## Summary of Comments and Responses on

Revisions to Test Methods and Testing

Regulations

Prepared June 2013

Proposed in the Federal Register on

January 9 , 201 2(This page included to provide for two sided copying)1



## TABLE OF CONTENTS

Section No. Page

1.0 Summary 2

2.0 List of Commenters 3

3.0 Public Comments and Responses 52

1.0 SUMMARY

On January 9, 2012, the U.S. Environmental Protection

Agency (EPA) proposed Revisions to Test Methods and Testing

Regulations . This action promulgated technical and editorial

corrections for source testing of emissions and operations.

Inacc uracies and outdated procedures in the current testing

provisions have been revised, and new alternatives that have

been approved but not incorporated into the test procedures are

being added. These revisions will improve the quality of data

where they are being made and will give testers additional

flexibility to use the newly approved alternative procedures.3

2.0 LIST OF COMMENTERS

Item Number in

EPA

- HQ

- OAR

- 2010

- 0114 Commenter and Affiliation

000 5 Wayne Stollings

Triangle Environmental Services, Inc.

0006 Walter Smith

0007 Source Evaluation Society Newsletter

0008 Procedure for Determining Stratification at CEMS Locations

0009 Byron Nelson

Southern Environmental Sciences, Inc.

0010 Ed Juers III

0011 J.F. Jarrett

0012 Anonymous

0013 Anonymous

0014 Fred Ballay

New Jersey Dept. of Environmental Protection

0015 Kevin McGinn

URS Corporation

0016 Michael A. Klein

New Jersey Dept. of Environmental Protedtion

0017 Fred Ballay

New Jersey Dept. of Environmental Protection

0018 Fred Ballay

New Jersey Dept. of Environmental Protection

0019 Anonymous

0020 Ronnie Watkins

Alabama Dept. of Environmental Management

0021 Michael A. Klein

New Jersey Dept. of Environmental Protection

0028 Melvin E. Keener, Ph.D.

Coalition for Responsible Waste Incineration

0027 John S. Peterson

Delta Air Quality Services

0025 Brian J. Kearney

GenOn Energy

0024 John S. Peterson4

Delta Air Quality Services

0026 John S. Peterson

Delta Air Quality Services

0023 David Elam

Summa Consultants, Inc.

0022 Thomas Maza

Michigan Dept. of Environmental Quality

0029 Barbara A. Walz

Tii

- State Generation and Transmission Association, Inc.

0030 John H. Phillips

Ford Motor Company

0031 Barry Rayfield

RE2 Solutions, LLC

0032 Lauren E. Freeman

Hunton & Williams, LLP

0036 Shannon S. Broome

Katten Muchin Roseman, LLP

0035 Andrew Dicke

GE Energy

0039 Stephen R. Gossett

Eastman Chemical Company

0034 Alice Edwards

Alaska Dept. of Environmental Conservation

0038 Angus E. Crane

North American Insulations Manufacturers Association

0033 Cathe Kalisz

American Petroleum Institute

0040 Alice Alice Edwards

Alaska Dept. of Environmental Conservation

0037 Cathe Kalisz

American Petroleum Institute

0041 Susan M. Clark

Lubrizol Advanced Materials, Inc.

0042 Lauren E. Freeman

Hunton & Williams, LLP

0043 Lauren E. Freeman

Hunton & Williams, LLP

0044 Lauren E. Freeman

Hunton & Williams, LLP56

3.0 PUBLIC COMMENTS AND RESPONSES

Supportive Comments

1. Comment : Two comment er s expressed appreciation for the

a gency 's efforts to amend the rules to reflect advancements in test methods and increase flexibility in determining which method is appropriate for a given situation. One

commenter believe d the changes proposed would provid e better data from source testing of emissions and operations for regulatory compliance determinations. (0030 , 0031 )

Response : No response is necessary.

Parts 60 & 75 Synch

2. Comment : One commenter expressed appreciation for the clarity in requiring evaluation of cyclonic flow in all

cases. The commenter recommended that the EPA m ake such
revisions with an eye to the requirements of both Part 60 and Part 75 test programs. For example, it was recommended

that the stratification test procedures be harmonized as should the applicability of Method 205. Harmonization reduces the need for obtaining approval for case

- by

- case harmonization requests when test programs are undertaken to satisfy both Part 60 and Part 75 objectives. The co mmenter supported the information posted to the docket by commenter
0007 and hope d that the EPA considers their arguments in making a final decision regarding stratification evaluation. (0023)

Response : We attempt to harmonize testing requirements in
Part 60 with those in Part 75 as much as possible. In some cases, such as with Method 205, a method may lend itself to general use under one program but create challenges in established procedures in another program.

3. Comment : A commenter noted that Part 75 reg ulations require bias and drift assessments for the reference methods after each relative accuracy test run. The commenter thought this procedure would more accurately assess performance tha n the proposed allowance to conduct
the tests after a series of runs . The commenter believe d7

the Part 60 and 75 r equirements should be the same because dual compliance is often the case. (0017)

Response : As much as possible, we attempt to write similar

re quirements under both parts. In some cases, however, the flexibilities allowed under Part 60 for showing compliance may not need to be as stringent as the Part 75 requirements due to the nature of the trading program. In cases of showing dual compliance, t he most stringent requirement

should be followed.

Use of Mercury

- Free Equipment

4. Comment : Three commenters expressed approval for allowing
alternatives to mercury containing thermometers and

barometers for both the worker exposure concerns and environmental hazards associated with mercury

. (0023 , 0025 )

Response : No response is necessary.

5. Comment : A commenter felt the terms “equivalent in terms of performance” and “suitably effective” used in the proposal for alternative mercury

- free equipment were ambiguous and vague and would lead to confusion and uncertainty. They suggested the language be modified to include the following: “If in the opinion of an established testing firm, having been in business for 3

- plus years, the alternative thermometer is equivalent in terms of performance or suitably effective, the mercury

free thermometer may be used.”

Response : We do not believe the commenters suggested language added further clarity and the original language was not changed.

Alternati ves to AA Analysis

6. Comment : Two commenters supported the addition of inductively coupled plasma

- atomic emission spectrometry (ICP

- AES) and cold vapor atomic fluorescence spectrometry (CVAFS) as alternatives to atomic absorption (AA) analysis.

T he commenters noted that many labs have been using ICP

- AES for Method 29 for years and have a good established track

record. Both commenter s recommend ed that inductively couple d plasma

- mass spectrometry (ICP

- MS) be allowed as

well for M ethods 12, 104, and 108 since ICP

- AES is becoming
outdated and suffers from various inter

- elemental8

interferences. It was noted that ICP

- MS also offers improved sensitivity and precision

. By allowing both methods, a lab would have the flexibility to sort o ut any sample specific interferences and could provide better data quality than by using ICP

- AES exclusively. (0030, 0031)

Response : We agree with the commenters. We have added ICP

MS as an analytical option to Method s 12, 104, and 108

.

Use of Tedlar Bag Alternatives

7. Comment : One commenter fully support ed the allowance of
other brands of films for sample bags but noted that the preamble was incorrect in stating that Tedlar bags are no longer being produced. The commenter indicated that Tedlar bag manufacturers were having difficulty obtaining Tedlar film in early 2011 due to minimum order restrictions imposed by one Dupont distributor. However, Dupont has actually increased PVF resin production to meet increased
Tedlar film demand for us e in solar panels, and other distributors are still selling Tedlar film to bag manufacturers to support the stack testing and industrial hygiene communities.

The commenter noted that s ome bag manufacturers may not
have the resources to make the suitability determinations for specific applications on alternative bag materials. I t may be more appropriate to indicate in the application that either the tester, the bag manufacturer, or the film

manufacturer should determine the applicability of Tedlar equivalent materials for the compound of interest (prior to use of the alternative material for source testing). The commenter also felt it appropriate to include a provision
in each method that this information be made available for review by the adminis trator over any test program where the alternative sampling bag material is to be used. (0031)

Response : We thank the commenter for this clarifying information on the availability of Tedlar and the need to verify applicability. We will state in the affected methods that alternative bag materials must be verified for their suitability for the compound of interest by t he

manufacturer and this verifying information should be made available for inspection.9

8. Comment : A commenter supports the EPA’s proposed changes to allow for the use of sampling bags made from materials

other than Tedlar. (0033, 0037)

Response : No response is necessary.

Use of Method 320 as an Alternative to Other Methods

9. Comment : A commenter supported the use of Method 320 as an alternative in various applications in most cases. However,
the commenter noted that in recent independent audits of

test programs where Method 320 was used for reactive compounds, there have been cases where testing firms provided inadequate documentation to confirm the method was properly followed. I t was suggested that Method 320 be

amended to include a required QA/QC reporting section so any reviewer or administrator is provided with adequate
information to confirm the results are correct.

The commenter noted that in past experience, test reviews have shown such deficiencies as inadequate sampling equipment and that recovery checks have failed to detect
bias that should have been obvious. It was noted that the design and materials of construction for a sample introduction system feeding gases into an FTIR are critical to successful sampling with this method , and rece nt data suggest this method needs to be strengthened so all sampling biases are thoroughly taken into account and
documented when the method is used for certain reactive gases (NO, NO 2 , SO 2 , SO 3 , HF, etc.). (0031)

Response : The commenter’s suggestions are appreciated but are beyond the scope of the proposed use of Method 320 as an alternative method. These suggestions will be retained and will be considered in the next methods update package.

Method 201A

10. Comment : Several commenters had questions about the isokinetic requirements in Methods 201A. We understand that

the EPA intends to reduce the number of allowable traverse point isokinetic values outside of the 80 to 120 percent range from five to two. One commenter recommended that, instead of reducing the number of allowable traverse point values outside the acceptable range from five to two
, the

EPA should reduce the number of traverse points above 120 percent to two and place no restrictions on the number of10

trav erse points below 80 percent . Traverse points below 80 percent introduce a bias to higher

- than

- true emissions. The

commenter felt s ources should be allowed to accept this
bias and not incur the cost of another test run. This proposed alternative approach t hat allows for additional isokinetic values less than 80 percent would simplify testing, especially for sources operating near ambient temperature where the allowable range in flow rates needed
to achieve the cut sizes for both the PM 10 and PM 2.5 cyclones is very small. It was believed to be very difficult to satisfy both the cyclone cut size requirements and the isokinetic requirements for low temperature sources. ( 0015, 0032, 0033, 0037)

Response : We believe the commenter has misinterpreted the requirements for isokinetic flow in Method 201A. The criteria are not changed from the version of Method 201A published in 1990

. The intent of this section in the method is to allow more than two point s outsi de the range when
more than 12 traverse points are sampled. The EPA disagrees with the commenters request to degrade the sampling quality if the source is the one that is disadvantaged. The intent

of our test methods is to obtain emissions measurements of

known accura cy and prec ision . If the stack tester believes that poor quality is acceptable if it results in a high bias, then they should justify this in their test plan description of the data quality objectives, date quality
indicators and the assessment of the use of the collected test data. It is then up to the regulatory authority to decide whether to accept the test for compliance determination or require that the test be conducted again.

11. Comment: A commenter noted that Section 7.2.1 allows 0.0001% (1 ppmw) residue in the acetone blank, but then later says this is the same as 0.1 mg/100 ml. It is not. It should be 0.1 mg/100 g. 1 ppmw would be equal 0.079 mg/100

ml. This same error can be found in Method 202 Section
7.2.1 . Similarly, M ethod 202, Section 7.2.2 for the hexane blank residue should be in the units mg/g and not mg/ml. 1.0 ppmw would be 0.065 mg/100 ml at 1 ppmw for hexane.

M ethod 202, Section 7.1.3 also has the same unit confusion

fo r the water blank, but since the specific gravity is 1, it works out to be the same value. (0021)

Response : The EPA acknowledges the error and has made the appropriate corrections in the method.11

12. Comment : Section 11.2.1 implies that when the temperature of the exhaust gas is not greater than 85 o F , then the procedures in M ethod 17 are sufficient for quantifying condensable PM. However, a note in the section for filter analysis (Method 5 Section 11.2.4) allows the filter and
wash solution to be heated above 85 o F. A commenter asked

that the temperature requirement for condensable PM filters
should be clarified. They suggested changing the note in
Section 11. 2 .1 to read “I n

- stack filter samples collected

at 30°C (85°F) may include both filterable insoluble particulate and condensable particulate. For these samples
, the nozzle and front half wash and filter may not be heated above 30°C (85°F). They should be desiccated then weighed, but not extracted since insoluble particulate will not be
recovered from the extraction. ” (0022)

Response : The commenter is correct that Method 17 filter analysis refers to Method 5 Section 8.2 and there is confusion about applying the subsequent sections of Method 5, (specifically the alternative offered in Section 11.2.4 of Method 5). We have adopted the suggested change (with minor revisions).

13. Comment : One commenter questioned the proposed requirement

to c onduct the preliminary traverse as close as possible to the anticipated testing time on sources that are subject to

hour

- by

- hour gas flow rate variations of approximately ± 20 percent and/or gas temperature variations of approximately ± 10°C (± 18°F). The commenter noted that Method 201A requires calculation of new delta Δ H values for points where temperatures are 28°C (50°F) above the average. It thus appears that the proposed revision would inadvertently “correct” the wrong temperature. The commenter recommended the following language: “Conduct the preliminary traverse

a s close as possible to the anticipated testing time on sources that are subject to hour

- by

- hour gas flow rate variations of approximately ± 20 percent and/or gas temperature variations of approximately ± 28°C (± 50°F).”
(0035)

Response : We agree with the commenter that Section 8.7 of Method 201A requires use of the appropriate ΔH when the
stack temperatures vary by more than 28 C (50 F). W e have
revise d the text in Section 8.3.4.1 to be consistent and indicate that preliminary traverse is conducted as close as possible to the anticipated testing time on sources that are subject to hour

- by

- hour gas flow rate variations of12

approximately 20 percent and/or gas temperature variations
of approximately 28 C ( 50 F).

14. Comment : Two commenters recommend ed that the EPA make a change to the Method 201A description that is not listed in the January 9, 2012
, Federal Register . The particle size

efficiency curves for the PM 10 and PM 2.5 cyclones should be presented as an additional figure. This information will allow developers of future methods or sampling equipment to compare the performance of different cyclones with the specified cyclones in Method 201A. (0037 , 0033 )

Response : We r ecognize that technical information requested by this commenter would help equipment manufacturers develop alternative equipment that meets the method specification. However this information is not necessary to implement the method correctly. Therefore, we plan to provide this additional technical reference on our website as a frequently asked question.

15. Comment : A comment er objected to the flagging of data not meeting the constant weight requirement and reporting these

data as a minimum value . This was believe d to be acceptable
for emission estimates but unacceptable for compliance
demonstration. For compliance demonstrations, the method should not require the reporting of values that are below the detection limit of the methodology. (0029 , 0032 )

Respon se : We disagree with the commenter because of their
misunderst anding of the method requirements. This issue is not about minimum detection limits as indicated by the commenter. The tester should have developed data quality objectives that incorporate d their capabilities for measuring a mass that was quantifiable and comparing this capability limit with the applicable limit for the source. The tester would then establish a minimum sample volume to meet quantifiable limits at the standard level. The

resu lting sample duration to meet the minimum sample volume would insure that they would have a mass above their minimum mass that would demonstrate compliance.

Rather
, the issue addressed in the method involves how to

handle measurable mass when the constant weight criteria

cannot be met
, as may be the case with hydroscopic particulate matter. If the case arises where the sample gains weight while it is being weighed and the constant weight criteria cannot be met
, then reporting the final13

weight with a data q uality flag provides an opportunity for the regulatory authority and the facility to understand

that there may be a quality issue with the data related to a compliance demonstration that needs to be evaluated.

16. Comment : A commenter notes that in the formula for “Sampling Rate Using Only PM 2.5 Cyclone” in Eq. 8
, the constant “0.060639” is off by a factor of 10 which
increas es the estimated Q s used for the pretest determinations. The formula found in “Application Guide for

Measurement of PM 2.5 at Stationary Sources ” (Eq. 5B

- 28) uses “6.0639 x 10 - 3 ” and gives a better estimation of the Q s for use in pretest determinations. (0024)

Response : We acknowledge and thank the commenter for this observation and will correct equation 8 in Method 201A

.

Method 202

17. Comment : Two commenter s though t the revisions to the nitrogen purging procedure were unclear. One noted that the revised language conflicted with the current language for impinger configurations. The other commenter felt the
revisions could lead to inadvertent errors. They

recommended that the revised text be clarified to indicate that the long stem impinger should not be the first impinger after the cooling coil during the test run. It should be clearly noted that the long stem impinge r is used only during the purging step. Sample gas contact with the condensed water in this impinger would contribute to
increased formation of artifact sulfates and other oxidized compounds formed from dissolved gases. ( 0026, 0037, 0033 )

Response : T he commenter s are correct that the empty impinger(s) are part of the M ethod 202 condensable particulate collection equipment. The revision referred to
in this comment was re written to clarify the text in Section 8.5.3.1 regarding sample purging after the sample
is collected. This revision does not change the

co nfiguration, number
, or contents of the impingers used to collect samples. In Sectio n 8.5.3.1 of Method 202
, if one choose s to conduct a pressurized nitrogen purge on the complete Method 202 sampling train, they may simplify the purge process by quantitati vely transfer ring the water collected in the condenser and the water dropout impinger

in to the backup impinger as an alternative to replacing the

short stem with a short stem insert in the knockout impinger prior to purging the sampling train. In this case
,14

the water combined in the backup impinger must be measured

and the resulting volume or weight recorded to be included as part of the moisture collected during sampling as specified in Section 8.5.3.4. This simplification eliminates the need to purge the condenser and knockout impinger contents since they are quantitatively transferred to the backup impinger that is already equipped with a long stem impinger stem. We have reworded the revisions to clarify the intent.

18. Comment : A commenter notes that, although efforts have
been made to minimize SO 2 absorption in the Method 202 condensate, the potential for SO 2 bias still exists, especially when the gas being sampled has high moisture
content. In the commenter’s discussions with the EPA, it
was indicated that, if condensate is accumulating in the first impinger, then the tester can stop the test run, remove the condensate, continue on with the test (having performed all the required leak

- checks), and begin purging

the removed condensate. The commenter ask ed that the EPA add this option if it is indeed an acceptable means of dealing with condensate in the first impinger. (0032)

Response : The EPA recognizes and agrees with the need to minimize gas contact with the moisture collected in the

M ethod 202 knockout and backup impinger. Section 6.1.2 of the method puts no restriction on the size of the knockout impinger for this method. If high moisture condenses and accumulates to overwhelm the capacity of the knockout impinger or if sufficient moisture condenses in the backup impinger to rise above the impinger tip
, then the test run may be stopped or interrupted to take corrective action.

19. Comment : A commenter pointed out that the “<” sign shown in the temperature range of the water bath should be

remo ved. (0032)

Response : This correction has been made.

§60.8 Cyclonic Flow and Gas Stratification

20. Comment : Two commenters expressed concern for the stratification testing and cyclonic flow testing requirements proposed for the Part 60 General Provisions and Method 1. They felt the proposed changes would affect the needed sampling equipment, time to prepare and conduct the test program , and the associated costs. Such costs15

could include installing sampling platforms at cyclonic

free locations, modifying the stack and upstream control equipment to eliminate cyclonic flow at the existing sampling location, or use of an alignment approach to measure the emissions. Most sources have very few options for sampling alternative test locations. Depending on the scale of the equipment and the materials of construction required, it was believed these modifications could cost an additional $50,000 t o $250,000 more. Use of the alignment approach would increase the on

- site testing time by approximately 50 percent.

The commenters did not believe t he propos al preamble provided technical justification for the need to eliminate cyclonic flow in sources being tested for gaseous
emissions. Method 1 was believed to already include sufficient requirements for addressing cyclonic flow in obtaining the gas flow rate da ta needed to calculate mass
emissions based on the concentration data.

It was not clear whether methods with separate lab analyses

such as Method s 18 and Method 26 could practically follow the proposed requirement s

. O n

- site analyses on a point

- by

point b asis would be needed, and this would significantly increase the cost of the test program. A stack testing
consultant estimate d the cost per three run test could increase by approximately $1,000. One commenter desired t he proposed changes be handled separat ely from the other proposed test revisions

. Both commenters felt that c hanges to these requirements should be based on a cost impact analysis and non

- confidential, readily reviewable data demonstrating the need for this change. One commenter
recommended th e EPA withdraw the proposed change s from the present rulemaking until this is done. (0037 , 0033 )

Response : T he commenters are justified in requesting a separate rulemaking for the proposed stratification and cyclonic flow revisions. We have withdrawn these revisions
from the final rule and will address them in a separate subsequent rulemaking

.

21. Comment : The Gen eral Provisions include the requirement for evaluations of gas stratification and cyclonic flow with all compliance tests. This seems overly burdensome. Initial checks for both should be adequate as long as there are no modifications to the process. (0020 , 0032 )16

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

22. Comment : A comment er believed the narrative added to check for cyclonic flow and emission gas stratification was unclear and inconsistent with subsequent requirements in the section. They recommended we revise to the following language: “An owner/operator should take reasona ble steps to ensure that sampling locations are free of cyclonic flow and flue gas stratification. If other procedures are not specified in the applicable subpart to the regulations, use the appropriate procedures in Method 1 to check for cyclonic flow and Method 7E to evaluate emission gas stratification and selection of sampling points. " (0029
, 0032 )

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

23. Comment : Two commenters noted that Section 60.8(h), Method 1, and Method 7E all have instructions/guidance and changes relative to selection of sampling points. It is not clear which approach is to be implemented for any given situation and the descriptions proposed in Methods 1 and 7E differ in a critical fashion. For example, the proposed language in
Method 7E contains a caveat for low concentrations and temporally varying sources that is not contained in the Method 1 language. Additionally, the Method 1 la nguage for the alternative point selection for the stratification check contains an additional criterion for using the three points that is not present in either the old or proposed

Method 7E. One commenter recommend ed that requirements for the point selec tion criteria be streamlined and clarified in a single location, and that all other methods or specifications reference the chosen location ; failing that,

the commenter recommended that clarifying language be added to clearly indicate the stratification ap proach to be used.

It was also unclear as to how a stratification test, in the

case of a non

‐ instantaneous gaseous measurement, was to be performed. If, for example, only Method 26 was being performed to determine HCl concentration, a stratification

test u sing the pollutant would require a separate sample train located at each point of interest, and analysis then performed which would of course be time and cost prohibitive. (0015 , 0022 )17

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

24. Comment : A commenter believes that cyclonic flow is not an issue for gaseous pollutant measurements and that no special procedures should be required for those pollutants regardless of the leve l of cyclonic flow. (0032)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

25. Comment : A commenter objected to the proposed addition to 60.8(h) which requires each test location to be verified to be free of cyclonic flow. The commenter notes that some amount of yaw and pitch angle are almost always present in utility stacks or ducts. The new proposal fa ils to acknowledge that under applicable procedures, like the one in Method 1, some level of cyclonic flow is acceptable without the use of special procedures, and even where the degree of cyclonic flow is deemed unacceptable,
measurements can still be mad e using alternative methodologies. The commenter believed a requirement that sources be free of cyclonic flow would warrant a reproposal discussing and quantifying the impact of the change on existing sources to Part 60. (0032)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

26. Comment : A commenter suggested that current 60.8(e)(1)(ii)
be revised to say “the owner/operator must attempt to provide...” rather than “the owner/operator shall provide” a stack or duct free of cyclonic flow during performance

tests. The commenter suggested alternative language for revising 60.8 th at would be clearer than the p roposed language and would list alternative procedures for testing when cyclonic flow was deemed significant enough to affect measurements. The language would also note that stratification testing need only be performed one time at the source if no physica l changes have been made that would alter stratification patterns. (0032)18

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

27. Comment : A commenter asked that the EPA address stratification requirements in a consistent manner. There are currently stratification testing requirements in Methods 1, 7E, and 30A, P erformance S pecification 2, and Appendix A of Part 75, all with their own nuances. (0029)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

28. Comment : A commenter encouraged the EPA to develop a

stand

- alone stratification method. Currently, there are stratification testing requirements in Methods 1, 7E, 30A,

P erformance S pecification 2
, and Part 75, all with their

won nuances.

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

29. Comment : A comment er cautioned the EPA not to use 12 points as a “default” number of traverse points for stratification tests. In many cases, a larger or smaller number of points need to be used in order to collect a representative sample.

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

30. Comment : A commenter pointed out that Method 1 does not specify the frequency of stratification testing and cyclonic flow determination (i.e. one

- time test, before each test event, etc. ). (0032)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

31. Comment : A question was asked relative to the proposal’s acknowledgement that a stratification test may not be meaningful at sources with temporally variable or low
emissions. The commenter asked that the EPA give a method19

of demonstrating temporal variation and id entify the concentration that would qualify a facility as a low

emission source and exempted from the stratification test. For temporal variation, it was suggested that a reference probe could be used to demonstrate that the process variability at an indiv idual point is consistently varying by more than 10 percent over a specified period of time (e.g., every 10 minutes). At sources where concentrations are low, diluent measurements could be used instead for the stratification test. (0032)

Response : See th e response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

§60.8 Method 205

32. Comment : A commenter supported the allowance to use Method 205 for field instrument calibration. However, it was supported only for methods where protocol gases are not readily available. The commenter acknowledged that calibration gas dilution systems may be necessary for some

reference me thods (e.g., those for mercury or HCl), but felt the added potential sources of error associated with these dilution systems should not allow their use for most common methods (e.g., Methods 3A, 6C, 7E, 10, 20, and 25). (0032)

Response : Method 205 was wr itten with tight performance
criteria to minimize sources of error. We believe the
benefit of reducing the number of gas cylinders necessary for a test is worth allowing Method 205 as a ca libration option.

§ 6 0.8 Audit Samples

33. Comment : A commenter believes Methods 30A and 30B should
be added to the list of methods for which audit samples are not required to validate performance test results

. Method 30A should be exempted because it is an
instrumental method. The final rule language for adopting

the audit sample provisions was cited as stating that it is necessary to require audit samples for those test methods that use instruments to measure pollutants in stack gas samples taken directly from an emission source because they already have sufficient ca libration and20

quality assurance requirements that would make an additional audit sample redundant.

Method 30B should be exempted from the audit requirement because it already contains measures sufficient to verify data acceptability. The commenter noted the requirement

that l aboratories demonstrate acceptable recovery from the chosen sorbent media through a bias test of spiked

sorbents , use of p aired trains to show precision and verify data acceptance, and field recovery tests to verify the sampling and a nalytical approach.

Response : We agree with the commenter and will add Methods 30A and 30B to the list of methods not requiring audit samples.

§ 60.13

34. Comment : A commenter recommended that the first sentence in the proposed clarification of 60.13(d)( 1) be further clarified by revising the phrase “at least once daily” to “at least once each operating day.” (0029 , 0032 )

Response : The recommended revision has been made.

35. Comment : For 60.13(h)(1), a commenter supported allowing
6

- minute averages to be based on fewer than 36 equally

spaced data points as proposed. Requiring the use of 36 equally spaced data points would result in invalid 6

- minute averages during each calibration and maintenance period. (0032)

Response : No response is necessary.

Subpart Db

36. Comment: A commenter supported the EPA ’s proposed change to Part 60, Subpart Db regarding the use of calibration
dilution systems as allowed by Method 205 of 40 CFR Part 51, Appendix M. This change increases the flexibility for conducting test programs and potentially reduces the safety hazards inherently involved in handling and transporting compressed gas cylinders. The commenter also supported the proposed allowance to use Method 320 for SO 2 and NO
x monitoring. This proposed change also provides increased test program flexibility. (0037 , 0033 )21

Response : No response is necessary.

Subp art JJJJ

37. Comment : A commenter objected to Method 320 being allowed for determining total VOC’s in Subpart JJJJ because its

results as the method is written are not comparable with

those from Method 25A. I f Method 320 remains as an alternative to Method 25A, adequate testing procedures
should be in cluded to ensure that the data generated from both methods are comparable. This should include a list of compounds that must be included in the sample analysis and procedures for determining detection limits. The option for using propane response factors s hould be removed. If Method 320 is used for determining VOC concentrations, the results should be reported as actual VOC’s and not as propane since there is no valid way to determine a theoretical propane response factor. (0020)

Response : The commenters r equest is beyond the scope of this rulemaking since we are not proposing to add Method 320 to Subpart JJJJ. This comment will be evaluated for consideration in the future methods update rule.

Engines Testing

38. Comment : A commenter noted that in removing Methods 1/1A from Subpart JJJJ in favor of sampling from the exhaust centroid, the mass based allowable option would still require Methods 1/1A for determining the number of sample points for measuring flow. Regarding flo w measurements, Methods 2 and 19 are listed as options but Method 2C should be added to this list. Regarding Method 19, this method is problematic because it would require fuel monitoring to determine the stack flow, and the regulation does not specify acc uracy requirements for fuel monitors. Similarly,

for NSPS

– Subpart IIII, removing Methods 1/1A requirements in determining the number of sample points for gaseous parameters does not take into account the same issues above for sample location and flow mea surements because this regulation also requires determining particulate compliance using Method 5, which in turn requires Methods 1/1A. (0016)

Response : The requirement for use of Method 1/1A for determination of sampling points will be removed for NO
x and CO measurement only. Method 1 or 1A will still be required22

for flow rate and particulate traverse point determination. Since Method 2C is the appropriate method for determining flow in small stacks, it will be added as an option to
Method 2.

39. Comment : T hree commenter s agree d with the proposal to eliminate the requirement to use Methods 1 or 1A for sample point selection in Subparts IIII and JJJJ and instead to allow the use of single point sampling at a centroid location. (0025 , 0033, 0037 )

Response : As explained in more detail in response to

Comment 41 below , the requirement to use Method 1 or 1A for sample point selection for gaseous pollutants/diluents has

been removed from Subparts IIII and JJJJ and single point sampling at a centroid location w ill be allowed for ducts
six inches or less in diameter

. Ducts measuring more that
six inches in diameter will need to be sampled at more than one point or tested for stratification.

40. Comment : A commenter noted that some requirements for Method 1 and 1A remain in Table 7 of Subpart IIII. These references to Methods 1 and 1A should be removed. ( 0033, 0037)

Response : Table 7 of Subpart IIII will be clarified to require Method 1 or 1A only for PM determination.

41. Comment : In Subpart IIII, Table 7 applies to compression ignition engines with a displacement of greater than or equal to 30 liters per cylinder. A commenter believed t his type of stationary engine should be equipped with sampling ports and have a stack d iameter sufficient for stratification checks. In addition, since engine manufacturers of such large units typically use catalytic controls to comply with the large engine NSPS standards, there is an additional contribution to gaseous emission
stratificatio n from control variation across the catalyst bed outlet. It is unlikely such a unit would have a stack diameter of less than twelve inches. Therefore, the

commenter recommends that the EPA not remove the requirement to use Method 1 or 1A for Subpart IIII e ngines. For NSPS Subpart JJJJ and NESHAPS Subpart ZZZZ, the

commenter concurs that for very small diesel and spark ignition engines, a centroidal approach could be warranted.
However, the commenter r ecommend ed that for an engine with
a functional stack dia meter of four inches or greater, it23

is reasonable and appropriate to retain a requirement to

use Method 1 or 1 A to check for stratification. (0034)

Response : The commenter makes two important points, first that stratification could potentially be introduced by catalytic controls and, second, that there is likely a significant population of internal combustion engines subject to at least one of the three subparts (Subparts IIII and JJJJ in Part 60 and Subpart ZZZZ in Part 63) that

have exhaust stack s greater than 12 inches in diameter
, which could reasonably be sampled at multiple points. Based on these considerations, we refined the approach for sampling port location/sample point selection for gaseous pollutants/diluents to be consistent across the three subparts that require performance testing of internal combustion engines to (1) allow single point sampling of the smallest ducts, (2) allow simplified three

- point sampling of the mid

- sized ducts, and (3) require a more
extensive traverse or stratif ication testing of the largest ducts that do not meet the minimum Method 1 port location criteria. More specifically, the final rule will allow ducts less than or equal to six inches in diameter to be sampled at a single point at the centroid of the duct. Ducts greater than six but less than 12 inches in diameter will need to be sampled at three specified traverse points unless they have been demonstrated to be unstratified according to Method 7E. For ducts equal to or greater than 12 inches in diameter, if the sampling port location meets
the minimum Method 1 criterion for distance from disturbances (such as catalyst beds), they may be sampled at three points; the two stack diameter distance downstream from the nearest disturbance will provide for gas mixin g and, coupled with a three

- point traverse, yield a representative sample. If they don’t meet the Method 1 criterion for distance from disturbances, ducts equal to or greater than 12 inches in diameter will be subject to stratification testing for determin ation of sampling points.

M ethod 1

42. Comment : The revision to Method 1 would state "The test for the presence or absence of cyclonic flow would be required for all tests instead of recommended at sites suspected of having cyclonic flow." Commenters asked if cyclonic flow checks are now required on rectangular stacks? (0011 , 0032 )24

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

43. Comment : The requirement to perform a cyclonic flow check for every testing event seems overly burdensome. An initial check for cyclonic flow during the initial performance test should be adequate, unless modifications are made to the process that would affect the gas flow characteristics of the stack gases. Documentation should be available on site during subsequent testing. (0035)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.

44. Comment : A commenter asked that Section 11.2.2, which currently addresses non

- particulate velocity traverses
, not
be revised to address non

- particulate velocity gaseous traverses. The commenter noted that gaseous traverses are not required for non

- isokinetic volumetric flow

mea surements, nor can the number of points for a velocity traverse be determined by a gaseous stratification test. Gaseous concentrations are impacted by stratification ( i.e., variations of concentration across the duct), while velocity me asurements are affected by cyclonic or turbulent flow). The commenter recommended the EPA include in the proposed new Gaseous Traverse section a provision for performance testing similar to Method 7E, Section 8.1.1

such as: For performance testing of conti nuous emission monitoring systems, follow the sampling site selection and traverse point layout procedures described in the appropriate performance specification or applicable regulation (e.g., Performance Specification 2 in appendix B to this part). In ad dition, the alternate criteria for gaseous traverse point concentration ( i.e., +/

- 0.5 ppm and +/

- 1.0 ppm) must include the alternate criteria for non

ppm diluent concentrations for oxygen and carbon dioxide from Method 3A (+/

- 0.5 percent and 0.3 percent ). Oxygen and carbon dioxide are ordinarily referenced in percent. (0035)

Response : See the response to Comment 21. Cyclonic flow and gas stratification will be addressed in a subsequent rulemaking.25

45. Comment : Commenters noted that in t he captions for Figure s
1

‐ 1 and 1

‐ 2
, the words upstream and downstream appear to be reversed. The distance from the sampling point upstream to the flow disturbance should be Distance B, and the distance from the sampling point downstream to the flow disturbance should be Distance A. (0015 , 0 035 )

Response : The commenters are correct, and the recommended
correction has been made.

Method 2

46. Comment : A commenter notes that i n the Section 12.1

n omenclature
, the EPA proposes correcting the variable

T s(abavg) , while equations 2

- 7 and 2

- 8 of §12.6 are not proposed to be updated. The EPA should update the equations substituting T s(abavg) for T s(abs) . (0035)

Response : We have updated the equations as well as the nomenclature as the commenter requested.

Method 3C

47. Comment : A commenter offered an a lternate calibration method consisting of triplicate analyses of an initial three or four part calibration extending through the applicable range of components similar to that of Method 25

and Method 25C. The average respo nse of each level of calibration is used to develop a linear calibration curve. A daily calibration analysis is performed in at least duplicate before the analysis of samples the average of which is compared to the initial calibration and accepted
if the r esponse factor for each component is within 20 percent of the initial calibration value, thus creating a continuing calibration curve. A second daily calibration is performed following the analysis of a set of samples or within 24 hours, whichever is short er, to determine analytical drift. If the post analysis calibration is
within five percent of the initial daily calibration
, the analyses are acceptable. (0005)

Response : This suggested calibration procedure is a good
one and is already al lowed under current Method 3C. No
method revision is needed.26

Method 4

48. Comment : A commenter commended the EPA for allowing F

factors to determine moisture in Method 4 but pointed out

the following issues with the way the procedure is written.

1. I n the equation for B F , the value for “W” is used in two places; however, there is not an explanation or equation for determining “W”. If “W” is a calculated value, an equation for calculating it should be included. If it is not calculated, then information should be prov ided for determining the value of “W”.

2. RH% is included in the nomenclature but is not used in any equation. If the RH% is to be used for calculating B Ws , then it should be added to the appropriate equation.
3

. The term “T” usually indicates absolute t emperature . Is
this correct in this case?

4

. The equation for calculating B A includes the value “T”. According to the nomenclature, “T” can be expressed in 0 F or

0 C. The value calculated for B A will be different depending on what units are used for ambient temperature. They are not interchangeable without changing the constants in the equation. It can’t be 0 F and 0 C.
5

. P bar is included in the nomenclature but is not shown in any of the equatio ns. If the value for PB is intended to be

used to calculate B W s , then it should be included in the appropriate equation. ( 0020)

Response : The term W is defined as the percent free water by weight. The term RH% was inadvertently left out of the equation for B A as a printing error. The units of the term T

are in oF . The alternate units of oC have been deleted

. The

term P bar is used in the calculation of B A and was inadvertently left out of the equation in the proposed rule due to a printing error.

49. Commen t : Two commenters supported the proposed changes in

M ethod 4 to allow methods other than Method 4 to determine the moisture content of a gas stream. One commenter noted

the missing term (% RH/100P bar ) in the B A calculation in the proposed notice

. A n incorrect placement of the minus sign after the parenthesis instead of before it in the exponent of the equation was also brought to our attention. ( 0033, 0037)27

Response : The missing term in the proposed notice is an inadvertent printing error. The placing of the minus sign

has been corrected as noted.

Method 5

50. Comment : Method 5 states that “mention of stopcock grease

for air

‐ tight impinger seals would be deleted since it is

outdated and not often used”. A commenter noted that his firm, as well as others, routinely use stopcock grease to seal the impingers when performing Method 5 tests. The newer style impingers with O

‐ rings can be used when required for certain types of tests where analysis of the impinger liquid is performed. However, it was m uch easier for the

commenter to use the standard ball and socket when a variety of impingers of slightly varying heights (as a result of purchases from various sources and numerous repairs over the years) are used in a particulate

- only

test. The ball with O

‐ ring combination does not work well at all if the impinger heights vary substantially. The

commenter asked that we leave the reference t o stopcock grease in the method.

Response : We disagree with the reasons from the comment e r to not support the remova l of stopcock grease from Method

5.

51. Comment : A revision to Method 5 states “the use of a Teflon filter holder would be allowed without having to obtain the Administrator’s approval first”. It was unclear

to a commenter whether the Teflon refers to the actual filter holder or the filter support or both. They noted

that t he use of a Teflon filter support should definitely be allowed without having to obtain the Administrator’s approval first. They felt Method 8 should also includ e a statement that the use of a Teflon filter support as well as a Teflon probe liner would be allowed, within certain temperature guidelines, without having to obtain the Administrator’s approval first. The Teflon filter support can be much more thoroughl y and easily cleaned than the glass frit. Florida DEP has previously provided guidance allowing the use of the Teflon liners within certain temperature guidelines (less than 350 0 F ) based upon
discussions with the EPA’s Emission Measurement Center. (0009)28

Response : We will clarify the language to refer to the filter holder support or frit only. We appreciate the additional comment for support of the use of Teflon liners in Method 5, but it is outside the scope of the propos ed

rule . We will consider the change in the next method s update package.

52. Comment : During a February 7, 2012
, w ebinar presented by

the EPA, it was stated that Method 5 would be updated to indicate that negative filter catches would count as "zero" in determining the sample catch. Howe ver, this is not reflected in the proposal. It should be, and not just for Method 5, but for all methods that include filter catches. Negative filter catches would be an indication of not properly preparing the filters prior to sampling, as specified in th e methods. Excessive negative catches could be an indication of improper/incomplete sample recovery and/or lost samples. A maximum negative catch value should be listed whereby the data would have to be flagged as qualified/compromised in the test report. (0016)

Response : We appreciate the comment for a prescriptive handling procedure of negative gravimetric catches, but it would be outside the scope of the proposal. We will consider the change in the next method update package.

53. Comment : T he acetone maximum blank residue allowance currently in Method 5 is less restrictive by a factor of 10

than the Method 201A and Method 202 allowances. Given that Method 5 is being used to measure similar low emission levels as Methods 201A/202, the blank r esidue allowances in Method 5 should be the same as those in Methods 201A/202. (0016)

Response : We appreciate the comment for changing the acetone blank allowance, but it would be outside the scope of the proposal. We will consider the change in the next method update package.

54. Comment : For Method 5, Section 6.1.1.5, the use of Teflon
filter holders is being added. This change is supported as long as truly leak

- free Teflon holder assemblies are available. Additionally, the wording in this section of the docket refers to the entire holder being made of Teflon. It is my understanding the original proposal for this change was to allow for using the PTFE filter supporting “frit” developed by Thomas Thompson in 1987, intended originally29

for use with BIF method s, and Methods 23, 26A, 29, etc. (i.e.: a Teflon frit combined with the standard borosilicate glass inlet and outlet components). Since glass holders combined with the Teflon support frit is likely the most common filter holder configuration in use
with st ack testing currently, please consider including the necessary wording allowing the use of either alternative in a filter housing arrangement. (0031)

Response : We will clarify the language to refer to the filter holder support or ‘frit’ only.

55. Comment : For Method 5, Section 6.1.1.9, the current alternative test method using the Isostack metering system is proposed to be added within the method (instead of the original alternative test method). Since the original components of the Method 5 metering syst em go back at least 40 years, there seems to be strong support in the testing community for allowing modern, and potential ly more accurate, metering systems that can provide equivalent or better data quality. Will the E PA continue to initially
issue altern ate test methods as other metering systems become available and are approved for use? Or once performance data for an alternative meteri ng systems is provided, will the EPA simply issue acceptance or equivalency letter to the manufacturer for an alternative metering system, citing this modified section in Method 5? (0035)

Response : We are not finaliz ing the reference to the Isostack metering system

. We will continue to iss ue broadly applicable alternative method determinations or letters of assessment as to whether equipment meets intent of the

method to the manufacture r s.

56. Comment : One commenter was concerned that the EPA’s

allowance of the Isostack metering system if the flow rate calibration does not deviate by more than five percent while requiring a two percent stability for other acceptable systems. The commenter believed that specifically allow ing one manufacturer’s product, while

hold ing other s to a different standard, provides an unfair business advantage and prevents fair competition in the marketplace for future development. (0029 , 0032 )30

Response : We are not finaliz ing the modification to
Section 6.1.1.9 that references the Isostack mete ring
system.

57. Comment : In Section 7.1.3 of Method 5 regarding water
, the EPA proposes adding a specification for water if it will be used for other analyses. One commenter believed the EPA should change this section to refer to the water specifications contained in the applicable method for performance of the additional analyses. Another commenter
believed a maximum blank water residue of <0.001% is less restrictive by a factor of 10 to the residue allowance in
Method 202. (0016 , 0035 )

Response : We agree with the commenters and will revise the language to refer to the water specifications required by the applicable method for additional analysis

.

58. Comment : A single

- point post calibration procedure of temperature sensors was proposed for Section 10.4 ( Probe
Heater Calibration ). A commenter thought the procedure should be placed in Section 10.5 because it deals with temperature sensors, rather than in Section 10.4. (0035)

Response : We have made the appropriate change in the final

rule.

59. Comment : A commenter support ed the proposal of alternative

method Alt

- 009 to Section 16.3 for the field calibration

check of the metering system. The commenter did not believe
this alternative should require the second leak

- check procedure in Section 16.3.1.2 and described in Section
10.3.1.1. The leak

- check described in Section 10.3.1.1 is intended for systems with diaphragm pumps, and requires a wet test meter to accomplish. Sampling systems may use other type of pumps, such as a vane pump, that do not exhibit the same problem with the detection of leaks

between the meter and the pump. In addition, this leak test was thought to defeat the purpose of a field calibration as it requires a wet test meter which is not typically
available in the field. It was recommended that the method specify that the leak

- check described in Section 10.3.1.1 is only required for diaphragm pumps. Additionally, the following alternative metering system and pump leak check procedure was recommended for the final rule:

“ First disconnect the static

- side manometer tubing at the
orifice. Then close

- off the orifice outlet and the orifice31

static

- side port using two small rubber stoppers. Apply and hold a positive pressure at the meter inlet. If the pressure as displayed at the incline manometer does not drop, then the metering system and pump can be considered

leak

- free. ” (0035)

Response : We agree with the commenter and will revise the language in the final rule to use the procedures in 8.4.1.

60. Comment : A commenter recommended the EPA clarify the proposed acetone blank collection procedures stated in Section 8.7.5. As written, it is possible to interpret the proposed change as requiring two separate acetone blanks : the acetone storage bottle and the acetone

- containi ng wash

bottle

. The commenter felt the change w ould increase the laboratory costs associated with Method 5 i f it is the EPA’s intention to require two acetone blanks . The
commenter believed the increased cost should be considered by the EPA when determinin g if this requirement provides any additional benefit to the testing process. ( 0033, 0037)

Response : We will clarify the language to note that only

one re a gent acetone blank is required from the storage bottle used in the cleanup.

61. Comment : In the revision to Section 6.1.1.7 to recheck the temperature sensor at one point after each test, a commenter recommended that each test be defined as a single testing event. This would allo w for testing to be completed on more than one unit during a single mobi lization. (0029
, 0032 )

Response : We disagree with the recommendation due to the lack of support ing data for the allowance.

62. Comment : A commenter recommended we clarify which temperature sensor must be in “direct contact with the sample gas.” Should it be the probe or filter box temperature? It was noted that the filter temperature sensor is generally not in direct contact with the sample gas, but rather is located within the heated filter box. A misapplication of the specification would require signifi cant modifications to existing equipment and make the majority of filter holders in service today obsolete. (0029 , 032 )32

Response : We disagree with the commenter. The EPA revised

Method 5 on October 17 , 2000
, ( 65 FR 61744) to require the measurement of the filtration temperature with a temperature measurement involving direct contact of the sample gas after the filter. We are revising the language to clarify that requirement and provide for an allowance

for a gl ass, teflon or SS thermowell a s well as for a second thermocouple for the control of the heated filter box temperature.

Method 5E

63. Comment : A commenter supported the allowance to use the

Tekmar

- Dohrmann analyzers using the single injection technique as an alternative to the Rosem o nt Model 2100A. The commenter noted that there are no known problems with this new alternative, and it provides greater flexibility in conducting tests in a variety of different circumstances and conditions and with multiple testing firms.

Response : No response is necessary.

Method 6C

64. Comment : Two commenter s believe d the proposed interference analyses procedures as written for Method 6C would be
difficult to conduct. It was not clear why the interference

data would be relevant if the gas stream is stratified with oxygen and/or carbon dioxide concentrations varying by substantially more than 1 percent volume. Th e modifi cation
did n o t appear to be practical for all sources. Th e requirement to compile interference data for concentrations

of O 2 and CO 2 within 1 percent volume of the stack concentration should be modified to require interference data applicable to be within 1 percent volume of the averages of the O 2 and CO 2 concen trations in the stack gas stream. ( 0033, 0037)

Response : For years, Method 6C has contained this requirement and there has been little protest from testers or manufacturers. The provisions were deleted from Method
6C in 2010 when the instrumental source methods were updated because we believed the analyzer techn ology has advanced beyond the need for quenching correction. However, based on discussions with manufacturers and testers, the quenching effects of oxygen and carbon dioxide still present significant effects that should be corrected.33

At sources where it i s impractical to handle the interference through matching of calibration and sample matrices, other alternatives such as the use of nomographs

are allowed.

65. Comment : C ommenter s did no t think quenching poses a significant issue with extra ctive fluorescence system and suggested the quenching provisions be removed. They believed it unreasonable and expensive to maintain an adequate stockpile of calibration gases to satisfy the requirement that calibration gases be within 1 percent of

the absolute oxygen and ca rbon dioxide stack content. They believed the added provisions would reduce the incentive to use analyzers affected by quenching and would result in testing delays and unreasonable costs. The commenter felt

that , if required, the EPA should de velop a quenching check procedure specific to the type of source and that a single check per specific analyzer should be enough. (0029 , 0032 )

Response : See the response to Comment 6 4

.

Method 7E

66. Comment : A statement is being added to Method 7E noting that the stratification test is not required at sources with temporally varying emissions

. This was unclear to one
commenter who asked if the source's emissions are tempora rily varying why not wait and test when the emissions are stable? (0011)

Response : This statement has been dropped and is not in the final rule. We will evaluate means of determining stratification where emissions are temporally varying and
address them in a future rule.

67. Comment : Two commenters believed that instrument quenching

should be specifically addressed in Method 7E. Quenching has long been known to be a problem with both fluorescence and chemiluminescence based analyzers. This proposal

return s the necessary quality assurance to address quenching back into Method 6C
, but not in Method 7E. S ome
NO x analyzers are optimized to greatly minimize the quenching problem but all analyzers are not created equally

. One commenter believes t he analyzers that do not handle the problem well are largely flying under the radar

and causing emi ssions to be under reported. The commenter34

knew of at least one current chemiluminescence

- based analyzer where the manufacturer indicates special
calibration methods must be used to account for the effects of quenching if CO 2 concentrations exceed 0.5 perc ent

. Due to the inconsistent design of the analyzers, the commenters
believed Method 7E should include procedures to check the analyzers for the effects of quenching. These checks were

not felt to be need ed for every test but could be done at a
minimum aft er the analyzer has been repaired or modified or on another periodic basis

. The simple fix would be to require a periodic check at about 4 percent and 12 percent

CO 2 at a mid

- range concentration for each analyzer range which is commonly used. (0014 , 0018 )

Response : The commenters raise valid concerns that have

been addressed. Method 7E now requires a check for quenching prior to use of the analyzer and at two levels of

CO 2 after each repair
, modification , or other periodic
basis

.

68. Comment : A commenter felt t he inclusion of a Method 7E
stratification check in Method 1 was confusing since Method 1 is primarily used for velocity measurements . (0016)

Response : The proposed requirement that all tests be evaluated for gas stratification and cyclonic flow following Method 1 has not been included in the final rule. See the response to C omment 21

.

69. Comment : Two commenters asked that the language in Section

7.1.1 of Method 7E be amended. One commenter felt that

p ollutant emissions, especially carbon monoxide, could vary over a wide range during a test run. In this case
, if a single range analyzer is used with sufficient span to quantify peak emissions
, then the av erage concentration of the emissions may be less than 20 percent of the high level

gas. The commenter suggested we add “To the extent possible” to 7.1.1 so it reads: ... To the extent possible
, choose this high

- level concentration so that emission

measuremen ts will be within 20 to 100 percent of this
concentration. The other commenter asked that the sentence
be deleted since it could cause confusion and the measurement range and the exception for low

- level concentration are already addressed in Section 3.4. ( 0022
, 0035 )35

Response : The noted sentence has been dropped from Section 7.1.1 since the information is already addressed in Section

3.4.

70. Comment : A commenter expressed support for the requirement that system bias and calibration error checks be based on
the amount of time it takes for the measured concentration to increase to 95 percent or 0.5 ppm of the stable response and not necessarily of the certified concentration. This was believed to represent the actual response time of the system more accurately. (0032)

Response : No response is necessary.

71. Comment : A commenter felt t he proposed changes to section

8.2.5 of Method 7E w ould reduce the precision and accuracy of the response time determination. The change requires

that the response time be recorded after the concentration reading has reached 95 percent or within 0.5 ppm of a stable response for the gas instead of after reaching 95 percent of the certified gas concentration as in the

current method . This change was proposed to allow the

s ystem bias to be taken into account before the response time reading is recorded and to conform the section to
Section 8.2.6 . The commenter noted that this will require response time to be determined retrospectively because the value of the stable response cannot be known until well
after the time when 95 percent of the step change (upscale or downscale) was reached. D ata stored by a data logger

would have t o be examined, but data loggers typically store only one

- minute averages of data sampled during a given minute because of data storage limitations. Under the proposed revision, response time would not be determined with a precision better than to the neare st minute. System response to a step change is rapid for about the first 80 percent of the change, slow between 80 percent and 90 percent of the change, and even slower for the last 10 percent of the change, as response asymptotically approaches a stable v alue. Therefore, response time determined to the nearest minute under the proposed
revision could be biased high by up to one minute. This will increase sampling times without providing any benefit. In contrast, the current procedure for determining respon se time is both more accurate and more precise than the proposed revision. The analyzers are calibrated immediately before measuring response time, so responses to low

- level36

and to upscale gases should be very close to their
certified concentrations. There fore, 95 percent thresholds calculated from the upscale gas concentration should be very close to 95 percent of the final stable responses, and response time determined using those thresholds should be accurate. Furthermore, since the values of 95 p ercent (upscale) and 5 percent (downscale) of the certified high

level concentration are known before the response time test is started, the current procedure permits response time to be determined with a precision of up to the nearest second. The proposed revision would have been suit able decades ago when analog strip

- chart recorders were used, which permitted an accurate, precise determination of response time retrospectively from a paper chart. However, the proposed revision is poorly suited for use with modern data loggers, which ke ep a permanent electronic record of data, but which are generally restricted to storing one

- minute average data because of data storage limitations. The

commenter felt that Section 8.2.6 should be worded to conform to the existing wording in section 8.2.5. (0039)

Response : The revision to allow the response time determination to be recorded at less than 95 percent of the certified gas concentration should not be less accurate or precise than the current requirement. The revision does not
prevent using the 95 percent of gas concentration for the response time endpoint if so desired. The revision only gives relief to systems that need up to the 5 percent bias
limit to be able to meet the specification in a reasonable
timeframe. In most case s , the continuous instrumental readout should be sufficient for determining response time without having to consult the retroactive data. In systems
where this is not practicable , response times must be computed using minute

- averaged data.

Method 8

72. Comment : A commenter noted that the 100 ml aliquot from
Container 2 for SO 2 analysis in Section 11.2.2 is a typo and should be 10 ml. (0032)

Response : The commenter is correct. This typo has been

corrected.

Method 1037

73. Comment: Two commenters expressed their support of EPA’s proposed changes to allow for the use of sampling bags made
from materials other than Tedlar. ( 0033, 0037)

Response : No response is necessary.

Method 10A and 10B

74. Comment : A commenter asked that the use of canisters for sampling be allowed in Method s 10A and 10B as is the case
for the modification to Method 10

. (0005)

Response : The sampling and analysis procedure s in Method s 10A and 10B are designed specifically for using a Tedlar bag. The se procedures and equipment would have to be
modified to accommodate canisters. Canisters should be an acceptable alternative to bags in this case, however, redesigning the method to accommodate canisters is beyond the scope of this rulemaking. The u se of canisters will be

addressed in the next methods update rulemaking. In the meantime, you may request the use of canisters as an alternative method to Method s 10A and 10B through the alternative methods option allowed under 40 CFR 60.8(b)(3)

.

Method 11

75. Comment : Two commenters support ed the proposed changes to

Method 11. They noted that parties concerned about possible depletion of the absorbing solution can comply with the proposed requirements simply by adding an additional impinger. ( 0033, 0037)

Response : No response is nec essary.

Method 18

76. Comment : A commenter pointed out a typographical error i n Section 8.2.1.1.2 of Method 18 . The end of the probe should

be at the centroid of the stack or not closer to the side walls than 1 inch, not 1 meter (1 m). (0031)

Response : The commenter is correct and this typographical

error has been corrected

.

Method 2338

77. Comment : A commenter cited a number of exceptions made on

the EPA E mission Measurement Center website allowing Method

23 without the use of dichloromethane as a recovery

solvent. The commenter applaud ed the removal of this solvent, from both a safety and shipping perspective
, and

recommended we consider making this change in Method 23
itself. (0015)

Response : The commenter’s sugge stion is appreciated but is beyond the scope of the proposed revisions to Method 23. These suggestions will be retained and will be considered in the next methods update package.

78. Comment : Method 23 specifies, in S ection 4.2.3, that the
condenser coil be recovered in the same manner as the connecting line. A commenter’s understanding was that the connecting line soak is based on the nature of Teflon, and the possibility of cold

‐ spots in the heated line. The

commente r didn’t think t hese issues apply to the condenser. They recommend ed we clarify this intention for the
condenser rinse . (0015)

Response : The commenter’s suggestion is appreciated but is beyond the scope of the proposed revisions to Method 23.

These suggestions will be retained and will be considered in the next methods update package.

79. Comment : A commenter believed Method 23 should be modified

to address t he counting of Estimated Maximum Possible Concentrations (EMPCs) in determining total dioxins/f urans. They noted that, i n many cases, testers and labs count EMPCs as zero in determining totals. By EPA direction
, if

the so urce (facility) includes EMPCs in the total reported for dioxins/furans and is still in compliance with the emission limit, then t he results can be accepted. If the

s ource includes EMPCs in the total reported for dioxins/furans and is above the emission limit for total dioxins/furans, it may be because of a positive interference. However, the interference cannot be quantified and th i s interference will prevent the lab results from meeting the quality assurance requirements for identifying and quantifying their results. In this case, the only option would be for the laboratory to re

- analyze the sample if they archived a sample fraction, or repeat

the test. The re

- analysis would involve re

- cleaning the sample to remove the interfering substance

. (0016)39

Response : The commenter’s suggestion is appreciated but is beyond the scope of the proposed revisions to Method 23. These suggestions will be retained and will be considered in the next methods update package.

Method 24

80. Comment : A commenter recommend ed that 40 CFR 60.17 be further revised. The revision to Method 24 of Appendix A

- 7 references only ASTM Method D2369 and not the specific sections of the method (since the section numbers may change with periodic updates)

. H owever , entry (34) in paragraph 60.17 (Incorpo ration by Reference) restricts the

use of ASTM D2369 to the 81, 87, 90, 92, 93 and 95 specific
revisions

. The commenter strongly recommend ed that paragraph entry (34) of 60.17 also be revised to include the most current version of ASTM D2369, namely D2369

- 10e1. (0030)

Response : Section 6.2 of Method 24 lists the versions of ASTM Method D2369 that are acceptable in Method 24. This listing is the same as in 60.17 versions. Subsequent
references to D2369 in the Method 24 instructions do not include the year listings.

Method 25

81. Comment : One commenter asked t hat trap capillary lines be

allowed in conjunction with in

- stack filters in inlet sampling to control devices during destruction and removal efficiency ( DRE ) testing only where the temperatures of the inlet sampling location exceed approximately 121 o C. This

would prevent the negative bias which can occur due to the sample gas stream being cooled, which in turn can cause loss of organic compounds in the probe and filter assemblies. As this is the inlet to a control device, the possible particulate matt er would still be a portion of the loading and as such should be included in the sample. Sources with naptha

- based solvents, for example could suffer significant losses of organic loading due to the cooler glass fiber filter. This would not be applicable t o OUTLET monitoring due to the overlap between organic and particulate measurements causing a potential double counting. (0005)

Response : We disagree with the commenter that this is a broadly applicable change that needs to be made to Method40

25. Since th e comment refers only to destruction and removal efficiency (DRE) and only to inlet measurements at

these tests
, we recommend the commenter pursue a site specific alternative method approval process described on

the EPA’s website at http://www.epa.gov/ttn/ emc/guidlnd/gd

022r3.pdf

.

Method 25C

82. Comment : A commenter recommended the proposed nitrogen
correction for dilution be added to Method 3C instead of
Method 25

- C because the raw data for Method 3C may not be available for the Method 25C analysis

. This commenter and

another recommended the dilution correction include the optional correction for oxygen for those cases where the sample had an oxygen concentration less than five percent
but a nitrogen concentration that was proportionally higher

and would c reate a positive bias. (0013, 0019)

Response : We agree that the nitrogen correction for
dilution would be more useful in Method 3C than Method 25C,
and this has been done. We’ve noted that the equation may be used for oxygen correction by substituting values for oxygen in place of nitrogen.

Method 26

83. Comment : A commenter pointed out t he difference in temperature s for the probe in the proposed change to
Section 6.1.1 ( 248 ± 25°F ) and that of Method 26A (greater than 248°F). This is also counter to the revised Section 8.1.2 which also indicates a temperature of greater than 248°F. (0015)

Response : We have clarified the language in both Method 26
and Method 26A to be consi stent with maintaining the
temperature of the probe and filter between 120 and 134 C (248 and 273°F). Above this temperature range

, we have evidence for positive bias from ammonium salts. Below this temperature range , moisture condensation is a concern.

84. Comment : A comment er felt that i n Section 6.1.1
, the final sentence appears to be missing some language: “A

Teflon

‐ glass filter in a mat configuration should be installed in the gas stream, not the filter box, to remove particulate matter from the gas stream.” This sentence, as it stands, d id not appear to signal the intent of the41

change desired. According to the proposal preamble, the
intent was to indicate that the location of the thermocouple used to monitor the filter temperature should be in the ga s stream. (0015)

Response : The commenter is correct. The amended language was out of place and is not in the final rule.

85. Comment : Another commenter took exception to the proposed language for Section 6.1.1 . The commenter noted that a
Teflon filter or filter holder should not be installed in a high temperature gas stream and would be at odds with the rest of the method, including the test train schematic. The

commenter note d there is no benefit to doing s o because that is the purpose of the heated filter box. (0035)

Response : The proposed language has not been included in
the final rule.

86. Comment : A commenter asked if the new a lternative

p rocedure in Section 16 mean s Method 26A has to be

conducted isokinetically when used in place of Method 26, or is it allowable to sample proportionally (such as a fixed sampling rate of 0.75 CFM) at a single point as in Method 26 (i.e.: non

- isokinetically) when the stack gas dew point is low and there i s no chance of aerosol droplets

. They requested clarification of this section. (0031)

Response : Method 26A implemented as written has been designated equivalent to Method 26. Method 26A remains an
isokinetic method for initial and alternative applications unless specified otherwise in a specific regulation or

rule.

87. Comment : A commenter supported the pro posed revisions to
Method 26 but was concerned with the change in the thermocouple location requirement a nd believed t here were more economical and practical means to prevent inaccurate temperature data. Noted alternatives include d measuring the probe exit gas temperature in a dimple installed within 12 inches of the probe end and physically attaching a thermocouple in the filter holder. T hese approaches would

no t require the temperature probe to be in the gas stream nor would they incur the costs and small gains experienced by having the thermocouple in the gas stream. ( 0033, 0037)42

Response : The proposed amendment addressing the location of the temperature sensor was in error and is not in the
final rule.

Method 29

88. Comment : A commenter supported the allowance for cold vapor atomic fluorescence spectrometry ( CVAFS ) as an alternative to the atomic absorption spectrometry ( AA S) analysis because it reflects the various analysis techniques that are available to the regulated indus try. (0032)

Response : No response is necessary.

Method 30B

89. Comment : T hree commenters wanted the sorbent trap alternative breakthrough criteria being allowed for relative accuracy test audits ( RATAs ) to also apply to compliance tests. They noted the difficulty in meeting the 20 percent breakthrough limit for compliance samples when
concentrations are below 0.5 μ g/dscm

. (0029, 0032, 0035)

Response : The alternative breakthrough criteria being allowed for RATAs are provided in part to address the difficulty in meeting the breakthrough criteria when sampling for the shorter run times (e.g., 30 minutes) often used in conducted RATA test runs. We understand that it may still be difficult to meet the 20 percent breakthrough criteria at very low mercury emission levels even with one or more hour run times used in compliance testing and have therefore provided some additional flexibility (though not all requested by the commenters) tied to the emissions
limit level. An additional criterion will be added t o Table
9

- 1 as follows : " At mercury concentration levels at or below 30 percent of the Hg concentration that is equivalent

to applicable emissions limit, the breakthrough criterion
will now be < 50 percent of the section 1 Hg mass. " In addition, based on further consideration of these comments as well as information we have received independently from at least one state currently implementing both Method 30B and Performance Specification 12B in a mercury control program, we are also making a revision to the breakthrough
criteria in Performance Specification 12B to provide a similar flexibility at the extremely low concentrations43

currently being measured: " When mercury concentration level
is less than or equal to 0.5 μg/scm , the breakt hrough
criterion will now be < 10 percent of the section 1 Hg mass

rather than < 5 percent of the section 1 Hg mass and when the mercury concentration level is less than 10 percent of the emission standard, there will be no breakthrough
criterion. " This ch ange will not affect data quality and will prevent invalidation of valid data at low
concentrations.

90. Comment : The note to Section 8.2.4 cu r rently states: “for the purposes of re l ative accuracy testing of Hg monitoring systems under part 75 of this chapter and Performance Specification 12A in appendix B to this part, when the stack gas Hg concentration is expected to be very low (<0.5

μ g/dscm) you may estimate the Hg concentration at 0.5

μ g/dscm. ” A commenter recommended the reference to Part 75 be deleted as Hg is no longer addressed in Part 75. More importantly, they believed the Part 75 reference should be replaced with a reference to Appendix A, Subpart UUUUU of

Part 63. The rea son is that in the EPA’s final Mercury and Air Toxics (MATS) rule affecting electric generating units, all requirements for Hg monitoring systems are contained in Appendix A; the MATS rule contains no reference to

P erformance S pecification 12A. There is a similar reference
to Part 75 in the note to Section 8.2.6.2 of Method 30B that should also be deleted and replaced with a reference to Appendix A, Subpart UUUUU. (0032)

Response : The EPA agrees with the commenter that the reference to part 75 should be d eleted from the Notes in
Sections 8.2.4 and 8.2.6.2 of Method 30B. The EPA also agrees that it would be appropriate to replace the reference to part 75 with a reference to Appendix A of 40 CFR part 63, subpart UUUUU. The EPA notes that it would also be app ropriate to reference Performance Specification 12B in appendix B to part 60 in addition to Performance Specification 12A and has made all the above revisions to
the final rule.

91. Comment : In the preamble to the proposed rule, the EPA

states:

For compliance/emission testing, the specification in

Table 9

- 1 for sample analysis would be revised to require analytical results be within the valid calibration range down to a concentration of 0.0144

μg/m3. This will ensure that measurements at the low

levels being measured under recent rulemaking s are of known, acceptable, and consistent quality.

A commenter noted that an i nspection of Table 9

- 1 indicates

that the EPA failed to make this revision. The commenter
did not believe the EPA should unilaterally re vise the sample analysis specification in Table 9

- 1. Rather, the sample analysis specification should be linked to where the Hg measurement is being made relative to the applicable
emission limit. The commenter recommended that Table 9

- 1 be revised to requ ire analytical results be within the valid calibration range whenever the concentration is equal to or greater than 50 percent of the applicable emission limit. As an example, if the Hg emission limit were 0.8 μg/dscm and the measured flue gas concentrati on is 0.4 μ g/dscm, then the sample analysis would be required to fall within the valid calibration range of the analyzer. On the other hand, if the measured flue gas concentration were 0.2 μg/dscm relative to the 0.8 limit, there would be no justification for requiring additional sampling time and effort just to fall on the calibration curve. (0032)

Response : The EPA appreciates the commenter pointing out
that it was the a gency’s intent to include the proposed revision explained in the preamble as part of Table 9

- 1 and
notes that it was our intent to include the referenced
revision in Table 9

- 1. The EPA understands the commenter’s concern about having to sample for additional time just to ensure the sample results fall on the calibration curve
when the emi ssion levels measured are substantially below an emission limit. In response, in the final rule we have

made a two

- pronged revision to the proposed sample analysis criterion for compliance emission testing: (1) the general
criterion has been doubled to 0.0 2 μg/dscm

, and (2) an exception has been added to allow additional flexibility where the measured flue gas concentration is less than 30 percent of the concentration that is equivalent to the applicable emission limit. We made the cutoff at 30 percent

as opposed to 50 percent as suggested by the commenter to ensure data quality for a larger margin of compliance.

92. Comment : A commenter asked that we remove the referen ce to a mercury barometer from Section 10.4 to maintain consistency with the changes to Table 9

- 1. (0035)45

Response : The EPA agrees with the commenter and revised the language in section 10.4 of Method 30B to make it
consistent with that of Table 9

- 1.

PS

- 1

93. Comment : Two commenter s objected to the note being added to Section 3.5 stating “full scale” means “span
, ” and recommended it be dropped. One commenter felt this was misleading and inaccurate because “full scale” of any COMS is 100 percent. The new definition may also be misrepresented for other pollutant analyzers. The commenter noted rules that have spans that are set at one level while the range of the instrument is at a higher level. They
noted that this is also true for COMS where the COMS is spanned at a lower value (e.g. 40 or 60 percent) to improve the accuracy of the measurement near the opacity limit. (0029 , 0032 )

Response : We agree with the commenters and have not made
the amendment to Section 3.5.

94. Comment : A commenter was disappointed that the EPA did not correct the longstanding language problem in paragraphs 8.1(2)(i) and 8.1(2)(ii). As the EPA previously acknowledged in a response to the Frequently Asked Questions (FAQ) : “Paragraph 8.1(2)(i) should not limit the
COMS locations to the four and two diameter sites, but instead should defer to 8.1(2)(ii) for additional options. Paragraph 8.1(2)(ii) is clear that you can install a COMS
in a location that is not at least 4 duct diameters downstream and 2 duct diameters upstream of flow
disturbances as long as you meet the appropriate requirements in the table of 8.1(2)(ii) and the associated figure. The commenter thought EPA should at least include its FAQ language somewhere in Section 8.1. (0032)

Response : The commenter’s suggestions are appreciat ed but are beyond the scope of the final rulemaking since they were not included in the proposal. These suggestions will
be retained and will be considered in the next methods update package.

PS

- 3

95. Comment : A commenter supported the proposed amendment to Section 12.2 to include a relative accuracy percentage46

criterion in addition to the mean difference criterion. (0029 , 0032 )

Response : No response is necessary.

PS

- 4 and 4A

96. Comment : A commenter asked that it be made clear when

P erformance Specification 4 (PS

- 4) versus Performance Specification 4A (PS

- 4A) should be used. It should state
that PS

- 4 is for CEMS with span values of 1000 ppm, and PS

4A is primarily for CEMS with emission standards less than 200 ppm. Guidance was sought on which PS is appropriate in the range between 200 and 1,000 ppm. (0029 , 0032 )

Response : The choosing of a performance specification between the measurement ranges of 200 and 1,000 ppm should be assessed and established during rulemaking. In cases

wher e the applicable regulation is not clear, our recommendation is that either PS may be used and a specific span be chosen that is approximately twice the concentration of the emission standard or the average
emissions concentration. Intervals of concentrati on spikes
should also be considered.

PS

- 7

97. Comment : In Section 8.4.2.1, A commenter recommended that

the EPA not add the proposed statement that “ Each sample shall be taken at approximately 30

- minute intervals ” to
Section 8.4.2.1 for Methods 11, 15, and 16

. The commenter
believe d this would increase the duration and cost of the testing without improving the precision or the accuracy of the RATA results. (0035)

Response : We dis agree with the commenter since sampling strategy and reference method tests are already addressed
in referenced sections of P erformance Specification 2 (PS

2)

. Under PS

- 2, the 21

- minute minimum sampling time was chosen considering grab samplers and non

- instrumental samplers need time over the 30

- minute test interval to
switch out sampling systems.

PS

- 11

98. Comment : A commenter asked that a reas in P erformance Specification 11 (PS

- 11) that are currently not clear be47

addressed in this rule. Section 8.4.6(4)(i) states that “you must attempt to obtain the three different levels of PM mass concentration by varying process operating conditions, varying PM control device conditions, or by means of PM spiking.” Section 8.6(5) states “if you cannot
obtain three distinct levels of PM concentration, as described, you must perform correlation testing over the maximum range of concentrations that is practical for your

PM.” The commenter did not believe there were reasonable means for increasing PM concentrations by varying either

opera ting or control device conditions f or utilities commonly using baghouse technology to control PM. The commenter believed the “you must attempt” language should be replaced with wording that obtaining three different PM concentrations is the preferred appro ach for correlating a

PM CEMS , and Section 8.6(5) should be referenced as an acceptable alternative. (0032)

Response : These comments will be addressed separately in the upcoming PS

- 11 revisions and guidance rule.

99. Comment : Section 8.8(1) and (2) detail additional correlation testing if the CEMS responses are greater than 125 percent of the highest PM CEMS response used for the correlation curve “while your source is operating under
normal conditions.” The commenter believed that, by not providing a definition for “normal conditions,” it was unreasonable to require additional correlation testing when

responses were greater than 125 percent as a result of

start

- up, shutdown, or malfunction s

. It was note d that
correlation testin g is not performed during start

- up, shut down, or malfunction events, and it doesn’t make sens e to count responses greater than 125 percent that occur during such periods. (0029)

Response : These comments will be addressed in the upcoming

PS

- 11 revisions and guidance rule.

P S

- 12B

100. Comment : A commente r noted that the references in Table

12B

- 1 of Performance Specification 12B (PS

- 12B) of Appendix B to part 60 of 40 CFR to “Section 12.7.1.3” should be to “Section 12.8.3.” (0043)

Response : The EPA agrees with the commenter that the noted
references in Table 12B

- 1 of PS

- 12B of Appendix B to part48

60 are incorrect. Though we did not propose any revisions

to P S

- 12B in Appendix B to 40 CFR part 60 in this rulemaking, we believe this correction should be made an d we are, therefore, revising Table 12B

- 1 of P S

- 12B to
correct the references.

101. Comment : A commenter recommended that P S

- 1 2B address the consequences of data loss when one of sample sorbent traps is lost, broken, or damaged. The commenter noted that

Perfo rmance Specification 12B was based on Appendix K of Part 75 which require d the remaining good trap meet all applicable quality assurance requirements and the mercury concentration measured by that trap be multiplied by a

factor of 1.111. The commenter reco mmended this language be

added to P S

- 12B. (0043)

Response : Though we did not propose to make any revisions

to P S

- 12B of Appendix B to 40 CFR part 60 in this rulemaking, we believe this is an addition that should be made to prevent invalidating data that are actually valid. As the commenter pointed out, P S

- 12B already includes provisions for using the results from a single sorbent trap when one of the two sorbent traps fails certain acceptance criteria, but it does not include a specific provision
addressi ng the case where one trap is lost, broken, or damaged. We are, therefore, adding specific language to
Section 12.8.3 of P S

- 12B to specifically address the case where one sample trap is lost, broken, or damaged.

102. Comment : In proposed and promulgated PS

- 12B, Table 12B

- 1, the ratio of stack gas flow rate to sample flow must not deviate by more that 25 percent from the ratio recorded in
the first hour of data collection or the data must be invalidated. In the proposal, deviati ons up to five percent of the hourly ratios or 5 hourly ratios (whichever is less restrictive) were also allowed. A commenter believed this relief was needed to reduce the likelihood of complete data loss from both traps for periods of up to 14 operating

d ays. It was noted that the EPA did not address why the
allowance was not included in the final rule nor was there a negative public comment from its proposal. (0043)

Response : Though we did not propose to make any revisions

to P S

- 12B of Appendix B to 40 CFR part 60 in this rulemaking, the EPA believes that the commenter makes a valid point that this minor flexibility that was dropped from the language between proposal and promulgation is49

warranted to avoid invalidating valid data. We are, therefore, incor porating the language into Table 12B

- 1 from the original proposal that allows for deviation from the proportional sampling reference ratio criteria of + 25 percent for no more than five percent of the hourly values or 5 hourly ratios, whichever is less rest rictive.

PS

- 15

103. Comment : A commenter noted that in updating Performance Specification 15 ( PS

- 15 ) to reference the relative accuracy procedure in PS

- 2, no acceptability criteria for the relative accuracy test were given. A referenc e to Section

13.0 of PS

- 2 was suggested. (0029 , 0032 )

Response : P S

- 15 references the relative accuracy procedures in PS

- 2 which includes the acceptance criteria.

PS

- 16

104. Comment : Three commenters supported the proposed changes
in Section 13.5 of Performance Specification 16 ( PS

- 16 )

. Two believed the change w ould make it easier to meet the RAA requirements in the low concentration range . ( 0032, 0033, 0037)

Response : No response is necessary.

Appendix F

– Procedure 1

105. Comment : A commenter wanted Procedure 1 to be revised in this rulemaking. First, the commenter believed the cylinder gas audit (CGA) ranges allowed for diluent CEMS should be based on a percentage of instrument span and not just on an absolute cylinder gas concentration. Second, the commenter believed diluent CEMS should be allowed an accuracy of 15 percent or ±0.5 percent O 2 or CO 2 . Third, the commenter thought it helpful to revise Section 5.1.4 to allow for postponement of a RATA due to “limited operation (e.g., <168 hrs), and not just when the unit is not operat ing at all. (0029 , 0032 )

Response : The commenter’s suggestions are appreciated but are beyond the scope of the proposed revision to Procedure 1. These suggestions will be retained and will be
considered in the next methods update package.50

Appendix F

– Procedure 2

106. Comment : A commenter supports the proposed correction to the denominator of Equation 2

- 4 and believes the revision is consistent with EPA’s original intent. (0032)

Response : No response is necessary.

Method 101A

107. Comment : A commenter noted that proposed Section 16.1.2

was mislabeled as 6.1.2. (0035)

Response : The commenter is correct, and t his error has

been corrected.

Method 107

108. Comment : One commenter asked that Method 107 also be revised in this rule although it was not revised in the proposal. The commenter desired that the calibration frequency be increased from the beginning and ending of an
8

- hr period to the beginning and ending of a 12

- hr period.
The commenter noted that the 8

- hr period was chosen by their predecessor company to correspond to their 8

- hr working shift. They felt a 12

- hr period would better fit many of the employee shift schedules used in many manufacturing plants tod ay. In a comparison study they performed, there was little average percent difference between calibrations performed over both intervals. (0041)

Response : This suggestion is significant enough to warrant a proposal for public comment. It will be catalog u ed for
inclusion in the next rule to update and correct the

method.

109. Comment : A commenter proposed an alternative method for determining total solids in Method 107. Currently, the method requires using a draft oven to dry resin samples.
Microwave technology was believed to be the modern approach since it is faster than draft ovens and allows companies to more quickly determine the residual vinyl chloride content of resin in production and make the process adjustments necessary to maintain complianc e. (0041)

Response : This suggestion is significant enough to warrant a proposal for public comment. It will be catalogued for51

inclusion in the next rule to update and correct the

method.

Part 63 Subpart ZZZZ

110. Comment : A commenter believed the proposed r evisions to Table 4 of the Stationary Reciprocating Internal Combustion Engines rule (Subpart ZZZZ) rule eliminated CO testing from Section 3 (Stationary RICE) as an option for performance testing. The commenter believed e liminating CO, and leaving

formald ehyde (EPA M e thod 320) as the only option for performance testing w ould be costlier for sources, and may cause compliance issues for sources who have already taken a proactive approach and completed performance testing using CO as the compliance method. (0 010 )

Response : Carbon monoxide testing was not eliminated in the proposed rule. What was eliminated was Method 1 or 1A for determining the number of traverse points for CO measurement. It was replaced by sampling from the centroid

of the exhaust.

Method 306

111. Comment : A commenter proposed the use of Teflon probe
liners and the option to heat the probe to stack temperature. The commenter noted that many of the stacks are not strong enough to support equipment. Being able to heat the probe would help with testing in the winter time. (0012)

Response : The commenter’s sugges tions are appreciated but are beyond the scope of the proposed revision to Method 306. These suggestions will be retained and will be considered in the next methods update package.

Method 316

112. Comment : One commenter strongly support s the use of Method 316 as an alternative method for formaldehyde from mineral
wool and wool fiberglass industries even though

. (0038)

Response : No response is necessary.