## CES Response to Veolia Incinerator Comments **Summary** Most of the issues raised in the comments were addressed in the Alternative Monitoring Petitions submitted by Eli Lilly and Company in 2005 , particularly “ Method 301 Evaluation of Candidate Conditional Methods” and more specifically Section 7.0 “ Range of Method Application ” which is presented in the Appendix of these comments. This appendix demonstrates the robustness of the Xact met hodology and instrumentation over a broad range of source conditions. The remaining comments relate to the commercial viability of the Xact. CES conditions of sale are no different than those of other manufacturers of pollution control and monitoring ins trumentation. These results plus those in the Appendix clearly show that the Xact has demonstrated its ability to operate accurately and reliably for extended periods of time under a wide range of stack conditions that includes those likely to be found in the Veolia stack, and that such monitors are commercially available from Cooper Environmental Services LLC. 

### 1. **Ap p**  **licability**

**to Veolia Incinerator** a. **Comment** : **#48 Comment:** OTM 16 and 20 are site
- specific methods and are not applicable to Veolia’s operations. OTM 16 and 20 were written specifically for Eli Lilly and Co.’s (Lilly) source and instrument. Wh ile they would provide a starting place for another facility to devel op their own site
- specific method, one cannot assume that either could be used at another facility without significant modification. For example, the sample transport system in OTM 16 provides for a protocol for including the sample transport system into t he instrument validation using either dynamic spiking of known gases or comparison to another method (instrumental or reference, M29, filters/tubes and Ohio Luminex, etc.). This was written specifically for the Lilly system using a Sigrist sampling system

. It is not at all clear that an appropriate sample transport system could be designed and developed for Veolia’s stack gas conditions. Lilly spent considerable time and resources in developing both the laboratory and stack data underlying these methods. It is also not clear whether this instrument would tie into Veolia’s daily operations, alarms, and QA/QC procedures. It is likely that these two OTMs would need extensive work before they would be usable for the conditions in Veolia’s stack. In additio n, there is a good chance that the current QAG will not be able to produce quantitative mass of metals in the ranges required to calibrate/test the Xact. The QAG operates as a dynamic spiking into the probe/sample loop of the Xact system. Operation of th is unit is dependent on the type of probe used, the flow in the sample loop, and gas conditions. Lilly spent a year developing this device to present the mass of metals specific to its sample loop (f low/moisture, etc.).**b. Response:**  i. The above comment basically states that the demonstrated applicability of the Xact multi
- metals CEMS (Xact) is based on site
- specific testing that is not applicable to Veolia’s incinerator without significant modifications; and that the QAG has not demonst rated an adequate range. ii. Our general response to the site specific concern is summarized in the Appendix (Section 7.0), which discusses the broad range of sources and conditions to which the Xact has been successfully applied. It is important to emphasi ze that while these procedures were developed at Lilly’s stack, there is nothing in them that is specific to Lilly’s stack. Instead, they provide a general procedure that can be applied in many locations. In fact the Xact and its procedures have bee n successfully applied to coal combustion sources equipped with a baghouse and a wet scrubber under an EPA SBIR project with great success (EPA Contract Number EPD07026). iii. Transport systems for th e Xact have been developed for many different sampling conditi ons including at Lilly (downstream of a wet scrubber and a natural gas fired source), coal fired power plants
- downstream of multiple control types including baghouses in combination with wet scrubbers, ESPs alone, and downstream of ESP's and wet scrubbers and with bituminuous, sub
- bituminous and lignite fuels at munitions incinerators
- Diesel fired sources downstream of a baghouse. Appropriate transport systems were installed at all of these locations. iv. QAG: It is difficult to understand where the comme nter came to the conclusion that “...there is a good chance that the current QAG will not be able to produce quantitative mass of metals in the ranges required ...”. Contrary to this statement, the QAG has been used to generate metals aerosols whose concentra tions are traceable to NIST standards in the range of ng/m3 (used for the ambient/fence line Xact monitors) to mg/m3 used for stack monitors. This clearly covers the range required for any multi
- metals CEMS based on the emission limits required as well as maximum concentrations expected. The QAG is broadly applicable to ambient as well as stack monitors and its application is independent of such conditions as the type of probe, probe flow or gas conditions. The QAG operating conditions can readily be adj usted to these variables in the field to deliver the concentration to meet the required permit range. The QAG can be mobilized and delivered for field work within days of receiving a purchase order for services. 

### 2. **Statement of Basis**
**– A**  **: Commercial A vailab**  **ility** a. **Comment:** EPA’s statement that “Multi
- metals CEMS are commercially available and have been demonstrated to be reliable for measuring mercury and other metalemissions from hazardous waste combustors” (Statement of Basis at 22) is incorrect or mislead ing. W hen the Statement of Basis was written, the Xact was offered by Pall Corporation. This is no longer correct. Pall no longer manufactures and sells the Xact unit. The marketing rights to the Xact have reverted to Cooper Environmental Services. It shou ld also be noted that this instrument is not an instrument that is carried in inventory. If a facility wanted to purchase an Xact unit, Cooper Environmental Services has indicated that it would take them at least six months to build it. This is the time to build the instrument itself and does not include time to develop the site
- specific sampling train or the time to develop the software interface between the instrument and the facility’s control systems. The software development process (custom sof tware fo r that site) would take several months after the instrument was installed. Only one Xact unit has been installed and operated for an extended period of time at only one hazardous waste combustor, the combustor at Evoniks Tippecanoe Laboratories. Due to fre quent maintenance issues and equipment failure, that Xact unit is no longer operating. (CRWI 6
- 7) **b. Response:**  i. The fact that t he marketing rights to the Xact have reverted back t o Cooper Environmental Services LLC (CES) has little to do with its commercial availability. CES is the company that developed and first commercialized the Xact series of monitors and is having no problem returning to this position. In fact, CES took its first new order for an Xact at the end of March of this year and will be shipping that Xact by the end of this month (May, 2013). The fact that CES may have given a longer shipping time shortly after CES was informed of the return of the Xact rights to CE S would have been because of the uncertainties associated with this time period. Now that contracts are in place with supply vendors, the uncertaint ies have been greatly reduced and the delivery times reduced. ii. The fact that Xacts are not carried in inven tor is not unusual in contemporary business, particularly for high end environmental instruments for which the condition, metals, requirements, etc. may be somewhat different for each source. Three to six months is not uncommon. As noted above, the longe r lead times were associated with the initial uncertainties shortly after CES was informed of the Pall decision. iii. Once a purchase order is received, many of the fabrication tasks can be conducted in parallel/simultaneously. As such, components such as prob e and transport lines are included in CES’ time estimates and it isn’t necessary to wait until the unit is delivered. Similarly, although the DAHS interface maybe site specific, the DAHS software development process could begin immediately as the Xact ut ilizes standard communication protocols (Modbus) and has fixed and known register locations for data.iv. The Xact operated reliably for 6 plus years at Lilly Tippecanoe laboratories incinerator as well as a year under Evonik. It is our understanding that Evon ik elected not to complete a required repair on the Xact because there was not a regulatory requirement to operate the instrument. Below are summaries of the Xact's XRF audit and RATA results during its operation at Lilly. (CRWI 6

- 7)

**Xact Quarterly A udit results Results** 

**Xact RATA Results**

In addition, similar CES multi
- metal CEMS have been installed and operated on US Army hazardous waste incinerators. 

### 3. **Lack of Data Demonstrating A pplicability**  **at Veolia Moisture Conditions**  a. **Comment:** 1
- The Statement of Basis states in subsection 4.0(D)(c): “Eli Lilly's stack gases at the Tippecanoe facility averaged approximately 8 percent moisture content and 140 degree F while the multi
- metals CEMS was being operated. However, Pall Corporation has assured EPA that trial tests on its CEMS demonstrate that the unit can operate reliably at moisture contents above 40 percent. The only document in the record produced by EPA to This image cannot currently be displayed.

This image cannot currently be displayed.support this statement is one email exchanged between Pall and EPA. EPA failed to c onsider the fact that Pall, which manufactures the multi
- metals CEMS, has a financial interest to overstate the CEMS capabilities. No data or objective evidence exist in the record to demonstrate the Xact multi
- metals CEMS can operate at moisture contents at or above 40 percent.

**b. Response:**  i. As noted in the Appendix (Section 7.0 of the Lilly AMP), the Xact has operated at a wide range of temperature and moisture conditions. ii. It has operated successfully on saturated stacks at 125 to 140 degrees C (SBIR stu dy and a coal fired power plant). iii. Clearly, it should have no problem operating at the conditions in the Veolia stack. 

### 4. **Statement of Basis**
**– B**  a. **Comment:** 2
- The Xact Multi
- Metals CEMS is identified in the Statement of Basis as a system that uses reel
- to
- reel filler tape sampling technology followed by X
- ray fluorescence analysis of metals in the deposit. The Statement of Basis represents that this is the only multi
- metals CEMS technology currently commercially available. Pall Corporation is identified in the Statement of Basis as the marketer for the Xact multi
- metals CEMS. The Statement of Basis discusses the use of a Xact CEMS at the former Eli Lilly incinerator. Eli Lilly's incinerator and Veolia's Unit 3 are not comparable. Most incinerators in cluding the Eli Lilly incinerator employ wet scrubbers as their pollution control equip m ent or a combination of wet scrubbers and baghouses. The off gases from incinerators using wet scrubbers have similar moisture and temperature ranges. The suppliers of die Xact multi
- metals CEMS claim that the Xact analyzes the off gas emitted from an incinerator to determine the amount of metals in the emissions stream. Unlike these wet scrubber systems, Veolia operates a dry pollution control system on Units 2, 3 and 4 of it s Sauget facility. Dry systems are unique and to my knowledge the only other exclusively dry system in the United States is the Clean Harbors incinerator in Kimball, Nebraska. Veolia's dry pollution control systems operate at much higher moisture and tem perature ranges than wet scrubber systems. The Xact multi
metals CEMS has never been demonstrated to successfully operate in the high moisture and high temperature environment presented by Unit 3. **b. Response:**  i. As noted in the Appendix (Section 7.0 of the Lilly AMP), the Xact has operated at a wide range of temperature and moisture conditions. ii. More specifically, the Xact has demonstrated operation at temperatures up to about 500 degrees F (demilitarization incinerator) and in flue gases saturated at 140 deg rees F.iii. Below in the following figure, are the results of a comparison of mercury results reported by EPA reference method 30B and the CES Xact. This data was collected at a coal fired utility boiler operating with dry controls at about 350 degrees F. iv. These results plus those in the Appendix clearly show that the Xact has demonstrated its ability to operate accurately and reliably for extended periods of time under a wide range of stack conditions that includes those likely to be found in the Veolia stack.



### 0 1 2 3 4 5 6 7 8 9 10

0 1 2 3 4 5 6 7 8 9 10 11 12 13 **RA TA** **N um**  **be r** **M e** **r c** **u r** **y C** **o n** **c .** **(****g /** **d s** **c m** **)**



### Xa ct Meth od 30 B 

# 3.53% RELA

**TIVE ACCURACY** 

### Ap **pendix**

**7.0 Range**  **of Method**  **Application** 7.1 Overview The results from the preceding secti o n clearl y demonstrate th e ability of the XFM and Xact

IAP to accuratel y and precisely quantify m etals in stack e missions over a broad ran g e of concentrations, and that these m ethods are appl i cable to the quantitative measure m ent of the five validated m etals in hazardous w aste inc i 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 s ampling and analy sis procedures depend on and respond to changes in e mission chara c teristics associated with different source categories. The EPA suggests in Method 301 that this mi ght be addressed in part by conducting a series of ruggedness tests, which are laboratory tests of a m ethod’s sensiti v ity to key m ethod variables 1 , 29 , 30

. This ty

pe 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 reactive

- filter based technology is also available that supports the general applicability of these m e thods to most sources and ele m ents. The above tests and data are summ arized in this section along with key aspects of the XFM and Xact

- IAP m ethods, and relative characteri stics of e missions. The objective of this review is to de monstrate that these m ethods should be considered generally applicable to a wide range of e missions and elem ents including those from r e gulated sources. This review is presented in the f

ollowi ng subsectio n s:

• Method Applicability (7.2)

• Key

S am pling and Anal ysis Features (7.3)

• Key

Emission Characteristics (7.4)

• Filter Trappi ng Efficiency for Vapor Phase Metals (7.5)

• Applicable Concentration Range (7.6)• Deposit St a bility (7. 7 )

• Moisture (7

. 8)

• Holding Ti m es (7.9)

• Other Related Tests (7.10)

• Applicable Ele m ents (7.11)

• Sensiti v ity to Reactive S t ack Gases (7.12) The details of this review are presented in Appendix L and supporting reports are provided in Appendix M. The conclusion of this review is that there is a substantial body of infor m ation about the che mistry and phy sics of the m ethods and e missions as well as specific test data covering so m e of the more ch allenging of conditions that strongly supports the extension of these m ethods to other regulated source categories and elements. 7.2 Criteria for Candidate Method Applicability It is clear that when a candidate m ethod m eets the require m ents of Method 301, it is valid for the source tested, and m ay be applicable to the specific source category
. Method 301 recomm ends that addi ti onal t e st d ata be sub m itted to extend the applicability of the c andidate m ethod to other source categories. This rec o mmendation, however, does not specify criteria that can be used to evaluate possible extens i on of a m ethod’s applicability when direct test data is not available. For the following dis cussion, it will be assum ed that the candidate m ethods will be applica

b le to an untested source categ o ry if differences in e mission characteristics between s ources tested and candi date source e missions are such that they are unlikely to contribute significantly to i m precision and bias in m easured metal concentrations. 7.3 Key Sampling and Analysis Features Both the XFM and Xact

- IAP draw a represent a tive sam ple of stack gas through a filter m atrix where m etals are concentrated prior to anal ysis. The XFM draws th e stack g as through an u

pstream PTFE filter th at re moves PM from a gas stream and then through a downstream reactive filter that traps vapor phase m etals. The Xact

- IAP, on the other hand, uses a single reactive filter to trap both the PM and vapor phase m etals. Both m ethods m easure the m ass of each m etal dep osited on th e filter(s) u s ing XRF anal ys is pro c ed ures based on EPA’s IO Compendium Method 3.3 14

. The concentration of m etal in stack gas ( C ) is c alcul at ed by

dividing the m ass of m etal in the f ilter (s) d ep osit ( M) by

the volum e of stack gas (V) th at passed thro u gh the f ilter ( s). That is; C = M V **Equation 26**  Key sam pling and anal ys is features are thus tho s e that co ntrib ute to the qu antitati v e ac curacy of the m etal m ass and volum e determinations. Consequently , a m ethod w i ll likely be applicable to a particular source e missions cate g ory if the di f f erences in s t ack gas characteristics are s u ch that they do not significantly co ntrib ute to inaccuracies in v o lum e and m ass measurem ents.In the case o f volum e deter mination, both m ethods dilute, co o l , filter, and dry the s t ack gas as well as denude the gas of corrosive species such as acids, S O 2 , etc. prior to volum e deter mination. This dilution and extensive c onditioning of the stack gas prior to volume deter minati o n m akes it relatively in s ensitive to di fferences in stack gas c h aracteristics. Thus, if differences in stack gas c h aracteri s tics are to significantly impact the accuracy of th e m easured aerosol concentration, it must be through the m etal m ass deter mination. Accurate d eter

mination o f m etal m ass dep ends on two key factors, which m ay depend on stack gas c h aracteristics:

• XRF anal ytical d e ter mination of m etal m ass in th e f ilt er dep o sit

• Filt er trapping e ff i cien c y Again, it is important to note th at both m ethods use dilution to m aintain and control such sam pling conditions as te m

peratur e, dew point, and PM concentration in their opti m al range. As such, the m ethod’s sensiti v ity to s pecific s t ack gas characteri s tics is si gnificantly reduced even for these two factors. For example, when applying these m ethods, the applications engineer is directed to adjust non - critical param eters within s p ecified li mits such as dilution ratio and sampling ti m e to opti mize the m ethod for a particular app l ication. Further more, since there is no direct interaction between s t ack gas and the analy sis, the XRF deter mination of m etal m a ss in the filter deposit is only indirectly dependent on the c h aract eri s tics of the stack gas through how the stack gas impacts the characteristics of the deposit on the filter. Other than the anal y t e metals of interest, th e only species d ep o sited on the f ilter are n o n - anal yt e PM species, the total m ass of which is controlled through the m ethod application by selecting opti m al s am

pling ti m es and dilution rati os. None of the m ajor co m ponents of stack gas are trapped on the filters and cannot th erefore interfere with the XRF anal ys is. For this rea s on, the onl y factor that might be s ensitive to stack gas characteristics is th e filter trapp i ng e ff

i ciency f or P M and vapor phase m etals. Filt er tra p ping e ff i cien cies f

or PM are well established and generally ac c epted to be greater than 99% 23 , 3 1 are not expected to be dependent o n di ff

erenc e s in st a ck g a s chara ct eri s tics. As su c h, f ilter tra p ping e ff i cien cy f or vapor phase m etals is the key factor that mi ght be i m pacted by stack gas characteristics. The pri m ary focus of the next two sections is on the potential dependence of vapor phase m etal trapping efficiency on flue gas conditions and the available data showing the range within which the method has demonstrated acceptable quantitation. 7.4 Key Emission Characteristics Characterization of e missions depends on such factors as source ty pe (combustion, process, fuel ty pe, etc.), ty

pe of e missions (ducted or fugitive) and ty pe of controls (filtration, electrostatic precipitat o rs, scrubbers, absorbers, reactive, etc.). However, from the m ethod appli c ability evalu ation perspe c ti v e, the characteristics of em i ssions that are most relevant are those defined in ter

m s of their phy sical (primaril y te m perature) and che mical (co m positi o n) characteristics. Emis s i ons are g en erally co m p osed of varying amounts of air (N 2 , O 2 ), combustion products (N O x , S O x , C O 2 , CO, H 2 O, e t c.), contributions from controls (Na, Ca, H 2 O, NH 3 , etc.) and various process species, and can be further divided into categ o ries such as PM, reactive and no n - reacti v e gases, acid vapors, etc.**S p**  **ecies Phase**  **II T**  **ip p**  **e, IN**  **C F**  **PP -**  **CES**

**Boar dm**  **a n**  **, O**  **R C**  **F PP**  **- E**  **P A** 

**M i**  **d w**  **est H**  **W C**  **- T**  **E A** **D**

**T oo**  **e l**  **e, UT**  C O , d ry O 2 , d ry C O 2 , dry N O x , dry S O 2 , dry HCl ( e q uiv. ) , d ry H 2 O PM @ 7% O 2 T e m p p p m

% % p p m p p m p p m % m g /d sc m °F 14

11 6 110 ND 2 9 4 170 < 10

4.5 12.5 200 225 NA 10 27 300 NA

12
- 15 4
- 8 70 20
- 35 NA 15
- 20% NA 160 10

14
- 15 5 1 2 00 10 50 5 10 4 5 0 As discussed above, the filters used b y the XFM and Xact

- IAP have a high PM m etals trapp i ng efficiency regardless of the stack gas p hys ical and che mical characteristics when sam pling within th e co n ditions spe c i f ied by their SOPs. S o me potential exists, however, for the vapor phase collection efficiency to be i m pacted by the stack gas ph ys ical param eters and che mical composition. F or both the XFM and Xact

- IAP, the sam pling temperature, f

l ow rate, and pressures are controlled by the operat or within the bounds of the SOP and are independent of the source ty

pe. Thus, the key c h aracteristics of e m issions that mi ght impact the re active f ilter ’s trapp i ng e ff

i cien c y are th e s ampling int erf erences ca

u sed by re a ctive gases such as NO x , S O x , NH 3 , C l 2 , HCl, HNO 3 , and H 2 S O 4 . Although this list is not co m plete, it does represent the more abundant and more reactive species likely to be present at varying concentrations in most stacks of regulatory interest. Ox ygen was not listed, since it is expected to be present in most e missions at am bient concentrations (21%) or less, and laboratory tests in Phase I de monstrated high trapping efficien cy at th e hi ghest likely O 2 concentrati o n. Potentially int erf ering rea c tive g as es are li s ted below in Table 23 along with m easured stack gas concentrations during supple m ental testing discussed below and in Appendix L. Although this list is inco m plete, the concentrations and co n ditions are representative of these sources and cover a broad range of c oncentratio n s and te m peratures. **Table 23. List**  **of stack condit i**  **ons for**  **w hich**  **Xact -**  **IAP and XFM**  **tests have**  **been conducted** 

NA: N o t Available C F P P
- CES: CES s p on s o red c oll e c tion e ff i c i en c y te s t at P G E C F PP ND: N o t Dete c ted C F P P
- EPA: EPA s p on s o red te s t of Hg m onito rs H W C
- T EAD: US Ar m y s pon s o red te s ts at de m il i te r i zation H W C 7.5 Filter Trap

p ing Efficien cy for Vapor Phase Meta ls The Clean Air Act li s ts 1 1 m etals as air tox i cs: S b, As, Be, Cd, Cr, Co, Pb, Mn, Hg, Ni and Se 10

. Of the s e m etals, Hg is the o n ly one that is predo minately in the vapor phase at the operating temperature of the Xact

- IAP and X F M (180°F). For this reason, Hg is the most challenging to trap by

filtration and most sensitive indicator of vapor phase m etal trapping efficiency

. Over the pa s t several ye ars, three s eries of Hg trapping and relative accuracy tests have been conducted in addition to P hase I and II tests described in the first part of this report. Whereas Phase II tests de monstrated high Hg trapping efficiencies under conditions more repre s entative of e miss i ons from modern hazardous waste i n cinerators, the s e additio n al tests focused on e missions from coal

- fired boilers. The supple m ental tests were more challenging in part because of their lower Hg concentratio n s (<10 μg/dsc m) but also because of the presence of higher concentrations (Table 23) of potentially interfering species s uch asNO x , S O 2 , S O 3 , NH 3 , PM, etc. The first series of tests discussed below were sponsored by

CES and w ere conducted both in the laboratory and at a coal

- fired utility boiler to de f i ne the concentrati o n range of applica b ility for the rea ctive filters. The second and third s eries of tests were sponsored by

the EPA and the ar

my, and focused on relative accuracy of the m easurem ents at coal

- fired boiler emissions. In the foll o wing summaries, an accep table relative accuracy when co m pared to an EPA authorized reference m ethod will be taken to i m ply an acceptable vap o r phase tra p ping efficien cy . The supple m ental tests summ arized below are discussed in m ore detail in App endix L and supporting reports are provided in Appendix M. 7.5.1 CES Sponsored Trapping Efficiency Tests A series of tests were conducted at CES and a coal

- fired power plant in B oardm an, OR to evaluate the Hg trapping efficiency of reactive filters under a variety of sampling con ditions. For these te s t s, m ercury was inje c t ed into e ither laboratory air or stack effluent and the trapp i ng e ff i ciency e v alu ated with th e XFM using two rea c tive f ilt ers in seri e s. The m ercury trap p i ng efficiency was deter

mined by co m pari ng the Hg trapped on the upstream f ilter with the total m ercury collected on both filters. Mercuric c h lo ri de laborat o ry t e sts in the tem perature range between 100 and 212°F exhibited capture efficiencies greater than 99% for concentrations ranging in excess of 800 μ g/dscm with sampling ti m es up to one hour. Si milar tests were conducted at the coal

- fired power plant using ele m ent al Hg spiked into the stack gas. In this case, the elem ental Hg trapping efficiency was greater than 99% for concentrations ranging up to 300 μg/dsc m . 7.5.2 EPA Sponsored Relative Accuracy Tests CES tested the XFM filter appro ach during an E PA sponsored evaluation of m ercury m easure m ent m ethods at a Midwest coal

- fired power plant5. These tests, conducted in July 2003, co m

p ared si m ultaneous XFM and Ontario

- Hydro Reference Method (OH) m easured m ercury concentrations between 1 and 6 μ g/dscm. The accuracy of the reactive filter based m ethods at low concentrations was de monstrated using an in

- stack version of the XFM. A total of 12 two

- hour OH runs were conducted. F or each OH run, two simultaneo u s 50 mi nute, in

- stack XFM samples were collected by CES. For these te s t s, the XFM and the OH results were in good agreem ent with a relative a c curacy of 11% for the nine valid runs, well within the 20% criteria f

or conditional m e t

hods specified by

EPA’s proposed Perform ance Specificati o n 1 2 32

. Thre e of the 12 OH test runs were o mitted f rom comparison by

the EPA contractors. Two were o mitted because of poor OH replication (>40% difference) an d one was o mitted due to a plant upset. Th e re m ain i ng nine runs were used for co m parison, the results of which are plotted in Figure 19. The high correlation of these results and low rel ative accuracy de monstrat es th e effecti v en e ss o f the rea c ti v e filt er approach for tra p ping and quantifying Hg concentrations between 1 and 6 μ g/dscm.**X F** **M C** **o n** **c .** **( μ** **g /** **d s** **c m** **)** 6
5 n = 9
4 RA = 11% **M e**  **r c**  **u r** 

**y**

3
2 y = 0

. 908x + 0

. 152 1 R 2 = 0

. 962 0 0 1 2 3 4 5 6 **O H**  **C o**  **n c**  **. (**  **μ g**  **/ d**  **sc m** **) Figure**  **19. Comparison of Hg co**  **n centrations**  **determined by XFM**  **and Ontario Hydro** 

**reference method at a**  **coal -**  **fired p**  **o w**  **er plant.**  7.5.3 US Army Sponsored Relative Accuracy Tests The U.S. Army sponsored a series of tests in January 2005 to evaluate a mercury- opti mized Xact at a c o al

- fired power plant 33

. F or these tests, m ercury and arsenic were spiked into stack gas followed by

si m ultaneous Hg and As m easure m ents using the Xact and Reference Method 29. The results from these tests de mon s trated relative accuracies of 17% for these two elem ents, m eeting the proposed 20% criteria proposed for Perfor m ance Specification 10. 7.5.4 Summary of Trapping Efficiency Sen s itivity to Reactive Stack Gases Unlike the p hy sic al f

iltration m echanism used to collect particulate m etals, vapor phase m etals react with the c he mically tre ated filt er and bind to th e filter sub s trat e. So m e sta c k gas constituents could potentially interfere with this process. H o wever, the more abundant stack gas species s uch as N 2 , O 2 , C O 2 , CO, and vapor phase H 2 O are relati v ely inert, are not trapped on the reactive f

ilter, and te s t res ults indicate that th ey do not influence the filter trapp i ng efficiency

. Oxidants with in the gas s tream such as C l 2 have been shown to improve the vapor p h ase collecti o n efficiency for Hg. Other mi nor stack gas co mp onents such as NO x , S O x , and NH 3 , have the potential to int erf ere with vapor phase Hg trapping efficiency . However, this potenti al to int erf

ere h as not b een observed in the extensi v e te s ting th at has been conducted to date. For exam

ple, the possibility of NH 3 interferen ce was evaluated during EPA’s test of m ercury m easure m ent app roaches at a M i dwest coal

- fired power plant with state
- o f

- the

- art ammonia injecti on and selective catal ytic reduction NO x control equip m ent 34

. Despite the use of ammonia, the XF M reactive f ilter de monstrated an 1 1 % relative accuracy when co m pared to the Ontario

- Hydro Hg reference m ethod concentrations, which ranged from 1 to 6 μ g/dsc m . Si milarly , minor reactive co m ponents such as N O x , and S O x have the potential to i m pact vapor phase c o llection efficiency

. However, there is no indication th at these species affected the Hg tr a pping efficiency at the c on c entrations listed in Table 22. Indeed, the 99+% trapping efficiency for ele m ental Hg at the B oardm an site was co m pleted 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 concentrations during Phase I and II testing was greater7

than 50 PPM. The tests conducted to date and the range of key test param eters are summarized below in Table 24. **Table 24. List**  **of test c o**  **nditions a**  **n d references**  **used to e v**  **aluate met**  **h od applicability.**  **P a**  **ra m**  **e t**  **er Concent**  **ra t**  **ion R**  **a ng**  **e T**  **e st**  **S umm**  **ar y**  **T e**  **st** Pa rt i c u l ate M et al s 3
- 2 2 0 0 μg/ d sc m 1, 2 E le m e n t al Merc ury 1
- 3 14 μ g /ds c m 3, 4 O x id i ze d Merc u ry 1
- 8 80 μ g /ds c m 3, 5 **Holdi n**  **g T**  **i m**  **e** X F M : P a rt i c u la te F il t er 1 2 M o n ths 6, 7 X F M: Vapor Pha s e F i lter 2 4 M o n th s a 8 Xa c t 1 2 Mo n ths 6, 7, 8, 9 **Sta c**  **k T**  **y pe**  **& Conditions**  Moi s tu r e F i l t ers a cc ep t a b le fo r W et Stac k s 3, 1 0 , 1 1 F i l t ers a cc ep t a b le fo r Dr y S t a c k s 1, 2, 4, 9 H W C F i l t ers a cc ep t a b le fo r H W C a p p l i c a t i o n s 1, 2, 9, 1 1 CFPP F i l t ers a cc ep t a b le fo r CF P P a pp li c a t i o ns 3 , 4 , 10 **Sta c**  **k T**  **e mper** **a t**  **u r** **e** 4 50 ° F 1, 2 **Filter T**  **emp er** **ature** X F M P art i c u l a t e F il ter 4 00 ° F 12 X F M V a p or Ph a s e F i l t er 1 85 ° F 4, 5 X a c t P a rt i c u la te/

V a p or Ph a s e F i l t er 1 85 ° F **S a**  **mpli n**  **g T**  **ime** X F M 6 0 m i n 4, 5 Xact 3 0 m i n 10 **S a**  **mpli n**  **g Flow**  **Rate** X F M 4 .5 lp m / c m 2 4, 12 X a ct 2 .4 lp m / c m 2 12 **Fie l**  **d Blank**  De t

. L i m i ts l e s s th a n 2 μg/d sc m b 11 a) Corre c t i o n fa c t o r of 0. 5 % / m o n th r e q u ire d a ft e r s ix m o n t h s
. b) One
- s i g m a l i m i ts b a s e d u p o n a n a l y s i s o f 3 899 f il t e rs m e a s u r e m e n ts at L ill y's T 1 49 In c i n e rat o r

1 H W C at T EA D p rod u c t i on f u r n a c e ( Se c tio n 2

. 3 )

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

. 3 )

. 3 E P A t e s t a t M i d w e s t CF P P (S e c t i on 2

. 3). 4 CES T e s t at O reg o n CFPP (Se c t i o n 2. 3 )

. 5 CES L a bora tory T e s t s (Se c t i o n 2

. 3 )

. 6 Re ev a l u a t i on of P h a s e I F i l t ers (S e c t i on 2. 3 )

. 7 E P A P M 2

. 5 S p e c i a t i o n Progra m ; Ree val ua t i o n o f P h a s e I Fi l t e rs ( S e c t io n 2 .3). 8 CES L a bora tory E va l u at io n o f XFM F il ters (S e c t i on 2

. 3). 9 CES Rea n a l y

s i s of X a c t F i l t er T a pe f rom T E A D te s t s (Se c t i o n 2

. 3 )

. 1 0 Xa c t T e s t a t I A

AP CF P P (S e c t i on 2. 3 )

. 1 1 E val ua t i o n o f B l a nk Fi l t e rs at L il l y's T 1 4 9 I n c i n e ra tor (S e c t i on 2

. 3). 1 2 M a n u fa c t u r e rs S p e c i f i c at io ns 1 3 P h a s e II T e s ts at L i l l y' s T 1 4 9 I n c i n e ra tor**X a** **c t** **C o** **n c** **. (** **μ g** **/ d** **s c** **m )** 

7.6 Applicable Concentration Range The applicable concentration range for these r e active filter based m ethods was extended to over 2000 μg/dscm during Xact and Reference Method 29 relative accuracy tests conducted in 2002 at an Army hazardous waste test incinerato r3 4

. Twelve Reference Method 29 test runs were conducted while the stack gas Pb concentrations ranged from a low of about 10 μg/dscm to over 2200 μg/dsc m . The results from these twelve tests are co mpared 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 co m pared to the Method 29 results. If these re sults are co m bined with tho s e in the preceding subsection where the H g results were in good agreem ent with the reference m ethod down to almo st 1 μg/dsc m , it is clear that the m ethod is quantitative over at least three o r ders of m agnitude and at concentrations greater than 2200 μg/dsc m .
2 , 5 0 0

2 , 0 0 0

1 , 5 0 0 n = 12 RA = 4 % **L e**  **ad**

1 , 0 0 0

5 0 0

0 y = 1

. 0 5 8 5 x + 1

. 2 181

R 2 = 0

. 99 9 7
0 50 0 1 , 0 0 0 1 , 50 0 2 , 00 0 2 , 5 0 0 **M e**  **t ho**  **d 2**  **9 C**  **o n**  **c .**  **( μ**  **g/d s**  **c m** **) Figure**  **20 Plot of Xact** **- IAP concentra**  **t ion**  **versus Reference Method**  **29 measured concentrations**  **sho w** **ing excellent**  **agreeme n**  **t over**  **t w**  **o orders of ma**  **g nitude**  **and at**

**concentrations in**  **excess of 2,000 μg/dscm.**  7.7 Deposit Stability The Xact

- IAP uses a reel

- to
- reel tape system to colle c t stack g as m etal s amples, whi c h are then transported to a position for XRF analysis. A f ter analy s is, the tape is drawn over a take up spool where th e exp o sed filter deposits co m e into co nt act with following tape as it wraps over the previously exposed tape. S o m e potential exists f or trans f er of m etals f

rom their origi n al dep osit to the t a

pe covering the deposit. If this tran s f er were s i gn i f

icant, it w o uld reduce the p otential to p ost
- test v alidate Xact

- IAP results with independent anal ys is of the deposits. A s such, post test anal ys es were c onducted on 72 deposits col l ected during relative accuracy tests conducted in May

20 0 2 at a US Army

hazard o us waste pro duction incinerat o r at the Tooele Ar my Depot (TEAD) in Tooele, U T 34

. During these tests, the Xact monitored emissions in an instrum e nt shed about 40 f eet f ro m the incin erator st a ck while EPA Reference Method 29 sam ples were collected at the stack. Tw elve Method 29 test runs were conducted with concentrations varying from 5 to 300 μ g/dscm. There was very good agree m ent with the reference m ethod as illus trated in Figure 21. The relative accuracy was 4% and the results exhibited a high degree of linearity

.**X a** **c t** **C o** **n c** **. (** **μ g** **/ d** **s c** **m )** **L a** **b C** **o n** **c .** **( μ** **g /** **m 3** **) J** **u l** **y ,** **2 0** **0 2** 

Following these tests, the exposed filter tape was s t ored at room te m perature at CES. Two months after the field tests were co m pleted, the tape was re moved from the spool exposing the previously collected deposits. These deposits were cut from the tape and analyzed with CES’ laboratory XRF analyzer. These laboratory results are co m pared to the original concentrations reported by the Xact in Figure 22. Clearly , there is a high degree of agree m ent between the o rigi n al Xact Pb resul t s an d the lab o ratory results. The slope and correlation suggests that there w a s not a significant transfer of Pb from the deposit to the covering tape at the level of a few per cent.

1 6 0 1 4 0 1 2 0 1 0 0 80 n = 1 2 **L e**  **a d** 

y = 1. 0 9 x - 9

. 60 4 0 R 2 = 0

. 9 8 20 0 0 5 0 1 0 0 1 5 0 2 00

**M e**  **t h**  **o d**  **2 9**  **C o**  **n c**  **. (**  **μ g**  **/ d**  **sc m**  **) Figure**  **21. Plot of Pb**  **concentrati o**  **ns de**  **t ermined**  **by Reference Meth**  **o d**  **29 and the Xact.**

180 160 140 n = 7 2 **Lead**

120 100 80 60 4 0 y = 0

. 972 7 x + 3

. 4 259 R 2 = 0

. 9685 20 0 0 5 0 10 0 1 5 0 200

**X ac** **t C**  **o nc**  **. (**  **μ g**  **/ m** **3 )**  **; M**  **ay ,**  **2 0**  **02 Figure**  **22: Comparison of resu l**  **ts from**  **laboratory XRF ana**  **l ysis**  **in July,**  **2002 w** **i th**  **Xact field**  **test results**  **from May**  **2002 relative acc**  **u racy**  **tests at a ha z**  **ardous w**  **aste incinerator** 7.8 Moisture Over the last three years, the Xact

- IAP and XFM have been evaluated on both wet and dry stacks (Table 25) using Method 29, Ontario

- Hydro and the Q AG reference aerosols. Inallcases, th e Xact

- IAP and XFM showed good relati ve accuracy and trap p i ng efficiencies. For

this reason, it is believed that the candidate m easure m ent m ethods are valid for both wet and dry stacks as long as the probe and filter te m perature re m ain above the water vapor dew point, which are controlled pri m arily with dilution. **Table 25: Recent**  **tests o**  **f Xact and XFM on**  **w e**  **t and dry stacks.** 

**D a**  **te Test** 

**L o**  **cati o**  **n Inc.** 

**T y**  **pe Air P**  **o lluti**  **o n** 

**C o**  **nt r**  **o l**  **Techno l**  **o gy**  **Wet or** 

**Dry Stack**  **Elements A**  **n aly** **z ed**  **Results**

March 2 005 Eli Lilly

Lafayette, IN H W C Scr

u b b er Wet As, Cr, C d , H g , P b Xact and XFM within

1 5 % of Q AG p re d icted for As, Cr, Cd, Hg, P b
Jan. 2 005 I AAP Ames,

IA CFPP Scrubber Wet As, Hg Xact RA of 17% v s . M 29 f o r A s , H g Sept. 2 003 TEAD

Tooele, UT H W C High Te m p . Ba gho u se Dry Pb Xact RA of 4% v s . M 2 9 f o r Pb May 2 003 Midwest CFPP Ammonia inj ectio n , SCR, b agh o use Dry Hg XFM R A of 11 % v s . OH f o r Hg Au g 2 002 Boardman,

OR CFPP Scrubber Wet Hgo Trapping e ffic i ency of 9 9 % fo r H go

7.9 Holding Times Tests were also conducted to evalu ate the hol di ng ti m es for the XFM and Xact

- IAP filters. These te s t s included both the XFM PTFE filter and the reactive filter. During th e Dece m ber 2004 Phase I te s t s, th e PTFE filter h ad collec t ed particulate As, Cd, Cr, Hg, and Pb at concentrations ranging from 20 μ g/dscm to 125 μ g/dsc m . In order to d et ermine PTFE f ilter holding ti m e s, CES reanaly zed filters from sev en of these tests (Runs 1

- 4 and 21

- 24) in April 2005. During the five months between the initial and second XRF anal ys is, the filters were stored at ro o m te m

perature in p l astic petrie dishes. Both anal ys es were conducted using XRF following the IO Co m

p e ndium Method 3.3 14

. Overall, the av erage m etal concentrati o ns m easured in April 2005 were within one percent of the concentrations deter mined five months earlier. All m easurem ents were within 4% of their original concentration, with no significant bias. The good replication of the m et al m ass de mo nstrat es the ability of the PTFE f ilter s to ret ain m etal concentratio n s over a f i ve month peri o d. Reactive filter tests were conducted to deter mi ne retention efficiencies and esti m ated holding ti m es for vapor phase metals using Hg as an in di cat o r species. These te s t s are b ased on filters expo s ed to both ele m ental m ercury and m ercuric chl o ride vapors d uring tests conducted in June and August 2002 and filters from coal

- fired power plant flue gas tests. All filters were kept at room te m

perature and anal yz ed using IO Co m pendium Method 3.3 14

. These filters were rean al yz ed periodically o v er th e past two years and were found to have lost on average about 10% of the original m ercury over this period. This finding wasindependent of laboratory or field applicati on, or oxidation state of Hg trapped. A linear model

was developed which assum es the m ercury l o ss from the reactive filter to be co n stant over ti m e. This model showed that, when us i ng a correction factor th at assum es a loss of about 0.5% per month, the m ercury concentrations m easured after two years were, on average, within 10% of the original m ercury concentrations. The good agreem ent for all of these tests s upports th e use of a correction factor of 0.5% per month for filters that have been archived for more than six months. This would allow the hol di ng ti m e to e xtend to at least two years. 7.10 Applicable Elements The XRF anal ys is d et er

mination of m etals in the f ilter d eposit is ba s ed on EPA I O Co m pendium Method 3.3, which is generall y ap p licable to ele m ents with ato mic numbers ranging from about 13 (Al) through 92 (U). This range of ele m ental ap p licability is expected to apply to the XFM PTFE f ilter but not to th e re acti v e f ilter. In the c ase of the rea c tive f ilter, the l o west ato mic num ber el e m ent quanti f

iable with XRF anal ys is is Cr (24) be cause of signi f i cant i m purities in the f

ilter m atrix. The elem ents of pri m ary regulatory interest are those the Clean Air Act Am endm ent s clas s i fy as Air Toxics: i.e. Antimony (Sb), Arsenic ( A s), Beryllium ( Be), Cadmium (Cd), Chro mium (Cr), Cobalt (Co), Lead (Pb), Manganese (Mn ) , Mercury (Hg), Nickel (Ni), and Selenium (Se). These eleven elements have be en sorted by volatility in the Maxi m

um Achievable Control Technology (MACT) rule s 1 7 as f ollows:

• Non

- enum er ated m etal co m pounds (N): Sb, Co, Mn, Ni, Se; equated to particulate m atter in the MACT

• Low volatile m etal co m p ounds (L): As, Be, Cr

• S e mi

- volatile m etal compounds (S): Pb, Cd

• High volatile m etals (V): Hg The m etals tested in Ph a se I and I I represented p articul at e m atter as w e ll a s all of the m etals in the three volatility c ategories except the low volatility ele m ent Be. The other ele m ents not tested are n o n - enum erated m etals, wh ich the EPA has equated to particulate m atter in the MACT rules. Although these eleven ele m ents r epresent the pri m ary focus of this discussion, it is i m portant to note that these filter based m ethods are expected to be applicable to most of the ele m ents listed in E P A IO Co m p endium Methods 3. 3 1 4 and Be by I O Co m pendium Method 3.4 3 5

. 7.11 Other Related Tests 7.11.1 Sample Collection T imes The theore tical sam

pling ti m e f

or the XFM and Xact

- IAP is p ri m arily li mited by f ilt er loading with PM since XRF correcti o n factors m ay be required for high particulate deposit densities. H owever, the f

ilter loadi n g can be co ntrolled in s o urces with h i gh particul at e le v els by adjusting the sam

pling ti m es and dilution ratios up to 4:1. For this reason, it is believedthat, these filter

- based methods can sam ple for p e riods up to f

our ti m es greater than has currentl y been de monstrated; 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 in st alled on the T149 hazard ous waste i n cinerator in May 2004 and operated throughout the summer of 2004. During this ti m e, the Xact co m p leted about 4000 runs while the stack was not burning hazardous waste. These runs were treated as field blanks and were used to stati s tic ally deter mine Xact

- IAP det e ction li mits. These st ati s tic ally deter mined detection li mits were in good agreem ent with those calculated from the analysis of a few filters. **Table 26: Xact det**  **e cti**  **o n**  **limits de**  **t ermined**  **at Lilly’s T1**  **4 9**  **inciner a**  **t o**  **r**

**Elem D**  **E T**  **E C**  **T ION**  **LI M**  **I T**  **S**

**X F**  **M 1**  **Xac t**  **2** μ **g/d scm**  μ **g /dscm**  CR AS CD HG PB MN CO NI SE AG SB CU F E Z N BR SR T L 0.08

0.08 0.80 0.14 0.12 0.08 0.08 0.06 0.08 0.60 1.60 0.08 0.12 0.06 0.20 0.18 0.14 0.3

0.1 2.4 0.3 0.6 0.2 0.3 0.3 0.1 4.2 6.2 0.5 0.9 0.2 0.4 0.3 0.3 1) 95% Confidence, Interference free, 30 mi nute sam ple. 2) 95% of 3899 Xact blank m easurem ents at T149 In cinerator
7.12 Applicable Source Categories As discuss e d earlier, the f ilter - based sam

pling approach has b een succ e ss f ully tested in the laboratory and on two hazardous waste i n cinerators as well as three coal

- fired boilers. Each of these tests showed good rel a tive accuracy and trapping eff i ciencies. Source e missions can be divided into two cat e gorie s : f ugitive and du c ted e missions. Fugiti v e s ources i n clu de e missions from processes such as field

- burning, slag

- pouring, e missions from buildings, demolition a cti v ities, f

o rest f i res, etc. in addition to passive fugiti v e e missions f rom sources such as wi n d

blown du s t and dust s u spended by vehicular traff

i c. These fugiti v e e missions are ty p i c ally charac teri z e d by

substanti ally low e r concentrations of p o ssible reactive s p eciesthan the co n centratio n s in the ducted e missions already successfull y tested. As such, the

XFM and Xact

- IAP should be applicable, in gen eral, to these fugitive e mission sources because the characteristics of their e missions are less challen ging than th e ducted so urces already tested. Ducted sources, on the other hand, can have e mi ssion characteristics si mi lar to those already tested, and in so m e cases m ay exceed the valu es for so m e param eters that m ay be more challenging than tho s e already tested. As discus s ed earli er, th e f ilt er - ba se d approach has shown consistent s u ccess over the pa st few years while sam pling at two hazardous waste incinerators and three c o al

- fired boilers with a wi de range of controls (wet scrubbers, ESPs, high te m perature ceramic baghouses, ammonia injection, selective cataly tic reduction, li m e spray

dryer absorber for SO 2 control, and a f

abric f ilter f or p articul at e co ntrol). In e a c h case the relative accuracy in co m parison to th e QAG, Ontario Hydro, and Method 29 was better than the E P A required 2 0% for conditio n al m ethod consideration. In g eneral, the filter

- based approaches have been accurate regardless of source category , e mission control technology used, moisture content and stack che mistry. As such, the Xact

- IAP and XFM m ethods should be applicable to a w i de range of source categories including incinerators, boilers, kilns, s m elters, plating operations, foundri e s, mi neral processing and other industrial processes using a wide range of pollution control technologies.