# Mandatory Greenhouse Gas Reporting Rule: EPA's Response to Public Comments

Subpart L – Fluorinated Gas

Production

# Subpart L – Fluorinated Gas

Production

U .S. Environmental Protection Agency Office of Atmospheric Programs Climate Change Division Washington, D.C.FOREWORD

This document provides responses to publ ic comments on the U.S. Environmental Protection Agency’s (EPA’s) Proposed Man datory Greenhouse Gas Reporting Rule:
Additional Sources of Fluorinated GHGs : Subpart L, Fluorinated Gas Production. EPA published a Notice of Proposed Rulemaking in the Federal Register (FR) on April 12, 2010 (75 FR 18652). EPA received comments on this proposed rule via mail, e-mail, and at a public hearing held in Washington D. C. on April 20, 2010. Copies of all

comments submitted are availa ble at the EPA Docket Center Public Reading Room. Comments letters and transcripts of the public hearings are al so available electronically through http://www.regulations.gov by searching Docket ID EPA-HQ-OAR-2009-0927.

EPA prepared this document in multiple sections, with each section focusing on a different broad category of comments on t he rule. EPA’s responses to comments are generally provided immediately following each comment. In some cases, EPA provided responses to specific comments or groups of similar comments in the preamble to the final rulemaking. Rather than repeating t hose responses in this document, EPA has referenced the preamble.

Comments were assigned to specific secti on of this document based on an assessment of the principal subject of the comment; however, some comments inevitably overlap multiple subject areas. For this reason, EPA encourages the publ ic to read the other
sections of this document rele vant to their interests.

November 2010 2

### Table of Contents

1 Definition of Source Category .............................................................................................. ... 1
1.1 F GHG Production Processes ........................................................................................ 1
1.2 CFC and HCFC Production Processes .......................................................................... 4
1.3 Transformation Processes ............................................................................................. 7 1.4 Coverage of emissions downstream of production measurement (other than transformation and destruction) ...................................................................................... 9
1.5 Other .................................................................................................................... ........ 12

2 Reporting Threshold .............................................................................................................. 13

3 No Comments ................................................................................................................. ...... 15

4 Detailed GHG Emission Calculation Procedures/Equations in the Rule ............................... 16 4.1 GWPs not Available for all F GHG Compounds ........................................................... 17
4.2 Mass Balance Calculations .......................................................................................... 20
4.2.1 - Mass Balance Error Calculation ........................................................................ 26 4.2.3 - Allow Alternative MB Approach for Transformation Processes ......................... 35
4.3 Emission Factor and Emission Calculation Factor Methods ........................................ 37 4.3.1 - Preliminary Estimate of Emissions by Process Vent ......................................... 38
4.3.2 - Cut-offs for Low-Emission or Controlled Process Vents ................................... 44 4.3.4 - Emission Factor Approach ................................................................................ 52 4.3.5 - Scope of the Emission Factor ........................................................................... 57 4.3.6 - Equipment Leaks .............................................................................................. 57 4.4 Allow Combination of Mass Balance, Process Vent testing and Engineering
Calculations .................................................................................................................. 73
4.5 Other .................................................................................................................... ........ 74

5 - Monitoring and QA/QC Requirements ................................................................................... 79 5.1 Initial Scoping Test ..................................................................................................... .. 79 5.2 Mass Balance Approach .............................................................................................. 89 5.3 Process Vent Emissions Factor Testing ....................................................................... 90 5.3.1 - Operating scenarios .......................................................................................... 90 5.3.2 - Identify Emission Episodes (e.g., using emissions profiles) .............................. 93 5.3.3 - Continuous Process Vent Emissions Factor Testing ........................................ 95 5.3.4 - Accuracy and Precision for Process Activity ................................................... 102 5.4 Allow Alternative Sampling and Analytical Methods (MB and process vents) ............ 105
5.5 Calibration Standards ................................................................................................. 11 1 5.6 Destruction Device Efficiency Determination ............................................................. 115 5.6.1 – Destruction Device Testing ............................................................................ 115

5.6.2 - Detection Limit Issues ..................................................................................... 121
5.6.3 - Hazardous Waste Combustors ....................................................................... 122
5.6.4 - Process Scrubbers Considered Destruction Devices ..................................... 123 5.6.5 - PIC Testing ..................................................................................................... 125

6 Procedures for Estimating Missing Data ............................................................................. 126

November 2010 3November 2010 4 7 Data Reporting Requirements ............................................................................................. 127 7.1 Confidentiality Concerns ............................................................................................ 127
7.2 Other comments ......................................................................................................... 13 3

8 Records that Must be maintained ....................................................................................... 142

9 No comments ................................................................................................................. ..... 142

10 Other subpart 1 comments .................................................................................................. 142
10.1 Definitions ....................................................................................................... 142
10.2 Effective dates ................................................................................................ 147
10.3 Other ............................................................................................................... 153Section 1 - Definition of Source Category

Section 1.1 - F GHG Production Processes

Commenter Name: Rob Rouse

Commenter Affiliation: The Dow Chemical Company

Comment Number: EPA-HQ-OAR-2009-0927-0119.1 Comment Excerpt Number: 8

Comment: Subpart L – Fluorinated Gas Production. EPA should clar ify the definition of this source category. The definition of this source ca tegory is highly depende nt on two definitions contained in existing §98.6 and proposed §98.128 respectively:

Fluorinated greenhouse gas means sulfur hexafluoride (SF 6 ), nitrogen trifluoride (NF 3 ), and any fluorocarbon except for controlle d substances as defined at 40 CFR Part 82 Subpart A and substances with vapor pressures of less than 1 MM of Hg absolute at 25 degrees C. With these exceptions, ‘‘fluorinated GHG’’ includes but is not limited to a ny hydrofluorocarbon, any perfluorocarbon, any fully fluorinated linear, branched or cyclic alkane, ether, tertiary amine or aminoether, any perfluoropolyeth er, and any hydrof luoropolyether.

Fluorinated gas means any fluor inated GHG, CFC, or HCFC.

There is potential confusion or uncertainty in the definition of Fluorinated Greenhouse Gas, and by extension the definition of fluorinated ga s. Although Dow agrees with the listing of compounds and families of compounds specified w ithin the definition of Fluorinated Greenhouse Gas, Dow disagrees with the inclusion of th e unnecessary, ambiguous phrase “...includes but is not limited to.” The addition of this phrase reduc es the clarity and specificity of the definition while introducing ambiguity for parties obligated to report. To correct this shortcoming, Dow suggests that EPA define “fluorin ated GHG” as any fluorinated GHG that is listed in Table A-1 of the proposed rule. The suggested change w ould make the rules very clear and unambiguous.

Response: Under this rulemaking, EPA did not open the definition of fluorinated GHG for

comment. We have determined that this defin ition provides sufficient clar ity regarding the scope

of the rule. 1 Please see the October 2009 preamble Section III.OO (74 FR 5620) for Subpart OO: Suppliers of Industrial GHGs, as well as the response to comments document on the same,

for more discussion of the defi nition of fluorinated GHG. We are not aware of any reason why

we should use a different defini tion of fluorinated GHG for this subpart than for the mandato reporting rule as a whole. ry

The definition of “fluorinated gas” that was included in the April 2010 proposed rule differs

from the definition of “fluorinated GHG” by including chlorofluorocarbons (CFCs) and

1 Note that the first sentence of the definition clearly establishes the full set of included compounds, while the second sentence provides examples. In the context of th e second sentence, the phrase “includes but is not limited to” is not ambiguous, but highlights the fact that the type s of compounds subsequently li sted are examples that do not necessarily exhaust the set of compounds included by the first sentence.

1hydrochlorofluorocarbons (HCFCs) in addition to fluorinated GHGs, but the commenter does not provide any comments regarding the incl usion of CFCs and HCFCs.

Commenter Name: Ross Smith

Commenter Affiliation: PCS Phosphate Company, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0084.1 Comment Excerpt Number: 1

Comment: EPA should clarify exactly what compounds are subject to this Subpart L. The

current definition of fluorinated GHG states , "Fluorinated greenhouse gas means sulfur hexafluoride (SF 6 ), nitrogen trifluoride (NF 3 ), and any fluorocarbon except for controlled

substances as defined at 40 CFR part 82, subpart A and substances with vapor pressures of less than 1 m Hg absolute at 25 degrees C. With th ese exceptions, "Fluorinated GHG” includes, but is not limited to, any hydrofluorocarbon, any perf luorocarbon, any fully fluorinated linear, branched, or cyclic alkane, ether, tertiary am ine or aminoether, any perfluoropolyether, and any hydrofluoropolyether."

There are many compounds that meet this defi nition, but do not appear in Table A-1 of the current rule. EPA should clearly state, in the co ntext of Subpart L, the compounds that meet the

definition of fluorinated GHG and which appear in Table A-1, pr oviding clarification that this part of the determination is not exclusive of the other.

Response : The definition of “fluorinated GHG” ra ther than Table A-1 defines the set of fluorinated compounds that faciliti es must monitor and report, and EPA has determined that this definition provides sufficient clarit y regarding the scope of the rule. For more discussion of this issue, please see the response to comment number EPA-HQ-OAR- 2009-0927-0119.1, excerpt 8.



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-106.1 Comment Excerpt Number : 9

Comment : EPA should revise the perfluorocarbo n (PFC) definition to indicate PFCs are compounds of carbon and fluorine and that all carbon bonds are fully saturated (only single bonds) where IPCC has identified a GWP. EPA shoul d also revise the hy drofluorocarbon (HFC) definition to include only those liquid or gaseous (not including fluoropolymers) compounds containing between one and si x hydrogen, fluorine, and carbon compounds identified by IPCC

with a GWP.

Response : Under this rulemaking, EPA did not open the definition of perfluorocarbon (PFC) and hydrofluorocarbon (HFC) for comment.

2Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 8

Comment: Section 98.121 applicability references in error. EPA: Section 98.121 states: “You must report GHG emissions under this subpart if your facility contai ns a fluorinated gas production process that genera tes or emits fluorinated GHG and the facility meets the requirements of either section §98.2(a)(1) or (a )(2).” The preamble on page 18670 states; “Under this proposal, subpart L would re quire facilities that produce fluorinated ga ses to report their

fluorinated GHG emissions from fluorinate d gas production and transformation and from

fluorinated GHG destruction.” Comment: The rule limits applicability to industries specified in §98.2(a) (1) and a (2), whereas the preamble word ing is broader. The preamble should clarify applicability only applies to the proce sses listed in §98.2(a) (1) and a (2).

Respons e: The final rule remains unchanged regarding applicability as specified in §98.121, which points to the list of sour ce categories and the reporting thre sholds in subpart A. As proposed (75 FR 18689), EPA is amending subpart A to add “fluorinated gas production” to the list of emission threshold source categories refe renced in the appropr iate subpart A table (specifically, Table A-4 to subpart A). See the pr eamble of the final rule for more discussion of this amendment. The source category itself is de fined at §98.120. Note that the definition of the source category at §98.120, along with the re porting threshold at §98.121, determine which facilities must monitor and report their fluor inated GHG emissions from fluorinated gas production and other GHG-emitting processes. Howe ver, it does not define the full set of processes whose emissions must be reported under subpart L. Those pr ocesses include not only fluorinated gas production, but fl uorinated gas transformation, fluorinated GHG destruction, and venting of residual fluorinate d GHGs (see §98.122 and the specific calculation, monitoring, and reporting requirements of subpart L).

Commenter Name: Giedrius Ambrozaitis

Commenter Affiliation: Alliance of Automobile Manufacturers

Comment Number: EPA-HQ-OAR-2009-0927-0090.1 Comment Excerpt Number: 2

Comment: EPA should list reportable compounds and only require reporting for compounds greater than GWP 150. To further provide an in centive to switch to using low GWP compounds, EPA should establish a specific list of which co mpounds need to be reported and should set a reporting threshold to only include compounds w ith GWPs greater than 150. This list should exclude compounds which have a low GWP, i.e ., compounds which are de minimis in nature.

We recommend that 150 GWP be used as the th reshold below which GHGs are considered de minimis and would not require reporting. In a ddition to minimizing tracking and reporting burdens, this would incentivize importers and exporters to switc h more quickly out of high GWP

GHGs.

3Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0119.1, excerpt 8, as well as the 2009 Response to Co mments Volume 2 – Selection of Reporting Thresholds, Greenhouse Gases, and De Mini mis Provisions, respons e to comment EPA-HQOAR-2008-0508-0793.1, excerpts 1 and 2 ( p. 7- 9). Note that even with a GWP of 150, if a compound is emitted in large quantities, it could still be a significant source of emissions.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 2

Comment: EPA appropriately limits Subpart L applicability to exclude reporting facilities subject to Subpart O, hydrochlorofluoro carbon (“HCFC”)-22 Producti on and hydrofluorocarbon (“HFC”)-23 Destruction. EPA s hould clarify the §98.120 (a) language to specifically reference Subpart O, instead of describing Subpart O w ithout a direct reference. EPA should also explicitly exclude any activities being reported under Subparts OO or QQ of Part 98, the fluorochemical marketing reporting rules, as outside Subpart L applicability.

Response: We have concluded that it is clearest to define the fluorinated gas production source category by explicitly describing the activities that are included and excluded at §98.120. Section 98.120(a) excepts “processes that genera te HFC-23 during the production of HCFC-22.” (Note that this exception applies to processes rather than facilities; fluorinated GHG emissions from fluorinated gas production processes th at are co-located with HCFC-22 production processes at the same facility must be reporte d under subpart L.) The requirement to report emissions of HFC-23 from production of HCFC-22 under subpart O rather than under subpart L is already clearly stated at §98.122(b) (as it was in the April 2010 proposed rule): “You must report under subpart O of this part (HCFC-22 Production and HFC-23 Destruction) the emissions of HFC-23 from HCFC-22 production processes and HFC-23 destru ction processes. Do not report the generation and emissi ons of HFC-23 from HCFC-22 pr oduction under this subpart.”

We are in some cases requiring reporting under su bpart L of quantities th at are also reported under subpart OO. The rationale for this reportin g is discussed further in the preamble to the final rule and elsewhere in this response to co mments document. (Please see, e.g., the responses to comment number EPA-HQ-OAR-2009-0927-0117.1, excerpt 10 in section 7 and comment number EPA-HQ-OAR-2009- 0927-0103.1, excerpt 6b.)

Section 1.2 - CFC and HCFC Production Processes

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 3

Comment : HFC emission reporting fr om CFC production is not warra nted. EPA: On page 18671 of the preamble, EPA requested comment on “the extent to which fluorinated GHGs are

4generated and emitted during CFC and HCFC pro duction.” Comment: We do not detect any HFCs in our CFC production pro cesses. Based on a detection limit of 0.1%, and an emission rate of 0.03% of total CFC production (based on 2009 emissions estimates from one of our CFC intermediate processes), th en the maximum HFC emissions would be 0.00003% of CFC production, more than four orders of magnitude less than the EPA estimation of 1%. Hence, HFC emissions from CFC production would be reported as "zero" at the 0.1% detection limit, and HFC emissions reporting from CF C production is not warranted.

Response: In the final rule, EPA is retaining production of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) in the defini tion of the fluorinated gas production source category. However, we are also clarifying that fluorinated GHGs that occur in process and emission streams only in trace concentrations are exempt from the monitoring requirements. In addition, we are clarifying that the scoping specia tion requirement applies only to processes that have at least one process vent with uncontrolled emissions of 1.0 metric ton or more of fluorinated GHGs per year based on the prelimin ary estimate of emissions in §98.123(c)(1).

We believe that together, these clarificatio ns and revisions will generally address the commenter’s concerns regarding reporting of extremely small c oncentrations and quantities of

fluorinated GHGs in CFC and HC FC production processes. Give n the considerable nationwide production of CFCs and HCFCs, as well as th e recognized tendency of many CFC and HCFC production processes to genera te fluorinated GHG by-products, 2 we have concluded that these clarifications are preferable to an across-the-board exclusi on of CFC and HCFC production processes from subpart L. U.S. production of CF Cs and HCFCs is consid erable, on the order of 266,000 tons/yr (not including HCFC-22), and even if fluorinated GHGs are generated and emitted at relatively low rates from these proce sses, the total fluorinated GHG emissions may be significant. While the commenter notes that th e emission percentage is small for the one CFC intermediate process noted, at other facilities a nd for other processes, the emissions percentage may be larger.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 7

Comment: EPA should not require emission reporti ng for processes where FGHGs are neither reactants nor products. EPA: On page 18671 of the rule preamble, EPA is requesting comment to require reporting for emissions from pro cesses where FGHGs are neither reactants nor products of the process but are by-products or intermediates. Comment: Determining applicability is already rather complicated fo r subpart OO and L. Changing applicability based on FGHG by-products and intermediates will fu rther complicate understa nding and application of the rules. Tracking and monitoring small con centrations across a process will also be difficult to do with accuracy. Additionally, for raw materials and products that are not FGHGs due to vapor pressure, by-products, intermediates and impurities are likely to be low vapor pressure

2 See the preamble of the proposed rule as well as the Te chnical Support Document for more discussion of these

issues.

5materials as well, with insigni ficant FGHG emissions. DuPont ha s several low volume low vapor pressure fluoromonomer products that are not FGHGs due their vapor pressure being less than 1 mm Hg. However, a 0.5% generated impurity in this product has a vapor pr essure slightly over the 1 mm Hg threshold. Under EPA’s contemplat ed expanded regulatory applicability scheme, the regulated impurity would subject the impurity, product, and raw material process streams to the costly FGHG monitoring, repo rting and recording requirements. The annual production of one our higher volume fluoromonomer non-F GHG product is in the range of 1000 to 2000 metric tons (mtn)/yr. Since the FGHG component is small, and its vapor pressure low, its emissions are very small, estimated to be less than 0.01 mtn/yr. The atmospheric lifetime of this impurity is short, and hence its GWP is low, estimated to be less than 50. Including these kinds of products and processes in the regulatory scheme is not cost effective. Alternatively, if EPA adopted a definition of trace that included not onl y the 0.1 % definition, but also included either a reasonable mass based trace exemp tion (such as 5 tons/yr), or a CO 2 e calculated exclusion of 10,000 mtn/yr, the rule could be practical. With mass or CO 2 e alternatives in the trace exclusion, inclusion of by-products and intermed iates would be less burdensome.

Response: In the final rule, EPA is not requirin g reporting of fluorinated GHG emissions from processes where fluorinated gase s are neither reactants nor produc ts. We did not include such processes in the proposed rule and have concluded that it is not appropriate to include them in

the final rule for the reasons cited by the commenter.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 5

Comment: ACC members do not dete ct fluorinated GHGs in the CFC and HCFC production processes at a detection limit of 0.1%, therefore, these emission s would be reported as either

“zero” or “at detection limit.” We do not beli eve that the burden imposed by monitoring and reporting of these emissions justif ies the resulting reported data.

Response: Please refer to the response to comment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 3.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 4

Comment: Carbon tetrachloride and methyl chloroform emissions should not be regulated by Subpart L. EPA: On page 18671 of the preamble it also requests comment on: “the extent to which fluorinated GHGs may be generated a nd emitted during production of other ozonedepleting substances such as methyl chlorofo rm and carbon tetrachloride and on whether such emissions should be reported under this rule.” Comment: There are no fluorinated reactants

6present in the production proce sses for carbon tetrachloride and methyl chloroform. As such, there is no mechanism for HFC co-production no r emissions. Carbon tetrachloride and methyl chloroform process emissions should not be addressed in subpart L.

Response: EPA is not including production of chlorocarbons in the definition of the fluorinated gas production source category for the reasons cited by the commenter.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 4

Comment: EPA appropriately distinguished th e production of a fluorinated GHG from production of chlorocarbons in §98.120. EPA corre ctly does not require subpart L reporting from carbon tetrachloride or methyl chloroform production processes, as there are no fluorinated

reactants in either production process.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 4.

Commenter Name: Rob Rouse

Commenter Affiliation: The Dow Chemical Company

Comment Number: EPA-HQ-OAR-2009-0927-0119.1 Comment Excerpt Number: 9

Comment: This Source Category should not incl ude the production of non-fluorinated compounds. EPA specifically requested comments on the extent to which fluorinated GHG’s may be generated during the pr oduction of other ozone-depleting substances, such as methyl chloroform and carbon tetrachloride. Dow operates multiple chlorinated organics plants in the US. There are no fluorinated reactants present in these production processes. As such, there is

neither a mechanism for HFC of fluorina ted GHG co-production nor emissions. Carbon Tetrachloride and Methyl chloroform process emi ssions should not be addressed in subpart L.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 4.

Section 1.3 - Transformation Processes

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 9

7Comment: Subpart L should not apply to non-emissi ve products. EPA: §98.122(c) states “You must report the total mass of each fluorinated GHG from (2) each fluorinated gas transformation process that is not part of a fluorinated gas production pro cess ...” Comment: EPA should exempt from reporting any fluorinated compounds th at are not placed into subsequent emissive uses. This approach was taken in the ozone depleting substance program (40 CFR Part 82), where ozone depleting substances that are transformed in s ubsequent use to non-emissive compounds are exempt from the program.

Response: We are finalizing the proposed requireme nt that facilities report fluorinated GHG emissions from processes that transform fl uorinated gases into other compounds, including compounds that are not themselves fluorinated GHGs . As discussed in the proposed rule, such transformation processes can emit fluorinated GHGs th at are fed into the process as reactants or that are created as by-products. The focus of subpa rt L is on these and other emissions that occur at facilities that pr oduce fluorinated gases. The 40 CF R part 82 regulations cited by the commenter are largely concerned with additions to and subtractions from the supply of ozonedepleting substances available for emissive use, but the part 82 regulations do include requirements for reporting the production of ozon e-depleting substances even if they are

transformed into substances that do not deplete the ozone layer.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 8

Comment: Further, some facilities may produce fluorin ated gases that are used as intermediates in subsequent chemical synthesis by customers at their facilities, yieldi ng a final product in

which there are no emissions of the fluorinated compound of concern. EPA should exempt from reporting any fluorinated compounds that are not placed into subs equent emissive uses. This approach was taken in the ozone depleting s ubstance program (40 CFR Part 82), where ozone depleting substances that are transformed in subsequent use to non-emissive compounds are exempt from the program.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 9.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 6a

Comment : It is DuPont’s experience that most o ff-site transformations involve manufacturing

less volatile fluoromonomer and fluoropolymer molecules and therefore are not significant

contributors to F-GHG CO 2 e emissions.

8Response: EPA is not requiring reporting of fluo rinated GHG emissions from transformation processes that are not co-located with fl uorinated gas production processes.

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number: 11

Comment : The Alliance requests that EPA reeval uate the overlap between Subpart OO and Subpart L in regard to the Subpart OO re quirement to report onsite transformation of

fluorocarbon material that is also produced and used onsite. Such fluorocarbon material has never entered commerce or in many cases been is olated, rendering its re porting under Subpart OO unnecessary. Operations involving onsite fluorocarbon production followed by onsite

transformation should be excluded from the re porting requirements of Subpart OO while the

emissions from such activities should be reported solely under Subpart L.

Response: The final subpart L requires fluorinated gas production facilities to report emissions of fluorinated GHGs from processe s that transform fluorinated gase s. In a separate rulemaking, EPA has proposed to amend subpart OO to exem pt from reporting ( under that subpart) fluorinated GHGs that are produced and transformed at the same facility; please see the proposed

rule at 75 FR 48744.

Commenter Name: Peter Zalzal

Commenter Affiliation: Environmental Defense Fund

Comment Number: EPA-HQ-OAR-2009-0927-0067 Comment Excerpt Number : 3

Comment : EDF also encourages EPA to include fluor inated gases that while neither reactants nor products are generated as byproducts, ar e intermediaries of another reaction.

Response : Please see the responses to comment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 7, and comment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 3.

Section 1.4 - Coverage of emissions downstrea m of production measurement (other than transformation and destruction)

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 6b

Comment: Other downstream emission points should not be included in Subpart L reporting. EPA: On page 18672 of the preamble, Sec 3 Defi nition of Source Category, last paragraph, EPA

9requests comment on the magnitude of other on-s ite emissions that o ccur at fluorinated GHG production facilities downstream of the production measurement and whether or not they should be required to be reported under subpart L. Co mment: These other on-site emissions should not be required to be reported since the volume is already included in the measured production volume (double counting potential) and they repres ent a very small amount of the production volume. Having differing rule applicability for subparts OO and L will further complicate understanding and application of the rule.

Response: In the proposed rule, EPA requested co mment on requiring repor ting under subpart L

of emissions that occur at fluorinated GHG production facilities after the production measurement (other than emissions from fl uorinated GHG transformation and destruction processes). We specifically re quested comment on the desirability of including emissions from cylinder filling, blending of fluorinated GHGs, recycling or reclamati on of fluorinated GHGs,

and evacuation of fluorinated GHG heels from re turned cylinders. We noted that these emissions are reported as supply under subpart OO, but that some reporting under L of emissions that are counted as supply under OO is appropriat e to inform the range of possible policies to reduce emissions of GHGs. This range includes “upstream” approaches focused on supply and “downstream” approaches focused on act ual emissions where they occur.

In the final rule, we are not requiring re porting of emissions from cylinder filling (e.g., disconnect losses), from ble nding of fluorinated GHGs, from equipment leaks beyond the production measurement, or from recycling or recl amation because these emissions appear to be small based on our research and public comments. However, as discussed in the preamble of the final rule, we are requiring reporti ng of emissions from venting of residual fluorinated GHGs in

returned containers because our research has sh own that these emissions can be significant at some facilities. (See the Techni cal Support Document for more di scussion of this issue.)

To avoid double-counting, we are requiring facilities to report em issions that are counted as supply under subpart OO separately from emissions that are not counted as supply under OO. Thus, facilities are required to separately report fluorinated GHG emissions from transformation of fluorinated GHGs that are produced off-site, from destruction of fluorinated GHGs that are sent to the facility for destruction (e.g., from the field or from other facilities), and from venting

of residual fluorinated GHGs in returned containe rs. These requirements are straightforward and we do not expect them to cause confusion.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0085.1 Comment Excerpt Number: 6

Comment: At 75 Fed. Reg. 18672/2, EPA requests co mment concerning the magnitude of onsite emissions events that may be best desc ribed in Subpart OO activities. The most common

situation is the trivia l portion of disconnect losses from packaging FGHGs at or beyond the custody transfer point. Arkema’s experience with ozone depleting substa nce (“ODS”) disconnect

losses has shown that ODS disconnect losses amount to less than 0.01% of total ODS

10production. Subpart OO assumes that all materials passing the custody transf er point will either be emitted, transformed, or recycled. Any Part 98 reporting of these post-transfer point emissions is best managed in Subpart OO. Emissions befo re the transfer point should be reported in Subpart L. Fugitive emissions past the custody transf er point are the second part of post-transfer point secondary emissions. We ll over 99% of the fugitive equi pment component count in FGHG service in the Arkema FGHG production units are before the custody transfer point. Total equipment leak losses past the custody transfer po int are expected to be insignificant, partially due to the very limited number of components, the need to maintain the product handling and distribution systems under adequate pressure to maintain invent ory, and to maintain adequate product quality specifications. Because any post- custody transfer point emissions, as a trivial source of FGHG emissions, are allocated in Subpa rt OO, Subpart L repor ting is not necessary.

Response : Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 6b.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 7

Comment: In addition, on page 18672 of the preamble, the last paragraph in the Definition of Source Category discussion request s comment on the magnitude of other on-site emissions that occur at fluorinated GHG production facilities do wnstream of the production measurement and whether or not they should be required to be reported under subpart L. These other on-site emissions should not be required to be reported since the volume is already included in the measured production volume (double counting pote ntial), and they represent a very small amount of the production volume.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 6b.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 8

Comment: In B. Fluorinated Gas Production, Secti on 3, page 18672 of the preamble, Definition of Source Category, the last paragraph request s comment on the magnitude of other on-site emissions that occur at fluorinated GHG pr oduction facilities downstr eam of the production measurement and whether or not they should be required to be reported under subpart L. These other on-site emissions should not be required to be reported since the volume is already included in the measured production volume (doubl e counting potential), and they represent a very small amount of the production volume.

11Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 6b.

Section 1.5 - Other

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 6

Comment : We agree with EPA’s understanding and do not expect significant emissions from wastewater and storage tanks fo r the reasons discussed in the preamble. Most fluorinated GHGs have low solubility in water, and the majority of fluorinated GHG processes do not typically

generate wastewater streams. Those processes that do genera te wastewater streams would

therefore not transfer fluorinated GHGs into the aqueous phase inside the process during a washing step. Storage tanks are pr essurized units and would not ge nerate the typical working and breathing emissions associated with this type of equipment. Our experience with container filling

is also consistent with the discussion in the preamble. Container filli ng takes place after the fluorinated GHG production facilities measure their production, so the volume would have already been included and reported in the Subpart OO production measurement.

Response: EPA appreciates the inpu t on its request for comment on other types of emission points at fluorinated gas produc tion facilities and the magnitude of emissions from these emission points. The promulgated rule for subpart L does not include requirements for reporting of emissions from wastewater streams, storage ta nks, or container filling for the reasons cited in the April 2010 proposed rule and by commenters.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 5

Comment: Storage tank and wastew ater emissions should not be included in Subpart L reporting. EPA: On page 18680 of the preamble, EPA requested comment on emissions from storage tanks and wastewater. Comment: We agree with EPA’s understanding and do not expect significant emissions from wastewater and storage tanks for the reasons mentioned in the Preamble. The majority of FGHG processes do not generate wastewater st reams, and for those that do, most fluorinated GHGs have low solubility in water, and would therefore not transfer into the aqueous phase inside the process durin g a washing step. Storag e tanks are pressurized units and would not generate the typical working and breathing emissions associated with this type of equipment. Our experience with container filling is also consiste nt with the Preamble. Container filling typically ta kes place after the fluorinated GHG production facilities measure their production, so the volume would have alrea dy been included and reported in the Subpart OO production measurement.

12Response : Please see response to comment number EPA-HQ- OAR-2009-0927-0092.1, excerpt 6.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 15

Comment: In B. Fluorinated Gas Production, Section 5.d., EPA requests comment on the

inclusion of fluorinated GHG emi ssions from storage tanks, wast ewater, and container filling, anticipating that these emissions would be small to insignificant due to low solubility of most fluorinated GHGs in water and the use of pressu rized vessels for storag e. Air Products concurs with the position that the emissions would be very small to insignificant for the reasons stated and do not anticipate significant emissions from wastewater and storage tanks for the reasons discussed in the preamble. Most fluorinated GHGs have low solubil ity in water, and the majority of fluorinated GHG processes do not even generate wastewater st reams. Those processes that do

generate wastewater streams w ould therefore not transfer fluo rinated GHGs into the aqueous phase inside the process during a washing step. St orage tanks are pressuri zed units and would not generate the typical working and breathing emissions associated w ith this type of equipment.

Response: Please see response to comment number EPA-HQ- OAR-2009-0927-0092.1, excerpt 6.

Section 2 - Reporting Threshold

Commenter Name: Ross Smith

Commenter Affiliation: PCS Phosphate Company, Inc

Comment Number: EPA-HQ-OAR-2009-0927-0084.1 Comment Excerpt Number: 2

Comment: The applicability for this Subpart is based on uncontrolled emissions threshold of 25,000 metric tons (mt) car bon dioxide equivalent (CO 2 e) threshold. Many of the fluorinated GHGs identified in Table A-1 have such high Glob al Warming Potential (GWP), that they would only be able to emit slightly more than 1 mt of the compound and exceed the threshold. The

threshold would be better suited as a mt of each compound (i.e., 10 mt fluorinated GHG) rather

than on a CO 2 e basis. This will enable EPA to make a threshold which will capture the large emitters, but will not affect smaller facilities, ev en if they emit more potent greenhouse gases. Additionally, the threshold should be on a post-control basis, in which comparison of actual

emissions to the threshold is used to determine a pplicability, consistent w ith the approach for the other Subparts of this Part. The use of actual emissions for determining threshold exceedance

would also be consistent with EPA’s proposal to use actual emi ssions for determining whether a facility could discontinue reporti ng. The approach for determining ap plicability, or the ability to discontinue reporting, should be on a consistent basis, either a ll pre-control or a ll post- control.

13Response: In the final rule, we are adopting the proposed threshold of 25,000 metric tons of

CO 2 e, uncontrolled. The use of metric tons of carbon-dioxide equivalent (CO 2 e) rather than

metric tons of fluorinated GHG in the threshold is consistent with th e definition of emission thresholds throughout the Mandato ry GHG Reporting Rule. Carbon- dioxide equivalents (and the global warming potentials develope d to calculate them) have been developed as a means of comparing GHGs based on their ability to trap he at in the atmosphere over a specific time horizon, and they are widely used in internati onal reporting of GHG emissions and sinks and in GHG policy analyses. A facility that emits one ton of SF 6 (with a 100-year GWP of 23,900) has an impact on climate forcing over the next 100 years th at is almost four times as large as that of a facility that emits five tons of HFC-134a (with a 100-year GWP of 1300). Thus, defining a

threshold in terms of tons of fluorinated GHG could result in requiring reporting from facilities that contribute comparatively little to climat e forcing, while exempting from reporting facilities

that contribute much more. The result woul d be a reporting program that captured a smaller

share of CO 2 -equivalent emissions and/or disproportionately burdened facilities with relatively

small CO 2 e emissions. Hence, to ensure that this rule efficiently and effectively collects the information necessary to fully inform GHG polic ies and programs, the reporting threshold is

defined in terms of CO 2 e rather than tons of fluorinated GHG.

EPA is finalizing the uncontrolled emissions threshold for this source category because facilities may overestimate their destruction, and cons equently underestimate their emissions, of

fluorinated GHGs. As discussed in the preamble of the final rule, some fluorinated GHGs, particularly CF 4 and SF 6 , are very difficult to destroy. In f act, they are more difficult to destroy than the compounds that are typi cally used to establish destru ction efficiencies (DEs) for hazardous waste combustors (i.e., the Class 1 co mpounds in the thermal stability rankings in Appendix D to EPA’s “Guidance on Setting Permit Conditions and Reporting Trial Burn Results.”) Facilities may underestimate em issions of such compounds because they are inappropriately applying a DE established for a compound that is actually easier to destroy, or because, as noted in the April 2010 proposed rule , they are not aware of the full range of byproducts generated by their processes in the firs t place. The DE testing and scoping speciation provisions of the rule are inte nded to address these possibilitie s. Once a facility has (1) definitively identified the compounds that are generated and emitted by its processes and (2)

established the DE of its destru ction device for the compounds that are vented to the device, the facility’s conclusions about its own controlled emi ssions will be more reliable. (This reliability will be further enhanced by the rule’s inclusion of provisions to address emissions that occur during destruction device malfunctions.) For th ese reasons, it is not inconsistent to use

uncontrolled emissions for the initial threshold determination and controlled emissions for determining eligibility for the “off-ramp” provi sions at §98.2(i).

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0084.1-0085.1 Comment Excerpt Number: 7

14Comment: At 75 Fed. Reg. 18673/2, EPA requests co mment on the Subpart L applicability threshold basis. EPA proposed to base the S ubpart L reporting threshold on precontrol FGHG emissions. Any reporting off ramp should be base d on the same precontrol emissions basis. For fluorinated product lines emitting FGHGs with no Part 98 Table A-1 global warming potential (“GWP”) values, EPA should adopt a similar appr oach to the reporting of such compounds used in the Subpart OO in effect when Subpart L reporting begins. A mass- based approach, where only facilities emitting a relativel y small amount of FGHGs without GWP values (for example, <1 ton per year) escape reporting, meets EPA’ s comprehensive reporting goals. EPA should maximize Subpart L reporting to as much of the fluorochemical indu stry as possible.

Response : Please see response to comment number EPA-HQ- OAR-2009-0927-0084.1, excerpt 2.

Commenter Name: Craig Holt Segall

Commenter Affiliation: Sierra Club

Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number: 11

Comment: We support EPA’s decision to set a re porting threshold of no more than 25,000

mtCO 2 e, which could embrace as much as 100% of a ll emissions. Indeed, because essentially all of the 14 production facilities woul d be covered at any threshold, we suggest EPA consider using a simple “all-in” approach for this category, which would eliminate the technical complexities

facilities would otherwise face in dete rmining compliance with the threshold.

Response: EPA appreciates your comment. In order to allow for the exclusi on of facilities that emit very little fluorinated GHG on a CO 2 e basis, EPA is not adopting an all-in approach. This is because some subsections of the industry, e.g. , HFE manufacturers, are generally comprised of small production facilities. A lthough HFE manufacturers may ge nerate by-products with high GWPs, their emission rates are much smaller than that of other production facilities. Thus, EPA is not adopting the all-in a pproach in order to reduce the burden on small facilities.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 10

Comment: In B. Fluorinated Gas Production, Sec tion 4, EPA requests comments on the option of eliminating the threshold for fluorinated gas production facilities and making this an “all-in” category. Air Products s upports this option.

Response : Please see response to comment number EPA-HQ- OAR-2009-0927-0128.1, excerpt 11.

Section 3 – No comments

15Section 4 - Detailed GHG Emission Calcul ation Procedures/Equations in the Rule



### Commenter Name: Peter Zalzal


### Commenter Affiliation: Environmental Defense Fund


### Document Control Number: EPA-HQ-OAR-2009-0927-0067 Comment Excerpt Number : 7

Comment: Lastly, EDF shares the Agency’s interest in accurate, reliable data and we recognize that system-wide accuracy can often be achieve d through a combination of monitoring methods. We know that EPA has generally expanded the m onitoring methods available to fluorinated gas facilities including proposing a refined met hod for estimating emissions factors from

semiconductor facilities in lieu of the 2006 IPCC Tier 3 method and allowing producers of fluorinated greenhouse gases increased flexibil ity in using mass balance measurements to monitor their emissions. EDF encourages the Agen cy to ensure that these revised methods do indeed provide accurate data and we look forwar d to providing more detailed analyses of the proposal in our wr itten comments.

Response: EPA appreciates the commenter’s support in its efforts to provid e flexible, accurate monitoring methods to facilities in the fluorinated gas production source category.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Commenter Excerpt Number : 8

Comment: EPA appropriately proposes, at pr oposed 40 CFR 98.123, to allow reporting facilities two options to report actual FGHG emissions from fluor ochemical production facilities. The amended mass balance approach, using a relati ve error accuracy appr oach instead of the absolute error approach in the 2009 proposal, is a substantial improvement from the 2009 proposed Subpart L mass balance system. EPA a ppropriately recognizes that a mass balance could be subject to substantial error. We s upport the error bounds at proposed §98.123(a) where reporters who cannot demonstrat e acceptable error in a mass ba lance across a process must utilize the proposed 40 CFR §98.123(b) emission f actor estimation method. Arkema appreciates

EPA’s serious consideration of our June 2009 co mments suggesting a Subpart L emission factor based reporting system. EPA appropriately inco rporated several maximum achievable control technology (“MACT”) concepts from various 40 CFR 63 subparts into th is Subpart L proposal. EPA appropriately recognized that many of th e FGHG manufacturing proc esses that will report under Subpart L are already regulated unde r one or more MACT standards. The recommendations below will strengthen the ultimate Subpart L.

Response: EPA appreciates the commenter’s support in its efforts to provid e flexible, accurate monitoring methods to facilities in the fluorinated gas production source category.

16Section 4.1 - GWPs not Available for all F GHG Compounds



### Commenter Name: Dave Stirpe


### Commenter Affiliation: Alliance for Responsible Atmospheric Policy


### Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number : 2

Comment: The Alliance believes that the definition of "fluorinated gas" is too vague. It leaves much uncertainty as to what is included. In order to provide clear direction· as to the fluorinated gases that are required to be reported, we request that EPA provide a positi ve specific list of the compounds upon which reporting is required. The lis t should include both the specific compound

and its GWP. GWPs that are not in the Fourth Assessment Report should be taken from a recent

credible scientific assessment report. Without a specific list, it appears th at there will be inconsistency in the reports since the defin ition will be interpreted differently among those required to report. Furthermore, many of the proposed requirements for in-process flow reporting

include chemicals for which GWPs have not been determined. Business and industry need certainty, and absent a list of covered com pounds and the EPA's accepted GWP, industry cannot determine with certainty whether it is in compliance with its reporting requirements. The publication of a specific list is consistent with existing regulations dealing with the reporting and handling of hazardous materials, including exis ting DOT regulations, existing EPA regulations for Tier I/Tier II reporting and fo r TRI Reporting. In any case when the chemical is not isolated, EPA should provide guidance on how su ch a chemical should be reported.

Response: EPA has designed the requirements of th e final rule to ensure consistency among fluorinated gas production facilitie s in how they monitor and re port emissions of fluorinated

GHGs that do not have GWPs listed in Table A-1 to subpart A. The definition of “fluorinated

GHG” rather than Table A-1 defines the set of fluorinated compounds th at facilities must monitor and report, and EPA has determined th at this definition provides sufficient clarity regarding the scope of the rule. Because facilities are not required to report CO 2 -equivalent emissions of fluorinated GHGs that do not have GWPs listed in Table A-1, differences in facilities’ evaluations of these gases’ GWPs will not affect the CO 2 -equivalent totals that they report. Where the rule requires a prel iminary assessment of emissions in CO 2 -equivalent terms, facilities are required to use a default GWP of 2,000 for GHGs for which GWPs are not listed in Table A-1, except in cases where the GWP of 2,000 would significantly overestimate the CO 2 e emissions from a continuous proces s vent and inappropriately trig ger emission testing. In these cases, facilities may submit a request to EP A to use a provisional GWP for emitted compounds that do not have GWPs listed in Table A-1. As pa rt of the process of reviewing the request, EPA will publish the proposed provisional GWPs and the information supporting them, providing an opportunity for public comment and ensuring that provisional GWPs are based on sound data and analysis and are consistently applied across facilities.

These issues are discussed in more detail in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Ga s Production (Subpart L)).

17

### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 6

Comment: §98.120 Definition of the s ource category. Not all compounds used in fluorinatedGHG production are listed in Tabl e A-1 and few if any of 3M’s vent streams will contain only Table A-1 compounds. While the rule provides a mass-based threshold in these cases, significant measurement and reporting obligations will be required for sources that emit low GWP materials. An example from one of 3M ’s manufacturing facilities is provided in

Attachment 1. Another issue concerns the RSD re quirements that are liste d in the rule. Meetingthese requirements for each chemical will be problematic. We recommend that GHG’s for nonTable A-1 compounds be determined using the met hods described and referenced in Section 2.10 of the Intergovernmental Panel on Climate Change Fourth Assessment report (IPCC AR4). Allowing such calculations would be mutually bene ficial to all stakehol ders. The process would generate important information th at could be used by the agency in evaluating the inventory data. The agency will need to complete this work as pa rt of its evaluation of inventory data, and it will very likely use similar methods. 3M and other co mpanies in this source category have already completed much of this work. Emission estimate s would still be required and reported for these locations along with any GWP calculations. The specific reference for the GWP calculations in

section 2.10 of IPCC AR4 is th e methodology of Pinnock et al. 1 Furthermore, an Excel implementation is also available. 2 For short-lived GHGs, i.e., lifetimes less than one week, the

methods listed in the IPCC will overestimate the GWP as these compounds are not well mixed in the atmosphere. In this case, modeling the tran sport of the fluorochemicals using a suitable chemical transport model provides a more accura te GWP value. This method is described by

Acerboni et al. 3 who observed that the radiative forcing was 8 to 23 times lower for short-lived perfluorinated alkenes using the chemical tran sport model versus the well-mixed assumptions

that is referenced in Pinnock. This reference al so contains GWP values that are not currently

contained in Table A- 1.

Response: Please see section II.E.3 of the preamble to this rule and the response to comment EPA-HQ-OAR-2009-0927-0117.1, excerpt 2.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 16

1 Pinnock, S.; Hurley, M. D.; Shine, K. P.; Wallington, T. J.; Smyth, T. J., Radiative forcing of climate by hydrochlorofluorocarbons and hydrofluorocarbons. Journal of Geophysical Research 1995, 100, (D11), pp. 23227- 23238).

2 Elrod, M. J., Greenhouse Warming Potentials from the Infrared Spectroscopy of Atmospheric Gases. (Journal of Chemical Education 1999, 76, (12), pp. 1702-1705.

3 Acerboni, G., Beukes, J.A., Jensen, N.R., Hjorth, J., M yhre, G., Nielsen, C.J., Sundet, J.K., Atmospheric degradation and global warming potentials of three perfluoralkenes,” Atmospheric Environment (2001) 35: 4113-

4123.

18Comment: Subpart L needs to allo w calculation of GWP for F GHG chemicals not listed on Table A-1. EPA: §98.123(a). Fo r a number of processes, th e emissions of FGHG products, byproducts, and waste compounds do not have a GWP factor and therefore the facility cannot

calculate the absolute error in units of CO 2 e. Comment: EPA needs to provide an option to calculate a compound’s GWP incl uding those consistent with internationally recognized protocols. This option should also be allowable to determine faci lity applicability in section 98.121, and for determining the appropriate emission factor methodology in section 98.123(b)(2)(A). By conservatively assuming fl uorinated compounds without an established GWP have a GWP on the order of 10,000 makes the a pplicability of this re gulation significantly more probable on fluorinated compounds that have been previously qualitatively determined (based the compound’s volatility, use, atmospheri c lifetime, volume etc) to not be a global warming compound of concern. These substances w ould include those that are used exclusively as reactive intermediates in the production of other chemicals of commerce. Generally, such substances are consumed entirely in the production process, are not released to the atmosphere

and do not contribute to climate change. Other substances are pr oduced in significant volume but because of their low vapor pressure, short atmos pheric lifetimes (less than 1 year) and modest GWP (less than 50) produce an insignificant co ntribution to greenhouse forcing when compared to existing high production volume fluorinated gase s. It is not only unreas onable, but is also inappropriate to shift the primary impact of the regulation by a ssigning a 10,000 GWP to all fluorinated organics with a vapor pressure greater than 1 mm Hg that do not have a Table I-A GWP. Allowing GWP calculation methodologies including internationally accepted GWP calculation methodologies will better focus the chem ical industry’s limited financial resources to

assess CO 2 e emissions of any significance. A reco mmended scientific methodology is provided in Appendix A.

Response: Please see section II.E.3 of the preamble to this rule and the response to comment EPA-HQ-OAR-2009-0927-0117.1, excerpt 2.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 20

Comment: We believe it is important for EPA to allow facilities to calculate a compound’s Global Warming Potential (GWP) consistent with internationally recognized protocols when it is

not included on Table A-1 of the rule. This would he lp a facility determine rule applicability in §98.121, and determine the appropriate emission factor methodology in §98.123(b)(2)(A). As detailed on page 18674 of the preamble, EPA notes that it is “making the reasonably conservative assumption that the unknown fluorin ated GHG could have a GWP of 10,000.” This assumption by EPA makes this regulation mo re onerous on fluorinated compounds that previously have not been considered in this rulemaking. These substances would include those that are produced in substantial volume but are used ex clusively as reactive intermediates in the production of other chemicals of commerce. Generall y, such substances are consumed entirely in the production process, are not re leased to the atmosphere and do not contribute to climate

19change. Other substances are produced in sign ificant volume, but due to their low vapor pressure, short atmospheric lifet imes (less than 1 year) and m odest GWP (less than 50), produce an insignificant cont ribution to GHG emissions when compared to existing high production volume fluorinated gasses. By arbitrarily and unreasonably assigning a 10,000 GWP to all fluorinated organics with a vapor pressure greater than 1 mm H g, EPA is placing an enormous burden on fluorinated GHG compounds that are not the central focus of the rule. Allowing

facilities to utilize GWP calcu lation methodologies, including in ternationally accepted GWP calculation methodologies, will better focus the chemical industry’s resources to assess CO 2 e emissions of significance. A recommended scie ntific methodology following IPCC guidelines is provided in Appendix A.

Response: Please see section II.E.3 of the preamble to this rule and the response to comment EPA-HQ-OAR-2009-0927-0117.1, excerpt 2 for a response to this comment.



### Commenter Name: Joel R. Hall


### Commenter Affiliation: Mexichem Fluor Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 10

Comment: The agency needs to provide a means to calculate a compound’s Global Warming Potential (GWP) for compounds not listed in Table A-1. Table A-1 to Subpart A of Part 98 lists Global Warming Potentials for a number of ch emical compounds. However, the table is not exhaustive and compounds not list ed could be considered by-pr oducts and therefore subject to reporting. Lack of a specified means to calcu late an unlisted compound’s GWP will lead to inconsistencies among regulated entities.

Response: Please see section II.E.3 of the preamble to this rule and the response to comment EPA-HQ-OAR-2009-0927-0117.1, excerpt 2.

Section 4.2 - Mass Balance Calculations



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 15

Comment: Second, EPA does not convi ncingly explain why it uses a monthly frequency for mass-balance reporting. EPA suggests that dail y measurements may be highly variable, 4 but these variations would be smoothed by averagin g daily values, and so do not provide much support for reducing monitoring frequencies. To th e contrary, as EPA itsel f explains, “[w]here mass flows and concentrations are variable, more frequent measurements and calculations will

4 See, e.g., 75 Fed. Reg. at 18,675.

20lead to more accurate and precise estimates than less frequent measurements and calculations.” 5
EPA’s only salient objection on th is point is that less freque nt sampling may help improve worker safety by reducing the need to test some corrosive or hazardous emissions streams. EPA is right to take this concern seriously, but it needs to document it more carefully, showing where these streams are, and whether or not technical ch anges may allow them to be measured safely. If

measurements can be taken on some or most stre ams more frequently without creating additional worker safety risks, they s hould be. EPA should, at a minimu m, strongly consider weekly reporting for all streams, unless worker safety concerns makes such reporting inappropriate for some specific emissions source. Fine-grained data is critical, especially where, as here, an emissions source is both highly variable and has high GWP gases, such that emissions on a single day may be quite significant.

Response: In response to this comment, and also in response to comments that raised questions regarding the treatment of multiple measurements in the error calculation in the mass-balance approach, EPA has clarified in the final rule th at process variability a nd measurement frequency

must be considered in the error calculation. Specifically, variabil ity in stream concentrations and the frequency of concentration meas urements must be considered.

As discussed in the Technical Support Document in the context of emission testing, the more variable a parameter is, the more samples must be taken to precisely characterize the mean of that parameter. The number of samples required to estimate the mean of the parameter with a given level of confidence can be calculated base d on the relative standard deviation (RSD) of the samples and on some assumptions about the dist ribution of the parameter. Where the set of samples is relatively small and only the sample standard deviation “s” is known (rather than the true standard deviation of the pa rameter), the appropriate statistic is often the Student’s t test.

Monthly sampling will generate twelve concentration measurements per stream per year. If the variability among the concentra tion measurements is high enough that these 12 measurements per year (i.e., monthly measuremen ts) result in relative and absolute errors above the 30-percent and 3,000-mtCO 2 e limits, based on the Student’s t test, then the facility must increase the frequency of its measurements if it wishes to us e the mass balance approach for the process. For example, facilities may find that weekly measurem ents are necessary to m eet the error criteria for certain processes. By including process variab ility in the error calcul ation, the rule ensures that more frequent measurements will be made if this is necessary to address process variability,

but it limits the costs and risks of sampling for processes where less frequent measurements yield precise results.

In addition to clarifying that pro cess variability must be considered in the error calculation of the mass balance approach, EPA is also requiring that facilities that use the alternative to the error calculation (the precision and accuracy requirements at §98.124(b)(8)) make weekly

measurements and calculations. EPA calculates th at at a weekly frequency, these measurements will lead to reasonably accurate emission estimate s (with an error near 30 percent) even if the concentrations in the process are highly variab le (e.g., even if the RS D of the concentration measurements is 50 percent, wh ich would be unusually high.)

5 Id.

21Two other requirements in the rule also addr ess process variability. First, under the mass balance approach, facilities are required to make concentrations measurements that reflect the full range of conditions within the process, e.g., ca talyst age. Facilities are also required to account for emissions that occur during process startups, shutdowns, and malfunctions, either recording fluorinated GHG emissions during these events or documenting that these events do not result in significant emissions . Together, these requirement s limit the impact of sampling

bias on emissions estimates. Please see section II.E.3 of the preamble to this rule for more discussion of the issue of process variability.



### Commenter Name: Dave Stirpe


### Commenter Affiliation: Alliance for Responsible Atmospheric Policy


### Comment Number: EPA-HQ-OAR-2009-0927- 0117.1 Comment Excerpt Number : 8

Comment: A substantial concern during the 2009 proposal pro cess was the original mass balance approach. The current proposal remove d many of the complexities of the 2009 draft Subpart L, including unachievable material meas urement, accuracy, and calibration standards. EPA appropriately proposed monthly mass balan ce calculations, instead of daily mass balance

determinations in 2009.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0128.1, excerpt 15.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 46

Comment: Monthly mass balance monitoring, as proposed at §98.124(b), is appropriate. Monthly mass balance data smoothes out daily mass balance variances that obscure actual operating trends.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0128.1, excerpt 15.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 11

Comment: Section 98.124(b) states “If you determine fluorinat ed GHG emissions using the mass balance method under §98.123(a), you must estimate the total mass of each fluorinated

22GHG emitted from the process at least monthly.” DuPont supports a monthly calculation, as compared to the April 2009 pr oposal of weekly calculations.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0128.1, excerpt 15.



### Commenter Name: Ross Smith


### Commenter Affiliation: PCS Phosphate Company, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0084.1 Comment Excerpt Number : 4

Comment: Under the current proposal, EPA is c onsidering allowing a mass balance approach for processes which meet an error estimation qua ntity limitation. The error estimation is made up of a complex set of requirements. A significant am ount of effort would have to be dedicated to determining if a facility could utilize the mass balance approach. Should the analysis yield that the facility cannot use this approach, these efforts would be wasted and the facility would be required to develop process specific emissions factors. Rather than forcing facilities to determine whether or not they can meet the requirement, the rule should be revised so that facilities which

emit emissions less than a set threshold could utilize the mass balance approach, while those above the threshold must comply using the other proposed method. Additionally, the development of process specific emissions factors, or the use of engineer ing estimates, could be

less accurate than th e error threshold of 30 percent or 3,000 mt CO 2 e required for the mass balance approach.

Response: In response to this and other comments regarding the complexity of the mass-balance error calculation, EPA is including in the final rule an alternativ e set of requirements that are designed to ensure that emission estimates de veloped using the mass-balance approach are reasonably accurate and precise. Under this alternative set of requirements, which can only be used for processes that have a total annual thr oughput of 500,000 mtCO 2 e or less of fluorinated GHG reactants, products, and by-products, facilit ies are required to measure the masses identified in the rule with an accuracy and prec ision of ±0.2 percent of full scale or better, to

measure the concentrations identi fied in the rule using analytic al methods with an accuracy and precision of ±10 percent or better, and to conduct these measurements at least weekly.

These requirements have been developed in cons ideration of the five factors that affect the absolute accuracy and precision of mass-bala nce estimates: (1) the relative accuracy and precision of the mass measurements, (2) the relativ e accuracy and precision of the methods used to measure concentrations (irrespective of pro cess variability), (3) proc ess variability, (4) the frequency of the measurements, and (5) the qu antity of the fluorinated GHG throughput of the process, that is, the total ma sses of the fluorinated GHG reactan ts, products, and by-products fed into and generated by the process. After considering multiple scenarios, EPA has concluded that the required accuracies, precisions, and fr equencies for the mass and concentration measurements, in combination with the 500,000 mtCO 2 e throughput limit, represent a reasonable

23means of achieving absolute e rrors near or below 3,000 mtCO 2 e. 6 The 3,000 mtCO 2 e absolute

error was identified as the limit because it is cons istent with the absolute error limit in the error calculation approach, which is discussed further below.

Although some of the requirements could be relaxe d and still result in an error near or below 3,000 mtCO 2 e, this would require a tightening of the other requirements. For example, if the requirements for the precision and accuracy of the mass measurements were relaxed to ±0.4 percent, the requirements for the precision and accuracy of the concentration measurements would have to be tightened, e.g., to ±5 percent, and the frequency of these measurements would

have to be increased. Based on comments received on the April 10, 2009 and April 12, 2010 proposed rules, EPA understands that achieving precisions and accuracies of ±5 percent for concentration measurements, and conducting these measurements more often than weekly, could be quite challenging. On the othe r hand, EPA believes that a number of facilities and processes are likely to be able to meet the alternative requirements in th e final rule. The precision and accuracy requirements for concentrations and for the frequency of measurement are less stringent than those initially proposed in the April 10, 2009 rule; those fo r masses are the same as those initially proposed.

While this alternative approach (to limiting the erro r), in itself, limits flexibility, facilities that

cannot or choose not to meet th ese requirements remain free to use the error calculation to demonstrate compliance with the mass-balance error limits. Under the error calculation, facilities have the flexibility to focus on improving the accuracy and precision of those measurements that have a signifi cant impact on the overall error of the estimate rather than expending resources to improve the accuracy and precision of measurements that are not as important to the accuracy and precision of the em issions estimate. EPA is planning to make a calculation tool available to facilities to help th em to calculate the error associated with use of the mass-balance approach. Facilities are also, of course, free to use the emission factor method (or, where appropriate, the emission calculati on factor method) to estimate emissions.

Under the error limit approach, facilities must de monstrate that the resu lting estimate will have a relative error no larger than 30 percent or an absolute error no larger than 3,000 mtCO 2 e. As noted in the April 12, 2010 proposed rule, these limits address th e fact that the mass-balance approach can have large errors because it is calculated as the difference between two large quantities, the inputs and the outpu ts of the process. However, the absolute erro r limit provides more flexibility than the relativ e error limit would by itself. Specifically, it allows use of the mass-balance approach with processes that have low emissions but that cannot meet the relative error limit. It would, for example, allow use of the mass-balance approach with a process with estimated emissions of 6,000 mtCO 2 e and a relative error of 50 per cent, because such a process would (just) meet the absolu te error lim it of 3,000 mtCO 2 e. This is consistent with our approach elsewhere in the rule, where we are allowing use of somewhat less precise methods for smaller emission sources. Nevertheless, to ensure that the estimates for smaller emission sources remain reasonably accurate, we are not simply adopti ng an emission limit below which the mass-balance approach can be used. This is because a proces s with small estimated emissions could still have

6 At an emission rate of two percent, the 500,000-mtCO 2 e throughput limit would result in emissions of 10,000

mtCO 2 e. The throughput, in combination with the precision, accuracy , and frequency requirements for measurements, would be expected to result in a maximum absolute error of 3,000 mtCO 2 e.

24a high absolute error, meaning that use of the mass-balance approach would lead to an unacceptably uncertain emission estimate. For exam ple, if a process had estimated emissions of 6,000 mtCO 2 e, but the relative error associated with using the mass-balance approach to estimate these emissions was 150 percent, then the absolu te uncertainty of the estimate would be 9,000

mtCO 2 e. In this case, there would be a signific ant probability that the process had actual emissions of over 10,000 mtCO 2 e. Thus, to obtain reasonably accurate process-level and facility-wide emission estimates, it is critical that facilities interested in using the mass-balance approach either calculate the rela tive and absolute errors associat ed with the use of the approach or comply with the alternative accuracy a nd precision requirements described above.

Again, this is consistent with EPA’s approach elsewhere in the rule. For continuous process vents that are estimated to emit more than 10,000 mtCO 2 e annually, facilities using the emission factor approach must develop an emission fa ctor based on emission testing. Based on the experience of companies that have developed emission factors based on emission testing, EPA

estimates that the relative error associated with using the emission factor approach is generally below 30 percent (as one half of a 95-percent conf idence interval). Although the error associated with using emission calculation factors (which are based on engineering calculations and assessments) may be higher, emission calculation factors may only be used to estimate emissions

from continuous vents whose emissions are estimated to fall below 10,000 mtCO 2 e. (As discussed in the preamble, we ar e allowing facilities to use em ission calculation factors for all batch processes regardless of size due to several t echnical issues that make it difficult to develop accurate emission factors for batch pro cess vents based on emission testing.)



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-106.1 Comment Excerpt Number : 21

Comment: In Section B.ii.2 of the Technical Su pport Document (TSD), EPA provides the Mass Balance approach equations. The mass of waste re moved from the production process in various streams (W Dj ) is always assumed to be ‘destroyed’ by a destruction device with percentage destruction efficiency. This statem ent appears to assume that the wa ste is a gas, or entrained in a gas stream, that is directed to a control device such as thermal oxidize r. Is this a correct interpretation?

Response: The stream would not necessarily have to be a gas or vapor. A stream that is recaptured to be destroyed could be a gas or vapo r or a liquid stream. There may be instances in which a stream to be destroyed is a liquid st ream that may be containerized, e.g., placed in

barrels or other containers and sent elsewhere fo r thermal destruction. The commenter refers to destroyed streams in the mass balance equations; the revised mass balance equations in the final rule include streams that are capture d for both destruction and recovery.

25Section 4.2.1 - Mass Balance Error Calculation



### Commenter Name: Joel R. Hall


### Commenter Affiliation: Mexichem Fluor Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 3

Comment: The error calculati ons used to determine if the ma ss balance approach can be used are onerous and confusing. Mexichem understands the need for a high degree of accuracy and precision for these measurements and that the error test is a means to drive affected entities to

obtain accurate data.

Mexichem also appreciates the fact that the agency provided us with an example workbook to show how the errors required to be calculated under the mass balance approach could be calculated for production of HCFC 22 with HFC 23 as a by-product. However, the workbook

assumes that the relative error associated w ith each measurement (including destruction efficiency) is known. In actuality, this will not likel y be the case. In addition, it is unclear when the “error test” must take place. The proposed rule states “before using the mass balance approach,” but as we understand the calculations , at least one measurement must be taken in order to perform the calculations. If measuremen ts used to calculate fluorinated GHG emissions are to be made monthly as indicated in §98.123(a)(7 ) then would the error ca lculations also need to be made monthly? Or should they be made annually when the total estimated emissions are determined? If they are to be made annually, ther e will be at least twelve data points for some measurements (e.g., reactant fed and removed, product produced, etc.). It is not clear how multiple measurements are to be handled in the e rror calculations and if a facility waited until the end of the year to perform the error test and “fa iled” it, they would not be able to estimate their emissions using either of the emission factor approaches unless they had assumed that they

would not meet the error test criteria early in the year a nd begun performing the tests, etc. required to estimate their emissions using one of the emission factor approaches.

Mexichem requests that the agency consider, for the mass balance approach, mandating the use of measuring equipment with an accuracy and pr ecision of one percent fu ll scale or better for measurement of the reactant fed into the proce ss that is used for the mass balance equation and fluorinated GHG product coming out of the proce ss coupled with emission factors or emission

characterization of uncontrolled process vents to control device s and an assumption that any

unaccounted fluorinated GHG is emitted as a fugitive.

The accuracy requirements under Subpart OO al ready require that fluorinated GHG product coming out of the process be measured using flowmeters, weigh scales, or a combination of volumetric and density facilities, many of which ar e likely measuring to this degree already. The

mass of fluorinated GHGs sent to a destructi on device could be determined using emissions

factors or emission characterizati on of uncontrolled process vents. As indicated in comment # 4 Mexichem would prefer that the emission factor s be determined by an engineering assessment rather than an extractive procedure due to the safety concerns associated with sampling HFcontaining streams. Yield loss and mass of by-product produced could be calculated based on

26engineering assessments. Equations L-7 and L-12 could then be used to calculate mass of fluorinated GHG product and by-product emitted from the process.

Response: Please see section II.E.3 of the preamble to this rule for a re sponse to the comments regarding the timing and cont ent of the error test.

As an alternative to the error test, EPA is includ ing in the final rule specific accuracy, precision, and frequency requirements for mass and concentration measurements. In combination with a process throughput limit, these requirements are designed to ensure that emission estimates developed using the mass-balance approach are reasonably accurate and precise. The accuracy and precision requirement for mass measurements under this alternative a pproach is ±0.2 percent of full scale. Please see the respons e to comment number EPA-HQ-OAR-2009-0927-0084.1, excerpt 4 for a discussion of thes e requirements and their rationale.

Regarding a requirement to use measurement equi pment with an accuracy and precision of one percent of full scale, EPA has concluded th at, under the mass-balance approach, such a requirement would result in emission estimates with high relative errors. For example, for one common process with an emission rate of two percen t, such a requirement c ould easily result in

an emission estimate with a relative error of over 70 percent. This is unacceptably high, particularly given that the relativ e error associated with using the emission factor approach is estimated to be under 30 percent.

The commenter suggests the possibility of using emission factors or emission characterizations to estimate the quantities of fluorinated GHGs se nt to the destruction device. The mass-balance approach being finalized requires facilitie s to measure the mass flows and fluorine

concentrations of streams flowi ng to destruction devices at leas t monthly. (Measurements must

be made more often if this is ne cessary to meet the error limit or to comply with the alternative to the error limit). If an element ot her than fluorine is used to estimate emissions, that element is required to be tracked instead. Fluorine concentr ations may be determined either by determining

the concentrations of individual fluorine-cont aining compounds in the stream and multiplying these concentrations by the mass fraction of fl uorine in each compound or by directly measuring the total fluorine in the stream, e.g., using AS TM D7359-08. Facilities that use the latter approach must also measure, at least once, the concentrations of the individual fluorinecontaining compounds in the destroyed stream. This is to allow the correct destruction efficiencies to be applied to the contents of th e stream, and to characterize the emissions of any fluorinated GHGs that survive the destruction pro cess. Emissions that cannot be accounted for at vents are assumed to occur through equipment leak s; and emissions from equipment leaks must be assigned the same chemical composition as the weighted average, pre-destruction composition of emissions from process vents.

For purposes of the mass-balance approach, EPA does not consider en gineering calculations, rather than measurements, to be adequate to estimating fluorine (or other element) flows into

destruction devices. Our concern is that the error associated w ith such an approach could be quite high. However, under the emission fact or approach, EPA now permits engineering

calculations to be used under a wider set of circumstances than in the April 12, 2010 proposed rule. Specifically, engineeri ng calculations may be used to estimate emissions from batch

27process vents. They can also be used to estima te emissions from continuous process vents where controlled emissions (rather than uncont rolled emissions, as proposed) fall under 10,000

mtCO 2 e, even if the destruction efficiency of th e destruction device fall s under 99.9 percent. In addition, where emission testing is required, facilities may conduct it after the destruction device in some situations. That is, facilities may esti mate a controlled emission factor by testing at the

outlet of the destruction device as long as the total emissions from the process vent that are not

routed to a destruction device (e.g., during bypass period s) are less than 10,000 mtCO 2 e. If there are periods during which the vent ’s emissions are not vented to the destruction device, the revised rule requires that, in addi tion to developing a controlled em ission factor, the facility also develop an emission calculation factor for the periods when the process vent is not vented to the

destruction device.

For process vent streams where the total “u ncontrolled” emissions are greater than 10,000

mtCO 2 e, facilities must conduct emission testing on the uncontrolled emissions. Additional flexibility has been added to the rule for uncont rolled streams as well. The final rule allows testing for emission factor development following a wet scrubber that is in place for acid gas removal, either HF or HCl, as long as there is no appreciable reduction of the fluorinated GHG.

We believe that by allowing (1) use of engin eering calculations in more situations, (2) development of controlled emissions factors, and (3) development of uncontrolled emission factors following a wet scrubber in place for acid gas control, the final rule will reduce the

number of situations in which facilities must measure streams that contain acid gas.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 13

Comment: Preamble and regulatory langua ge use of “or” and “and” ne ed to be consistent to avoid confusion. EPA: §98.123(a) in the Preambl e says that in order to use the mass balance approach "EPA would require that the error associated with the overall estimate of fluorinated GHG emissions fall under 30 percen t (relative error) OR under 3,000 mtCO 2 e (absolute error)” (emphasis added). Comment: The regulatory text is different from the Pr eamble text as written which appears inconsistent and confusing to the reader. EPA response when questioned about

this issue stated that Preamble and Rule text ar e just a positive and nega tive way of stating the requirement, and both are consistent. This is not obvious to reader and definitely needs

clarification in the final rule.

Response: EPA agrees that a clarification of the ru le text is appropriate. The rule text in §98.123(b)(1) that explains the e rror calculation criteria has b een revised to match the reproposal preamble text. While EPA notes that the preamble text and the rule text stated the identical criteria at re-proposal, the use of the “or” with “less th an” format in the preamble and the “and” with “greater than” format in the rule text proved to be confusing to commenters. The

text in the final rule is as follows: “You may use the mass-balance approach to estimate emissions from the process if this calculation results in an absolute error of less than or equal to

283,000 metric tons CO 2 e per year or a relative error of less than or equal to 30 percent of the

estimated emissions.”



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 11

Comment: We also request clarification on the allo wed errors associated with the mass balance approach because the language in the preamble and regulatory text appear to conflict. The regulatory text in §98.123(a) r eads “If this calculation shows that use of the mass-balance approach to estimate emissions from the proce ss will result in an absolute error exceeding 3,000

metric tons CO 2 e per year and a relative error exceeding 30 percent, then you cannot use the mass-balance approach to estimate emissions fr om the process.” (Emphasis added). However, the preamble explanation on page 18674 states that “EPA would require that the error associated

with the overall estimate of fluorinated GHG emi ssions fall under 30 percen t (relative error) or under 3,000 mtCO 2 e (absolute error).” (Emphasis added).

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 13.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 10

Comment: Section 98.123(a) states; “Before using the mass balan ce approach to estimate your

fluorinated GHG emissions from a process, you must estimate the ab solute and relative errors associated with using the mass balance approach...” We question the nece ssity of estimating the

absolute and relative errors a ssociated with using the mass balance method on a process, as detailed in the proposed rule. This type of analysis has not been required by any other EPA reporting rule. These equations are quite detail ed, and as such, incr ease the burden on the reporter. We have evaluated the proposed mass ba lance approach for a very simple process and discovered that this type of analysis is quite complex and is something that only a trained statistician is capable of performing. Process engi neers from two of our plant sites were not able to figure out how to use the proposed equations, and felt that a professi onal statistic ian or Six Sigma Black Belt would be needed. If EPA believe s this analysis is absolutely necessary, we recommend that EPA develop a statistical tool that is very user friendly, which will greatly assist affected sources in assessing the erro r bands around the mass balance approach.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0084.1, excerpt 4 for a discussion of an alternative set of requirements that facilities can meet to ensure that the emission estimates that they develop using the mass-balance a pproach are reasonably precise and accurate.

29

### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 10

Comment: Much of this section has not cha nged from the April 2009 proposed §98.123. We do support the change to a monthly calculation, instead of the April 2009 proposed weekly calculations. However, we question the necessity of estimating the absolute and relative errors associated with using the mass balance method on a process, as shown in equations L-1 through L-4. These equations are quite complex, and as such, increase th e reporting burden.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0084.1, excerpt 4 for a discussion of an alternative set of requirements that facilities can meet to ensure that the emission estimates that they develop using the mass-balance a pproach are reasonably precise and accurate.



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 25

Comment: Much of Section 98.123 has not change d from the proposed April 2009 language. We do support the change to a monthly calculati on, as compared to the April 2009 proposal of weekly calculations. However, we question the n ecessity of estimating the absolute and relative errors associated with using the mass balance method on a process, as shown in equations L-1 through L-4. These equations are quite comple x, and as such, increase the reporting burden.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0084.1, excerpt 4 for a discussion of an alternative set of requirements that facilities can meet to ensure that the emission estimates that they develop using the mass-balance a pproach are reasonably precise and accurate.



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 15

Comment: Initially, the mass-balance approach ri sks substantial uncerta inty. Because that approach requires facilities to derive relatively small leakage estimates from differences between the large masses of reactants used and products created, small errors in measurement can

translate into substantial varia tion in leakage estimates. EPA seek s to limit this uncertainty to a maximum relative error of 30%, but this is still a high value: It estimates, for instance, that the

30uncertainty of the more precise “process vent speci fic emission factor approa ch is anticipated to be roughly 10 percent.” 7 It is not at all clear why EPA is willing to tolerate the higher uncertainty associated with the mass-balance approach. We do not recommend that it do so in the final rule.

If EPA nonetheless retains this approach, it could improve it in several ways. First, EPA should consider specifying specific uncertainty limits fo r individual steps in the mass-balance process, in addition to setting a maximum uncertainty level. As the TSD explains, setting precise measurement requirements for tools like flow meters and scales “limits error and is straightforward to implement and enforce.” 8 It is, certainly, far bette r than EPA’s proposed rule, which would simply require facili ties to do several error estimati on calculations before using the mass-balance approach. 9 This requirement is very difficult to enforce: EPA cannot readily backcheck the assumptions on which such calculations are based, and so must largely take companyderived estimates on faith. EPA could, on the ot her hand, test to see whether equipment was calibrated according to proper standards. EPA s hould adopt such enforceable standards instead.

Response: EPA has concluded that use of the erro r calculation, which requires facilities to explicitly identify and consider the uncertainties associated with their measurements of masses and concentrations, including process variability, will ensure that emissions estimates developed using the mass-balance approach will be reasonab ly accurate and precise. Contrary to the

commenter’s assertion that “E PA cannot readily back-check the assumptions on which such calculations are based,” EPA will be able to ch eck these assumptions because facilities are required to report, at §98.126(b)(1), the absolute and relative uncertainties calculated for each process, including the quantities used in these calculations and their uncertainties. These

uncertainties will consist of the errors associ ated with mass and concentration measurements, i.e., the accuracy and precision of flowmeters an d analytical methods, and the variability of the process. These can be verified by inspecting equi pment or process records, if necessary. Under §98.127(c)(1), facilities are required to keep records of the data a nd calculations used to estimate

the absolute and relative errors . In addition, under §98.124(e)(3), facilities are required to document the analytical methods that they use to measure concentrations, including quantitative estimates of each method’s accuracy and precis ion for the analytes of interest at the concentrations of interest. Finally, under §98.12 7(i), facilities are required to keep records documenting the calibration of all the equipment that they use to measure masses and concentrations, including the industry standards or manufacturer directions used for calibration.

As discussed in the response to comment number EPA-HQ-OAR-2009-0927-0084.1, excerpt 4, EPA is including in the final rule an alternative set of requirements that facilities can meet to ensure that the emission estimates that they develop using the mass-balance approach are reasonably precise and accurate. However, these ar e intended to be used as an alternative to the error calculation for any given pr ocess, not along with it. If both the error and limit and the alternative set of precision and accu racy requirements were applied to the same process, the two sets of requirements would be redundant. The combination would add more complexity to the rule without increasing the precis ion or accuracy of the estimates.

7 75 Fed. Reg. at 18,678.

8 Fluorinated Gas TSD at 11.

9 Fluorinated Gas TSD at 11

31The commenter notes that the 30 percent relative error criterion for the ma ss balance appears less rigorous than the 10 percent error cited for the emissions factor appro ach. EPA would like to clarify that the 10 percent error that was cited for the emission factor in one part of the preamble to the re-proposed rule is a generally accepted uncertainty for the EPA reference methods for measuring concentrations. Thus, the 10 per cent uncertainty cited does not encompass the complete error associated with the emission factor approach. Specifically, the 10 percent uncertainty does not include the additional error in the “emission factor,” which includes the

uncertainties associated with the variability of the process (which can be significant) and with the measured process activity rate during the testing. As noted in the re-proposed rule, the uncertainty for fluorinated GHG emission factor s that was estimated by one facility was approximately ±25 percent (expressed as one half of a 95-percent confid ence interval); this estimate included process variability. Finally, ad ditional uncertainties are associated with the process activity level that is multiplied by the emi ssions factor to estimate actual emissions, and with estimates of emissions from equipment leak s (which do not need to be calculated under the mass balance approach). In summary, therefore, the 10 percent uncertainty does not encompass

the full error inherent in the emissions factor approach. EPA therefore believes that the 30- percent relative error limit for the mass-balance approach is comparable to the maximum error that is likely to be associated with estimates developed using the emissi on-factor based approach

for fluorinated GHG emissions fr om fluorinated gas production.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 14

Comment: The 3,000 mtn/yr CO 2 e error threshold should be increased to 10,000 mtn/yr CO 2 e. EPA: §98.123(a) states: “If this calculation sh ows that use of the mass-balance approach to estimate emissions from the process will result in an absolute error exceeding 3,000 metric tons

CO 2 e per year and a relative error exceeding 30 pe rcent, then you cannot use the mass-balance approach...” Comment: The absolute error bright-line of 3,000 CO 2 e is unrealistic. For an FGHG with only a GWP factor of 1000, this transl ates to only 3 mtn of mass, or 0.3 mtn mass using EPA’s default GWP factor of 10,000. For a pr ocess with small emissi ons, the relative error is likely to be high, and a GWP or mass emission threshold becomes critical. EPA needs to raise

the absolute error thre shold to 10,000 mtn/yr CO 2 e or greater.

Response: In the final rule, EPA is retaining the proposed maximum absolute error of 3,000

mtCO 2 e. As discussed in the proposed rule, th is error was developed by multiplying the 30- percent relative erro r limit by the 10,000 mtCO 2 e level used elsewhere in the rule as the level below which less rigorous emission estimati on methods are allowed (e.g., engineering

calculations rather than emissi on testing for developing emission calculation factors for vents). (The 30-percent relative error limit is discussed in the proposed rule and in the response to comment EPA-HQ-OAR-2009-0927-0128.1, excerpt 15.) This ensures general consistency

across the different estimation methods used in the rule in their treatment of smaller emission

sources.

32Please see the response to comment numb er EPA-HQ-OAR-2009-0927-0084.1, excerpt 4 for more discussion of the 3,000-mtCO 2 e absolute error limit and the large errors in emissions estimates that could result from eliminating or incr easing this limit. Note that in the final rule, facilities are required to use a default GWP of 2,000 rather than 10,000 in calculating the relative and absolute errors of their mass-balance estimates; this change is expected to increase the number of processes with which the mass-balance approach may be used.



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 18

Comment: In [section] B, Fluorinated Gas Pr oduction, Section 5.c [of the re-proposal preamble], EPA requests comment on th e absolute error limit of 3,000 mtCO 2 e, while noting that

EPA is also consideri ng a higher limit of 5,000 mtCO 2 e. Air Products supports a higher limit for the absolute error that approaches the rule reporting threshold of 25,000 mtCO 2 e.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 14.

Section 4.2.1.2 - Set error limit as a percentage of reactants or products



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 15

Comment: The mass balance error estimates need to be based on mass of reactants or products. EPA: On page 18675 of the Subpart L preamble, EP A states “Another approach that would avoid penalizing facilities with low emission rates woul d be to express the maximum relative error as a

fraction of the total mass of reactants fed into (or consumed by) the process.” Comment: We also strongly agree with EPA’s statement that in fact, the proposed mass balance method does penalize F-GHG processes that have low emissions . We evaluated an F-Gas process that had extremely accurate measurements of reactants a nd products, and fairly accurate measurements of waste streams. The resulting relative error wa s over 200%, when based on its very small amount of emissions. However, when the alternate method suggested by EPA in the Preamble (p.18675) was evaluated, the relative error was only 15%. Th erefore, we recommend that EPA provide this

alternate method of relative error calculation as an option in the rule and also as part of the statistical tool to help sources comply with this complex reporting rule.

Response: A response has been provided in secti on II.E.3 of the preamble to this rule (section II.E, Fluorinated Gas Production (Subpart L)).

33

### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 19

Comment: In [section] B. Fluorinated Gas Produc tion, Section 5.c. [of the TSD], EPA requests comment on another approach to absolute error th at expresses the maximum relative error as a fraction of the total mass of reactants fed into the process. Air Products s upports this alternative relative error approach for the Ma ss Balance emissions approach.

Response: A response has been provided in section II. E.3 of the preamble to this rule (section II.E, Fluorinated Gas Pr oduction (Subpart L)).



### Commenter Name: Joel R. Hall


### Commenter Affiliation: Mexichem Fluor Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 2

Comment: Mexichem supports the option to use cons umption of one of the reactants (e.g., HF or a chlorocarbon reactant) in determining em issions of fluorinated greenhouse gases from production processes under the mass balance approach.

However, we question the need to report the tota l mass of each reactant fed into and permanently removed from the production proces s (see §98.126(b)(3) and (4)). If Mexichem is able to use the mass balance approach, it’s emission calculations will be based on the amount of chlorocarbon reactant used because HF is used for other purposes in the production process, such as catalyst treatment. Therefore, for Mexichem’s producti on process, the amount of HF fed into the production process will not provide an indi cation of fluorinated GHG product produced. Attempts to measure the amount of HF perman ently removed from the process will result in unnecessary burden. If the agency is going to use reactant data and yield loss as a means to verify or check reported fluorinated GHG producti on, the mass of the reactant used for the mass balance equation and a balanced chemical equation will suffice.

Response: To allow use of the mass-balance appro ach with transformation processes and other processes in which fluorinated GHGs are not the product, EPA has revised the mass balance approach to track total fluorine or another element, as long as that element occurs in all of the fluorinated GHGs fed into or generated by the pro cess. The equations are written using fluorine as the default element, but the Agency is allo wing facilities to adapt the equations, monitoring, reporting, and recordkeeping requirements to anot her element as necessary. In the final rule, facilities are not required to report reactants that do not contain the tracked element.

Section 4.2.3 - Allow Alternative MB A pproach for Transformation Processes



### Commenter Name: Jeff C. Muffat

34

### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 7

Comment: §98.123 and §98.123 (a), Calculating GHG em issions. The mass balance method that is described in §98.123 (a ) precludes the use of this approach for certain production

activities. It could not be used for transformations that produce materials other than fluorinated

GHGs and isolated intermediates where reactions which produce fluorinated GHGs do not take place. Under the current rule language, transf ormations which do not produce fluorinated-GHG

must use one of the emission calculation factor me thods specified in §98.123 (b ), (c), or (d). In addition, the two fundamental mass balance equations, Equations L-7 and L-12, are not

structured so as to accommodate transformations or other process activ ities where fluorinated GHGs are not produced with reactions. In the re -proposed Subpart L rule, EPA introduced the concept of the “isolated intermedia te.” 3M believes that the “isolated intermediate concept” is an appropriate methodology for managing emission factors in this very diverse and complex source category. However there are many processes where reactions do not occur. This will include simple distillation processes, filtration steps, and packaging operations. While it is still

not clear whether this method will be used in any of 3M’s manufacturing operations, we believe

that it will be most feasible for those operations described in the previous sentence. In these cases, there may be only a limited number of individual process st reams to measure which could improve the utility, cost effectiveness, and accur acy of the emission estimate. 3M believes that the equations could be easily modified so as to replace the Equation L-7 expression, (R*MWP*SCP)/(MWR*SCR), with a term which e xpresses the mass of product being fed into the process, e.g., P IN . In the case of E quation L-12, the term B kip could be placed with a term that describes any by-products th at were produced in an upstream process, e.g., B in . For transformations, it is likely that separate equa tions would be required. In addition, we believe that it may be appropriate to allow for the ma ss balance approach for a group of isolated intermediates. There may be cases where a faci lity would wish to conduct an evaluation on a group of processes which consist of several isol ated intermediates. This approach would be somewhat consistent with what EPA proposed in the original Subpart L in April of 2009. The calculations provided in the exis ting rule would be adequate to reflect the combination of a number of processes.

Response: EPA agrees that facilities should be provi ded with the option to use the mass-balance approach for transformation processes, and the requirement that faci lities apply only the emission factor or emission calculation factor ap proach to transformation processes has been

removed from the final rule. The mass balance a pproach has been revised to a total fluorine mass balance approach that encompasses not only transformation processes but also processes

where no reaction occurs. Rather than assi gning any missing mass in the mass balance to product emissions as was required under the re -proposal mass balance option, facilities are required to use emission measurements to assign missing mass to reacta nt, by-product, and/or product emissions, as appropriate. Alternatively, they may assume that all emissions of fluorine

occur in the form of the fluor inated GHG that has the highest GWP among the fluorinated GHGs

that occur in more than trace concentrations in the process. Under the revised mass balance approach, facilities would conduct a mass balance on total fluorine and account for all fluorine in to the process and all fluorine out of the process, and determine the total fluorine emitted. The

35facility would then determine what fraction ofthe total fluorine is emitted as reactant, byproducts, or product by conducting em ission characterizations for process vents by measurement to speciate the total fluorine. For larger processes with emissi ons equal to or greater than 25,000

mt CO 2 e, facilities would be require d to conduct measurements for certain large process vents, use existing measurements for other process ve nts, and make assumptions about fugitive

emissions based on the contents of vented emissions.

Revisions to the mass balance approach have been made to allow this approach for non-reaction processes, e.g., for distillation processes or filtration processes. Rather than accounting for only the “reactant” or the “product,” the equations now incorporate account ing for “inputs” and “outputs” for processes where ther e is not a chemical reaction. In general, any fluorinated GHG production processes and transformation proces ses that have accur acy and precision for

measurements that allow the error criteria to be met may use the mass balance approach.



### Commenter Affiliation: 3M Center


### Commenter Name: Jeff C. Muffat


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 21

Comment: While we do not anticipate widespread us e of the material balance approach in our facilities, we are requesting that it be made available to certai n transformations and chemical operations that do not involve reactions.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 7.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 12

Comment: §98.123 inappropriately limits the use of mass balance fo r transformation processes. EPA: Section 98.123 states “...For processes that manufacture CFCs or HCFCs or that transform fluorinated gases into substances other than fluorinated GHGs, you must use the procedure in paragraphs (b), (c) and (d) of the section”. Comment: This section restricts the use of mass balance for processes that transform FGHG raw mate rials to non-FGHG products. The mass balance method in the proposed rule does not allow it to be used for transformation processes that do not produce an FGHG. EPA st ates that the reason for this is because transformation processes are not required to have the measurem ent accuracy of FGHG reactants and products. Some transformation processes al ready measure reactant s and products with sufficient accuracy to qualify for using the ma ss balance approach. Therefore, we believe EPA needs to provide sources with the option to use mass balance approach if the process measures transformed products with the required accura cy of FGHGs. Also, the equations for mass balance assume that any missing mass is th e FGHG product. Missing mass is typically a

36combination of one or more react ants, the final product, waste streams, and by-products. This is a worthwhile simplification, but is likely to overestimate emissions.

The regulation should be rewritten to allow a source the option to use plant knowledge and engineering calculations to dete rmine the portion of missing mass th at is FGHG, and if it is an emission. This would be mandatory if the produc t(s) were not an FGHG and the mass balance approach were employed.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 7.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 12

Comment: This section does not allo w the use of the mass balance method for processes that

transform fluorinated GHG raw materials to non-fluorinated GHG products. Because the emission estimation methodology for transformati on process is not defi ned in subpart L, facilities are forced to use the emission factor approach. The mass balance alternative for all transformations should be included, and this provision should be incorporated into §98.124(b)(1)(i) to require use of compliant monito ring devices for all fluorinated products if using the mass balance alternative. In fact, th e mass balance equation should be modified to include all fluorinated GHG processe s, not just those that involve reactions. This would include various chemical manufacturing processes where simple distill ations or purifications are conducted to produce an isolated intermediate. EPA should also allow for the use of a single mass balance approach on a group of isolated in termediates. This would be appropriate for a process which involves an isolated intermediate which is manufactured, stored, and subsequently purified in a separate step.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 7.

Section 4.3 - Emission Factor and Em ission Calculation Factor Methods



### Commenter Name: Dave Stirpe


### Commenter Affiliation: Alliance for Responsible Atmospheric Policy


### Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number : 9

Comment: EPA appropriately provide s reporting facilities the opti on to modify the existing emission factor compliance system that many fluorochemical manuf acturers use today to demonstrate compliance with a variety of Clean Ai r Act obligations. Subpart L facilities comply

with several Maximum Achievable Control Technology (MACT) standards in 40 CFR 63. The

37emission factor approach proposed in the new Subpart L will allow reporting facilities to adapt their existing reporting systems to meet Part 98 reporting obligati ons in the most efficient and consistent manner possible.

Response: EPA appreciates the commenter’s support fo r its efforts to provide flexible, accurate monitoring methods to facilities in the fluorinated gas production source category.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 13

Comment: We support EPA’s inclusion of the emi ssion factor and emission calculation factor methods in this proposal, as we noted in our June 2009 comments on this subpart.

Response: EPA appreciates the commenter’s support fo r its efforts to provide flexible, accurate monitoring methods to facilities in the fluorinated gas production source category.

Section 4.3.1 - Preliminary Estimate of Emissions by Process Vent



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 11

Comment: EPA should clarify propos ed §98.123(b)(1), or provide a note in a final Subpart L preamble, that process simulation models, such as ASPEN® by Aspen Technologies Inc., satisfy engineering calculations requireme nts for Subpart L process evalua tions. At first appearances, this proposed provision seems to infer that §98.123(b)(1)(i) describes typical batch emission calculation methods, and §98.123(b)(1)(ii), Engi neering Assessments, describes typical continuous process emission determination methods. At 75 Fed. Reg. 18679/1, EPA describes common batch emissions calculation examples for where engineering calculations describe emissions. EPA describes the variety of batch em issions events in this preamble, but does not describe common continuous proce ss vent activities. We have learned from EPA that this batch

versus continuous distinction was not intended. One method to allevi ate this interpretation is for EPA to clarify that continuous process models, su ch as ASPEN, are suitable to satisfy proposed §98.123(b)(1)(i), and that bench scale models ma y be used for either continuous or batch

processes.

Response: As discussed in the preamble of the fina l rule, we are not requiring that facilities perform a preliminary calculation of emissions fr om batch process vents; instead, facilities are allowed to develop emission calculation factors based on engineering calculations or assessments for all batch process vents, re gardless of emissions. However, for purposes of performing preliminary calculations for continuous process vents, and for purposes of developing emission

38calculation factors for either c ontinuous or batch process vent s, we have clarified that engineering calculations and engi neering assessments may be used for both batch and continuous process vents, using the methods described in §98.123(c)(1)(i) and (ii) [formerly §98.123(b)(1)(i) and (ii) in the April, 2010 proposed rule], as appropriate. The engine ering calculations noted

include the batch calculation methods in the Emission Inventory Improvement Program (EIIP),

batch emission calculations from the Miscella neous Organic NESHAP, and use of commercial software products. Engineering assessments can be based on multiple types of approaches, as included in the engineering assessment para graph (§98.123(c)(1)(ii)). The engineering calculations and the engineering assessments are available for preliminary emissions estimates for batch and continuous processes. The equa tions focus on batch operations; however, they could be used for continuous processes to the ex tent they are applicable. For example, if a continuous process included a reaction that generated a fluorinated GHG byproduct that is vented at some point, then the ga s evolution equation would be appl icable for that process. The other available options, both use of commercial software products and engineering assessments, are available for continuous processes but may be used for estimating emissions from batch processes as well, to the extent applicable. For example, if a f acility has previous measurement data or test results on a batch process, these ma y be used to estimate emissions from the process

or to inform the batch calculations. Because the available approaches include use of commercial software products, use of the ASPEN process simulation models mentioned by the commenter would be appropriate and allowed. Other soft ware products, such as WATER9, may also be used in applications to estimate fluorinated GHGs from process vents. Facilities are required to keep records of the data and cal culations used to develop their preliminary estimate of emissions for each process vent; they should have records ava ilable and be able to explain how their use of a particular emissions estimation method fo r a particular vent is appropriate.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 9

Comment: Arkema appreciates EPA proposing the Engineering Assessment process as a screening step to rationa lize emission source testing later in Subpart L. EPA should clarify that reporters evaluating continuous processes begin their analysis at §98.123(b)(1)(ii). EPA should also clarify that existing process vent characte rization data that substantially documents the Engineering Assessment paramete rs satisfy this provision.

Response: EPA appreciates the commenter’s support in its efforts to provid e flexible, accurate monitoring methods to facilities in the fluorinated gas production source category.

With respect to requirements for continuous pr ocess vents, please see the response to comment number EPA-HQ-OAR-2009- 0927-0085.1, excerpt 11.

EPA agrees that existing process vent charact erization data for the engineering assessment satisfies the provision, if the exis ting data are representative of the current operating scenario of the process. These data the commenter menti ons would be comparable to requirements in

39§98.123(c)(1)(ii) for engineering assessments.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 12

Comment: Other common process calculation me thods, such as EPA WATER9 wastewater emissions models, may be appropriate to calculat e emissions from some fluorinated gas process operations. EPA should confirm that any emissi ons model appropriate for process emission calculations may meet the §98.123(b) (i)(C) “[c]ommercial softwa re products that follow chemical engineering principles” definiti on. Reporters should document these emission calculation methodologies in their Subpart A GHG Monitoring plans.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 11.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 23

Comment: The § 98.123(b)(i)(B)(4)(iii) requirement to perform a material balance for each component in any batch manufacturing system employing condenser emission controls is unnecessary. This requirements seems to stem from § 63.1257(d)(3)(iii)(B), where a facility operating a condenser as a batch emission control device may eith er perform a material balance across the condenser system or show that the material in the underlying vessel is not boiling. Furthermore, this §63.1257 condition only applies wh en the condenser is the last control device in a control device system. EPA has not explaine d why forcing facilities to perform material balances for each component in a condenser control device system is necessary. Facilities subject to this subpart already comp ly with the underlying §63.1257 requirements, and may need to change their underlying MACT co mpliance programs, or comply with both portions of the MACT control requirements, to meet Part 98 conditions. The Climate Change Reporting Rule should not require duplicative compliance re quirements. EPA should delete proposed §98.123(b)[1](i)(B)( 4 )( iii ) in deference to §63.1257(d)(3)(i ii)(B).

Response: As discussed in the preamble of the fina l rule, we are not requiring that facilities perform a preliminary calculati on of emissions from batch pro cesses; instead, facilities are allowed to develop an emission calculation f actor based on engineering calculations or assessments for all batch processes, regardless of size. To devel op emission calculation factors, facilities must follow the equations and process condenser definition consistent with 40 CFR 63, subpart FFFF, Miscellaneous Organic NESHAP. With respect to §63.125 7(d)(3)(iii)(B), the Miscellaneous Organic NESHAP re quirements do not point to this paragraph of the 40 CFR 63, subpart GGG, Pharmaceuticals NESHAP. Because the subpart L requirements include the

40process condenser definition from the Miscellane ous Organic NESHAP, use of the terms process condenser and air pollution control device cond enser in §63.1257(d)(3)(iii) (B) would not match the definitions for subpart L. Under the MON process condenser defini tion, a facility would likely not be able to demonstrate 99 percent e fficiency for many process condensers, and the requirement in §63.1257(d)(3)(iii)(B) for demonstrating that the exit gas temperature is less than the boiling or bubble point is based on the premise of the Pharmaceutical process condenser definition; part of the Pharmaceutical process condenser definition is that the liquid in the process vessel must be above the boiling or bubble point. (In the case wh ere a process vessel is heated but not boiling, and vapors from the vessel are recovered in a cond enser, this condenser would technically be a control condenser under Pharmaceuticals, although it could be a process condenser under the MON). The requirement in §63.1257(d)(3)(iii)(B) to show the exit gas temperature is less than the boili ng or bubble point is related to a process vessel with liquid at the boiling or bubble point.

The commenter noted that the material balance requirement in §98.123(b)(1)(i)(B)( 4 )( iii ) may stem from §63.1257(d)(3)(iii)(B), Initial compliance demonstrat ion for condensers, but the material balance requirement is actually from 40 CFR 63.2460(b)(4)(iii), Miscellaneous Organic NESHAP requirements and unrelated to §63.1257( d)(3)(iii)(B). At promulgation of the Miscellaneous Organic NESHAP (following petiti ons for judicial review), EPA responded to public comments by incorporating a requireme nt to conduct a material balance on each component across the condenser. See preambl e discussion at 71 FR 40323; July 14, 2006. To estimate the process emissions co rrectly, facilities must base th e calculation on the condenser receiver component composition and the condenser exit gas temperature condition; the condensate receiver composition for the process condensers is often not available. In the final subpart L rule, the material balance requirement has been revised to note that the material balance on each component is no t required if the condensate rece iver composition for the process

condenser is known.

In summary, to develop the emission calculati on factor, the facility estimates the actual emissions following all process condensers to de termine the uncontrolled emissions. If a process

has a control condenser under the MON definiti on, the facility may calculate the emissions following the control condenser to determine th e controlled emissions. Emission calculations included in §98.123(c)(1)(i) in the fina l rule point to the appropriate calculations to allow this.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 22

Comment: EPA should correct the §98.123(b)(1)(i)(B) citation “except as specified in paragraphs (b)(1)(i)(B)( 1 ) through (b)(1)(i)(B)( 7 ) of this section,” where the section only

includes four subsections.

Response: EPA agrees with the correction comment and has corrected the references for

41§98.123(c)(1)(i)(B)( 1 ) through ( 4 ) in the final rule.



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-106.1 Comment Excerpt Number : 5

Comment: Reduce the complexity of the emission calculation methods.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 1.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 17

Comment: The option to use engineering calculations for the preliminary estimate of emissions by process vent in §98.123(b), and the scoping study is critical and should be further clarified. EPA: The preamble on page 18674 states: “For purposes of estimating the mass of fluorinated GHG emitted from the process, facilities could us e the same types of engineering calculations that they would use to determine whether pr ocess vent testing wa s required under the PSEF approach.” Comment: The propos ed definition of trace compounds in subpart A of the rule is less than 0.1%. Being able to detect each GHG in our vent st reams down to 0.1% will take significant development work to select the prope r analytical method, equipment and standards to do the measurement. This program will take many months and will entail significant cost. Section 98.123(b) requires facilities to do a preliminary estimate of process vent emissions to determine emission factor development me thodology, and section 98.124(a) requires a scoping study. DuPont supports EPA’s decisi on to allow a variety of emi ssion determination methods for these studies, but believes it can be further cl arified. At one of our sites we believe our permitting application calculation basis will meet the requirements for preliminary estimate of

emissions to determine which vents would be >1 Mt/yr before control. These calculations were also acceptable to use for the Miscellaneous Or ganic NESHAP MACT process vent calculations, and makes good sense they are suitable for FGHG emission calculations as well. This site has approximately 170 emission points that potentiall y contain FGHGs at some concentration so documenting new calculation methodologies would be a significant burde n, and unjustified when Title V and HAP regulations have deemed these existing calculations are suitable. There are Pharmaceutical MACT calculations (40 CFR 63.1257...) referenced in the Miscellaneous Organics NESHAPs as acceptable calculati on methods (see §98.123(b)(1)(i)(B)). Under the

Pharmaceutical MACT the use of calculations to comply with other enforceable rules are deemed as acceptable calculation alternatives: “M odified versions of the engineering evaluation methods in paragraphs (d)(2)(i)(A) through (H ) may be used if the owner or operator demonstrates that they have been used to m eet other regulatory oblig ations, and they do not affect applicability assessments or compliance determinations under this subpart GGG. [40 CFR

4263.1257(d)(2)(ii)]”. EPA should incorporate a si milar provision to further clarify suitable engineering calculations alternatives.

Response: EPA has clarified in the final rule that the preliminary emission estimates may be used for both process vents and for identifying proce sses to be included in the initial scoping test. With respect to use of previously conducted engineering calculations or measurements to estimate emissions, we agree that existing data an d existing calculations (i.e., conducted prior to the subpart L effective date) that meet the cal culation methods in subpart L may be used to satisfy the rule requirements, both for preliminary calculations and for calculations needed for developing the emission calculation f actor. It has also been clar ified in the final rule that

calculations conducted to determine emissions unde r other regulatory programs may be used for the preliminary emissions estimate. However, to develop emission calculation factors for process vents, the final rule re quires that facilities conduct a calculation for the emissions for the process vent to develop the emission calculation fact or under subpart L. We have continued with this requirement in the final rule as emissions are often estimated as worse-case estimates or as maximum allowable emissions under other progra ms. Under subpart L emission estimates for emission calculation factor development, the em issions should be representative of typical operation, rather than worst-case.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 10

Comment: EPA has proposed a two-step process ve nt GHG emissions evaluation process. In the first step, the engineering assessment, EPA allows facilities to screen individual vents using a 10,000-mtpy CO 2 e basis to determine further testing requirements. Arkema appreciates the flexibility inherent in the sc reening approach inherent in proposed §98.123(b), where reporters may use engineering calculations to charac terize process vents emitting below 10,000 metric tons per year (“mtpy”) car bon dioxide equivalent (“CO 2 e”). Arkema also appreciates the possibility, outlined at 75 Fed. Reg. 18678/3, wh ere EPA would review existing measurement data for possible use in the proposed §§98.123 and 98.124 FGHG emission determination process. Existing valid data that meets EPA da ta collection procedures should be used when

available.

Response: EPA appreciates the commenter’s support for including a process-vent threshold for the process-vent-specific emissi on factor and emission calculation factor approach. We agree that existing data and existing ca lculations that meet the calculation methods in subpart L may be used to satisfy the rule requirements.

For more discussion of this issue, please s ee the response to comment number EPA-HQ-OAR2009-0927-0103.1, excerpt 17.

43Section 4.3.2 - Cut-offs for Low-Emis sion or Controlled Process Vents



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 25

Comment: In §98.123 (b)(2)(i), EPA has proposed a mass emission and control threshold. For those processes which will not be using the ma terial balance methods that are listed in §98.123 (a), this paragraph delineates whether the Pre liminary estimate of emissions by process vent summarized in §98.123(b)(1) are ade quate or whether the more one rous Process-vent-specific emission factor method summarized in §98.123(b )(3) will be required. 3M agrees that the methods used to measure and report emissions should be commensurate with the emissions quantity. In addition, while we are providing comment on the feasibility, costs, and accuracy of the methods that are required for batch process ve nts (as currently required in the rule), we also recognize that additional field veri fication will be needed to verify and confirm the results of the engineering estimates that are r outinely conducted for batch proce sses in the past for our most significant sources. There are seve ral changes to the thresholds th at are listed in §98.123(b)(ii) which would afford greater flexibility in the use of the engineering estima tes that are listed in §98.123(b)(1) without substantively compromising the integrity of the emission factor

Response: EPA appreciates the commenter’s support for including a process-vent threshold for the process-vent-specific emi ssion factor and emission calcu lation factor approach.



### Commenter: Jeff C. Muffat 

### Organization: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 9

Comment: Destruction Efficiency. We are requesting that the 99.9% destruction efficiency that is listed in §98.123(b)(2)( i)(B) be adjusted to whatever the established performance efficiency of the process is determined to be. 3M has conduc ted destruction efficiency testing on a thermal

oxidizer that is used to treat fluorinat ed-GHG emissions. With the exception of perfluoromethane (CF 4 ), none of these chemicals has ever been measured above the method

detection limit at the outlet of this unit. The chem ical-specific destruction efficiencies have been

based on the method detection limits for each chemical . For past reports, we have utilized these measured chemical-specific destruction efficien cies in determining outlet emissions from the oxidizer. Since the values of some of the input constituents can be quite low, the destruction

efficiencies have also been low. Where the conc entration of the inlet va lue is high and/or where the outlet detection limit is low, the destruc tion efficiencies are also high. For example SF 6 , which has a very low detection limit, has a calculated DE of nearly 100%. With the promulgation of these rules, 3M will likely adopt a modified approach. EPA provides for the use of an appropriate chemical “surrogate” and it is possible that a 100% DE has already been

established for most of the materials that are present, i.e., value obtained for SF 6 demonstrates 100% DE. In the case of perfluoromethane, 3M believes that the DE values established during

44the past testing (and any future tests) should be adequate and a DE value of any amount should

be sufficient if it is based on the test cond itions that are establ ished in the rules.

Response: A response has been provided in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Production (Subpart L)).



### Commenter: Jeff C. Muffat 

### Organization: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 11

Comment: In addition to a modified determinati on threshold, 3M also requests that the

determination thresholds listed in §98.123 (b)(2)(i) (A) and (B) be the sum of the controlled and uncontrolled emissions. Voluntary control devices may be used in certain applications and/or situations may exist where bypasses occur ar ound thermal treatment devices. During these situations, the facility would simply report the sum of the controlled and uncontrolled emissions using methods that are described in §98.123 (b)(1) w ith the destruction effi ciency being used to determine the chemical specific destruction effi ciency at the outlet of the thermal treatment device. 3M currently uses this method today. If and when the determination threshold was exceeded, the facility would presumably be required to conduct emissions estimates using an

alternative method and within a reasonable time frame.

Response: A response has been provided in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Production (Subpart L)).



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 22

Comment: We are recommending certain changes to the thresholds that have established for the “preliminary estimates” and vent testing requireme nts. This includes the threshold itself as well as the destruction efficiency requirement.

Response: A response has been provided in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Production (Subpart L)).



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 14

45Comment: EPA appropriately does not require source testing of vents emitting, on an uncontrolled basis, less than 10,000-mtpy CO 2 e at proposed §98.123(b)(2)(i)(A). However, EPA should further clarify that, below a certain thre shold that reporters need only document that a specific vent does not have a potential to reach a specific fraction of this 10,000-mtpy CO 2 e level. In the Title V program, permitting author ities typically reduce calculation scrutiny for vents emitting less than 5% of the major source th resholds for all regulated pollutants. Applying this logic to Subpart L, we r ecommend that EPA only require listing of process vents with an uncontrolled potential to emit of less than 5% of the 10,000-mtpy CO 2 e threshold, or less than 500-mtpy CO 2 e per vent.

Response: No de minimis level of emissions or minimum evaluation threshold has been

included in the final rule. Because this is a re porting rule, we consider it appropriate to require reporting of emissions from all processes and em ission points included in subpart L. However, the rule recognizes that the effo rt required to estimate emissi ons should be reflective of the magnitude of the emissions, and for continuous vents, a process vent threshold of 10,000

mtCO 2 e has been included, with differing levels of ef fort for those above and below this level. For continuous process vents above this level, fa cilities are required to conduct emissions testing to develop the emissions factor; for continuous process vents belo w this level, facilities are required to conduct calculations to deve lop the emission calculation factor.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 15

Comment: Not all FGHGs may be listed in Tabl e A-1. For consistency, we recommend that

EPA use a similar 5% minimum evaluation thre shold for non-Table A-1 compounds to provide a

minimum review threshold. This mass rate th reshold for non Table A-1 compounds would be 0.05 tpy (100 pounds per year (“lb /yr”)). This proposal would a llow reporters to minimize the effort required to document very small vents that do not significan tly contribute to FGHG

emissions.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 14.



### Commenter: Jeff C. Muffat 

### Organization: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 10

Comment: Mass Reporting Thresholds. Fluorinated-GHG’s that are not listed in Table A-1 are present in most of 3M’s process air exha usts and as a practical matter the 10,000 mT CO 2 e listed in this paragraph will not be used for complian ce determinations. By default 3M will be using the 1 mT /year threshold. In EPA’s requests for comments they have considered other thresholds

46and a 10,000 pound mass fluorinated-GHG threshold was provided as an example. This value provided by EPA is better aligned with the permitti ng thresholds that have been listed in the Prevention of Significant Deterioration and Title V Greenhouse Gas Tailoring Rule. In that rule EPA has indicated that even in the latter stages of this program, permitting would not be required for sources below 50,000 mT CO 2 e /yr. 3M requests that the determination value be increased to the 10,000 lb mass F-GHG/year level. The exampl e provided in Attachme nt 1 illustrates the value of the increased threshold. In this case, emissions of non-Table A-1, low GWP materials would not be required for a num ber of operating scenarios.

Response: As discussed in the preamble of the fina l rule, EPA has made several changes to the manner in which facilities are required to ma ke preliminary estimates of emissions for comparison with the 10,000 mtCO 2 e cut-off. One of these is to re quire facilities to use a default GWP of 2,000 to estimate the CO 2 e of fluorinated GHGs that do not have a GWP listed in Table A-1. (Facilities may also request to use a provi sional GWP; the circumstances under which they may make this request are discussed in the preamble.) At a GWP of 2,000, the 10,000-lb mass threshold suggested by the commenter equates to 9,091 mtCO 2 e, which is very close to the 10,000 mtCO 2 e threshold in the final rule. Please s ee the response to comments regarding GWPs and the process vent threshold that has been pr ovided in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Production (Subpart L)).



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 16

Comment: If EPA is not able to incorporate a provision to calculate GWP for chemicals not listed on Table A-1, the agency should adopt a 10 mtn/yr mass exclusion level for determining the appropriate emission factor methodology in secti on 98.123(b)(2)(A).

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 10.



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 17

Comment: The process-specific emissions factor appr oach avoids some of these problems [with the mass-balance approach], and EPA should maintain it for most sources. We urge EPA to reject suggestions that would weaken that appr oach. In particular, EP A should limit the use of engineering calculations, instead favoring direct monitoring of process vents, and should not

raise the emissions threshold below wh ich such calculations can be used.

47Response: As discussed in the preamble of the final rule, EPA is permitting the use of engineering calculations to estima te emissions from batch process vents, regardless of size, due

to technical issues that make it difficult to de velop accurate emission factors for batch process vents based on emission testing. For continuous process vents, EPA has retained the 10,000

mtCO 2 e cut-off for emission testing, although we have changed the manner in which facilities are required to make preliminary estimates of emissions for comparison with the 10,000 mtCO 2 e cut-off. These changes make reasonable accomm odations for the use of control devices and for

emissions of fluorinated GHGs that do not have GWPs listed in Table A-1. With these changes, EPA believes that the rigor of em ission estimation method is appropr iately linked to the size and

technical characteristics of the emissions source.



### Commenter: Craig Holt Segall 

### Organization: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 12

Comment: We also support EPA’s decision to use uncontrolled emissions to determine the rule’s applicability, rather than controlled emissions. Control devices may malfunction and facilities may develop leaks or emit by-products th at control devices cannot address. Facilities should not, therefore, be able to rely upon control devices to evade reporting.

Response: EPA appreciates the comment.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 16

Comment: For those streams that are fed to a destruction device, measuring GHG emissions post-destruction device provides an incentive for facilities to reduce GHG emissions as well as alleviate much of the burden of this subpart.

Response: Under the revised approach for conducti ng emissions testing for emission factor development, facilities may estimate a controlled emission factor by testi ng at the outlet of the destruction device, as long as th e total “uncontrolled” emissions , i.e., during periods when the process vent is not vented to the de struction device, are less than 10,000 mtCO 2 e. In addition to the controlled emission factor, if a process e xperiences any periods when not vented to the destruction device, the facility must also develop an emission cal culation factor for these periods when the process vent is not vented to the destru ction device. The final ru le also allows testing for emission factor development following a wet sc rubber that is in plac e for acid gas removal, either HF or HCl, as long as there is no appr eciable reductio n of the fluorinated GHG. For process vent streams where the total “uncont rolled” emissions are greater than 10,000 mtCO 2 e, facilities must conduct emission testi ng on the uncontrolled emissions.

48

### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 17

Comment: In addition, it [i.e., measurements post-de struction device] removes any safety risk to employees and contractors from having to samp le hazardous materials in high concentrations (such as HF) that may be present in upstream processes.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 16.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 19

Comment: Facilities constantly mon itor the operation of destructi on devices, and would be able to quickly react to any failure in the destruction device. (For ex ample, caustic wet gas scrubbers are continuously monitored for th e injection flow rate, differen tial pressure across the packed sections, and pH.) Allowing for the use of e ngineering calculations for periods when the destruction device(s) are o ffline would ensure accura te GHG emissions accounting.

In addition, EPA should explicitly cross-refere nce existing compliance ob ligations under 40 CFR 51, 52, 60, 61, 63, 64, 65, 70, 71, and 75 as appropriate compliance methods for process units impacted by one or more of these requirements.

Response: Regarding the estimation of emission dur ing periods when destruction devices are on- or off-line, please see the respon se to comment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 16. The current compliance mon itoring obligations (e.g., compliance assurance monitoring under 40 CFR 64, or compliance m onitoring under 40 CFR 63) from other regulatory programs applicable to control devices in place for fluorinated GHGs are not specifically cross-referenced in the final rule. However, the ru le does require that facilities report emissions that may occur from malfunctions of control devices or processes or that occur during periods when the control device is opera ting outside of operating conditions set for the device in the facility’s operating permit. .



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 18

49Comment: EPA should also keep in mind that the re lationship between process stream contents and process vent emission rates varies between processes and within processes. A vent stream seemingly potentially causing substantial poten tial emissions, may, for process reasons, not contribute to potential FGHG emi ssions. Another process stream with seemingly trivial amounts of FGHG may, for process reason s, become a significant FGHG emissions contributor. Because the relationship between stream content and FGHG emissions are necessarily case-by-case determinations, EPA should carefully weigh any inferences before concluding any relationship between stream composition and FGHG emission rates.

Response: EPA agrees that stream composition is not necessarily related to fluorinated GHG emission rates, e.g., in cases where the stream or some components of the stream are recaptured or destroyed. The initial scoping test is inte nded to identify the set of fluorinated GHGs that occur in the process and therefore may be em itted by it, not necessarily the fluorinated GHGs that are emitted from the process. Nevertheless, EPA expects that faciliti es will include in their emissions measurements (emission testing or emi ssion characterizations) fluorinated GHGs that have been identified in the initial scoping test and that could occur in the tested stream.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 19

Comment: EPA should clarify that this limit is pe r vent in batch appl ications, and not for individual batch steps vented through the same emission point. EPA should also explain how the 99.9% destruction and removal efficiency (“DR E”) criteria at proposed §98.123(b)(2)(i)(B). We

believe that the 99.9% was derive d from EPA’s control device effi ciency research conducted to support this proposal. However, EPA should allow pos t-control efficiencies for vents that may be controlled by DRE less than 99.9%. We believe th at, were we to find FGHG vents controlled by less than 99.9% DRE, the proposed regulati on requires us to switc h to the uncontrolled calculation basis. Similar requirements in other EP A authorities, such as the Hazardous Organic NESHAP (“HON”) at 40 CFR 63 Subpart G, recognize control efficiencies of 95% or greater. This strict cutoff may cause unnecessary charac terization of controlled FGHG vents and serves as a disincentive for reporters to control s upplemental vents when less than 99.9% DRE is

available.

Response: As discussed in the preamble, we are allowing facilities to use emission calculation factors for all batch processes regardless of size due to several technical issues that make it difficult to develop accurate emission factors fo r batch process vents base d on emission testing.

Please see the preamble to the final rule for a di scussion of how the final rule requires facilities to treat destruction efficiencies in their preliminar y estimates of emissions from the process vent.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.

50

### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 16

Comment: EPA should adopt a low-concentration fl oor below which reporters do not need to document FGHG content of process streams. Several process streams in fluorochemical manufacturing process units may contain a triv ial amount of FGHG, cau sing trivial amounts of FGHG emissions. At §98.416(c) and (d) of S ubpart OO, EPA defines a floor below which FGHG reporting is not required. EPA should adop t a similar guideline, based on Subpart OO conditions in effect when Subpa rt L reporting begins, allowing re porters to not document process streams containing less than the Subpart OO mass concentration threshold in effect when Subpart L reporting begins. Arkema expects to id entify several process streams, including coproduct hydrochloric acid, containing minimal F GHG concentrations that will not significantly impact actual FGHG process emissions. This minimum FGHG concentration threshold will allow reporters to concentrate on documenting F GHG contents of streams that could potentially impact actual FGHG emissions.

Response: Please see section 10 of this RTC documen t for discussion of trace concentrations, including the definition of “trace concentration” and how trace concentrations are treated in the monitoring provisions of the final rule.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 43

Comment: Third, EPA should clarify that the 99.9% DRE requirement for control devices not regulated by the HWC MACT is not a permit limit, and that reporters only need to recalculate FGHG DRE. EPA should clarify that this pro cess change provision does not constitute an emission control requirement and does not requir e reporters to replace emission control devices during a process change.

Response: The process vent threshold criterion for DE has been eliminated from the final rule. While no longer in the rule, we would like to clarif y that at re-proposal it was not meant to be an emission control requirement.

Please see section II.E.3 of the preamble to this rule for more discussion of this issue.

Section 4.3.4 - Emission Factor Approach

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 28

51Comment: Batch Processes Vents. Where as we commonly characterized our continuous process vents using the methods that are proposed in the rule, these same procedures have not been utilized on many batch process vents. 3M u nderstands EPA’s desire fo r field verification in the form of specific vent gas emission testing and we are prepared to undertake this effort for the most significant emission sources. However, ba tch processes present unique vent testing challenges. This has been recognized in a numbe r of previous EPA-rulemaking activities. There is no single approach which can be used for emissions characterization and in some cases a combination of methods must be employed to obta in the appropriate emission factor. We believe that EPA should simply allow for the use of the methods that are described in §98.123 (b)(1) with the additional requirement that more generally states that “Batch emissions in excess of the

determination threshold must include some fi eld verification, in the form of stack gas measurements that characterize the major emission events.”

The specific concerns with batch testing requirements are summariz ed in greater detail below:

1. Many batch processes have extended cycle times, i.e. 24-48 hours. The time required to complete three test cycles could take weeks. With a continuous process, some determination of

RSD conformance could be made at the time of th e test. This would not be the case with batch processes where data would be collated well af ter the test is completed. We believe that compliance with an RSD for each constituent would require six (6) tests for all batch processes requiring additional field tests. Where products ar e made on a campaign basis, this could require in excess of one year for comple tion. There are also may be cases where six (6) tests could not be completed and the rules should provide for so me relief when sufficient tests cannot be

conducted.

2. In previous regulatory initiatives, EPA has recognized the uniqueness of batch processes. At the request of 3M, Dixon Environmental has summ arized these various references and findings in Attachment 2. The major themes that are captured in the document are listed below: a. Engineering calculations th at are based on chemical engin eering principals have been recognized as the “state-of-the art” for batch processes and in many cases they are the required

method. b. The methods described in (a) cannot always be utilized. In these cases, previous rulemaking efforts have acknowledged that a multitude of approaches listed unde r §98.123(b)(1) could be utilized. The default requirement has never been vent testing.

3. We have certain processes where batch emissions can be measured using the methods that are

listed in the rule. In some cases , processes will be discharged through induced draft fans that operate at a constant flow rate. Measurement in these processes is not dissimilar to continuous operations since only chemical concentration will vary. However, more commonly these vents will consist of small diameter process piping wher e the use of traditional gas flow measurement

devices are not effective or wh ere piping and equipment modificat ions are not feasible and/or safe. We are concerned that the integration of varying concentration with varying flows will severely limit the useful ness of this information for all emission episodes. Operations that may be particularly difficu lt to measure include: a. Depressurizations where gas flows are not continuous and/or which will begin and conclude quickly.

52b. Vapor displacement, which may occur during r eactor filling, resulting in extremely low and

non-measurable air flows. c. In some cases, a number of samples may be ob tained to monitor the reaction process and each could involve a minor depressurization. These steps are normally not significant emission contributors but each constitutes a separate “episode” which would require measurement.

4. 3M currently uses a combination of lab, pilo t plant, and factory data to develop emission factors for some its major batch processes. Data from process development at the laboratory and pilot plant scale is combined with factory data to establish an estimated material balance model for the processes, providing a fairly accurate picture of ai r and water emissions, waste to incineration, and estimated product output. A deta iled analysis of these major streams is also necessary to understand levels of potential by-products and overall product quality. Many techniques are employed for stream analyses including F-NMR, H-NMR, GS-MS, LC, IC, and ICP. During scale-up at the factory level, critic al streams are sampled and compared against the original model which is adjusted accordingly.

These analyses are used to 1) establish the ex tent of reactions for th e primary (formation of product) and secondary reactions (byproducts, side-reactions), and 2) determine how the components (primary product, by-products, co mponents from side reactions, and inert compounds), partition between the process streams. The extent of reaction and partitioning data for the major components is then applied to minor components using engineering judgment (physical property information, water solubility, etc.) whose levels are either below detection limit or where there is more uncertainty in the analytical data (e.g., the component may be above

detection limit in one stream but below th e detection limit in another stream).

The resulting compositions predicted by the materi al balance model is cross checked against the individual stream analyses of critical compone nts, raw material charges, and stream flow

measurements to achieve an overall fit to the da ta available. The material balance model is

constructed so that the balance must close for ev ery species for each step of the operation as well as the operation overall. While ther e are estimates and assumptions made using this approach, all compounds are accounted for in th e model with an objective to ach ieve good agreement with all analytical data and measured factory input a nd output quantities. Ma terial balances are constantly refined when required. It must be noted that there is no statistical analysis performed to determine the “best fit”, because of the extreme complexity of the material balance (the typical balance includes approximately 100 components) and the very high cost and time associated with the techniques required to analyze these streams.

In summary, there is no single approach that can be used to characterize batch emissions. These operations are diverse. Specific emission episod es may be both significant and insignificant. Physical property information may or may not be available. Pollution control may be in place to substantively mitigate or eliminate emissions. Detailed laboratory evaluations, conducted under carefully controlled conditions and utilizing more powerful laboratory techniques will yield emission factors of high quality which can be confirmed by monitoring a key process variables(s). Facilities that are reporting under this source ca tegory and for these types of operations need to be afforded the flexibility in selecting the most appr opriate method, especially in light of EPA’s desire to obtain the most accurate information.

53Response: Please see the preamble of the final ru le for a response to this comment.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 29

Comment: Section 98.124 (c)(4 )(i-iv) specifies gas flow measurement methods. Some batch process emissions will consist of gas streams th at do not contain a significant amount of air. In addition, process emission vent piping systems ar e closed systems that ar e not easily adapted to these types of measurements. Inlet measurements to thermal oxidizers are typically measured with the types of mass flow me ters that are commonly used in Subpart OO. The rule should

allow flow rate data from these mass flow mete rs or other on-line flow measurement equipment.

Response: Please see the preamble of the final ru le for a response to this comment.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 12

Comment: §98.123 (b)(3), Process-Vent-specific em ission factor method. Many of these processes will involve batch em ission episodes where the con centration and flow-rate may change over time. Therefore the values of C PV-ee and QP V-ee in equation L-14 are not constant. If not already EPA’s intention, we would request that average C PV-ee and Q PV-ee values be used in the calculation. For example the values of C PV-ee and Q PV-ee could be measured at least three times during the batch and the average va lues used. If available, continuous measurements using FTIR

and on-line mass flow meters c ould also be used to calculate the total mass of a GHG emitted during the batch. This method will not be possi ble for all batch proce sses and depends on the complexity of chemical composition of the pr ocess, the operating pressure and manufacturing equipment that is used.

Response: Please see the preamble of the final ru le for a response to this comment.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 14

Comment: §98.124 (c) Emission Factor Te sting. In this section, EPA specifies the frequency and type of emissions testing th at is required to create emissions factors. Specific comments for each paragraph in that section are provided below. 3M has conducted vent gas measurements on

54most of its continuous process ve nts. While this type of tes ting has not been conducted on most batch processes, we recognize EPA’ s desire to confirm engineeri ng estimates with field testing for the highest emitting processes. We are prepar ed to conduct this wor k, but the regulation is overly specific with respect to the test accur acy and measurement fre quency. We also believe that it is incorrect to rely exclusively on proces s vent testing in the development of the emission factors. Batch process vent measurements must be properly coupled wi th other techniques to cost-effectively produce the most accurate and reliable emission f actors. In addition, we believe that engineering calculations and sound materi als balances conducted und er carefully controlled circumstances will result in the development of emission factors of equal or greater accuracy.

Response: Please see the preamble of the final ru le for a response to this comment.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 16

Comment: 3M has particular concerns with the ba tch process testing requirements and we are requesting that EPA refer to the language that is listed in §98.123 (b)(1 ) for all batch process

vents. Our concerns are discusse d in our response to §98.124(c)(3).

Response: Please see the preamble of the final rule for a response to this comment.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 26

Comment: Batch stack testing per §98.124(a) is typically impreci se, and costly. Engineering

calculations should be allowed regardless of vent emission rate. EPA: Page 18677 of the preamble states “ and for batch process vents, fa cilities would test duri ng emissions episodes of the batch....another option is to re quire testing of vents for the fu ll duration of the batch process, but this could significantly increase the expens e of the emissions test without necessarily improving its accuracy.” Comment: The concern about testing of batch processes is not when to do the test (i.e. do it when the process vent is op en) or the test protocol (stack test protocol options are well established) but ho w to get a representative sample and representative flow rate. To get a representative emission rate using stac k sampling, the vent rate and composition need to be relatively constant and/or predictable ove r the sampling period. This cannot be accomplished with many of our batch operations. At least two of our sites have batch unit operation vents that

are closed for almost the entire batch. At se lected moments during the batch, unneeded pressure is vented from the unit operation (i.e. the vapor space is vented down from some higher pressure to some lower pressure). The flow rate of vapor through the vent stack changes and the composition of the vented vapor changes as the pressure in the unit operation vapor space decreases over the period of venting. Depending on the process equipment, the vent step can

55occur within as little time as a few seconds or at most up to a few minutes . The issues that this creates for stack sampling are:

1. The vent period is too short to collect a meaningful sample or to collect the velocity profile data required by stack testing protocol. 2. The vent composition varies dram atically over the vent period.

3. The vent rate varies drama tically over the vent period.

For these reasons, we cannot obtain meaningful stack test emission data. There are EPA approved methods for calculating these emission s. We are already using these methods to calculate our air emissions for Title V. We propose that if these emissions need to be determined, using the calculation methods shoul d be the approved approach to estimate the emissions. The recent Miscellaneous Organic NESHAP MACT recognizes these issues and only requires engineering calculations.

Response: Please see the preamble of the final ru le for a response to this comment.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 3

Comment: 5. Source testing can be an extremely problematic for batch processes. A diverse toolbox of methods, traditionally referred to as “e ngineering estimates”, is needed in order to obtain the best possible information.

Response: Please see the preamble of the final ru le for a response to this comment.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 24

Comment: §98.123 (b)(1), Preliminary estimate of em issions by process vent. 3M generally agrees with the calculation met hods that are listed in this se ction. We believe that EPA should also limit the requirements for emission factors fr om batch processes or batch emission episodes of continuous processes to the methods that are li sted in this section. Th e process vent testing

methods that are listed in §98.124 (c)(4) should be listed as additional alternatives.

Response: Please see the preamble of the final ru le for a response to this comment.

56Section 4.3.5 – Scope of the Emission Factor



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 21

Comment: Arkema understands why EPA proposes to require reporters to document FGHG

emissions from control device deviations a nd startup, shutdown, and malfunction (“SSM”) events. EPA should clarify that the §98.123(b)(1) cal culation methods are appr opriate to evaluate

these emissions.

Response: As the commenter suggested, 98.124(j) has been revised to include a statement that calculation methods in §98.123(c)(1) may be used to estimate emissions startup, shutdown, or

malfunction events.

Section 4.3.6 - Equipment Leaks

Section 4.3.6.1 – Alternative monitoring approaches for equipment leaks



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 23

Comment: A variety of methods should be made available for determining equipment leak

emissions. It is our belief that emissions from many of these sources are low and warrant this consideration. We are providing EPA with additi onal technical informa tion to support this

request.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 20b

Comment: Allow EPA approved alternative equipmen t leak emission estimation methods. 3M has utilized a number of methods in estimating equipment leak emissions from its processes.

These include the methods that are describe d EPA-453/R-95-017 (Protocol for Equipment Leak Emission Estimates). 3M also uses system pressure and vacuum checks to meet LDAR requirements for many batch operations. These are described in 40 CFR 63.1036 (Alternative

57means of emission limitations: batch processes, (b) Pressure testing of batch equipment). For these components, we are not currently conducting the traditional Method 21 monitoring that is

referenced in the rules. In some of these situations we have also used this information to estimate fugitive losses from these processes. In these cas es the equipment leak loss from the process is calculated based on the pressure drop and system volume. Since the actual pressure drop will be less than the allowable loss during the pressure/vacuum check, this value will always be

conservative. 3M would not elect to use this method under every circumstance. However it will be appropriate for a number of operations. This could be the case for low-GWP emissions or for flexible batch process equipment that is used to manufacture fluorinated-GHG’s on a very limited basis. In the latter case process vent emi ssions will be very low, but an equipment leak estimate is required irrespective of those emissions or the time in service. For these operations the use of data derived from a system pressure check may be appropriate as emissions will be very low. Finally, as discussed in Attachment 2, there may be situations where an EPA 204 capture efficiency demonstration will be appropri ate for a specific process or group of processes. A single test, conducted at a location which repres ents emissions from an entire process, may greatly simplify measurement requirements.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 21

Comment: In this proposal, EPA is requesting that the fluorochemical industry create a new fluorinated GHG equipment leak de tection program. Unfortunately, due to the variability in the fluorochemistry industry, ther e is no one size fits all fluor inated GHG EL detection solution. Subpart L EL detection systems should provide enough flexibility to allow reporters to craft appropriate fugitive emission reporting system s. EPA should allow reporters to document appropriate EL detection practices for each a ffected facility in the GHG Monitoring Plan required in §98.3(g)(5).

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 17

Comment: 98.124 (e) (3), Emission monitoring for pieces of equipment. The citation references bagging requirements followed by EPA Method 18 analytical pr ocedures. We suggest that canister samples from the bags could be taken and could alternatively follow EPA TO-14a

58and TO-15. Should unknown compounds be present, or compounds for which certifiable standards do not exist, GC/MS can be used to identify them. When standards for the analyze are not available, a chemically similar su rrogate may be used for quantification.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 20e

Comment: 3. EPA has recognized that unique instrumentation may be required to measure many of these constituents. For flexible batch pro cesses, it is possible that testing conducted for the purpose of developing leak rate factors c ould be conducted when fl uorinated-GHG’s were not present in the system. During these periods non-F-GHG surrogates would be used to develop this information. The rule language should insure that this type of de monstration is allowed.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 31

Comment: At proposed §98.123(c), EPA removes the option of using the “Average Emission Factor Approach” (EPA, Protocol for Equi pment Leak Emission Estimates, EPA-453/R-95-017 Table 2-1, 1995), even for components where tr aditional Method 21 monitoring is impossible. EPA should strike this prohibition.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 25

Comment: Many Subpart L reporting facilities currently conduct LDAR to comply with the Hazardous Organic NESHAP (“HON”) at 40 CF R 63 Subparts F, G, H, and I or the Miscellaneous Organic NESHAP (“MON”) at 40 CFR 63 Subpart FFFF (incorporating 40 CFR

5963 Subpart H or UU LDAR provi sions). The EPA MACT LDAR regulations contain several provisions that may be necessary for any pr ospective GHG LDAR program. As reporting facilities have not previously been required to conduct GHG LDAR, the industry will need to determine which FGHGs may be detected by whic h LDAR instruments. As we implement this program, we may learn that some FGHGs may no t be detectable by existing LDAR equipment. The current proposal requires use of EPA Method 21 (40 CFR 60 Appendix A), which includes a gas chromatograph with a flame ionization detector. Method 21 requi res that reporters

demonstrate that the measured stream can be de tected with a response fa ctor of less than 10.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 26

Comment: Proposed §98.126(e) requires reporters to use methane as the Method 21 calibration gas. As methane may or may not be an appropr iate calibration gas, based on the discussion above, EPA should strike the last sentence of this subpart. EPA should rely on the proposed §98.123(c)(1) provision that reporters maintain res ponse factors below 10 to provide appropriate

methods controls for FGHG LDAR emissions meas urements. A forced calibration gas selection may conflict with the more appropriate response factor ra nge requirement.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 30

Comment: Section §98.124(e) requires that EL mon itoring instruments be calibrated using methane gas. However, ACC member companies may need to use instruments that do not meet the criteria of methane calibration gas and a resp onse factor less than 10. EPA should rely on the existing Method 21 response factor criteria, a nd allow reporters to calibrate EL monitoring instruments with any appropria te calibration gas that provides proper response factors for targeted fluorinated GHGs.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.

60

### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 27

Comment: EPA does not provide any re gulatory structure to address either alternate instrument selection nor appropriate monito ring surrogate selection. Today, f acilities requiring an alternate instrument determination for a specific stream re quest authorization from EPA and/or the local permitting authority. As Part 98 is designed to me morialize these technica l decisions in the GHG Monitoring Plan required at §98.3( g)(5), EPA should require reporte rs to document the choice of LDAR instruments in the Monitoring Plan. EPA should also adopt the 5% surrogate threshold, where a facility would, by process knowledge, docum ent the identity of any surrogates in process streams that are monitored, a nd the appropriate Method 21 or alternate applic ation to the identified components.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 24a

Comment: Some fluorochemical manuf acturing units may be amenable to pressure LDAR testing at 40 CFR 63.1036. EPA should allow this LDAR alternate monitoring method in lieu of Method 21. In addition, EPA should not discourage the recent EPA alternate LDAR monitoring program at 40 CFR 63.11(c). While many fluorochemical manufacturer s are not yet able to use this emerging technology, EPA should facilita te reporters adopting “smart LDAR” technology when it becomes available to the industry.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 29

Comment: We are exploring remote fugitive de tection technology, but have not yet found a marketed system that can detect FGHGs. EPA should note in proposed §98.123(c) that a reporter may utilize any LDAR methodology and technology recognized by EPA, including EPA Method 21 remote sensing alternatives in 40 CFR 63.11(c), (d ), and (e). EPA shoul d also allow reporters to utilize any future LDAR t echnology final in or authorized by 40 CFR parts 60, 61, 63 and/or

6165. EPA should require that repor ters identify adjustments to the base FGHG LDAR program in their §98.3(g)(5) GHG monitoring plan.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Thomas J. Scanlon


### Commenter Affiliation: FLIR Systems, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-105.1 Comment Excerpt Number : 3

Comment: Thus, FLIR Systems en dorses the EPA suggestion 10 that optical gas imaging (OGI) and the alternative work practi ce (AWP) Method 21 be utilized to monitor leaks in Fluorinated Gas Production systems and specifically in SF 6 production. However, we see no reason why OGI

for detection of leaks in SF 6 production systems should be less of a requirement than it is for methane and natural gas. This gas has a globa l warming potential over 22,000 times higher than

CO 2 and over 1000 times greater th an methane an d natural gas 11 . FLIR Systems respectfully requests that EPA consider modifying certain provisions of the proposed Subpart I, L, DD, QQ,

and SS rule to ensure that the full potential of this technology is exploited. We recommend that

EPA:

• Require the use of OGI technology fo r monitoring gas leaks on all SF 6 gas production systems in the same way it will be require d for natural gas production and transportation.

Optical Gas Imaging has been proven as a reliabl e in-field technology for detection of a wide variety of volatile organic compounds and SF 6 . Detection of Fluorinated gases and HFCs, PFCs in particular uses the same basic technology approach and the same detector technology we deploy for the camera used to detect SF 6 , but the market demand for these camera products has been minimal since there is no regulatory demand to detect these gases and leaks for these gases do not have the same safety and economic conseque nces inherent in large losses of methane or natural gas.

For this reason, we recommend that EPA:

• Move forward with the sugges tion that AWP Method 21 protocol be utilized to monitor leaks in Fluorinated Gas Production systems.

Since the Method 21 protocol allo ws for either probe technol ogy or optical imaging, producers will be encouraged but not required to use OGI.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.

10 Federal Register / Vol. 75, No. 69 / Monday, April 12, 2010 / Proposed Rules 18679.

11 GWP values and lifetimes from 2007 IPCC AR4 p. 212.

62Section 4.3.6.2 - Contribution of leaks to facility emissions



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 20a

Comment: §98.123 (c), Calculate fluor inated GHG emissions for equipment leaks (EL). In conjunction with the process specific emission factors, 3M understands that it will be necessary to estimate leaks from equipment. As a part of preparing these comments, 3M conducted a sampling survey for one of its fluorinated- GHG production operations. A summary report is provided in Attachment 3. Various references are made to that document in the comments listed

below. Due to time limitation we were not able to prepare a more comprehensive report. 3M will submit this information at EPA’s request.

1. Emissions from equipment leaks will be very low. Leak Detection and Repair Programs (LDAR) are in place for most of 3M’s chemical manufacturing operations. Leak rates, i.e. fraction of equipment where measurable concen trations have been detected, are typically extremely low. As reported in Attachment 1, one of our fluorinated-GHG manufacturing

facilities conducts testin g using 40 CFR Part 63 Subpart H. This particular process utilizes chemistry which has an acceptable Method 21 res ponse factor (vinylidine fluoride). Over 4000 devices are monitored as a part of this testing. The annual averag e leak rate was less than 0.1%.

A review was conducted of the data and for most of this equipment the measured values were equal to background concentrations. When appl ying the methods that are listed in EPA-453/R95-017 (Protocol for Equipment Leak Emission Estim ates) the “default zero leak rate factor”

would be used for most of this informati on with the balance usi ng the “screening value correlation”. We believe that the resulting mass emission rates for the facility would be low.

At another facility, Method 21 testing has been c onducted under Subpart UU for a facility that is subject to 40 CFR Part 63, Subpart JJJ. Testi ng is conducted at variab le frequencies for over 1000 different pieces of equipment. During the last four years, there has been only one device (and on only one occasion) that exceeded the regula tory threshold. At one of its facilities, 3M conducted Method 21 screening to determine the im pact of MACT requirements which regulate emissions of Hazardous Air Pollutants (HAP). 3M conducted screening on over 5000 flanges, valves, and other affected equipment. Of thes e, approximately 0.3% were determined to be “leaking” based on the 40 CFR 63 Subpart UU standa rds. The data that wa s collected at this facility was subsequently used to prepare estim ates for air emission inventory reports and to comply to specific permit requirements for Hazar dous Air Pollutants. For approximately 40% of the fittings, the “default zero le ak rate” was utilized (no value detected above background). For the balance, a "screening value correlation" factor for measured concentrations of less than 1 ppmv above background, but less than the leak designation, e.g., 500 ppm for valves, was used. Emission rates for equipment were calculated with these factors and the sum of these values was

less than 1% of the tota l site HAP emissions. In conclusion, while we agree that estimates may be a necessary part of the emi ssion factor approach, EPA should be extremely flexible in the

63manner in which these estimates are made and the verification frequency for individual pieces of equipment.

2. Institutional controls are in place to prevent, detect, and remediate leaking equipment. The results of previous LDAR monitoring programs ar e not unexpected due to various controls that are in place at all of our chem ical manufacturing facilities, in cluding those that are used to manufacture and process fluorinated-GHG’s. Equi pment leakage rates at 3M facilities have typically been well below values described in the technical guidance documents that EPA has prepared as a part of various rulemaking efforts, e.g. NESHAP standards. 3M believes that other industries in this source categor y would have similar results. We believe the low leakage rates

are the result of a number of factors:

a. OSHA mechanical integrity pr ogram which is intended to pr ovide for the proper design and testing of all process vessels, piping, relief devices, emerge ncy shutdown system, and control systems. This will include a schedule for the inspection and testing of system components.

b. Pressure and vacuum checks are conducted rout inely at the start of manufacturing campaigns or when system components are replaced. Leaks that are detected during these checks will be repaired prior to start-up. c. Ambient air quality monitoring for hydrofluoric acid is conducted in many of our fluorinatedGHG production processes. Leaks that occur fromequipment components will be repaired when

detected. d. Value of product loss to fugitives.

These procedures, in addition to normal routine inspections of manufacturing areas, will ensure

that the low measured leak rates are maintaine d. Testing frequencies should be extended for facilities that incorporate these practices.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 20c

Comment: In light of the very low emissions that are expected from these sources and the institutional controls that are in place to maintain this level of performance, 3M would have the following recommendations:

1. The rule should provide for a wide range of estim ation methods that can be customized to site operations. For example, the use of FTIR instru mentation is effective but an expensive and resource intensive approach, especially if te sting was required at th e one year frequency specified in the rule. However, th e method could be used to “surve y” a representative sample of equipment at a facility and leak factors could be applied facility-wide. These surveys could be

64married with system pressure checks and th e results of a Method 204 capture efficiency

demonstration could also be applied facility wide.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 20

Comment: Equipment leak monitoring is expensive, emissions are de minimis and should not be required for emission estimating purposes. EP A: Section 98.123(c) states: “If you comply with paragraph (b) of this section, you must calculate the fluorin ated GHG emissions from pieces of equipment associated with processes covered under this su bpart and in fluorinated GHG

service.” Comment: The costs associated with equipment leak monitoring are not justified based on DuPont’s experience using Method 21 fo r VOC leaks at our chemical plants. In addition, Method 21 is inappropriate for some non-VOC fluorochemical s. (see Appendix B) For example, at one of our sites (that is typical of our company experience) the total VOC emissions for 10 production units for 2008 & 2009 was 1154 lbs. This resulted from LDAR inspections for approximately 2000 valves, 6000 connectors and 50 pumps. The overall leak rate in 2008 was connectors, 0.029%; valves, 0.45%; pu mps 0% (no leakers). The emi ssions are insignificant and de minimis compared to total production. If EPA insists on an equipment leak program, then it should be infrequent, i.e. up to 5 year intervals, based on leak frequency.

Response: A response has been provided in secti on II.E.3, Fluorinated Gas Production (Subpart L), of the preamble to this rule. For a respons e to the comment regarding monitoring frequency, please see the response to comment nu mber EPA-HQ-OAR-2009-0927-0103.1, excerpt number

18.

Section 4.3.6.3 – Exemptions and Exclusions from Monitoring



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 20

Comment: All regulations that require equipment l eak monitoring have a de finition or threshold for the pollutant concentration in the pipe that is being monito red. Most rules use 5 wt% as the threshold for requiring monitoring, since emissi ons are trivial from components with low pollutant concentrations. Some rules use 10 wt %. Subpart L regulation does not specify a minimum threshold and thus any LDAR componen t with merely a trace concentration of an FGHG must be measured using Method 21. Method 21 instruments are not very sensitive to most FGHG compounds and, as a result, have excessi vely high response factors well above those

65allowed by Method 21. This means that monitori ng components with low concentrations of FGHGs will not detect these compounds and th us will only provide meaningless data and no

environmental benefit. DuPont recommends that Subpart L as well as Subpart O contain a more

definitive definition of “In FGHG service” a nd strongly recommend 5 wt% as the definitive

threshold for “in FGHG service.” Consistent w ith MACT standards (i.e., 40CFR 63 subpart H (40CFR 63.161), only light liqui ds should require monitoring.

Response: We agree with the commenter that th e equipment leak monitoring requirements should include several of the standard exemptions that are typical in other regulatory programs. It is reasonable to exempt streams with low fluorinated GHG concentrations because this exemption focuses resources on those pieces of equipment that are likely to emit fluorinated

GHGs. The definition of “In fluor inated GHG service” has been re vised to include those pieces of equipment that contain or c ontact a liquid or gas that contai ns at least 5 percent by weight

fluorinated GHG.

In revising the equipment leak monitoring require ments to allow multiple alternative monitoring and emission estimation techniques, we also re viewed the requirements in other regulatory programs and incorporated typical monitoring excl usions and exemptions. The commenter also noted that only those pieces of equipment in light liquid service should require monitoring. We have revised the rule to include monitoring only for those pieces of equipment in light liquid service and those in gas and vapor service, if the facility monitors individual pieces of equipment rather than relying on room air m onitoring approaches or default em ission factors.. An exclusion from monitoring pieces of equipment in heavy liquid service has been incorporated into the final rule; however, facilities must estimate emissi ons from pieces of equipment in heavy liquid service using another approach (e .g., application of default emissi on factors). In previous rulemaking efforts, EPA excluded pumps, valves, conn ectors, and agitators in heavy liquid service from routine monitoring on the basis that they contribute only a very small portion of overall emissions from a process unit (see 57 FR 62680; December 31, 1992). For this reason, we have excluded the heavy liquid service from monitoring requirements.

Several other types of equipment are also exclude d from requirements to perform individual leak monitoring because they have specia l features that limit emissions from leaks. However, as is the case for equipment in heavy liquid service, th e facility must still estimate emissions from these types of equipment using another appr oach. The following types of equipment are excluded: (1) pumps and agitators that have dual mechanical seals; (2) pumps and agitators with no external shaft, (3) pressure re lief devices in gas and vapor se rvice that have upstream rupture disks, (4) sampling connection sy stems with closed-loop systems or closed-purge systems, and (5) any pieces of equipment where the leaks are routed to a closed-vent system to a control device or destruction device. Equipment with dual mechanical seals is less likely to leak since it has two seals rather than one, and pumps and agitat ors with no external shaft will not be able to leak through a shaft opening. For pressure relief devices with an upstream rupture disk, visual inspection can detect a ruptured disk, which can be replaced, or can confir m the presence of an unruptured disk. Sampling c onnection systems have been excluded from monitoring requirements because they typically have clos ed-loop system or closed-purge system, so no purge material would be released (we would like to note that the valves and any open-ended line in the sampling loop would be subject to mon itoring or other emission estimate methods). The

66final rule also excludes from monitoring any piece s of equipment where the leaks are routed to a closed-vent system to a control device or destru ction device because these leaks are not subject to monitoring in other rules, a nd the control is expect ed to reduce actual emissions to low levels. Again, facilities must estimate emissions from th ese types of equipment using another approach. This approach may incorporate leak events, repa ir, or replacement events for these pieces of equipment that may occur over the year.

EPA has allowed use of the default Average Emi ssion Factor approach from EPA’s Protocol for Equipment Leak Emission Estimates, EPA-453/R-95- 017 (EL Protocol) in the final rule, but we noted that there is no average emission factor available for instrumentation systems or for pressure relief devices in liqui d service. We have therefore exempted these equipment types from the equipment leak requirements. In previous rule-making efforts, EPA determined that instrumentation systems consist of small diameter tubing and equipment in confined areas that are not easily monitored, that in strumentation systems are subject to frequent surveillance and maintenance so any leaks are readily detected an d promptly repaired, and that the integrity of instrumentation systems is checked after repair or maintenance. Therefore, the total mass of emissions from instrumentation system leaks is expected to be small (see 57 FR 62680; December 31, 1992). Pressure relief device in lig ht liquid service or heavy liquid service were also determined to contribute only a ve ry small portion of overall emissions.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 25

Comment: Current LDAR regulations also specify that facilities must monitor components in

service not less than 300 hours per year and containing not le ss than 5% of the regulated constituent. EPA should add these provisions, or directly adopt the entirety of 40 CFR 63 Subpart H or UU as an appropriate compliance option.

Response: We agree that an exemption for pieces of equipment in serv ice less than 300 hours per year is appropriate and is consistent with exemptions in other regulatory programs. The final rule includes an exemption from monitoring for pieces of equipment in service less than 300 hours per year.

For a discussion of the concentration that de fines equipment as be ing “in fluorinated GHG service, please see the response to comme nt number EPA-HQ-OAR -2009-0927-0103.1, excerpt

20.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 23

67Comment: We recommend that this subpart, as well as subpart O, contain a more definitive definition of “in fluorinated GHG service” and strongly recommend that 5% by weight be the definitive threshold for “in fluorinated GHG service.” Consistent with NESHAP standards, only light liquids and actual gasses should require monitoring.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 20.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 22

Comment: As written, this section does not spec ify a minimum threshold for measuring EL from fluorinated GHG emissions, and therefore requires that any component with a trace

concentration of a fluorinated GHG must be measured using Method 21. Method 21 instruments are not very sensitive to most fluorinated GHG compounds and, as a result, have excessively high response factors well above those allowe d by Method 21. This means that monitoring components with low concentrations of fluor inated GHGs will not detect these compounds, resulting in no reportable emissions and thus no environmental benefit.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 20.



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 19

Comment: The Subpart L Equipment Leak Monito ring provisions are missing key provisions typically found in LDAR programs. EPA: Section 98.123(c) states: “If you comply with paragraph (b) of this section, you must calculat e the fluorinated GHG emissions from pieces of equipment associated with processes covere d under this subpart and in fluorinated GHG service.” Comment: The Subpart L Equipment Leak Monitoring provisions do not include provisions and exclusions for unsafe to monitor lo cations, insulated equipment, and equipment in vacuum service. These provisions are applicable to Subpart L Equipment Leak Monitoring, and should be incorporated. They are not referen ced in Method 21. EPA can refer to the SOCMI MACT LDAR regulations; for exampl e provisions (40CFR 63 subpart H).

Response: We agree that an exclusion from mo nitoring for pieces of equipment that are difficult-to-monitor, unsafe-to-monitor, or insulate d is appropriate and is consistent with other regulatory programs. The final rule includes an exclusion from m onitoring for pieces of equipment that are difficult-to-monitor, unsafe-to-m onitor, or insulated; however, facilities must estimate emissions from these pieces of equipment using another approach.

68

### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 30

Comment: EPA does not include provisions for repor ters to manage com ponents that are not easily monitored or cannot be monitored at all using current techniques in this proposal. Existing LDAR provisions concepts include “difficult to monitor” and “unsafe to monitor” to manage components that are installed more than two meters above a working surface or cannot be reached safely during operations due to operational hazards. Arkema operates a FGHGcontaining manufacturing process that operates at high pressures (hundreds of pounds per square inch) where no employee, contractor, or visito r may enter the operating area during production. Compliance with an instrument LDAR program during FGHG operations in high pressure service units would violate Occupational Safe ty and Health Administration (“OSHA”) process safety management (“PSM”) regulations at 29 CFR 1910.119. Alternate LDAR monitoring protocols, including no monitoring, s hould be available to reporters.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 19.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1

Comment Excerpt Number : 24b

Comment: This section should also de fine “difficult to monitor” and “unsafe to monitor” to provide reporters with relief from monitori ng components that would not be monitored in existing LDAR programs. For example, 40 CFR 63.1022(c) provides a procedure where reporters may show that components are inaccessibl e, due to height from a working surface or location behind a blast wall. Many fluorochemical manufacturing units operate under substantial pressure, where personnel are not permitted to enter the process unit during unit operations. Insome cases, the only viable method to calculate fluorinated GHG emissions from some safetyrestricted process units is to utilize the “av erage” factors from the 1995 EPA LDAR guidance document. We have provided additional technica l comments on this section in the attached Appendix B.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 19.



### Commenter Name: Dave Stirpe


### Commenter Affiliation: Alliance for Responsible Atmospheric Policy

69

### Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number : 12

Comment: The Alliance is concerned about the limite d options provided in the Proposed Rule, including the lack of any diffi cult-to-monitor or unsafe-to-monito r provisions and the lack of pressure leak checking protocol s in the Leak Detection and Re pair (LDAR) reporting proposal.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 19.



### Commenter Name: Jeff C. Muffat


### Commenter Affiliation: 3M Center


### Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 20d

Comment: 2. We would request that any requirement for equipment leaks be properly aligned with the regulatory thresholds for source category testing. Equipm ent leak testing should not be required for processes with vent emissions that are below the one (1) ton/yr threshold.

Response: We have not included a mass-based thresh old for equipment leak testing. Equipment leak monitoring requirements under other regulatory programs typically in clude a concentrationbased threshold that is applicable to individual streams rather than exempting an entire process.

We have included a concentration-ba sed threshold in the final rule.

Please see the response to comment nu mber EPA-HQ-OAR-2009-0927-0103.1, excerpt 20.

Section 4.3.6.4 – Frequency of Equipment Leak Monitoring



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 18

Comment: Equipment Leak monitoring frequencies in §98.123(c) are not stated in the rule. EPA: Pages 18676-18677 and 18679 of the preamble state that equipment leaks will be monitored annually using Method 21 . Comment: The monitoring fre quency is not stated in the rule. Method 21 does not specify a frequency. Few FGHG processes currently monitor flanges since few FGHGs are HAPs, and VOC LDAR re quirements generally do not require it. Hazardous Air Pollutant monitoring requirement s are generally on a 2 year frequency for flanges. An annual requirement to monitor e quipment exceeds VOC and HAP requirements, and is excessively costly and burdensome. A more a ppropriate requirement woul d be to set the leak frequency on performance, but keep the frequencies common to reduce complexity for instance: >1 % – testing every year; >0.5% but <2 % - testi ng every 3 years; <0.5% - testing every 5 years.Since this monitoring pertains to emissions estimations – statistically based sampling of “sub70lots” of equipment leak points is a valid, more cost effective means of emissions determination. Please refer to Appendix B for more detailed comments on sub-lot sampling.

Response: We have clarified in the final rule that, for facilities that conduct equipment leak monitoring, the monitoring must be conducted annually, but that it may be conducted on a representative subset of the pr ocess equipment each year. Specifi cally, the rule requires that a representative one-third of the pi eces of equipment be monitored each year so that at the end of 3 years, all pieces of equipment have been monitored. If the facility has multiple processes that have similar types of equipment in similar se rvice, and that produce or transform similar fluorinated GHGs (in terms of chemical compos ition, molecular weight, and vapor pressure) at similar pressures and concentrations, then the fa cility may annually sample all of the equipment in one third of these processes rather than one th ird of the equipment in each process. The data from these representative equipment pieces may be extrapolated to the remaining equipment to estimate annual emissions for equipment leaks. While monitoring frequencies vary across LDAR programs based on the type of equipment and the site-specific leak rate s, the annual monitoring requirement, with one-third of equipment pieces m onitored each year, for subpart L is relatively consistent with the frequencie s required in other programs.



### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 22

Comment: Pages 18676-18677 and 18679 of the preamble st ate that equipment leaks would be monitored annually using Method 21 . This frequency requirement is not stated in the rule and Method 21 does not specify a frequency. Few fluorinated GHG processes currently monitor flanges since few fluorinated GHGs are haza rdous air pollutants (HAPs), and VOC leak detection and repair (LDAR) requirements generally do not require it. HAP monitoring requirements are generally on a 2 year frequency for flanges. An annual requirement to monitor equipment exceeds VOC and HAP requirements, and is excessively costly and burdensome. We recommend that the requirement be biennial monitoring of equipment l eaks, excluding those from non-rotating equipment such as flanges, using a procedure that is detailed in a facility’s GHG Monitoring Plan.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0103.1, excerpt 18.

Section 4.3.6.5 - Other



### Commenter Name: John Dege


### Commenter Affiliation: DuPont


### Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 21

71Comment: DuPont supports EPA’s di stinction between “Equipment Leaks (EL)” and “Leak Detection and Repair (LDAR)” since the “repair” portion of the common acronym is not in scope. EPA: EPA is proposing that monitoring of process vents be supplemented by monitoring of equipment leaks...” Comment: DuPont supports EPA’s proposal to exclude the repair portion of LDAR in the equipment monitoring provisions.

Response: We appreciate the commenter’s support and ag ree that since this is a reporting rule, a focus on monitoring for the purposes of “leak dete ction” for estimating emissions is necessary. Requirements related to the “and repair” portion of LDAR have not that been included as full LDAR requirements would be cons idered a control requirement.



### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 54

Comment: In proposed §98.127(f), EPA details the reco rds associated with equipment leaks for which affected facilities are required to main tain. EPA only proposed to require reporters to maintain records associated with equipment leaks (i.e., number, type, service of components; process stream composition; screening data). Su bpart L does not require reporters to maintain repair records for leaking equipment. Fugitive emissions records without repair records only provides a limited view of actual emissions. Proper actual emissions calculations require repair records to allow reporters to use the post-repair LDAR measurements to calculate point-forward actual emissions. EPA should require a consistent view of LDAR related FGHG emission rates.

Response: We have not included an explicit requirem ent to keep records of leak repairs in subpart L. The final requirements allow mu ltiple approaches for equipment leak emission estimation, and some of these may not assign lowe r leak rates to equipment following a repair. However, §98.3(g)(2) requires that facilities keep r ecords of “the data used to calculate the GHG emissions for each unit, operation, process, and activ ity, categorized by fuel or material type.” These data include, at §98.3(g)(2) (i), “the GHG emissions calculations and methods used.” Under this provision, facilities that assign a lower leak rate to equipment following a repair will be required to keep records of the repair to document the chan ge in the rate.

Section 4.4 - Allow Combination of Mass Balan ce, Process Vent testing and Engineering

Calculations



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 1

Comment: The following comments on EPA’s propos ed Subpart L of the GHG Mandatory Reporting Rule (MRR) provide a more detailed de scription of our suppor t and concern for many

72of the issues involved with the calculation, m easurement and reporting of fluorinated greenhouse gases. We are concerned that Subpart L is still very prescriptive as re-proposed, and prescribed calculation and monitoring methods remove the ability for sources to develop new protocols that

better calculate the emissions from our facilities. Affected sources should be allowed to develop site-specific protocols for emissions estima ting, measuring and monitoring, and detail such protocols in the requir ed GHG Monitoring Plan.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 1.



### Commenter Name: Brian R. Keck


### Commenter Affiliation: Air Products and Chemicals, Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 22

Comment: In Section B.7 of the T echnical Support Document (TSD), EPA notes that some facilities use a form of the mass balance approach in conjunction with an emissions factor based approach to track yields and changes in the pr ocess, as well as to calculate emissions. Air

Products recommends that this “combined ma ss balance emission factor” approach be an emissions estimation method that a facility co uld propose for EPA’s cons ideration and approval in lieu of the current mass balance, process-vent -specific emission factor or process-vent-specific emission calculation factor approaches.

Response: The commenter suggests here that perhaps a “combined” mass balance and emissions factor approach could be used for estimating emissions. We have not included such an approach in the final rule as it is not clear how such an approach could be constructed. The risk of a combined approach would be that it woul d either overlook or double-count some emissions. We would like to clarify, however, that each sepa rate “process” may use either a mass balance or an emission factor approach. For example, the production of each isolated intermediate is defined as a separate process; t hus, a facility may use the mass ba lance approach for one isolated intermediate (process), and then use an emission factor approach for the next isolated intermediate (process). We would also like to no te that even within a process, there may be situations in which, if the process itself can be broken apart, by unit operation for example, with clean separation between the tw o, a mass balance approach coul d be used for the first unit operation and an emission factor could be used for the second unit operati on, or vice versa. A so-called “combined” approach, however, that is part mass balance and part emission factor

would not be allowed.



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 16

73Comment: EPA should also consider ways to meld these approaches. Process vent

measurements can serve as a us eful way of checking mass-balan ce emissions estimates. As the TSD describes, “[f]acilities that use a form of th e mass balance approach indicated that it is often used in conjunction with an emissions factor ba sed approach, to track yields and subtle or incremental changes in the process.” 12 It may be possible to co mbine these processes here, perhaps by requiring facilities using the mass bala nce approach to check their results using process vent measurements every five years.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 22. In addition, please no te that in the final rule, f acilities using the mass balance approach are required to characterize emissions from process vents by either (1) assuming that

all emissions of fluorine occur in the form of the fluorinated GHG that has the highest GWP among the fluorinated GHGs that occur in more than trace concentrations in the process, or (2) using previous or new emission measurements to assign missing mass to reactant, by-product, and/or product emissions, as appr opriate. For larger processes w ith emissions equal to or greater than 25,000 mt CO 2 e, facilities would be required to conduct measurements for certain large process vents, use existing measurements for ot her process vents, and make assumptions about fugitive emissions based on the contents of vented emissions.

Section 4.5 - Other



### Commenter Name: G. Auth


### Commenter Affiliation: MIDAC Corporation


### Comment Number: EPA-HQ-OAR-2009-0927- 0074.1 Comment Excerpt Number : 1

Comment : Executive Summary. Fourier transform in frared spectroscopy (FTIR) as used in continuous emission monitoring (CEM) is a well -established and mature technology. FTIR CEM is currently used both in the electronics indus try and in the F-gas ma nufacturing industry. The

hardware and software are read ily configurable to a range of applications, and the sampling equipment is sufficiently resistant to the corrosive components expected in these process gas streams (e.g. HF, F 2 ) that they operate for months at a time with little or no evidence of damage. Several applications are describe d where FTIR CEM can be utilized at various locations within the facility to cost-effectivel y monitor GHG gases as required.

FTIR spectroscopy is used for both qualitative a nd quantitative analysis of a wide variety of compounds. FTIR spectroscopy has been in use for over 40 years and is a well-established technique, common in labs, academia, and industry worldwide. The use of FTIR as a continuous

emission monitor is likewise we ll-established and widely used – 40 CFR Part 60, Appendix B, Performance Specification 15 - Performance Sp ecification for Extractive FTIR Continuous Emissions Monitor Systems in Stationary Source s. This technology is very mature and can be readily used in CEM applications for the electronics and F-gas manufacturing sectors.

12 Fluorinated Gas TSD at 22.

74FTIR for Component Analysis. The gases described in the EPA Proposed Rule (CF 4 , C 2 F 6 , C 3 F 8 , c-C 4 F 8 , c-C 4 F 8 O, C 4 F 6 , C 5 F 8 , CHF 3 , CH 2 F 2 , NF 3 , SF 6 (F-GHGs) and N 2 O) all have unique infrared spectra and can be r eadily distinguished in the pres ence of the others with high resolution FTIR spectrometers (1.0 - 0.5 cm -1 ). The instrumental and data collection parameters spelled out in the 2006 ISMI Guideline for E nvironmental Characterization of Semiconductor Process Equipment are generally adequate to measure these compounds in an FTIR CEM application. Similarly, byproducts of F-gas deco mposition or reaction as might be observed in these industries (e.g. COF 2 , OF 2 , SO 2 , SOF 2 , SO 2 F 2 , etc.) are also readil y distinguished. A single infrared spectrum can be analyzed for any comb ination of these component gases. As an FTIR collects the entire infrared sp ectrum simultaneously, the identitie s and concentrations of these compounds can also be determined simultaneous ly. Note that this is not the case with nondispersive infrared spectrosc opy (NDIR). An FTIR collects the entire spectrum, and the compounds of interest are quantif ied immediately. This process can be repeated continuously and indefinitely (months or years), limited only by equipment failure or data storage capacity.

Another example of FTIR as a CEM is in mon itoring for products and byproducts in a large FGHG manufacturing facility in the US Midwest. At this installati on, there are 5 separate FTIR spectrometers monitoring separate processes in a continuous manner for months at a time. These spectrometers operate with compounds in the percen t concentration range, so the sample cells are much shorter; 1 cm, 5 cm or 10 cm long as n eeded by the specific process. This application observes starting materials and products as well as corrosive byproducts such as HF. The sample cell is the only component that contacts the corrosive environment, so corrosion-resistant componentry is only required for a small portion of the equipment. This can be a sample cell comprised of PTFE, solid nickel, nickel coated aluminum, or 316 stainless steel, capped with zinc selenide (ZnSe) windows. In the case of a long-path gas cell, the hardware would include ZnSe, germanium, or diamond windows and gold-coated or polished nickel mirrors. These components are readily available and are not harm ed by harsh environments such as these. The FTIRs and gas cells utilized at this installation are examined and cleaned on a quarterly basis

with no evidence of corrosive a ttack or damage. The concern noted on page 122 of the Preamble is unfounded when the correct hardware is specified, as based on MIDAC Corporation’s experience with such applications. Th is equipment will even withstand Cl 2 , HBr, and F 2 as observed in silicon etch and NF 3 -based chamber clean processes.

Pre-POU Scrubber CEM. The sample line extrac ts gases for analysis immediately after the process vacuum pump but before the POU abatement scrubber. This configuration would require a short-path gas cell (1 – 10 cm) as the target gases will likely be in the 0.1% (10,000 ppm) range or greater. A high-speed Sterling-cooled me rcury-cadmium-telluride (MCT) detector is recommended as the process composition changes quickly and data points should be no more than 3-5 seconds apart. In this case, a single sa mple line would be monitored for a predetermined period (e.g. a couple of minutes) so the entire wa fer can be analyzed before moving on to the next sample chamber. This configuration is useful for fingerprinting emissions from a representative process (e.g. dielect ric etch or chemical vapor depos ition) to determine emissions factors according to the ISMI Sematech Protocol . This configuration is too equipment-intensive for every process chamber as there may be a thous and process chambers in a large fab. An FTIR CEM for each process chamber is not economically feasible for an entire manufacturing facility. However, one or two sample lines may be used on representative chambers (e.g. silicon etch,

75dielectric etch, nitride etch, then deposition) to fingerprint specific processes. In addition, this configuration may be used by a process tool ma nufacturer for determining emissions factors. This configuration may also be considered for an F-gas manufacturer (Subpa rt L) in determining byproducts and stoichiometric factors from the manufacturing process.

Duct or Sub-main CEM. In th is configuration, samples are take n from specific locations in submains where GHGs may be expected, such as an oxide etch bay, or in an extracted area around an F-gas manufacturing vessel or valve system (m onitoring for leaks). In these ducts, the target gases will be more dilute as other equipment, such as gas cabinets, may also be feeding into these lines. In such cases, a longer path gas ce ll (e.g., 20 meters) is indi cated, along with an MCT detector. Under such conditions, detection limits to the single ppb levels may be achieved for most fluorinated gases. This c onfiguration would also require dilution spiking capability using

CF 4 , SF 6 , or ethylene 13 , or a QMS and a tank of Kr with an MFC at some location upstream ofthe sample point. The CEM software can be configured to open and close a valve on a predetermined schedule to allow the spiking gas into the duct for real-time dilution analysis. This configuration would be used to maintain a record of emissi ons by sub-main which can be integrated and reported in kg CO 2 E/year or other desired units.

Stack CEM. In this configuration the samples are taken from the exha ust stacks on the roof,

such as at the exit of a thermal oxidizer or rooftop scrubber. The concentrations of the FC gases will be very low at this point, and the ability to reliably see con centrations in the low ppb levels is imperative. This configurati on would utilize a 20- or 60-mete r gas cell and an MCT detector. Heated lines and gas cell are also required. These components would maximize the absorbance of the fluorocarbon while allowing for many coadded scans to enhance the signal-to-noise ratio, both of which may be required for ve ry low concentrations. One ppb of CF 4 from a 100,000 cfm stack will contribute 22 kg CO 2 eq/day, so sensitivity is paramount in this application. This will be the most challenging of the described applicati ons due to the very low concentrations of gases expected at the stack.

Expenditures. The cost of an FTIR CEM syst em is very dependent on the number of data collection points and other aspects of the configuration (pathlength of gas cell, type of detector, room-temperature or heated gas cell, etc.). The price of a fully-outfitted FTIR CEM system can be comparable to (or less than) what a large fa b might spend in a year for on-site testing by a third-party analyst. The proposed 20% of the fab’ s POU scrubbers could be sampled for the first year at this initial CapEx and installation price, then the sample lines can be moved to different scrubbers the second year at minima l cost to the fab, and so forth.

Summary. FTIR for continuous emission monitoring of a wide range of i ndustrial processes is a

mature and well-established tec hnology. The dilution levels and corrosive nature of the gases

used in the semiconductor and rela ted industries are well within th e capabilities of FTIR CEM to measure reliably for extended periods. FTIR is suitably configurable that an FTIR CEM can be

13 Ethylene (CH2=CH2) is an inexpens ive hydrocarbon gas of minimal toxic h azard (simple asphyxiant). It is used extensively in the FTIR community as a calibration transfer st andard or tracer. Ethylene has a very sharp and distinct peak at 950 cm -1 and is commonly used as a spiking gas in the FTIR industry. Though the primary ethylene Qbranch band may observe some interference from SF 6 (945-948 cm -1 ), ethylene has other bands away from common FCs and other interferents that can also be used for quantification.

76cost-effectively utilized in a wi de range of semiconductor- and F- gas related applications, though as with any technology, there are limitations. FTIR CEM is a suitable technology for analysis of GHGs from both the electronics (S ubPart I) and F-gas manufactu ring (SubPart L) industries.

Response : Based on the comment letter, we are aware of one fluorinated gas facility that has CEMS installed. Although some technologies (e.g., FTIR) may permit continuous monitoring of fluorinated GHG emissions, we do not have sufficient informati on on the cost of outfitting a facility with this technology to m eet the objectives of the reporting rule to require them at this time. We will continue to evaluate the possible use of CEMS at these facilities in the future.

EPA appreciates the useful information provi ded on FTIR CEMS for the fluorinated gas production industry. The commenter cited examples of FTIR CEMS installations, showing that the monitoring systems are available and applicab le for certain applications. The commenter cited one fluorinated gas production facility that is monitoring 5 streams. As other commenters state, many facilities in the fluorinated gas sour ce category do not have CEMS installed on their process vents. The commenter noted a number of t echnical features and i ssues, noting that units

can be made of corrosion-resistant materials for corrosive environments, that concentrations of varying magnitudes can be addressed with path length selection (e.g., approximately 1 cm to 60 meters with path length increasing with decreas ing fluorinated gas concen trations), and use of sophisticated detector cooling approaches may a ddress the analysis speed. The fluorinated gas production source category is a diverse and complic ated industry, with ma ny different types of processes and emissions. We are certainly aware th at HF concentrations vary significantly from facility to facility depending on the process, and wh at might be technically fe asible at one facility may not be feasible at another. (One facility has noted in conversations with EPA that they attempted to use an FTIR CEMS in the past w ithout success.) Industry has noted concerns with monitoring of hazardous streams.

Prior to requiring CEMS, additiona l information is needed to determine the costs for an FTIR CEMS, particularly for CEMS that could a ddress the very corrosive environments and complexity (including the number of sample locati ons) that would be required for many facilities and processes in this source cate gory. These costs would need to be considered in conjunction with the expected increase in the accuracy and pr ecision of the emissions estimates and the goals of this reporting rule.



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 18

Comment: We recognize that many facilities do not have continuous emissions monitoring systems (“CEMS”) installed, and that acidic gase s may make it difficult to use such systems without scrubbers. Nonetheless, CEMS, as EPA acknowledges, “would be expected to provide estimates of emissions more accurate than either the mass-balance or process-vent approach.” 14

14 75 Fed. Reg. at 18,679.

7778 EPA should employ these methods for the largest f acilities and emissions streams. The agency proposes requiring CEMS for streams resul ting in the emission of more than 50,000 mtCO 2 e annually. We strongly support this proposal. Th ese individual streams have climate-forcing effects as large as that from entire factories in some instances, and should be closely monitored using the best technology available.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0074.1, excerpt 1.



### Commenter Name: Craig Holt Segall


### Commenter Affiliation: Sierra Club


### Comment Number: EPA-HQ-OAR-2009-0927- 0128.1 Comment Excerpt Number : 14

Comment: EPA allows facilities to select either a mass-balance or emissions factor-based monitoring approach. 15 As we discuss below, continuous emissions monitoring would be the better choice, at least for larg e sources. But if EPA instead uses these approaches, it should improve their implementation.

Response : Please see the responses to commentnumber comment number EPA-HQ-OAR2009-0927-0128.1, excerpt 15, and commen t number EPA-HQ-OAR-2009-0927-0128.1, excerpt 17.

15 See Prop. 40 C.F.R. § 98.123Section 5 - Monitoring and QA/QC Requirements

Section 5.1 - Initial Scoping Test

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 13

Comment: §98.124 (a), Initial scoping test for fluorin ated GHGs. 3M believes that the initial scoping test for fluorinated GHG’s that is described in §98.124 (a) may be unnecessarily prescriptive with respect to requiring gas testing for all streams. In addi tion we are also providing comment on the analytical costs a nd technical feasibility of identif ying all chemicals that may be present at concentrations of greater than 0.1%. We believe that this requirement can be modified to allow greater flexibility in the manner in wh ich these assessments are made. In addition, if EPA chooses to maintain this requirement, the thre sholds that require such an analysis should be aligned with the emission thresholds that are li sted in the rule. Finally, 3M is also providing

comment on the referenced test methods in this section.

There are many methods that may be used to determine the composition of a gas stream. They would include process and product knowledge, testing conducted at other locations, historical testing, and in many cases, combinations of all of these methods. There are many examples where process and product knowledge would precl ude the need for vent gas testing. Emissions that may occur during head space displacement or the final filtration of a product are examples where sufficient product knowledge is available a nd no additional testing would be required. In these cases, an analysis of the process fluid will provi de sufficient information to characterize the materials that will be present in process emissions. In some cases, knowledge of process chemistry, even when reactions occur, will be adequate to determine vent gas composition especially when testing has already been conduc ted on similar materials. Research and process development specialists with knowle dge of the process chemistry can typically identify the types of byproducts that will be generated in the process.

Testing that is conducted either in the laboratory or at the pilo t plant should be adequate in identifying the types and quantitie s of materials that are present in full-scale manufacturing units. In addition, sample collection a nd analysis may be greatly simp lified due to the size of the process streams and proximity to the division’s centralized analytical fa cilities. During 3M’s commercialization process for new products, anal ysis may be conducted for various product and byproduct streams. In 3M’s Chemical Process Development Center (CPDC), the manufacturing schemes are normally carefully designed so as to properly duplicate f actory operating conditions.

3M believes that information that is generated at any of these fac ilities will be representative of factory operations. Testing conducted in similar manufacturing operations elsewhere should also

be sufficient.

Finally, 3M has completed a si gnificant body of emissions sour ce testing as a part of the development of its corporate greenhouse gas inventory. 3M has completed a corporate GHG inventory since 2002. The methodologies have been va lidated in two rigorous third party audits

79using EPA approved companies. The inventory incl udes a calculated overall uncertainty that has been determined using rigorous sta tistical techniques. Data generate d has a part of this work has been provided to the EPA Climate Leaders program since 2003. Much of this work dealt with the identification of the chemistry that was present. This work has already allowed 3M to confirm its knowledge of process stream contents. Much of the scoping analysis has already been completed.

The analysis provided in Att achment 1 provides a good example where a scoping analysis would not be necessary for different t ypes of products. In this case there are a limited number of raw

materials that are added in diffe rent quantities. Any products or byproducts that are present in this process would also be the same.

Because there are so many different methods and combination of methods that would be employed to meet the requirements of this section, 3M be lieves that it would be inappropriate to specify a single approach. We acknowledge that the regulated entity has an obligation to exercise a standard of care in its analys is of air stream contents and to properly document the methods

that were used to make these assessments. We believe that such assessments would be conducted, captured in a written document as desc ribed in the facility’s GHG Monitoring Plan, and retained in the facility record. We believe th at the diversity of methods that may be used in the assessments can be captured in simple cha nges to the language in §98.124 (a) by substituting the word “analysis” for “test”. (a) Initial sc oping analysis for fluor inated GHGs. You must conduct an initial scoping analysis to identify all fluorinated GHGs that may be generated from processes that are subject to th is subpart and that have uncontro lled emissions (i.e., pre-control emissions levels) of 1.0 metric ton or more of fluorinated GHGs. For each process, you must conduct the initial scoping analys is on the stream(s) (including process streams or destroyed streams) or process vent(s) that would be expected to individually or collectively contain all of the fluorinated GHG by-products of the process. Initial scoping analysis must be conducted according to the procedures in paragraph (c)(4)(v) of this section.

In addition to the above, 3M believes that any “testing” requirement shoul d be aligned with the regulatory thresholds that are be ing established in the rule for source testing. In most cases, a “scoping test” would be conducted as a part of the stack testing project and not as a separate activity. Prior to any facility emission test, proc ess chemistry will typically be reviewed with the appropriate experts. The testing methods employed in the field will be based on these reviews, but contingent measures (such as canister sample collection) are employed to verify vent stream composition.

Procedures for chemical analysis are referen ced in §98.124 (c)(4)(v) and our comments on these

methods are contained in that section.

Response: EPA is retaining the proposed requirement to sample and analyze process streams or process vents to identify the fu ll set of fluorinated GHGs that are generated by the process. Consequently, EPA is not adopting the broade r term “scoping analysis” suggested by the commenter, although EPA is changing the term “sc oping test” to “scoping speciation” to clarify that stack testing is not required.

80The initial scoping speciation re quirement (“scoping test” in th e April 2010 proposed rule) is designed to ensure that faciliti es identify all fluori nated GHGs that are released from their process. Facilities can then use this information to better inform their emission estimates, e.g., to identify the set of fluorinated GHGs to include in emission testing and emission characterization

measurements. Most facilities have indicated that their prio r scoping measurements have been performed on pilot-scale processes or laboratory- scale processes instead of a full-scale process; however, EPA has concerns that these data may not reflect the actual compounds that are present in the streams. As noted in the preamble of April 2010 proposed rule , some fluorinated gas producers have stated that they found compounds in the full-scale process that they did not find in the pilot- or laboratory-scale processes. In some cases, this may have occurred because the analytical methods used at the pilot- or laboratory- scale were not sensitive enough to detect fluorinated GHGs that were present at low (but still higher than trace) concentrations; in other cases, it may have occurred because subtle di fferences between the laboratory- and full-scale processes led to the generation of new or different by-products.

In the final rule, EPA is clarifying that if a facility has prev iously conducted measurements on full-scale processes to identify fluorinated GHGs that meet the requireme nts in §98.124(a), these data may be used to satisfy the subpart L initial scoping speciation requirements. These previous measurements may be used if conducted less than 10 years prior to the effec tive date of the rule. The initial scoping speciation is not intended to quantify emissions but is intended to identify compounds, and this has been clarified in the fi nal rule. However, a facility may conduct the initial scoping speciation in conjunction with the emi ssions testing (or emission characterization), as a combined act ivity, if the streams or process vents selected for testing meet the requirement for being likely to contain all the fluorinated GHGs generated by the process,

and if the measurements are sens itive enough to detect fluorinated GHGs that occur anywhere in the process above trace concentrations. The final rule includes requirements for making measurements on the full-scale process to identif y the fluorinated GHG present. In order to minimize the burden placed on facilities, EPA is only requesting that those streams or process vents that are most likely to c ontain all fluorinated GHG by-products and products present in that particular process be analyzed, e.g., could be a single stream or tw o or three streams. We have

clarified in the rule text that f acilities are not required to test every stream or process vent, and facilities may certainly test upstream process streams to identify compounds.

EPA has included revised sampling and analytical methods in §98.124(e) to allow facilities to select appropriate, validated methods (incl uding validated, industry-accepted methods) and to document their use in the facility GHG Monitoring Plan. The initial scoping speciation does not have to be conducted using EPA emission testin g or stack testing re ference methods; other methods meant for process stream sampling and an alysis may also be used, as the facility identifies streams most likely to individually or collectively contain all the fluorinated GHGs generated by the process. These measurements may be taken upstream for process streams or for process vents, at any location that provides significant concentration of the fluorinated byproducts present. Certainly contingent methods that the commenter refers to that meet the requirements in revised §98.124(e), i.e., the me thods have been validated, may be used.

EPA has established a threshold to limit the initial scoping speciation requirement to those processes that have at least one process vent that has uncontrolle d emissions of 1 mt fluorinated

81GHG per year. This is a change from the April 2010 proposed threshold which was 1 mt fluorinated GHG emitted from the process. The re vised threshold is on a process vent basis to make it more consistent with the process vent threshold for emission factor development, and does not require consideration of equipment leak emissions that would be included for a processbased threshold. The initial scoping speciation threshold ha s been based on the mass of

fluorinated GHGs rather than a CO 2 e limit to address the possibility that facilities may currently

assume that emissions occur in the form of one fluorinated GHG when they actually also occur in the form of another, currently unidentified fluorinated GHG. In such cases, a preliminary GWP weighting would yield an incorrect estimate of CO 2 -equivalent emissions from the process

vent.

Commenter Name: Ross Smith

Commenter Affiliation: PCS Phosphate Company, Inc

Comment Number: EPA-HQ-OAR-2009-0927-0084.1 Comment Excerpt Number : 3

Comment : The scoping requirement would be requi red to determine which fluorinated GHGs are emitted from all vents and emission points at the facility. The scoping test requirement will impose more cost burden on the facility without providing a significant amount of value. Many engineering and process studies have been performed documen ting what fluorinated compounds are emitted during the manufacturing process and this test is redundant of these activities. The test is also required as a one-time activit y, and depending on the pl ant configuration or formulation of materials, the emissions could differ and the test woul d no longer represent the emissions. This requirement should be removed from the proposal, as this information is already available from process engin eering studies and other widely accepted reference material concerning the manufacture of fluorinated materials.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13 and to comment number EPA-HQ-OAR-2009-0927-0128.1, excerpt 13.

Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 5

Comment: Allow methods other than those specifie d in §98.124(c)(4)(v) for the initial scoping study. The initial scoping study required under §98.124(a) must be conducted according to the procedures in §98.124(c)(4)(v). The procedures listed under §124(c )(4)(v) are extractive procedures (i.e., require that a sample of the str eam be extracted from the process and analyzed). Mexichem’s concern with these procedures is the potential for exposure to employees and/or contractors to HF and the ability of analytical equipment to properly func tion in the presence of HF. In addition, Mexichem’s production proce ss was not constructed with sampling ports appropriate for the methods provided. Additional time may be required to install appropriate sampling points (see comment 5 below). Mexichem requests that the agency allow the use of

82non-extractive engineering assessments for the initial scoping study.

Response: EPA recognizes the additional safety concer ns associated with the testing of streams

that contain HF. In order to address site-s pecific sampling and test ing issues and safety concerns, EPA has modified the language identify ing the permissible testing procedures (located in §98.124(e) in the final rule) to allow facilities to use an alternative testing procedure so long as it is quality-assured and capable of detecting the analytes of inte rest at the concentrations of interest. The scoping speciation is a one-time measurement, and facilities have until February 29, 2012 to complete it, which EPA believes will ge nerally provide adequate time to design and carry out sampling safely. However, where this is not the case, the best available monitoring methods (BAMM) provisions perm it facilities to request to us e BAMM for “unique and extreme

circumstances which include safet y, technical infeasibili ty, or inconsistency with other local, State or Federal regulations.”

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 28

Comment: The proposed scoping test in §98.124(a) is overly complex and in many cases, unnecessary. Chemical facilities typically know what compounds ar e present in factory streams. There are other methods, besides this proscribed scoping test, that facilities can use to determine the compounds present in factory streams. Vent stream contents may be determined by a variety of methods which include past information, me asurements involving processes with similar chemistries, and data obtained during bench scal e and pilot plants. Air Products appreciates our obligation to conduct due diligen ce to adequately understand our FGHG emissions content, but this requirement should more generally state the f acility will need to doc ument the methods that

were used to make this determination.

Section 98.124(a) requires the initial scoping test be performed by emission testing protocols in paragraph (c)(4)(v). Conducting the scoping study by stack test methods would be unnecessarily burdensome and costly. Some process vents with hazardous chemicals (HF, PFIB) are hazardous to test. When sampling these types of streams, the hazards can be multiplied because there might not be an existing sampling point. Also, some of the streams require a full acid suit and breathing apparatus for connecting and disc onnecting the sample cylinder. Th e sample systems that would be installed would most likely be 1⁄4” or 1⁄2” tubing manifolds th at would include connections for the sample cylinder itself but also ports for N 2 , solvent washout, vacuum, etc. To make and break these small connections while in an acid suit requ ires dexterity beyond that required for working with normal plant scale piping systems. For safe ty reasons, EPA needs to allow upstream process testing by validated, indust ry accepted methods to a ssess fluorinated GHG byproducts. Alternatively, Air Products also recommends that any standard GC/ECD, GC/MS, FTIR or similar analytical methods used to characterize the emitted constituents within five (5) years of the effective date of the final rule be acceptable, rather than having to conduct similar tests once again. Five (5) years following the effective date of the final rule, any emissions testing should be performed per the requirements and applic able methods specified in the rule, where

83practicable.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 2

Comment: 4. 3M has obtained a great deal of information on process emissions through previous testing. In addition, process gases are generally well characterized during the commercialization of new products. We endorse the intent of the “scoping” requirement and as a routine activity we have obtained this information. However, we believe that this information can be obtained through a variety of methods.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13.

Commenter Affiliation: Arkema Inc.

Commenter Name: Rich Raiders

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 45

Comment: EPA appropriately set a minimum th reshold for the proposed §98.124(a) scoping test. However, the 1 mtpy of uncontrolled FGHGs threshold should be increased. GWPs vary widely, and use of a GWP weight ed testing (based on typical GW Ps for FGHGs in use today) threshold would encourage low-GWP product deve lopment and marketing. EPA should modify proposed §98.124(a) to reflect a GWP-weighted 10,000 to 25, 000-mtpy CO 2 e basis per vent. EPA should harmonize testing levels with th e recently finalized GHG reporting rule. The reporting rule ramps down the level of scruti ny for prevention of si gnificant deterioration (“PSD”) permitting per 40 CFR 52. Likewise, EPA should consider allowing facilities to perform testing protocols on only th e larger sources (50,000 or 100,000-mtpy CO 2 e for the first two years, with smaller sources tested as the program matures and technologies improve.

Response: Please see the response to comme nt number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13.

Commenter: Brian R. Keck Organization: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 11

84Comment: In [section] B. Fluorinated Gas Producti on, Section 4, [of the re-proposal preamble] EPA requests comments on an alternative approa ch in which all fluorinated gas production facilities, regardless of their estimated pre- control emissions, would analyze their emissions using an initial scoping test proposed to ensure the facilities understand the identities, and therefore the GWPs, of the fluorinated GHGs poten tially emitted. Air Products recommends that

the list of GHGs contained in Table A-1 of Subpart A be the complete list of regulated GHGs

and GWP values.

Response : EPA has not adopted a no-threshold appro ach for the initial scoping speciation. We did not open the definition of fluorinated GHG to comment in this rulemaking; however please see the response to comment number EPA-HQ-OAR-2009-0927-0117.1, excerpt 2 for a discussion of how we have designed the requiremen ts of this rule to ensure consistency among facilities in how they monitor and report emissions of fluorinated GHGs that do not have GWPs listed in Table A-1 to subpart A.

Commenter Name: Craig Holt Segall

Commenter Affiliation : Sierra Club

Comment Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number : 13

Comment: We agree with EPA that facilities shou ld be required to conduct a scoping test identifying all fluorinated GHGs which they may emit, and that this te sting should be conducted

on emissions streams before control devices are applied. We generally agree it may be appropriate to exempt certain, very sm all emissions sources from this test.

We are less persuaded that this scoping test should be conduc ted only once in the life of a facility, as EPA proposes. Fluorinated gas producti on facilities are comple x chemical factories. Processes may change over time, equipment may change or corrode, and feedstocks may vary. These changes may, in turn, affect emissions. We ur ge EPA to therefore requi re periodic re-tests, either on at least a 5-year cycle or whenever a fa cility materially alters its processes, equipment, design, or feedstocks.

Response: Although physical or material changes to a process do not trigger a repeat scoping speciation under the final rule, EPA has captured these operating scenario modifications and the

effect on fluorinated GHG emissions by requiring facilities to revi sit (and if n ecessary, revise) emission calculation factors, emission factors, and emission characterizations (the emission measurements for the mass-balance approach) when operating scenarios are modified. The rule requires that emission calculation fa ctors be recalculated whenever they are affected by operating scenario modifications. The rule requires that emission factors and emission characterizations be updated through new emission test ing if the operating scenario modification results in a calculated fluorinated GHG emission factor change of 15 percent or greater. (For emission characterizations, this 15 percent change refers to a change in the percen tage of total fluorine emissions represented by any of the emitted fluor inated GHGs, that is, a change in the mixture rather than the magnitude. Changes in the ma gnitude are captured in the monthly (or more frequent) mass-balance measurements.) We al so include a general update requirement for

85emission factors and emission characterizations; facilities are required to conduct testing and revise the factor every 10 years.

Please see the response to comment nu mber EPA-HQ-OAR-2009-0927-0111.1, excerpt 15 for

more discussion of emission factor updates and their rationale.

Commenter: Brian R. Keck Organization: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 12

Comment: In [section] B. Fluorinated Gas Production, Section 5.b. [of the re-proposal preamble], EPA states that faciliti es would be required to sample the vents or streams that would be expected to contain all the fluorinated GHG by-products for the process using listed EPA and ASTM methods to identify fluorinated GHGs that occur in concentratio ns above 0.1 percent in emitted streams. This initial scoping must be performed by prescriptive and limited emission testing protocols. Conducting th e scoping study by stack test methods would be unnecessarily burdensome and costly. To avoid excessive testing and re-testing costs, Air Products recommends that standard GC/ECD, GC/MS, FTIR or similar analytical methods used by the

facilities on these vents or streams to characteri ze the emitted constituents within five (5) years of the effective date of the final rule be accepta ble, rather than having to conduct similar tests once again.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 24

Comment: The Preamble (pg 18673) states “EPA is proposing to limit the scoping test requirement to processes that would emit more th an one metric ton...”. The same paragraph does make it clear that engineering calculations can be used to estimate the mass of FGHG emitted from the process. This is in contrast to the “p reliminary estimate of emissions” prescribed in §98.123(b) that requires emissions to be determ ined from “each individual process vent”. The scoping test and emission factor te st should be on the same basis; i.e., by individual process vent

so that common data and calculations can be used more effectively for both regulatory sections. Estimating total emissions by process would requ ire estimating emissions from equipment leaks which would be imprecise prior to conducting the equipment leak testing as required in section §98.123(c). The scoping study should only be required for process vents, not equipment leaks.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

86Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 27

Comment: The preamble (pg 18673) states “EPA is proposing to lim it the scoping test requirement to processes that would emit more th an one metric ton...” The same paragraph does make it clear that engineering ca lculations can be used to esti mate the mass of fluorinated GHG emitted from the process. This is in contra st to the “preliminary estimate of emissions” prescribed in §98.123(b) that requires emissions to be determined from each individual process vent. The scoping test and emissi on factor test should be on the same basis, i.e., by individual process vent so that common data and calculati ons can be used more effectively for both regulatory sections. Estimating total emissions by process would require estimating emissions from equipment leaks which would be imprecise prior to conducting the e quipment leak testing as required in §98.123(c). Furthermore, EPA needs to clarify the time period for the one metric ton emission, as well as the fact that only fluorinated GHG emissi ons count towards the one ton

threshold.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 27

Comment: The proposed scoping test in §98.124(a) is overly complex and in many cases, unnecessary. Chemical facilities typically know what compounds ar e present in factory streams. There are other methods, besides this prescribed scoping test, that facilities can use to determine the compounds present in factory streams. Vent stream contents may be determined by a variety of methods, including historical information, measurements i nvolving processes with similar chemistries, and data obtained during bench scale and pilot plants. ACC member companies understand that they have an obligation to condu ct due diligence to adequately understand their emissions content, but this requirement should mo re generally state the facility will need to

document the methods that were used to make this determination.

Page 18674 of the preamble states th at “EPA is proposing to limit the scoping test requirement to processes that would emit more than one metric ton...” The same paragraph makes it clear that engineering calculations can be used to estima te the mass of fluorinated GHG emitted from the process. This is in contrast to the “prelimin ary estimate of emissions” prescribed in §98.123(b) that requires facilities to “estimate the annua l uncontrolled emissions of fluorinated GHG for each process vent within a process.” The scoping test and emission factor test should be on the same basis, i.e., by individual process vent so that common data and cal culations can be used

87more effectively for both regulator y sections. Estimating total emi ssions by process, as dictated by the scoping test, would require estimating em issions from equipment leaks which would be imprecise prior to conducting th e equipment leak testing as re quired in §98.123(c). Furthermore, EPA needs to clarify the time pe riod for calculating the one metric ton emission, as well as the fact that only fluorinated GHG emissions count towards the one ton threshold.

Section 98.124(a) requires the initial scoping test be performed by emission testing protocols in paragraph (c)(4)(v). Conducting the scoping stud y by stack test methods would be unnecessarily burdensome and costly. Some process vents with hazardous chemicals (HF, PFIB) are hazardous to test. When sampling these types of streams, the hazards can be multiplied because there might not be an existing sampling point. Also, some of the streams require a full acid suit and breathing apparatus for connecting and disc onnecting the sample cylinder. Th e sample systems that would be installed would most likely be 1⁄4” or 1⁄2” tubing manifolds th at would include connections for the sample cylinder itself but also ports for N 2, solvent washout, vacuum, etc. To make and

break these small connections whil e in an acid suit requires dext erity beyond that required for working with normal plant scale piping system s. For safety reasons, we recommend that emissions be measures post-destruction device, and, if necessary, EPA should allow upstream process testing by validated, industry accepted me thods to assess fluorin ated GHG byproducts.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 25

Comment: Scoping study stack testing, and engineering calculation options are unclear. Unsafe

to stack test considerations should be provided. EPA: Sect ion 98.124(a) requires the initial scoping test to be performed by emission testing protocols in paragraph (c)(4)(v). Page 18674 of the preamble states “For purposes of estimating the mass of fluorinated GHG emitted from the process, facilities could use the same types of e ngineering calculations th at they would use to determine whether process vent testing was required under the PSEF approach...” Section 98.124(c)(1) requires stack testing every 5 years to validate emission factors for vents that emit greater than 1Mtn/yr. Comment: Conducting the scoping study by stack test methods would be unnecessarily burdensome and costly. Some pro cess vents with hazardous chemicals (Hydrogen Fluoride, Perfluoroisobutene) are hazardous to test. When sampling these types of streams, the hazards can be multiplied because there might not be an existing sampling point. Also, some of the streams require a full acid suit and breathing air for connecting and di sconnecting the sample cylinder. The sample systems that would be in stalled would most likely be 1⁄4” or 1⁄2” tubing

manifolds that would include connections fo r the sample cylinder but also ports for N 2 , solvent washout, vacuum, etc. To make and break these sm all connections while in an acid suit requires dexterity beyond that required for working with normal plant scale piping systems. Some of our processes contain chemicals that are corrosive, to xic, or highly flammable with the potential to deflagrate if exposed to air during sampling. Increasing the personnel and environmental risks

88and costs for these additional sampling points are unnecessary for emission estimating purposes. EPA needs to allow up-stream process testing by validated, industry accepted methods to assess FGHG byproducts. Section 98.124(a) also needs to allow use of paragraph §98.124(c)(4)(vi)

which allows alternative methods.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 13, and comment number EPA-HQ-OAR-2009-0927-0104, excerpt 5.

Section 5.2 - Mass Balance Approach

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number : 8

Comment: The 1% calibration standard, instead of 0.20 percent, removes a substantial implementation barrier, but the Alliance is still concerned that it may be too tight given daily fluctuations in operations.

Response: We would like to clarify that the 1 pe rcent accuracy and precision requirement at §98.124(c)(3) (formerly §98.124(c)(5) in the April 2010 proposed rule) applie s to activity data used to develop emission factors and to estimate emissions under the emission factor approach. (Specifically, the provision require s such activity data to be meas ured using flow meters, weigh scales, or other measurement devices with an ac curacy and precision of ±1 percent of full scale or better.) These accuracy and precision requi rements are the same as those required for mass measurements under subpart OO, which were esta blished based on comments from fluorinated GHG producers.

As discussed in the preamble of the final rule and in the response to comment number EPA-HQOAR-2009-0927-0085.1, excerpt 49, EPA is establishing different precision and accuracy requirements for measurements under the mass-ba lance approach than for measurements under the emission factor approach. This is to ensu re that the emission es timates developed using either approach are comparably precise and a ccurate despite the mathematical differences between the approaches. The rule’s various a ccuracy and precision requirements are discussed further in the preamble to the rule and elsewher e in this Response to Comments document (see the responses to comment number EP A-HQ-OAR-2009-0927-0084.1, excerpt 4; comment number EPA-HQ-OAR-2009-0927-0104, excerpt 3; and comment number EPA-HQ-OAR2009-0927-0128.1, excerpt 15).

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 28

89Comment: Section 98.124(b)(2) requires that “The following concen tration measurements shall be measured on a regular basis using equipment and methods (e.g., gas chromatography) with an accuracy and precision that allow the facility to meet the error criteria in §98.123(a):...” It is unclear how “regular basis” is de fined. We believe that EPA shoul d clarify that “regular basis” is every five years, or more frequently, as appropriate and documented in the facility’s GHG Monitoring Plan.

Response: In the final rule, we have clarified thatthe concentration measurement frequency for the mass balance approach is at least one time pe r month. As discussed in the preamble of the April 12, 2010 proposed rule (75 FR 18675), this was what we intended, rather than the generic “regular basis” text. Note th at under the final rule, facilities using the mass-balance approach may be required to measure concentrations more frequently under some circumstances. For more discussion of sampling frequency under the mass-balance appr oach, please see the preamble of the final rule and the respons es to comment numb er EPA-HQ-OAR-2009-0927- 0128.1, excerpt 15 and comment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 26.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 29

Comment: “On a regular basis” for analysis of ve nt streams should be a 5 year frequency. EPA: Section 98.124(b)(2) states: “The follo wing concentration measurements shall be measured on a regular basis using equipment and methods ...” Comment: The testing frequency should be consistent with Subpart L, and typi cal Title V stack testing frequencies unless a significant process change occurs.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 28.

Section 5.3 - Process Vent Emissions Factor Testing

Section 5.3.1 - Operating scenarios

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 26

Comment: §98.124 (c)(2), Different Op erating Conditions. Vent gas measurements are an important element in the development of emission factors for certain types of sources. However we believe that this method can also [be] comb ined with other methods to define emissions under slightly different operating conditi ons. We offer the following examples:

901. Two different systems may operate at different rates, but the fi nal product will be the same and the mass emission factors, i.e., kg F- GHG emitting/kg product, will also be the same. 2. Two pieces of equipment produce the same product. For one process, during system stabilization, a small amount of product will be vented to the pollution control device as an operational control. This does not occur in the other process. In this case, we would adjust the emission factors to account for the produc t loss using engineering calculations.

Response: EPA agrees that for closely related oper ating scenarios, it is appropriate to allow

facilities to use calculations to ad just the emission factor measured for one operating scenario to develop an emission factor for the other operating scenario.

To assess whether a continuous process vent emits 10,000 mtCO 2 e or more (and therefore must be tested), facilities are requi red to sum the process vent’s em issions across all of the operating scenarios for the process for the year. If emissions from the vent equal or exceed 10,000

mtCO 2 e, facilities are required to identify the opera ting scenario with the largest emissions and conduct emissions testing on that operating scenario. Emissions testing of other operating scenarios is only required if (1) emissions under the other scenario equal or exceed 10,000

mtCO 2 e, and (2) the emission calculation factor for the other scenario differs from the emission

calculation factor of the scenario with the largest emissions by 15% or more (and this difference is not due solely to the applica tion of a destruction device under one of the operating scenarios). Under these circumstances, applying an adju sted emission factor to the second operating

scenario would result in an emi ssions estimate with significant un certainty, due to the significant differences between the emission rates (i.e., emi ssion calculation factors) of the two operating

scenarios and the size of the em issions from the second. However, for other operating scenarios that do not meet these criteria, the facility may develop an adjusted emission factor by multiplying the emission factor measured for th e first scenario by the ratio of the emission

calculation factor for the other scenario and the em ission calculation factor for the first scenario.

It is anticipated that adjusting emission factors for multiple operating scenarios will rarely be a significant issue in the fluorinated gas producti on source category. Processes with multiple operating scenarios are most likely to be batch processes, and batc h processes in the final rule may develop emission calculation factors for proce ss vents (i.e., they are not required to conduct emission testing). Continuous processes are less likely to have multiple operating scenarios, although some facilities have indicated that there could be cases wh ere this exists (one facility mentioned as an example the use of “flexible operating units”, under th e HON, where more than one product is made in equipment). Consider an example where a faci lity has two identical production lines or perhaps two sim ilar production lines that make th e same product. In the case with two identical production lines making the sa me product, the two production lines would be part of one process, and both lines together w ould represent one operating scenario (because the equipment is identical), if each line were vented to the same control device. The emission factor developed from emission testing on the first line could be applied to the second line, without additional testing or emission ca lculations required. In a ca se where a facility had two production lines that were similar, but one was la rger volume than the other, for example, the two production lines would be part of one proce ss, but each line would be a separate operating scenario. To determine whether testing would be conducted, a facility would sum the emissions

91for each process vent over all operating scenarios emi ssions that are sent to that process vent. If the combined emissions for a process vent (summe d for the two operating scenarios that are sent through the vent) are greater than or equal to 10,000 mtCO 2 e, then the larger operating scenario with the most significant annua l emissions would be tested. Depending on the size of the second operating scenario, an emission calculation could be conducted for the second operating scenario or additional testing may be done. If the emissions of the second lin e (operating scenario) through the process vent, in themselves, exceeded 10,000 mtCO 2 e, the facility would develop emission calculation factors for both the first and the second operating scenarios. The facility would then compare the two emission calculation factors. If the difference was more than 15 percent, the facility would conduct emission testing on the second operating scen ario. If the difference was less than 15 percent, the facility would adjust the emission factor developed for the first operating scenario.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 44

Comment: Proposed §98.127(b)(7) requires reporters to identify “whether the process was representative or whether it was another operating scenario.” We believe that EPA is requesting reporters to document operating scenario change s over time and times where operations were not representative of the §98.124 basis. EPA should clarify this language, and include provisions documenting new operating scenarios and process changes that do not constitute new operating

scenarios.

Response: EPA has removed the operating scen ario paragraph from §98.127, Reporting requirements, and has clarified when differen ces between and changes to operating scenarios trigger new calculations or testi ng. Differences between operating scenarios are discussed in the response to comment number EPA-HQ-OA R-2009-0927-0111.1, excerpt 26. For more discussion of this issue, please see the response to comment nu mber EPA-HQ-OAR-2009-0927- 0085.1, excerpt 47.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 52

Comment: EPA should further clarify that the §98.124( h) control device deviation requirements do not apply for alternate operating scenarios re flecting Clean Air Act permit or applicable requirement authorized activities.

Response: The term “deviation” has been removed from the final rule text. The rule text now explains that, rather than repor ting periods of deviations of th e destruction device, facilities should report any emissions that occur duri ng these deviation peri ods, if applicable.

92With respect to defining different operating scenarios, th is could certain ly be done. For example, a facility could define one operating scenario fo r the process that incl uded venting fluorinated

GHG emissions to the destruction device. Because the destruction device could malfunction, the facility could also define another operating scenario that incl uded venting of fluorinated GHG

emissions to another control devi ce, or simply uncontrolled venting or bypass. In general, as long as a facility tracks the pro cess activity associated with each defined operating scenario and accounts for the emissions during the year for each situation, defining different operating scenarios is acceptable.

For further discussion of this issue, please see the response to co mment number EPA-HQ-OAR2009-0927-0085.1, excerpt 50.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 41

Comment: EPA should clarify certain details co ncerning the proposed §98.124(f)(5) process change requirements. First, EPA should clarif y that the §98.123(b)(1) pr eliminary assessment is an appropriate process to conduc t the process ch ange analysis.

Response: We have deleted paragraph §98.124(f)(5) from the final rule text, and use of the term “process change” has been taken out of the final ru le. We have clarified in the final rule that modifications or changes to operating scenarios would require a check on the emission factor. We agree that the emission calculations conducte d for the preliminary assessment of emissions are appropriate to evaluate changes in the magn itude of emissions from modifications. Please see the response to comment number EPA-HQ-OAR-2009-0927-0085.1, ex cerpt 44 for more

discussion of this issue.

Section 5.3.2 - Identify Emission Epis odes (e.g., using emissions profiles)

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 24

Comment: EPA proposed to require testing of process vents emitting more than 10,000-mtpy

CO 2 e FGHG not routed to a cont rol device reducing emissions by at least 99.9%. However, EPA did not clarify in the proposed 40 CFR 98.124(c) that recognized batc h emissions evaluation

methods could be used. Pharmaceutical MACT al lows batch process operators to develop an “emissions profile” per 40 CFR 63. 1257(b)(8)(ii)(A) that allows the operator to document the magnitude of emissions across a batch manufact uring process. 40 CFR 63.1257(b)(8)(i)(A) then allows the operator to choose among three batch testing situations, each of which demonstrates

93emissions (and control device perf ormance, if appropria te) under appropriat e testing conditions. For Part 98 testing, the reporter c ould prepare the emissions profile on a GWP basis in lieu of the RSD basis in proposed 40 CFR 98.124(c)(3). This proposal would also optimize testing time, especially when a reporter can demonstrate in th e profile that a peak em issions event occurred during multiple batch episodes.

To meet the three one-hour runs required at §98.124(b)(3), the reporte r should be required to test during the peak emissions event for three successive batches, where the peak event time must be contained with the test run time. If the peak ev ent occurs over less than one hour, the test run would continue for one hour. If the peak event o ccurs over more than one hour, the test may need to be extended long enough to encompass the appropriate peak, as provided for in 40 CFR 63.1257(b)(8). If the outlet concen tration during the peak emissi on event is below the method detection limit, as described above, the test woul d show compliance for the entire batch cycle.

Response: As discussed in the preamble, we are allowing facilities to use emission calculation factors for all batch processes regardless of size due to several technical issues that make it difficult to develop accurate emission factors fo r batch process vents ba sed on emission testing.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 27

Comment: We are concerned about the require ments for characterizing batch process emissions. There are many technical problems asso ciated with the characterization of batch emission episodes using traditional stack testing methodologies. Our great concern about testing of batch processes is not when to perform the test (i.e., when the process vent is open) or the test protocol (stack test protocol opt ions are well established), but rath er how to get a representative sample and representative flow rate. To get a representative emission ra te using stack sampling, the vent rate and composition need to be relatively constant and/ or predictable over the sampling period. This cannot be accomplished with many of our batch operations. However, there are EPA approved methods for calculating these emission s. We are already using these methods to calculate our air emissions for Title V purposes. We propose that if these emissions need to be determined, using the calculation methods should be the approved approach to estimate the emissions. The Miscellaneous Organic NESHAP recognizes these issues and only requires engineering calculations to characterize these em issions, especially from these processes. The Miscellaneous Organic NESHAP cal culation protocol focuses testing on those batch steps that emit the most materials, or those steps that co mprise most of the batch emissions. ACC urges EPA to allow reporters to profile batch emissi ons and use the profiles to guide testing. EPA should further extend this concep t to provide that, below certain significance thresholds, testing is not required. We believe that the significan ce thresholds used in subpart OO reporting, in

terms of CO 2 -equivalent mass per year or mass per year of compounds not identified on Part 98 Table 1, are appropriate to focus testi ng efforts on significan t emission points.

94Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-085.1, excerpt 24.

Section 5.3.3 - Continuous Process Vent Emissions Factor Testing

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 27

Comment: §98.124 (c)(3), Number of R uns Continuous Process Vents. 3M has previously discussed its concerns regardi ng the ability to specifically id entify all compone nts that are contained in every gas stream. 3M would have similar concerns with the requirements in this section. For continuous process vents, we are re questing that the testing be limited to three one hour runs as this is consistent with testing specif ications that are listed in other rules. If the 0.2 RSD requirement is applied to each fluorinated -GHG that is contained in a vent stream, we believe that six (6) runs would likely be required for every emissi on factor. When viewed as the

total mass of fluorinated-GHG or the total of sum of CO 2 e contained in the gas stream, we believe that the 0.2 RSD would be more easily achie vable. Typically 3M has conducted this type of testing using FTIR analytical instrumentation which provides continuous results of process vent composition. In these cases, we will be ab le to determine an RSD during the stack gas sampling campaign. We are most concerned about th e application of the accu racy requirement to constituents that would be present at smaller concentrations and the ability to meet this requirement for every constituent.

Response: In the final rule, we are retaining a requirement to evaluate the relative standard

deviation of the three test run emission factors in order to determine whether more than three test runs are necessary. However, for purposes of ca lculating the relative st andard deviation (RSD) of sample emission factors, we are allowing f acilities to apply a default GWP of 2000 to

fluorinated GHGs that do not have GWPs listed in Table A-1 to subpart A. In general, we anticipate that this will make it easier for faci lities to meet the RSD requirement and avoid additional testing.

As noted in the March 2010 Technical Support Document, a minimum of three emission test runs is appropriate to determine the variabil ity of the emission rate for a given operating

scenario. In cases where there is little variab ility among these three runs , and therefore the RSD is low, the average of these values is likely appr opriate for use in determining the emission factor for the process. However, if these three runs show significant variability, such that the RSD is high, then this average is likely a poor representation of the actual mean emission rate from the process, and additional samples must be taken in order to develop a r obust emission factor.

In the final rule, we have decreased the RSD leve l that triggers additiona l testing from 20 percent to 15 percent. This change wa s necessary to ensure a reasonable level of consistency between the precision requirements for process vent em ission factor measurem ents and the precision requirements for measurements elsewhere in su bpart L and in other EPA methods. As we

95proposed, we are setting a rela tive error limit of 30 percent 1 for estimates developed using the mass-balance approach. The uncertainty (based on a 95-percent confidence level) of an emission

factor that is based on three em ission measurements with an RSD of 20 percent is 50 percent, 2
which is considerably higher th an the 30-percent limit set for the mass-balance approach. To provide 95-percent confidence that the measured emission factor fell within 30 percent of the true mean emission rate for the process after ju st three samples, the maximum RSD would be 12 percent. However, as noted in the Technical Support Document, th is could be a difficult RSD to meet even when the real emission rate was nearly constant because the error of the concentration measurements used in the testing can be near 10 percent. An RSD of 15 percent, in contrast, is likely to be broadly achievable, and does provi de 95-percent confidence that the measured emission factor falls within 40 percen t of the true mean emission rate. 3 Moreover, an RSD of 15 percent is used to trigger a dditional testing in at least one other EPA method. Specifically, EPA’s method for validating test methods, Me thod 301 (Field Validation of Pollutant Measurement Methods from Various Waste Media) , requires three replicate samples for followup testing if the RSD of the sample s is 15 percent or lower, but re quires six replicate samples if the RSD of the samples falls between 15 and 30 percent.

While the decrease in the RSD level that triggers additional testing would, by itself, increase the stringency of the final rule compared to th e April 2010 re-proposal, ot her changes between the re-proposed and final rule are lik ely to counteract this increase. First, as noted above, we are permitting facilities to calculate their RSDs in CO 2 -equivalent terms across the emitted fluorinated GHGs, using a default GWP of 2000 fo r fluorinated GHGs that do not have GWPs in Table A-1. In the proposed rule, facilities would have had to cal culate a separate RSD for any

fluorinated GHG that did not have a GWP in Ta ble A-1. As observed by many commenters, it is easier to achieve an RSD below a given level across gases than it is to achieve this for any particular gas, particularly if the gas makes up a relatively small fraction of the total emitted mass. Second, we are adopting numerous changes to the rule to increase its flexibility, including allowing use of engineering calculations and a ssessments to estimate emissions for all batch process vents, regardless of emission level, and changing the manner in which emissions from continuous process vents are calcul ated for comparison to the 10,000 mtCO 2 e threshold. These changes are discussed in more detail in the pr eamble and in the res ponse to comment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Moreover, the uncertainty estimate d by one facility for its emissions estimates using the emission factor approach (about 25 percent), which accounte d for process variability, implies that the RSD of the three runs will rarely exceed fifteen percent. 4

In summary, we expect that despite the change to the RSD, the final rule will rarely, if ever, require facilities to perform add itional testing that they would not have been required to perform under the proposal. However, where such additiona l testing may be require d, it will be justified

1 The mass-balance error limits also include an absolute error limit, but that is not relevant to the large processes that would be required to perform stack testing under the emission factor approach.

2 Technical Support Document for Emissions from Production of Fluorinated Gases, Proposed Rule for Mandatory Reporting of Greenhouse Gases. U.S. Environmental Protection Agency, March 22, 2010.

3 For emissions that showed an RSD of 20 percent after three measuremen ts, the requirement that three more measurements be taken would reduce the uncertainty of the emission factor from 50 percent to 21 percent.

4 Alternatively, the facility may have pe rformed additional testing when it did.

96by the significant improvement in the accuracy and precision of the resulting emission estimate for the process vent.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 15

Comment: §98.124 (c)(1), Process Vent Testing. The section requires testing at five year intervals. 3M requests that EPA eliminate any specific testing frequency. As a practical matter and for a variety of reasons, 3M measures many of its major continuous processes at this frequency, but we feel it would be more appropriat e to either extend this frequency to 10 years or only when major process changes occur. In EPA’ s request for comments, they have suggested that a possible alternative woul d be to require measurement only when emissions deviated by 15% (as a fraction of the current emission). 3M supports this approach with the following

recommendations:

1. Measurement is not required when emission changes can be reasonably predicted using engineering calculations and/or other process information. The re quirement to retest processes would appear to be particularly punitive when the resulting change has decreased emissions.

2. An additional consideration would be the use of a thermal treatment device to treat process emissions. In the case of controlled sources, proc ess changes would likely have little impact on the ultimate emissions from the process. We wo uld suggest exempting process changes that fall into this category. 3. Retesting only when monitoring of process yields indicates a st atistically significant decrease in process yield unless this yi eld loss is associated with known losses of liquid and solid byproducts.

Response: In response to this and other comments noting that process ve nt testing should be repeated every ten years or when significant changes are made to the process, we are requiring that process vent testing be repe ated every ten years or when a ch ange (or series of changes) to the operating scenario changes the emission cal culation factor by 15 percent or more. The requirement to retest when the emission calcula tion factor changes by 15 percent or more will ensure that the emission factor will promptly reflect significant, deli berate changes to the operating scenario. The 10-year testing cycle will address suc cessive small changes to the process that may not individually constitute delib erate changes to the operating scenario (and may not, in fact, have been noticed), but that may nevertheless cumulatively affect the emission

factor.

In the April 2010 re-proposed rule, we proposed to require retesting every five years. However, we requested comment on the options of extending the five-year retest pe riod to ten years and triggering new emission factor measurements when changes to other process parameters, such as process yields, implied that the emission f actor had changed by 15 percent or more . Commenters generally suppor ted these options.

97When changes to the operating scenario change the emission calculation factor by 15 percent or more, we believe that retesting, rather than recalculation or ad justment, of emission factors is appropriate. A 15-percent change in the emission calculation fact or implies that the change to the operating scenario is signifi cant. Significant changes to (o r differences between) operating scenarios can lead to changes to both the magnitudes (i.e., CO 2 e) and mixtures (i.e., proportions of different fluorinated GHGs) of emissions, a nd not all of these cha nges are likely to be predictable from emission calculations. (One change that is predicta ble is a change that is due to the application of a destruction device to the em issions; in this case, th e rule does not require retesting.) This concern exists regardless of whether emissions ar e expected to be decreased or increased by the change; the goal of this regulati on is a reasonably accurate emissions estimate in

either situation.

Regarding retesting of emissions streams that ar e destroyed, the rule now requires facilities to evaluate controlled emissions, rather than uncontrolled emissions, to make the initial

determination of whether emissions fr om the process vent exceed 10,000 mtCO 2 e and therefore must be tested in the first place. If controlled emissions exceed 10,000 mtCO 2 e, then a 15- percent change to these emissions is signifi cant and warrants retes ting regardless of the

destruction device.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 47

Comment: The emission factor testing fre quency provisions at proposed §98.124(c)(1) represent a substantial improve ment from the 2009 proposal. A five-year testing frequency (absent process changes) is appropriate fo r the first five-year period after Subpart L implementation. However, after obtaining sign ificant experience with tracking and recording actual FGHG emissions, reporting facilities wi ll likely develop adequate systems to fully document and verify FGHG emissions and DRE w ithout conducting full testing protocols every five years. Reporters are alrea dy required to verify emissions calculations every five years at proposed §98.124(d)(1). EPA should provide a “skip schedule” for testing of processes that do not change over time. For consistently operated processes, every ten years is appropriate for performing this test protocol, once the reporter has established the appropriate baseline. EPA should allow reporters to certify every other testing cycle that th e prior five-year source test adequately represents current FGHG emissions and DRE performance. Under this proposal, a reporter would not be required to test except for once every ten year s, so long as the facility did not meet the process change criteria at any poi nt in the prior ten year s. EPA should provide a mechanism for reporters to verify process performa nce for a five-year period in lieu of testing if no process changes have occurred in a specific reporting process unit.

Response: We agree with the commenter that a 10-year frequency for conducting emission testing for emission factor development is appr opriate and have revised the testing frequency requirement in the final rule. In addition, we have clarified the circumstances under which a change (or series of changes) to an operating sc enario triggers additiona l testing or calculation.

98Under §98.124(c), the final rule requ ires that if the emission calcu lation factor for the changed operating scenario is 15 percent or more different from the emission calculation factor for the tested operating scenario, then the facility must retest to update the emission factor. The 15 percent difference is cumulative since the last emission factor develope d by emission testing. Under §98.124(d), facilities must update the emissi on calculation factor if a change to the operating scenario is expected to change the process-vent-specifi c emission calculation factor.

Please see the response to comment nu mber EPA-HQ-OAR-2009-0927-0111.1, excerpt 15 for

more discussion of this issue.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 48

Comment: EPA should further clarify that the §98.124(d)(1) FGHG emissions verification process does not necessarily require a full recons truction of the reporting basis. The introductory language §98.124(d)(1) implies that reporters are required to “[r]evise the emission calculation for each process every 5 years.” Revision is not necessary for pro cess units not undergoing process changes. Likewise, if a reporter can document that the em issions basis of an alternate operating scenario is identical to an existi ng operating scenario, th e §98.124(d)(2) separate operating condition emission factor requirement may not be nece ssary. EPA should clarify that separate emission factors are only necessary when the value of the emi ssion factor is either significantly less than, or is greater than, the base emission factor.

The “representative performance” testing criteria properly reflects actual emissions testing. This criterion allows reporters to document the subs tantial emissions sources without the need to

document the rare maintenance activities that do not significantly contribute to actual FGHG

emissions.

Response: We agree with the commenter that fre quent updates are not necessary for process units not undergoing process or operating scenario changes or modifications. In the final rule, we are requiring that emission calculation factors be updated wh en operating scenario changes are expected to affect them. Otherwise, th ere is no requirement to recalculate emission calculation factors (i.e., there is no separate minimum frequency of recalculation). Because facilities are already required to recalculate f actors when they make deliberate changes to the operating scenario that will aff ect the factors, and because fa cilities cannot, by definition, recalculate factors to reflect changes of whic h they are not aware, a minimum frequency of recalculation is not likely to impr ove emission calculation factors.

Regarding the calculation of different emissi on calculation factors fo r different operating scenarios, as discussed in the respon se to comment EPA-HQ-OAR-2009-0927-0111.1, excerpt 26, different sets of equipment that make the same product, if they are identical, may be considered the same operating scenario. In this situation, an emi ssion calculation factor developed for one production line may be applie d to the other. In situations where the

99equipment or other aspects of the operating scenar ios differ slightly, the fa cility would need to perform engineering calculations or assessments to demonstrate the similarity between the scenarios before applying the emission calculation factor developed for the first to the second. At this point, the facility would have done the work to develop a second emission calculation factor. Thus, it is not clear wh at the facility would gain by ap plying the factor for the first operating scenario to the second.

EPA agrees that the emission factor should be ba sed on representative operation of the process. In general, the emission factor should not includ e startup or shutdown events unless the emission testing occurs over a long enough period that including th ese events would not inadvertently bias

the emission factor resu lt. We would like to note however that in §98.124 (j), the rule requires

that facilities account for start up, shutdown, and malfunction events for the process in the annual emission estimate, or else confirm that these events do not significantly affect the annual emission estimate. For example, if a periodic dist urbance occurs in the process, and this occurs on a fairly frequent basis, the emissions from each event could be estimated and summed in the annual emission estimate. The emissions for each event could be determined separately, or in some instances, something along the lines of an emission calculation factor for the disturbance

event could be determined. It is likely that process malfuncti on events will be random and the magnitude of emissions will vary, although industr y has noted that emissions from startup, and perhaps shutdown events too, are fairly c onsistent from one event to another.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 39

Comment: EPA should further clarify the re lationship between §98.126(f)(6) testing requirements and reporter’s use of updated emi ssion factors. Reporters may update emission factors based on process design documents quickly, even before the process change takes place. These pre-startup calculations may even show th at no EPA process change will take place for a specific project. The lag time betw een startup and testing, including production of the test report, could take several months. EPA should encourage reporters to utilize up dated emission factors upon startup of process changes, require reporters to utilize §98.123 met hodology to determine if a process change occurs before the reporter im plements any significant process modifications, and should allow reporters 90 days after submitting a test report to either validate or update emission factors. Reporters making process cha nges that do not increase actual FGHG emissions, using traditional CAA definitions, should not be re quired to retest or restate emission factors. EPA’s 15% suggestion at 75 Fed. Reg. 18678/3 appr opriately balances the need to adjust emission factors and the need to not expend larg e costs to document trivial FGHG emission rate changes. These emission factor streamlining steps better allow reporters to adjust their reporting systems for process changes, while allowing use of best engineering practices to evaluate when further testing is required.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 15. We have clarified in the final rule that, for emission f actor updates that are made due

100to an operating scenario change, the emission tes ting required to update the emission factor must be conducted by February 28 of the year following the change or modification. We have also clarified that the updated emission factor must be applied to the process ac tivity that o ccurs after the operating scenario change. Together, we be lieve that these provisions will allow sufficient time to conduct the testing while en suring that the change to the emission factor is promptly and appropriately reflected in the f acility’s emissions estimate. For emission factor updates that are made due to the passage of ten years since the previous measurement, the updated emission factor must be applied to the process activity that occurs after the most re cent measurement.

Note that EPA has not included requirements to submit actual emissions test reports to the Agency under this subpart. However, EPA is requiri ng that facilities retain records of emissions test reports (including revised re ports). The emissions test repor t must contain all information and data used to derive the process-vent-spe cific emission factor, as well as key process conditions during the test.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number : 20

Comment: In [section] B. Fluorinated Gas Production, Section 5.d. [of the re-proposal preamble], EPA requests comment on whether pr eviously measured emission factors whose measurement departed in some particulars from th e requirements of the rule but still substantially met most of the requirements, making it likely that the emission factors were representative, could be used if the facilities provided info rmation to EPA on the areas where measurements departed from the requirements of the rule for EPA review and ve rification. Air Products supports this alternative approach to prescriptive test methods and the additional costs associated with conducting unnecessary tests.

Response: EPA appreciates your comme nt regarding use of previ ous emissions testing that meets the requirements of the rule. We are allowi ng facilities to use previous measurements to develop emission factors as long as those meas urements meet the testing requirements in §98.124(c) and the method requirements in §98.124(e) , and as long as the measurements were made less than ten years before the effective date of the rule. We have determined that these requirements allow a reasonable degree of flexibil ity while ensuring that the resulting emission factors are precise and accurate. As discusse d in the preamble, we have included additional flexibility at §98.124(e) to select appropriate , validated sampling and analytical methods (including validated, industry-accepted methods). As discussed in the preamble and elsewhere in this response to comments document, we ha ve designed the emission test requirements to

result in accurate and robust emission factors. (See, for example, the response to comment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 27.) The requirement that the measurements be no more than 10 years old is consistent with the measurement frequency established for emission factors elsewhere in subp art L; the final rule requires that emissions factors be redeveloped every 10 years. For use of previous emissions tests in general, the date on which the previous emission testing was conducted begins the 10-year re-measurement cycle.

101Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 34

Comment: Consolidated Control Devices. EP A requires reporters operating manifolded

FGHG control devices to run three one-hour test runs for each contributing process at proposed §98.124(c)(6), rather than three one -hour runs for the composite flow into the control device. Arkema routes multiple emissions units into Calver t City facility emission controls systems. We expect that this proposal al one would cost the Calvert Ci ty facility between $150,000 and $200,000 per testing cycle, assuming proposed testing requirements. Reporters must, in the scoping test process, document the expected emi ssions contributions from each reporting process unit. Reporters can use this analysis to al locate FGHG emissions among contributing processes

to a control device and avoid th e expense of separate testing. EPA should provide a testing

alternate that allows faci lities to evaluate total te sted FGHG load to a control device, determine if the scoping test analyses predict total contro l device loading to with in 20% of the observed tested amount, and determine if further testing of individual contributing process units is needed to document the control device FGHG loading. Allo wing reporters to utilize the scoping test to optimize testing would likely save Ar kema over $100,000 per testing cycle.

Response : EPA has revised the requirements for sa mpling of manifolded process vents to a destruction device. The requireme nt to conduct 3 test runs for each process vent sent (i.e., the “3n” test runs) to the destruction device has been deleted from the final rule text. We would like to note, however, that for sampling with multiple process vents manifolded together, facilities would be required to meet the RSD of 0.15, so poten tially up to 6 test runs may be required.

An additional alternative with respect to sampli ng of manifolded process vents has been included in the final rule. As in the April 2010 proposed rule, facilities may sample the process vent before the manifold or while a single process is operating. The alternativ e approach included in the final rule allows a facility to operate multip le processes and sample the manifolded process vents. The facility may conduct emission calcul ations for each of the individual process vents using the same methods used to estimate emi ssion calculation factors in §98.123(c)(4). The sum of these emission calculations by process vent a nd process must be compared with the emissions determined during testing. If the sum of the emissions determined by calculation is within 20 percent of the emission testing value, the facil ity may apportion the emissions to each process vent and develop an emission factor for each process vent on this basis.

Section 5.3.4 - Accuracy and Precision for Process Activity

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 49

102Comment: Reporters document a variety of proce ss activity variables fo r a number of existing Clean Air Act obligations. EPA should clarify at proposed §98.124(c)(5) that parameters already used for other Clean Air Act compliance obligat ions will be managed in the manner required by the underlying permit or regulatory condition. A ll post-1990 EPA emission standards at 40 CFR 60, 63, and 64 require adequate data accuracy prot ocols to document monitoring integrity. EPA should rely on existing Clean Air Act authoritie s when possible to avoid redundant, overlapping, or conflicting instrument and/or data management obligations.

Response : While EPA appreciates the commenter’s suggestion to rely on existing CAA obligations, we are establishing precision, accuracy, and calibration requirements in this final rule to ensure that emission estimates develope d under this rule are reasonably accurate and precise. Specific accuracy, precision, and calib ration requirements may vary among regulatory programs depending on how the measurements are used. Please see response 1-b in the Response to Comments Document for Cross-Cu tting Comments for more discussion of this issue. For an additional example, even within subpart L, we are establ ishing different accuracy and precision requirements for measurements thatare used to develop estimates using the massbalance approach and for measurements that ar e used to develop estimates under the emission factor approach. These differences are driven by the mathematical differences between the two approaches. Because the mass-balance approach estimates emissions based on a small difference between large quantities (i.e., the masses of reactants and products ), highly precise and accurate measurements of those quantities are required to yield an estimate of emissions whose accuracy and precision are comparable to those of an estimate developed using the emission factor approach based on less precise measurements. The rule’s various accuracy and precision requirements are discussed further in the preamble to the rule and elsewhere in this Response to Comments document (see e.g., the respons es to comment number EPA-HQ-OAR-2009-0927- 0084.1, excerpt 4; comment number EPA-HQ- OAR-2009-0927-0104, excerpt 3; and comment number EPA-HQ-OAR-2009- 0927-0128.1, excerpt 15).

Section 98.124(c)(3) [formerly §98.124(c)(5) in the April 2010 proposed rule] requires that activity data used to develop emission factor s and to estimate emissions under the emission factor approach be measured using flow mete rs, weigh scales, or other measurement devices with an accuracy and precision of ±1 percent of full scale or better. These accuracy and precision requirements are the same as those re quired for mass measurements under subpart OO,

which were established based on comments from fluorinated GHG prod ucers. If facilities have monitoring instruments in place that meet the 1 percent requirement, these instruments may

continue to be used. Under §98.124(m), facilities are required to initially and periodically calibrate their mass measurement devices using cons ensus standards listed in subpart L or other calibration procedures recommended by the manufact urer. Recalibrations are required to occur at the frequency recommended by the device manuf acturer. We anticipate that the revised provisions that allow use of consensus met hods and manufacturer-r ecommended methods and frequency will provide adequate flexibility for faci lities to coordinate the requirements of this rule with those of other regulatory programs.

103Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 26

Comment: We support EPA’s proposal allowing fo r monthly sampling. We also support EPA’s proposal in §98.124(d)(3) to allow for an accuracy and precision of ±1 percent for process activity measurements.

Response : EPA appreciates your comment and support. We would like to note that the monthly sampling the commenter refers to is for the mass balance approach. For the mass balance approach, the monthly sampling requirement is a minimum; facilities may need to sample processes with variable concentra tions more frequently to ensure that they meet the relative and absolute error criteria. (In the variant of the mass-balance approach that establishes specific precisions, accuracies, and frequencies for meas uring mass flows and concentrations, sampling must be conducted weekly.)

The accuracy and precision requirements in §98. 124(d) to which the commenter refers are related to the activity data used to develop emi ssion calculation factors and to estimate emissions using emission calculation factors. Similar accuracy and precision requirements at §98.124(c) apply to the development and use of emission factors. We have concluded that these requirements will result in emission estimates of reasonable accuracy and precision using the

emission factor and emission calculation factor approaches. However, as discussed in the response to comment number EPA-HQ-OAR-2009-0927-0104, excerpt 3, we have concluded that, under the mass-balance approach, an accuracy and precision of this le vel would result in emission estimates with high relative errors.

For more discussion of sampling frequency unde r the mass-balance appr oach, please see the preamble of the final rule and the resp onse to comment number EPA-HQ-OAR-2009-0927- 0128.1, excerpt 15.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 23

Comment: Section 98.124(d)(3) states: Use flow meters, weigh scales, or other measurement devices or instruments with an accuracy and prec ision of plus or minus 1 percent full scale or better for monitoring ongoing process activity.” Section 98.124(b) states: “If you determine fluorinated GHG emissions using the mass bala nce method under §98.123(a), you must estimate

the total mass of each fluorinated GHG emitted fro m the process at leas t monthly. DuPont supports monthly sampling and 1% accurate measurement devices.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 26.

104Section 5.4 - Allow Alternative Sampling and An alytical Methods (MB and process vents)

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 30

Comment: Section 98.124 (b)(4)(v) and (vi) lists specific test methods and the preamble language has indicated that constituents present at concentrations of 0.1% or greater must be quantified. 3M has met this performance requirem ent on some of its major vent emissions. Using FTIR (EPA Method 320) and GC/MS (TO-15), we ha ve been able to identify and quantify (with standards) as much as 99.7% of certain vent gas streams. We have had th e capability to identify compounds that comprised as little as 0.002% of the total vent stream.

However, there are process vent streams in whic h characterization at th e 0.1% level will not be possible. Due to reactions occurring in some batc hes processes, there is greater complexity in these vent gas streams. There is greater po tential for the presence of unknown compounds for

which certifiable standards do not exist. The listed test methods require the use of certifiable standards. Therefore additional analytical methods and procedures, such as the use of surrogate calibration compounds, are required to address this issue. We are recommending that the language that was developed as a part of the S ubpart OO discussion be incorporated into this section. It is provided below:

“Analytical Methods. Use a qua lity-assured analytical meas urement technology capable of detecting the analyze of interest at the concentration of in terest and use a procedure validated with the analyze of interest at the concentrati on of interest. Where standards for the analyze are not available, a chemically similar surrogate may be used. Acceptable analytical measurement technologies include but are not limited to gas chromatography (GC) with an appropriate detector, infrared (IR), fourie r transform infrared (FTIR), and nuclear magnetic resonance (NMR). Acceptable methods include EPA Met hod 18 in Appendix A-I of 40 CFR part 60, EPA Method 320 in Appendix A of 40 CFR part 63, the Draft EPA DRE Protocol, ASTM D6348-03 (incorporated by reference in §98. 7), or other analytical met hods validated using EPA Method 301 or some other scientifically sound validation protocol. The validation protocol may include analytical technology manufacturer sp ecifications or recommendations.”

3M does not believe that this will have a sign ificant impact on our emission estimates. We have the capability of positively identifying and quantifying a high percentage of our emissions. When unknowns have been present, their GWP values ha ve been estimated using the weighted average of the known compounds that are present. We ha ve verified these assu mptions with process knowledge, historical information, and other an alytical information. In most cases, unknown compounds will have structural similarities with t hose that have been positively identified, and we expect GHG’s to be comparable.

In addition to the language provided above, EPA should include both EPA Method TO-15 and EPA TO-14a. Both methods allow for samples to be collected in canisters. In many fluorochemical manufacturing processes, canisters are easier and safer than tedlar bags. EPA

105method TO-14a also allows for the use of multip le detectors which will be helpful for these

matrices.

Response: The commenter requests that EPA allow facilities to use sampling and analysis methods other than EPA’s emission testing referen ce methods. As discussed in the preamble of the final rule, EPA agrees that a dditional flexibility is appropriate and is allowing facilities to use alternative test methods and procedures to iden tify and quantify fluorinated GHGs in process and emissions streams. The sampling and analytical requirements that we are incorporating into subpart L are very similar to those that w ould be required under §98.414(n) in the proposed amendments to subpart OO (75 FR 48744; Augus t 11, 2010). The revised requirements allow

facilities to conduct validated sa mpling and analysis methods using appropriate analytes or surrogates. These alternative methods and proce dures must be validated and documented in the facility’s GHG Monitoring Plan. EPA has concluded that this change will provide the flexibility necessary to allow facilities to develop and appl y new analytical procedures that may be required to identify and quantify a ll of the fluorinated GHGs in process and emissions streams. At the same time, the quality assurance, validation, and documentation requirements for analytical procedures will assure that facilities are able to obtain and report accurate emissions

measurements.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 13

Comment: EPA should further clarify that any testi ng that may be required for process vent emissions best described by wastew ater calculation methods need to conform to the process vent realities. Typically, re porters use WATER9 type models to describe emissions from aqueous systems in conveyances other than hard piped syst ems. A number of these systems exist in the fluorochemical manufacturing indus try, including weak acid handling systems. Such systems may contain FGHGs, and some of those F GHGs could potentially become emitted. The appropriate testing for such a system consists mostly of EPA wastewater methods in publication SW-846. Typical source testing programs based on Method 18 typica lly require higher airborne concentrations, typically over between 1 and 20 parts per million by volume (“ppmv”), to detect compounds of interest. Directly measuring liquid FGHG concentr ations in such an aqueous stream, and calculating actual emissions from liquid analyses, provides more accurate and verifiable emissions calculations in these aque ous systems. We recommend that EPA provide adequate testing flexibility to fully document th e variety of aqueous process vent systems, and FGHG emissions from those systems, in the fluorochemicals industry.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

106

### Commenter Name: Lorraine Krupa Gershman


### Commenter Affiliation: American Chemistry Council


### Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 15

Comment: The testing protocols prescribed in §98.123(b)(4) do not allow for the development of site-specific protocols, nor do they allow for a change in protocols by the facility. We believe that the testing protocol la nguage in the Miscellaneous Or ganic Chemical Manufacturing

National Emission Standard for Hazardous Air Pollutants (NESHAP) (MON) (40 CFR 63.2450(g)) would have been sufficient with resp ect to testing. These protocols are already known and used by the chemical industry, and as such, would reduce the burden on reporting

facilities.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 4

Comment: 6. The analytical methods that are used for Subpart L should be modeled after the language that was developed during th e Subpart OO settlement process.

Response : Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 32

Comment: EPA proposes at proposed §98.124(c)(4)(vi) to require reporters using alternate source testing methods to implement Method 301 as a method validation protocol. DEECO, Inc., one of Arkema’s primary stack testing contractors informed us that the cost of running a single day of Method 301 compliant testing is $10,000, as opposed to ar ound $3,000 per day of standard Method 18 based source testing. EP A should only require Method 301, or other acceptable test acceptance criteria methods, to be performed during the first testing program using a new method. EPA should not require reporters to incur unnecessarily expensive testing protocols once a method has been proven reliable.

Response: By allowing additional methods and analytic al techniques to be us ed, as described in the final rule, EPA generally ex pects to reduce the economic burde n placed on facilities. It was not EPA’s intent to require a Method 301 validat ion test for a method every time an alternative

107method is used; a facili ty may conduct the Method 301 (or othe r scientifically sound) validation

the first time the alternative method is used for the an alyte(s) of interest at the concentration(s) of interest, and then use the altern ative method for the next testing requirement for those analytes and concentrations. A facility would not be requ ired to re-validate a method for the same set of analytes and concentrations.

Method 301 includes optional procedures that may be used to expand the applicability of the alternative analytical method. Section 7.0 involves ruggedness tes ting (Laboratory Evaluation), which demonstrates the sensitivity of the method to various parameters. Section 8.0 involves a procedure for including sample stability in bias and precision for assessing sample recovery and analysis times; Section 9.0 invol ves a procedure for the determin ation of the practical limit of quantitation for determining the lower limit of the method. These optional procedures are required for the waiver consideration outlined in Section 12.0 of Method 301. Although we are not incorporating such a waiver process in subpart L, §98.124(e)(3) requires a description of the validation protocol used to validate the alterna tive analytical methods. This would include a description of any methods used to expand the applicab ility of the alterna tive analytical method, such as those in sections 7.0, 8.0, and 9.0 of Method 301.

[Where did this move to?] Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 30

Comment: Section 98.124(c)(4)(v ) limits industry standard detec tion devices. EPA: Section 98.124(c)(v) states: “Use EPA Method 18 (with GC and either Mass Spec (MS) or Electron Capture Detector (ECD)”. Comment: Industry standard analytical practices use detectors other

than MS or ECD.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 29

Comment: The analytical methodologies set forth in the proposed rule are overly prescriptive and limit industry standard detection devi ces. Section 98.124(c)(4 )(v) & (vi) states:

(v) Fluorinated GHG concentrations. Use EPA Me thod 18 (with GC and either MS or ECD) in Appendix A–1 of 40 CFR part 60; EPA Method 320 in Appendix A of 40 CFR part 63; Draft EPA DRE Protocol; or ASTM D6348–03 (incorporated by reference in §98.7).

108(vi) Alternative fluorinated GHG concentration methods. Alternatives that may be used for determining fluorinated GHG concentrations in clude EPA TO–15 or other alternative test methods conducted in conjunction wi th EPA Method 301 for validation.

The EPA methods, such as EPA TO-15, do not wo rk well for fluorocarbons. Industry standard analytical practices use detectors other than MS or ECD. ECD is not as sensitive to fluorine as FID, for example.

We urge EPA to allow for the use of generally accepted analytical measurement technologies, including but not limited to gas chromatography with an appropriate de tector, nuclear magnetic resonance, infrared, etc. We also believe th at any acceptable analytic method validated using EPA Method 301 or another scientifically sound validation protocol (i ncluding manufacturer specifications or recommendations) should be allowed.

Whatever analytical measurement technologies and analytical methods are used should be documented and described in the facility’s GHG Monitoring Plan requir ed under §98.3(g)(5) of

the rule.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 33

Comment: Proposed §98.124(c)(4)(v) requires reporters to util ize a Method 18 (40 CFR 60 Appendix A) method to evaluate FGHG concentr ations. However, Method 18 does not allow use of Summa canisters for sample collection, instead requiring use of Tedlar® bags. DEECO reported to Arkema that SUMMA canisters provid e superior Method 18 performance to Tedlar bags, especially when evaluating complex ch emistry like FGHGs. EP A should indicate in proposed §98.124(c)(4)(v) that an appropriate sample collection sy stem shall be used, including direct injection, Tedlar bags or equivalent, and Summa canisters or equivalent. Other methods may emerge as appropriate as the reporting comm unity conducts the first round of FGHG testing in 2011. EPA should provide a mechanism allowing re porters to modify test methods to adapt to emerging realities that will beco me evident during testing.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103,1 Comment Excerpt Number : 31

109Comment: Analytical methodologies ar e overly prescriptive. EPA: Subpart L at 124(c)(4)(v) & (vi) says:

“(v) Fluorinated GHG concentrations. Use EPA Method 18 (with GC and either MS or ECD) in Appendix A–1 of 40 CFR part 60; EPA Method 320 in Appendix A of 40 CFR part 63; Draft EPA DRE Protocol; or ASTM D6348–03 (incorporated by reference in §98.7). (vi) Alternative fluorinated GHG concentration methods. Alternatives that may be used for determining fluorinated GHG concentrations in clude EPA TO–15 or other alternative test methods conducted in conjunction wi th EPA Method 301 for validation.”

Comment: The EPA methods, such as EPA TO-15 as written don’t work well for fluorocarbons.

ECD is not as sensitive to fluor ine. The following is suggested:

“(v) Analytical Methods. Use a quality-assure d analytical measurement technology capable of detecting the analyte of interest at the concentr ation of interest and use a procedure validated with the analyte of interest at the concentration of interest. Wh ere standards for the analyte are not available, a chemically similar surrogate may be used. Acceptable analytical measurement technologies include but are not limited to gas chromatography (GC) with an appropriate detector, infrared (IR), fourie r transform infrared (FTIR), and nuclear magnetic resonance (NMR). Acceptable methods include EPA Method 18 in Appendix A-1 of 40 CFR part 60, EPA Method 320 in Appendix A of 40 CFR part 63, the Draft EPA DRE Protocol, ASTM D6348-03 (incorporated by reference in §98. 7), or other analytical met hods validated using EPA Method 301 or some other scientifically sound validation protocol. The validation protocol may include analytical technology manufacturer specifications or recommendations. (vi) Documentation in GHG Monitoring Plan. Describe the analytical method(s) used under paragraph (n) (1) in the site GHG Monitoring Plan as required under §98.3 (g) (5) of this part. At a minimum, include in the descri ption of the method, a description of the analytical measurement equipment and procedures, quantitative estimates of the method’s accuracy and precision for the analytes of interest at the concentrations of interest, as well as a description of how these accuracies and precisions were estimated, in cluding the validation protocol used.”

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number : 12

Comment: Detection of fluorinated greenhouse gases in plant e nvironment at the precision required does not exist in many cases. Reporting f acilities may need to develop customized fugitive and stack emissions testing protocols not fitting the prescribed EPA test methods proposed in Subpart L. EPA should provide a m echanism for reporting facilities to resolve emerging technical issues that ma y not fit existing procedures.

110Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30 and to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 1.

Section 5.5 - Calibration Standards

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 31

Comment: Section 98.124(l) calls for monthly calib ration of all analytical equipment. Preparation of new controls over the full range of calibrated components for each test on such a frequency would be prohibitive from both a cost and manpower basis. Historically, an annual calibration check has proven to be sufficient to achieve accuracy levels equivalent to those specified in EPA methods.

In most cases certified calibration standards are not available for our products. In those cases where they are not, there are genera lly three methods that are used:

1. Gravimetrically mixing known amounts of pure individual chemical species; 2. If pure individual chemical sp ecies are not available, process material (product) are collected and held as a historical reference against which instrument response is checked for stability; or 3. If neither pure chemical nor product is available, then surrogates can be used.

The protocol involves gravimetric measuremen t of known amounts of the chemical as noted above, diluted to appropriate concentrations.

We urge EPA to allow facilities to calibrate analytical fre quency as needed to support the requisite analysis. The calibra tion frequency and method should be documented and described in the facility’s GHG Monitoring Plan required under §98.3(g)(5) of the rule

.

Response: The monthly calibration requirement fr om the re-proposal rule for analytical equipment has been revised to require a calib ration frequency and meth od that supports the validated analytical method chosen by the facili ty. When certified calib ration standards are not available, which commenters have noted is common for fluorinated GHGs, facilities may use mixtures of pure individual chemical species, pro cess material, or a chemically similar surrogate compound for the calibration event. This is the typical and accepted practice for many

fluorinated GHGs. The calibration frequency and method must be sp ecified and explained in the facility’s GHG Monitoring Plan.

111Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 8

Comment: Certified standards for refrigerant gases and associated impurities are not available. §98.124(l) requires that certifi ed standards be used in the calibration of a ll analytical equipment

used to determine the concentration of fluorinat ed GHGs. §98.124(a) requir es an initial scoping study to identify all fluorinated GHGs that may be generated from processe s subject to Subpart L

and that have uncontrolled emissions of 1.0 me tric ton or more of fluorinated GHGs. The paragraph further requires that the scoping study must be performe d on the streams that would be expected to contain all fluorin ated GHG by-products of the process. Therefore, as proposed, no fluorinated GHGs are exempt from being identified using one of the analytical methods listed in §98.124(c)(4)(v).

Mexichem’s laboratory has not found a source fo r certified refrigerant gases (product or impurity). Standards are made in Mexichem’s on-site laboratory by diluting pure product (obtained from a third-part y laboratory) to the app licable concentration.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 31.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 56

Comment: EPA proposed a limited number of tes ting options at proposed §98.124(k). Some of these methods may or may not be appropriate for the number and types of vents that may need to be sampled, based on the scoping test results to be developed in calendar year 2011. Arkema understands that EPA is developi ng alternate testing language for other Part 98 subparts that may provide sufficient flexibility. Technical issues that may arise include conflicts between §98.124(k) American Society for Mechanical E ngineers (“ASME”) calibration methods and instrument appropriate calibrati on methods, listed §98.124(c)(4) test methods in lieu of preferred EPA 40 CFR 60 Appendix A (or other EPA) test methods, technical limitations that govern the use of specific detection technology for some ta rget FGHGs outside of the proposed testing limitations, and the lack of certified standards fo r some target FGHGs as required in proposed §98.124(l). Absent a testing protocol process for reporters to c oordinate testing with EPA, Subpart L should include a methodology for reporters to utilize alternate test methods when required. EPA should also evaluate testing and analytical equipment pe rformance requirements in Subpart OO in effect when Subpart L comp liance begins to harmonize testing obligations between these two fluorochemical subparts.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 30.

112As proposed, the final rule allows use of either the lis ted consensus standard calibration methods

or calibration methods recommende d by the flow meter, weigh-scal e, or other volumetric or density measure manufacturer. We have conclu ded that this allows ample flexibility while ensuring that measuring devices are appropriately calibrated. Regarding harmonization with subpart OO, EPA has modified th e testing requirement language su ch that it is more closely aligned with the proposed amendments to subpa rt OO and provides the same flexibility.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103,1 Comment Excerpt Number : 37

Comment: Section 98.124(l) Instrume nt calibration frequency is excessive. EPA: Proposed section 98.124 (l) states:

“(l) All analytical equipment, including gas chromatographs, GC/MS, GC/ECD, FTIR and NMR devices, used to determine the concentration of fluorinated GHG in streams shall be calibrated at least monthly through analysis of certified standards with known concentrations of the same chemicals in the same ranges (fractions by ma ss) as the process samples. Calibration gases prepared from a high-concentrati on, certified standard using a gas dilution system that meets the requirements specified in Method 205, 40 CFR Part 51, Appendix M may also be used.”

Comment: Preparation of new c ontrols over the full range of ca librated components for each test on such a frequency would be prohibitive from bot h a cost and manpower basis. Historically, an annual calibration check has proven to be sufficien t to achieve accuracy levels equivalent to those specified in EPA methods. If standards can be used as described below (typically using standards that were prepared previously) monthl y calibration might be more reasonable. In most

cases certified calibration standard s are not available for our produc ts. In those cases where they are not, there are generally three methods:

1. gravimetrically mixing known amounts of pure individual chemical species 2. where pure individual chemical species are no t available, process ma terial (product) are collected and held as a historical reference ag ainst which instrument response is checked for stability 3. if neither pure chemical nor product ar e available, then surrogates can be used.

The protocol involves gravimetric measurement of known amounts of the chemical noted in #1, 2 or 3, above, diluted to appr opriate concentrations. The follo wing wording is suggested:

“All analytical equipment used to determine the concentration of FGHGs, including but not limited to gas chromatographs and associated de tectors, IR, FTIR and NMR devices, used to determine the concentration of FGHG in streams, shall be calibrated at a frequency needed to support the type of analysis specified in th e site GHG Monitoring Plan as required under §124(c)(4) and §98.3 (g) (5) of this part. Quality assurance samples at th e concentrations of

113concern shall be used for the calibration. Such qua lity assurance samples sh all consist of or be prepared from certified standards of the analytes of concern where availabl e; if not available, calibration shall be performed by a method sp ecified in the GHG Monitoring Plan.”

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 31.

Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 11

Comment: Clarify whether th e calibration requiremen ts of §98.124(k) apply to equipment used to measure process activity. Under the site-s pecific process-vent-spe cific emission factor approach, process activity measurem ents must be determined using flow meters, weigh scales, or

other measurement devices or instruments with an accuracy and precision of ±1 percent of full

scale or better. It is not cl ear whether the calibration requirem ents of §98.124(k) apply to these

devices and/or instruments.

Response: The calibration requirements in §98.124(m) [§98.124(k) in the April 2010 proposed rule] do apply to the monitoring instrument s used to measure process activity.

Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 12

Comment: Clarify whether equipment used under the Best Available Monitoring Methods (BAMM) of §98.124(m) must be calibrated in acc ordance with the provisions of §98.124(k) and (l). It is not clear whether equipment used under BAMM needs to be calibrated prior to January 1, 2011 and as required throughout the BAMM period.

Response: Under §98.124(o) of the final rule [form erly §98.124(m) in the April 2010 proposed rule], facilities may use the best available m onitoring methods between January 1, 2011 and June 30, 2011 without submitting a request. To the extent possible, facilities must meet all requirements specified within subpart L, even wh ile using BAMM. In the event that the best available monitoring method at a pa rticular facility is unable to comply with the calibration requirements specified in §98.124 (m) and §98. 124 (n) [formerly §98.124(k) and (l) in the proposed rule], use of an altern ative calibration procedure would be appropriate for the duration of time during which that facility was authorized to use BAMM.

114Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 28

Comment: The section 98.124(b) process measurement devices annual calibration is excessive. EPA: Section 98.124(b)(1)(i) st ates: “...using the methods and measurements set forth in §98.413(a) and (b) and in section 98.414(a) and (b ).” Comment: The mass balance approach requires following the vendor recommended calibra tion frequency. Some flow meters cannot be calibrated on-line. This could impact up time si nce in many cases a shutdown is required for calibration. It could take 2 years to calibrate some flow meters ba sed on shut-down frequencies.

Response : The calibration frequency in the final rule has been revised to the frequency recommended by the instrument manufacturer. In order to maintain high data integrity levels, EPA requires that the calibrations be performed on a regular basi s. Depending on the instrument manufacturer’s recommended frequency, this ma y or may not coincide with process shutdown periods, but EPA anticipates that the majority of manufacturers have scheduled production and shutdown periods to allow calibra tion at regular and/or required frequencies. Moreover, EPA anticipates that most manufacturer s will have calibrated the instru ment (or verified a calibration performed by the instrument manufactur er) before putting it into service.

Section 5.6 - Destruction Devi ce Efficiency Determination

Section 5.6.1 – Destruction Device Testing

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 17

Comment: §98.124 (f), Destruction device performan ce testing. We are requesting that the testing frequency be increased to ten years (10) or whenever operation conditions would have been expected to substantively change the expect ed performance of the destruction device. The thermal treatment devices that may be used to tr eat process emissions in this source category will utilize process control monitoring that would identify decreases in process performance. We do not expect that the performance of the system will change with time or would change in a manner that would not detected by this type of instrumentation pr ocess instrumentation.

Response: We agree with commenter that a 10- year frequency for conducting destruction device performance testing is appr opriate and have revised the fre quency requirement in the final rule. For substantive changes that may affect the destruction efficienc y, the final rule also requires re-testing to determine the revised dest ruction efficiency. This combined approach reduces the testing burden to facilities while at the same capturing destruction device changes that may occur.

115

### Commenter Name: Rich Raiders


### Commenter Affiliation: Arkema Inc.


### Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 42

Comment: Second, EPA should clarify that retesting a control device that will continue to meet the appropriate 99.9% or 99.99% DRE need not be retested until the next scheduled five-year testing cycle.

Response: Regarding the frequency of testing, pl ease see the response to comment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 17. Rega rding the 99.9 percent destruction efficiency that was included in the April 2010 pr oposed rule as a criterion for allowing use of

emission calculation factors to estimate emissions fr om process vents, plea se see the preamble of

the final rule.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 35

Comment: Destructability. Proposed §98.124(f) requires reporters to evaluate destructability of identified FGHGs to evaluate controllability of the FGHG stream. Typically, we identify the autoignition temperature (“AIT”) of each identif ied species to set a th ermal oxidizer operating temperature. However, not all AIT values for the variety of FGHGs be ing controlled today, or potentially being controlled in the future, are kno wn at this time. Repor ters utilize surrogate compounds to calculate AIT values in designing thermal oxidizer operating parameters based on known combustion chemistry. Surrogates within similar molecular weight, similar bond structure, and similar co nstituent molecules are appropriate as test proxies. FGHGs follow very specific composition designs of hydrogen, carbon, and fluorine. Similarly structured higher molecular weight molecules tend to have lower AITs, and are more easily destroyed, than smaller similarly structured molecules. EPA should clarify that the §98.124(f)(1) AIT requirement only applies for FGHGs with known AITs. EPA should allo w testing verified performance for Subpart L compliance, regardless of how an individual emission control system may have been designed. EPA should also clarif y that AIT determination is not necessary for any FGHG comprising less than 0.1% of a combined vent stream because destruction of trace

constituents cannot influence DRE.

Response: A response regarding the use of surro gate compounds in destruction device performance testing has been provided in section II. E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Pro duction (Subpart L)).

The final rule has also been modified to exclude gases that occur at or below trace concentrations

in streams fed into th e destruction device.

116Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 36

Comment: Arkema appreciates EPA’s recognition of the interplay between Subpart L and the Hazardous Waste Combustion (“ HWC”) maximum achievable co ntrol technology (“MACT”) standard at 40 CFR 63 Subpart EEE. The AIT discussion above also applies to the principal organic hazardous constituent (“POHC”) analysis required at proposed §98.124(f)(4). The identified POHC may or may not have consid ered FGHGs with unknown AITs. However, as HWC regulated units must demonstrate 99.99% cont rol efficiency every five years per 40 CFR 63.1207 (for RCRA incinerators). EPA should allo w reporters to use existing comprehensive performance test (“CPT”) results showing P OHC DRE compliance in lieu of the POHC requirements. EPA should clarify that §98.124 (f)(4) only concerns FGHGs with known AITs that comprise more than 0.01% of a combined stream controlled by a HWC MACT compliant

combustion unit.

Response: A response regarding the use of surro gate compounds in destruction device performance testing has been provided in section II. E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Producti on (Subpart L)). In the fi nal rule, §98.124(g)(3) [formerly §98.124(f)(4) in the re-proposed rule] has been modified to allow facilities to apply the destruction efficiency determined for specifi c compounds in conjunction with the Hazardous Waste Combustion MACT in 40 CFR 63 subpart EEE, as long as specific criteria for compound selection in §98.124(g) are met. The selection of a surrogate(s) used in 40 CFR 63 subpart EEE testing must meet the criteria in §98.124(g)(1) fo r the most difficult to destroy compound in the vent to allow applicatio n of the DE from that program to the emission estimates for subpart L.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103,1 Comment Excerpt Number : 34

Comment: EPA should replace the proposed requirem ent to use the “most-difficult-to-destroy fluorinated GHG” during DRE testing with a re quirement to use a fluorinated GHG (F-GHG) representative of the most difficult to destroy FGHG burned in the device. EPA: In the proposed 40 CFR 98.124(f)(1), EPA would require destruction effici ency testing “when destroying the most-difficult-to- destroy fluorinated GHG (or a su rrogate that is still more difficult to destroy)” fed to the device. For devices destroying chlorofluorocarbons (CFCs), the

Montreal Protocol and related Clean Air Act regulations restrict the availability of many CFCs in

concentrated form to facilitate known FGHG injection for DRE testing. Moreover, EPA has adopted a thermal stability index developed by th e University of Dayton Research Institute to rank organic chemicals (including FGHGs) into classes according to their difficulty to destroy (Appendix D of EPA’s Guidance on Setting Permit Conditions and Reporting Trial Burn Results, January 1989, EPA/625-6-89/019). Co mment: With this thermal stability index, EPA allows

117DRE testing of an available Class 1 chemical to demonstrate DRE for all Class 1 (and lowernumbered classes of) chemicals. Similarly, su ccessful DRE testing for a Class 2 chemical demonstrates DRE for all Class 2 (and lower-num bered classes of) chemicals. EPA has codified this approach in 40 CFR 1219(c)(3)(ii) requiri ng DRE testing with a compound “representative of the most difficult to destroy organic compoun ds.” Therefore, EPA should replace the second sentence of the proposed 40 CFR 98.124(f)(1) with the following: “To determine the destruction efficiency, emission testing shall be conducted wh en operating at high loads reasonably expected to occur (i.e., representative of high total fluor inated GHG load that will be sent to the device) and when destroying a chemical representative of the most-difficult-to-destroy fluorinated GHG

that is fed into the device from th e processes subject to this subpart.”

Response: A response has been provided in section II.E.3 of the preamble to this rule (see section II.E, Fluorinated Ga s Production (Subpart L)).

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 17

Comment: §98.124 (f) (3) Part 264, 266, and 270 prin cipal organic hazardous constituent (POHC) testing, and (4) Hazardous Waste Combustor. In 3M’s comments to the original proposed rule in correspondence dated June 9, 2009, 3M discussed the impact that these rules had on its Corporate Incinerator. The comment la nguage from that document is provided below:

“3M has several facilities that produce materi als that would be cons idered fluorinated- GHG

materials under the rule definitions. One of thes e sites is also the home of a 3Mowned hazardous waste incinerator that is a stand-alone facility used to reduce the volume and toxicity of wastes that are generated in 3M manufacturing operations around the country. Currently under §98.126, reporting is required for materials that are shipped offsite for dest ruction. 3M is concerned that the rule could be read to requi re an annual DE test at this company-owned incinerator solely because wastes containing fl uorinated-GHG, that are gene rated in some manufacturing operations at that same location, would be shipped to that incinerator instead of to an off-site

incinerator for destruction. Such a DE test would not be required at third-party incinerators. It would be an unfair burden to require the 3M-owned incinerator to conduct these tests. Since all

hazardous waste combustion facilit ies currently conduct rigorous tr ial burns, all incinerators should be exempt from the DE testing requirement s, irrespective of whet her the incinerator is collocated with a manufacturing operation or is off-site from such an operation.

As a general point, many solid wastes from fluorinated-GHG production processes are treated and completely destroyed in hazardous waste in cinerators that are permitted and meet the requirements of 40 CFR Part 264. These facilities provide an extremely high degree of mitigation for fluorinated-GHG as they must conduct periodic trial burns under worst-case operating conditions, e.g. lowest operating temper ature, which demonstrate greater than 99.99% destruction of Principal Organic Hazardous Constituents (POHC). POHC’s have been identified as those organic compounds which are the most r ecalcitrant to thermal degradation. These tests

118are exhaustive studies that are intended to pr ovide a clear demonstrat ion of the facilities’ capabilities and that are typically conducted at five year intervals.

In addition, waste incinerators are required under 40 CFR 264 and 40 CFR 63 MACT standards

to utilize state-of-the-art emi ssions control practices and work practice standards to control emissions from waste management activities which will occur prior to incineration. EPA recognized the effectiveness of waste incinera tors in the “Technical Support Document for Industrial Gas Supply: Production, Transformati on, and Destruction of Fluorinated GHGS and

N 2 0. Proposed Rule for Mandatory Reporting of Greenhouse Gases.” (February 6, 2009).

3M believes that existing trial burn met hodologies and other EPA requirements governing hazardous waste incinerators provide sufficient de monstration of the destruction of fluorinated GHGs. As such, 3M requests that any fluorinated GHGs that are managed are facilities subject to the provisions of 40 CFR Part 264 should be ex empt from any reporting requirements. For the purposes of reporting, it should be assumed th at these materials are totally destroyed.”

3M’s Corporate Incinerator functions as a stand alone facility. This is a typical rotary kiln incinerator with multiple waste feeds and having the capability of adding liquids, sludges, and solids that are transported to the facility in bu lk tankers and various sized containers. There are

no direct connections between this incinerator and any vents or pi pelines that originate in the fluorinated-GHG production areas at the site. Wastes from the fluorinated-GHG facility which

meet the definition of a fluorin ated-GHG would be placed in c ontainers, most commonly 55- gallon drums and 5-gallon pails, an d transported in van trailers to the incinerator where they would be stored prior to dispos al. In the reproposed Subpart L, EPA referenced the performance tests conducted by hazardous waste incinerators in §98.124(f)(3) Part 264, 266, and 270 principal organic hazardous constituent (POHC) te sting and §98.124(f)(4) Hazard Waste Combustor testing. 3M has a number of concerns with the re quirements in this section. We would reiterate our original comments that these requirements unfairly target faciliti es that happen to be collocated with fluorinated-GHG production facil ities. These requirements would not apply to third party and/or commercial incinerators a nd they would not appl y to corporate owned

incinerators that are not located on the same site . This facility may also be unique from other onsite incinerators in this source category in that the incineration process has no direct connection to the manufacturing processes and the qua ntity of wastes that are generated from the affected processes at the site c onstitute a small amount of the waste that is incinerated at the facility.

An alternative method that EPA could use to ad dress this concern would be to modify the language contained in §98.124(f)(1 ) through (4) so that it refl ects the current practice and interpretation of the performance tests that are conducted at the fac ilities subject to the provisions of paragraphs (3) and (4). This includes the fre quency of this testing and the manner in which the principal organic hazardous constituent (POHC) s hould be used to demonstrate compliance with the 99.99% percent destruction. Paragr aph (2) of that section requires testing within the last five years prior to the effective da te of this rule. Subpart EEE (par. 4) provides for having to demonstrate compliance with the DRE standard on ly once provided the so urce is not modified

after the DRE test in a manner that could affect the ability of the source to achieve the DRE standard. Currently RCRA rules (par . (3)) require testing at least once every 10 years as part of

119the RCRA permit renewal. The DRE test is a co mplex and costly endeavor which requires significant planning and coor dination. We recommend that this se ction be revised to indicate that testing must be completed at a frequency which is consistent with the applicable federal or state

standards.

Additional clarification is also re quired in this section to insure that any Class 1 POHC’s is an adequate surrogate for the “....most-difficu lt-to-destroy fluorinated-GHG fed into the device...”In the rule preamble, EPA indicates that surrogates can be used for the DRE demonstration. While the “surrogate ” reference is contained in para graph (f)(1) of this section, a similar reference is also required in paragraph (3 ) and (4) of that section. More importantly, EPA should clarify that Class 1 POHC’s are accepta ble surrogates. Methodologies for selecting and approving POHC’s for DRE testing have been in place for some time (9). The selection of

chemicals for trial burns is base d on a number of factors includi ng the incinerability ranking or presence and amount in waste feed s. The POHC thermal stability rankings are contained in the referenced document and are based predominan tly on experimental studies conducted at the University of Dayton, studies reported in the open literature, and theoretical considerations, These chemicals have been grouped into seven classes based on thermal stability and as a practical manner, demonstration of a 99.99% DR E for a POHC in a class of higher thermal stabilities is adequate to allow incineration of ch emicals contained both in that class in all lower

classes. DRE demonstration for Class 1 chemicals adequately addresses all chemicals on this list. 3M’s Corporate Incinerator conducted its trial burn using several POHCs. These included naphthalene (Thermal Stability Index: 5 (Class 1)) and the facility de monstration of DRE of greater than 99.99987. Testing on POHC’s with lo wer stability indices had greater DREs.

3M believes that this information provides su fficient demonstration th at all fluorinated-GHGs that are being incinerated at the facility are adeq uately destroyed and insigni ficant with respect to total inventory emissions. Proper clarification on th e meaning of surrogate will insure that these performance tests are consistent with accepted pr actices in the industry. We are providing two

references where the incineration of SF6 wa s evaluated in hazardous waste combustion processes. SF6 as an thermal stability index that is roughly equivalent to naphthalene and there is

information in the literature which demonstrates a high degree of dest ruction in these RCRApermitted units. (10,11)

Response: A response regarding the use of surro gate compounds in destruction device performance testing has been provided in section II. E.3 of the preamble to this rule (see section II.E, Fluorinated Gas Pr oduction (Subpart L).

The requirement to monitor and re port fluorinated GHG emissions from incinerators that are colocated with fluorinated gas production processes is consistent with the Mandatory GHG Reporting Rule’s general requirement to monitor and report emissions from all of the source categories at facilities whose emissions exceed the 25,000 mtCO 2 e threshold. Please see the October 30, 2009 final rule (e.g., the response to comments regarding de minimis reporting) for more discussion of this policy.

We did not propose to require monitoring and reporting of fluorinated GHG emissions from

incinerators and other de struction devices that are not co-loc ated with fluorinated gas production

120processes. This was because to tal emissions of fluorinated GHGs from such facilities appeared likely, in general, to be small. However, we c ould consider requiring from such incinerators if subsequent research or data indicated that these conclu sions were not correct.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 32

Comment: Trace components need to be exempted fr om the Destruction Requirements. EPA: Section 98.124(f)(1) states “ You mu st sample the inlet and outlet of the destruction device for a

minimum of three runs of 1 hour each to dete rmine the destruction efficiency” Comment: Achieving the prescribed DRE for small trace components may not be feasible. We suggest wording such as “Estimate annually the total mass of each fluorinated GHG emitted from

destruction of fluorinated GHGs ...Trace FGHGs in the destruction device influent are exempt from this section.” A section 98.122 exempti on for trace components would streamline and clarify application of an exem ption, and would be preferred.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 35.

Section 5.6.2 - Detection Limit Issues

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 20

Comment: EPA should also address a potential DRE testing condition that arises from time to time where a DRE calculation is impossible. In many situations, a control device operates so effectively that, during testing, the outlet con centration is below the method detection limit

available from the test method. In these situations, as the cont rol device outlet concentration is reported as less than the quantitation limit, an actual DRE calculation is not possible. EPA should note in regulatory language that outlet concentrations belo w an appropriate concentration threshold meet DRE requirements. In HON, EPA set this default concentration minimum by rule at 20 parts per million by volume (“ppmv”). EPA should provide reporters the option of reporting a minimum control device outlet conc entration in lieu of a DRE value.

Response: Several commenters suggested that EPA develop an approach for determining the destruction efficiency when the outlet concentr ation of the destructi on device is below the method detection limit. We have revised §98.124 (g) in the final rule to allow use of a

concentration that is one-hal f of the method detection limit in estimating the destruction efficiency. While using an outlet minimum c oncentration, for example the 20 ppmv mentioned by the commenter, is commonly used as a complia nce option for regulations , in this situation

121what is needed is a reasonable, documented destruction efficiency, not necessarily a

demonstration that the destruction device meets a particular limit.

Section 5.6.3 - Hazardous Waste Combustors

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number : 53

Comment: EPA should also clarify that HWC MACT units undergoing an automatic waste feed cutoff (“AWFCO”) need not report under this provision, as AWFCOs are designed to prevent emissions from occurring from a hazar dous waste combustor that is not operating properly. Facilities may not route FGHGs, or any other materials, to RCRA combusters until the cause of an AWFCO has been repaired. Because reporters must tract AWFCO activity for other EPA Clean Air Act obligations, EPA can review AWFCO activity to verify the lack of FGHG emissions during combustor shutdown events.

Response: EPA would like to note that emission s of all fluorinated GHG emissions from fluorinated gas production and transformation proce sses covered in the source category must be reported. As the comment states, during AWFCO pe riods, no materials may be routed or vented

to the hazardous waste combustor. If these ar e bypass events or periods when uncontrolled

fluorinated GHG emissions are vent ed to the atmosphere, then certainly the facility must account for these emissions, probably as malf unction emissions under §98.124(i). Industry has noted that some processes include holding ta nks or operating modes that allow continued operation during destruction device downtime or ma lfunctions, either until the combustor can be brought back online or until shutdown of the process can be completed. In this situation, emissions are not vented to the atmosphere. In dustry has noted that for some processes and fluorinated GHGs, there are never any bypass events because the facility is not authorized for such an event. Industry has noted that fluor inated GHG emissions from a process would be routed away from the hazardous waste combustor to another destruction device, for example a

thermal oxidizer. In this situa tion, the facility coul d potentially estimate emissions based on the demonstrated DE for the other control device, or if no demonstrated DE is available, then assume the emissions are uncontrolled. Another alternative for the facility may be to define an operating scenario for periods when fluorinated GHG em issions are vented to the hazardous waste combustor, and define another operating scenario for periods when venting to another control device, if this is a regular event.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103,1 Comment Excerpt Number : 33

122Comment: Consistent with MACT standards fo r hazardous waste combustors, EPA should

allow one-time DRE demonstration for F-GHG for destruction devices with a flame in place of the proposed requirement for such testing every five years. EPA: In the proposed 40 CFR 98.124(f) and at 75 FR 18680, “EPA is proposing to require fluorinated gas producers that destroy fluorinated GHGs to conduct an emissions test every five years to determine the destruction efficiency (DE) of the destruction device.” Comment: Based on extensive review of DRE (destruction and removal efficiency) perf ormance at controlled flame hazardous waste combustion devices, EPA concluded that repeat DRE testing was not necessary for devices that

do not feed waste in a location other than the fl ame zone as codified at 40 CFR 1207(c)(2)(iv) and 40 CFR 1206(b)(7)(ii). The appropr iate exception from one-time DRE testing would the sort of process change described at existing propos ed text for 40 CFR 98.124(f)(5). Therefore, 40 CFR 98.124(f) should be revised in the final rule to not require DRE testing more than once (except as noted at 40 CFR 98.124(f)(5)) and to delete the phrase “within the last 5 years prior to

the effective date of this rule” from the final 40 CFR 98.124(f)(2).

Response: It is our understanding that 40 CFR 63 subpart EEE requirements include a one-time confirmatory performance test for dioxin/fura n compounds for certain boiler types and fuel types, and include a comprehensiv e performance test every 5 year s for other pollutants that may include metals (mercury, cadmium, lead, arsenic, beryllium, chromium), CO, HC, HCl, total chlorine, and PM. For those sources that feed hazardous waste to the normal flame zone, an initial comprehensive performance test to demonstrate the DRE would be conducted, and subsequent comprehensive performance testing would not require demonstration with the DRE standard if there were no changes to the source that would affect the ability to achieve the DRE standard. (For cement kilns that feed hazardou s waste to the normal flame zone, facilities must conduct the DRE testing for three consecuti ve comprehensive performance tests.)

The DRE testing conducted under a part 63 subp art EEE comprehensive performance test may be used for subpart L purposes if the HWC testing meets the requi rements for §98.124(g)(1)(i) through (iv). If hazardous waste is fed to th e normal flame zone and DRE testing is not conducted every 5 years, facilities may use th e destruction efficiency from the latest comprehensive performance test under part 63 subpart EEE as long as there have been no changes to the design, operation, or maintenan ce of the destruction device since the last destruction efficiency test that could affect the destruction efficiency.

Section 5.6.4 - Process Scrubbers Considered Destruction Devices

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 17

Comment: 3M recommends that water scrubbers be specifically excluded from the destruction

device definition and that all emission assessments for such devices be made at the outlet of the unit. Water scrubbers are used in many of these ma nufacturing areas either as a primary or backup air pollution control device. The scrubbers are designed to remove hydrof luoric acid and acid

123halides (primarily carbonyl fluoride) that could be present in some of the process emissions. Carbonyl fluoride is very hygrosc opic and reacts quickly in the pr esence of water to form HF and carbon dioxide. This has been confirmed by various tests that have been conducted to document scrubber performance. These hydrolysable compounds are included in the 40CFR60.191

definition of Total Fluoride and can be measur ed using EPA Method 13A and 13B. Emissions of these compounds are limited unde r the PSD/NSR three (3) ton/yr significance threshold.

3M believes that carbonyl fluoride would be considered a fluorinated-GHG since it contains carbon fluorine bonds and its vapor pressure exceeds 4000 mm Hg at 25°C. The smaller amounts of other acid halides that would be present wi ll also have vapor pressures which exceed 1 mm Hg. In addition we also concerned that these sc rubbers would be considered destruction devices as defined in §98.6: “Destruction means, with respect to fluorinated GHGs, the expiration of a

fluorinated GHG to the destruction device actua lly achieved.” 3M ha s conducted performance tests for many of these scrubbers and due to the reactivity of these compounds they are commonly reduced to less than their method detection limits.

The same mechanism that results in their effective removal in pr ocess scrubbers will also limit the atmospheric lifetime of these chemicals. Aqueous phase mitigation will result in rapid

attenuation in the environmen t with very low lifetimes, e .g. 5-10 days being reported by a

number of inves tigators (5-8).

Response: The final rule does not require destructi on efficiency testing for wet scrubbers that are primarily in place for acid gas removal, either HF or HCl, as long as no appreciable reduction of fluorinated GHG occurs. Certainly, any water scrubber that is in se ries with a thermal destruction device and is in pl ace primarily for acid gas cont rol would not be required to determine the destruction efficiency, and water sc rubbers that are in pl ace as the primary or backup control device for acid gas removal would not be required to determine destruction efficiency either.

While this commenter notes that water scrubbers should not be incl uded as destruction devices, another commenter notes that they do use wate r scrubbers specifically to control fluorinated GHG, although they do not specify the compoun d controlled (see the response to EPA-HQOAR-2009-0927-0103.1, excerpt 35. To estimate emi ssions from a process where fluorinated GHG emissions are controlled by a water scrubber, a facility has three options under subpart L: (1) calculate or measure emissions before the water scrubber and do not apply any destruction efficiency to the emissions, (2) perform emission testing after the water scrubber under §98.124(c) to develop a process-vent-specific emi ssion factor that reflects the impact of the scrubber on the emissions, or (3) conduct destruction de vice performance testing under §98.124(g) to establish and apply a de struction efficiency for the scr ubber. We believe that these options provide ample flexibility to facilities in the manner in which they may account for any impact of water scrubbers on their fluorinated GHG emissions.

124Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Comment Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number : 5

Comment: 7. We are requesting additional language to exempt certain destruction devices from additional testing requirements under this rule.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0111.1, excerpt 17.

Section 5.6.5 – PIC Testing

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 35

Comment: To the extent that EPA decides to re quire reporting of by-product FGHGs from the destruction of CFCs or HCFCs, EPA should allow facilities to use reaction modeling, literature values, pilot-scale data, and/or lab- scale test data in lieu of full-scale testing as the basis for such reporting. EPA: At 75 FR 18680, EPA request s comment on whether the Agency should “require reporting of by-product fluorinated GHG emissions from destruction of CFCs and HCFCs.” Comment: A number of experimental and theoretical studies have been conducted to investigate products of incomplete combustion (PICs) from the incineration of CFCs. For example, abstracts for a number of publicati ons by EPA’s Office of Research and Development (ORD) describing their i nvestigations of PIC formation from CFC destruction are presented at http://www.epa.gov/appcdwww/aptb/abstracts/cfc.htm . During development of basic data for projects to install CFC and/or HCFC flame-based thermal conve rters, pilot-scale testing may have been conducted including determination of PICs. Furthermore, Wing Tsang and his colleagues at the National Institute of Sta ndards and Technology (NIST) have developed a comprehensive chemical kinetic mechanism and parameter database for C1 and C2 fluorinated hydrocarbon destruction in a flame environment that can be used to predict PICs and PIC concentrations; see Progress in Energy and Combustion Science, Vol. 21, pp. 453-529, 1996 and Combustion Science and Technology, Vol. 139, pp. 385-402, 1998 for a description of the mechanism, database, and related reaction modeli ng. EPA should allow faci lities to use reaction modeling or existing test data in place of full-scale testing if the Agency decides to require reporting of by-product F-GHGs from CFC or HCFC destruction. One of our plants performs FGHG destruction of organic acid fluorides via use of a water scrubber. Experience has been there is no newly created F-GHGs disc harged from this control device.

Response: We are not requiring testing of PIC forma tion from destruction of fluorinated gases in the final rule. We have, however, added a reporting requirement in 98.126(j) asking that facilities report any previous test ing or analysis they have conduc ted to determine the extent of

125126 PIC formation. This would be a one-time report. Please see the preamble of the final rule for

more discussion of this issue.

Section 6 - Procedures for Estimating Missing Data

No comments are associated with this issue.Section 7 Data Reporting Requirements

Section 7.1 Confidentiality Concerns

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 16

Comment: In [section] B, Fluorinated Gas Produc tion, Section 7 [of the preamble], EPA notes that facilities using the mass- balance approach would report the masses of the reactants, products, by-products, and wastes, and, if applicable, the quantities of any products in the byproducts and/or wastes. The chemical identities of reactants, products, and by-products also have to be reported, along with the chemical equati ons used to estimate emissions. Air Products advises that this information on yields, by-pr oducts and chemical equations is extremely sensitive, confidential bu siness information (CBI) that is para mount to market competitiveness. Air Products strongly recommends th at this data be maintained only at the respective industrial facility and only be provided fo r visual evaluation and validati on during on-site inspection. This is currently done with EPA’s Toxics Release Inventory.

Response: Because the mass balance approach ha s been revised to allow its use for transformation processes, the reporting requireme nts have changed somewhat since re-proposal; however, similar types of information must be monitored, recorded, and reported for the promulgated rule. See the preamble of the fina l rule and section 4.2 of this RTC document for discussion regarding changes to the mass balance approach. Those facilities that use the mass balance approach to estimate emissions are requ ired to submit data that includes the chemical equation that represents the production process an d the chemical identitie s and the total mass of the reactants, by-products, products , and streams that are dest royed and removed from the production process (by process). This informati on is necessary to verify the fluorinated GHG emissions. Facilities that use the site-specific pr ocess-vent-specific emissi on factor approach or the site-specific process-vent-specific emission calculation factor to estimate emissions must submit data on the mass of total product or othe r process activity data on which the emissions

factor and the emissi ons rate are based.

EPA is requiring reporting, rather than simply rete ntion, of this data in order to permit EPA to conduct an annual verification of the emissions qua ntities reported by each facility. Due to EPA resource constraints, it is unlikely that EPA would be able to make site visits annually to verify reports based on facility records. Without reporting of verification data, therefore, the frequency of verification would be lower, while the costs of such verification would be much higher. Nonetheless, EPA is aware of the commenters’ concerns and may consider moving certain requirements from the reporting section to the reco rdkeeping section of the rule following further analysis.

A brief discussion of EPA’s recent proposed Confid entiality Determination is provided in section II.B of the preamble to this rule (see section II. B, Overview of Confiden tiality Determination for Data Elements in the Mandatory GHG Reporting Rule). EPA published a proposed

127confidentiality determination on July 7, 2010 (75 FR 39094) which addressed this issue the CBI status of certain data elements. In that action, EPA proposed which specific data elements would

be treated as CBI and which data elements must be available to the public unde r section 114 of the CAA. EPA has received comments on the proposal and is in the process of considering these comments. A final determination will be issued before any data is released, and the final

determination will include all of the data elemen ts under these subparts. In addition to proposing the confidentiality determinations, EPA is designing the data reporting system to handle

confidential business information that is submitted under the Mandatory GHG Reporting Program.

More discussion of the treatment of Confidential Business Inform ation under subpart A, General Provisions, of part 98 and discus sion of the verification proce ss appears in section II of the preamble for the Mandatory Reporting of Greenhous e Gases; Final Rule ( 74 FR 56260) and the related general provision Comment and Response Documents found in EPA-HQ-OAR-2008-

0508.

For a discussion of the relationship between the reporting required under the Mandatory GHG Reporting Rule and the reporting required by the Toxics Release Inventory, please see the response to comment EPA-HQ-OAR-2008-0508- 0604.1, excerpt 5 in Volume 13 of the Response to Comments Documents prepared for the final Mandatory GHG Reporting Rule published on October 30, 2009. For additional di scussion of the data reporting requirements, please see the response to EPA-HQ-OAR-2008- 0508-0509.1, excerpt 1 in Volume 3 of the Response to Comments Documents for the final Mandatory GHG Re porting Rule. For responses to general comment s on verification, please see th e comment response document volume on Approach to Veri fication and Missing Data.

Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number: 9

Comment: Mexichem considers some of the data that must be submitted to be confidential business information that is beyond the scope of the proposed rule and requests that it be designated as a record that must be maintained in the final rule. Data considered by Mexichem to be confidential business information and beyond the scope of the rule are: the chemical identities of the contents of the streams analy zed under the initial scopin g test, the location and function of the streams that were analyzed unde r the initial scoping test . Mexichem understands that this data needs to be maintained, but questions the need to submit it to the agency. Mexichem requests that this data be deleted from §98.126 and added to records that must be kept under §98.127.

Response: In addition to estimates of their fluor inated GHG emissions and the supporting data that are used to develop emissions estimates, f acilities are required to submit the identity of fluorinated GHG compounds identified during the initial scoping test to confirm which compounds are generated in the production proce ss and potentially emitted. These data help to

128identify fluorinated GHGs that are present and that should be accounted for in the emissions estimates. While industry has i ndicated that facilitie s identify the compounds generated by the production process earlier during la boratory, bench-scale, and p ilot-scale development phases,

there have been instances where facilities have identified additional compounds when they have conducted a species analysis on full-scale pro cesses. (In some cases, these additional compounds may also have been present in the labor atory, bench-scale, or pilot-scale phases, but they were first identified in the full-scale produ ction process because more sensitive tests were applied to the full-scale process.)

EPA is requiring reporting, rather than simply re tention, of these data from the initial scoping test to verify that all poten tially emitted fluorinated GHG are a ppropriately accounted for in the reported fluorinated GHG emissions estimates. Please see the response to comment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16 for more di scussion of the decision to require reporting rather than recordkeep ing for various data elements.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 2

Comment: Furthermore, we continue to be very concerned about the required submission of confidential business information (CBI). The public release of some of the information that is required to be reported under this subpar t jeopardizes our members’ international competitiveness, in that it details how ACC me mber companies manufacture fluorinated GHGs. We urge EPA to release its proposal on handling CBI under the MRR as soon as possible so that ACC member companies may evaluate and ga uge the protectiveness of EPA’s proposed handling procedures before the sensitive information is submitted to the Agency.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 2

Comment: However, furthermore, we continue to be very concerned about the required submission of confidential business information (CB I). The public release of information that is required to be reported under this Subpart, as well as other Subparts of the GHG MRR, jeopardizes our international competitiveness, in that it details how we manufacture fluorinated GHGs. We urge EPA to releas e its proposal on handling CBI under the MRR as soon as possible.

129Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Document Control Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number: 14

Comment: The Confidential Business Information (CB I) protection in the proposed Rule is not broad enough to ensure adequate protection. The data related to manufacturing processes that is demanded for facilities does not appear to be pr otected in the same mann er as other data. It appears that EPA is overreaching to require that so much information be made available to the public. It would be preferable for EPA to keep corporate data confid ential and to release aggregate industry or product category data. Th e current demands for detailed, equipment-based information would open companies to complete disc losure of chemical a nd technical processes. Such revelation that would create significan t CBI exposure to reporting companies is not acceptable and would encourage relo cation of new confidential te chnology facilities outside the US. EPA should not require reports from intern al facility process flows that do not emit.

Response: Please see the responses to comment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16 and comment number EPA-HQ-OAR- 2009-0927-0104, excerpt 9. Even if internal facility process flows do not emit, they may be critical to understanding and verifying emission estimates submitted by facilities. For example, the mass-balance calculation relies on measurement of flows that are not emitted (e .g., the quantities of r eactants, products, and byproducts destroyed).

Commenter: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 3

Comment: Eliminate the reporting requirements for process and business information, which by its very nature represents conf idential business information. Wher e such information is relied upon to develop the annual emissions inventor y, it can be made available for review upon request without compromising the confidential nature.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 17

130Comment: In Section B.ii.2 of the Technical Su pport Document (TSD), EPA provides the Mass Balance approach equations. Equations L-7, L- 10, L-11 and L-12 addres s yield loss and other production process parameters and data that are considered very proprietary by the manufacturer.

Air Products advises that this information on yields, by-products and chemical equations is extremely sensitive, confidential business info rmation (CBI) that is paramount to market competitiveness. Air Products strongly recommends that this data be maintained only at the respective industrial facility a nd only be provided for visual evaluation and validation during onsite inspection. This is currently done with EPA’s Toxics Release Inventory.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 26

Comment: Equations L-7, L-10, L-11 and L-12 address yield loss and other production process parameters and data that are considered very proprietary by the manufacturer. Air Products advises that this information on yields, by-pr oducts and chemical equations is extremely sensitive, confidential bu siness information (CBI) that is para mount to market competitiveness. Air Products strongly recommends th at this data be maintained only at the respective industrial facility and only be provided fo r visual evaluation and valida tion during on-site inspection.

Response: Please see the response to comment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 7

Comment: §98.126(b)(1) and (2). Data reporting re quirements for the mass balance approach require reporting of the data used to calculate absolute and relative uncertainties, as well as the balanced chemical equation that describes the reaction used to manufact ure the fluorinated GHG product. Specifically, the stoichio metric coefficients used in E quation L-7 of subpart L must be reported. Air Products advises th at this information on yiel ds, by-products and chemical equations is extremely sensitive, confidential bus iness information (CBI) that is paramount to market competitiveness. Air Produc ts strongly recommends that this data be maintained only at the respective industrial f acility and only be provided for vi sual evaluation and validation during on-site inspection. This is currently done with EPA’s Toxics Release Inventory.

131Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 38

Comment: Section 98.126 requires reporting of conf idential business information. EPA: Confidential business information is required to be reported annually per §98.126(a), (b), and (c) which includes: chemical content, location and function of process streams, total mass produced of FGHG products, total mass and chemical formula of each reactant, total mass of reactants and products permanently removed from the process, the mass and chemical formula of each byproduct generated. Comment: We recommen d, like EPA’s Toxic Release Reporting Requirements, that only emissions are reported to EPA, confidential business information used to determine the emissions should be kept on-site, a nd available for agency review. This can affect our international and domestic competitiveness— EPA needs to rethink th eir current procedures and requirements.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 32

Comment: As we noted in our June 2009 comments, we are concerned about the types of data that are required to be reporte d under this rule. Much of the re quired data in this subpart are considered confidential business information, and the release of such data to the public could jeopardize the internatio nal competitiveness of ACC member companies. We suggest that only emissions should be reported to EPA, and CBI us ed to calculate the emissions should be kept onsite available for EPA review. This is the practi ce used for CBI data in EPA’s Toxics Release Inventory and we urge EPA to adopt that practice here.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: Dave Stripe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Document Control Number: EPA-HQ-OAR-2009-0927-0067 Comment Excerpt Number: 3

132Comment: As much of the required reporting info rmation is confidential business information, the Alliance supports EPA developi ng appropriate confidential bus iness information protections in the pending part 98 reporting tool.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Section 7.2 Other comments

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 37

Comment: EPA should clarify §98.126(f)(6) to denote that source tests must be submitted within reasonable time of conducting a test. Trigge ring a test report date on a process change is inappropriate. EPA did not provide a clear due date structure fo r testing conducted for reasons other than process changes.

Response: In the final rule, EPA has clarified the required timing and frequency of destruction device performance testing and of reporting of this testing. Specifi cally, facilities that destroy

fluorinated GHGs and that wish to reflect this destruction in their emission estimates must perform destruction efficiency performance tes ting by February 29, 2012. Facilities must repeat the testing every 10 years thereaft er, unless they make a change to the device that would be expected to affect the device’s de struction efficiency. In this case, the facility must re-test the device before the February 28 of the year that immediately follows the change. Facilities must also submit a report by March 31, 2012 (or by Marc h 31 of the year immediately following the year in which they begin destroying fluorinat ed GHGs) that includes the (1) destruction efficiency of each destruction device for each fluorinated GHG whose dest ruction the facility reflects in its emission estimates, (2) the chemical identity of the fluorin ated GHGs used in the performance test, including surr ogates, and information on why the surrogate is sufficient to demonstrate the destruction efficiency for each fl uorinated GHG, (3) the date of the most recent destruction device test, and (4) th e names of all applicable Federal or State regulations that may apply to the destruction process. This report is one-time unless th e facility makes a change to the device that would be expected to affect its destruction efficiency, in which case the facility must submit a revised report by Marc h 31 of the year immediately afte r it makes a change to the

device. EPA believes that these dates allow fac ilities a reasonable amount of time to perform the test and to report the change, while ensuring th at the emissions reported for the year during which the change is made reflect the change.

Note that EPA has not included requirements to submit actual emissions test reports to the Agency under this subpart. However, EPA is requiri ng that facilities retain records of emissions performance testing reports (including revise d reports) for each dest ruction device. The emissions performance testing report must contain all information and data used to derive the destruction efficiency for each fluorinated GHG whose destruction the facility reflects in §98.123, as well as the key process and device conditions during the test.

133Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 38

Comment: Further, EPA should defer to other Clean Air Act authority if the other authority has different test report deadlines. For example, a HWC MACT unit using a CPT process to evaluate FGHG emissions must time its testing schedul e to conform with 40 CFR 63 Subpart EEE. EPA should clarify that any Clean Air Act authority containing a deadline longer than 60 days overrides the 60 day due date when Part 98 testi ng is combined with other EPA required testing. EPA should further require reporter s to explain this situation in any test report where conflicting test report deadlines may occur.

Response: EPA has revised the destruction efficiency testing frequency to once every 10 years, instead of once every five years as proposed. Facilities may use previous destruction device testing (including testing carried out under certain other Clean Air Act regulations) that meets the requirements in §98.124(g). Because many other rule s require testing on a 5-year frequency, , a facility that conducts testing at 5-year intervals should also be able to demonstrate compliance with the 10-year frequency in subpart L. (Under 40 CFR 63, subpart EEE for Hazardous Waste Combustors, certain hazardous waste combustors that feed waste to the flame zone are required to conduct a DRE test once; for those combustors, the most recent DRE testing may be used to satisfy subpart L if no design, operation, or main tenance changes or modifications have been

made since that test that would a ffect the destruction efficiency.) However, if a facility destroys

PFCs or SF 6 and wishes to reflect this destruction in its emission calculations, and if it has not previously tested the destruction device with th ese compounds, then the facility will need to perform this testing before refl ecting destruction of PFCs or SF 6 in its calculations. As discussed in the preamble of the final rule, PFCs and SF 6 compounds are substantially more thermally stable than most class 1 POHCs, and therefore the destruction e fficiencies determined for these class 1 POHCs will not be applicable to PFCs or SF 6 . Also, if a facility makes a change to the device that would be expected to affect the device’s destructi on efficiency, the facility must submit a revised report by March 31 of the year immediat ely following the change.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 4

Comment: EPA requires fluorochemical marketers to report basic mass balance information for fluorinated greenhouse gas (“FGHG”) producti on at §98.416(a)(8) and (a)(9) of Subpart OO. Upon final Subpart L promulgation, these Subpa rt OO provisions become redundant. Subpart L facilities will be repo rting the same process throughput da ta per either proposed §98.126(b)(3) and (b)(5) or §98.126(c)(1). Reporting the same da ta in two reports, one with quality assured data (Subpart L) and one with estimated data no t subject to quality assu rance provisions (Subpart

134OO) invites unnecessary comparisons between data sets of differing quality. Requiring production data to be reported in one place mi nimizes the confidential business information (“CBI”) concerns discussed below. EPA should de fer to the quality assu red Subpart L provisions in a new §98.126(h) that notes that compliance with §98.126 th roughput reporting requirements satisfies §98.416(a)(8) and (a)(9) reporting obligations. Were EP A to determine that all reporters required to document production throughput in Su bpart OO will be required to comply with Subpart L, then EPA should delete and reserve §98.416(a )(8) and (a)(9).

Response: Although EPA did not open subpart OO to comment through this rulemaking, we note that the reporting requirements at §98.146(a)(8 ) and (9) (mass of reactants fed into the process and mass of reactants, byproducts, and other wastes permanently removed from the process) are not necessarily redundant with those in subpart L. While these data elements are required to be reported for the mass balance appro ach in subpart L, only one of them (reactants)

could be reported under the emission factor or em ission calculation factor approach, and only if it is used as the process activ ity data in the emissions calculation. While the commenter expresses concern that there ar e different quality assurance pr ovisions between subpart L and subpart OO, nothing prevents facilities from re porting the more quality-assured quantity under both subparts; in fact, if facilities use the ma ss-balance approach under subpart L, they must report the same fluorinated GHG production fo r the process under subpart OO.

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Comment Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number: 10

Comment: EPA Should Further Clarify The Interpla y between Subpart L and Subpart OO. The Alliance appreciates EPA's efforts to integrate Subpart L and the 2009 Subpart OO to minimize reporting overlap. Subpart OO regulates fluorinat ed greenhouse gases in commerce, including sales, imports and exports, and destruc tion of fluorinated greenhouse gas products.

Both the proposed Subpart L and the final Subpart OO require fluor inated greenhouse gas production reporting. EPA should develop a method to consolidate produc tion reporting between the two Subparts is. As much of the required production reporting information is business confidential, the Alliance supports EPA deve loping appropriate confidential business information protections in the pending Part 98 reporting tool.

Response : EPA recognizes the potential overlap betw een the reporting under subpart L and that under subpart OO. In general, subpart OO is focused on production, transformation, and destruction of fluorinated GHGs and subpart L is focused on emissions of fluorinated GHGs from production facilities. However, some data are required to be reported under both subparts. This data falls into two categories. First, in some cases, the primary data being reported under one subpart (e.g., fluorinated GHG production under subpart OO) is also required to be reported under the other to aid in data verification (e.g., production under subpart L, which may be used in the subpart L emissions calculations and would be expected to be correlated with emissions generally.) Second, some of the emissions re ported under subpart L are of fluorinated GHGs

135whose production is also reported under subpart OO. This category includes emissions from venting or destruction of fluorin ated GHGs that are returned to the facility from the field, and

emissions from transformation of fluorinated GHGs that are produ ced at other facilities.

For the first type of overlapping data, EPA w ill consider whether and how the data reporting process could be streamlined. For the s econd type of overlapping data, EPA is requiring separate reporting of emissions that were (or ma y have been) counted previously as additions to the fluorinated GHG supply. This is to ensure that they are not double-counted as both supply

and emissions.

For more discussion of confidential business info rmation determinations and treatment, please see the response to comment nu mber EPA-HQ-OAR-2009-0927-0092.1, excerpt 2.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 3

Comment: Because Subparts L and OO require re porting of different aspects of the fluorochemicals industry, some provisions of these subparts addre ss similar reporting requirements. For example, proposed §§98.122(c)(1), (c)(2), and (c)(3) of Subpart L require reporters to provide EPA the same data as §§98.416(a)(1), (a)(2), and (a)(3) of Subpart OO. Both sets of provisions require re porting of production, transformation, and destruction of FGHG products. Because Subpart OO is primarily concerned with FGHG entry into commerce, EPA should rely on Subpart OO throughput reporting instead of duplicating throughput reporting requirements in Subpart L. Proposed §98.122(c) is redundant with existing §98.416(a) for Subpart OO reporters also repor ting under Subpart L. EPA should note in the main part of §98.122(c) that reporting thr oughput parameters under the ex isting Subpart OO provisions satisfies §98.122(c) requirements. EPA should harm onize these two subparts as much as possible instead of imposing double repor ting on the regulated community.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 4, and please see the response comment number EPA-HQ-OAR-2009-0927-0117.1, excerpt 10.

Commenter Name: Dave Stripe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Comment Number: EPA-HQ-OAR-2009-0927-0067 Comment Excerpt Number : 2

Comment : The Alliance appreciates EPA’s efforts to integrate Subpart L and last year’s Subpart OO to minimize overlap. Both the proposed Subpart L and the fi nal Subpart OO require fluorinated greenhouse gas repor ting. EPA should develop a me thod to consolidate production reporting between the two subparts.

136Response : Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 4, and please see the response comment number EPA-HQ-OAR-2009-0927-0117.1, excerpt 10.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 5

Comment: EPA should also harmonize proposed §98.124(g) and §98.416(a)(3) requirements to

document the amount of FGHG ente ring the facility for destructi on. EPA should clarify that the inbound FGHG reporting in Subpart OO meets the Subpart L reporting requirement.

As EPA considers finalizing reporting requireme nts for recovered refrigerants subject to disposal, the Agency should carefully consider if such regulation woul d discourage responsible refrigerant management practices. EPA shoul d not proscribe reporti ng obligations that discourage end users or refrigerant servicing entities from proper re covery, reuse, or disposal of refrigerants.

Response: EPA has revised §98.124(h) in the final rule (formerly §98.124(g ) at re-proposal) and made slight revisions to §98.414(h) to in crease the consistenc y between these two provisions. (Paragraph 98.414(h) is the monitori ng provision in subpart OO that corresponds to §98.124(h) in subpart L, and whose results ar e reported under §98.416(a)(3) in subpart OO.)

One difference remains: where the fluorinated GHG is not the only material included in the

mass fed into the destruction devi ce (e.g., contained in returned cy linders), the concentration of

the fluorinated GHGs in the mass fed into the destruction device must be measured under §98.124(h) while it need only be estimated under §98.414(h) .

EPA has concluded that such measurement is important for purposes of subpart L because fluorinated GHGs bound for disposal are generally being disposed of becau se they are no longer

pure, 1 and the efficiency with which fluorinated GHGs are destroyed (DE) varies depending on the identity of the fluorinated GHGs. Thus, if a returned cylinder is believed to contain SF 6 , but it actually contains SF 6 mixed with CF 4 , which is more difficult to destroy, the extent and the

nature of the emissions from the destruction will be not be calculated or reported correctly unless the contents of the cylinder are analyzed.

The commenter implies that a requirement to meas ure the concentrations of fluorinated GHGs in

the mass fed into the destruction device could disc ourage proper recovery, reuse, or disposal of refrigerants, but the commenter does not provide any rationale to support this concern. EPA does not believe that the measurement requir ement will discourage proper handling of refrigerants. First, fluorinated GHGs, including refrigerants, th at are being destroyed are not

1 This may be because they have br oken down under hot or energetic cond itions (e.g., compressor burnouts for refrigerants or excessive arcing for SF 6 ) or because they have b een accidentally mixed with other fluorinated GHGs (e.g., two different refrigerants).

137being recycled. Thus requirements to analyze destroyed fluorinated GHGs cannot interfere with recycling. Second, facilities would be expected to analyze the contents of materials returned to their sites for recycling or destruction in the ordi nary course of business. This is because such analysis is necessary to verify that the material s may be safely recycled or fed into destruction

devices.

To minimize inconsistent monitoring and reporting between §98.414(h) and §98.124(h), facilities may report under §98.416(a )(3) the quantity fed into the destruction device that is monitored under §98.124(h).

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 40

Comment: As much of Subpart L forces tec hnology, Arkema assumes that, over the next several years, the calculation pr ocedures, testing methods, and m onitoring capabilities available to reporters will improve. When reporters evalua te these improvements, a reporting entity may find opportunities to amend prior reports with improved actual FGHG emissions data. So far, EPA has not included any Part 98 update provisions in the seve ral climate change reporting rulemaking packages that have been proposed. EPA should amend the Part 98 Subpart A general provisions to allow reporters to update actual FGHG emissions da ta, in a manner similar to how Toxic Release Inventory (“TRI”) reporting entities may update ac tual TRI release reports for prior years. This update capabi lity should extend for either thr ee or five years after report submittal. EPA should encourage best availabl e actual FGHG emissions data by providing a reasonable report update mechanism.

Response: The Mandatory GHG Reporting Rule already includes a mechanism at §98.3(h) to revise an annual report in the event that the facilit y or EPA discovers an erro r in the in the report. However, EPA is not finalizing a provision at this time to allow facilities to update their reports based on improved data or methods. While EPA agrees that it may be desirable to update emissions estimates for previous years based on improved data or methods, such updates must be undertaken carefully, ensu ring that the improved methods or da ta are properly applied to past activities. Otherwise, inappropria te application of revised data or methods to past activities may misrepresent both the past emissions and the emissi ons trend over time. In the future, EPA plans to consider whether it is appr opriate to include a provision for recalculating previous emissions based on improved data or methods under the Greenhouse Gas Reporting Program, and if so, how such a resubmission process should be impl emented. If the Agency concludes that updates should be allowed, EPA will initiate a rulemaking to adopt update provisions in subpart A.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 50

138Comment: Proposed §98.127(b)(9) requires reporters to document when FGHG process vent emissions are controlled. The propos al states that facili ties are to keep reco rds relating to the dates and times emissions from FGHG “campaign[ s] or batch[es].” EPA should clarify if “campaign” is meant to include continuous proce ss activities. Arkema views campaigns as shortterm production activities not t ypically associated with long-term production from baseload continuous production units that do not cha nge production characte ristics over time.

Existing Title V obligations under 40 CFR 70 and permitting authority Title V regulations mandate that reporting facilities document when emissions are not properly routed to an emission control device. EPA should require re porters to document when FGHG emissions bypass expected emission controls.

Documentation of non-control fits existing Clean Air Act reporting obligations. This proposal requires reporters to maintain mirror image records, one set for when the system operates properly, one for when the system is in bypass. Such double recordkeeping invites inconsistency and inaccuracy.

Response: EPA has added an alternative to §98.127(b)(6) (forme rly §98.127(b)(9) in reproposal) to allow facilities to record the da tes and time periods when process vents bypass the destruction device. Adding the a lternative allows fac ilities to choose whethe r they will record vented periods or bypass periods. EPA has re moved the terms campaign and batch since these terms were confusing to commenters, and has instead simply referred to time periods during which the process was operating.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 51

Comment: In addition, many reporters operate units under air permits that allow for a limited amount of bypass time. Many reporters may elect to document this authority as an alternate operating scenario, instead of as a bypass unde r §98.127(b)(9). EPA should clarify that only those bypass events not managed under the altern ate operating scenario authority elsewhere in Subpart L must be repo rted at §98.127(b)(9).

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 50 and excerpt 52.

Commenter Name: Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 4

139Comment: Reduce the reporting burden associated with supporting information. In an effort to create an assurance of accuracy, the agency has set reporting requirements for an exhausting

level of information. Where such information is relied upon support emissions calculations, it can be made available upon request.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 40

Comment: Section 98.126(a)(1) and (2) inappropriatel y requires annual re porting of the initial scoping study. EPA: Section 98.126 (a) states: “A ll facilities: In additio n to the information required by §98.3(c), you shall report the following information: (1 ) The chemical identities of the contents of the stream(s) (including proces s, emissions, and destroyed streams) analyzed under the initial scoping measurement of fl uorinated GHG at §98.124(a)...” Comment: §98.124(a) stipulates a one-time initial scop ing study. Since the scoping study will contain business confidential information (CBI), and creates unnecessary administrative burden to submit annually, it is recommended to be kept on site for agency inspection and review, but not reported to the agency initially or annually.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0106.1, excerpt 16 and see the response to commen t number EPA-HQ-OAR-2009-0927-0104, excerpt 9.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 33

Comment: Section 98.126(a)(3) incorre ctly requires annual emi ssions reporting for equipment

leaks. Facilities that calcul ate fluorinated GHG emissions using the mass balance method are not required to monitor for equipment leaks, and therefore should not have to report them.

Response: EPA has clarified in the promulgated rule th at only those facilities that are using the site-specific process-vent-specifi c emission factor or emission cal culation factor are required to report the method used to estimate em issions from equipment leaks.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 39

140Comment: Section 98.126(a)(3) incorre ctly requires annual emi ssions reporting for equipment leaks. EPA: Section 98.126( a)(3) states: “The annual emi ssions of each fluorinated GHG by process, for equipment leaks, and for the facility as a whole.” Comment: Facilities that calculate FGHG emissions by the mass balance option are not required to monitor for equipment leaks, and therefore should not report them.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 33.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 34

Comment: Section 98.126(e) requires reporting of monitoring re sults for deviations from monitoring limits set during the emissions test. “D eviation” is a defined term for the Part 71 air permit program and means failure to meet an emission limitation/ requirement (40 CFR 71.6(a)(3)( iii)). This is not the intent, nor should it be, for emission estimation required for this rule. We recommend the following wording for § 98.126(e): (e) Reporting of destruction device monitoring data. A fluorinated GHG production faci lity that destroys fluorinated GHGs shall report excess emissions that resu lt from malfunctions of the dest ruction device or associated equipment. Such excess emissions would occur if the destruction efficiency was reduced due to

the malfunction.

Response: EPA agrees with the commenter and the term “deviation” has been removed from §98.126(e) in the promulgated rule. §98.126(e) has been updated to focus on reporting of the

emissions that occur due to malf unctions of the destruction device. Use of the term “deviation” has also been removed from §98.124(i) (for merly §98.124(h) at re-proposal), and the requirements here focus on accounting for reduced destruction efficiency during any periods when operating outside of permitted or manuf acturer specified operating conditions for the

device.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 41

Comment: Alternate wording recommended for Sect ion 98.126(e). EPA: §98.126(e) requires reporting of monitoring results for deviations fr om monitoring limits set during the emissions

test. Comment: Deviation is a defined term fo r the Part 71 air permit program and means failure to meet an emission limitation/requirement per 40C FR 71.6(a)(3)( iii). This is not the intent, nor should it be, for emission estimation required fo r this rule. DuPont recommends the following wording; “(e) Reporting of de struction device monitoring data. A fluorinated GHG production

141facility that destroys fluorinated GHGs sha ll report excess emissions that result from malfunctions of the destruction device or associated equipment. Such excess emissions would occur if the destruction efficiency was reduced due to the malfunction.”

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0092.1, excerpt 34.

Section 8 Records that Must be maintained

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 44

Comment: Proposed §98.127(b)(7) requires reporters to identify “whether the process was representative or whether it was another operating scenario.” We believe that EPA is requesting reporters to document operating scenario change s over time and times where operations were not representative of the §98.124 basis. EPA should clarify this language, and include provisions documenting new operating scenarios and process changes that do not constitute new operating

scenarios.

Response: The EPA agrees that the language in propos ed §98.127(b)(7) could be more clear. As part of the effort to clarify and stream-line th e use of the term operati ng scenario throughout the rule, this paragraph §98.127(b )(7) was deleted from the prom ulgated rule, as it was not necessary. See section 4.3 of this RTC document for discussion of changes to the rule related to the concept of an operating scenario.

Section 9 No Comments

Section 10 Other subpart 1 comments

Section 10.1 Definitions

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 1

Comment: The FGHG definition vapor pressure thresh old of 1mm Hg needs to be increased. EPA: Applicability for Subchapter L reporti ng is based on the definition of Fluorinated Greenhouse Gas (FGHG) in Subpart A: “Fl uorinated Greenhouse Gas means ...and any fluorocarbon except for controlle d substances as defined at 40CFR part 82, subpart A and substances with vapor pressures of less than 1 mm hg absolute at 25 degrees C....” Comment: A vapor pressure of 1 mm Hg encompasses produc ts that are considered non-volatile with small air emission potential. EPA developed the defi nitions of heavy liqui d and light liquid to appropriately focus Hazardous Air Pollutant re gulations on process streams with sufficient

142emission potential to justify th e cost of routine measurement. 40 CFR 63 subpart H (40 CFR 63.161) defines light liquid with vapor pressure of the regulated constituents at greater than 0.3 kilopascals at 20°C (approximate ly 2.2 mm Hg). For example, one of our large sites that monitors over 10,000 components for a wide ra nge of HAPs and VOCs has not found a leaking component in the last 2 years for a chemical with a vapor pressure less than 15 mm Hg. Application of the light liquid vapor pressure threshold to th e FGHG definition would more appropriately exclude heavy fluorochemical, fl uoromonomer, and fluoropolymer liquids with minimal potential to emit.

Response: Under this rulemaking, EPA did not ope n the definition of fluorinated GHG for comment. However, EPA has revised the propose d leak monitoring provisions to address the commenter’s observation that heavy (i.e., low vapor pressure) liquids rarely leak. Specifically, we have clarified that equipment in heavy liquid service may be excluded from monitoring, although facilities are re quired to estimate emissions from this equipment using another approach. For example, they could use either de fault emission factors or a site-specific method based on the frequency and severity of leaks obs erved through visual, au ditory, or olfactory inspection. We have added a de finition for “in heavy liquid service” as well as a complementary definition for “in light liquid serv ice.” Th latter definition define s “in light liquid service” to mean a piece of equipment in regulated material service that contains a liquid that meets the following conditions: (1) The vapor pressure of one or more of the compounds is greater than 0.3 kilopascals [2.25 mm Hg] at 20°C, (2) The total concentration of the pure compounds constituents having a vapor pressu re greater than 0.3 kilopascals at 20°C is equal to or greater than 20 percent by weight of the total process stream, and (3) The fluid is a liquid at operating

conditions.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 2

Comment: The definition of Research & Developmen t needs to be modified to include pilot plants that do not sell commercial product to make a profit. EPA: In the Response to comment on subpart OO, EPA describes an exemption for R&D operations as follows: “Therefore, the

final rule defines R&D as activities conducted in process units or at laboratory bench scale settings whose purpose is to conduct R&D for ne w processes, technologies, or products, and whose purpose is not for the manufacture of pr oducts for commercial sale, except in a de minimis manner. Comment: Pilot plants are a n ecessary part of efforts to develop new products

in the transition from the laborat ory to eventual actual commerci al production. These pilot plants may also send product to potential customers fo r evaluation and their own product development. Sometimes, the potential customer may be charge d, but the revenue is to help defray the development costs rather than for profit making for a business. Suggested change: “Research and development means those activ ities conducted in pro cess units, pilot plants or at laboratory bench-scale settings whose purpos e is to conduct research and de velopment for new processes, technologies, or products and whose purpose is not for the manufacture of products for commercial sale, except in a de minimis manner.”

143Response: Under this rulemaking, EPA did not open th e definition of research and development for comment. However, discussion of this issue may be found in the final Mandatory GHG Reporting rule at 74 FR 56285 (October 30, 2009 ) and in response to comments document Mandatory Greenhouse Gas Reporting Rule: EPA's Response to Public Comments, Volume No. 12, Subpart A: Applicability and Reporting Schedule.

Commenter Name : Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number: 1

Comment: The term “by-product” needs to be clearly defined in the final rule and the definition should clearly indicate that by-pr oducts in trace concentrations , as defined in §98.6, should not

be included in emission calculations. The bala nced chemical equation for the manufacture of HFC-134a at Mexichem’s facility is: 4HF + TCE → R134a + 3HCl, where: HF is hydrogen fluoride, TCE is trichloroethylene, and HCl is hydrogen chloride.

Mexichem has always considered HCl to be the only by-product of the production process. Impurities are produced in our process in ppm con centrations. Neither the proposed rule nor the definitions provided under the existing §98.6 provide a definition for “by-product.” The Technical Support Document (Updated) for Emissions from Production of Fluorinated Gases (March 22, 2010) provides in section 1.B., that “many reactions producing fluorinated GHGs, CFCs, and HCFCs also generate significant quan tities of chemically re lated by-products, e.g., through over-fluorination or side reactions.” HFC-143a is shown in the document to be a byproduct of HFC-134a production. Mexichem considers HFC-143a to be one of the impurities in its production process. Therefore, without a clear definition, it is not obvious whether impurities produced in our process should be considered by-products.

The definitions for terms used in equations L-11 and L-12 of the proposed rule indicate that if the concentration of the by-product k is only a tr ace concentration, then the concentration to be used in the equation is zer o. In order to avoid misunderstanding, the fact that trace concentrations of by-products should be disregar ded for the purposes of calculating emissions should be clearly stated in a definition, or elsewhere, in the final rule.

Response: A definition for trace concentration is in cluded in subpart A of part 98. EPA has added a definition for by-product to the promul gated rule as follows: “By-product means a chemical that is produced coincidentally duri ng the production of another chemical.” This means that each compound produced that is not th e intended primary product is considered a byproduct. In the example provided by the comm enter, both the HCl and HFC-143a would be considered by-products if produced during the production process, although the HCl would not be considered a fluorinated GHG by-product; howe ver, if the HFC-143a were present in a raw material or other input to the pr ocess and were not “pr oduced” as a direct re sult of the production process, it would not be considered a by-product. (Nevertheless, it would need to be tracked if it occurred in destroyed or emitted streams in gr eater than trace concentrations.) As the

144commenter notes, if the by-product were present in a stream in trace conc entrations, then the facility would not be required to monitor and track the quantity, i.e., could assume the

concentration is zero. Rather than include th e exemption for trace concentration in the byproduct definition, EPA has included the text that excludes trace concen trations of compounds from the monitoring and calculation requirements in the appropriate places throughout the rule.

Commenter Name : Brian R. Keck

Commenter Affiliation: Air Products and Chemicals, Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 13

Comment: Further, Air Products recommends that EPA exempt constituents with concentration levels from estimation, measur ement, sampling, monitoring, QA/QC, reporting, recordkeeping and other requirements of subpart L as it applies to fluorinated gas production including processes, process vents and equipmen t leaks. Similar to the definition of “trace constitution” in §98.6 of the final MRR, fluor inated GHG product constituents present at concentrations below 0.1 percent by mass should be exempted from the rule’s requirements.

Response: A definition for trace concentration is al ready included in subpart A of part 98. “Trace concentration” is defined as any concen tration “below 0.1 percent by mass of the process stream.” EPA has explicitly exempted trace c oncentrations from the monitoring and calculation requirements for the initial scoping test, and for the mass balance, emission factor, and emission calculation factor approaches. Because trace co ncentrations are exempted from the monitoring and calculation requirements for these approaches, they are also implicitly exempted from the reporting and recordkeeping requirements for these approaches.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number : 9

Comment : ACC believes that EPA should exempt cons tituents with de minimis concentration levels from estimation, measurement, sampli ng, monitoring, QA/QC, repo rting, recordkeeping and other requirements of subpart L as it appl ies to fluorinated ga s production including processes, process vents and equipment leaks. Us ing the definition of “t race concentration ” in §98.6 of the final MRR, we believe fluorinated G HG constituents present in a process stream at concentrations below 0.1 percent by mass should be exempted from the rule’s requirements.

Response : Please see the response to co mment EPA-HQ-OAR-2009-0927-0106.1, excerpt 13

for a discussion of the rule’s trea tment of trace concentrations.

145Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 16

Comment: EPA should adopt a low-concentration fl oor below which reporters do not need to document FGHG content of process streams. Several process streams in fluorochemical manufacturing process units may contain a triv ial amount of FGHG, cau sing trivial amounts of FGHG emissions. At §98.416(c) and (d) of S ubpart OO, EPA defines a floor below which FGHG reporting is not required. EPA should adop t a similar guideline, based on Subpart OO conditions in effect when Subpa rt L reporting begins, allowing re porters to not document process streams containing less than the Subpart OO mass concentration threshold in effect when Subpart L reporting begins. Arkema expects to id entify several process streams, including coproduct hydrochloric acid, containing minimal F GHG concentrations that will not significantly impact actual FGHG process emissions. This minimum FGHG concentration threshold will allow reporters to concentrate on documenting F GHG contents of streams that could potentially impact actual FGHG emissions.

Response: Please see response to comment number EPA-HQ- OAR-2009-0927-0106.1, excerpt 13.

Commenter Name : John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 27

Comment: The §98.124(a) concentration exemption is not clearly stated. EPA: Page 18674 of the preamble indicates the scoping study is for compounds present above 0.1%. The 0.1% exemption for the scoping study in the actual rule language was not evident. Comment: The rule’s applicability section ( 98.122 (c)) should clarify a “trac e” compound exemption. With the current definition of trace being 0.1%, lo w volume products (i.e., 11 tons/yr specialty fluoromonomers) with a 0.1% FGHG impurity e quates to a small potential FGHG effect, particularly since many fluoromonomers have lo w vapor pressure, short atmospheric lifetimes,

and less than 50 calculated GWP. A mass base d, or calculated GWP exemption for low volume products’ FGHG impurities would significantly reduce the rule’s burden on low volume specialty chemical manufactur ing involving insignificant CO 2 e emission potential. Proposed rule changes and additions;

“§98.438. Definitions. CO 2 e mass de minimus emissions – process vent CO 2 e emissions of a compound less than 100 mt/yr. Use GWPs as listed on Table A-1 of subpart A, or if the compound is not listed, by alternate methodologies.

§98.122 GHGs to Report. (c) You must report th e total mass of each fluorinated GHG (excluding trace constituents or compounds with CO 2e mass de minimis emissions) from:...”

146Response: Please see the response to co mment EPA-HQ-OAR-2009-0927-0106.1, excerpt 13

for a discussion of the rule’s trea tment of trace concentrations.

EPA agrees that the rule text s hould be revised to include the trace concentration exclusion under the initial scoping test in §98.124(a) . This language was inadverten tly left out of the April 2010 proposal and has been included in the final rule.

No de minimis definition for CO 2 equivalent mass has been added to the rule. However, the rule includes provisions to reduce the burden of estimating emissions from low-emitting vents and processes under both the process- vent-specific emission factor approach and the mass-balance approach. Please see the discussi on of process vent cutoffs under section 4.3 of this Response to

Comment document.

Commenter Name : Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 35

Comment: A new definition for lo w-concentration constituen t should be added to the definitions under this subpart similar to the de finition of “trace concen tration” in §98.6, i.e., a fluorinated GHG constituent in a process stream that is present in concentrations below 0.1 percent by mass.

Response: Please see the response to co mment EPA-HQ-OAR-2009-0927-0106.1, excerpt 13

for a discussion of the rule’s treatment of trace c oncentrations. EPA believes that the term “trace concentration” is adequate to address the commenter’s concerns; a second term for the same concept is not necessary in the context of subpart L.

Section 10.2 Effective dates

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 55

Comment: Arkema is concerned that the proposed one-year Subpart L implementation schedule may be impossible to meet. Subpart L is likely th e most complex Part 98 subpart to implement. Many of the proposed Subpart L monitoring, te sting, and reporting requirements involve reporting facilities expending subs tantial engineering resources to evaluate issues of first impression. Never before has the fluorochemi cal industry researched FGHG emissions from manufacturing operations to this level of detail.

Proposed §98.124(m) allows reporters to petition EP A for up to a year to utilize best available monitoring methods (“BAMM”) during implem entation. In contrast, proposed §98.124(j) requires reporters to complete the scoping te sts, emissions testi ng, and emission factor

147development, as described above, before the e nd of 2011. Arkema interprets these two provisions as conflicting, with the December 31, 2011 lang uage at proposed §98.124(j) obviating the §98.124(m) BAMM provisions. Were one year ade quate to complete the scoping study, the testing protocols, and LDAR program implemen tation, Arkema would request that EPA strike §98.124(m) and note in §98.124(j) that presumptiv e BAMM provides the entire 2011 calendar year to develop compliant reporting methods. However, several factors could combine to compromise our ability to complete implementati on within one year. First, the required fugitive monitoring would approximately double the exis ting Arkema Calvert City, Kentucky LDAR program. Arkema currently manages the Calvert C ity LDAR system in-house, and is considering hiring an additional LDAR technician (or transf erring another employee into an LDAR role). Before conducting FGHG LDAR monito ring, the facility will need to identify each component in

FGHG service. To be consistent with the exis ting Arkema Calvert City facility LDAR program, the facility would likely “tag” each component system and register each tag, and subcomponents of each tag, into the facility LDAR database program. Arkema estimates that this process, plus the training of new LDAR technician staff, will take an entire year or mo re, after publication of a final Subpart L, to complete. If any extern alities arise to dela y LDAR implementation, compliance with §98.124(j) is at risk. Second, a limited number of source testing companies possess the requisite equipment and skill to comp lete FGHG testing. In our experience, most stack testers cannot identify the range of FGHG molecules that must be measured for Subpart L. These same test firms will be conducting confirmatory comprehensive performance test (“CPT”) evaluations of all regulated hazardous waste in cinerators per 40 CFR 63.1207(d)(2) in late 2010 and early 2011. Arkema will not be able to fu lly assess the Subpart L implementation schedule until after completing the scoping tests for all of the potential FGHG emission points.

Response: To clarify the measurement schedule , EPA proposed to a llow facilities until December 31, 2011 to complete initial scoping and emissions tests and to develop emission factors. There was no requirement to use or apply for BAMM to conduct emission factor measurements (e.g., stack testing) according to this schedule. Th is is because emission factors can be applied to 2011 activity data at any ti me until the reports are due to estimate 2011 emissions from each process. In the final ru le, EPA is allowing facilities until February 29, 2012 to develop emission factors. This will provide facilities an additional two months to develop

emission factors but will still allow facilities to report 2011 emissions using those emission factors. Again, facilities do not need to use or apply for BAMM to conduct emission factor testing according to this schedule.

In addition to giving facilities more time to complete scoping measurements and develop emission factors, we have made multiple changes to the technical requirements of the rule that we expect will make it more practicable for facili ties to complete testing and other measurements by the deadlines specified in the rule. With respect to the initial scoping test, we have limited the scoping test requirement to pro cesses that would emit more than one metric ton per year of fluorinated GHGs from any single vent before the imposition of control technologies, to avoid the need to survey a large number of processes with relatively small fluorinated GHG emissions. (Please see section 5.1 of this response to comm ents document for discussion of changes to the initial scoping test.) With respect to emissions f actor testing, the process vent threshold has been adjusted to account for the destru ction efficiency of controls a nd to permit use of a default GWP of 2,000 for fluorinated GHGs that do not have GWPs listed in Table A-1. (Please see the

148preamble to the final rule and section 4.3 of this response to comments document for discussion of changes to the process vent th reshold.) With these changes to the process vent threshold, we anticipate that fewer process vents will have to be tested, and facilities will be allowed to develop emission calculation factors for a greater number of process vents. Another change to the technical requirements is that emissions factor testing is not required for batch processes, and facilities may develop emission calculation factors fo r these process vents. Use of calculations for determining emissions from batch process vents is consistent with requirements for batch process vents in other rules (for example, 40 CFR 63, subpart GGG and 40 CFR 63, subpart FFFF). (Please see section 4.3 for discussion of cha nges to the batch proce ss vent requirements.) With respect to analysis of fluorinated GHGs th at occur in process and vent streams, EPA is allowing facilities to use alternative analytical procedures to identify fluorinated GHGs and to quantify their concentrations. (Please see the prea mble to the final rule for more discussion of alternative analytical methods and the requirements surrounding their use.) Finally, EPA is allowing the use of alternative monitoring appr oaches to monitoring of equipment leaks for fluorinated GHG in the promulgated rule. (Pl ease see section II.E, Fluorinated Gas Production (Subpart L) of the preamble to this rule for discussion of equipment leak monitoring alternatives.)

To alleviate any remaining undue hardship on the industry, EPA has included additional flexibility in the subpart L BAMM provisions. Th ese provisions are intended, for example, to minimize unplanned shutdowns and to accommodate multiple facilities trying to simultaneously obtain measurement services from a relatively lim ited pool of vendors. Please see the preamble to the final rule for a detailed discussion of the BAMM provisions and how they would apply to

the different emission estimation methods a nd parameters; a brief overview of the BAMM timelines is provided below.

In the final rule, facilities may use BAMM to estimate emissions that occur through June 30, 2011 without submitting a request to EPA. (Note th at this initial BAMM doe s not affect the due date for completion of scoping measurements, em ission factors, and emission characterizations, which is February 29, 2012. However, it does aff ect the date by which, for example, flow meters meeting specific accuracy and precision requirement s must be acquired, installed and operated.)

To use BAMM to estimate emissions that oc cur beyond June 30, 2011, facilities must submit a petition and EPA must approve it. The due da tes for the petition and for the completion of measurements depend on the type of measurement being conducted.

Facilities wishing to use BAMM to estimat e emissions that occur throughout 2011 for parameters other than scoping speciation, emission factors, and emission characterizations must submit a request to EPA by February 28, 2011. If th e petition is granted, th ese facilities must begin operating the required monitoring equipment by January 1, 2012. Facilities wishing to use BAMM to estimate emissions that occur throughout 2011 for scoping speciation, emission factors, and emission characteri zations must submit a petition to EPA by June 30, 2011. If the petition is granted, these facili ties must complete necessary m easurements by February 28, 2013. EPA is also reserving the right to approve use of BAMM to estimate emissions that occur after 2011 under unique and extreme circumstances which include safety, techni cal infeasibility, or inconsistency with ot her local, State or Fe deral regulations.

149By allowing more time to complete measurem ents (even without BAMM), allowing additional flexibility in the methods that may be used to characterize and estimate emissions, and allowing extension of the use BAMM under limited circumstances, we believe that we have made appropriate accommodations for the challenges faced by the facilities subj ect to subpart L in estimating their fluorinated GHG emissions while en suring that estimates are reasonably timely, accurate, and precise.

Commenter Name : Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number: 6

Comment: Comment #5: Allow the use of Best Available Monitoring Methods (BAMM) under §98.3(d)(1) through (3) through the end of calenda r year 2012. Mexichem initially understood §98.124(m) to mean that BAMM could be used for the entire calendar year 2011. However, during a telephone call with EPA staff, Mexich em learned that, as proposed BAMM would only

be able to be used for the fi rst three months of cal endar year 2011. However, it would not apply to the initial scoping study, emissions testing, etc. requi red under §98.124. Mexichem is requesting that the use of BAMM be allo wed through the end of calendar year 2012. Mexichem’s preference is to use the mass balance approach for estimating its emissions. In the event that Mexichem needs to upgrade measurement and/or monitoring equipment in order to achieve the error criteria of §98.123( a) (if the agency retains the requirement to calculate these errors) it will likely need a plant shutdown to install such equipment. Currently, our next scheduled plant shutdown is during the fourth qua rter of 2012. Requiring us to meet the error criteria after March 31, 2011 would cause undue fina ncial hardship and upse t to our business in

the form of unscheduled shutdowns or unplanned capital expenditures.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name: Joel R. Hall

Commenter Affiliation: Mexichem Fluor Inc.

Comment Number: EPA-HQ-OAR-2009-0927-0104 Comment Excerpt Number : 7

Comment: Does §98.124(m) negate the need to meet the error criteria of §98.123(a)? §98.124(m) states that for calendar year 2011 mo nitoring, you may follow the provisions of §98.3(d)(1) through (3) for best available monitori ng methods rather than follow the monitoring requirements of this section. §98.124(b) states that if you use the mass balance method, you must conduct monthly mass measurements .... that allo w the facility to meet the error criteria in §98.123(a). It can be inferred that §98.124(m) allows the use of monitoring methods that do not meet the error criteria in §98.123(a). This should be clarified in the final rule.

150Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55. Please see section II.E. 3 of the preamble to this rule for a response to the comments regarding BAMM provisions as they appl y to the mass-balance approach.

Commenter Name: Dave Stirpe

Commenter Affiliation: Alliance for Responsible Atmospheric Policy

Document Control Number: EPA-HQ-OAR-2009-0927-0117.1 Comment Excerpt Number: 13

Comment: The Alliance also appreciates EPA allowing best available monitoring methods for the entire 2011 calendar year. It appears that EPA appreciates the larg e amount of preparation, monitoring, and recordkeep ing that each reportin g facility must establish to comply with proposed Subpart L. However, we are concerned that a one-year implementation period may not be adequate. The companies needed the entire th ree-year MACT implementation period to roll out emissions standards that required far less testing and far less-reaching LDAR requirements than the proposed Subpart L will impose on th e same process units. Many member companies have determined that they will have to conduct pr ocess unit shutdowns to install testing ports to conduct required stack testing on units that rarely shut down. Ma ny member facilities may run out of time before completing the required te sting programs and before implementing the extensive LDAR programs. The Alliance requests that EPA allow facilities to petition for additional time to implement Subpart L, consiste nt with the extension petition system EPA used for Subpart OO for this calendar year.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name : Dave Stripe

Commenter Affiliation : Alliance for Responsible Atmospheric Policy

Comment Number : EPA-HQ-OAR-2009-0927-0067 Comment Excerpt Number: 4

Comment: The Alliance appreciates EPA allowing be st available monitoring methods for the entire 2011 calendar year since there’s a large amount of prep aration, monitoring and record keeping, that each reporting facility must esta blish to comply with proposed Subpart L. However, some may be concerned that a one-y ear implementation period may not be adequate.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number: 18

151Comment: The proposed rule requires completion of scoping testing, process emissions testing, and emission factor development by December 3 1, 2011. We request that EPA provide a five year period for this work, with the most signifi cant sources being addresse d during the first year. 3M estimates that the cost of completing this work will easily exceed $2MM. EPA’s response to

our comments could increase or decrease this estima te. For this estimate, we have assumed that the Subpart L analytical language will be aligned with what has been developed for Subpart OO and that work will not be required to synthesize chemicals that would be used to quantify unknowns. We do not believe that a testing progra m of this magnitude could be accomplished in the one-year time frame for the following reasons:

1. The costs and number of tests required is ex tensive. Highly trained personnel and specialized equipment will be required. 3M has developed cl ose working relationships with third party

contractors that conduct source test ing at its manufacturing locatio ns. In most cases, the same test equipment and personnel woul d be required to complete the testing specified for equipment

leaks.

2. Whereas testing for continuous process vents ca n typically be completed in a short period of time, e.g. three one-hour tests, te sting for batch processes could take weeks to complete due to extended batch cycles and due to the poten tial for an additional three tests.

3. A project of this scope will be better managed if indivi dual tests are conducted over an extended time period. Extensive preplanning will be required. Lessons learned as a part of early testing efforts can be used to refine and improve subsequent tests. If th e implementation period is extended, costs can be distribute d evenly over an extended time period. Any retesting would fall into the same five year cycle.

Finally, EPA should provide relief where unusual ci rcumstances prevent the completion of this work in the required time period.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Document Control Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number: 36

Comment: Section 98.124(j) states: “Initial scoping testing, emi ssions testing and emissions factor development must be completed by December 31, 2011.” Two years from promulgation will be needed to complete emission factor determinations per §98.123(b). Section 98.124(j) requires that all work be completed by December 2011. However, many units have long run times between shutdowns. As such, we request th e ability to utilize engineering calculations for three years. Economic conditions drive the fr equency that batch products are produced. Many facilities have 2 year cycle for s hut-downs. It is not economical or reasonable to require a forced

shut-down.

152Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 14

Comment: This section requires that all work be completed by December 2011. However, many units have long run times between shutdowns. As such, we request the ability to utilize engineering calculations for three years.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55.

Commenter Name: Rich Raiders

Commenter Affiliation: Arkema Inc.

Document Control Number: EPA-HQ-OAR-2009-0927-0085.1 Comment Excerpt Number: 57

Comment : We are unsure if adequate technology ex ists to perform the analyses required to meet EPA’s comprehensive GHG inventory goals. EPA should recognize that Subpart L, more so than other Part 98 source categories, is by ne cessity technology forcing. Previously, EPA has recognized when it engages in technology forcin g regulation by providing additional time (three years in the Maximum Achievable Control Technology program at 40 CFR 63). EPA should break with the Part 98 one year implementati on precedent for the Subpart L source category and provide reporters the opportunity to petition the agency for a second year of BAMM reporting. EPA should also utilize the petition process to allow reporters the opportunity to resolve emerging technology issues that will need to be addressed during implementation.

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55. EPA believes that the BAMM langu age and process can accommodate situations where the rule may be technology forcing.

Section 10.3 Other

Commenter Name: Jeff C. Muffat

Commenter Affiliation: 3M Center

Document Control Number: EPA-HQ-OAR-2009-0927-0111.1 Comment Excerpt Number: 1

153Comment: The various companies and facilities th at are included in this source category represent one of the most divers e collections of manufacturing operations that are covered under the Mandatory Reporting Rule (MRR). There have been various references to the Misc. Organic NESPHAP’s (MON) MACT standards during the ru lemaking process. There are many types of manufacturing operations, incl uding batch, continuous, and comb ined processes, containing varying amounts of the reportable materials and in varying quantities. We continue to encourage EPA to provide this source category with as mu ch flexibility as possible in preparing and managing their emission information. Most comp anies have very evolved emission tracking programs which should be leveraged as much possi ble. If quality control requirements have not been addressed by specific rule language, 3M ha s created the necessary architecture. A summary paragraph from our most recent third party audit that was conducted as a part of EPA’s Climate Leaders program is provided below: “In summar y, due to the unique nature of the chemical processes operated by 3M, GHG emissions cannot be estimated using published protocols. 3M has however expended great effort to collect theoretical and empiri cal data on the emissions from the processes, and the destru ction of emissions accomplis hed by the emissions control technology. It has also developed, and documented in its IMP, a rigorous process for tracking activity data and applying appropriate emission factors. CH2M HILL has performed a detailed

review of this information in its initial 3r d party verification effort for the complete 2002 inventory, and again in review of the 2007 a nd interim year chemical process emission

inventories. CH2M HILL’s conclu sion is that 3M’s chemical proc ess emission inventory is free

of material misstatement and suitable for th e intended purpose of public disclosure of its reduction to its total U.S. and gl obal GHG emission inventories.” (1)

Response: Please see the response to co mment number EPA-HQ-OAR-2009-0927-0085.1, excerpt 55 for a discussion of the additional flexibil ity to reporters that is being provided in the final rule compared to the April 2010 proposal. Th e final rule also adopts important flexibility provisions that were already included in the Ap ril 2010 proposal, for exam ple, allowing facilities

to choose between two different estimation me thods (emission factor and mass-balance) and allowing use of less rigorous methods for smalle r emission sources (e.g., the calculation methods adopted from the Miscellaneous Organic NES HAP and the Pharmaceutical NESHAP for vents emitting less than 10,000 mtCO 2 e annually) . EPA believes that the final rule appropriately balances flexibility with accuracy, timeliness, a nd consistency among facili ties in the rigor with which they estimate emissions from sources of similar sizes.

Commenter Name: Brian R. Keck Commenter Affiliation: Air Products and Chemicals, Inc. Comment Number: EPA-HQ-OAR-2009-0927-0106.1 Comment Excerpt Number: 6

Comment: Allow greater flexibility consistent w ith the objective for a reasonably accurate annual inventory report.

Response: Please see the response to comme nt EPA-HQ-OAR-2009-0927-0111.1, excerpt 1.

154Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Comment Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: EPA-HQ-OAR-2009-0927-DRAFT-0093-1

Comment: However, we are disappoint ed that this re-propose d subpart L is still too prescriptive. Fluorinated GHG pr oduction is complex, and numerous production processes are frequently located at the same plant. Having EPA prescribe calculation and monitoring methods removes the ability for sources to develop new pr otocols that better calcul ate the emissions from their facilities. Affected sources should be allowed to develop site -specific protocols for emissions measuring and monitoring, and detail such protocols in the required GHG Monitoring

Plan.

Response: Please see the response to comme nt EPA-HQ-OAR-2009-0927-0111.1, excerpt 1.

Commenter Name: Craig Holt Segall

Commenter Affiliation: Sierra Club

Document Control Number: EPA-HQ-OAR-2009-0927-0128.1 Comment Excerpt Number: 10

Comment: American industry produces hundreds of thousands of tons of fluorinated gases, including HFCs, PFC, SF 6 , NF 3 , HFEs, CFCs, and HCFCs annually – on the order of 440,000 tons a year, according to EPA. 2 These gases, if emitted, would translate into hundreds of millions

of tons of CO 2

. 3 Happily, most of this ma terial does not leak into the atmosphere from production facilities. But even at the fairly conservative leakage rate of between 1-1.5% annually that EPA estimates, combined production emissions reach 10.6 million mtCO 2 e annually. 4 If leaks are more significant, or the average GWP of leaked gases is higher than EPA believes, these emissions may be even larger. Thus, EP A must require rigorous reporting from this industry. The proposed rule can be strengthened to this end.

Response: EPA appreciates your comme nt. EPA believes that th e final rule appropriately balances the accuracy, timeliness, and consistenc y of emission estimates with flexibility and practicality for reporters. We discuss our responses to your specific recommendations in the preamble of the rule and el sewhere in this response to comments document.

Commenter Name: Lorraine Krupa Gershman

Commenter Affiliation: American Chemistry Council

Document Control Number: EPA-HQ-OAR-2009-0927-0092.1 Comment Excerpt Number: 25

2 Fluorinated Gas TSD at 4.

3 Id.

4 Id.

155156 Comment: The rule [in subpart 98.123(d)] states that sources shall “Estim ate annually the total mass of fluorinated GHG emissions from process vent s in either paragraph (c )(3) or (c)(4) of this section, as appropriate, and from equipment leak emissions in paragraph (d) using Equation L– 25 of this section.” The numbering appears to be in error, and the “(c)(3 ) or (c)(4)” should be “(b)(3) or (b)(4)”, and the “paragraph (d)” should be “paragraph (c).”

Response: The EPA agrees with this comment and ha s corrected the refere nces in §98.123(d) in the promulgated rule.

Commenter Name: John Dege

Commenter Affiliation: DuPont

Comment Number: EPA-HQ-OAR-2009-0927-0103.1 Comment Excerpt Number : 22

Comment: Apparent Typographical error in secti on 98.123(d) needs to be corrected. EPA: Section 98.123(d) states “Estim ate annually the total mass of fluorinated GHG emissions from process vents in either paragraph (c)(3) or (c )(4) of this section, as appropriate, and from equipment leak emissions in paragraph (d) using Equation L–25 of this section.” Comment: The numbering appears to be in error, and the “(c)(3 ) or (c)(4)” should be “( b)(3) or (b)(4)”, and the “paragraph (d)” should be “paragraph (c)”.

Response: Please see response for comm ent number EPA-HQ-OAR-2009-0927-0092.1, excerpt 25.