(Adopted May 14,1999)
ATTACHMENTA SUPPLEMENTAL 

### AND ALTERNATIVE CEMSPERFORMANCE REQUIREMENTS A. Applicability of Supplemental andAlternative Performance Requirements The CEMS operatorwho elects (orwho may be required)to measure concentrations that fall below 10 percent of the lowest vendor guaranteed full scale span range, shall satisfy theperformance requirements as specified in TableA- 1listed below. TABLE A-1 Alternative Performance Requirement(s)

1. 

## + (plus) denotes an additional performance requirement that shall be conducted ifthe mandatory performancerequirement(s) cannotbe met. Yes No

2. Ifthe concentrationofthe CEMS is such that the specificationsfor the low level spike recoveryhias factor determination cannot be met, the Facility Permit holder shall conduct a low level RATAhias factor determination. 

### 3. Abbreviationsused in this Attachment are: x x

Low Level SpikeRecoveryA3ias Factor Determination (LLSR.5FD) High Level SpikeRecoveryA3ias Factor Determination (HLSR.5FD) Low Level RATABias Factor Determination (LLmFD) Low Level Calibration Error (LLCE) Relative Accuracy Test Audit (RATA) Relative Accuracy (RA) National Instituteof Standards Traceability PIST) 

### B. Test Definitions, Performance Specifications andTest Procedures x

This section explains in detail how each performance requirement is to be conducted. 1. Low Level Calibration Error The low level calibration error test is defined as challenging the CEMS (from probe to monitor) with certified calibration gases (e.g., NO inN2) at three levels 

## + +

Rule 218.1 

### - 1 x xRULE 218.1, ATTACHMENT A (Cont.) (Adopted May 14,1999)
in the 0-20 percent full span range. Since certified gas mixtures or standards may not be available at the concentrations required for this test, gas dilution systemsmay be used, with District approval, if they are used accordingto either District or EPA protocols as specified in Rule 218.1, 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.

a. Performance Specifications Introduce pollutant concentrations at approximately the 20 percent, 10 percent, and 5 percent of 

### 111 span levels through the normal CEMS calibration system. No low level calibration error shall exceed 2.5 percent offull scale span. b. Testing Procedures i. Perform a standard zerolspan check; if zero or span check exceeds 2.5 percent full span, adjustmonitor and redo zerolspan check. ii. After zerolspancheck allow the CEMS to sample stack gas for at least 15minutes. iii. Introduce any of the low level calibration error standards through the CEMS calibrationsystem. iv. Read the CEMS response to the calibration gas starting no later than three system response times after introducing the calibration gas; the CEMS response shallbe averaged for at least three response times and for no longer than six response times.

v. After the low level calibration error check allow the CEMS to sample stack gas for at least 15minutes. vi. Repeat steps iii through v until all three low level calibration error checks are complete. vii. Conductpost test calibration and zero checks. 2. SpikeRecoverv and Bias FactorDeterminations Spiking is defined as introducing known concentrations of the pollutant of interest (e.g., gas standard to contain a mixture ofNO and NO2 is representative ofthe ratio of NO and NO2 in stack gas) and an appropriatenon-reactive, noncondensable and non-solubletracer gas from a single cylinder (EPA Protocol as specified in Rule 218.1 or NIST traceable to 2 percent analytical accuracy if no EPA Protocol is available) near the probe and upstream of any sample conditioning systems, at a flow rate not to exceed 10percent ofthe total sample gas flow rate. The purpose of the 10percent limitation is to ensure that the gas
Rule 218.1,Attachment A 

### - 2RULE 218.1, ATTACHMENT A (Cont.) (Adopted May 14,1999) matrix (water, C02, particulates, interferences) is essentially the same as the stack gas alone. -Thetracer 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. 

### 3. High Level SpikeRecoverv1Bia.sFactorDetermination The high level spike recovery/'bias factor determination is used when it is technologically not possible to certify the CEMS per the standard Rule 218.1 requirements. The spiking facilitylinterfaceshall be a permanently installed part ofthe CEMS sample acquisition system and accessible to the Executive Officer as well asthe CEMSoperator.

a. Performance Specifications The CEMS shall demonstrate a 

### RA 

### 5 20 percent, where the spike value is used in place of the reference method in the normal 

### RA calculation, as described below. b. Testing Procedures 

### i. Spike the sampleto the CEMS with a calibration standard containing the pollutant of interest and CO or other non-soluble, non-reacting alternative tracer gas (alternativetracer 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 pollutants of interest and CO (or alternativetracer gas) must meet requirements



### .. 11. 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. iii. 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. Samplingtimes should

### be sufficientlylong to mitigate response time and averagingeffects. iv. 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 ofthe total pollutant valueread by the CEMS.

Rule 218.1, Attachment A 

### - 3

### RULE 218.1, ATTACHMENT A (Cont.) (Adopted May 14,1999) v. Calculate the spike recovery for both the pollutant and the CO (or alternative tracer gas) for each run by first averaging the pre- and postspike values for each run and subtracting that value from the spiked value to yield nine values forrecovered spikes. vi. 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. The 

### RA shall be 

### 520percent. 4. Low Level SvikeRecovew/BiasFactor Determination The low-level spike recoveryhias factor determinationis used to determine if a significant bias exists at concentrationsnear the 10 percent full scale span level. The spiking facilitylinterface shall be a permanently installed part ofthe CEMS sample acquisition system and accessible to the Executive Officer staff as well asthe CEMS operator.

a. Performance Specifications There are no passlfail criteria with respect to the magnitude of the percent relative accuracy. There are performance criteria for the range of concentration on the CEMS the extent to which the spike xust be greater than the background pollutant level. b. Testing Procedures i. Spike the sample to the CEMS with a calibrationstandard containing the pollutant of interest and CO or other non-soluble, non-reacting alternative tracer gas (alternativetracer gas) at a flow rate not to exceed 10percent 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 10higher than expected in the unspiked stack gas. The calibration standards for both pollutants of interest and CO (or alternative tracer gas) must meet Rule 218.1 requirements. ii. 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.

Rule 2 18.1,Attachment A

### - 4

-- --.---" ---.-.-.-----. - -- ------RULE 218.1, ATTACHMENT A (Cont.) (Adopted May 14,1999) iii. 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. Samplingtimes should be sufficiently long to mitigate response time and averaging effects. iv. 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 ofthe total pollutant value read by the CEMS.

v. Calculate the spike recovery for both the pollutant and the CO (or alternative tracer gas) for each run by first averaging the pre- and postspike values for each run and subtracting that value from the spiked value to yield nine values forrecovered spikes. vi. 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 Rule 218.1. 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. 5. Low Level RATA/Bias Factor Determination using Enhanced Reference Method 6.1 A low level RATAlbias 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.

a. Performance Specifications There are no passlfail 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.

Rule 2 18.1, Attachment A - 5

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### - . - - - ---RULE 218.1, ATTACHMENT A (Cont.) (Adopted May 14,1999) b. Testing Procedures The reference method for the low level RATAhias factor determination is Method 1 00.1

. i. Perform a minimum ofnine runs oflow level RATA for CEMS versus the reference method at actual levels (unspiked). ii. The full scale spanrange for the reference method shall be such that all data falls with 20 

### - 95 percent offull scale spanrange. iii. The reference method shall meet all Method 100.1 performance criteria. iv. Calculate the average difference (d =CEMS 

### - reference method, ppm) and confidence coefficient (cc =statistical calculated,ppm).

v. 

### Ifd>Othenthebias=Oppm;ifd<Oand(d(>ccthenbias=d;ifd< 0 and Id1 <ccthen bias =0 ppm. C. Testing Frequency For each CEMS, perform the aforementioned performance requirements once a year thereafter. These annual assessments shall be completed within six months of the end ofthe calendar quarter in whichthe CEMS was originally certified.

Rule 218.1, Attachment A - 6

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