# Method 301 Evaluation of Candidate Conditional Metho d s X-Ray Based Filter Method (XFM) Multi-Metals Instrumental Analyzer Procedure (Xact-IAP) Quantitative Reference Aerosol Generator (QAG)

Prepared by : Cooper Environmenta l Services, LLC 10180 SW Ni m bus Blvd Suite J6 Portland, Oregon 97223

R e v i s i o n 1
. 0 June, 2005

### Executive Summary
A new m e tal em issions m easure m ent and validati on system has recently been developed that has the po te ntia l to s i gnif i cantlyim prove our understanding of m e tal em is sions from a wide range of source categories. This system consists of:

• A continuous em ission monitoring system (Xact-CEMS)

• An instrum e ntal an alyzer procedu r e (Xact-IAP)

• A sa m p ling and analysis m easurem e n t m e thod (XFM)

• A NIST-trac eable refere nce aero s ol genera tor (Q AG) The m easurem ent com p onents of this system ar e based on collecting a re presentative sam p le of

stack gas on a chem ically reac tive f ilter (sol id sorbent) tha t traps bo th p a rticula t e an d vapor phases of m e tals, followed by non-dest ructive X-ray fluorescence (XRF) analysis using procedures consistent with ambient m easurem ents. This system is applicab le to elem ents with atom ic number ranging from 13 (Al) to 92 (U ), and can m easure Be after nondestructiv e XRF analysis if other an alytical procedures are used; it can provide detection lim its as low as 0.1 μg/dscm with 15 m i nute turn around tim e s or lower detection lim its with longer sam p ling and analysis tim es; and has demons trated accuracies bett er than five percent and precisions better than th ree p e rcent. These g e neration an d m easurement com ponents are independently traceable to NIST: the QAG th rough procedural traceability and solution standard s, while the m easurem ent methods are analytically traceable thro ugh thin film standards and NIST standard referen ce m a terials. A series of laboratory and fi eld tests have been conducted to dem onstrate that the QAG, XFM and Xact-IAP components of this new sy stem meet Method 301 acc uracy and precision requirem e nts for conditional m e thod status. E a ch of the m e t hods m e t the perform a nc e criteria outlined in the Method 301 test pla n. These criteria included the following:

• Filte r rat i os – percen t of Cr and Pb trapped on the XFM front PTFE filter. Although this criterion is not required by Method 301, high percentages assure high particle trapp i ng efficiency.

• Metal ratio s - ra tio of Pb-norm a lize d solution c oncentr ation to Pb-normaliz ed aerosol concentration. T h is criteri on is also not required by Method 301 1 but ratios close to one assure high rela tive generation, transport and sampling efficiencies for all m e tals including vapors.

• Efficiency – percent of NIST-traceable referenc e aeroso l co ncentration m easured. A high percentage assures high absolute genera tion , transpo r t a nd sam p ling ef f i ciencies.

• Bias correction factor –ratio of reference to m e as ured aerosol concentration. A value close to one indicates high m e thod accuracy.

• Precis i on – percent relative standard devi ation determ ined from sequential m easurem ents. A low percent v a lue indicates a highly precise and stable system

.
• Linearity – correlation coefficient (r) based on a regression analysis of a plot of m easured versus referen ce aero s ol concentration

.
M e thod 301 E v al. : V1. 0 Page i of xiiThese criteria and their acceptan ce v a lues are based prim arilyon those in Method 301 and were defined in the 301 validati on test plan (Appendix A). Duri ng these tests, five elem ents (As, Cd, Cr, Pb, and Hg) were spiked at con centrations ranging from blank to about 120 μg/dscm

. Al l three (QAG, XFM, an d Xact -IAP) independent approaches showed good agreem ent over this wide range of concentra tions, and all three m e thods m e t the required criter ia f o r a ll f i ve m e tals. These res u lts a r e sum m a rized in the f o llowing three tables f o r the QAG reference aerosol generator, and the XF M and Xact-IAP m easurem ent approaches. The Xact-IA P table includes re sults from all 192 Xact-IAP runs. Comparison of QAG laboratory results w i th criteria acceptance values.
C r i t er i a A c ce p t ab l e Results a Met Criteria No. Runs > 9 > 2 5 Y es Filter Ratio (% Front) > 9 8 > 9 9 Y es Metal Ratio ( S ol./Aer.) 0.9 - 1. 1 0 .9 5 - 1.01 Y e s b Ef

f i ciency (%) > 8 0 94 - 100 Y e s Precision (%) < 1 0 < 4 Y e s Linea r i ty - Corr. Coef . ( r ) > 0.85 > 0

. 9 9 Y es

a X F M a nd X a ct re su l t s f o r a l l f i v e elemen ts
b C o n f ir med w i t h inde pen den t I C P a naly s i s result s
Compariso n of XFM field tes t resu l ts w i th criteria acceptance values.
C r iter ia A cce pt able R esult s a Me t Cri t e r ia No . Ru ns >9 2 6 Y e s Bias Co rr

. Fa ctor 0.8 0

- 1.2 0 .94 - 0.97 Y e s b Pr eci s io n ( % ) < 10 < 3 Y e s Lin ear ity

- Co rr

. C o e f . ( r ) > 0.85 > 0 .9 9 Y es

a X F M r e sult s f o r a ll fiv e ele m en ts
b C o nf irme d w i th inde pe nde nt IC P a naly s is re sult s
Compariso n of Xact-I AP field tes t results w i th criteria a cceptance v a lues. C r iter ia A c c e ptable Re sults a M e t Crit eria N o . R uns > 9 1 9 2 Y es Bi as C o rr

. Fa ctor 0.80 - 1.2 1

. 00 - 1. 14 Y e s Pr eci s i o n ( % ) < 10 < 3 Y e s Li near i t y - C o r r

. C oef. ( r ) > 0

. 85 > 0 .99 Y es

a X a ct- IA P r e su l ts fo r a l l fi v e e l e m e n t s
Many m o re test runs than required by Method 30 1 were conducted, and all of the data from these runs were included in this evaluation. The QAG and XFM tables shown below include results from all 26 XFM runs. The filter and m e tal ratios listed for the QAG are high and indicate that the relative generation, transport and sam p ling efficiencies fo r all elem ents are with in the experimental accuracy of 100%. The efficiency, precision a nd linearity values for the QAG are also all well with in the accep table range. In the case of th e XFM and Xact-IAP measurem ent

M e thod 301 E v al. : V1. 0 Page ii of xiim e thods, all of the criteria were m e t and the va lues were substantially within the acceptable range, which in the case of the bias and precision were m o re restrictive in our test plan than required by Method 301. The high correlation co efficients indicate highly linear m e thods. This high de gree of line a r ity is illus t r a ted with the following four repres entative plots of the XFM and Xact-IAP m easured values vers us the independent QAG reference aerosol concentratio n during lab o ratory and field tes t s at a hazardou s waste incinerator.

M E R CURY

y = 0. 97 9x - 0. 54 2 R 2 = 0.99 3
0 50 10 0 15 0

0 5 0 1 00 15 0 Q A G Conc ( μ g/ ds cm )XactConc(μg/dscm) n = 146 CA DM I U M

y = 0.995x - 0. 134 R 2 = 0

. 9 9 5 0 50 100 150

0 5 0 100 150 QA G Conc (μg/ds c m )XFM Conc (μg/dscm) n= 26

Representa tive sca t ter plots of XF M and Xa ct-IAP measu red concentrations versus QAG reference aerosol co ncentrations during laboratory v a lidation te sts of the QAG.

Le ad

y = 0. 991x - 1. 924 R 2 = 0. 992 0 50 10 0 15 0

0 5 0 100 150 QA G Con c . (μg/ dscm )XactConc.(μg/dscm) n=19 2 Me r c u r y

y = 1. 036 x - 1.8 0 3

R 2 = 0

. 99 1 0 50 10 0 15 0

0 5 0 100 150 Q A G C o nc . ( μ g/d s c m )XFM Conc.(μg/dscm) n= 2 4

Representa tive sca t ter plots of XF M and Xa ct-IAP measu red concentrations versus QAG reference aerosol concentrations during field va lidation tests of the XFM and Xact-IAP.

The XFM and Xact-IAP are rugged and robust m e thods that are applicable to a wide range of sources and elem ents. Because these m e thods include dilution sam p ling techniques, th ey are rela tive l y in sensitive to most stack g a s characteristics (tem perature, m o isture, PM concentration, and chemistry) and can be optim i zed for specif i c stack con d itions byadjusting dilution ratios, sam p ling tim es, etc... Their range of applicability h a s been dem onstrated by results f r om these tests a s well as o t h e r labo ra tory and field tests over the past five years includ ing relative accuracy testing using both Method 29 2 and Ontario Hydro 3 referen c e m e thods. Exam ples of t h ese field validation test results are illustrated with the following two figures. The plot of lead shows a strong lin ear relationship between the X act and Method 29

M e thod 301 E v al. : V1. 0 Page iii of xiiresults up to 2,200 μg/dscm and had a relative ac curacy of 4%. The m e rcury plot shows a sim ilar strong linear relationship between the XFM and Ontario Hydro reference m e thod results at co ncentration s down to about 1 μg/dscm and had a relative accu racy of 11%.

y = 1. 058x - 5. 786 R 2 = 1. 000 0 500 1, 000 1, 500 2, 000 2, 500

0 500 1,000 1 , 500 2, 000 2, 500 M 29 Con c . ( μ g / dscm)XactConc. (μg/dscm) Lead n=11

y = 0

. 90 8x + 0. 15 2 R 2 = 0.9 6 2 0 1 2 3 4 5 6

0 246 OH Co nc. ( μ g/dscm)XFM Conc.(μg/dscm) 

### Me rc u r y n= 9

Examples of field validation test results at a munitions incinerator 4 (le ft) and at a coalfired utility boiler w i th baghouse and NO x controls 5 (right). These tests have included wet and dry incinerato rs, and wet and dry coal-fired utility boilers covering a range of controls in clud in g elec tros tatic pre c ipitators, scrubbers and NO x cata lytic reduction controls. The XFM and Xact-IAP are also consistent with am bient m easurem ent m e thods 6, 7 and applicable to m o st of the elem en ts typically m easured in th e am bient environm ent. Thus, the recomm ende d range of source categories for which the XFM and Xact-IAP ar e applicable include s f ugitiv e and du cted em issio n s such as th ose f r om hazardous, municipal, sewage and o t her incine rators; cem ent and lim e kilns; sm elters and m ills; m i neral proc essin g, plating an d boile r sour ces using co ntrol techno logies such a s bag house filtration, electrostatic precipitation, scrubbers and NO x controls. Also, this technology offers the following additional advantages:

• Significantly shorter reporting tim es (As s hort as 15 m i nutes com p ared to 3 weeks)

• Precise (<3%), accurate (better than 5%), linear (r>0.99) and verifiable results due to non-destructive analysis

• Minim a l operator requirem ents

• The m e thods are safe an d easy to us e and generate no hazardous waste. The results from these tests as well as result s from previous field tests support the following conclusions.

• The QAG ca ndidate reference aerosol generato r is independent of its application, m e t all of the required validati on criteria, and should be a pproved as a NIST-traceable reference ae rosol gene ra tor for com p lianc e and other regulatory a pplications such as initial certif ication and c ontinuing qu ality a ssu ran ce audits of multi-m e tals CEMS as well as calibration and validation of m e tal m easurem ent m e thods.

M e thod 301 E v al. : V1. 0 Page iv of xii• The XFM and Xact-IAP candidate cond ition a l methods for measuring m e tal concentrations in em issions from stationarysources m e t all of the required validation criter ia; hav e dem onstrated the i r app licab ilityto a range of source types, controls and stack conditions; and should be appr oved for general com p liance and other regulatory applications such as in itial certification and continuing quality assurance audits of m u lti-m etals CEMS, e m ission co m p liance audits, trial burns, and other regulatory applications where stack gas m e ta l em ission m easurem ents from stationary sources are required.

M e thod 301 E v al. : V1. 0 Page v of xii

### Table of Contents

Executive S u mmary ................................................................................................................. i Appendices
............................................................................................................................ vii i List of Figu res ......................................................................................................................... ix List of Abbreviations
............................................................................................................. xi 1.0 Introductio n .................................................................................................................... 1 W h at is this report about?

................................................................................................... 1 W hy are we concerned about m e tal em issions?

................................................................. 1 W hy is the current m e tals m easure m ent system inadequate?

............................................. 1 W h at is this new m e tals m easurem ent system ?

.................................................................. 2 W h at are these candidate conditional m e thods?

................................................................. 2 W hy are the XFM and Xact-IAP candidate m e thods m o re appropriate than Method 29? . 2 W hy are these m e thods important to the EPA and other stakeholders?

............................. 3 How was the perform a nce of these m e thods evaluated?

.................................................... 3 W h ere are the results presented in th is repo rt?

................................................................... 3 2.0 Approach
........................................................................................................................ 3 2.1 Overview

.................................................................................................................... 3 2.2 General Approach

...................................................................................................... 4 2.3 Method Independence

................................................................................................ 5 2.4 QAG Validation (Phase I)

.......................................................................................... 7 2.5 XFM and Xact-IAP Validation (Phase II)

............................................................... 11 2.6 Deviations from Test Plan

....................................................................................... 12 3.0 Methods
......................................................................................................................... 14 3.1 QAG Reference Aerosol Generator

......................................................................... 14 3.2 XFM Candidate Conditional Method

...................................................................... 18 3.3 Xact Instru m e ntal Analyzer Proced ure
.................................................................... 21 4.0 Calculation s .................................................................................................................. 24 4.1 Overview

.................................................................................................................. 24 4.2 List of Symbols and Term s
...................................................................................... 24 4.3 QAG Reference Aerosol Concentration

.................................................................. 26 4.4 XFM Measured Aerosol Concentration

................................................................... 27 4.5 Xact-IAP M easured Aerosol Concen tration

............................................................ 28

M e thod 301 E v al. : V1. 0 Page vi of xii4.6 Validation Com p arison Param e ters

......................................................................... 28 4.7 Other Com p arison Pa ra m e ters

................................................................................. 33 5.0 Quality Co ntrol and Assurance
.................................................................................. 35 5.1 Overview

.................................................................................................................. 35 5.2 QAG

......................................................................................................................... 35 5.3 XFM

......................................................................................................................... 37 5.4 Xact-IAP

.................................................................................................................. 38 6.0 Results and Discussion
................................................................................................. 40 6.1 Overview

.................................................................................................................. 40 6.2 QAG Validation

....................................................................................................... 40 6.3 XFM and Xact-IAP Validation Overview

............................................................... 48 6.4 XFM Validation

....................................................................................................... 50 6.5 Xact-IAP Valida tion

................................................................................................ 52 7.0 Range of Method Application
..................................................................................... 55 7.1 Overview

.................................................................................................................. 55 7.2 Criteria for Candidate Method Applicability

........................................................... 56 7.3 Key Sa m p ling and Analysis Features

...................................................................... 56 7.4 Key Em ission Characteristics

.................................................................................. 57 7.5 Filte r Trapp i ng Ef f i ciency f o r Vapor Phase Meta ls

................................................. 58 7.6 Applicable Concentration Range

............................................................................. 62 7.7 Deposit Sta b ility

....................................................................................................... 62 7.8 Moistu re
................................................................................................................... 63 7.9 Holding Tim e s
......................................................................................................... 64 7.10 Applicable Elem ents

................................................................................................ 65 7.11 Other Related Tests

.................................................................................................. 65 7.12 Applicable Source Categories

.................................................................................. 66 8.0 Conclusions and Recommendations
........................................................................... 67 9.0 Glossary
........................................................................................................................ 68 10.0 References
..................................................................................................................... 73

M e thod 301 E v al. : V1. 0 Page vii of xii

### Appendices Appendix A: Draft Test Plan for Valid ating a Reference Pro c edure for Measuring the Concentration of Metals in Eli L i lly and Company’s Hazardous Waste Incin e rato r Stack Gas Appendix B: Determ ination of Metal Em issions from Stationary Sources Using Filte rs and S o lid Sorben ts with X-Ray Fluoresce nce Analysis Appendix C: Standard Operating Procedure for Generating a Q u antitative MultiMeta ls Ref e rence Aeros o l with th e CES QAG Appendix D: Determ ination of Metal Concentra t i ons in Em issions from St ationary Sources (Instrum ental Analyzer Procedure) Appendix E: Perform a nce Specificatio ns for a Quantitativ e Reference Aero sol Generator Appendix F : Specificatio ns and Test Proce dure f o r X-Ray Fluorescence Based Multi-Metals Continuous Em issions M onitoring System s at Stationary Sources Quality Ass u rance Requ irem ents f o r X-Ray Fluorescence Bas e d Multi-Metals Continuous Em issions M onitoring System s at Stationary Sources Appendix G: QA Infor m a tion during Phase I Appendix H: QA Infor m a tion during Phase II Appendix I: Phase I Test Data Appendix J : Phase II Tes tData Appendix K Calculations Used for Method 301 Validation Tests Appendix L: Additional Data in Support of Service and Range Extension of Candidate Methods Appendix M: Related Reports Produced by Cooper Environm e n tal Services

M e thod 301 E v al. : V1. 0 Page viii of xii

### List of Figures Figure 1: Sc hem a tic f l ow diagram illustr a ti ng ke y aspects of the gene ral valida tion procedure.

............................................................................................................................... ... 5 Figure 2: Schem a tic representation of key com p onents of CES’ reference aerosol generation system

. ............................................................................................................................... ....... 6 Figure 3: F l ow diagram showing the experim e ntal arrangem e nt used to validate the Q AG reference ae rosol gene ra tor.

...................................................................................................... 8 Figure 4: Schem a tic representation of the expe rim e ntal arran g em ent used in Phase I to validate the QAG reference aerosol generator.

......................................................................... 9 Figure 5: A. Schem a tic of flow through QAG co mponents. B. Overview of the set-up of QAG co mp onents.

................................................................................................................... 15 Figure 6: Schem a tic flow diagram of the sam p ling train used in Phase I and II XFM valida tion te sts.

....................................................................................................................... 19 Figure 7: Ph otograph of the assem b led port ad ap tor, ex trac tio n assem b ly and f ilte r ho lder.

. 19 Figure 8: Ex ploded sche m a tic view of XFM f ilte r holder with f ilter casse tte.

....................... 21 Figure 9: Overview of Xact-IAP components and flow sche m a tic.

....................................... 23 Figure 10: Q AG solution m a ss loss rate during Phase I testing.

............................................ 36 Figure 11: Q AG solution m a ss loss rate during Phase II.

....................................................... 37 Figure 12: Q AG-generated and XFM- and Xact-I AP- m easured aerosol concentrations during Phase I tests

. ............................................................................................................................ 41 Figure 13: Ratio of XFM and Xact-IAP m easured m e tal concentrations to the QAG reference aerosol concentration.

............................................................................................................. 42 Figure 14: Phase I QAG linearity plots as determ ined by the XFM.

...................................... 46 Figure 15: Phase I QAG linearity plots as determ ined with the Xact-IAP

............................. 47 Figure 16: C o m p arison of the XFM and Xact-IA P m easured concentration s with the Q AGspiked flue gas concentrati ons during Phase II testing.

.......................................................... 49 Figure 17: P h ase II XFM linearity.

......................................................................................... 51 Figure 18: P h ase II Xact linearity.

.......................................................................................... 54 Figure 19. Com p arison of Hg concentrations determ ined by XFM and Ontario Hydro reference m e thod at a co al-fired power plant.

........................................................................ 60 Figure 20 P l ot of Xact-IAP concentrati on versus Reference Method 29 m easured concentratio ns showing excellent ag reem en t over two orders of m a gnitude and at concentrations in excess of 2,000 μg/dscm

. ........................................................................... 62 Figure 21. P l ot of Pb concentrations determ ined by Reference Method 29 and the Xact.

..... 63 Figure 22: C o m p arison of results from laboratory XRF analysis in July, 2002 with Xact field test results f r om May 2002 re lative accuracy tes t s at a hazardous waste incinerator

............. 63

M e thod 301 E v al. : V1. 0 Page ix of xii

### List of Tables Table 1: Overview of Phas e I validation test schedule.

.......................................................... 10 Table 2: Acceptance criteria for QAG.

................................................................................... 11 Table 3: Overview of Phas e II validation test schedule.

......................................................... 12 Table 4: Acceptance criteria for Phas e II va lida tio n of th e XFM and Xact-IAP.

.................. 12 Table 5: Comparison of surrogate an d Phase II flue gas characteristics.

............................... 14 Table 6: QAG E m ission Rates for Phase I and II.

.................................................................. 36 Table 7: Flowm e ter evaluation during Phase I.

...................................................................... 38 Table 8: Flowm e ter evaluation during Phase II.

..................................................................... 38 Table 9: Up scale and zero drift during Phase I testing.

.......................................................... 39 Table 10: E v aluation of NIST thin-film standards by the Xact-IAP.

..................................... 39 Table 11: U p scale and zero drift during Phase II testing.

....................................................... 40 Table 12: Co m p arison of Average QAG referen ce aerosol concentrations with XFM and Xact-IAP av erage m easured concen trations (μg/d s cm ).

......................................................... 42 Table 13: Le ad and chro m i um m easured on the upstream PTFE f ilter as percen t of total XFM lead and chrom i um (μg/filter).

................................................................................................ 43 Table 14: Q AG efficien cies determ ined during P h ase I laboratory tests (%).

........................ 45 Table 15: Summary of Q AG Phase I precis i on (%).

.............................................................. 45 Table 16 Summary of P h as e I QAG validation results.

.......................................................... 47 Table 17: Summary of XFM and Xact-IAP m eas ured concentrations and QAG-spiked flue gas concentrations Phase II (μg/dscm).

.................................................................................. 49 Table 18: Su mmary of XFM Phase II bias values for each m e tal tested (μg/dscm ).

............. 50 Table 19: Summary of Phase II XFM va lidation test criteria and results.

.............................. 51 Table 20: Co m p arison of Xact-IAP with QAG refe rence concentrations and bias (μg/dscm ).

............................................................................................................................... .................. 53 Table 21: Summary of Phase II Xact results.

......................................................................... 54 Table 22: C o m p arison of Xact Phase II results with proposed PS-10 criteria.

....................... 55 Table 23. List of stack conditions fo r which Xact-IAP and XFM tests h a ve been con ducted 58 Table 24. List of test con d itions and referen ces us ed to evaluate m e thod applicab ility.

........ 61 Table 25: R ecent tests o f Xact and XFM on wet and dry stacks.

........................................... 64 Table 26: X act detection lim its determ ined at Lilly’s T149 in cinerator

................................. 66

M e thod 301 E v al. : V1. 0 Page x of xii

### List of Abbreviations μg/m 3 Micro-gram s per cubic m e ter As Arsenic Cd Cad m iu m CEMS Continuous Em issions Monitoring System CES Cooper Environm ental Se rvices LLC of Portland, OR CFPP Coal Fired P o wer Plant. CFR Code of Federal Regulations. Cr Chro m i u m DAS Data Acquisition System DQO Data Quality Objectives DSCM Dry Standard Cubic Meters DSLP Dry Standard Liters Per Minute EPA United States Environm ental Protection Agency Hg Mercury HW C Hazardous Waste Combustor IAAP Iowa Arm y Ammunition Plant IAP Instrum e ntal analyzer procedure LVM Low Volatile Meta ls ( a r s enic, be ryllium , chrom i um ) M29 EPA Re ference Method 29 M301 EPA Re ference Method 301 MACT Maxim u m Achievab le Control Technology MFC Mass Flow Controller MFM Mass Flow Meter MM-CEM Multi-m etal Continuous Em ission Monitor MRI Midwest Research Inst itute, Kansas City, MO Pb Lead PS10 EPA’s proposed Perform a nce Standard 10 for multi-m e tal CEMS QA Quality Ass u rance QAG Quantita tive Aerosol Ge nerato r QC Quality Con t rol RA Relativ e Accuracy

M e thod 301 E v al. : V1. 0 Page xi of xiiRSD Relativ e Sta ndard Devia ti on (% RSD equals precision) slpm Standard Liters Per Minute SVM Sem i -volatile m e tals (ca d m i um , lead) TEAD Tooele Army Depot USAC ERL U.S. Ar m y Construction Engineering Research Library VM Volatile Me tals (m ercury ) XCEM X-ray based Continuous Em ission Monitor XFM X-ray based Filte r Me tho d XRF X-Ray Fluorescence Zn Zinc

M e thod 301 E v al. : V1. 0 Page xii of xii

### 1.0 Introduction What is this report about? This report describ e s a new m u lti- m e tals m easurem ent and valida tion s y stem . It als o presents the results of tests dem onstrating that each of the system components m e et the U. S. Environm ental Pro t ectio n Agency (EPA) Method 301 criteria for conditio nal m e thod status. The objectives of this report ar e to p r esent and discuss these r e sults in sup port of EPA’s evaluation o f this system , and obtain EPA acceptance of its com ponents as conditional m e thods. Why are we concerned about metal emissions? Air toxic m e tals have been associated with a wide range of environm ental and hum an health effects inclu d ing resp iratory disord ers, pulm ona ry disorders, and cancer. Recent findings link air toxic m e tals with in-v ivo and in -vitro inf l ammatory r e spon ses 8, 9 . As such, there is continuing concern for potential health effects of m e tal air pollutan t s inc l u d ing such metals as Sb, As, Cd, Co, Cr, Hg, Mn, Ni, Pb, and Se. The EPA is required to control em issions of toxic and hazardous air pollutants under the Clean Air Act Am endm ent s of 1990 10 . Under Sections 112(k) and 112(c) of the Clean Air Ac t, the EPA is also requ ir e d to m onitor the am bient air concentratio ns of these s p ecies to ev aluate the ef fectiv eness of its reduction strategies. F o r these reasons, the EPA has devel oped an air toxics objective that inclu d es an effort to reduce air toxic em issions and im ple m e n t are a spec if ic contro l strateg i es to r e duce air toxic exposures by 2010 11 . However, our current understa nding of m e tal em issions is relatively po or, prim arilybecause ou r curren t m easurem ent technology is inadequate. Why is the current metals me asurement system inadequate?
A m e tals emissions m easurem ent system needs to be capable of m eeting a range of practical requirem e nts in addition to m eeting such basi c requirem e nts as bei ng accurate, precise, reliable and verifiable. Top am ong practical requirem ents is th at the m easurem ents should be tim ely and r e presen tativ e ; tha tis the result s need to be availab l e with in a tim e fram e adequate for decisions (hours to days) and repr esentative of long term e m issions (m onths to years). However, the currently accepted re ference m easurem ent system consists of one m e thod capable of only infrequent periodic m easurem ents; i.e. EPA Refe rence Method 29 (Method 29).
This m e thod is considered inadequate and ina ppropriate for current applications prim arily because it is not a continuous em ission m onitori ng system (CEMS) and therefore m a y not be adequately represen tativ e of long term aver age em issions; but also b ecause of its long reporting tim es, which are typically on the order of several weeks or m o re. For example, to be effective as a quality assu ranc e to ol f o r CEMS valida tion or tr ial bu rn applic ation s , a reference m e thod m u st provide results within ho urs of the tim e of sa m p l i ng or at least by the next day so as to allow tim e for adjustm e nts pr io r to com p leting these tests. In additio n, it is felt that for som e m e tals Method 29 suffe rs from accuracy an d precision lim itations 12, 13

. Method 29 is also relatively difficult and dange rous to use, creates large quantities of

Method 301 Eval.: V1.0 Section 1.0 Introduction Page of 40 1hazardous w a ste, recovered sam p les are difficult to ship in a p o st-911 env i ronm ent, and the m e thod is costly. In addition, Method 29 is not consistent with current ambient m e tals m easure m ents and as such m o re likely to have sy stem atic biases relative to these am bient m easure m ents. Because of the above noted li m itations of Method 29, candidate altern ative m e thods are being proposed. What is this new meta ls measurement system? The currently proposed m e tals m easurem ent sy stem consists of two candidate conditional m easure m ent m e thods, a multi-m e tal CEMS and a quantitative reference aerosol generator. The m u lti-metals CEMS is not add r es sed in th is r e port. What are these candida te conditional methods? The two candidate conditional m e thods are based on collection of representative sam p les of particle and vapor phase m e tals on a reactive filter followed by m e tal determ ination using Xray fluorescence (XRF) analysis. One is a m e thod of collecting periodic sam p les by drawing stack gas through a series of filte rs contained in a seal ed filter cassette. In this X-ray based filter m e thod (XFM), particulate phase m e tals are trapp e d on a non-reactive filter while vapor phase m e tals including m e rcury ar e collected on a chem icallyreac tive f i lter or so lid s o rbent. The concentration of m e tals in the resulting filter deposits ar e non-destructively determ ined, eithe r in the f i eld or labo rato ry using XRF analysis following an alytical procedures sim ilar to those listed in EPA’s Compendium Method IO -3.3 (“Determ ination of Metals in A mbient Particulate Matter Using X-Ray Fluorescence (XRF) Spect roscopy in Com p endium of Methods for the Determ i n ation of Inorga nic Compounds in Ambient Air, EPA/625/R96/010a, June 1999.) 14 . The stack g a s concentratio n is calculated by dividing the XRFdeterm ined m e tal m a ss by the volu m e of stack ga s that pass ed through the filters. T h e other m easure m ent m e thod is an instrum e ntal analyz er procedure (IAP) based on the collection of a representative sam p le of particles and gas pha se m e tals on a reactive filter tape followed by determ inatio n of m e tals with XRF analysis (Xac t-IAP). The other component in this system is a Quantitative Aerosol Generator (QAG). The QAG genera tes a NIST-trac e a b le refe rence aerosol that can be us ed, in addition to its other applications, to challenge and evaluate th e accuracy, precision and linearity of the m easure m ent m e thods and is applicable to non-m e t al species as well as m e tal species. Why are the XFM and Xact-IAP candidate me thods more appropriate than Method 29? These candidate m e thods are m o re appropriate than Method 29 prim arilybecause of their rapid analysis turn around tim es, which can be as short as 15 m i nutes in the case of the XactIAP or two hours in the case of the XFM if a field-portable XRF analyzer is used. Not only do these m e thods m eet the required turn around tim es, but they also provide better precision and accuracy than Meth od 29 as the results repo rt ed in this d o cum e nt demonstrate, and their results can b e independently verified because th e analysis is non-destructive. In add i tion, the m e thods provide lower detection lim its, require fewer resources, are safe and easy to use, generate no hazardous w a ste and are based on well- estab lish e d EPA analysis procedures that are consistent with EPA am bient m e asurem ent m e thods.

Method 301 Eval.: V1.0 Section 1.0 Introduction Page of 40 2Why are these methods important to the EPA and other stakeholders? We currently have a poo r unders tand ing of m e tals em itted from the country’s sm oke stacks because of the absence o f m e tals CEMS, infrequent m a nual m e thod m e a s urem ents, and substantia l u n certainty in how well th ese m easurem ents represent em issions, operating conditions and assum p tions. The XFM, Xact -IAP, and QAG candidate conditional m e thods offer the EPA m o re convenient and reliable tools for m easuring and validating m e tal em issions. This should m a ke it easier for plant operators to m a ke more frequent m easure m ents, which will provide the EPA and other stakeholders with a higher level of understanding of m e tal em issions. In addition, this technology should make it easier to test and evaluate new m easurem ent and control t echnologies by reducing cost barriers and by providing m o re tim e ly results for engineering ev aluation and adjustm e nts. Also, m o re tim ely results prov ided by these candidate methods dur in g such tes t s as trial bu rn s will reduce the need for rep eating these tests du e to extens ive delays in receiving Method 29 results, which are typ i callynot available until af ter the com p letion of such tests. How was the performance of these methods evaluated? A two phased approach was used to evalua te and valida t e th e aerosol g e n e rato r and th e f ilte r based m easurem ent m e thods. Phase I was a laboratory study in which the accuracy, precision and linearity of the QAG was established and ruggedne ss test data developed for the XFM and Xact-IAP. Phase II was a field study conducted to validate the m easurem ent m e thods for applications to stack gases. In Phase II, the validated QAG wa s used to generate a reference aerosol that was spiked into stack gas, which was subsequently m easured with the XFM and the Xact-IAP. All of the valid data ge nerated during these test s were used in these m e thod evaluations, and far m o re m e asurem en ts were taken than required by Method 301. That is, no valid results were excluded in ouranalysis, even though a substantial num ber of results cou l d have been o m itted while still m eetin g Method 30 1 requirem e nts. Is this system applicable to other sources and elements? This system is applicable to m o st e m issions fr om stationary sources a nd all of the hazardous elem ents as well as all o f the elem ents m easur ed in the am bient envir onment; includ in g Be if it is m easured with other analytical me thods after non-destru ctive XRF analysis. Where are the results pr esented in th is repor t? This report presents a summary and discussion of the m e thods used and test results. The details of the m e thods and results are presente d in the appendices of this report along with field data sh eets, NIST-traceab le certifications, sample calcu lations, all un processed d a ta, etc. 

### 2.0 Approach
2.1 Overview The prim ary objectives of these tests were to validate the QAG as a reference aerosol generator an d obtain EP A condition a l m e thod acceptance for the XFM and Xact-IAP. The

Method 301 Eval.: V1.0 Section 1.0 Introduction Page of 40 3objective of this section is to describe the general approach us ed to generate the supporting data, and discuss how this approach com p ares to EPA Method 301 requirem e nts and the approach proposed in CES’ test plan (Appendix A).
2.2 General Approach Neither an appropriate refere nce m e thod nor perfor m ance audit m a terials were available to evaluate the candidate co ndition a l m e thods. As s u ch, a new approach was required to dem onstrate the precisio n and accuracy capabil ities of the can didate m e thods. Althou gh there are nu m e rous standard EPA analytical p r otocols available that are NIST-traceable, the real lim itation was in th e sam p le collection part of the sam p l i ng and analysis procedure. A key sam p ling issue in this case was the need to v e rify sam p le collection efficiencies to a precis i on an d accuracy consisten twith the pot en tial precis ion (<5%) and accuracy (<5 %) believed to be attainable w ith the candidate m e thods. A two-phase d approach was used in this c a se as schem a tically illus t r a ted in Figure 1. The first phase (Phase I) consisted of laboratory validation of CES’ QAG, wh ile Phase II was a field evaluation test of the XFM and Xact-IA P using a reference aerosol generated by the valida t ed Q AG. The f i rst step was the develop m ent of a QAG capable of em itting a reference aerosol, which could then be validat ed in the laboratory us ing independent N I STtraceable aerosol concentration m easurem ents (Phase I). The QAG, thus validated in the laboratory, was then used in the field to spik e stack gas with a reference aerosol of NISTtraceable concentration to challenge the candi date conditional m easure m ent m e thods (Phase II). The su c cess of this approach de pended on s e vera l key factors inc l u d ing:

• Independence of the NIST-traceable aeros ol g e neration process and the N I STtraceable aerosol m easurem ent m e thods.

• High level of precision f o r both the generato r and the analytical m e thod (about 2%).

• The resulting sm all bias be tween the generator and an alytical m e thod (<5%).

• The m a gnitude of the bias being on the sa m e order of m a gnitude as the expected uncertainty in the bias established through propagation of errors in both the generator and analy tical m easurements. Although under thes e co nditions, the “true” conc entration of the ge nerated aerosol was “unknown”, its con centration was kno wn at least to an accuracy com p arable to the d e gree of propagated error and independent m e thod agreem ent or m a gnitude of the bias; i.e., <5%, which is significantly better than the existi ng m e tals reference m e thod. The resulting QAG could thus be used in the fiel d with a high level of confiden ce that the generated referen c e aerosol concentration was NI ST-traceable to an accu racy of 5% or better. The general validation procedure us e d is illus t ra ted in the sc hem a tic flow diagram shown in Figure 1. As noted above, a key component of th is validation procedure was the fact that the QAG not only generated an accurate, NIST-tra ceable aerosol of known composition, but the com position of the generated aerosol was stable over periods of several days as documented with the Xact-IAP and XFM performance dur ing evaluation testing. This docum ented

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 4 of 40aerosol stab ility allowed the determ ination of prec ision th roug h the collec tion of replic ate sequential sam p les instead of collection of si m u ltaneous samples using dual sam p ling trains.

P h as e I C E S Lab or a t or y Ai r

P has e I I Li l l y S t ac k Ga s C ES A E R O SO L G E NE RA T I O N S Y S T E M

 H i gh A c c u r a c y

 H i gh P r ec i s i o n

 H i gh Lo ng t e r m S t abi l i t y

 M e a s u r ed P r e c i s i on and S t abi l i t y Xa c t XF M

Figure 1: S c hematic f l ow diagram illus t rat i ng key aspec t s of the gene ral validation procedure.

2.3 Method Independence Independence of the aerosol generation and m eas urem ent m e thods is essential to the approach used to validate the QAG and subsequently the XFM and Xact-IAP. This m e thod independenc e is schem a tically illus t r a ted in F i gur e 2. As illus t rated in th is f i gure, the Q AG generated aerosol concen trati on is traceable to NIST (Appe ndix C). In th is case, all param e ters used in th e calculation of the ae rosol concentratio n are NIST-traceab le in cluding the concentration of the standard solu tion and the rate of solution use.

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 5 of 40Figure 2: S c hematic representatio n of ke y co mponents o f CES’ reference aeros o l generation system.

The aeroso l genera tion p r ocess was e v aluated with independe nt f ilte r sam p les of the a e rosol collected by the XFM and Xact-IA P, which were subsequently analyzed by XRF using two separate X-ray spectrometers. (Appendices B and D) The XFM and Xact-IAP param e ters used to determ ine the volum e of aerosol sa m p led are NIST traceable. (Appendix G) In addition, the XRF para meters u s ed to determ ine the m a ss of m e tal in the filter d e posit are traceable to NIST (NIST SRM 1832 and 1833, and gr avim etrically NIST tr aceable thin film standards) and are independent of the aeros ol generation process. These generation and m easure m ent m e thods are clearly ind e pendent . A lthough further traceab ility or confirm i ng m easure m ents should no t be required, additi onal m easure m ents and rou t es to traceab ility were established through independent laboratory inductively coupled plasm a analysis (ICP) of

solution a nd f ilter samples as illustrated in the lower portio n of the sche m a tic illus t r a tion shown in Figure 2. The resulting indepe ndent laboratory-determ i ned elemental concentratio ns and elem ental ra tios confirm e d the standard so lution concentrations used in

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 6 of 40the QAG. In addition, selected XFM filter samples were analyzed by ICP using an independent laboratory to c onfirm the m e tal deposit m easurem ents m a de by the XRF analyzer. T h ese independent, third party m eas urem ents were also used to confirm the elem ental co ncentration s , thei r ratios and their NIST traceab il ity (See Appendix G). It should also be noted th at the XRF analyzer us ed to analy ze the XFM filter sam p les was also used in an earlier EPA PM 2. 5 speciation program in which nu m e rous “round robin” type of quality assurance tests w e re conducted and dem o nstrated comp arable results to two other independent laboratories 15

. Thus, not only are the aerosol generation and measurem ent m e thods clearly independent, but there is a reasonable degree of independent quality assurance between the X F M and Xact m eas urem e n t m e thods. In addition, since two dif f e rent Xacts were us e d in Phase I and Phase II testing (CE S and Lilly Xacts) r e quiring two different calibrations, there is a reasonable degree of independen ce of these two sets of Xact m easurem ents. As a res u lt, when th ere is a high degree of agreem ent between the generated aerosol concentration and the m easured concen tration, accuracy of both the generator and m easure m ent m e thods are sim u ltaneo u sly valida ted within th e degree of ag reem ent because of the indep e ndence of their NIST traceability. The test procedures used for this validation report were m o re rigorous and dem a nding than the procedures described in EPA Method 301. For exam ple, the Method 301-based evaluation procedures used here include addi tion al linearity requirem e nts as well as the Method 301 precis i on an d bias requ irem ents. In addition, s ubs tantially m o re m easurem ents were m a de than were required and none of the valid data was excluded f r om the data analys is. Also, because of the m u lti-elem ental na ture of the m easurem ents, inter-ele m ental ratio requirem ents were added to acceptability criteria.
2.4 QAG Validation (Phase I) The experim e ntal arrangem ent used to validat e the QAG during Phase I te sting is illustrated in the flow diagram s in Figure 3 and Figure 4 (Details of the test and QAG are discussed in Appendices A and C). The QAG co mponents are illu strated on the right side of Figure 4. It consists of a Collison- ty pe nebulizer 16 m a intained at 0°F to m i ni m i ze water vapor loss from the NIST-tra ceable spike solution during nebuliz a tion and vap o r-drop l et e quilib ration. The spiking solution was circulated throu gh a larg e so lution rese rv oir to m i nimize the im pact on solution concentration due to loss of water from e v aporat ion. The rate of QAG metal em issions was determ ined by m easuring the solution use rate in gram s per m i nute as determ ined by a NIST-traceable balance and correcting for vapor loss. Th e resulting nebulizer-produced aerosol (about 15 lpm ) passed into a settling cham ber where liquid droplets greater than about 20 μm i n diam eter sett led out of the gas flow and were returned to the solu tion reservo i r. T h e resulting size-sel ected aerosol was then in jected into a d r ying cham ber m a intained at about 300 °F where it wa s dried and diluted with about 30 to 50 lpm of clean, dry laboratory air. The dry salt and m e tal vapor co ntaining aerosol em erging from the QAG wa s diluted further with about 20 to 40 lp m of m a ke- up air. The reference aerosol total flow was about 100 to 120 lpm , and was m o nitored with a NIST-traceable m a ss flow me t e r
.

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 7 of 40Figure 3: Flow diagram show ing the experi mental arrang ement used to validate the QAG reference aero sol generator.
The QAG-g e nerated ref e rence aerosol containe d five m e tals, (As, Cd, Cr, Pb, and Hg) representing the volatile, sem i -volatile and lo w volatility m e tal categories as defined in the Hazardous Waste Combustor (HWC) Maxim u m Achievable Contro l Technology (MACT) rule 17 . Aerosol concentrations ranged from 20 to more than 120 μ g/dscm , spanning the range of their MACT e m ission lim its. This reference aerosol was directed from the QAG to the top of the Xact stilling ch amber through 2-inch diameter stainl ess steel (SS) tubing. About 99% of

the f l ow passed th rou gh the te st a pparatus and was f ilter e d prior to f l o w m easurement. Less than 1% of the ref e rence aerosol was sa m p led fromthe stilling chamber by the XactIAP (about 0.7 slpm ). During XFM testing, a lmost 40% of the sam p le flow was drawn through the XFM plenum and retu rned to the exhaus t downstream of the stilling chamber. From this subflow, about 1 lpm of the refere nce aerosol was sampled and drawn through the

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 8 of 40Figure 4: S c hematic representatio n of the ex p erimental a r rangement used in Phase I to validate the QAG referen ce aeroso l generato r. XFM f ilter c a ssette. The resulting X F M f ilters w e re ana l yzed by XRF using EPA Com p endium Method IO-3.3 for particle de posits on filters wh ile the C E S Xact-IAP autom a tically reported metal concentrations ev ery 15 m i nutes for the duration of the test. Typical test periods consisted of establishing a stable refe rence aerosol flow through the Xact-IAP stilling cham ber and out the exhaust m a nifold. The concentration of this reference aerosol was stable to within a few percent du ri ng each series o f test runs as dem onstrated by the Xact and QAG co mb ined precision, which wa s typically on the orde r of 2 to 4 %. The aerosol m e ta l concen tra t ion in the s t illi ng cham ber was sim u ltaneously sampled and m easured by both the Xact and XFM, which provided independent confirm a tion of th e QAG reference aerosol concen trations . During linearity evaluation te sts, the aerosol concentration was increased or decreased by changing the spik ing solutio n concentration. Phase I validation testing of the QAG was conducted at CES’ laboratory using spiked am bient air. During these tests, the QAG spiked five MACT m e tals (As. Cd, Cr, Pb and Hg) at five concentration levels, including a series of blank runs, w h ich were then com p ared to the m easured concentrations reported by the CES Xact-IAP and the XFM. During Phase I, a total of 26 XFM and 148 Xact runs w e re com p ared to the QAG reference concentrations (Table 1).

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 9 of 40Table 1: Summary of QAG valid ation test schedule.

Nominal QAG Conc. Date Nominal Level for

MACT Metal μ g/dscm No. of XFM Runs No of Xact Runs
Dec. 14-15, 2004 Mid2 65 12 93

Dec. 16, 2004 Mid1 50 4 13 Dec. 16, 2004 Low 20 4 12 Dec. 16, 2004 High 130 4 11 Dec. 17, 2004 Blank 0 2 19

Total Runs 26 148

The valida t ion m e trics o r crite r ia us e d to esta blish the validity of the QAG are listed below:

• Transport Effic i ency: The calculated transport efficien cy s h all be g r eater th an 80% for all elements. Since the NIST-traceable reference aeroso l concentration is totally independent from the NIST-traceable f ilter sam p ling and analysis m e thod, thi s criterion, if m e t, m i ght be considered ade quate to establish an acceptable efficiency correction factor for the QAG.

• Lead and Cr Filter Ratios: To ensu re tha t the f i lte rs had adequate particulate trapp i ng ef f i ciency, less than two per cent of the P b and Cr were perm itted on the XFM reactive filte r downstream of the PTFE filter. This p l u s the assum e d low volatility of these e l em ents will assu re a ne a r 10 0% sam p le train trapp i n g ef f i ciency f o r these e l e m ents. This criter ion plus the f o llo wing criter ion provide a ddition a l assurance th at the trapp i ng efficiencies for all of the elem ents are near 100 %.

• Elementa l Ratios: As, Cd, Cr, and Hg concentration ratios to lead m easured in the aerosol sample m u st be within ±10% of th e con centr ation ra tios in the Q AG solution

. Meeting this criterion assures not only high trapping efficiencies but also high generation and transpo r t efficiencies fo r all of the elem ents in cluding vo la tile elem ents.

• Precis i on: The QAG must have a pr ecision, as m easured by pe rcent relative standard deviation (P RSD), of less than 10% f o r each of th e elem ents. This high precis ion criterion will enable sequential sam p ling of the candidate m e thods at each concentration level.

• Linearity: The QAG a nd both candidate filter-ba sed conditional m e thods shall have a correlation coefficient (r) that is grea ter than 0.85. This cr iterion shows that the QAG is linear over a wide ra nge of concentrations. These criteria and their acceptab l e ranges are su mmarized in Table 2.

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 10 of 40Table 2: Acceptance criteria for QAG.

Criteria Measure No. Runs Acceptable Range F back to f C r , PB ) i l t e r R a ti o r o n t ra t i o ( >9 <0. 02 Met a l Ra tio so lu tion t o aero so l ratio >9 0

. 9 t o 1

. 1 t-statistic >9 < c r or i t i c a l v a lu e Efficiency efficiency factor B >9 e t w e e n 0

. 8 a n d 1

. 0 Precision p e r c
. c e n t of spi k ed c o n >9 <10 % L i neari t y correlation coe ffi c i e n t > 9 > 0

. 8 5
h e s e c r i t e r i a i n c l u d e required b i as (efficien cy) and precision validation param e ters from o r s

h e r

2.5 XFM and Xact-IAP Validation (Phase II) The prim ary objective of Phase II tes ting wa s to valida t e th e XFM and Xact- I AP while y

Following Phase I testing, the QAG was insta lled at a hazardous waste incinerator 18 and a s

I
I A P T Method 301 (bias o r in th is case efficiency and precision ) and addition a l v a l i d a t i o n i n d i c a t relev a nt to these spec if ic tes t s: i.e., f ilter r a tio, m e tal ratio an d linea rity cr ite ria. The acceptabilityranges listed in Table 2 we re guided b y v a l u e s r e qu i r e d b y M e t h o d 3 0 1 , Perform a nce Specifications 11 and proposed Pe rform a n c e S p e c i f i c a t i o n 1 0 , a n d a r e e i t equal to thos e lis ted in th ese proc edures or are m o re res t rictive.

sam p ling flue gas. The validity of these sa m p ling and analysis m e t h o d s w a s e v a l u a t e d b com p aring the Phase I validated QAG referen ce aerosol concentration with the XFM and Xact-IAP measured con centration s
. It is im portant to note that a different Xact instrum e n t was used in Phase II than was used in Phase I.

series of validation tests we re conducted. During these tests, t h e Q A G r e f e r e n c e a e r o s o l w a spiked into incinerator flue gas at four diffe r e n t c o n c e n t r a t i o n l e v e l s w h i l e a n X F M s a m p l i n g train and Xact-IAP were collec ting simultaneous sam p les from the Xact s tilling ch amber. The experim e ntal arrang em ent was sim ilar to th at used in the laboratory w ith the prim ary difference th at the reference aero s ol was spiked i n t o s t a c k g a s i n s t e a d o f l ab o r a t o ry a i r
. I n addition, the Xact used in these field tests was different from t h e o n e u s e d d u r i n g t h e P h a s e tests at CES’ laboratory. During Phase II, the QAG spiked five MACT m e tals at four concentration levels (Table 3) into about 35 slpm of flue gas while t h e X F M a n d X a c t

concurrently sam p led the reference aerosol spiked stack gas. A total of 24 XFM and 192 Xact-IAP runs were completed during Phase II tests while the QAG was operating.

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 11 of 40Table 3: Overview of Phase II validation test schedule. Nomin a l QAG Co nc. Da te Nomin a l Lev e l μ g/dscm No . of X F M Runs No o f X a c t Runs

M a rch 4

- 5 , 20 05 Hi g h 10 8 12 45

M a rch 6, 2 0 0 5 Lo w 21 4 46 M a rch 7, 2 0 0 5 M i d 45 4 37 M a rch 8, 2 0 0 5 B l ank 0 4 64

T o t a l R uns 24 19 2
Validation criteria used to evaluate th e accep ta nce of the XFM and Xact-IAP were sim ilar to those used f o r the QAG in Phase I and are list ed in Table 4. These criteria include bias, precis i on an d linearity o f the m easurem ent m e thods. The main difference was the om ission of the filter and elem ental ratio criteria, which w e re not relev a nt to Phas e II testing. As was the cas e in P h ase I, th e acceptab i lity ranges li s t ed in Table 4 were guided by values required by Method 301, Performance Specifications 11 18 and proposed Perform a nce Specification 10 20 , and are either equal to those listed in th ese p r ocedures or are m o re restrictive. Table 4: Acceptance criteria fo r Phase II validation of th e XFM and Xact-IAP.
C r i t e r i a M e a s u r e N o . Measurements Acceptable Range
t-statistic >9 < critic al va lue or Bias correction factor >9 Between 0.8 and 1.2 Precis i on percent of em ission lim i t >9 <10% Linearity correlation coefficient >9 > 0.85

2.6 Deviations from Test Plan The original draft Test P l an was developed in the fall of 2004 to orga nize validation testing of the XFM and can be found in Appendix A. During actual testi ng, there were five significant deviations from this test plan. W hy these deviatio ns occurred and any potential im pacts to the resulting data set are discussed b e low.

• Evaluation of the Xact-IAP: The test plan proposed an approach for validating the QAG and XFM, but it did not focus on the Xact-IAP as a separate Instrum e ntal Analyzer Procedure. Following discussions withthe EPA, the scope of th e tes twas expanded to include the Xact-IAP, following th e sam e validation c r iteria as the XFM. Both the XFM and the X act-IAP are candida te co ndition a l m e thods, but th e Xact-IAP offers end-users m o re immediate feedback. For this reason, and since the sam e QAG data set could be applied to both approach es, the test plan was expanded to include validation procedures for the Xact-IA P.

• Total Capture: The original test plan proposed using a total capture approach to validate the QAG in Pha s e I. The total cap ture approach, however, was technically

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 12 of 40problem atic and was not used during the validation tests. Instead, the app r oach used was based on independent m easurem ents of the resulting Q AG generated aerosol concentration as described above.

• Blank Runs: The orig in al te st plan c a lled f o r in jection of water for blank runs to determ ine XFM detec tio n lim its. During the cou r se of testing, it was de ter m ined that pure water would freeze in the QAG. For this reason, blank 5% nitric acid was spiked instead of water. These blank tests were conducted during both Phase I (five hours) and II (eight hours). This blank testing resu lted in six XFM and about 100 Xact blank test runs. Although all five m e tals reporte d blank concentrations of less than one μ g/dscm for the XFM and the Xact-IAP, actual detection lim its were calculated using a m u ch larger data set (Appendix K) and then com p ared to the blank run s as discussed in Section 7.11.2.

• Precis i on: The precisions m easured for the QAG, XFM, an d Xact-IAP were based on the PRSD of the m easured m e tal concen trations when the QAG was spiking at a constan tra te . The origin al te st plan called for calculation of precision as a percent of the em ission lim it, and th e results indicate that calculating precision in this m a nner would have m e t the test plan precision cr iteria of 10%. However, since a range of concentrations were used to determ ine lin earity, a m o re de mandi ng protocol using all of the data including the lowest spiked c oncentrations was used that divided the standard d e v i ation at each concentration by the m ean concen tration at eachspiked level. This latter approach is cons istent with Method 301: Equation 301-6 22

.

• Flue Gas Composit ion: Phase II s a mples were collected wh en the in cinerator was burning natural gas instead of waste. In the week prior to Phase II testing, cracks were observed in a section of incine rator piping that is exposed to pressures of more than 1000 PSI. These cracks precluded the burning of waste during testing and, since it was a two to three m onth delay before the pipes could be repair ed, it was decided to conduct the tests using natural gas rather than delay the tests. A com p arison of the flue gas characteris tics fo r Phase II tests relative to flue gas ch aracteristics during surrogate feed stock burns conducted in the Fall of 2004 is shown in Table 5. In general, the incinerator em issions produ ced while burning natu ral gas in Ph ase II were very sim ilar to those observed during the surrogate feed stock burns. Most m a jor flue gas species such as SO 2 , H 2 O, CO, and CO 2 , were found in the sam e or higher concentrations during Phase II tests than in the surrogate feed stock burn tests in the fall of 2004. The prim ary difference was a decrease of 64% in particulate concentrations during Phase II tests. Howe ver, the im pact of this param e te r is insignificant at these con centration s (less th an 10 mg/dcsm @ 7% O 2 ), and would not be significant unless it were well over the p e rmitted PM emission lim its.

M e thod 301 E v al. : V1. 0 Section 2.0 Approach Page 13 of 40Table 5: Comparison of surrogate and Phase II flue gas characteristics.
Chemic a l

Species Surroga t e Test s Fa ll 200 4 Phase II M a rch 2 005 Phase II Surroga t e Ra tio

SO 2 , dry ( p

p m ) N D ± N D N D ± N D

-- -- -- -- - - HCl, dry ( p

p m ) 2. 3 ± 1. 2 1. 9 ± 0. 6 0. 8
CO 2 , dry ( % ) 8. 3 ± 0. 7 6. 0 ± 0. 1 0. 7 CO, dr y ( p

pm ) 8. 4 ± 1. 9 13

. 8 ± 0. 7 1. 7
O 2 , dry ( % ) 9. 1 ± 0. 9 11

. 4 ± 0. 1 1. 3
H 2 O ( %) 9. 2 ± 3. 3 10

. 1 ± 0. 4 1. 1
PM @ 7% O 2

(mg/ds cm) 9. 8 ± 2. 8 3. 5 ± 0. 4 0. 4

NO x , dry (

p

pm ) 40

. 5 ± 10

. 0 10 8. 1 ± 5. 5 2. 7 Flow ( dsc f

m

) 14 1 9 6 ± 10 9 6 99 5 2 ± 42 3 0. 7



### 3.0 Methods
3.1 QAG Reference Aerosol Generator The reference aeroso l us ed in these tests wa s generated with CES’ quantitative aerosol generator (Q AG). This aerosol was the prim ary reference sou r ce used to d e term ine bias and precision capabilities of the candidate condi tional m u lti-m e tals m e thods. The QAG pr ovides a continuous reference aerosol whose analyt e concentration is NIST-traceable with docum ented accuracy an d precision. Once validated in the laboratory du ring Phase I testing, the QAG wa s used to spike incinerator stack gas in the field during Phase II testing. Although the QAG has the ability to generate a w i de range of analyte-containing aerosols, the only type used in the experi m e nts described in this report were m e tal containing aerosols. The QAG g e nerates its reference aerosol using the following three basic steps:

• First, an aerosol of analyte soluti on droplets is created using a nebulizer 16

.
• This is followed by the separation and recirc ulation of large droplets using a settling cham ber where th e large droplets are rem oved while liquid and vapor phases are equilibrated.

• The third step consists of drying drop lets sm aller than 20μm in diam eter.

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 14 of 40The dried analyte-containing aerosol em issi on rate is calculated from the analyte concentration in the nebulized solution, the solution droplet em ission rate, and the total volum e of nebulizing, drying and dilution gas used to create the resultin g aerosol. Use of nebulizers to generate quantitative aerosols is ty pically lim ited by three key factors:

• The m a gnitude and uncertainty of the water vapor em ission rate lo st during droplet generation and equilibration

• Changing solution concentration due to evaporation of solution

• Generation of large dro p lets, which can rep r esen t a sign if ica n t f r action o f the em itted m a ss and could have low transport efficiency d u e to the large size of th e resulting dried sa lt p a rticles. These poten tial problems have been effectively e ithe r elim inated or m i nim i zed in the curren t model of the QAG by (1) generating the droplet ae rosol at 32° F using cooled water-saturated nebulizing air to m i nim i ze and quantify the evap orative component, (2) using a large solution reservoir to both m i ni m i ze the im pac tof changi ng concentration due to evaporation and to allow f o r m e asurem ent of total so lution use rate, and 3) incorporation of a stilling cha mber to separate and recycle large solution droplets. Key QAG c o m ponents are illustrated with the schem a tic drawings shown in Figure 5.

A. B. Figure 5: A. Schematic of flow through QA G components. B. Overview of the set-up of QAG comp onents.

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 15 of 40There are six m a jor components of the QAG:

• A ref e rence solution con t rol com ponent is us ed to circu l ate the analy t e-contain i ng solution through the nebulizer and measur e the total solution use rate. This com ponent consists of a peristaltic pum p, solution reservoir, balance, connecting tubing and a laptop used to record the balance reading every 15 seconds.

• A nebulizer air control com ponent used to m a intain and m easure the flow, tem p erature, pressure an d sa turation of air used in the nebulization process. This com ponent uses com p ressed air at about 20 PSI-gage pressure to force air through the nebulizer. T h e nebulizing air passes through fl ow and pressure regulators, an external bubbler to saturate the air at room temper ature and then a second bubbler to assure that the neb u liz ing air is satura ted a 32° F prior to entering the nebulizer.

• A tem p erature control component (ice bath) is used to control the tem p erature of the nebulizer air, the nebulizer and the settling/equilibrating chamber at 32° F.

• A Collison- type nebulize r 16 com ponent is used to create the solution droplet aerosol. It consists of three m a jor com ponents: th e nebulizer cup, the nebulizer and nebulizer nozzle as describe in m o re detail in Appe ndix C. The nebulizer cup contains the standard solution. This solution is continuous ly circulated from the nebulizer cup to an external reservoir to m i ni m i ze the im p act of vapor loss on solution concentration and to allow for determ ination of the solution use rate.

• A settling/equilib rating cham ber component located ju st abo v e the nebu lizer com ponent. The nebulizer-generated aerosol is directed into this cham ber where large droplets settle from the gas stream and the rem a ining droplets equilibrate with water vapor prior to entering the drying cham ber. The ne bulization process creates a droplet spray containing a wide range of dr oplet sizes. The largest d r oplets im pact o n the walls of the nebulizer cup and are recycl ed. The sm aller droplets are entrained in the nebulize r air f l ow an d pass into the se ttling

- e quilib ration cham ber. The f unction of

the settlin g-equilibr a tion cham ber is to r e m ove and recycle all d r oplets greater th an about 20 μm in diam eter as well as to a ssure d r oplet-vapo r equ ilib rium at 32°F. Thus, the on ly droplets e m itted into the drying ch am ber have diam eters le ss than 20 μm and have been equilibrated with water vapor at 32°F.

• A drying cham ber com p onent with tem p erature and flow cont rols. In this cham ber, the size-restricted and vapor equilibrate d aerosol from the settling/equilibrating cham ber is surrounded by dry air at about 300° F, which is used to dry the reference solution droplets prior to being em itted fro m the QAG. The aerosol exiting the drying cham ber consists of the transport ga s (air), water and m e tal vapor and dried salt p a rticles

. The size o f the salt p a rtic les is controlled by the analyte solu tion concentration, the design of th e settling cham ber and the flow rate of nebulizer air. This aerosol is the reference aerosol pr oduced by the QAG. However, in this experim e nt, the aerosol was further diluted with m a keup air prior to bein g transpo r te d to the Xac ts tilling ch amber f r om wh ich both Xact-IAP and XFM sam p les were drawn. QAG efficiencies referred to in this report are com b ination generation

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 16 of 40(aerosol em itted from the drying chamber of the QAG) and transport to the Xact stilling chamber. The QAG’s generated aero sol concentration ( ) is process traceable to NIST through the traceab ility of its co mponent s (see Appendix C). As de monstrated in Equation 1 b e low, the generated concentration is a function of the solution st an dard concen tr ation of the ( ), to tal f l ow rate ( F a-QAG i C

s-QAG i C t ), rate of m a ss loss of the solution ( R m ), and rate of vapor loss ( R v ). Proces s traceability to NIST is estab lis hed by using ins t rum e nts that are NIST-traceable (e.g., calibrated with NIS T standards) to m easur e these parameters and a solution with NISTtraceable co ncentration s
. The final product of the QAG is an aerosol cont aining dried salt particles and vapors of the analyte or analytes. The concentration of the an alytes in th e aerosol and the concentration uncertainty are calculated fro m the QAG’s reco rded operating param e ters. The equation for calculating the generated aerosol con centr ation is as f o llows:



### ) R (R F C C v m t QAG s i QAG a i 

### − = −

− Equation 1

Where:
a-QAG i C = Concentration of the i th elem ent in the reference aerosol generated by the QAG
s-QAG i C = Concentration of the i th elem ent in the QAG’s NIST-traceable solution F

t = Total com b ined flow of the nebulizer air, drying air and m a keup air or stack gas R m = Total rate of solution m a ss loss for the QAG, determ ined fro m the slope of a linear least sq uares fit of the rese rvoir m a ss data over the period of a test or series of tests R v = Rate of vapor loss from the refe rence solution, as calculated using the f o llowin g equation : 

### ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

− =

c e v e v 

### P P 1 M F R Equation 2

Where: F

e = Flow of exp a nded nebul izer air in the QAG M v = Mass of water vapor in a liter of saturated air at 32°F

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 17 of 40P e = Absolute pressure of the expanded nebulizer air (atm ospheric) P c = Absolute pressure of the com p ressed nebulizer air
Uncerta inty in the gen e r a ted r e f e ren ce aero s ol c oncentr ation was determ ined using standard propagation of error techniques re levant to the param e ters used in Equation 1 and Equation 2 (See Appendix C). The estim ated un certainties f o r these p a ra m e ters durin g Phase I an d II testing are 0.5% for , 3% for F s-QAG i C e , 1.5% for F t , 7% for M v , 3% for P c , 1% for P e , and 1% for R m . The s e uncertainty values are based on equipm ent m a nufacturer c e rtif ications, NIST and/or engineering estimates of nebulization/equilibration temp eratu r e uncertainties. Using these uncertainties, th e p r opagated u n certainty d u ring Phase I and II testing was calculated to be about 4% for an aerosol concentration ( ) of about 70 μg/m a-QAG i C 3

. 3.2 XFM Candidate Conditional Method The current reference m e thod for m e asuring m e ta l em issions from stationary point sources (Method 29) is based on 30 year old probe, filterand im pinger type sam p ling trains. T h is m e thod is difficult and d a ngerous to use, crea tes large qu antities of hazard ous waste, recovered samples are difficult to ship, and seve ral weeks are required for an analysis to be com p leted. The XFM candidate con d ition a l m e thod summarized in this s ubsection an d described in detail in Appendi x B is based on a safe, easy to use sam p ling train that traps both PM and vapor phase m e tals on stacked filters that a field engineer never touches and can easily be either analyzed by XRF in the field or express m a iled to a laboratory for 24 hour turn around tim es. Although the XFM procedur e has been optim ized for MACT m e t a l analytes, it is applicable to elem ents with atom ic num b er ranging from 13 (Al) to 92 (U). The sam p ling train used for these Method 301 va lidation tests is shown schem a tically in Figure 6. It is com posed of five m a jor subcom ponents:

• Extrac tion- s tilling ch amber in terf ace assem b ly

• Filte r holde r

• Sa m p le flow control

• Extraction interface flo w control

• Dilution flow control

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 18 of 20R egul at or
Pr e s s u r e Gauge 2- w a y Va l v e R egul at or F ilt e r H o l der

D- M F M Po r t A dapt or C o r r os i v e T r ap De ss i c a n t D r ye r

P l enum

Co m p r e s s e d Ai r Su p p l y Pu m p T o E x haus t S t il lin g C ham ber

D e ssi c a n t Dr ye r D i l u t i on F l ow I n t egr at or E x tr a c ti o n A sse m b l y To t a l Fl o w I n t egr at or

To E x haus t E duc t o r T- MFM

Qui c k D i s c onnec t o r

N eedl e Va lv e N eedl e Va lv e 2- w a y Va l v e Co m p r e s s e d Ai r Su p p l y T her m o c oupl e

Figure 6: S c hematic flow diagram of the sampling train used in Phase I and II XFM validation t e sts. A photograph of the assembled extraction-interfa ce and filter holder is shown in Figure 7. The port adapter is on the left side in the photograph and consists of PTFE-coated 2-inch diam eter stainless steel (SS) t ubing with a san ita ry f l ange f o r

atta ching th e assem b ly to the stilling chamber. In the case of norm a l stack sampling, this interfa ce would be attached directly to a large d i am eter shielded probe type of sam p le extraction system . This port adapte r is f o llowed by a n extra c tion assem b ly thatdraws stack gas at the rate of about 20 to 30 lpm into it using an eductor and flow control module. A representative sub-sam p le of this stack gas is blended with dry d ilu tio n gas in th is assem b ly pr ior to being drawn through the SS sa m p le filter holder assem b ly shown on the ri ght side of the photograph. The sample and dilution flow rates are on the order of one to two lpm and controlled by the sam p le and dilution flow control components. All tem p er atures and flows are controlled, m onitored and recorded during sam p ling.

Figure 7: P h otograph of the assembled port adaptor, extraction assembly and filter holder. An exploded schem a tic view of the XFM f ilter h o lder with f ilte r cass e tte is illus t ra ted in Figure 8. T h e f ilte r cass e tte shown in the m i ddl e contain s an of f

- the-shelf upstream PTFE f ilter, Tef l o TM by Pall I n c. 23 which traps PM and a downstrea m reactiv e f ilte r tha t is u s ed to

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 19 of 20trap vapo r p h ase m e tals. The f ilter s are lo aded into the f i lter cassette in the labor ator y and transpo r ted to and from the field in p l astic Pe tri dishes. The field engineer sim p ly removes the f ilter ca s s ette f r om its Petri d i sh and place s it in the SS f i lter ho lder. W h en sam p ling is f i nished, the f ilter casse tte is rem oved f r om the f ilter holde r an d return ed to its Petri d i s h. In this pro cess, the f ilters a r e nottouched by the field engineer, wh ich reduces the possibility of contam inating and/or di sturbing the deposits. The analyte m a ss on each XFM filter deposit is d e term ined by EPA Compendium Method IO-3.3 14

. This m e thod is the sam e as one used to m easure 48 am bient m e tals for thousands of f ilter s collec ted by EPA’s PM 2. 5 Speciation Program 15

. The aeroso l concentratio n of each me tal is calcu l ated us ing Equation 3.

XFM d XFM t REO i PTFE i XFM e i V V M M C

− +
= −

− 7 Equation 3

Where:

= Concentration of the i e-XFM i C th analyte in th e em issions m easured by the XFM

= XRF-determined m a ss of the i PTFE i M th analy t e on the PT FE f ilter.

= XRF-determined m a ss of the i 7

− REO i M th analy t e on the reactive filter (REO-7 23 )

= Total volum e (em i ssion plus dilution) sam p led by the XFM XFM t V

= Volum e of dilution air dr awn throughfilters of the XFM

XFM d V
Mass and vo lum e m easurem ent uncertainties ar e typically on the orde r of one to three percent of the value near th e em ission lim it concentrations . T h is suggests XFM aerosol concentratio n uncertainties on the or der of three to five percent.

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 20 of 20Figure 8: E x ploded schematic view of XFM filter holder with filter cas s ette. 3.3 Xact Instrumental Analyzer Procedure The Xact ins t rum e ntal an alyzer procedure (Xac t-I A P) has the ability to provide stack gas m e tals analy s is re sults f o r up to 20 metals ev ery 15 m i nutes. This capability could greatly f acilitate tr ia l burn tests, engineering/design studies as well as com p liance testing by providing near real tim e result s necessary for rapid evaluation of engineering and/or burn conditions, or com p liance success or failure. Th is candidate conditiona l reference procedure is based on sam p ling of PM and vapor phase m e tals using a reactive filter tape (PRO-11 24 ) f o llowed by XRF determination of metal m a ss in the resu lting deposits wh ile the next s a m p le is being collected on a f r e sh section of f

ilter tap e
. The Xact instrum e ntal analyzer draws a con tinuous representative sam p le of 25-100 lpm of stack gas through a stilling cham ber. A s m all is okinetic sub-sam p le (~1 lpm ) is extracted from the stilling cham ber and blended with a bout 0.2 lpm of dilution gas. The cooled and diluted stack gas is drawn through the reactive f ilter tape where the m e tals are quantitatively trapped. Following collection, th e tape is advanced to an XRF analyzer for m e tal m a ss determ inatio n while another sam p le is collecte d. The Xact ta kes the XRF-dete rm ined m a ss in μ g/sam p le divides this m a ss by the stack gas vol um e for the run, and reports concentrations

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 21 of 23for up to 20 analyte m e tals in μ g/dscm. Response tim e depends upon the end-user’s required detection lim its, but is typically 10 to 30 m i nutes. Figure 9 shows key Xact com ponents. The Xact ha s a two-foot by three-fo ot footprint and is four-feet tall. Concentrations are d e term ined by the Xact c ontroller, and autom a tic flow, upscale, and blank check s are av ailab l e to en sure that c a lib ra tion is m a intained. All da ta is stored in a personal computer and can be easily imported into a spreadsheet or data acquisition system . XRF calibration is stable over extended periods. Its calibration is checked daily, but rarely needs recalibration m o r e frequently than once or twice a year. The Xact co nsists of the followi ng five subsystem s (Figure 9):

• Sample inte rface : The s a m p le interface withd r aws a repres entative sam p le of effluent from the source and delivers it to the sampling m o dule. The Xact sam p ling probe utilizes a shrouded probe type design to draw a representative sam p le of effluent from the source. The effluent is then transported from the probe through a heated transport line to the sam p ling module.

• Sampling module: Th e sam p ling module consists of all th e equipm ent necessary for extra c ting all elem ents o f interes t f r o m the flue gas. The Xact draws a flow of between 25 and 100 lpm through a stilling cham be r where the flow is slowed prior to withdrawing a sub-sam p le of about 0.50 to 1.0 lpm for analysis. About 0.20 lpm of dilution air is added and drawn throu gh chem ically rea c tiv e f ilte r tape. Th e m e tal analytes of interest are captured qu a n titativ ely o n this f i lter tape.

• Volume me asurement module: After being d r awn through the filter tape the flue gas is dried and the total gas flow rate is m easured. The sam p le f l ow rate is calcu lated b y subtracting the dilution flow from total flow . The flow is totalized over the sam p ling period to obtain a volum e m easurement. Because the flue gas has been dried prior to m easure m ent, the volume and reported aeros ol concentration are reported in units of dry standard cubic m e ters (dscm )

.

• X-Ray analysis module: The Xact m easures the m a ss for each m e tal using XRF analysis in accordance with the procedures listed in EPA’s CompendiumMethod IO3.3 14

.

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 22 of 23Figure 9: Overview of Xact-IAP components and flow sc hematic.

• Data recorder: The m a ss as determined by XRF is divided by the sam p le flow rate using Equation 4 and recorded by the Xact c ontroller. The data can then easily be im ported into a data acquisition system or can be stored on a personal computer as a text file.

) V V ( M C XACT d XACT t XACT e i e i

−

= − Equation 4

Where:

e i C = Concentration of the i th m e tal in the em issions measured by the Xact

XACT e i M − = Mass of the i th m e tal in the sam p le as m easured b y XRF.

XACT t V = Total volum e as m easured by the Xact

XACT d V = Dilution volum e as m eas ured by the Xact

M e thod 301 E v al. : V1. 0 Section 3.0 Methods Page 23 of 23The Xact als o incorporates a num ber of procedur es to ensure the accuracy and reliability of its data. At leas t once each day the X act perform s upscale and zero checks. The values reported each day are co mpared withthe origin al calib ration to ensure th e accuracy an d stability of the XRF analyzer. The X act also has a palladium rod perm anently m ounted into the XRF analysis area. T h e reported concentrat ion of this rod is a known and checked with every sam p le analyzed o n the Xact. The volum e m easurem ent is com p ared at le ast on ce a day against another m a ss flow m e ter. In addi tion the calibration of the XRF analysis can be checked for all elem ents using NIST traceable thin film standards and th e accura cy of the flow m e ters can be verified by checking them with a NIST traceable flow m e asurem ent device su ch as a DryCal ® me t e r 25

.



### 4.0 Calculati o ns 4.1 Overview This section summarizes key calculations for Ph ase I and II testing with a more detailed discussion presented in Appendix K. Calc ulations for the QAG, XFM and Xact-IAP are shown in the next three subsections while Subsection 4.6 presents the calculations of com p arison param e ters such as bias and precisi on. The Phase I and II test results show that background concentrations of the five MACT m e tals in the stack gas and laboratory air were essentially equal to zero, and that the concen tration of the spiked reference aerosol was constant to within a few percent. This lo w background and constant concentration allowed for the determ ination of bias and precision us ing replicate seq u ential m easurem ents ins t ead of paired m e asurem ents. This in turn allowe d for sim p ler calculations of validation m e trics as discussed in Subsections 4.6 and 4.7.
4.2 List of Symbols and Terms

0 b = y intercept

1 

### b = slope B = bias 

### B = absolu te v a lue of the b i as

D 

### C = m i ni m u m detection lim it

i C = concentration of the i th elem ent

a i C = concentration of the i th elem ent in the aeroso l

i 

### C = m ean concentration of the i th elem ent

a Pb C = concentration of lead in the aerosol

s i C = concentration of the i th elem ent in the solution

s Pb C = concentration of lead in the solution

u j i 

### C

, = concentration of the i th upscale m e tal repo rted f o r the j th inte rval

u c i 

### C

, = concentration of the i th upscale m e tal repo rted at calibration

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 24 of 75L i C = Em ission lim it of the i th m e tal

z j i 

### C

, = Blank concentration of the i th m e tal reported for the j th interv al

z c i 

### C

, = Reference value of the low le vel ca libr a tion sta ndard for the i th m e tal

M i C = m ean m e t a l concen tration

M a i C − = concentration of the i th elem ent in the aeroso l as m easured by the cand i date
m e thod M a i C − = m ean concentration of the i th elem ent in th e aerosol as m easured by can didate
m e thod QAG a i C − = concentration of the i th elem ent in the reference aerosol generated by the QAG
XACT a i C − = concentration of the i th elem ent in the aerosol reported by the Xact

XFM a i C − = concentration of the i th elem ent in the aeroso l measured by the XFM QAG s i C − = concentration of the i th elem ent in the standard solution used for the QAG
7

− REO i C = concentration of the i th analyte on the XFM reactive filter 23

PTFE i C = concentration of the i th analyte on the PTFE f ilter
11

− PRO i C = concentration of the i th analyte on the Xact reactive filter CD i = i th elem ent calib ration drif t CF i = correction factor for th e i th elem ent 

### d = averag e of differences E i = efficiencyof the i th elem ent

e F = flow of ex panded nebulizer air in the QAG

t F = tota l spik e d f

l ow

v M = m a ss of water vapor in a liter of saturated air

PTFE i M = XRF-deter m ined m a ss of the i th analyte on the P T FE f ilter
11

− PRO i M = XRF-deter m ined m a ss of the i th analyte on the Xact rea c tiv e f ilte r 23

7

− REO i M = XRF-deter m ined m a ss of the i th analyte on the XFM reactive filte r XACT e i M − = XRF reported m e tal mass on the f ilter (μg / f ilter )
n = num ber of m easurem e n ts i 

### p = precision f o r the i th elem ent

c P = absolu te p r essur e of the com p ressed nebuliz er air in the Q AG

e = pressure of the expanded nebulizer air in the Q AG P PRB i = percen t relative b i as fo r the i th element PRSD = percen t re lativ e standard deviation
r = correlatio n coefficient

2 r = Square of the correlation coefficient

f R = f ilte r ra tio to conf irm total m e tal tr apping ef f i ciency with th e XFM f ilter s
Pb i R = relativ e ra tio f o r the f o r

the i th elem ent divided by the concentration of lead

m R = total rate of solution mass loss for the QAG

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 25 of 75RM R = averag e of the RM data set

v R = rate of vapor loss of the QAG standard solution RA = relativ e accuracy RSD = relative standard deviation 

### SD = standard deviation SDM = standard deviation of the m eans M i SDM = standard deviation of the m ean of a se ries of concentration m easurem ents of the i th elem ent t = t-s t atistic

t V = tota l volu m e sam p led

d V = volum e of dilution air drawn through the XFM

XFM t V = total volu m e sa m p led through th e XFM filters

XFM d V = volum e of dilution air drawn throu gh the XFM f ilter s XACT t V = total volum e sa m p led during Xact run (dscm )
XACT d V = volum e of dilution air during Xact run (dscm )

B i U = Uncerta inty in the i th elem ent bias QAG a i U − = Uncerta inty in the i th elem ent reference aero s ol concentratio n

i x = value of the i th data point for data set 

### x
x = averag e of the valu es in data set 

### x

i y = value of the i th data point for set of data y y = averag e of the valu es in data set y ZD i = i th elem ent zero drift

4.3 QAG Reference Aerosol Concentration Calculation of the QAG generated referen ce aerosol concentra tion was based on a m easure m ent of the nebulizati on rate of analyte-containing solution and a m easure m ent of the rate of flow of gas into which the nebu liz ed s o lution d r op lets wer e in jected. The concentration of this refe rence aeroso l was calculated using the following equation: 

### ) R (R F C C v m t QAG s i QAG a i 

### − = −

− Equation 1 (see Section 3.1)

Where:
a-QAG i C = QAG reference aerosol concentration of the i th elem ent (μg/dscm )

s-QAG i C = Concentration of the i th elem ent in the solution (μg/g) F

t = Total sp iked ref e rence ae rosol gas f l o w rate (ds c m / m i n) R m = Measured rate of solution m a ss loss from a reservoir (g /m in)

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 26 of 75R v = Reservoir m a ss loss rate due to wate r vapor loss ( g /m in) The tota l solution use rate ( R m ) was d e term ined by m easuring the m a ss of the solu tion reservoir every 15 seconds and determ ining the sl ope of a scatter plot of this m easured m a ss versus tim e . The rate of water vapor loss wa s calculated using to the following equation: 

### ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

− =

c e v e v 

### P P 1 M F R Equation 2 (see Section 3.1)

Where: F

e = Expanded nebulization air flow ra te as m easured by the flow m e ter on the nebuliz ing air line. M v = Mass of water vapor containe d in a liter of water vapor saturated air at 32 °F. This value has been well defined and is listed as 4.84 m g /liter 26 P e = Pressure of the expanded ga s outside the nebulizer nozzle. Since the d r oplet gen e rating cham ber and the d r o p let s i ze selector are open to the atm o sphere, P e is the atmospheric pressure recorded from a field barom e ter during Phase II testing and was assum e d to be 14.7 psi for Phase I testing that was conducted at near sea level. P c = The absolute pressu re of the com p ressed air up stream of the nebulizer aspiration nozzle, recorded from the precision pressure gauge located on the nebulizer air line (psi).
4.4 XFM Measured Aerosol Concentration The XFM determ ined concentration of the five MACT m e tals in the QAG-generated ref e rence ae rosol is base d on a m easurem ent of the m e tal m a ss deposited on the XFM f ilter s and the sam p le volum e that passed through the f ilters. The total volu m e that passed through the XFM filter cass e tte and the volu m e of diluti on air were recorded with flow integrators and an operator during each XFM run. Sa m p le volum e was calculate d by subtracting the dilution volum e f r om the tota l volu m e. Metal mass concentrations in m i crogram s per spot were determined using a CES XRF a n alyzer and procedures define d in E P A’s Inorganic Compendium Method 3.3 “Determi nation of Metals in Ambient Particulate Matter Using XRay Fluores cence Spectr o scopy” 14 The XFM determ ined concen tr ation s were calcula ted using the following equation:

XFM d XFM t REO i PTFE i XFM a i V V M M C

− +
= −

− 7 Equation 3 (see section 3.2)

Where:

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 27 of 75= XFM m easured concen tration of the i a-XFM i C th elem ent in the ae rosol (μg/dscm )

= XRF-determined m a ss of the i PTFE i M th analy t e on the PT FE f ilter

7

− REO i M = XRF-determined m a ss of the i th analy t e on the reactive filter (REO-7) 23

= Total volum e sam p led during XFM run (dscm ) XFM t V

= Volum e of dilution air drawn throughfilters XFM run (dscm )

XFM d V
4.5 Xact-IAP Measured Aerosol Concentration During a sample run, the Xact recorded the to tal dry volum e of gas that passed through the filter tape. F o llowing th e sam p ling period, th e tap e was advan ced to th e XRF analysis region where each m e tal’s m a ss was determ ined in m i crogram s per spot. The m a ss was then divided by the total dry volum e for a given sam p le run to produce concentrations in μ g/dscm . Xact concentratio ns for these tests were ca lculated using the following equation:
) ( XACT d XACT t XACT i Xact a i V V M C

− = − Equation 4 (see Section 3.3)

Where:

Xact a i C − = Xact reported concentration of i th elem ent in the aerosol (μg/dscm )

XACT i M = XRF reported m e tal m a ss on the filter (μg/filter)

XACT t V = Total volum e sam p led during Xact run (dscm )

XACT d V = Volum e of dilution ai r during Xact run (dscm )
4.6 Validation Comparison Parameters
4.6.1 Bias The proposed candidate conditiona l m e thod bias was determ ined by comparing the candidate

m e thod’s mean m easured concentration ( M a
i C − ) to the calcu lated reference aero sol analyte concentratio n ( ). The bias ( B ) of the proposed candidate con d ition a l m e thod is defined as the difference between the m ean candidate m e thod m easured aerosol concentratio n and the calculated refere nce aerosol concentration over a co mmon m easurem ent interva l; i. e
. , QAG a i C −

Equation 5 QAG a i M a i i 

### C C B − −



### − =

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 28 of 754.6.2 Bias Significance Test The test for significance of bias us ed in this report is different from that used in Method 301 prim arily because sequ ential m easurem ents were used in these tests instead of paired m easurem ents, but also b ecause the u n certainty in the reference aeroso l co ncentration was significant relative to the standa rd deviation of the m ean of t h e m easurem ents. In this case, the criteria f o r bias s i gnificance is w h ether o r not the bias is greater than two tim es (95% confidence level) the un certainty in the bi as. The uncertainty in the bias for the i th element ( ) is given by the following equation when a reference aerosol spike is used: B i U 

# ( ) ( ) 2 2 M i QAG a i B i SDM U U + = − Equation 6

Where:

B i U = Uncerta inty in the i th el ement bi as
QAG a i U − = Uncerta inty in the i th elem ent reference aero s ol concentration

M i SDM = Standard deviation of the m ean of a series of concentration
m easurem ents of the i th elem ent Thus, the bias is significant at the 95 % conf idenc e leve l if

. B i i U B 2 >
4.6.3 Correction Factor The correction factor is a factor used to correct f o r significan t differences between m e asured and reference concentration; i.e., efficiency di fference in the case of the QAG or bias in the case of the XFM and Xact. If the efficiency or bias is determined to be significant, a correction factor for th e i th elem ent ( CF i ) can be calculated using the following equation and applied to future m easurem ents to compensa te for the m e thod’s bias or inefficiencies.

M a i QAG a i i C C CF

− −

= Equation 7

4.6.4 Drift Drift is generally defined as a percent change in a m ean value m easured over an ex tend ed period of tim e . It is prim arily applicable to the Xact CEMS and Xact-IAP and based on a com p arison of zero and upscale m easurem ents with those m a de when the instrum e nt was last calib rated. These m easurem ents are indica tor s of instrum e nt calibra tion drif t ( CD i ) and zero drif t ( ZD i ). These drift v a lues are calculated using the following two equations, which are based on equations used in proposed perform a nc e specifica tion 10 for multi-m etal CEMS.

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 29 of 75

# ( ) % 100 C C C CD u c , i u c , i u j , i i −

= Equation 8

Where: CD i = i th elem ent calib ration dr if t

u j i 

### C

, = Concentration of the i th upscale m e tal repo rted f o r the j th inte rval

u c i 

### C

, = Concentration of the i th upscale m e tal repo rted a tcalibra tion 

# ( ) % 100 , , L i z c i z j i i C C C ZD − = Equation 9

Where: ZD i = i th elem ent zero drift

z j i 

### C

, = Blank concentration of the i th m e tal r e ported f o r the jth inte rv al

z c i 

### C

, = Reference v a lue of the low leve l calibration stan dard for the i th

m e tal

L i C = Em ission lim it of the i th m e tal 4.6.5 Efficiency Efficiency as used in this docum ent is defined as the ratio of a m easur ed concentration to a reference concentration expressed as a percent. In the case of the QAG, for exam ple, it is the ratio of the aerosol concentration m easured in the Xact stilling cham ber to the ca lcula t e d reference aerosol concen tration. Efficiencies other than 100% are due to generation and transpo r t inefficiencies and/or errors associat ed w ith the generation and m e asurem ent of the aerosol concentration. T h e efficiency ( E i ) of the i th elem ent is calculated using the following equation:

% 100 QAG a i M

a i i C C E

− −

= Equation 10

4.6.6 Efficiency Significance T e st The criteria for efficiency significan ce is wheth e r or not the difference b e tween the m easured efficiency and 100% is greater th an two tim es (95% confidence le vel) the uncertainty in this

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 30 of 75difference. The uncertainty in th e efficiency for the i th elem ent ( ) is given by the following equation when a refere nce aerosol spike is used: E i U

2

M a i M

a i 2
QAG a i QAG a i i E i 

### C SDM C U E U ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

=

− −

− − Equation 11 (See Section 4.6.2)

Thus, the efficien cy is s i gnificant at the 95% confidence level if

E i i U E 2 100 >

− Equation 12

4.6.7 Filter Ratio A validation param e ter c a lled f i lte r r a tio ( R

f ) was used as an indicato r to c onf irm total m e tal trapp i ng efficiency with the XFM filters. The m a ss of the low volatility metals Pb and Cr as
m easured on the XFM PTFE f ilter ( ) and the f o llowing reac tive f ilte r ( ) were used in th is calcu lation. Th e filter ratio is cal culated using the following equation : PTFE i M 7

− REO i M

% 100 7

− + = REO i PTFE i PTFE i f M M M R Equation 13

4.6.8 Linearity Evaluation of linearity of the QAG and the candi date conditional m e thods was based on four param e ters derived from a linear least square s fit of the m easured concentration plotted agains t the reference con centration ; i. e., slope, in tercep t, correlation coe fficient and variance. Given a general set of data with n data points, the slope ( b ) , ( i i y x 1 ), y-intercep t ( b 0 ), correlation coefficient ( r ), and the variance ( r 2 ) are defined by the following equations: 

## ( ) ( ) ( ) 

## ∑ ∑

− − − = 2 1 x x y y x x b

i i i Equation 14

x b y b 1

0 −

= Equation 15

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 31 of 75

## ( ) ( ) ( ) ( ) 

## ∑ ∑ ∑

− − − − = y y x x y y x x r i i i i 2 2 Equation 16

4.6.9 Mean Concentration
The m ean metal concentration ( M i C ) m e asured by a candidate co ndition a l m e thod is equ a l to the sum of t h e individual m easured concentrations ( C i ) divided by the number of m e a s ured concentratio ns ( n ).

n C C i

M i 

## ∑

= Equation 17

4.6.10 Metal Ratio As used in this report, the m e tal ratio ( ) is the r a tio of the i th m e tal aerosol concentration
norm a lized to the Pb aerosol concentration divided by the i th m e tal solution concentr ation norm a lized to the Pb solution concentration; i.e., Pb i R

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

=

s Pb s i a Pb a i
Pb i C C C C
R Equation 18

4.6.11 Percent Relative B i as The percen t relative b i as for the i th el ement ( P RB i ) is the i th el ement bi as ( B i ) divided by the reference aerosol concen tration for th e i th elem ent ( ) tim e 100%, i.e., QAG a i C −

% 100 QAG a i i i C B PRB

− = Equation 19

4.6.12 Precision Precision is an indicator of th e degree of m u tual agreem ent between ind i vidual m easurem ents of a param e ter having the sam e va lue. In th is re port it is d e f i ned as the p e rcen t re lative standard deviation (PRSD) of a series of m easurem ents of the sam e aerosol concentration held constant over a relative shor t test period in contrast to st ability, which is the PRSD of a series of m easurem ents determ ined over an ex tended period of tim e. The precision f o r the i th elem ent ( P i ) is given by the following equation:

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 32 of 75% 100
i i C SD PRSD P = = Equation 20

Because there is random variab ility associated with both th e reference aerosol concen tration as well as the m easured aerosol concentration, the m easured pr ecision is an indicator of the variability introduced by all com ponents of the generation-m easure m en t system ; i.e., QAG and candidate conditional m e thod. For this se ries of tests, the m a gnitude of the QAG precision is considered to be sim ilar to th e candidate conditional m e thod. As such, the precision of the QAG or candidate conditional m e thod is defined as the m easured precision divided by the square root of 2. 4.6.13 Standard Deviation The standard deviation ( SD ) in the c oncentr ation is equa l to the square root of the sum of the differences between the m ean concentration and individual concentration m e asurem e n ts squared, divided by the num b er of m easure m ents less one. 

# ( )
1 2

− − = 

# ∑

n C C SD i i i Equation 21

4.6.14 Standard Deviation of the Mean The standard deviation of the m ean ( SDM ) is eq ual to the SD divided by the square root of the num ber of m easurem ents ( n ).

n SD SDM i i = Equation 22

4.6.15 t-statistic

Equation 23 

### SDM

B t =

4.7 Other Comparison Parameters
4.7.1 Detection Limits The m i nim u m detection lim it, C D , is defined as the sm allest c oncentration that a p a rticular m easurem ent can detect. Using the definition developed by C u rrie 27 detection m a y be

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 33 of 75considered reliab l e when the probab i l ity of detecting a concentration C D is sufficiently large (95%), while the probability of incorrectly de tecting a blank is sufficiently sm all (5%). Using this definition of detec tion and the selected probabilitie s (95% and 5%), it can be shown that:


### SD C D 

### 29

. 3 = Equation 24
where SD is the standard deviation of observed results when the true concentration is zero; i.e., standard deviation of a se ries of blank m easurem ents. The m i ni m u m detection lim it of a candidate co ndition a l m e thod will b e the analytic al detection lim it as defined above using a blank filter, divided by the typi cal volum e of sta c k gas sam p led; i.e., about 0.012 dscm for the Xact-IA P and 0.03 dscm for the XFM. 4.7.2 EPA Relative Accuracy The EPA ha s defined a figure-of-m erit to evalua te candidate m easure m ent m e thods relative to current reference m e thods or standards. This figure-of -m e r it, called relative accuracy, includes both a com pone nt for bias and a com p onent for precision, which is designed to exclude im precise m e thods with low bias as well as precise m e thods with high bias. However, it does not take into consideration unc ertainties in reference m e thod m easurem ents nor can it be related to a stat istically defined level of confid ence. Although this EPA-defined relative accu racy term has proved useful in so m e cases, it is n e ither requ ired nor is it considered appropriate f o r this evalu a tion. It is d e fined here because it is discussed in this report.

RM i R SD n t d RA 975

. 0 +

= Equation 25

Where: RA i = Relativ e accuracy for the i th elem ent 

### d = Arithm e tic m ean of the dif f e rence, d , of paired CEMS and reference m e thod (RM) data set SD = Standard deviation

RM R = Average of the RM data set

M e thod 301 E v al. : V1. 0 Section 4.0 Calculations Page 34 of 75

### 5.0 Quality Control and Assurance
5.1 Overview The overall objectives o f Quality Control (QC) and Assuranc e (QA) f o r these tes t s w e re to assure and d o cum e nt that the accuracy of the m e a s urem ents were 1) NIST traceable and 2) supportive of the m e thod validation goals stated in the test plan (Appendix A). It is clear that these goals were m e t as evidenced by th e high level of agreem ent between the QAG genera ted re ference ae ro sol c oncentration and the independently m easured XFM and XactIAP aerosol concentrations (±5% ) as discussed in the following section. Overall, the Q AG and candidate m e thods showed good QA/QC and all 240 Xact-IAP and 50 XFM runs taken during QAG operations were cons idered to be valid. Mass, tem p erature, pressure, XRF standards check, Xact-IAP upscal e, Xact-IAP blank, and Xact-IA P thin film m e asurem ents, etc. m e t the test p l an objectiv es. The com p lete QA/QC database and calculations are presented in Appendices G and H, and the or iginal QA/QC data sheets are provided in Appendices I and J. This section provides a sum m a ry of key QA/QC results and issues for the QAG, XFM, and Xact-IAP Phase I and II tests. 5.2 QAG Generating an aerosol with an accurate NIST -traceable concentration with the QAG required control of such param e ters as m a ss, flow , tem p erature, and pressure. The prim ary m easurem ents f o r these param e ters a ll m e t the te st plan ob jec tives. One k e y param e ter, standard solution use rate (R m , Equation 5), was a calculated pa ram e ter based on the slope of a plot of reservoir m a ss versus tim e . A lthough the balance used for the reservoir m a ss m easurem ent was NIST traceab le to b e tter than 1 % , the uncertain ty in th e slope (us e rate, g/m i n.) for any particular period was on the or der of a few per cent. The Q AG solution use rates during Phase I and II test pe riods are listed in Table 6. The plots from which these rates were determined are shown in Figure 10 and Figure 11. For both phases, the total m a ss consum ption was reaso n ably stable with an average correlation ( r ) of better than 0.99 and an average standard solu tion consum ption rate of 0.112 ± 0.009 g/m i n. The total consum ption rate depends upon the rate of solu tion droplet generation and evaporation. Since the nebulizer em its at a c onstant rate as soon as it begins operation, the QAG metal em ission rate is stable after only a few m i nutes. The evaporation rate; however, is dependent upon the temperature of soluti on reaching a steady state, which typically requires several hours of operation if the solution has not been pre-cooled. QAG evaporation rates are typ i cally 20-30% of the total solution consum ption rate. For both phases, the tem p erature of the flow was cont rolled to 32oF using an ice water bath and bubbler, pressure was maintained between 17 an d 19 PSI, and flow was kept constant at 10.1 slpm . The a m bient pressure is also used to de term ine evaporation rate and was assumed to be 14.7 PSI for Portland, O R and 14.3 PSI for Lafa yette, IN 28 . Uncerta inty in the ev apo r ation rate is on th e order of 1 0 % resu lting in a 2-3% u n certainty in the to tal so lution consu mption rate.

M e thod 301 E v al. : V1. 0 Section 5.0 Quality Con t rol and Assurance Page 35 of 75Table 6: QAG Emissio n Rates for Phase I and II. Test Ph a s e Dat e Ru n Co rr C o e ff. QA G Ra te I 1 5-Dec

- 04 1

- 1 2 0.99 9 0 .1 05 I 1 6-Dec

- 04 13-16 0.99 2 0 .1 21 I 1 6-Dec

- 04 17-20 0.98 9 0 .1 05 I 1 6-Dec

- 04 21-24 0.97 3 0 .1 05 I 1 7-Dec

- 04 25-26 0.92 6 0 .1 10 I I 4-Mar-05 1

- 1 2 0.99 7 0 .1 30 I I 6-Mar-05 15-18 0.97 6 0 .1 08 I I 7-Mar-05 19-22 0.99 5 0 .1 14 I I 8-Mar-05 23-26 0.99 7 0 .1 10 0.98 3 0 .1 12 0.02 3 0 .0 09

2. 4 7 .6 Avg. SD PRS D
On March 5 th , the QAG experienced problem s with fr eezing in the nebulization chamber. Although the cham ber and the tubing leading to it we re m a intained at 32oF , it is believed that the expanding gas and solution ev ap oration in th e cham ber lowered the s o lution to be low its freezing point. The stain l ess steel tub i ng lead ing to the nebulizer was rep l aced with T ygonTM tubing which helped m a intain the temperat ure above freezin g. Two XFM runs, 13 and 14, were taken during this tim e and were in good agreem ent with the X act-IA P (less than 10% difference). These two XFM runs, however, we re disregarded since they could not be com p ared to the predicted QAG conc entrati on because of the above noted QAG freezing problem

.
X F M R un 1- 12

y = - 0

. 1 05 4x + 8 8 1

. 0 2 R 2 = 0. 99 88
700 730 760 790 820 850 880 910

0 2 50 50 0 7 5 0 1, 00 0 1 , 2 5 0 1 , 500 E l a p s e d T i m e ( m in)Mass (g)

X F M R un 1 3 - 1 6

y = -0. 121 x + 108 0. 3 R 2 = 0. 99 18 1 , 055 1 , 060 1 , 065 1 , 070 1 , 075 1 , 080 1 , 085

0 2 5 5 0 7 5 100 125 15 0 1 75 2 0 0 El a p s e d T i m e ( m i n )Mass (g) X F M R u n 21- 24

y = - 0

. 1 05 1x + 8 0 8

. 9 R 2 = 0. 9 731

800 801 803 804 806 807 809 810

0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 E l a p s e d T i m e ( m in)Mass(g)

X F M R un 1 7 - 2 0

y = -0. 105 x + 107 1. 1 R 2 = 0. 98 94 1, 0 4 5 1, 0 5 0 1, 0 5 5 1, 0 6 0 1, 0 6 5 1, 0 7 0 1, 0 7 5

0 2 5 5 0 7 5 1 0 0 12 5 1 50 175 200 E l ap s e d T i m e ( m in )Mass(g) X F M R u n 25- 26

y = -0. 109 9x + 19 23. 5 R 2 = 0. 9 261 1 , 916 1 , 917 1 , 919 1 , 920 1 , 922 1 , 923 1 , 925

0 5 1 0 15 20 25 30 3 5 40 4 5 50 E l ap s e d T i m e ( m in )Mass (g)

Figure 10: QAG solution mass loss rate durin g Phase I testing.

M e thod 301 E v al. : V1. 0 Section 5.0 Quality Con t rol and Assurance Page 36 of 75M a r c h 6, 20 05 R uns 15 - 1 8

y = - 0

. 1 0 8 x + 1 7 7 5 R 2 = 0. 9 7 59
1745 1750 1755 1760 1765 1770 1775 1780

0 4 0 8 0 1 20 160 200 240 E l apse d T i m e (m i n )mass(g)

M a r c h 7, 20 05 R u n s 1 9 - 2 2

y = - 0 .11 44x + 176 5.4 R 2 = 0.99 49 1710 1720 1730 1740 1750 1760 1770

0 4 0 8 0 120 160 200 240 280 320 360 E l ap se d T i m e ( m i n )mass(g) M a r c h 8 , 2 005 R uns 23- 26

y = -0. 1 0 9 8 x + 15 33

. 7 R 2 = 0

. 9 9 7
142 0 144 0 146 0 148 0 150 0 152 0 154 0

0 100 200 3 0 0 400 5 0 0 600 700 800 900 E l ap se d T i m e ( m in )mass(g) M a r c h 5, 2 005 R uns 1 - 1 2

y = - 0 .13 04x + 176 7.7 R 2 = 0.9 969 1700 1710 1720 1730 1740 1750 1760 1770 1780

0 5 0 100 150 200 250 300 350 400 450 E l ap se d T i m e ( m in )mass(g)

Figure 11: QAG solution mass loss rate durin g Phase II.

5.3 XFM The XFM was operated for 26 runs during each test phase. O t her than the two runs that could not be com p ared to the QAG becau se of solu tion freezing, all XFM runs were considered valid and were used in calculating Q AG effi ciency and XFM bias and precision. The XFM reports concentrations in m a ss pe r volum e . As pa rt of the QA pr ocedures for these tes t s, the XFM m a ss and volum e m easure m ents were eval uated for accuracy using NIST-traceable standard s. For these tests, th e XRF reported con centr ation s within 5% o f the NIST standards (SRM 1832 and 1833) for all elem ents m easured during calibration, and a ll of the daily XRF QA m easurem ents were within 5% of the valu es obtained imm e diately after c a lib ratio n. For this reason, no changes were m a de to any of the reported XRF m e tal m a s s concentrations.
The XFM dilution and to tal f l ow m e ters were found to be biased during Phase I tests by about 5% as indicated below in Table 7. In addition, the XFM dilution flow m e ter was found to be biased by about 6% during Phase II te sts (Table 8). These flow m e ter bias determ inatio ns were m a de using a NIST traceab le DryCalTM prim ary flow sensor. Following Phase II, the DryCalTM was reevaluated by the m a nufacturer and was found to be within 0.1% of the NIST standard. If a m e ter exhi bited an average bias of m o re than 5%, a correction factor was applied to the recorded flows and subs equent calculations. Thus, correction factors of 5 to 7 % we re applied only to the biased XFM flows as noted above.

M e thod 301 E v al. : V1. 0 Section 5.0 Quality Con t rol and Assurance Page 37 of 75Table 7: Flow meter evaluation during Phase I.

MF M D r y C a l
s l pm s l pm A QAG Neb Air 1 01/03/ 05 10.7 1 0.8

- 0.8 N o - - B X F M T o tal 10/20/ 04 1.32 1.25 5.6 Y es 0.95 C X F M Dilution 10/20/ 04 0.75 0.71 5.0 Y es 0.95 D X F M Ex tr ac t 12/16/ 04 18.8 1 8.5 1 .1 No

- - E O ver a ll F l ow 12/16/ 04 110.4 1 13.3

- 2 .6 No

- - F X ac t ( S am p, Dop) 03/03/ 05 0.71 0.70 0.8 N o - - G X ac t Dopant 03/03/ 05 0.20 0.20

- 0 .4 No

- - Flow Co rr. f o r

M 301 Flow s Co rr. Fa c t or Date % Di ff. Me t e r Flow Che c k

Table 8: Flow meter evaluation during Phase II.

MF M D r y C a l MF M D r y C a l slp m slpm slp m slp m A Q A G Neb Ai r 1 01/03/05 10.7 10. 8

- 0.8 3 /9/2005 10.7 10.4 2 .7 0.9 N o - - B X F M T o tal 10/20/04 1.32 1.2 5 5.6 3 /8/2005 1.60 1.57 1.9 3 .8 N o - - C X F M Dil u ti on 10/20/04 0.75 0.7 1 5.0 3 /8/2005 0.75 0.70 7.9 6 .5 Y e s 0 .94 D X F M Ex tr ac t 12/16/04 18.8 18. 5 1 .1 3 / 8/2005 16.8 16.2 3 .2 2.2 N o - - E O v e r a l l Flow 12/16/04 110.4 113.3

- 2.6 3 /25/2005 104.2 103.6 0 .6

- 1 .0 N o - - F X ac t ( Sam p, D op) 03/03/05 0.71 0.7 0 0.8 3 /8/2005 0.71 0.70 1.1 0 .9 N o - - G X ac t D opant 03/03/05 0.20 0.2 0

- 0 .4 3 / 8/2005 0.20 0.21 -5.8

- 3 .1 N o - - Da t e % D i ff. Me t e r Fl ow Co rr . f o r

M 301 Pre-t est Post - t e s t Fl ow s Cor r . Fac t o r Av g .

% Dif f

. Dat e % Di ff

.

5.4 Xact-IAP The Xact-IA P was turne d on prior to a tes t and continued operati on until the te st was com p leted. During Phase I and II tests, the Xa ct-IAP com p leted m o re than 730 runs and 9 daily upscale/blank checks. Sin ce no outliers were reported for the Xact-IAP and all flows m e t test plan objectives, all Xact -IAP data was accepted as reported.
The CES Xa ct-IAP was calibrated on Octobe r 8, 2004, two months before the Phase I evaluation. Upscale and blank c oncentrations (Table 9) were determ ined in Decem be r 2004. Upscale con centration s were determined autom a tica lly by th e Xact- I AP while blank concentratio ns were calculated b a sed on m easurem ents taken when spiking was not occurring and flue gas/ambient air was bei ng m easured. Overall, the Xact-IAP upscale concentrations were within 1% of the original calibration and the blank con centration s were below 2 μ g/dscm for all elem ents.

M e thod 301 E v al. : V1. 0 Section 5.0 Quality Con t rol and Assurance Page 38 of 75Table 9: Upscale and z e ro drift during Phase I testing.

Cr Cd H g Pb Cr Cd H g Pb
O r iginal Calibr a tion 11/11/2005 3260 4300 2789 1983 0.00 0.00 0.00 0.00 Av g. Conc

. P r e- T e s t 12/7/05 to 12/14/05 3250 4270 2784 1981 0.09 0.56 1.67 0.09 Av g. Conc

. Dur i ng T e s t 12/15/05 to 12/17/05 3270 4274 2789 1988 0.32 0.69 1.13 0.39 Pr e- T e s t /O r i g Cal. 12/8/05 to 12/14/05 1.00 0.99 1.00 1.00

- - - - - - - - T e s t /Or i ginal Cal. 12/15/05 to 12/17/05 1.00 0.99 1.00 1.00

- - - - - - - - Parameter D ate UP SCA L E B L A NK
E f

f e ct iv e mass/reg i o n μ g/dscm

The Xact-IA P XRF was calib rated us ing thin -f ilm standard s with NIST-tra ceable m e tal concentratio ns. These sam e standards were analy zed followin g Phase I an d II tests with the results show n in Table 10. Overall, the concentr a tions f o r th e m e tals rem a ined with in 5% of the or igina l calib ration f o r all m e tals. The two independent X acts, CES’ Xact for Phase I and Lilly ’s Xact for Phase II, were also in good ag reem ent, with concentration s within 5% of each other. For Phase II testing, the Lilly Xact-IAP wa s calibrated on J a nuary 28, 20 05, one m o nth prio r to the field evaluation. Upscal e and zero/blank drifts were de term ined in February 2005 and during the March tests with a summ ary shown in Table 11. Upscale co ncentration s were determ ined autom a tically by the Xac t -IAP while blank concentrations were calculated based on m easurem ents taken when spiking was not occurring and flue gas/ am bient air was being m easured. Overall, the X act-IAP showed ups cale and blank drifts below 4%, m eeting the criteria found in proposed Perform a nce Specification 10 20

. All m a ss and f l ow checks m e t QA precis i on r e q u irem ents a nd no Xact-I AP outliers were present during the 460 runs of Ph ase II testing. No changes were m a de to the reported XactIAP concentrations and no Xact-IAP data wa s removed from the original data set.
Table 10: Evaluation of NIST thin -film standa rds by the Xact-IAP.

P r e - Test P o st- T e s t P re -Test P ost- T e st 10/8/ 2004 3/28 /2005 1/28/ 2005 3/9/200 5 μ g / c m2 μ g / c m2 μ g / c m2 μ g / c m2 As 15207 12.50 12.17 0.97 11.92 12.52 1.05 12.33 12.22 1.0 1 C d 15207 8.25 8.14 0.99 8.27 8

. 32 1.01 8.20 8.30 0.9 9 Cr 15090 12.16 12.08 0.99 12.23 13.20 1.08 12.12 12.72 0.9 5 C o 15207 14.39 14.34 1.00 13.71 14.31 1.04 14.36 14.01 1.0 2 Se 15207 18.55 17.70 0.95 19.41 20.44 1.05 18.12 19.92 0.9 1 Hg 15102 16.50 16.00 0.97 15.73 16.18 1.03 16.25 15.96 1.0 2 Ni 15090 10.66 10.47 0.98 10.16 10.71 1.05 10.56 10.44 1.0 1 Tl 15090 11.36 11.17 0.98 10.84 11.49 1.06 11.27 11.16 1.0 1 S n 15090 14.41 14.32 0.99 13.86 13.92 1.00 14.36 13.89 1.0 3 Mn 15091 12.93 12.98 1.00 NM NM N M 12.96 NM N M C u 15091 11.77 11.79 1.00 NM NM N M 11.78 NM N M B r 15091 4.82 4.76 0.99 NM NM N M 4.79 NM N M Ba 15091 11.16 11.27 1.01 NM NM N M 11.21 NM N M Ag 15091 12.39 12.65 1.02 NM NM N M 12.52 NM N M F e 15092 14.05 13.62 0.97 13.39 13.80 1.03 13.83 13.59 1.0 2 Z n 15092 7.82 7.60 0.97 7.45 7

. 64 1.03 7.71 7.55 1.0 2 S b 15092 14.16 13.44 0.95 13.63 13.53 0.99 13.80 13.58 1.0 2 P b 15092 13.36 12.93 0.97 12.73 13.13 1.03 13.14 12.93 1.0 2 S r 15092 9.41 9.17 0.97 8.96 9

. 20 1.03 9.29 9.08 1.0 2
N M : Not Mea s ure d

El e m NIS T T r a cea b l e

St d N o . P H ASE I VS. P H AS E II P H ASE I : CES Xac t P H A S E II: L i l l y Xact

Po s t / Pr e Ra ti o Ratio P o st -T e s t/

Calib
. Av g Ph a s e I Av g . Phase II PI / P I I

M e thod 301 E v al. : V1. 0 Section 5.0 Quality Con t rol and Assurance Page 39 of 75Table 11: Upscale and zero drift d u ring Phase II testing

. Cr Cd H g Pb C r Cd H g Pb

Conc. Durin g Calib r ation 1 /2 8/2 005 181 2 4 30 3 3 4 4 7 5 0.0 0 0

. 0 0 0

. 00 0.00 Av g. C o nc

. Pr e - T e s t 1 1/29/05 to 3 / 1 / 05 185 5 4 29 3 4 6 4 8 8 0.2 3 0

. 6 0 0

. 05 0.09 Av g. C o nc

. D u r i n g T e s t 2 3/4 / 0 5 to 3/8/05 185 7 4 27 3 4 6 4 9 3 0.4 2 0

. 7 1 0

. 71 0.71 P r eT es t A v g. Cal. Drif t (%) 1 1/29/05 to 3 / 1 / 05 2.4

- 0.1 3 .5 2

. 9 0 .2 0.5 0 .1 0.1 Te s t A v g

. C a l D r i f t ( % ) 2 3/3 / 0 5 to 3/8/05 2.4

- 0.6 3 .5 3

. 8 0 .3 0.6 1 .2 0.2 1) Ups c a le av g. of 26 day s

. B l ank a v g

. of 2078 run s

. One blan k run (2/15/05 16:30:00) rem o v ed due to pos s i b l e s t a i nless s t eel c o nta m ina t io n f r o m s t a c k opera t i ons

. Pa rame ter D ate

2) Ups c a le av g. of 5 day s

. Bl ank av g. of 2 10 runs

. U PSC A L E B L A N K
E ffe ctiv e μ g/region μ g/dsc m



### 6.0 Results and Discussion
6.1 Overview This section summarizes the QAG, XFM, and Xact-IA P results from Phas e I and II tests. In Phase I, the QAG was validated by dem onstrating that it m e t all of th e criteria required in Method 301 and the study plan. It generated a ref e rence aerosol whose concentration f o r the f i ve test m e tals was linea r ly re la ted to the m easured concentration over the range from z e ro to120 μg/ds c m
. The QAG de m onstrated a p r eci s i on and stability of about 2% and an efficiency of 100% within the experim e ntal accuracy of the tests. These QAG validation results are summ arized in Subsection 6.2 and disc ussed relative to the validation criteria in Subsection 6.2.2. In Phase II, the XFM and Xact-IAP were evaluated for accuracy, precision , and linearity while sam p ling f l ue gas spiked with a m e tals-con tain ing ref e r e nce ae rosol f r om the QAG. The XFM and Xact-IAP m e t all Method 301 and test plan criteria, with precisions of better than 3% and a high linear correlation with the reference aerosol c oncentration. Phase II results for the XFM and Xact-IAP are summ ari zed in Subsection 6.3 and discussed as they pertain to the validation criter ia in S ubsections 6.4 and 6.5. The com p lete set of tes tdata and res u lts is li sted in Appendices I and J. S a m p le calculations are presented in Appendix K. 6.2 QAG Validation 6.2.1 Summary The prim ary objective of this phase was to vali date the QAG by dem onst r ating that it m e t the criteria in Method 301 and those established in th e test plan. During thes e tests, five m e tals (As, Cd, Cr, Pb, and Hg) were spiked at five concentration levels ranging from zero to over 120 μg/dscm. The QAG reference concentrat ions were verified by 146 Xact-IAP and 26 XFM analyses, with the three independent appro aches in goo d agreem ent for all five m e tals

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 40 of 75(Figure 12 and Table 12). All three independe nt approaches showed very good agreem ent over the wide range of concentrations and for all f i ve m e tals. Overall, the XFM to QAG and the Xact-IA P to QAG ratios were both 0.98 ± 0.07 (Figure 13). This good agreem ent between the QAG reference concentrati on and the XFM and Xact-IAP measured concentrations indicates that th e aerosol generation, transport and collection efficiencies were all essentially 100% within the uncertainty. The average XFM to QAG ratio for each of the five elem ents ranged from 0.94 to 1.00, while the Xact-IA P to QAG elem ental ratios ranged fro m 0.96 to 1.01. The consistency of the XFM/QAG and Xact-IAP/QAG ratios for individual elem ents confirm s the quantitative generation, transport and collecti on efficiency for each elem e n t. This sug g ests th at no significan t fractionation of m e tals to ok place du ring thes e tes t s. This is p a rticularly im portant because the metals represent both particle and vapor phases. Independent inductively-couple plasm a (ICP) analyses of the solutions conducted by Chester LabNet 21 of Tigard, OR confirm e d the inter-elem e nt concentra tion r a tio s
. It is im por tant to note that in all Phase I and II tests, the two m eas urem ent m e thods were totally independent from t h e QAG reference aerosol generato r as illustrated in Figure 2.

0 20 40 60 80 10 0 12 0 14 0 16 0QAGXFMXACTQAGXFMXACTQAGXFMXACTQAGXFMXACTQAGXFMXACT

H I G H MI D 2 MI D 1 L O W B L A N KConcentration (microgr/dscm) CR AS HG PB CD

Figure 12: QAG-generated and XFM- and Xa ct-IAP-measured aero sol concentrations during Phase I tests.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 41 of 75Table 12: Comparison of Average QAG ref erence aerosol concentrations w i th XFM and Xact-IAP average measured concentrations (μg/dscm). A ppr oa c h M e ta l B la nk Low M i d 1 M id 2 H igh QA G CR 0.0 19.8 50.3 6 5

. 0 128 AS 0.0 18.7 46.5 5 9

. 6 128 HG 0.0 20.0 50.9 6 5

. 7 129 PB 0.0 19.9 50.8 6 6

. 2 129 CD 0.0 19.9 50.7 6 5

. 4 129 X F M N o . 244 1 2 4 CR 0.1 20.2 42.2 6 5

. 5 130 AS 0.0 18.4 39.9 6 1

. 1 131 HG 0.7 18.7 42.3 6 3

. 7 120 PB 0.2 20.3 43.5 6 6

. 1 132 CD 0.5 21.1 46.0 6 5

. 7 128 X

A C T - I A P N o . 1 1 2 3 2 2 6 7 2 3 CR 0.1 19.8 42.0 6 5

. 7 131 AS 0.0 18.6 40.7 6 2

. 1 134 HG 0.7 19.8 43.1 6 4

. 9 128 PB 0.2 19.5 42.8 6 5

. 5 131 CD 0.6 19.6 41.7 6 5

. 2 126

0. 00 0. 20 0. 40 0. 60 0. 80 1. 00 1. 20

CR A S H G PB CDCandidateMethod/QAG XF M / Q A G XA CT / Q AG

Figure 13: Ratio of XFM and Xact-IAP meas u red meta l c o ncentratio ns to the QAG reference a erosol concentration. 6.2.2 Validation Criteria The QAG was validated by com p aring the QAG-genera ted reference aerosol concentration to the aerosol concentration m easured with the indep e n d ent, ana l ytically NIST- t raceab le XFM and Xact-IAP methods. The first step in this valid ation process was to dem o nstrate high relative transport and sam p ling efficiency for all test m e ta ls using m e tal concentration ratios. The second step was to dem onstrate high absolute genera tion efficiency by com p aring the QAG predicted reference aerosol concen tration with the analytically m easured aerosol concentration. The criteria used to dem onstrate high relativ e transpo rt and sam p ling efficienc y were:

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 42 of 75• Filte r Ratio : More than 98% of two representati ve particulate m e tals (Cr and Pb) were requ ire d to be on th e XFM’s f r ont f ilte r to d e m onstrate high particu l ate cap ture efficiency.

• Metal Ratio : A high transport and sam p ling effi ciency for vapor phase m e tals was assured by requiring the m easured m e ta l ra tio s be within 10% of the predic ted Q AG ratios. High absolu te efficiencywas then demonstrated by showing that the fo llo wing criter ia were m e t:

• Efficiency: The overall (generation, transport, and sam p ling) QAG e fficiency was required to be better than 80% for each m e tal as m easured by the XFM and Xact-IAP.

• Precis i on: The com b ined QAG and filter m easurem ent m e thod were required to have a precision of better than 10%.

• Linearity: The QAG was required to be linearly re lated to the two candidate m e thods with a correlation of better than 0.85.
6.2.3 Filter Ratio The objectiv e of this criterion wa s to dem onstrate that essen t ia lly all (>98%) of the Cr (low volatility m e tal) and Pb (sem i-volatile m e ta l) were captured on the upstream PTFE XFM f ilter. Meeting this ob jec tive dem onstra t es >98 % trapp i ng ef f i ciency f o r th ese two MACT m e tal catego r ies. The h i gh concentration XFM r uns (21 – 24) were the most sensitive tests for this evaluation. The results for these r uns are summarized in Ta ble 13. The average percent lead on the first f ilter for these high concentration runs was 99.9%, with no m easurable Pb or Cr found above their det ection lim it on the downstream filter. Sim ilar results were observed in Phase II where none of the Cr was measured on the downstream f ilter and the average Pb on the upstr eam f

ilter w a s m o re than 99%. Thes e high trapping ef

f i ciencies indica te th at all of the Pb and Cr were captu red b y the XFM’s PTFE f ilter and that this test plan cr ite rio n was m e t. Table 13: Lead and chromium mea s ured on the upstream PTFE filter as percent of total XFM lead and chromium (μg / filter ).

U p st re am Dow n st re am % Up st rea m Ups t rea m Dow n st re am % U p st re am Run No. μ g / f i l t er μg /f il ter μ g / f ilt er μg /f i l ter μ g / f i l t er μg /f il ter 21 3. 83 0.0 1 7 99 .6 3. 69 0. 00 0 1 00 .0 22 3. 63 0.0 0 0 1 0 0 .0 3. 62 0. 00 0 1 00 .0 23 3. 61 0.0 0 0 1 0 0 .0 3. 57 0. 00 0 1 00 .0 24 3. 76 0.0 0 0 1 0 0 .0 3. 72 0. 00 0 1 00 .0 A V E 3. 71 0.0 0 4 99 .9 3. 65 0. 00 0 1 00 .0 Ch r o m i u m Le ad

6.2.4 Metal Ratio The objectiv e of this criterion wa s to dem onstrate quantitative tr anspo r t a nd sam p ling efficiency for the other three MAC T m e tals (A s, Cd and Hg) with th e XFM and XACT-IAP. The m e tric for this com p arison was defined as the ratio of the Pb-norm a lized solu tion concentratio n to the

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 43 of 75Pb-norm a lized aeroso l concentration for these me tals. The reasoning is, if the Pb and Cr are quantitatively trapped by physical filtration as de monstrated above, and if the ratio of the other elem ents to Pb for the XFM and Xact-IAP is the sa m e as in the nebulized solution, then the total sam p ling and transpo r t e f f i ciency f o r these m e tals as m easured with the X F M f ilter ca ssette is the sam e as that for Pb, i.e., 100%. The accep table range for this ratio was defined in the test plan as 0.9 to 1.1. The average m e tal ratios ranged from 0.99 to 1.05 for the XFM and 0.96 to 1.01 for the XactIAP. These m e tal ratio v a lues a r e c l e a rly within th e range def i ned in the test plan. As such, this criter ion was m e t. Meeting this and the pre cedin g f ilter ratio criter ia demonstra t es tha tthes e m e tals do not fractionate during generation, transport and m easurem ent of the reference aerosol. 6.2.5 Efficiency Efficiency is defined as the ratio of the m eas ured aerosol concentra tion to the QAG-predicted reference aerosol concen tration expressed as a percent. This efficiency includes the QAG generation efficiency as well as the transpor t and m easurem ent efficiencies. This to tal system efficiency for five m e tals m e asured at four concentration levels during Phase I QAG validation testing are listed in Table 14. Th e average QAG efficiency over all five metals and all four concentration levels was 97.8± 2.3% and 97.7±1.8% as m easured by the XFM and Xact-IAP, respectively. This represents all 24 XFM and 142 Xact-IAP individual efficiency determ inations. The average QAG effi ciency for each m e tal as m easured with the XFM ranged fro m a low of 94% fo r Hg to a high of 100% for Cd. The average QAG efficiency for each m e tal as determ ined with the Xact-IAP ranged from a low of 96% for Cd to a high of 101% for As. In addition, the QAG effi ciencies at low and high concentrations as determ ined with both candidate analytical m e thods were greater than 99%, which dem onstrates that efficiency is independent of aerosol concentr ation in the range from 20 to 125 μ g/dscm. Thus, the average total system efficiency (gener ation, transport and m easurem ent) is 98 ± 2 % . However, the unce r ta inty in the r e f e rence ae ro sol concen tr ation was about 4%. As such, the test plan crit erion was m e t, the measured efficiency was essentially 100% within the uncertainty, and no efficiency correction fa ctor is required. A com p lete set of results a nd sam p le calculation s u s ed f o r these ef f i ciency d e term ination s are presented in Appendices I and K.
6.2.6 Precision QAG precision m easurem ents are summarized in Tabl e 15. This table lists the precision for each elem ent as determ ined for each con c entration le vel, and are based on se quential m easurem ents. The average QAG precision over all elem ents and a ll concentration levels was better than 2.5%, significan tlybetter than the required 10% criter ia value. The high pr ecision at each le vel dem onstrates the ability of the QAG to m a intain a constant concentration over extended periods of tim e. The s e precision results are based on data listed in Appendix I with sam p le calculations provided in Appendix K.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 44 of 75Table 14: QAG efficien cies determined during Phase I laboratory tests (% ).

R U N C R H G A S C D P B C R H G A S C D P B

1 10 0 9 7 1 03 10 0 9 8 1 02 1 0 1 1 0 1 98 1 0 0 2 10 0 9 9 1 02 9 8 98 9 3 9 9 10 0 9 9 9 3 3 1 0 1 9 7 1 0 3 98 9 8 98 94 1 0 1 104 99 4 99 9 8 10 4 1 03 9 7 99 97 1 0 0 9 8 1 0 0 5 1 0 1 100 10 7 1 01 9 9 10 1 1 0 0 1 0 5 9 9 9 8 6 1 0 3 9 9 1 0 3 98 101 10 1 1 0 0 1 0 3 104 10 1 7 1 0 3 9 9 1 0 7 1 0 2 101 10 2 9 8 1 01 9 8 10 2 8 1 0 4 101 10 7 1 00 100 10 1 9 7 1 04 9 9 99 9 1 0 0 9 9 1 0 3 98 9 9 10 2 9 0 1 03 100 10 2 10 1 0 1 9 9 1 0 4 97 9 8 10 3 9 6 1 04 102 98 11 1 0 3 9 9 1 0 3 98 101 10 9 1 0 2 1 1 1 105 10 9 12 1 0 0 9 9 1 0 4 1 0 2 9 9 9 8 9 2 9 7 9 8 9 8 13 83 8 6 88 76 8 3 83 80 83 8 9 87 14 84 8 4 87 84 8 5 85 84 88 8 7 87 15 82 8 5 87 84 8 5 83 86 85 9 9 85 16 84 8 4 88 85 8 5 84 83 87 8 8 84 17 98 101 10 0 9 6 9 6 1 0 2 95 96 105 10 0 18 10 3 9 8 1 02 10 3 9 5 1 04 9 3 10 2 1 0 6 9 9 19 1 0 1 102 10 1 1 00 9 9 10 0 9 3 9 8 103 10 5 20 99 9 6 96 96 101 10 4 9 4 9 8 111 10 4 21 1 0 3 100 10 6 9 7 100 10 1 1 0 0 1 0 1 9 9 1 0 4 22 1 0 2 9 9 1 0 4 1 0 0 102 10 3 9 5 1 04 100 10 3 23 1 0 2 100 10 4 9 6 103 10 0 8 8 1 02 9 8 10 0 24 1 0 3 100 10 6 9 9 102 10 2 9 0 1 03 101 10 2 A

v g . 98 .2 9 6

. 7 10 0. 8 9 6

. 3 9 6. 7 98. 4 9 3

. 6 9 9

. 0 9 9. 6 98. 2 SD 7. 0 5

. 6 6

. 5 6

. 9 6. 0 7 .3 6. 0 6

. 8 5. 5 6 .5 %S D 7. 1 5

. 8 6

. 5 7

. 2 6. 2 7 .4 6. 4 6

. 9 5. 5 6 .6 Xact Det e rmi n ed QA G Ef fici ency XFM Determ ined QA G Eff i ci en cy

Table 15: Summary of QAG Phase I precis i on ( % ).

L o w M id 1 M id 2 H i g h Low M i d 1 M id 2 H i g h Ru n s 17- 20 Runs 13 - 1 6 Runs 1- 12 Runs 21- 24 R uns 17- 20 R uns 13- 16 Runs 1- 12 Runs 21 - 2 4 (% ) ( % ) ( % ) ( % ) (% ) ( % ) (% ) ( % ) (% ) ( % ) CR 1.3 1 .0 2.3 0 .9 1.4 1

. 7 1 .0 1.1 0 .3 1.0 AS 1.8 2 .0 2.2 1 .1 1.8 2

. 0 0 .6 1.0 0 .7 1.1 HG 0.8 2 .1 2.8 3 .7 2.3 2

. 0 1 .0 0.7 0 .6 1.1 PB 1.7 1 .3 2.2 0 .8 1.5 2

. 0 0 .8 0.8 1 .1 1.2 CD 2.3 4 .1 1.9 1 .0 2.3 2

. 5 3 .4 1.5 1 .2 2.1 A

V G 1 .6 2.1 2 .3 1.5 1 .9 2

. 0 1 .4 1.0 0 .8 1.3 ELE M XF M XA C T
AV G

. AV G

.

6.2.7 Linearity The test p l a n linea rity cr ite rion f o r v a lida ti on acceptance was a correlation coefficient ( r ) value greater than 0.85. The QAG linearity was de term ined from a regression analysis for a plot of the m easured aerosol concentration versus the QAG-pred icted reference concentration over four concentration levels and a blank level. These plot s for both the XFM and the XactIAP are illustrated in Figure 14 and F i gure 15 (Note that only r 2 , coefficient of determ ination, values are listed in these plots). S i nce all of the r 2 values are greater than 0.99, the r values are also greater than 0.99 and thus clearly m eet th e test plan acceptab i lity requirem e nt for r. Other linearity defining factors such as slope and intercept w e re also determ ined and are supportive. As can be seen from the plots in these two figures, the slopes ranged from a low

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 45 of 75of 0.94 for Hg as m easured with the XFM to a high of 1.05 for As m easured with the XactIAP. The overall average slope was close to 1.00 verifying the strong agreem ent between these independent approaches. Inaddition, the intercepts were all below 2% of the full scale indicating a low blank bias. It is also important to note th at none of the data was excluded in these linearity plots. In the case of the XFM, results from all 26 runs are included. The Xact-IAP ran continuously during the three days of Phase I tests and com p leted m o re than 270 runs, of which 146 were conducted w h ile the QAG was in operation. A ll 146 Xact-IA P runs that corresponded to QAG runs are included in the plots shown in Figure 15. The Xact reported no outliers, experienced no m echanical prob lem s , and had an effective upt im e of 100% during Phase I. This strong linear relationshi p between the concentrations m easured with the candidate m e thods and the independent QAG-generated ref e rence aerosol concentration dem onstrates the ability of the QAG to spike quantitativ ely over a wide range of concentrations.

CHRO M I UM

y = 1

. 02 3x - 2. 0 5 1 R 2

= 0. 990 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 1 00 120 14 0 Ref e r e nc e Co nc

. ( μ g/ d s c m )XFMConc.(μg/dscm) n= 2 6

M E RCURY

y = 0. 941 x - 0

. 0 5 4 R 2

= 0

. 9 8 7 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 100 120 140 Re f e r e nc e Co nc

. ( μ g/ d s c m )XFMConc.(μg/dscm) n= 2 6 ARS E N I C

y = 1. 0 3 9 x - 2. 11 9 R 2

= 0. 99 3 0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 1 4 0 Re f e r e nc e Conc

. ( μ g/ ds c m )XFMConc. (μg/dscm)

n= 2 6

C ADM I U M

y = 0

. 99 5x - 0. 1 3 4 R 2

= 0

. 9 9 5 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 1 00 1 2 0 1 40 Re f e r e nc e Con c

. ( μ g / ds c m )XFMConc. (μg/dscm)
n= 26 LE A D

y = 1. 03 0x - 2

. 4 8 9 R 2

= 0. 992 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 1 4 0 R e f e r

e nc e C o n c

. ( μ g/ d s c m )XFMConc.(μg/dscm)

n= 2 6

Figure 14: Phase I QAG linea rity pl ots as determined by the XFM.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 46 of 75CHRO M I UM

y = 1. 019x - 1. 4 2 1 R 2 = 0. 99 3 0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 1 0 0 12 0 140 Ref e r enc e Conc

. ( μ g/ ds c m )XactConc.(μg/dscm) n = 146 ARS E N I C

y = 1. 0 47x - 1. 600 R 2

= 0

. 993 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 100 12 0 140 R e f e r e nc e Co nc

. ( μ g/ ds c m )XactConc.(μg/dscm) n = 146

M E RCU RY

y = 0. 9 79x - 0. 542 R 2

= 0

. 993 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 100 120 14 0 R e f e r e n c e Co nc

. ( μ g / ds c m )XactConc.(μg/dscm) n = 146

CAD M I UM

y = 0. 983x - 0. 762 R 2

= 0

. 9 9 0 0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 100 12 0 1 4 0 Ref e r enc e Conc

. ( μ g/ ds c m )XactConc.(μg/dscm) n = 1 4 6 LEA D

y = 1. 002 x - 1. 33 5 R 2

= 0

. 9 9 2 0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 1 4 0 R e f e r e nc e Co nc

. ( μ g/ ds c m )XactConc.(μg/dscm) n = 146

Figure 15: Phase I QAG linea rity plots as determined w i th the Xact-IAP 6.2.8 QAG Validation Summary and Recommendation Phase I results as they pertai n to the QAG validation criteria are summ arized below in Table 16. It is clear from this summary that all QAG validation criteria established in the test plan were m e t. As such, the QAG shoul d be approved as a reference aerosol generator that can be used for validating em ission m easurem ent instrum e nts and methods including CEMS, IAP, alternatives to reference m e thods and conditional m e thods. Table 16 Summary of P h ase I QAG validation results.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 47 of 75 Crite r ia A c ce pta b l e Res u l t s a Me t Cri t e r i a No. Run s > 9 >25 Y e s F i l t er R a t i o (% F r on t) > 9 8 > 9 9 Y e s M e t a l R a t i o ( S ol ./ Ae r. ) 0 .9 - 1

. 1 0

. 9 5 - 1

. 01 Y e s b Ef

f i c i en c y( % ) > 80 9 4 - 10 0 Y es Pr ec i s i o n ( % ) < 10 < 4 Y e s Lin e a r ity - Co rr. Coe f

. ( r ) > 0.8 5 >0 .9 9 Y e s

a X F M and X a c t res u l t s f o r al l fi ve e l em ent s b C o nfi r me d w i th i nde pe nd ent IC P an al y s i s re s u l t s6.3 XFM and Xact-IAP Validation Overview The prim ary objective of Phase II tes ting was to validate the XFM and Xact-IAP by dem onstrating that they m e t the condition a l m e thod criteria estab lished in the test plan. The QAG, validated in Phase I, was used in this phase to spike a NI ST-traceable reference aerosol into incinerator flue ga s. As such, it is assum e d that the characteristics of the QAG reference aerosol generator ar e those dem onstrated in Phas e I; i.e., 100% generation and transm ission efficiency. Valid ation criteria and acceptan ce v a lues are th e sam e for both the XFM and the Xact-IAP, and include bias, precis ion and linearity. Phase II results and test conditions are listed in Appendi x J and sam p le calculations are provided in Appendix K. The general results from Pha s e II te sting for both the XFM and Xact -IAP are summarized below. The detailed XFM results as they pertain to th e s p ecific valid ation criteria are presented in Subsection 6.4 while the results for the X act-IA P are presented in Subsection 6.5. It needs to b e em phasized that:

• The QAG, XFM and Xact-IAP were independe nt of each other in Phase II as they were in Phase I. That is, the QAG wa s not used to calibrate the XFM and the Xact as is comm onl y accepted p r actice in EPA instru m e ntal an alyzer procedures s u ch as Methods 6C and 7E where the sam e gas standard used to calibrat e the instrum e nt is used to spik e the s t ack g a s. The XFM and Xact-IAP results are bas e d onNISTtrac eable thin f ilm standards.

• The Xact instrum e nt used in Phase II was not the sam e one us ed in Phase I. As such, the Xact us ed in Phase II was calib rate d independently of the Phase I Xact.

• Results from all of the runs were used for the data analysis. In som e cases, data from som e runs could have been excluded, wh ich would have resulted in a significant im prove m e nt in the agreem ent between the m e thods. However, even when all the data is inc l u d ed, all of th e valid ation criter ia ar e s till m e t. Phase II testing consisted of spiking stack gas with a QAG-generated ref e rence aerosol containing five elem ents (As, Cd, Cr, Hg, and Pb) at three concentra tions ranging from about 20 to 120 μg/dscm and at a blank level. The concentration of the QAG-spiked stack gas and the m easured XFM and Xact concen trations are summ arized in Table 17 and Figure 16. Concentrations reported by the XFM and the X act-IAP were in good agreem ent with each other and with the reference aeros ol concentratio n at all th ree spiked concentrations and the blank. Overall, the XFM to reference aeros ol concentration ratio was 1.02 ± 0.07 while the Xact-IAP ratio was 0.93 ± 0.07.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 48 of 75Table 17: Summary of XFM and Xact-IAP me asured concentrations and QAG-spik ed flue gas con centrations Phase II (μ g/dscm).

A p pr o a c h A vg. Bl a n k A vg. Lo w A vg. Mi d A vg. Hi g h N u m b e r 4 4 6 1 2 C R 0. 0 21. 3 46. 2 108 A S 0. 0 21. 2 46. 2 108 H G 0. 0 21. 2 45. 9 108 P B 0. 0 21. 2 45. 9 108 QAG
C D 0. 0 21. 2 46. 2 107 C R 0. 2 22. 9 41. 8 112 A S 0. 0 21. 7 41. 0 114 H G 0. 3 22. 7 40. 2 111 P B 0. 9 22. 6 40. 6 115 XF M
C D 0. 3 22. 3 43. 1 113 C R 0. 0 20. 0 37. 8 103 A S 0. 1 21. 0 39. 9 107 H G 0. 2 18. 5 35. 2 95 P B 0. 0 18. 8 37. 9 108 XACT
C D 0. 3 21. 5 39. 9 106

M e t hod 301 R e port ed Concent r at ions

0 20 40 60 80 100 120 140QAGXACTXFMQAGXACTXFMQAGXACTXFMQAGXACTXFM

HI GH M I D L OW BLA N KConc. (μg/dscm) CR AS HG PB CD

Figure 16: Comparison of the XFM and Xac t-IAP measu red concentrations w i th the QAG-spiked flue gas concentrations during Phase II testing.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 49 of 756.4 XFM Validation
6.4.1 Bias The twelve high concentration runs were used to calcu late b i as with results shown in Table 18. Overall, there is very good agreem ent between the XFM m easured concentration and the reference aerosol concen tration with an average bias over all m e tals of 4.8±1.3%. Mercury exhibited the lowest bias at 3.1% and Pb th e highest at 6.3%, which are all below the 10% acceptance criterion.Thu s, the XFM m eets the requi red b i as criteria for all m e tals tested. Table 18: Summary of XFM Phase II bias valu e s for ea ch metal tes t e d (μg/dscm).

Re fe re nc e R u n C oncentrat ion C R A S H G P B C D C R A S H G P B C D

1 108 113 112 109 114 113 5.36 4.40 1. 38 5. 80 5.22 2 108 114 117 108 118 118 6.54 9.00

- 0 .21 9

. 5 7 10. 46 3 108 111 113 114 110 110 2.66 5.29 5. 52 2. 20 2.48 4 108 112 113 104 113 113 3.80 4.75

- 3 .97 4

. 6 3 4 .79 5 108 111 112 109 120 114 3.38 3.76 0. 67 11.58 5.91 6 108 114 116 117 116 112 5.63 8.17 8. 66 8. 29 4.40 7 108 110 112 113 111 112 2.30 4.39 4. 52 3. 34 4.37 8 108 104 110 117 112 104

- 3 .63 2 .15 9

. 1 3 3

. 8 9

- 3

. 58 9 108 109 110 109 109 113 0.70 2.49 0. 69 0. 61 4.96 10 108 116 114 108 124 113 8.50 6.40 0. 09 15.90 5.23 11 108 117 121 120 117 119 9.58 13. 0 6 11.44 9. 20 11. 16 12 108 113 116 111 115 117 5.30 7.70 2. 84 6. 86 8.87 A

V G 108 112 114 111 115 113 4.18 5.96 3. 40 6. 82 5.35 SD 3

. 5 3 .1 4

. 6 4 .3 3

. 8 3

. 5 4 3

. 1 0 4 .5 6 4 .3 4 3

. 8 5 XFM SD 2.50 2.20 3.22 3.07 2.72 2.50 2.20 3. 22 3. 07 2.72 XF M S D M 0.72 0.63 0.93 0.89 0.79 0.72 0.63 0. 93 0. 89 0.79

% B i a s 3.87 5.52 3. 14 6. 32 4.96 XFM X FM B i as (XFM- R eference)

6.4.2 Precision The average XFM precision (PRSD) based on the XFM standard deviations (XFM SD) listed above in Table 18 was 2.5±0.4% and ranged from a low of 2.0% for As to a high of 3.0% for Hg. This rep r esents a sig n ificant im provem e nt over the curren tly accepted precis i on for Reference Method 29 and well with in the 10 % criterion acceptance value required for validation. 6.4.3 Linearity The key line a rity cr ite rio n f o r the XFM is a co rrelation co efficient ( r ) value greater than 0.85. To test the linearity of the XFM, the flue gas was spiked withall f i ve m e tals a t f our re f e rence aerosol concentrations using the QAG. The results from these five test s are plotted in Figure 17. A least-squares regression analysis of all 26 data points pr ovided the correlation coef f i cient a s well as the slope and in terc ept f o r e ach m e tal. All of the co rrelation coefficients were greater than 0.99, easily exceed ing the requirem e nt to be greater th an 0.85. The slopes averaged 1.06±2 and ranged from a low of 1.04 for Hg to a high of 1.07 for As and Pb. The intercepts were less than 3% of the full scale indicati ng low blank values.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 50 of 756.4.4 XFM Summary Phase II XF M results are summ arized in Table 1 9. This tab l e shows that all the acceptance criter ia were m e t f o r all of the f i ve MACT m e ta ls tested. As such, it is recommended that the XFM be approved as a condition a l method.

Me r c u r y

y = 1.036x - 1.803 R 2 = 0.991 0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 100 120 140 R

e f

e r e nc e C onc . ( μ g/ ds c m )XFM(μg/dscm) n= 2 6 Ch r o m i u m

y = 1.042x - 1.605 R 2 = 0.994

0 20 40 60 80 10 0 12 0 14 0

0 2 0 4 0 6 0 8 0 100 120 140 R e fe r e nc e C onc . (μ g/ ds c m )XFM(μg/dscm) n= 2 6 Ar s e n i c

y = 1.067x - 2.716 R 2 = 0.994
0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 100 120 1 4 0 R

e f e r e nc e C onc . ( μ g/ ds c m )XFM(μg/dscm) n= 2 6

Le a d

y = 1.068x - 2. 079 R 2 = 0.991 0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 100 120 140 R

e f e r e nc e C onc . ( μ g/ ds c m )XFM(μg/dscm) n= 2 6

Ca d m i u m

y = 1.054x - 1.613 R 2 = 0.994
0 20 40 60 80 100 120 140

0 2 0 4 0 6 0 8 0 100 120 140 R e f e r e nc e C onc . ( μ g/ ds c m )XFM(μg/dscm) n= 2 6

Figure 17: Phase II XFM linearity.

Table 19: Summary of Phase II XFM va lidat io n test cr it er ia and results. C r iter ia A cce pt able R esult s a Me t Cri t e r ia No . Ru ns >9 2 6 Y e s Bias Co rr

. Fa ctor 0.8 0

- 1.2 0 .94 - 0.97 Y e s b Pr eci s io n ( % ) < 10 < 3 Y e s Lin ear ity

- Co rr

. C o e f . ( r ) > 0.85 > 0 .9 9 Y es

a X F M r e sult s f o r a ll fiv e ele m en ts
b C o nf irme d w i th inde pe nde nt IC P a naly s is re sult s

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 51 of 756.5 Xact-IAP Validation
6.5.1 Xact-IAP O verview The Xact multi-m etals analyzer, when perm anently installed, acts as a CE MS, wherea s if it is installed for short term em ission m easurem ents (days to weeks), it is part of an IAP. It is this latter application that is the focus of this subsection. Two di fferent Xact instrum e nts were used during Phase I (CE S Xact) and Phase II (L illy Xact) tes t s, re quiring two independent calibrations using NIST traceab le thin-f ilm standards. All of the va lida tion c r ite r ia wer e m e t f o r all of the elem ents. However, as discussed below, a key issue is whether or not to apply a bias corre ction factor if a significant bias is observed.
6.5.2 Bias The twelve high concentration runs (nom inal concentration of 110 μ g/dscm ) were used to calculate bias. These bias results along with the m easured Xact-IAP resu lts and the reference aerosol concentration are listed in Table 20 along with standard deviations and percent bias. As can be seen from this table, there is very good agreem ent betweenthe Xact-IAP measured concentratio ns and the reference aero sol concen tration for a ll the elem ents. Method 301 requires an evaluation for bias in the candidate method in order to determ ine if a correction factor is required 1 . For Phase II tests, bias was determ ined by evaluating the system atic differences between the reference ae rosol m e thod and candidate m e thod relative to the uncertainty in the methods. Bias was considered to be significant when it exceeded two tim es the com b ined uncertainty in the reference generation and candidate m easurem ent m e thod at the 95% confidence level. Since the com b ined Xact-I AP and QAG uncertainty is on the order of 5%, the sign if ica n ce cr ite ria r e sulted in a 10% thre sho l d for determ ining the significance of bias. Four of the elem ents m easured by the Xact-IAP – As, Cd, Cr, and Pb – had biases of less than 2%, well within the uncertainty of the m e thods and below the threshold of significance. For this reason, no correction factor is requ ired for As, Cr, Cd, or Pb. The average percent bias for Hg was 12.3±1.0%. This bias is clearly above the 10% level of significan ce f o r the QAG/Xact-IAP, but well within the acceptable ra nge of 30% specified in Method 301; particularly with the high precision (±1%) observed for this bias. Although a correction m i ght be considered necessary, it is not recomm ended in this case as is disc ussed in detail in the following subsection. 6.5.3 Mercury B i as Correction Factors As noted above, a significant, system atic bi as g r eater th an 1 0 % was obs erved in the Hg results from Phase II tests of the Xact-IAP. However, even though the percent bias (12.3%) was greater than 10%, it is recomm ended the Xact-IAP be approved without the requirem e nt of a bias correction facto r , sin ce h a lf of the bias was due to a post-test ide n tif ied ca lib ration error. Th is error was id entif ied by e v aluating th e Hg/Pb sensitiv ity (ca l ibration) r a tio, which is used to ob tain NIST traceability th rough the Pb concentration in NIST SRM 1833. This ratio should have been 0.93, but was instead 0.99. If this 6% e rror had not existed, the XactIAP Hg results would have been 6% higher and the Hg percent bias would have been about 6%, well within the required 10%.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 52 of 75Table 20: Comparison of Xact-IA P w i th QAG reference concentrations and bias (μg/dscm). Ref

. Run C onc . C R A S H G P B C D C R A S H G P B C D

1 108 105 1 0 6 9 4 102 1 0 6

- 3. 07 -2. 1 1

- 14 .44

- 5

. 65 -1. 5 7 2 108 103 1 0 6 9 6 104 1 0 5

- 5. 26 -2. 0 1

- 12 .44

- 3

. 84 -2. 5 1 3 108 102 1 0 6 9 5 105 1 0 6

- 6. 14 -1. 8 8

- 12 .74

- 3

. 17 -1. 9 3 4 108 102 1 0 5 9 4 107 1 0 5

- 5. 77 -2. 7 5

- 14 .24

- 1

. 02 -2. 7 8 5 108 100 1 0 6 9 4 105 1 0 5

- 7. 94 -2. 0 6

- 14 .22

- 2

. 55 -2. 6 2 6 108 103 1 0 7 9 4 110 1 0 5

- 4. 92 -1. 4 5

- 14 .19 1 .76

- 2. 26 7 108 103 1 0 7 9 5 111 1 0 9

- 5. 08 -1. 3 3

- 13 .18 2 .98 1 .61 8 108 103 1 0 7 9 4 109 1 0 7

- 4. 64 -1. 2 8

- 13 .68 1 .44

- 0. 54 9 108 105 1 0 8 9 5 110 1 0 6

- 2. 54 0. 05 -13

. 08 1.65 -1. 4 1 10 108 104 1 0 7 9 4 109 1 0 5

- 4. 10 -1. 0 2

- 14 .12 1 .37

- 2. 89 11 108 107 1 1 0 9 7 111 1 0 7

- 1. 07 2. 27 -11

. 29 2.99 -1. 1 3 12 108 105 1 0 9 9 7 112 1 0 6

- 2. 44 1. 43 -11

. 32 3.74 -1. 3 0 A

V G 108 103 1 0 7 9 5 108 1 0 6 - 4. 41 -1. 0 1 - 13 .25 - 0

. 02 -1. 6 1 SD 1. 9 1 .5 1. 1 3

. 1 1.3 1 .89 1

. 5 2 1

. 1 2 3 .10 1 .25 Xact SD 1.34 1. 07 0.7 9 2. 19 0. 89 1

. 34 1. 07 0. 79 2.19 0

. 89 Xact SDM 0.39 0. 31 0.2 3 0. 63 0. 26 0

. 39 0. 31 0. 23 0.63 0

. 26

% Bi as -4. 0 9 - 0. 93 -12

. 27 -0 .02 - 1. 49 Xact XA CT-QA G

This type of error did not appear in Phas e I testing using CES’ Xact which had been calib rated with th e appro p ria t e Hg/Pb sensitivity r a tio. For Ph ase I, th e Hg bias was le s s than 2% for the 12 runs near the em ission lim it and was less than 4% averaged over all of the 146 Xact-IAP measurem ents

. This error is readily correctable within the Xact software and should not be present in future tests. As such, it is recommended that no corr ection factor be m a de to future Xact-IAP m e rcury m e asurem ents. 6.5.4 Precision The average Xact-IAP p r ecis i on (PR S D) based on th e Xact-IAP standard deviations (Xact SD) listed above in Table 20 was 1.3 ± 0.6% and ranged from a low of 0.8% for Hg to a high of 2.0% for Pb. This repres ents a significan t improve m e nt over the currently accep ted precis io n for Reference Method 29 and substantially less than th e required validation acc eptance lim it of 10%. 6.5.5 Linearity The Xact-IA P ran continuously during the five days of Phase II tests and com p leted more than 450 runs, of which 192 were conducted while the QAG was operated. The Xact-IAP experienced no m echanical problem s during Phas e II testing and had an effective uptim e of 100%. To test the linearity of th e Xact-IAP, the incinerator flue gas was spiked with all five m e tals at four reference aerosol concentrations using the QAG. The results from these tests, including a series of blank runs, are plotted in Figure 18. A least-squa res regression analysis of all 192 data points provided the correlation co efficient as w e ll as the slope and intercept for each m e tal (The co efficient of determ ination, r 2 , is listed on the figures.) All of the correlation coefficients ® were greater than 0.99, easily exceeding the required lower lim it value of 0.85.

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 53 of 75Ch r o m i u m

y = 0. 9 52x - 1. 1 2 9 R 2

= 0. 994 0 20 40 60 80 100 120

0 2 0 4 0 6 0 8 0 100 120 R e f e r e n c e C onc . ( μ g/ds c m )XactConc.(μg/dscm)

n = 192

Mer c u r y

y = 0. 8 70x - 0

. 825 R 2 = 0. 99 6 0 20 40 60 80 100 120

0 2 0 4 0 6 0 8 0 100 120 R e f e ren ce C o n c . ( μ g / d scm)XactConc.(μg/dscm)

n= 1 9 2 A r sen i c

y = 0. 9 83x - 1. 037 R 2 = 0. 995 0 20 40 60 80 100 120

0 2 0 4 0 6 0 8 0 1 0 0 1 2 R e f e r e nc e C onc . ( μ g/ds c m )XactConc.(μg/dscm)

n = 192

0

Lead

y = 0

. 991x - 1

. 924 R 2

= 0. 99 2 0 20 40 60 80 10 0 12 0

0 2 0 4 0 6 0 8 0 1 0 0 1 2 0 R e f e ren ce C o n c . ( μ g / d scm)XactConc.(μg/dscm) n = 192

Ca d m i u m

y = 0. 9 71x - 0. 845 R 2

= 0. 993
0 20 40 60 80 100 120

0 2 0 4 0 6 0 8 0 100 120 R e f e r e n c e C onc . ( μ g/ds c m )XactConc. (μg/dscm) n = 192

Figure 18: Phase II Xact linearity.
6.5.6 Xact-IAP Summary and Recommendations The Phase II Xact-IAP results are summarized in Table 21 and Tabl e 22. Table 21 shows that all the acceptan ce cr iteria were m e t for all of the five MACT m e tals tested. Onlyone m e tal, Hg, m i ght have required a bias correction factor. Howeve r, it is r ecomm ended that the procedure b e approved without a co rrection f actor because, as discussed in Subsection 6.5.3, the significant bias observed wa s due to a calibration error, was not observed in Phase I, and should not h appen in future applications because of changes m a de to the software an d SOP. Table 22 compares the Xact-IAP results fr om Phase II with proposed Perform a nce Specificatio n 10 for m u lti-m e tals CE MS. It is clear from the com p arison, that all of th e criteria in this proposed perf orm a nce specification were m e t. Table 21: Summary of Phase II Xact results. Criteri a A c c e ptable Res u l t s a Me t Cr i t e r i a No. Runs >9 19 2 Y e s Bias Corr. Factor 0

. 80 - 1.2 1 .0 0 - 1

. 14 Y e s Preci s io n (%) < 10 < 3 Y e s Lin earity - Corr. Co ef . ( r ) > 0.8 5 > 0

. 9 9 Y e s

a X a ct

- I AP r e su lt s f o r a ll fiv e e l e m e n t s

M e thod 301 E v al. : V1. 0 Section 6.0 Results and Discussion Page 54 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Table 22: Comparison of Xact Phase II resu l ts w i th proposed PS-10 criteria.

UN IT S XAC T PS -1 0 C r it e r ia M E T P S -10 Cr it er ia U p time % 100 N A Y es Me tals Mea s ure d Dur i ng Testing

- - 5 2 Y es Re sp on se Time min. 4 5 24 0 Y es Reporting Time min

. 15 6 0 Yes U p sca le /C a libr a tion Dr if t % < 4 5 Y es Z e r o /B la nk Dr if t % < 2 5 Y es Pr e c ision (PRSD ) % < 4 1 5 Y es No. o f Me as ur em en t s - - 20 9 Y e s R e l a t i ve A ccur a cy % 2 -1 6 2 0 Y e s CR ITERIA

* Com p arison to EPA Method 29' s typical precision of 15%.



### 7.0 Range of Method Application
7.1 Overview The results from the preceding sectio n clearly demonstrate th e ability of the XFM and XactIAP to accurately and precisely quan tify m e tals in stack em issions over a broad rang e of concentrations, and that these m e thods are appli cable to the quantitative measurem ent of the five validated m e tals in hazardous w a ste inci nerators. The qu estion then arises as to What other source categories and elements is this technology applicable? The answer to this qu estion lies in how key features of the sa mpling and analysis procedures depend on and respond to changes in em ission charac teristics associated w ith different source categories. The EPA suggests in Method 301 that this m i ght be addressed in part by conducting a series of ruggedness tests, which ar e laboratory tests of a m e thod’s sensitiv ity to key m e thod variables 1
, 29, 30 . This type of evaluation of the XFM and Xact-IAP was conducted during Phase I laboratory testi ng. In addition, a substantial b ody of previous laboratory and field test data on this reactiv e-filter based technology is also available that supports the general applicability of these m e t hods to m o st sources and elem ents. The above tests and data are summ arized in th is section along with key aspects of the XFM and Xact-IAP m e thods, and relative characteri stics of e m issions. The objective of this review is to dem onstrate that these m e thods should be considered generally applicable to a wide range of e m issions and elem ents including those from re gulated sources. This review is presented in the f o llowin g subsection s :

• Method Applicability (7.2)

• Key Sa m p ling and Analysis Features (7.3)

• Key Em ission Character istics (7.4)

• Filter Trapp i ng Efficiency for Vapor Phase Metals (7.5)

• Applicable Concentration Range (7.6)

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 55 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s • Deposit Sta b ility (7.7 )

• Moistu re (7. 8 )

Page 56 of 75 ( 7

. 9 )

. 1 0 )

G a s e s ( 7

. 1 2 )
T h e x L a n d s u p p o r t i n g r e p o r t s a r e p r o v i d e d i n Appendix M. The conclusion of this review is that there is a substant ial body of inform ation

qu i r e m e nts of Method 301, it is valid for the source tested, and m a y be applicable to the specific source category. Method 301
i t e r i a

r e t r a t i o n s
.

n t a tive sam p le of stack gas through a filter m a trix where m e tals are concentrated prior to analysis. The X F M draws th e stack g a s

a n d ,
( C )

c k • Holding Tim e s

• O t h e r R e l a t e d T e s t s ( 7

• Applicable Elem e n t s ( 7

. 1 1 )

• Sensitiv ity to Reactive S t a c k d e t a i l s o f t h i s r e v i e w a r e p r e s e n t e d i n A p p e n d i
about the chem istry and physics of the m e thods and em issions as well as specific test data covering som e of the more cha llenging of conditions that str ongly supports the extension of these m e thods to other regulated source categories and elements.
7.2 Criteria for Candidate Method Applicability It is clear that when a candidate m e thod m eet s t h e r e

recomm ends that add i tio n al te st da ta be subm itted to extend the applicability of the ca ndidate m e thod to other source categories. T h is reco m m e n d a t i o n , h o w e v e r , d o e s n o t s p e c i f y c r that can be used to evaluate possible extensi on of a m e thod’s applicability when direct test data is not available. For the following disc ussion, it will be assum e d that the candidate m e thods will be applicab le to an un tested source catego r y if differences in em ission characteristics between s ources tested and candi date source em i s s i o n s a r e s u c h t h a t t h e y a unlikely to contribute significan tly to im precision and bias in m e a s u r e d m e t a l c o n c e n 7.3 Key Sampling and Analysis Features
B o t h t h e X F M a n d X a c t

- I A P d r a w a r e p r e s e through an u p stream PTFE filter th at rem oves PM from a gas stream and then th roug h a downstream reactive filter that traps vapor phase m e t a l s
. T h e X a c t

- I A P , o n t h e o t h e r h uses a single reactive filter to trap both the PM and vapor phase m e tals. Both m e thods m easure the m a ss of each m e tal dep o sited on th e filter(s) us ing XRF analysis proc edu r es based on EPA’s IO Compendium Method 3.3 14 . T h e concentration of m e t a l i n s t a c k g a s is ca lcula t ed by dividing the m a ss of m e tal in the f ilter ( s) d e p o sit ( M ) by the volum e of s t a gas (V) tha tpassed th rou gh the f ilter( s ). That is;

V M C = E q u a t i o n 26
Key sam p l i n g a n d a n a l y of the m e tal m a ss and volum e determinations . Consequently, a m e thod wi ll likely be

m e s i s f e a tu r e s a r e t h u s t h o s e that con t ribu te to the qua ntitativ e acc uracy applicable to a particular source em issions categ o ry if the dif f erences in s t ack gas characteristics are su ch that they do not signifi cantly con t rib u te to inaccu racies in vo l u and m a ss measurem ents.

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Page 57 of 75 a s o rr o s i v e s p e c i e s s u c h a s a c i d s , S O 2 , etc. prior to volum e determ ination. This dilution and extensive c onditioning of the stack gas prior to volume

t h e

n

cienc y A g , a n d c o n t r o l s u c h s a m i n e, dew point, and PM concentra tion in their optim al range. As such, the m e thod’s sensitiv ity to s p ecific s t ack gas characteris tics is s i gnificantly reduced

t i o n

k

P M a r e e l l e s t ab l i s h e d a n d g e n e r a l l y a c c epted to be greater than 99% are not expected to be

l

Characterization of em issions depends on such factors as source type (combustion, process, c t e d or fugitive) and type of controls (filtration, electrostatic precipitato rs, scrubbers, absorbers, reactive, etc.). Ho wever, from the m e thod

n t o In the case o f volum e determ ination, both m e thods dilute, coo l , filter, and dry the s t ack g a s well as denude the gas of c determ inatio n m a kes it r e latively ins e nsitive to d i fferences in stack gas ch aracteristics. Thus, if differences in stack gas ch aracteris tics are to significantl y i m p a c t t h e a c c u r a c y o f m easured aerosol concentration, it must be through the m e tal m a ss determ ination. Accurate d e term ination o f m e tal m a ss depe nds on two key factors, which m a y d e p e n d o stack gas ch aracteristics:

• XRF analytical de term ination of m e tal m a ss in th e f ilte r depo sit

• Filte r trapping ef f i

a i n i t i s i m p o r t a n t t o n o t e t h at both m e thods use dilution to m a i n t a i n

p l g c o n d i t i o n s a s t e m p e r a tu r even for these two factors. For example, when applying these m e thods, the applications engineer is directed to adjust non-critical param e ters within sp ecified lim its such as dilution ratio and sampling tim e to optim ize the m e thod for a particular appl ication. Furtherm ore, since there is no direct interaction between st ack gas and the analysis, the XRF determ i n a of m e tal m a ss in the filter deposit is only indi rectly dependent on the ch ar acte ris tics of the stack gas through how the stack gas impacts the ch aracteristics of the d e p o s i t o n t h e f i l t e r
. Other than the analy t e metals of inter e st, th e only species d e po sited on the f ilter are no nanalyte PM species, the total m a ss of which is controlled through the m e t h o d ap p l i c a t i o n b y selecting optim a l sa m p ling tim es and dilution rati os. None of the m a jor com p o n e n t s o f s t a c gas are trapped on the filters and cannot th erefore interfere with the XRF analysis.
For this reas on, the only factor that might be s e ns itive to stack gas charact eristics is th e filter trapp i ng ef f i ciency f o r P M and vapor phase m e tals. Filte r trap ping ef f i cien cies f o r 23, 31 w dependent o n dif f e rence s in sta c k ga s chara c te ris tics. As suc h, f ilter trap ping ef f i cien cy f o r vapor phase m e tals is the key factor that m i ght be im p a c t e d b y s t a c k g a s c h a r a c t e r i s t i c s
. T h e prim ary focus of the next two sections is on the potential dependence of vapor phase m e t a trapping efficiency on flue gas conditions and the available data showing the range within which the method has demonstrated acceptable q u antitation.
7.4 Key Emission Characteristics
fuel type, etc.), type of em i s s i o n s ( d u applic abilityevalua tion perspec tiv e, the characteristics of emi ssions that are m o st relevant are those defined in term s of their physic al (primarily tem p erature) and chem ical (com positio n) characteristics. Em iss i ons are g e n e rally com p osed of varying am o u n t s o f a i r (N 2 , O 2 ), combustion products (NO x , SO x , CO 2 , CO, H 2 O, et c.), contributions from c o n t r o l s (Na, Ca, H 2 O, NH 3 , etc.) and various process species, a n d c a n b e f u r t h e r d i v i d e d i catego r ies such as PM, reactive and non -reactiv e gases, acid vapors, etc.

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Page 58 of 75 h e n i s t s , h o w e v e r , f o r r s a n d t e ,

t

c e

, a n d

c o n d u c t e d

T i pp e, IN Board m an , O R M i d w est T o o e l e , UT As discussed above, the filters used by th e XFM and Xact-IAP have a high PM m e tals trapp i ng efficiency regardless of the stack gas ph ysical and chem i c a l c h a r a c t e r i s t i c s w sam p ling within th e con d itions spec if ied by thei r SOPs. So me potential e x the vapor phase collection efficiency to be im pacted by the stack gas physical param e t e chem ical composition. F o r both the XFM and Xact -IAP, the sam p ling temperature, f l o w r a and pressures are controlled by the operat or within the bounds of the SOP and are independent of the source type. Thus, the key ch aracteristics of e m issions that m i ght impact the re active f ilter ’ s trapp i ng ef f i cienc y are th e sa mpling inte r f e rences cau sed by rea c tive gases such as NO x , SO x , NH 3 , Cl 2 , HCl, HNO 3 , a nd H 2 SO 4 . A l t h o u g h t h i s l i s t i s n o com p lete, it does represent the m o re abundant and m o re reactive species likely to be present at varying concentrations in m o st stacks of regulatory interest. O x y g e n w a s n o t l i s t e d , s i n it is expected to be present in m o st em issions at am b i e n t c o n c e n t r a t i o n s ( 2 1 % ) o r l e s s laboratory tests in Phase I dem onstrated high trapping efficien cy at th e hig h est likely O 2 concentratio n. Potentially inte rf ering reac tive ga s e s are lis ted below in Table 23 along with m easured stack gas concentrations during s upplem ental testing discussed below and in Appendix L. Although this list is incom p le te, the concentrations and con d itions are representative of these sources and cover a broad range of co ncentration s and tem p eratures.
Table 23. List of stack conditi ons for w h i c h X a c t
- I A P a n d X F M t e s t s h a v e b e e n Phase II CF PP- CES C F PP- EP A H W C - T E A D Sp ecies CO , dr y p p m 14 < 10 NA 10 O 2 , dr y % 1 1 4 .5 12- 15 14-15 CO 2 , dry % 6 12.5 4

- 8 5 NO x , dry pp m 110 200 70 12 00 SO 2 , dry pp m N D 225 20- 35 10 HCl ( e q u iv.) , dr y p p m 2 N A N A 5 0 H 2 O % 9 10 15- 20% 5 PM @ 7% O 2 m g /ds c m 4 2 7 N A 1 0 T e m p °F 170 300 160 45 0 NA: No t Available C F P P

- CES: CES s p ons or ed c o lle c t ion ef f i c i enc y tes t at PG E CF PP N D : N o t D e tec t ed C F PP

- EPA: EPA s p ons or ed tes t of H g m onitor s HW C- T EAD: US Arm y s pons or ed tes t s at dem ili ter i z a tion HW C
7.5 Filter Trapp ing Efficien cy for Vapor Phase Meta ls The Clean Air Act lis ts 1 1 m e tals as air toxi cs: S b, As, Be, Cd, Cr, Co, Pb, Mn, Hg, Ni and

. t e l y i n t h e v ap o r p h a s e a t t h e operating temperature of the Xact-IAP and XF M (180°F). For this reason, Hg is the m o st

t e s t s Se 10 O f thes e m e tals, Hg is the on ly one that is predom i n a challenging to trap by filtration and most sensitive indicator of vapor phase m e tal trapping efficiency. Over the pas t several years, three se r i e s o f H g t r ap p i n g a n d r e l a t i v e a c c u r a c y have been conducted in addition to P h ase I and II tests described in the first part of this report. W h ereas Phase II tests dem o nstrated high Hg trapping effici e n c i e s u n d e r c o n d i t i o n s more repres entative of em issi ons from m odern hazardous waste in cinerators, thes e ad dition a l tests focused on em issions from coal-fired boilers. The supplem ental tests were m o re challenging in part because of their lower Hg concentration s (<10 μg/dscm ) b u t a l s o b e c a u s e of the presence of higher concentr ations (Table 23) of potentially interfering species s u ch as

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Page 59 of 75 b y

d

coal-fired power plant in B o ardm an, OR to e v s u n d e r a variety of sampling cond itions. For these tes t s, m e rcury was injec t ed into e ither laboratory air or stack effluent and the ry

i n t o t h e

an E P A sponsored evaluation of m e rcury m e e r p l a n t 5

. T h e s e t e s t s , c o n d u c t e d i n J u l y 2003, com p ared sim u ltaneous XFM and Ontario- Hydro Reference Method (OH) m e asured b a s e d NO x , SO 2 , SO 3 , NH 3 , PM, etc. The first series of te s t s d i s c u s s e d b e l o w w e r e s p o n s o r e d CES and we re conducted both in the laboratory and at a coal-fired utility boiler to def i ne the concentratio n range of applicab ility for the reac tive filters. T h e second and third s e ries of tests were sponsored by the EPA and the army, and focused on relative accuracy of the m easurem ents at coal-fired boiler emissions. In the follo wing summaries, an accep table relative accu racy when com p ared to an EPA au thorized reference m e thod will be taken to im ply an acceptable vapo r phase trap ping efficien cy. The supplem ental tests summ a r i z e below are discussed in m o re detail in Appe ndix L and supporting reports are provided in Appendix M. 7.5.1 CES Sponsored Trappin g Efficiency Tests A series of tests were conducted at CES and a a l u a t e t h e H g t r ap p i n g e f f i c i e n c y o f r e a c t i v e f i l t e r trapp i ng ef f i ciency ev alu a ted with th e XFM using two reac tive f ilte rs in serie s . The m e r c u trapp i ng efficiency was determ ined by com p ari ng the Hg trapped on the upstream f

ilter with the total m e rcury collected on both filters. Mer c u r ic ch lor i de laborato r y te sts in the tem p erature range between 100 and 212°F exhibited capture efficiencies g r e a t e r t h a n 9 9 % f o r concentrations ranging in excess of 800 μ g/dscm with sampling tim e s up to one hour. Sim ilar tests were conducted at the coal-fired power plant using elem enta l H g s p i k e d stack gas. In this case, the elem ental Hg trapping efficiency was greater than 99% for concentrations ranging up to 300 μg/dscm

. 7.5.2 EPA Sponsored Relative Accuracy Tests CES tested the XFM filter appro ach during a s u r e m ent m e thods at a Midwest coal-fired p o w

m e rcury concentrations between 1 and 6 μ g / d s c m
. T h e a c c u r a c y o f t h e r e a c t i v e f i l t e r m e thods at low concentrations was dem onstrated using an in-stack version of the XFM. A total of 12 two-hour OH runs were conducted. F o r each OH run, two simultaneou s 50 m i nute, in-stack XFM samples were collected by CES. For these tes t s, the X F M a n d t h e O H results were in good agreem ent with a relative ac c u r a c y o f 1 1 % f o r t h e n i n e v a l i d r u n s , w e l l within the 20% criteria f o r conditional m e t hods specified by EPA’s proposed Perform a nce Specificatio n 12 32 . Thre e of the 12 OH test runs were om itted f r om comparison by the EPA contractors. Two were om itted because of poor OH replication (>40% difference) an d one was om itted due to a plant upset. Th e rem a ini ng nine runs were used for com p arison, the results of which are plotted in Figure 19. Th e high correlation of these results and low rela tive accu racy dem onstra t es th e effectiv ene ss o f the reac tiv e filte r approach for trap p i n g and quantifying Hg concentrations between 1 and 6 μ g/dscm.

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Me rc u r y

y = 0. 908x + 0. 152 R 2 = 0. 962
0 1 2 3 4 5 6

012 3456 O H C o n c . ( μ g/ ds c m )XFMConc.(μg/dscm) n= 9
R A = 11%

Figure 19. Comparison of Hg con centrations determined by XFM and Ontario Hydro reference method at a coal-fired po w er plant. 7.5.3 US Army Sponsored Relative Accuracy Tests The U.S. Ar my sponsored a series of tests in January 2005 to evaluate a mercury-optim ized Xact at a co al-fired power plan t 33 . F o r these tests, m e rcury and ar senic were spiked into stack gas followed by sim u ltaneous Hg and As m easurem ents using the Xact and Reference Method 29. The results from these tests dem ons trated relative accuracies of 17% for these two elem ents, m eeting the proposed 20% criter ia proposed for Perform a nce Specification 10. 7.5.4 Summary of Trapping Efficiency Sens itivity to Reactive Stack Gases Unlike the p hysica l f iltra tion m echanism used to collect particulate m e tals, vapor phase m e tals react with the ch e m ically tre a ted filte r a nd bind to th e filter subs tra t e. Som e stac k gas constituents could potentially in terfere with this process. Ho wever, the more abundant stack gas species s u ch as N 2 , O 2 , CO 2 , CO, and vapor phase H 2 O are relativ ely inert, are not trapped on the reactive f ilter, a nd tes tresu lts indicate that th ey do not influence the filter trapp i ng efficiency. Oxidants with in the gas s t ream such as Cl 2 have been shown to improve the vapor ph ase collectio n efficiency for Hg. Other m i nor stack gas com p onents such as NO x , SO x , a nd NH 3 , have the potential to inte rf er e withvapor phase Hg trapping efficiency. However, this poten tia l to inte rf ere h a s not b een observed in the exte nsiv e tes ting th at has been conducted to date. For ex am ple, the possibility of NH 3 interferen ce was evaluated during EPA’s test of m e rcury m easurem ent appr oaches at a M i dwest coal-fired power plant with state-of -the-art ammonia injecti on and selective catal ytic reduction NO x control equipm ent 34 . Despite the use of a mmonia, the XF M reactive f ilter dem onstrated an 11 % relative accu racy when com p ared to the Ontari o - Hydro Hg reference m e thod concentrations, which ranged from 1 to 6 μ g/dscm . Sim ilarly, minor reactive com ponents such as NO x , and SO x have the potential to im pact vapor phase co llection efficiency. However, there is no indication th at these species affected the Hg tra pping efficiency at the c onc entra tions listed in Table 22. Indeed, the 99+% trapping efficiencyfor elem ental Hg at the B o ardm an site was com p leted with m easured NO x concentrations of 200 PPM and SO x concentrations of about 225 PPM. In addition, there is no indication th at high acidic concentrations affect the trapp i ng efficiency s i nce nitric acid concentra tions during Phase I and II testing was greater

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 60 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s than 50 PPM. The tests conducted to date a nd the range of key test param e ters are summarized below in Table 24.

Table 24. List of test co nditi ons an d references used to ev aluate meth od applicability.

Te s t S u m m a r y Te s t Concentr a t ion Ra n g e Par t ic u l a t e Me t a ls 3- 22 00 μ g / d s c m 1 , 2 El e m e n t a l Merc ury 1

- 3 14 μ g /dsc m 3 , 4 O x i d iz e d Merc u r y 1

- 8 80 μ g /dsc m 3 , 5 Holdin g Ti m e X F M: Pa r t ic u l at e F ilt er 12 Mo nt h s 6 , 7 X F M: Vapor Phas e F i lter 24 Mo nt h s a 8 Xac t 1 2 Mon t hs 6, 7, 8, 9 Stac k T y pe & Conditions Fi lt ers a c c ept ab le f o r W e t Stack s 3, 10 , 1 1 Fi lt ers a c c ept ab le f o r D r y St ac k s 1, 2, 4, 9 HW C F i l t e rs a c c ept ab le f o r H W C a p p l i c a t i o n s 1, 2, 9, 1 1 CFPP Fi lt ers a c c ept ab le f o r C F P P a ppl i c at io ns 3 , 4 , 10 Stac k T e mpera t u r e 4 50° F 1 , 2 Filter T e mpe r ature XF M P a rti c ul at e Fi l t er 4 00° F 1 2 X F M Va po r Pha s e F i lt er 18 5 ° F 4 , 5 X a c t Pa r t ic u l at e / Va po r Pha s e F i lt er 18 5 ° F Sa mplin g Ti m e XF M 6 0 m i n 4 , 5 Xact 3 0 m i n 1 0 Sa mplin g Flow Rate XF M 4 .5 l p m / c m 2 4 , 12 Xa ct 2

. 4 l p m / cm 2 1 2 Fiel d Blank Det

. Li m i ts l e s s tha n 2 μg / d scm b 11 a) Correc t io n f a c t o r of 0.5 % /m on th r e qu ire d a f te r s i x m o nt hs

. b ) O n e - s i g m a li m i t s ba s e d up on an al y s is of 38 9 9 f ilt er s m e a s ur em e n t s a t L illy ' s T 1 4 9 I n c i n e r a t o r

1 H W C a t T EAD pr o d u c t io n f u r n a c e ( S e c tion 2. 3)

. 2 H W C at T EAD re s earc h f u r n ac e (Sec t i o n 2

. 3 )

. 3 E P A te s t a t Mi dw es t C F P P (Se c ti on 2. 3). 4 C ES T e s t at O r ego n CFPP (Sec t i o n 2.3 )

. 5 C ES La bora t ory T e s t s (Sec t i o n 2

. 3 )

. 6 R ee v a l u a t i o n of Ph as e I Fi lt ers (Se c ti on 2.3 )

. 7 EP A P M 2. 5 Sp ec i a t i o n Progra m 7 ; Reev a l uat io n o f P h a s e I Fil t e r s ( S ec ti o n 2

. 3). 8 C ES La bora t ory Ev a l u a ti o n o f XFM Fi l t ers (Se c ti on 2. 3). 9 C ES Rean al y s i s of X a c t Fi lt er T a pe f r om T E A D tes t s (Sec t i o n 2

. 3 )

. 1 0 Xac t T e s t a t IA AP C F P P (Se c ti on 2.3 )

. 1 1 Ev a l uat io n o f B l a n k Fil t e r s at Li l l y ' s T 1 4 9 I n c i ne r a tor (Se c ti on 2. 3). 12 Ma nu f a c t ur er s Sp ec if ic a t ion s 1 3 Ph as e II T e s t s at Li ll y ' s T 1 4 9 In c i ne r a tor Pa r a m e t e r

Mois tur e

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 61 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s 7.6 Applicable Concentration Range The applicable concentration range for these re active filter based m e thods was extended to over 2000 μg/dscm during Xact and Reference Me thod 29 relative accuracy tests conducted in 2002 at an Ar m y hazardous waste test incinerator 34 . Twelve Reference Method 29 test runs were conducted while the stack gas Pb c oncentrations ranged from a low of about 10 μg/dscm to over 2200 μg/dscm

. The results from these twelve tests are com p ared to the corresponding Xact results in F i gure 20. These results show a high degree of linearity over this broad range of concentrations and a high re lative accuracy of 4% when com p ared to the Method 29 results. If these re sults are com b ined with thos e in the preceding subsection where the H g results were in good agreem ent with the reference m e thod down to alm o st 1 μg/dscm , it is clear that the m e thod is quantitat ive over at least three or ders of m a gnitude and at concentrations greater than 2200 μg/dscm

.

Le ad

y = 1

. 05 8 5 x + 1. 2 181 R 2 = 0. 999 7 0 50 0 1, 0 0 0 1, 5 0 0 2, 0 0 0 2, 5 0 0

0 500 1 , 00 0 1 , 500 2, 000 2 , 50 0 M e t hod 2 9 C o n c . ( μ g/ds c m )XactConc. (μg/dscm) n= 12
RA = 4 %

Figure 20 Plot of Xact-IAP concentrat ion versus Reference Method 29 measured concentrations show ing excellent agreemen t over tw o orders of mag n itude and at concentrations in excess of 2,000 μg/dscm. 7.7 Deposit Stability The Xact-IA P uses a reel-to-reel tape system to collec tstack g a s m e tal sa mples, whic h are then transported to a position for XRF analysis. Af ter analys is, the tape is drawn over a take up spool where th e expo sed filter deposits com e into con t act with following tape as it wraps over the previously exposed tape. S o m e potential exists f o r transf er of m e tals f r om their origin al dep o sit to the ta pe c overing the deposit. If this tran sf er were s i gn if icant, it wo uld reduce the p o tential to p o st-test v a lidate Xact-I AP results w ith independent analysis of the deposits. A s such, post test analyses were c onducted on 72 deposits coll ected during relative accuracy tests conducted in May 200 2 at a US Army hazardo us waste pro duction incinerato r at the Tooele Arm y Depot (TEAD) in Tooele, UT 34 . During these tests, the Xact m o nitored em issions in an instrum e nt shed about 40 f eet f r o m the incine rator sta c k while EPA Reference Method 29 sam p les were collected at the stack. T w elve Method 29 test runs were conducted w ith concentrations varying from 5 to 300 μ g/dscm. There was very good agreem ent with the reference m e thod as illust rated in Figure 21. The relative accuracy was 4% and the results exhibite d a high degree of linearity.

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 62 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s Following these tests, the exposed filter tape was st ored at room tem p erature at CES. Two months after the field tests were com p leted, the tape was rem oved from the spool exposing the previously collected deposits. T h ese deposits were cut from the tape and analyzed with CES’ laboratory XRF analyzer. These laborat o r y results are com p ared to the original concentrations reported by the Xact in Figure 22. Clearly, there is a high degree of agreem ent between the o r igin al Xact Pb result s an d the labo ratory re sults. The slope and correlation suggests that there wa s not a significant transfer of Pb from the deposit to the covering tape at the level of a few per cent.
Le a d

y = 1.0 9 x - 9. 60 R 2 = 0

. 9 8
0 20 40 60 80 10 0 12 0 14 0 16 0 18 0

0 5 0 1 00 15 0 2 00 M e t h o d 29 C o n c . ( μ g / d scm )XactConc.(μg/dscm) n = 1 2

Figure 21. Plot of Pb concentratio ns det ermined by Reference Metho d 29 and the Xact.

Lead

y

= 0. 9727 x + 3. 4 259 R 2 = 0. 9685

0 20 40 60 80 100 120 140 160 180

0 5 0 100 1 5 0 200 X act C o nc. ( μ g / m 3 ) ; M ay, 20 02Lab Conc.(μg/m3)July, 2002 n = 7 2

Figure 22: Comparison of resul ts from laboratory XRF anal ysis in July, 2002 w i th Xact field test results from May 2002 relative accu racy tests at a haz a rdous w a ste incinerator
7.8 Moisture Over the last three y ears, the Xact-IA P and XFM have been evaluated on both wet and dry stacks (Table 25) using Method 29, Ontario-Hydro and the Q AG reference aerosols. In all

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 63 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s cases, th e Xact-IAP and XFM showed good relati ve accuracy and trapp i ng efficiencies. For this reason, it is believed that the candidate m easurem ent m e thods are valid for both wet and dry stacks as long as the probe and filter tem p erature rem a in above the water vapor dew point, which are controlled prim arily with dilution.
Table 25: Recent tests o f Xact and XFM on w e t and dry stacks.

Da te Test Lo catio n Inc. Ty pe Air Po llutio n Co ntr o l Technol o gy Wet or Dry Stack Elements An al yz ed Results

Mar c h 2 005 Eli Lilly Lafayette, IN HW C Scru bb er W e t As, C r , C d , Hg , P b Xact and XFM within 15 % of Q A G p r ed ictedfor As, Cr, Cd, Hg, P b Jan. 2 005 IA AP Am es, IA C F P P S c r ub b e r W e t A s , H g Xact RA of 17% vs

. M 29 f o r As , H g Sept. 2 003 TEAD Tooele, UT HW C High Tem p
. Bag hou se Dry P b Xact RA of 4% vs

. M 29 f o r Pb May 2 003 M i d w e s t C F P P Am m oni a in

j ection , SCR,

b a gho use Dry H g XFM R A of 1 1 % vs
. O H fo r Hg
Au g 2 002 Boardm an, OR C F P P S c r ub b e r W e t H g o Trapping e ffici ency of 99 % f o r H g o

7.9 Holding Times Tests were also conducted to evalu a te the hol d i ng tim es for the XFM and Xact-IAP filters. These tes t s included both the XFM PTFE filter and the reactive filter. D u ring th e Decem ber 2004 Phase I tes t s, th e PTFE filter h a d collect ed particulate As, C d, Cr, Hg, and Pb at concentrations ranging from 20 μ g/dscm to 125 μ g/dscm . In order to d e te r m ine PTFE f ilter holding tim e s, CES reanalyzed filters from seve n of these tests (Runs 1-4 and 21-24) in April 2005. During the five months between the initia l and second XRF analysis, the filters were stored at roo m tem p erature in p l astic petrie dishes. Both analyses were conducted using XRF following the IO Com p e ndium Method 3.3 14 . Overall, the av erage m e tal concentratio ns m easured in April 2005 were within one percen t of the concentrations determ ined five months earlier. All m easurem ents were within 4% of their original concentration, with no significant bias. The good replication of the m e ta l m a ss dem o nstra t es the ability of the PTFE f ilter s to r e ta in m e tal concentr ation s over a f i ve month perio d. Reactive filter tests were conducted to determ in e retention efficiencies and estim ated holding tim es for vapor phase metals using Hg as an ind i cato r species. These tes t s are b a sed on filters expos ed to both elem ental m e rcury and m e rcuric chlo ride vapors du ring tests conducted in June and August 2002 a nd filters from coal-fired power plant flue gas tests. All filters were kept at room tem p erature a nd analyzed using IO Com p endium Method 3.3 14

. These filters were rean alyzed periodically ov er th e past two years and were found to have lost on average about 10% of the original m e rcury over this period. This finding was

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 64 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s independent of laboratory or field applicati on, or oxidation state of Hg trapped. A linear model was developed which assum e s the m e rcury lo ss from the reactive filter to be con s tant over tim e . This m odel showed that, when usi ng a correction factor th at assum e s a loss of about 0.5% per m onth, the m e rcury concentrat ions m easured after two years were, on average, within 10% of the original m e rcur y concentrations. The good agreem ent for all of these tests s upports th e use of a correction factor of 0.5% per m onth for filters that have been archived for more than six m onths. This woul d allow the hold i ng tim e to e x tend to a tleast two years. 7.10 Applicable Elements The XRF analysis d e te r m ination of m e tals in the f ilter d e posit is bas e d on EPA IO Com p endium Method 3.3, which is generally app licable to elem ents with atom ic numbers ranging from about 13 (Al) through 92 (U). This range of elem ental app licability is expected to apply to the XFM PTFE f ilter but not to th e re activ e f ilter. In the c a se of the reac tive f ilter, the lo west atom ic num b er ele m ent quantif iable with XRF analysis is Cr (24) b e cause of

signif i can t im purities in the f ilter m a trix. The elem ents of prim ary regulatory interest ar e those the Clean Air Act Am endm ent s class i fy as Air Toxics: i.e. Antimony (Sb), Arsenic (A s), Beryllium ( B e), Cadm ium (Cd), Chrom i um (Cr), Cobalt (Co), Lead (Pb), Manganese (Mn) , Mercury (Hg), Nickel (Ni), and Selenium (Se). These eleven elements have b e en sort ed by volatility in the Maxim u m Achievable Control Technology (MACT) rules 17 as f o llows:

• Non-enum er ated m e tal com pounds (N): Sb, Co, Mn, Ni, Se; equated to particulate m a tter in the MACT

• Low volatile m e tal com p ounds (L): As, Be, Cr

• Se m i -volatile m e tal compounds (S): Pb, Cd

• High volatile m e tals (V): Hg The m e tals tested in Pha s e I and I I re presented pa rticula t e m a tter as we ll a s all of the m e tals in the three volatility ca tegories except the low volatility elem en t Be. The other elem ents not tested are no n-enum erated m e tals, wh ich the EPA has equated to particulate m a tter in the MACT rules. Although these eleven elem ents re present the prim ary focus of this discussion, it is im portant to note that these filter based m e thods are expected to be applicable to most of the elem ents listed in EP A IO Com p endium Methods 3.3 14 and Be by IO Com p endium Method 3.4 35

. 7.11 Other Related Tests 7.11.1 Sample Collection T i mes The theore tical sam p ling tim e f o r the XFM and Xact- I AP is pr im arily lim ited by f ilte r loading withPM since X R F correctio n factor s m a y be required for high particulate deposit densities. H o wever, the f ilter loadin g can be con t rolled in so urces with h i gh particu l a t e lev e ls by adjusting the sam p ling tim es and dilution rati os up to 4:1. For this reason, it is believed

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 65 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s that, these filter-based methods can sam p le fo r pe riods up to f our tim es greater than has currently been dem onstrated; i.e. four hours for the XFM and two hours for the Xact-IAP. 7.11.2 Xact Blank Concentrations The Lilly X act, was ins t alled on the T149 h azard ous waste in cinerator in May 2004 and operated throughout the summer of 2004. During this tim e , the Xact com p leted about 4000 runs while the stack was not burning hazardous waste. These runs were treated as field blanks and were used to statis tica lly determ ine Xact- I AP dete ction lim its. These sta tis tica lly determ ined detection lim its were in good agreem ent with those calculated from the analysis of a few filters.
Table 26: Xact dete ctio n limits det ermined at Lilly’s T14 9 incinera to r

XF M 1 Xact 2 μ g/ds c m μ g / dscm CR 0.08 0.3 AS 0.08 0.1 CD 0.80 2.4 HG 0.14 0.3 PB 0.12 0.6 MN 0.08 0.2 CO 0.08 0.3 NI 0.06 0.3 SE 0.08 0.1 AG 0.60 4.2 SB 1.60 6.2 CU 0.08 0.5 F E 0.12 0.9 Z N 0.06 0.2 BR 0.20 0.4 SR 0.18 0.3 T L 0.14 0.3 DE T E CT ION LIM I T S Elem

1) 95% Confidence, Interfer ence free, 30 m i nute sam p le. 2) 95% of 3899 Xact blank m eas urem ents at T149 Incinerator

7.12 Applicable Source Categories As discusse d earlier, the f ilter

- based sam p ling a pproach has b een succe ssf ully tested in the laboratory and on two hazardous waste in cinerators as well as three coal-fired boilers. Each of these tests showed good rela tive accuracy and trapping effi ciencies. Source em issions can be divided into two cate gories : f ugitive and duc ted em issions. Fugitiv e s ources in clu d e em issions from processes such as field-bur ning, slag-pouring, em issions from buildings, dem o lition a c tiv ities, f o r e st f i res, etc. in addition to passive f u gitiv e em issions f r om sources such as win d -blown dus t and dust su spended by vehicular tra f f i c. These fugitiv e em issions are typ i ca llycharac ter i ze d by substan tia lly lowe r concentrations of po ssible reactive sp ecies

M e thod 301 E v al. : V1. 0 S e c t i o n 7

. 0 Page 66 of 75C o n c l u s i o n s a n d R e c o m m e n d a t i o n s 

### 8.0 Conclusions and Recommendations than the con centration s in the ducted em issions already successfully tested. As such, the XFM and Xact-IAP should be applicable, in gen e ral, to these fugitive em ission sources because the characteristics of their em issions are less challen g ing than th e ducted sou r ces already tested. Ducted sources, on the other hand, can have em i ssion characteristics sim i lar to those already tested, and in som e cases m a y exceed the valu es for som e param e ters that m a y be more challenging than thos e already tested. As di scuss e d ear lie r, th e f ilte r-bas e d approach has shown consistent su ccess over the p a st few y ears while sam p ling at two hazardous waste incinerators and three co al-fired boilers with a w i de range of controls (wet scrubbers, ESPs, high tem p erature ceram ic baghouses, ammonia inj ection, selective catalyt ic reduction, lim e spray drye r absorber for SO 2 control, and a f a bric f ilter f o r pa rticula t e con t rol). In e a c h case the relative accuracy in com p arison to th e QAG, Ontario Hydro, and Method 29 was better than the EP A required 2 0 % for condition a l m e thod consideration. In g e nera l, the filter-based approaches have been accurate regardless of source category, em ission control technology used, m o isture content and stack chem istr y. As such, the Xact-IAP and XFM m e thods should be applicable to a wi de range of source categories including incinerators, boilers, kilns, sm elters, plating operations, foundrie s, m i neral processing and other industrial processes using a wide range of pollution control technologies.

The results from Phase I and II tests and the pr eceding discussion, as we ll as results from previous tests, support the following conclusions. 1. The QAG ca ndidate reference aerosol gene rator met all of the required validation criteria and should be approved as a NIST-t raceable reference aerosol generator for initial certif ication and c ontinuing qu ality assu ran ce audits f o r

m u lti-m e tal sam p ling and analysis m e thods. 2. The XFM candidate con d ition a l m e thod for m easuring m e tal concentrations in em issions from stationary sources m e t al l of the required validation criteria and should be approved for initial certification and c ontinuing quality assurance audits of multi-m e tals CEMS. 3. The Xact-IA P candidate conditional m e thod for m easuring m e tal concentrations in em issions from stationary sources m e t al l of the required validation criteria and should be approved for use at incinerators for initial certification and continuing quality assu r a nce audits of m u lti-m e tals CEMS. 4. The QAG ca ndidate reference aerosol generato r is independent of its application and should be approved as a genera lly applicable reference aero sol generator f o r research, m e thod certification, and audit validation. 5. The XFM and Xact-IAP candidate conditio n a l methods have dem onstrated their applicability to a wide range of source types, controls and stack conditions; and because of their use of d ilution techn i ques a nd th e resulting insensitivity to stack gas characteristics; these m e thods should be approved as conditional reference m e thods

M e thod 301 E v al. : V1. 0 S e c t i o n 8

. 0 Page 67 of 75for use in regulatory applications where stack gas m e tal em ission m easurem ents for f ugitive or stationa ry sou r ces a r e r e qu ired.


### 9.0 Glossary Accuracy: The closeness of agreem ent between a m easured value and th e true v a lue. Accuracy involves a combination of random error com pone nts and a system atic bias com ponent. Aerosol: A dispersion of solid or liquid particles in gaseous m e dia. Analyte: Elem ent of interest in an analytical m easurem ent. Analytical NIST Trace a ble: Procedure in which NIST-t rac eability is ac hieved by calib rating the m easurem ent instru m e nt with NI ST standard reference m a terials (S RM) or standard s which are them selves traceable to NIST. To ensure continu i ng accuracy th e calibration of the m easuring instrum e nt shoul d be checked against the NIST standard reference m a terials or N I ST traceable m a terials o n a regular b a sis. Approved alternative method: A procedure that is an a pproved alternative to a m e thod required by 40 CFR Parts 60, 61 and 63 as desc ribed by the General Provisions of the corresponding Parts. As such, it m a y be used by sources for determ ining com p liance with the requirem e nts of these Parts per their specified applicability provision s without further EPA approval. Aspiration: The process by which a liquid is drawn from a r e servoir through a narrow tube by creating a vacuum above the tube with fast moving air. Atomiz ation: The process of converting a liqui d into sm all suspended droplets. Attenuation : Reduction of a m plitude or change in wave for m due to energy dissipation or distan ce. Audit: A methodical exam ination and review. Bias: The d i fference between a m easured m ean and the true value. Bias represents system atic d i fference. Blank: A sample known to have a param e tric value of zero. Calibration Drift (CD): The difference in m easured outpu t readings from a calibrated reference v a lue after a stated period of operation during whic h no scheduled m a intenance, repair, or ad justm e nt too k place. Calibration : The process of com p aring a sam p ling or instrum e ntal re sponse with a known param e tric value for the purpose of obtaini ng a quantitative relationship between the response and the parametric valu e. This relationship can th en be used to determ ine the param e tric value for an unknown sa mple. Candidate method: T h e sam p ling and analytical proce dure selected for validation by the m e thod described herein. Certif icat io n: To attest to being true or as re presented or as m eeting a standard.

M e thod 301 E v al. : V1. 0 Section 9.0 Glossary Page 68 of 75Compendium method: A collection of approved EPA m e th ods f o r the de term ination of inorganic (IO) or organic (TO) compounds in ambient air. Conditional test metho d : Methods that have been evaluated by the EPA and m a y be applicable to one or m o re categories of stationary sources. T h ese m e thod’s QA/QC procedures are requ ired as a condition of appli cability and m u st be approv ed as alternatives before a source m a y use them to m e e t Federal requirem ents under 40 CFR Parts 60, 61, and 63. They m a y be used by State and local programs in conjunct ion with federally enforceable program s (e.g., Title V p e rm its, State Im ple m entation Plans (S IP)) prov ided they are su bject to an EPA Regional S I P approval process or permit veto opportunity and public notice and opportunity for comm ent. Correction factor: A quantity applied to a m easurem en t to adjust th e valu e of that m easurem ent to th e tru e value. Correlation coefficient: A num b er or function that in d i cates the degree of correlation between two sets of data or between two vari ables and that is e qual to their covariance divided by the product of their standard deviations. Detection Limit: The lowest concentration of a chem ical that can reliably be distinguished from a zero concentratio n. Drift : Percent change in a m ean va lue m easured over period of tim e. Elementa l ratios: The relationship in qua ntity, or m a ss between two or more elem ents trapped during a single sam p ling period. Emissions: The total of substances discharged in to the air from a stack, vent, or other discrete sou r ce. Error: The difference b e tween an o b served or calculated value and a true value; spe c ifically : variation in m easure m ents, calc ulations, or observations of a quantity due to unsystem a tic factors. Filte r : A porous m e dium for collecting particulate m a tter. Filte r rat i o: The relationship in quantity, or m a ss of an elem e n t trapped on two or m o re filters used in com b ination during a single s a m p ling period. Holding Time: The m a xim u m a m ount of tim e a sam p le m a y be stored before analysis. Impaction : A f o rcible c o llis ion of particle s of matte r with an object. Impactor: A device that em ploys the principle of i m paction. Intercept: The distance from the origin to a po in t where a lin e crosses a coordinate ax is. Interferent: A substance that causes system atic errors in the m easure m ent of another substance. Isokinetic sampling: E m issions sampling in which the lin ear velocity of the gas entering the sam p ling nozzle is equal to that of the undi sturbed gas stream at the sam p le point. Linearity :A check of the degree to which the candidate reference m e thod response is linear relative to a change in co ncentr ation of a reference aerosol a ch ange in concentration reported by a reference m e thod. .

M e thod 301 E v al. : V1. 0 Section 9.0 Glossary Page 69 of 75Low

- volatile metals (L VM) : Any m e tal that does not volat ilize readily (e.g., arsenic (As), beryllium (Be), and chrom i um (Cr)). Metal ratio : The relationship in quantity, or m a ss of two or more m e tals trapped on a filter or series of filters used in com b ination during a single sam p ling period. Method 29 : An EPA reference m e thod to determine the m e tals em issions from stationary sources it is contained in 40 CFR 60 Appendix A. Method 301 : An EPA protocol for the field valida tion of candidate pollutant m e asurem ent m e thods from various waste m e dia. Negative bias: Bias wh en the m easured resu lt is less than the “tru e” or reference v a lue. NIST: U. S. Departm e nt of Comm er ce, Nati onal Institute of Sta ndards and Technology, Gaithersburg, MD 20899 Non-destructive: Not causing destruction of m a teri al being investigated or treated Ontario Hydro Method A m e thod for determ ining the concentration of elem ental, oxidized, particle-bound and total mercury in flue gas generated from coa l -fired stationary sources. Outlier : Ex trem e m easurem ents that stand out from th e rest of the sam p l e and m a y be faulty. Partic le : A sm all discre te m a ss of solid or liqu i d m a tter. Particulate : Solids or liquids exis tin g in th e form of separate particles. Performance audit material: EPA-approved material of kn own com pos ition that can be used to sim u late an unknown sa m p le to test the candidate procedure. Performance Specifications: Perform a nce specifications are used for evaluating the acceptabilityof the CEMS at the tim e of or s oon after installation and whenever specified in the regu latio n s. Quality a ssurance p r o cedures in 4 0 CFR Part 60 Appendix F are used to evalua te the ef f ectivenes s of quality contro l (Q C) and qualityassuranc e ( QA) procedures and the quality of data produced by any CEMS that is used f o r de term ining co mpliance with the em ission standards on a continuous basis as specified in the app licable regulation. Pos i t i ve bi as : Bias when the m easured result is g r eater th an the “tru e” or reference v a lue. Practica l limit o f quantita t ion (PL Q ): The lowest level above which quantitative results m a y be obtained with an acceptable degree of co nfidence. The PLQ is defined as 10 tim e s the standard deviation, S o, at the blank level with an uncertainty of ±30% at the 99% confidence level. Precis i on: The degree of m u tual agreem ent be tween individual m easurem ents of a param e ter having the sam e value,. In this report it is defined as the percent relative standard deviation (P RSD) of a s e ries of m easurem ents over a r e la tiv e short tes t period in contrast to stability, which is a determ ined m easur em ent over an extended period of tim e
. Process NI ST Traceable: A parameter whose value is traceable to NIS T through a procedure, the steps of which are each NIST traceable 1

M e thod 301 E v al. : V1. 0 Section 9.0 Glossary Page 70 of 75Quality Ass u rance/Qua lity Contro l: A system of procedures, checks, audits, and corrective action s to en sure tha t a ll EPA researc h de sign and perform a nc e, environm ental m onitoring and sam p ling, and other technical and reporti ng activities are of th e highest achievable quality. Quantita tiv e Aerosol Generator (QAG) : An aerosol generator system that uses analytes of known concentrations in aqueous solution to create aerosol em i ssions of known m e tal concentratio ns. Quantita tiv e : Of, relating to, or inv o lving th e measurem ent of quantity o r am ount. QuanX ® :A Spectrace Instrum e nts energy-dispersi ve x-ray fluorescence spectrom eter. R : Correla tion coef f i cie n t, an ind i ca tor of how well the d a ta f

its a linear rela tionsh i p. R 2 1 : propo rtion of the total sum of squares that can be acco unted for by the linear regression of y on x 2 : a sta tis tic th at ind i cates the streng th of the rela tio nship betwe e n x and y. Reference a erosol: An aerosol that contains a known concentration or con centration s of analytes. Reporting time : The tim e interval f o r which the report is r e p r esentative. Representa tive sa mple : A portion of m a terial that is as nea r ly id entical in conten t a nd consistency as possible to that in th e larger body of m a terial being sam p led. Response time: The time interval from a step change in pollution concentration at the input to the continuous m onitoring system to the tim e at which 95 % of the corresponding f i nal value is reached as displayed on the con tinuous monitoring system s data recorder. Ruggedness test : A laboratory study to determ ine the se nsitivity of a m e thod to param e ters such as sam p le collection rate , interferent concentr ation, collecting m e dium tem p erature, and sam p le recovery tem p erature by cha nging several variables at a tim e. Sampling s y stem: The system whi c h extracts a sam p le of e ffluent gas from a source and and deliv ers it to po int w h ere co llection or m easurem ent of the analy t es in the source can occur. Secondary Particles (o r Secondary Aerosols) : Aerosols that form in a gaseous m a trix as a result of chem ical reactions. Semi-vo l atile meta ls : Lead (Pb), cadm i um (Cd). Slope: For a line described by the equation y = m x + b, m is the slope of the line. The slope expresses th e am ount of change that will occu r in y due to changes in x. Spectral Interferent: A n interfering elem ent or speci es that’s absorption or em ission characteristics overlap o r lie so clo s e to the an aly t es abso rptio n or em ission characteris tics that resolution becom e s im possible. SRM: Standard Reference Materials. Stability: T h e consistency in the m easurem ent of a constant value over an extended period of tim e.

M e thod 301 E v al. : V1. 0 Section 9.0 Glossary Page 71 of 75Standard: An item with a value f o r

a param e ter that has been established by authority, custom , or agreem ent to serve as a model or ru le in the m easurem ent of quantity or th e estab lishm ent of a practice or pro ced ure. Surrogate Data: Data from studies of test substance orsubs tances that are used to es tim ate the characteristics o r effects on ano t her substances. Thin film s t andard reference ma terial : A NIST traceable s t andard reference m a terial com p rised of either an elem ent(s) or com pound( s ) of a known and stable concentration. The thin film standards are u s ed to calib rate X-ray fluorescen ce in strum e nts. Traceable to NIST: A docum ented procedure by which a measured response is related to a standard with an accuracy defined by and cer tified by the National Institute of Standards Technology (NIST). Transport effic i ency : The percentage of a known concentrat ion of analyte or analytes that can be conv eyed to an analysis instrum e nt from their source. Uncertainty : A statistically defined value associat ed with a s i ngle m easurem ent or a value associated w ith a g r oup o f m easurements th at def i nes th e rang e and probability of addition a l m easure m ents falling within the defined range, and can include allowance for both system atic and random s ources of error. Unk n o w n: A sam p le subm itted f o r analys is whose elem ental concen tra tion is no t k nown. Upscale drift: The difference in an instrum e nt’s output readings from the established upscale reference v a lue after a stated period of operation during whic h no scheduled m a intenance, repair or ad justm e nt took place. Validation : The determ ination of the degree of validity of a m easuring device Verifiab le : Capable of being confirm e d for precision and accuracy. Verification : Confirm i ng the precis ion and accuracy of an ins t rum e nt. Volatile me tal : Any m e tal substance that evaporat es readily at low tem p erature (e.g., m e rcury). Xact : Cooper Environm ental Service’s X-ray fluo rescence based em issions m onitor capable of m easuring m e tals found in flue gas em issions. Xact-CEMS: Cooper Environm ental Service’s X-ray fluorescence based continuous m e tal em issions monitor. XACT-IAP : An instrum e ntal analyzer procedure utilizi ng Cooper Environm ental Service’s XACT to measure m e tal em issions from stationary sources. XFM: Cooper Environm ental Service’s X-ray based filter method to m easure m e tal em issions from stationary sources. Xact-IM : C ooper Environm ental Service’s X-ray fluorescence based continuous em issions monitor prim arily focused on the detecti on of mercury in flue gas em issions. XRF: X-ray fluorescence – An analytical techniqu e used to determ ine the concentration of an elem ent or elem ents.

M e thod 301 E v al. : V1. 0 S e c t i o n 1 0

. 0 R e f e r e n c e s Page 72 of 75Z ero Drift: The difference in an instrum e nt’s output read ings for zero inp u t after a stated period of operation during which no unscheduled m a intenance, repair or adjustm e nt took place.

R e f e r e n c e s 

### 10.0 Referen ces

1. EPA Test Method 301, Field Validation of Pollution Measurem ent Methods for Various Media, 40 CFR 56, 27370-27374. June 13, 1991. 2. EPA Test Method 29, Determ ination of Meta ls E m issions from Stationary Sources, 40 CFR 60, Revised July 1, 1996. 3. ASTM D6784-02. Standard Test Method for Elem ental, Oxidized, Particle-Bound and Total Mercury in Flue Gas Generate d from Coal-Fired Stationary Sources (Ontario Hydro Method), 2002. 4. Cooper, J.A, B.E. Johnsen, S.C. Fry, May 2003. Installation and Use of an X-ray Based Continuous Em issions Monitor for AED Treatability S t udy. Subm i tted to US Ar m y Equipm ent Directorate, Tooele Arm y Dep o t. Contra ct No. DAAA14-02-P0216. 5. Hosenfeld, J., Sept. 2003. Long-Term Field Evaluation of Mercury (Hg) C ontinuous Em ission Monitoring System s: Coal-Fired Po wer Plant Equipped W ith Dry Flue Gas Desulfurization/Fabric F iltration Em ission Contro lsPhase III (Field W o rk Perform e d May-July 2003). Final R e port for U.S. Environmental P r otection Agency. EPA Contract 68-D2-01-002 Work Assi gnm e nt 3-04. MRI Project No. 110130.3.004. 6. EPA. May 03, 2005. List of Designated Refe rence and Equivalent Methods (Am b ient Methods). F ound on EPA website at http://www.epa.gov/ttn/am tic/criteria.htm l

. 7. EPA. April 1994. Quality Assurance Handbook for Air Pollution Measurem ent System s. Volum e II: Ambient Air Specific Metho d s (Interim Edition ) . EPA/600/R94/038b. 8. Prieditis, H. IYR Ada m s on 2002. Compara tive P u lm onary Toxicity of Various Soluble Metals Found in Urban Part iculate Dust. Exp. Lung. Res 28: 563-576. 9. Monn C, Becker S. 1999. Cytotoxicity a nd induction of proinflamm atory cytokines from hum a n m onocytes exposed to fine (PM 2. 5 ) a nd coarse p a rticles (PM 10- 2. 5 ) in outdoor and indoor air. T oxico l Appl Pharm acol 155:245-252. 10. Clean Air Act Am end m ents of 1990 (CAAA), Pub.L. No. 10 4-549, 104 Stat. 2399 (1990). 11. EPA, 2005. Rules and Implem entations fo r Toxic Air Pollutants. Found at EPA’s Technology Transfer Network Air Toxics W e bsite. http://www.epa.gov/ttn/atw/eparules.htm l

.

M e thod 301 E v al. : V1. 0 S e c t i o n 1 0

. 0 Page 73 of 7512. EPA 450/4-92-013 Vol. 1 Decem ber 9, 1991. Evaluation of Two Methods for the Measurem ent of Mercury Em issions in Exhaust Gases from a Municipal Waste Com bustor. 13. Rigo, H.G., A.J. Chandler. Quantiation Li m its for Reference Methods 23, 26, and 29. J. Air & W a ste Manage. Assoc. 49:399-411. 14. EPA Compe ndium of M e thods for the De term ination of Inorganic Com p ounds in Am bient Air. June, 1999. Com p endium Method IO-3.3 Determ ination of Metals in Am bient Particulate Matter Using X- Ray Fluorescence (XRF) Spectroscopy. EPA/625/R-96/010a. 15. Jayanty, RKM. 2002. PM2.5 Che m ical Speciation Nationwide Network and its Challenges. Sym posium on Air Quality Measurem ent Methods and Technology – 2002. San Francisco, CA. 16. May K.R. (1973) The Collison Nebu lizer. De s c rip tion, Perform a nce & Application J. of Aerosol Science, Vol. 4, #3, p. 235 17. US EPA. NESHAPS Standards for Air Po llutan t s for Hazardous W a ste Com bustors Final Rule. FR67 No. 31 pp. 6967-6996. February 14, 2002. 18. Eli Lilly and Com p any T 149 Liquids and Solid Waste Incinerator. Tippe, IN. 19. US EPA PS- 11. Performance Specification 11 – Specifications and Test Procedures for Particulate Matter Continuous Emissi ons Monitoring System s at Stationary Sources. U.S. Environmental P r otection Ag ency, Office of Air Quality Planning and Standards, E m issions Measurem ent Center, FR69 vol. 7. pp. 1785-1821. January 12, 2004. 20. US EPA PS- 10. Proposed Perform a nce Speci fication 10 – Specifi cations and Test Procedures f o r Multi-Metals Continuous M onitoring System s at St ationary Sources. U.S. Environm ental Pro t ection Age n cy, Of f i ce of Air Quality Planning and Standards, E m issions Measurem ent Center, August 1997. 21. Chester Lab N et. 12242 SW Garden Place Tigard , Oregon 97223 ph. 503.624.2183 22. EPA Test Method 301, Field Validation of Pollution Measurem ent Methods for Various Media, 40 CFR 56, 27371. June 13, 1991. 23. Pall Life Sciences. 2003. Laborato r y F iltration an d Separation Catalog. pp. 30-31. 24. CES. 2005. Pro-11 Filter used by CES’ Xact Multi-Metals Continuous Em issions Monitor. http://www.cooperenvironm ental.co m / products.htm l. 25. Dry Cal DC Lite Prim ary Flow Calibrators. Found on the web at http://www.drycal.com / d rycal/index.htm

. 26. Handbook of Che m istry and Physics. 65 th Edition

. W e ight in Gram s of a Cubic Mete r of a Saturated Aqueous Vapor (F rom Sm ithsonian Tables). p. E-37. 27. Currie, L.A. 1978. “Detection and Q u antitation in X-ray Fluorescence S p ectrom e try. in X-ray Fluorescence Analysis of E nvironm ental Sam p les. T. G. Dzubay (ed). Ann Arbor Science Publishers, Inc. pp. 289-306.

M e thod 301 E v al. : V1. 0 S e c t i o n 1 0

. 0 R e f e r e n c e s Page 74 of 7528. Seinfeld, J.H., S.N. Pandis. 1998. Atm o s pheric Che m istry and Physics. Page 10. Elevation of incinerator is about 630 ft. 29. Paule, R.C., G. Marinenko, M. Knoerdel, and W

. F. Koch. Jan 1986. Ruggedness Testing – Part I: Ignoring Interactions. Journal of Research of the National Bureau of Standards. Vol. 91. No. 1. pp. 3-8. 30. Paule, R.C., G. Marinenko, M. Knoerdel, and W

. F. Koch. Jan 1986. Ruggedness Testing – Part II – Recognizing Interacti ons. Journal of Research of the National Bureau of Standards. Vol. 91. No. 1. pp. 9-16. 31. Ahm e d, K. of Pall Corporation personal co mm unication to CES’ B.E. J ohnsen June 3, 2005. Results of Air T echniques T DA-100A standard DOP Test. 32. US EPA PS- 11. Performance Specification 12 a – Specifications and Test Procedures for Total Vapor Phase Mercury Conti nuous Em issions Monitoring System s in Stationary S ources. U.S. Environm e n tal Protection Agency, Office of Air Quality Planning and Standards, Em issions Measurem ent Center, F R 69. pp. 4701-4750. Appendix B Part 60 Jan. 30 2004. 33. Cooper, J.A., B.E. Johnsen, P. Ginochio. April 2005. Re-design and Field Testing of an X-Ray Fluorescen ce Multi-Metals Monito r at the Iowa Army Ammuni tion Plant, Middleton, Iowa Coal Fired Boiler. S u bm itte d to US Ar m y Corp of Engineers: Engineer Research and De velopm ent Center under c ontract no. W 9132T- 04-P-0065. 34. Hay, K.J., V.M. Boddu, B.E. Johnsen, J.A. Cooper. January 2005. Report No. ERDC/CERL-TR-05-3. X-Ray Fluorescence-Bas ed Multi-M e tal Continuo us Em ission Monitor Technology Demonstration. US Ar m y Corps of Engineers: Engineer Research a nd Developm ent Center. 35. EPA Compe ndium of M e thods for the De term ination of Inorganic Com p ounds in Am bient Air. June, 1999. Com p endium Method IO-3.4 Determ ination of Metals in Am bient Particulate Matter Using Inductiv ely Coupled Plasm a (ICP) Spectroscopy. EPA/625/R-96/010a. 36. Scott Specialty Gases. S c ott Gas Mixtur es Data: Gas and Li quid Mixture Basics. Plum steadville, PA: Scott Specialty Gases; 2004

.

M e thod 301 E v al. : V1. 0 S e c t i o n 1 0

. 0 R e f e r e n c e s Page 75 of 75