuracy of less than ±2% prior to performing the next RATA. The out-of-control period begins with the hour of completion of the failed calibration error test and ends with the hour of completion of following an effective recalibration. Whenever the failed calibration, corrective action, and effective recalibration occur within the same hour, the hour is not out-of-control if two or more valid data readings are obtained during that hour as required by Chapter 2, Subdivision B, Paragraph 5, Subparagraph a.
APEP Annual Permit Emission Program
API American Petroleum Institute
ASTM American Society for Testing & Materials
BACT Best Available Control Technology
bhp Brake Horsepower
bpd Barrels per Day
Btu British Thermal Unit
CEMS Continuous Emission Monitoring System
CPMS Continuous Process Monitoring System
CPU Central Processing Unit
CSCACS Central Station Compliance Advisory Computer System
DAS Data Acquisition System
DM District Method
dscfh Dry Standard Cubic Feet per Hour
FCCU Fluid Catalytic Cracking Unit
Fd Dry F Factor
FGR Flue Gas Recirculation
gpm Gallons per Minute
ICE Internal Combustion Engine
ID Inside Diameter
ISO International Standards Organization
lbmole Pound mole
LNB Low NOX Burner
MRR Monitoring, Reporting and Recordkeeping
NIST National Institute of Standards for Testing
NOX Oxides of Nitrogen
NSCR Non-Selective Catalytic Reduction
O2 Oxygen
ppmv Parts per Million Volume
ppmw Parts per Million by Weight
RAA Relative Accuracy Audit
RATA Relative Accuracy Test Audit
RECLAIM Regional Clean Air Incentives Market
RM Reference Method
RTC RECLAIM Trading Credits
RTCC Real Time Calendar/Clock
RTU Remote Terminal Unit
scfh Standard Cubic Feet per Hour
scfm Standard Cubic Feet per Minute
SCR Selective Catalytic Reduction
SDD Software Design Description
SNCR Selective Non-Catalytic Reduction
SOX Oxides of Sulfur
SRG Software/Hardware Requirement Guideline
swi Steam Water Injection
tpd Tons per day
tpy Tons per year
WAN Wide Area Network
DEFINITIONS
(A) SAMPLING INTERFACE is that portion of the monitoring system that performs one or more of the following operations: extraction, physical/chemical separation, transportation, and conditioning of a sample of the source effluent or protection of the analyzer from the hostile aspects of the sample or source environment.
(B) ANALYZERS
(i) AIR CONTAMINANT ANALYZER is that portion of the monitoring system that senses the air contaminant and generates a signal output which is a function of the concentration of that contaminant.
(ii) DILUENT ANALYZER is that portion of the monitoring system that senses the concentration of oxygen or carbon dioxide or other diluent gas as applicable, and generates a signal output which is a function of a concentration of that diluent gas.
(C) DATA RECORDER is that portion of the monitoring system that provides a permanent record of the output signals in terms of concentration units, and includes additional equipment such as a computer required to convert the original recorded value to any value required for reporting.
(A) A valid permit to construct or permit to operate pursuant to Rule 201 and/or Rule 203 has been issued; or
(B) An application for a permit to construct or permit to operate has been deemed complete by the Executive Officer; or
(C) An equipment which is exempt from permit per Rule 219 and is operating on or before (Rule Adoption date).
ATTACHMENT F
SUPPLEMENTAL AND ALTERNATIVE CEMS PERFORMANCE REQUIREMENTS FOR LOW SOX CONCENTRATIONS
Abbreviations used in this Attachment are:
- Low Level Spike Recovery/Bias Factor Determination (LLSR/BFD)
- High Level Spike Recovery/Bias Factor Determination (HLSR/BFD)
- Low Level RATA/Bias Factor Determination (LLR/BFD)
- Low Level Calibration Error (LLCE)
- Relative Accuracy Test Audit (RATA)
- Relative Accuracy (RA)
- Full Scale Span (FSS)
- National Institute of Standards Traceability (NIST)
A. Applicability of Supplemental and Alternative Performance Requirements
The Facility Permit holder electing to use (B)(8)(d)(ii), in Chapter 2 of Rule 2011, Appendix A to measure SOX concentrations that fall below 10 percent of the lowest vendor guaranteed full scale span range, shall satisfy the performance requirements as specified in Table F-1 listed below.
TABLE F-1
Alternative Performance Requirement(s)
CEMS RECLAIM Certified per SOX Protocol, Appendix A | Performance Requirements | |||
Yes or No | LLSR/BFD | HLSR/BFD | LLR/BFD | LLCE |
Yes | X | + | X | |
No | X | X | + | X |
B. Test Definitions, Performance Specifications and Test Procedures
This section explains in detail how each performance requirement is to be conducted.
Low Level Calibration Error
The low level calibration error test is defined as challenging the CEMS (from probe to monitor) with certified calibration gases at three levels in the 0-20 percent full scale span range. Since stable or certifiable cylinder gas standards (e.g. Protocol 1 or NIST traceable) may not be available at the concentrations required for this test, gas dilution systems may be used, with District approval, if they are used according to either District or EPA protocols for the verification of gas dilution systems in the field. The CEMS high level calibration gas may be diluted for the purpose of conducting the low level calibration error test.
Introduce pollutant concentrations at approximately the 20 percent, 10 percent, and 5 percent of full scale span levels through the normal CEMS calibration system. No low level calibration error shall exceed 2.5 percent of full scale span.
a. Perform a standard zero/span check; if zero or span check exceeds 2.5 percent full scale span, adjust monitor and redo zero/span check.
b. After zero/span check allow the CEMS to sample stack gas for at least 15 minutes.
c. Introduce any of the low level calibration error standards through the CEMS calibration system.
d. Read the CEMS response to the calibration gas starting no later than three system response times after introducing the calibration gas; the CEMS response shall be averaged for at least three response times and for no longer than six response times.
e. After the low level calibration error check allow the CEMS to sample stack gas for at least 15 minutes.
f. Repeat steps c through e until all three low level calibration error checks are complete.
g. Conduct post test calibration and zero checks.
Spike Recovery and Bias Factor Determinations
Spiking is defined as introducing know concentrations of the pollutant of interest and an appropriate non-reactive, non-condensable and non-soluble tracer gas from a single cylinder (Protocol 1 or NIST traceable if no Protocol 1 is available) near the probe and upstream of any sample conditioning systems, at a flow rate not to exceed 10 percent of the total sample gas flow rate. The purpose of the 10 percent limitation is to ensure that the gas matrix (water, CO2, particulates, interferences) is essentially the same as the stack gas alone. The tracer gas is monitored in real time and the ratio of the monitored concentration to the certified concentration in the cylinder is the dilution factor. The expected pollutant concentration (dilution factor times the certified pollutant concentration in the cylinder) is compared to the monitored pollutant concentration.
High Level Spike Recovery/Bias Factor Determination
The high level spike recovery/bias factor determination is used when the CEMS has not been certified per the standard RECLAIM requirements. The spiking facility/interface shall be a permanently installed part of the CEMS sample acquisition system and accessible to District staff as well as the Facility Permit holder.
The CEMS shall demonstrate a RA </= 20 percent, where the spike value is used in place of the reference method in the normal RA calculation, as described below. The bias factor, if applicable, shall also be determined according to Attachment B.
a. Spike the sample to the CEMS with a calibration standard containing the pollutant of interest and CO or other non-soluble, non-reacting alternative tracer gas (alternative tracer gas) at a flow rate not to exceed 10 percent of the CEMS sampling flow rate and of such concentrations as to produce an expected 40-80 percent of full scale span for the pollutant of interest and a quantifiable concentration of CO (or alternative tracer gas) that is at least a factor of 10 higher than expected in the unspiked stack gas. The calibration standards for both pollutant of interest and CO (or alternative tracer gas) must meet RECLAIM requirements specified in Attachment A.
b. Monitor the CO (or alternative tracer gas) using an appropriate continuous (or semi-continuous if necessary) monitor meeting the requirements of Method 100.1 and all data falling within the 10-95 percent full scale span, and preferably within 30-70 percent full scale span.
c. Alternate spiked sample gas and unspiked sample gas for a total of nine runs of spiked sample gas and ten runs of unspiked sample gas. Sampling times should be sufficiently long to mitigate response time and averaging effects.
d. For each run, the average CEMS reading must be between 40 percent full scale span and 80 percent full scale span. If not, adjust spiking as necessary and continue runs; but expected spike must represent at least 50 percent of the total pollutant value read by the CEMS.
e. Calculate the spike recovery for both the pollutant and the CO (or alternative tracer gas) for each run by first averaging the pre- and post-spike values for each run and subtracting that value from the spiked value to yield nine values for recovered spikes.
f. Using the CO (or alternative tracer gas) spike recovery values for each run and the certified CO (or alternative tracer gas) concentration, calculate the dilution ratio for each run. Multiply the certified pollutant concentration by the dilution factor for each run to determine the expected diluted pollutant concentrations. Using the expected diluted concentrations as the "reference method" value calculate the Relative Accuracy as specified in Appendix A. The RA shall be </= 20 percent. Determine the bias factor, if applicable, according to Attachment B.
Low Level Spike Recovery/Bias Factor Determination
The low level spike recovery/bias factor determination is used to determine if a significant bias exists at concentrations near the 10 percent full scale span level. The spiking facility/interface shall be a permanently installed part of the CEMS sample acquisition system and accessible to District staff as well as the Facility Permit holder.
There are no pass/fail criteria with respect to the magnitude of the percent relative accuracy. There are performance criteria for the range of concentration on the CEMS and the extent to which the spike must be greater than the background pollutant level.
a. Spike the sample to the CEMS with a calibration standard containing the pollutant of interest and CO or other non-soluble, non-reacting alternative tracer gas (alternative tracer gas) at a flow rate not to exceed 10 percent of the CEMS sampling flow rate and of such concentrations as to produce an expected 10-25 percent of full scale span for the pollutant of interest and a quantifiable concentration of CO (or alternative tracer gas) that is at least a factor of 10 higher than expected in the unspiked stack gas. The calibration standards for both pollutant of interest and CO (or alternative tracer gas) must meet RECLAIM requirements specified in Appendix A.
b. Monitor the CO (or alternative tracer gas) using an appropriate continuous (or semi-continuous if necessary) monitor meeting the requirements of Method 100.1 and all data falling within the 10-95 percent full scale span, and preferably within 30-70 percent full scale span.
c. Alternate spiked sample gas and unspiked sample gas for a total of nine runs of spiked sample gas and ten runs of unspiked sample gas. Sampling times should be sufficiently long to mitigate response time and averaging effects.
d. For each run, the average CEMS reading must be below 25 percent full scale span and > 10 percent full scale span. If not, adjust spiking as necessary and continue runs; but expected spike must represent at least 50 percent of the total pollutant value read by the CEMS.
e. Calculate the spike recovery for both the pollutant and the CO (or alternative tracer gas) for each run by first averaging the pre- and post-spike values for each run and subtracting that value from the spiked value to yield nine values for recovered spikes.
f. Using the CO (or alternative tracer gas) spike recovery values for each run and the certified CO (or alternative tracer gas) concentration, .calculate the dilution ratio for each run. Multiply the certified pollutant concentration by the dilution factor for each run to determine the expected diluted pollutant concentrations. Using the expected diluted concentrations as the "reference method" value calculate the Relative Accuracy as specified in Appendix A. If the average difference is less than the confidence coefficient then no low level bias factor is applied. If the average difference is greater than the confidence coefficient and the average expected spike is less than the average CEMS measured spike, then no low level bias factor is applied. If the average difference is greater than the confidence coefficient and the average expected spike is greater than the average CEMS measured spike, then a low level bias factor equal to the absolute value of the average difference is added to data reported at or below the 10 percent of full scale span.
Low Level RATA/Bias Factor Determination using Enhanced Reference Method 6.1
A low level RATA/bias factor determination is designed to determine if there exists a statistically significant bias at low level concentrations. It consists of nine test runs that measure the stack concentration and the CEMS concentration concurrently.
There are no pass/fail criteria with respect to the magnitude of the percent relative accuracy. There are performance criteria for the special RATA with respect to the reference method and range of concentration on the CEMS.
The reference method for the low level RATA/bias factor determination is Method 100.1
a. Perform a minimum of nine runs of low level RATA for CEMS versus the reference method at actual levels (unspiked).
b. The full scale span range for the reference method shall be such that all data falls with 10 - 95 percent of full scale span range.
c. The reference method shall meet all Method 100.1 performance criteria.
d. Calculate the average difference (d = CEMS - reference method, ppm) and confidence coefficient (cc = statistical calculated, ppm).
e. If d > 0 then the bias = 0 ppm; if d < 0 and |d| > cc then bias = d; if d < 0 and |d| < cc then bias = 0 ppm.
C. Testing Frequency
For each CEMS, perform the aforementioned performance requirements once semiannually thereafter, as specified below for the type of test. These semiannual assessments shall be completed within six months of the end of the calendar quarter in which the CEMS was last tested for certification purposes (initial and recertification) or within three months of the end of the calendar quarter in which the District sent notice of a provisional approval for a CEMS, whichever is later. Thereafter, the semiannual tests shall be completed within six months of the end of the calendar quarter in which the CEMS was last tested. For CEMS on bypass stacks/ducts, the assessments shall be performed once every two successive operating quarters in which the bypass stacks/ducts were operated. These tests shall be performed after the calendar quarter in which the CEMS was last tested as part of the CEMS certification, as specified below for the type of test.
Relative accuracy tests may be performed on an annual basis rather than on a semiannual basis if the relative accuracies during the previous audit for the SOX CEMS are 7.5 percent or less.
For CEMS on any stack or duct through which no emissions have passed in two or more successive quarters, the semiannual assessments must be performed within 14 operating days after emissions pass through the stack/duct.