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

Subpart I - Electronics Manufacturing

# Subpart I – Electronics Manufacturing

U .S. Environmental Protection Agency Office of Atmospheric Programs Climate Change Division Washington, D.C.November 2010 2 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 I, Electronics Manufacturing. 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 se ctions, with each section focusing on a different broad category of comments on the ru le. In light of t he large number of

comments received and the si gnificant overlap between many comments, this document does not respond to each comment individually. Rather, EPA summarized and provided a single response to each signif icant argument, assertion, and question contained within the totality of comment s. Within each comment summary, EPA provides in parentheses one or more lists of Docket ID numbers for commenters who raised particular issues; however, these lists are not meant to be exhaustive, and EPA does not individually identif y each and every commenter who made a certain point in all instances, particularly in cases where mu ltiple commenters expressed essentially identical arguments.

EPA’s responses to comments are generally provided immediately following each comment summary. In some cases, EPA prov ided responses to specific comments or groups of similar comments in the preambl e to the final rulemaking. Rather than repeating those responses in this doc ument, EPA has refer enced 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 3 

### Table of Contents

1. Definition of the Source Category

.............................................................................................. 7

2. Reporting Threshold

...................................................................................................................... 9

2.1 Threshold Applicability Equations

........................................................................ 9

2.2 Alternative Methods for Determi ning Threshold Applicability

................... 11

2.3 De Minimis Threshold and Other Exemptions

............................................... 12

3. GHGs to Report

............................................................................................................................ 16

4. Emissions Calculation Methods

.............................................................................................. 17

4.1 Gas Consumption

.................................................................................................. 17

4.1.1 Facility-Wide Gas Specific Heel Factors

.................................................... 18

4.1.1.1 Accuracy and Precision of M easuring Inst ruments ................... 21

4.1.1.2 Exceptional Cir cumstanc e ......................................................... 24

4.1.1.3 Recalculation of Facility-Wide Ga s-Specific Heel Factors ......... 26

4.1.2 Apportioning Gas Consumption to Process Categories with a Facility-Specific Engineering Mode l Based on an Activity Indicator

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

4.2 Emission Estimation Methods fo r Semiconductor Facilities

..................... 33

4.2.1 Refined Method

.................................................................................................. 34

4.2.1.1 Other Methods of Cat egorizing Proc esses ................................ 36

4.2.1.2 Draft Default Emissions Fa ctors for Refined Process Categories.................................................................................36

4.2.1.2.1 Frequency and Process of Updates

............................................... 39

4.2.2 IPCC Tier 3 Method

.......................................................................................... 40

4.2.2.1 300 mm and Smaller Wafe r Technolog ies ................................ 40

4.2.2.2 Greater than 300 mm Wafe r Technolog ies ............................... 44

4.2.3 Alternative Methods for Ca lculating Emissions from

Semiconductor Facilities

............................................................................................... 46

4.3 CEMS (Continuous Emissions Monitoring System(s))

............................... 49

4.4 N 2 O

............................................................................................................................. 50

4.4.1 Default N 2 O Utilization Factors

...................................................................... 51

4.5 Heat Transfer Fluids

.............................................................................................. 53

5. Monitoring and QA/QC Requirements

.................................................................................. 57

5.1 Use of the 2006 ISMI Guidelines

...................................................................... 57

5.2 Controlled Emissions fr om Abatement Systems

.......................................... 58

5.2.1 Proper Installation, Oper ation, and Maintenance

.................................... 59

5.2.2 Accounting for Abatement System Uptime

................................................ 60

5.2.2.1 Semi E-10 Standard .................................................................. 62

5.2.3 EPA Default DRE Value

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

5.2.3.1 System Certif icati on .................................................................. 67

5.2.4 Proper Measurement of Abatement DRE

.................................................. 68

5.2.4.1 EPA’s DRE Pr otocol .................................................................. 69

5.2.4.2 Random Sampling Abatement S ystem Testing Program .......... 70

5.3 Other QA/QC Procedures

.................................................................................... 74

6. Data Reporting Requirements

................................................................................................. 77

6.1 DRE Reporting

........................................................................................................ 80

7. Records that Must be Retained

............................................................................................... 82

8. Cost Data/Burden

........................................................................................................................ 84November 2010 4 9. Confidential Busine ss Information (CBI)

............................................................................... 91

10. Uncertainty Analysis

................................................................................................................... 95

11. Other Subpart I Comments

....................................................................................................... 99

12. Relevant Comments from the Apr il 2009 Proposed Rule on Electronics Manufacturing

.............................................................................................................................. ........ 105

12.1 Calculating GHG Emissions: Em ission Estimation Methods for

Semiconductor Facilities

................................................................................................. 105

12.2 Monitoring and QA/QC Requirem ents: Use of the 2006 ISMI

Guidelines

............................................................................................................................ 112

13. Other Changes

........................................................................................................................... 115 Appendix A: List of Commenter s Sorted by Submission Number

....................................... 118 Appendix B: Additional Comments on the EPA DRE Protocol (Submitted by SIA – EPA-HQ-OAR-2009-0927-0131)

................................................................................................... 119November 2010 5 List of Acronyms

BAU Business As Usual

CAA Clean Air Act

CBI Confidenti al Business Information

CEMS Continuous Emissions Monitoring System

CFR Code of Federal Regulations

CVD Chemical Vapor Deposition

DRE Destruction or Removal Efficiency

Electronics Manufacturing TSD Technical Support Document for Process Emissions

from Electronics Manufact ure (e.g., Micro-ElectroMechanical Systems, Liqu id Crystal Displays, Photovoltaics, and Semiconductors): Proposed Rule for Mandatory Reporting of Greenhouse Gases 1

EPA U.S. Envir onmental Protection Agency

EPA DRE Protocol EPA’s Protocol for Measuring Destruction or Removal Efficiency of Fluorinated Greenhouse Gas Abatement Equipment in Electronics Manufacturing (EPA 430-R10-003)

Final MRR Final Rule, Mandat ory Reporting of Greenhouse Gases, October 30, 2009 (74 FR 56260)

Fluorinated GHG Fl uorinated Greenhouse Gas

F-HTF Fluorinated Heat Transfer Fluid

FTIR Fourier Transform Infrared Spectroscopy

GAO U.S. Government Accountability Office

GHG Greenhouse Gas

GWP Global Warming Potential

HAP Hazardous Air Pollutants

HTF Heat Transfer Fluid

IPCC Intergovernment al Panel on Climate Change

ISMI International SEMAT ECH Manufacturing Initiative

ITRI Industrial Technology Research Institute

ITRS International Technology Roadmap for

Semiconductors

1 This is the REVISED November 2010 version unl ess otherwise noted as the March 22, 2010 version.November 2010 6 JETIA Japan Electronics and Information Technology

Industries Association

LED Light-Emitting Diode

MES Manufacturing Execution Software

MFC Mass Flow Controller

MOU Memorandum of Understanding

MtCOe Metric tons of Carbon Dioxide Equivalents

NDIR Nondispersive Infrared

NIST National Institut e of Standards and Technology

NODA EPA’s Notice of Data Availability; Default Emission Factors for Semiconductor Manufacturing Refined Process Categories, May 2010 (75 FR 26904)

Pa Pascal (unit of pressure)

PFC Perfluorocompound

POU Point of Use

PV Photovoltaic

RFID Radio Frequency Identification

RSASTP Random Sampling Ab atement System Testing Program

R&D Research and Development

SIA Semiconductor Industry Association

SIP State Im plementation Plan

TFT-FPD Thin-Film-Transistor Flat Panel Display

Tier 1 2006 IPCC Tier 1 Method (Volume 3, Chapter 6)

Tier 2b 2006 IPCC Tier 2b Method (Volume 3, Chapter 6)

Tier 3 2006 IPCC Tier 3 Method (Volume 3, Chapter 6)

VOCs Volatile Organic CompoundsNovember 2010 7 

### 1. Definition of the Source Category

Comment Summary 1-a: One commenter (0110) proposed that if light-emitting diode (LED) production is to be included in the fi nal rule, the emissions should be calculated using the Modified Tier 2b Method 2 since the number and amount of fluorinated greenhouse gases (fluorinated GHGs) used is much lower in LED production than in semiconductor manufacturing.

Response 1-a: In the final rule (§98.90), EPA cl arified that under the electronics manufacturing source category, semiconducto rs include, among others, light-emitting diodes (LEDs). EPA made this clarificat ion because LEDs are semiconductor light sources—when a LED is switched on, electr ons are able to recombine with holes within the device, releasing energy in the form of light whose color is governed by the nature of the semiconductor. Many LE Ds are manufactured on a wafer (usually different than silicon) using methods that are similar to the manufac ture of integrated

circuits. 3 Therefore, facilities t hat manufacture LEDs must use either the Tier 2c

method 4 or the Tier 2d method, 5 as appropriate, consistent wit h all other facilities that

manufacture semiconductor devices.

EPA’s information on LED manufacturing facilit ies is limited and the commenter did not provide any quantitative information to support the claim that the num ber and amount of fluorinated GHG used in LED production is much lower than in semiconductor manufacturing. EPA has concluded that it has no information to support subdividing

semiconductor manufacturers into different distinct semiconductor device types, each required to use a different emission estimation method.

Comment Summary 1-b: One commenter ( 0095) stated that t he proposed rule as written did not distinguish between electronics manufacturing facilities and facilities that manufacture the equipment used to manufac ture electronics (tool research and development [R&D] facilities). The commenter asserted that such facilities may engage in plasma etching, chamber cleaning, and CVD processes as part of their R&D activities, but are not engaged in “producti on processes” as the wafers are not completely manufactured but go through limited semiconductor processes. The

2 EPA proposed in the Modified Tier 2b method in the April 2010 proposal for other Electronics Manufacturing facilities including those that manufacture LCDs, MEMS, and PV.

3 For reference that many LEDs are produced on single wafer see: http://apps1.eere.energy.gov/buildings/pub lications/pdfs/ssl/perkins_fairfax09.pdf.

4 Under the final rule, semiconductor manufacturi ng facilities that manufacture devices on wafers measuring 300 mm or less in diameter and that hav e an annual manufacturing capacity equal to or less than 10,500 m 2 of substrate are required to estimate and report their emissions using the Tier 2c method. See preamble section D, Electronics Manufacturing, (S ubpart I), section 1 (“Summary of the Final Rule”)

for a detailed discussion on the Tier 2c method.

5 Under the final rule, semiconductor manufacturi ng facilities that manufacture devices on wafers measuring 300 or less mm in diameter and that have an annual manufacturing capacity greater than
10,500 m 2 of substrate are required to estimate and repor t their emissions using the Tier 2d method. See preamble section D, Electronics Manufacturing, (S ubpart I), section 1 (“Summary of the Final Rule”)

for a detailed discussion on the Tier 2d method.November 2010 8 commenter asserted that it would be cha llenging to calculate greenhouse gas (GHG) emissions based on manufacturing capacity or wafer starts because these metrics are

not relevant for R&D facilities. The co mmenter also noted that semiconductor R&D facilities contribute minimally to the overall GHG emissions from electronics manufacturing sources. To this end, the co mmenter argued that R&D facilities should be exempt from the proposed rule to hel p facilitate the development of new technologies.

Response 1-b: Under the final rule, per §98.90(a), fa cilities that engage in the following production processes are covered under the electronics manufacturing source category: (1) Electronics manufacturing production process in which the etching process uses plasma-generated fluorine atoms and other reactive fluorine- containing fragments, which chemically react with exposed thin-films (e.g., dielectric, metals) or substrate (e.g., silicon) to selectively remove portions of material; (2) Electronics manufacturing production process in which chambers used for depositing thin films are cl eaned periodically using plas ma-generated fluorine atoms and other reactive fluorine-containing fr agments from fluorinated and other gases; (3) Electronics manufacturing production process in which wafers are cleaned using plasma-generated fluorine atoms or other reactive fl uorine-containing fragments

to remove residual material from wa fer surfaces, including the wafer edge; (4) Electronics manufacturing production process in which the chemical vapor deposition (CVD) process or othe r manufacturing processes use N 2 O; and (5) Electronics manufacturing production process in which fluorinated GHGs are used as heat transfer fluids (HTFs) to cool process equipment, to control temperature during device testing, to clean substrate surfaces and other parts, and for soldering (e.g., vapor phase reflow). If a facility engages in the covered proc esses listed above and they meet the threshold per §98.91(a), it is required to estimate and report their emissions under subpart I (Electronics Manufacturing), with the exception of emissions from R&D

activities. Under the Final Mandatory Reporting Ru le (Final MRR), R&D activities (as defined in 40 CFR 98.6) are not considered to be part of any source category subject to the rule. If a facility engages in R&D activities , the facility is not required to report the emissions from that R&D activity. See t he preamble to the Final Mandatory Reporting Rule (Final MRR) for a more detailed discu ssion on the exemption for R&D activities (74 FR 56285, October 2009). Pursuant to 40 CFR 98.6, “Research and development means those activities conducted in process units or at laboratory bench-scale settings whose purpose is to conduct research and development 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.”November 2010 9 

### 2. Reporting Threshold

Comment Summary 2-a: One commenter (0128) supported the reporting threshold of 25,000 MtCO 2 e (metric tons of carbon dioxide equivalents) per year, which would embrace roughly 96 percent of emissions from semiconductor facilities.

Response 2-a: EPA thanks the commenter for thei r input. EPA is maintaining the 25,000 MtCO 2 e per year reporting threshold for el ectronics manufacturing facilities in the final rule (see §98.91). See preambl e section D, Electronics Manufacturing (subpart I), section 1, for a summary of the reporting threshold for electronics manufacture and the preambl e to the Final MRR (74 FR 56272) for additional responses to comments on EPA’s selection of a 25,000 MtCO 2 e per year reporting

threshold.

2.1 Threshold Applicability Equations

Comment Summary 2.1-a: One commenter (TRANS-DC-02) asserted that proposed Equation I-1 appears flawed, as it lacks a st ep to convert process emissions to CO 2 equivalents based on global wa rming potential (GWP).

Response 2.1-a: EPA thanks the commenter for their in put. In the final rule, EPA has corrected the threshold applicability equation, Equation I-1, as well as Equations I-2 and I-3, to include a GWP term (a gas-appropriate GWP as provi ded in Table A-1 to subpart A of part 98) used to conver t process emissions to CO 2 equivalents.

Comment Summary 2.1-b: One commenter (TRANS-DC- 02) asserted that the proposed threshold applicability determinat ion equation for semiconductor facilities (Equation I-1) was a potential to emit calculation based on 100 percent of the manufacturing capacity of a fa cility, as opposed to an actual emission calculation that should serve as a reporting trigger.

Response 2.1-b: EPA agrees with the commenter that the threshold applicability equation for semiconductor facilities is based on a facility’s potential to emit. EPA is finalizing this requirement for the following r easons: 1) Calculating a facility’s potential emissions is relatively simple and less burde nsome than calculating actual emissions; and 2) Studies indicate facilities us ing fluorinated GHG abatement systems may

underestimate their actual emissions due to widespread overestimation of these systems’ fluorinated GHG destruction or remo val efficiencies (DRE) (see the preamble to the proposed rule (75 FR 18652, April 20 10) for a more detailed discussion on EPA’s rationale for not permitting a facility to acc ount for destruction by abatement systems in the threshold applicabi lity calculation).

Although the threshold applicability equations for subpart I are based on potential to emit, the cease-reporting provis ions in the Final MRR allow facilities, regardless of their applicability threshold, to cease reporting ba sed on the facility’s actual emissions as submitted in their annual report. See the pr eamble to the October 2009 final rule for aNovember 2010 10 more detailed discussion and responses to comments related to the provisions to cease reporting (74 FR 56276, October 2009).

Comment Summary 2.1-c: One commenter (0110) assert ed that “full planned design capacity” (used in the threshold applicabi lity equations) is ambiguous, because actual capacity fluctuates due to process changes made in a fab and varying manufacturing levels spurred by the dynamic nature of the industry.

Another commenter (0095) asse rted that the 2006 IPCC Tier 1 (“Tier 1”) method does not specify whether the manufacturing capa city is based on the volume of wafers manufactured or the number of wafer passes. The commenter also stated that it was

unclear whether wafers that are processed without the use of GHGs were to be included in manufacturing capacity. Lastly, the commenter noted that a semiconductor facility may also use wafers for proc esses that do not use GHGs.

Response 2.1-c: In the final rule, in §98.91,EPA has modified the term “full designed capacity” from the April 2010 proposed rule to be “100 percent of annual manufacturing capacity.” For further clar ity, EPA also provided a new equation, Equation I-5 in the final rule in §98.91, for facilities to use w hen determining this capacity value in threshold applicability calculations. Equation I-5 will be used to determine 100 percent of annual manufacturing capacity of a facility by summing the area of maximum designed

substrate starts of a facility per month over the reporting period.

In addition, also for further clarification in §98.98, EPA defined the term “maximum designed substrate starts” as the maximu m quantity of substrates, expressed as

surface area that could be started each mont h during a reporting y ear, if the facility were fully equipped as defined in the facility design specifications and if the equipment were fully utilized.

In response to the commenter who asserted t hat it was unclear whether manufacturing capacity would include wafers used for pr ocesses that do not use fluorinated GHGs, EPA is requiring all substrate starts, regardless of their m anufacturing fate, be included as part of the maximum designed substrate st arts. This requirement is being adopted to simplify and minimize the burden asso ciated with the threshold applicability

determination and to make the results of the determination more conservative.

Comment Summary 2.1-d: One commenter (0128) suppor ted the exclusion of emission reductions from abatement technologies in calculations to determine whether a facility meets the reporting threshold. The commenter asserted that given EPA’s

statement that manufacturers’ estimates of abatement system efficacy is often inaccurate, leading to overstated system efficiencies resulting from improper installation, maintenance, or operation, EPA is correct to exclude the use of abatement systems in determining th reshold applicability.November 2010 11 Response 2.1-d: EPA thanks the commenter for their in put. EPA is finalizing a method for the threshold applicability determination that excludes emission reductions from abatement technologies. S ee the Electronics Manufactu ring TSD available in the docket (EPA-HQ-OAR-2009-0927) for a discussion supporting this exclusion.

2.2 Alternative Methods for Dete rmining Threshold Applicability

Comment Summary 2.2-a: As an alternative to EPA’s proposed threshold applicability calculation, a commenter (0110) proposed applyi ng Tier 1 emission factors to annual fluorinated GHG consumption for threshold dete rmination in a manner si milar to that of photovoltaic (PV) manufacturing.

Response 2.2-a: EPA disagrees with the comm enter that proposed to allow facilities to determine their threshold applicability by appl ying Tier 1 emissi on factors to annual fluorinated GHG consumption. The method s uggested by the commenter is not a valid or plausible method. Tier 1 emission factors are based on the known capacity of a facility; these emission factors have units of the mass of gas emitted per area (m 2 ) of substrate produced. To apply an emission fact or with these units to a gas consumption number, also in the units of mass of gas, woul d result in an emission estimate that does not physically or mathematically make s ense. EPA would like to clarify that the threshold determination method for PV facilities is based upon gas consumption and gas appropriate GWPs, not gas consum ption and Tier 1 emission factors.

Comment Summary 2.2-b: One commenter (0095) asse rted that semiconductor facilities should be permitted to use the 2006 IPCC Tier 2b Method (“Tier 2b”) for

threshold determination instead of the Tier 1 Method, provided that the facility uses abatement systems. As an al ternative, the commenter suggested that facilities be

allowed to use an alternative destruction re moval efficiency (DRE) value that exceeds the default IPCC DRE value based on section 98.94 of the proposed rule. The

commenter asserted that the Tier 1 met hodology does not distinguish between the

volume of wafers manufactured or the number of wafer passes.

The commenter asserted that the use of the Tier 2b method should be allowed since

the Tier 2b method is more accurate for ev aluating actual emissi ons. The commenter argued that the use of the Tier 2b methodology for th reshold determination would be consistent with the requirements of AB32 Greenhouse Gas Emission Reduction, California Air Resources Board (reference: California Code of Regulations, Title 17, Subchapter 10, Articl e 4, Subarticle 2).

Response 2.2-b: EPA does not agree with the comm enter that the threshold applicability requirements in the final rule should be modified. EPA is not modifying the applicability threshold requirements because, as compared to the Tier 2b method, the Tier 1 method is relatively simple and le ss burdensome to determine whether or not a facility is required to report. Further, EPA is not permitting the use of DREs in the threshold applicability determination for reasons previously stated in the preamble to the April 2010 proposed rule (75 FR 18659). Please see the preamble to the April 2010November 2010 12 proposed rule (75 FR 18659, April 2010) fo r a more detailed discussion on EPA’s rationale for not permitting a facility to acc ount for destruction by abatement systems in the threshold applicability calc ulation. Please also see re sponse to comment 2.1-c for

information on the how EPA has clarified the th reshold applicability determination using

the Tier 1 method in the final rule.

2.3 De Minimis Threshold and Other Exemptions

Comment Summary 2.3-a: Five commenters (0089, 0099, 0110, 0123, and 0131) noted facilities routinely employ small quant ities of chemicals used as HTFs and for other uses. The commenters expressed c oncern EPA has not established a de minimis standard for reporting. Tw o commenters (0123 and 0110) recommended a de minimis level be established for calculation and repor ting emissions from the use of HTFs. Another commenter (0099) asse rted that establishing a de mi nimis threshold for HTFs

would be “consistent with t he refrigerant management requi rements found in 40 Code of Federal Regulations (CFR) part 82 wh ich apply to the most detailed tracking requirements only to refrigerant units contai ning more than 50 pounds of refrigerant.” Other commenters (0089, 0131) expr essed similar sentiments.

One commenter (0089) asserted that the definition of “f luorinated greenhouse gas” found in 40 CFR 98.6 is broad and using th is definition without a de minimis value below which reporting is not required may cause problems. Two commenters (0089 and 0099) noted that companies often experiment with a vari ety of chemicals before high volume manufacturing, and requiring t hat emissions factors be developed, and emissions reported will present a significant burden for a small amount of emissions. These commenters (0089 and 0099) stated that it is also lik ely that there are many gases for which a GWP value has not been established. One commenter (0089) asserted that the requirements be revised to require reporting for only those fluorinated GHGs which are used in excess of 100 pounds and that have an es tablished GWP. The commenter also suggested that the same criteria be applied to the gas consumption reporting required in §98.96(f)

.

One commenter (0099) proposed that EPA incl ude provisions to allow facilities to exclude from emissions calculations any fluorinated GHG that does not have an established GWP or comprises less than 5 pe rcent of total usage of fluorinated GHGs where: 1) The de minimis amount of the fl uorinated GHG used in etch comprise less than 5 percent of the total usage of all fluorinated GHG co mpounds in etch, 2) the de

minimis amount of the fluorinated GHG used in CVD chamber cleaning comprises less than 5 percent of the tota l usage of all fluorinated GH G compounds in CVD chamber cleaning, 3) the de minimis amount of the fl uorinated HTF comprises less than 5 percent the total usage of all fluorinated HTFs compounds.

Similarly, another commenter (0131) propos ed that EPA include provisions to allow

facilities to exclude from emissions calculat ions any fluorinated GHGs that comprises less than 5 percent of the total usage of fl uorinated GHGs where: 1) The de minimis

amount of the fluorinated GHG used in etch comprises less than 5 percent of the total usage of all fluorinated GHG compounds in etch, 2) the de mini mis amount of theNovember 2010 13 fluorinated GHG used in CVD chamber cleani ng comprises less than 5 percent of the total usage of all fluorinated GHG compound s in CVD chamber cleaning, 3) the de

minimis amount of the fluorinated GHG used in wafer cleaning comprises less than 5 percent of the total usage of all fluorinat ed GHG compounds in wafe r cleaning, 4) the de minimis amount of the fluorinated HTF comp rises less than 5 percent the total usage

of all fluorinated HTFs compounds.

Response 2.3-a: EPA does not agree with the comments that a de minimis threshold

should be established for either HTF emissi ons or process fluorinated GHG emissions. When EPA published the Final MRR, EPA dete rmined de minimis provisions were not necessary because a de minimis provision would compromise the quality and

usefulness of the data co llected (74 FR 56260, Oct ober 2009). For additional background on EPA’s decisions to exclude de minimis provisions, please see response to comments in the preamble to the Fi nal MRR (74 FR 56278-56279, October 2009) and also ‘‘Reporting Methods for Small Emi ssion Points (De Minimis Reporting)’’ (EPA– HQ–OAR– 2008–0508–0048).

With respect to the comments that reporting emissions from chemicals that facilities use in small quantities to experiment is bur densome, EPA recognizes that it may be burdensome for facilities to develop facility- wide gas-specific heel factors and emission

factors for fluorinated GHGs and N 2 O that are used in small quantities. In response, consistent with the Final MRR, in §98.93

, EPA has made changes to the calculation requirements that further reduce any need fo r de minimis reporting provisions by allowing simpler methods for fluorinated GHGs and N 2 O that are used in small quantities. For any fluorinated GHG used in production processes or N 2 O for which a facility consumes 50 kg or less during a r eporting year, the facility has the option to

assume that the amount of that gas emitted is equal to the amount of that gas consumed. To determine the amount of gas consumed, EPA is allowing facilities to assume that the gas-specific heel factor is equal to zero. EPA has provided this option only for fluorinated GHG process gases and N 2 O. EPA has not made any modifications to the reporting requirements for HTFs becau se EPA concludes that the mass balance method is simple and will effectively capture all emissions of HTFs.

With respect to commenter’s assertion t hat EPA should adopt a de minimis threshold

for HTFs because it is “consistent with the refrigerant management requirements found in 40 Code of Federal Regulations (CFR) par t 82 which apply the most detailed tracking requirements only to refrigerant units cont aining more than 50 pounds of refrigerant,” EPA does not agree that it should adopt a thre shold designed for a specific existing program. While EPA is not opi ning on the commenter’s charac terization of 40 CFR part 82, EPA does not agree with t he commenter’s suggestion because the purpose of this

rule is to collect data for use in devel oping future GHG policies and programs. Collecting accurate data of GHG emissions is important to the futu re value of the data for informing policy decisions and desi gning new GHG policies and programs. Receiving data on emissions from HTFs will provide EPA with comprehensive information on all emissions, including qua ntities and sources, from electronics manufacturing facilities.November 2010 14 In response to the commenters’ suggestion t hat only chemicals with established GWPs should be reported, EPA does not agree. EPA acknowledges there may be cases where a facility is required to report fluor inated GHG emissions for which GWPs have not yet been assigned in either IPCC or Wo rld Meteorological Organization (WMO) Scientific Assessments (i.e., fluorinated GHGs for which Table A–1 of 40 CFR part 98, subpart A does not provide GWPs). As ack nowledged by commenters, Table A-1 of 40 CFR part 98, subpart A is not a complete listing of current or potential fluorinated GHGs; the IPCC and WMO lists on which it is based reflect onl y the facts that the listed materials have been synthesized, their atmospher ic properties investigated, the results published, and the publications found by t he IPCC and WMO Assessment authors. Table A–1 omits some fluorinated GHGs, and it unavoidably omits future fluorinated GHGs that have not yet been synthesized. Giv en the radiative chemic al properties of the carbon-fluorine bond, any fluorocarbon emitted into the atmosphere may have a significant GWP. However, the lack of GWPs for some fluorinated GHGs will not impede reporting because EPA is requiring t hat emissions be reported on a mass basis

rather than a CO 2 e basis.

Reporting of fluorinated GHGs that do not appear in Table A–1 of 40 CFR part 98, subpart A will provide valuable information on types of fluorinated GHGs being used in electronics manufacturing. Further, this in formation can be used to assess the volume

of emissions for which GWPs have not been evaluated and to help prioritize the evaluation of GWPs. For more responses to comment on the definition of “fluorinated GHG” and the reasons why EPA is requiring fac ilities to report fluorinated GHGs that do not appear in Table A-1, please see the preamble to the Final MRR (74 FR 56348, October 2009).

EPA anticipates that as GW Ps are evaluated or reevaluated by the scientific community, the Agency will update Table A– 1 of 40 CFR part 98, subpart A through notice and comment rulemaking. EPA may also, through rulemaking, establish a more proactive process for ensuring that GWPs ar e appropriately evaluated or reevaluated. Please also see the Response to Comm ent Document for OO available at http://www.epa.gov/climatechange/emissi ons/downloads09/documents/SubpartOOSuppliersofIndustrialGHGs.pdf.

Comment Summary 2.3-b: One commenter (0131) stat ed that “small electronics manufacturing processes with wafer produc tion capacities of less than 1,080 m 2 emit

less than 5% of the 25,000 metric ton CO 2 e reporting threshold for this rule. However, some of these small processes are located at large integrated manufacturing facilities that have on-site power generating utilit ies (e.g. Boilers for generating heat and electricity). GHG emissions fr om combustion operations at these facilities typically exceed the 25,000 tons CO 2 e threshold and, therefore, br ing the entire facility into the reporting rule, including the small electronics manufacturing process.” The commenter proposed revisions to the regulatory text of subpart I, secti on 98.91, to exclude electronics manufacturing processes with a production capacity of 1,080 m 2 or less.November 2010 15 Response 2.3-b: EPA does not agree with the comment er’s proposed regulatory text revisions that exclude reporting emissions from processes with pr oduction capacities of
1,080 m 2 or less. Any facility that engages in the production processes defined in the

electronics manufacture source category and exceeds the 25,000 MtCO 2 e threshold, with both process and combustion emission s, must report fluorinated GHG and N 2 O emissions and consumption for all of t he process covered by the electronics manufacture source category. 6 EPA does not agree that particular processes at a facility should be excluded from facility r eporting because this would provide EPA with an incomplete picture of actual facility emi ssions. EPA has also concluded that it is necessary to include combustion emissions in the threshold determination because many electronics manufacturing facilities emit GHGs from both manufacturing processes and combustion sources. It is important to EPA t hat both process and

combustion emissions are considered in threshold determinations so EPA can gain a more complete picture of to tal U.S. emissions to inform future policy and regulatory

decisions.

In the final rule electronics manufacturing facilities that meet or exceed the 25,000

metric tons of CO 2 e threshold must report, which is co nsistent with most other subparts of the rule. Please see the preamble to the Final MRR for more details on the appropriateness of this threshold for the MRR, and how this threshold was selected (74 FR 56271, October 2009).

In response to the commenter’s concer n that small electronics manufacturing processes may be brought into the GHG R eporting Program, and this will impose some level of regulatory burden, EPA points to th e fact that efforts have been made to help simplify reporting requirements for relatively sm aller emissions sources. First, the rule excludes small facilities through the applicat ion of the 25,000 metric tons of CO 2 e threshold. This threshold balances the number and size of reporter with the coverage of emissions. Second, reporters must report only the emissions from sources for which calculation methods are prov ided in the rule. Calculat ion methods are generally not included for smaller sources of emissions (e.g., coal piles on industri al sites). In some cases, where a source category includes rela tively small emission sources, the rule provides simplified emissions calculation me thods for those source s. Given that EPA has taken steps to simplify emissions monitoring methods in this rule, EPA has concluded that reporting cutoffs, such as t he production capacity cutoff proposed by the
commenter, are not necessary.

6 As defined in § 98.6, a facility means any physical property , plant, building, structure, source, or stationary equipment located on one or more contiguous or adjacent properties in actual physical contact or separated solely by a public roadway or other public right-of-way and under common ownership or common control, that emits or may emit any greenh ouse gas. Operators of military installations may classify such installations as more than a singl e facility based on distinct and independent functional groupings within contiguous military properties.November 2010 16 

### 3. GHGs to Report

Comment Summary 3-a: One commenter (0099) asserted that the definition of GHGs is much broader than the Kyoto basket of gase s. The commenter fu rther stated that the definition of fluorinated GHGs is very br oad and potentially includes many materials that have not been quantified. The co mmenter further noted that it is unclear whether accurate measurement methods (or GWP values) even exist for these compounds. The commenter suggested that initially the rule should focus on the Kyoto Protocol basket of gases and NF 3

.

Another commenter (0108) s uggested that EPA’s online GH G emissions reporting tool must easily accommodate mass emissions r eporting in an uncomp licated manner for

HTFs and fluorinated GHGs like C 5 F 8 for which calculation of CO 2 e is not possible because GWPs were not published in subpart A, Table A-1.

Response 3-a: The definition of fluorinated GHG wa s promulgated in the Final MRR, and EPA did not revisit it in this rulemaking. For response to comments regarding the

definition of “fluorinated GH G” please see the preamble to the Final MRR (74 FR 56348, October 2009). Please also see the Response to Comment Document for OO

available at http://www.epa.gov/climatechange/emissi ons/downloads09/documents/SubpartOOSuppliersofIndustrialG HGs.pdf.

In regards to the commenters’ concerns about GWPs that may not exist or be published, please see respons e to comment 2.3-a.

EPA acknowledges the commenter’s concer n about the reporting tool. While EPA is currently developing the reporting tool, at this time, EPA does not anticipate that reporting emissions from gases that do not have GWPs will be a problem because semiconductor manufacturing facilities ar e required to report emissions on a mass basis as opposed to a CO 2 e basis. Please see the preamble to the Final MRR for more information on the electronic reporting tool (74 FR 56282, October 2009).November 2010 17 

### 4. Emissions Calculation Methods

4.1 Gas Consumption

Comment Summary 4.1-a: Five commenters (0099, 0110, 0112, 0123, and 0131) did not support the proposed gas inve ntory requirements as part of determining overall gas consumption. Three comm enters (0099, 0112, and 0131) expec ted that, year-to-year, the total inventory of each gas would not vary widely. Commenters (0099, 0110, 0112, 0123, and 0131) also suggested t hat if gas usage for a prev ious reporting year is “under-reported” or “over-reported,” the usa ge for the following r eporting year would

account for the deficit or excess amount.

One commenter (0110) stated t hat site purchase and inventory records are typically used to track gas usage. The commenter asse rted that this standard practice is widely accepted for criteria pollutants under t he Clean Air Act (CAA) and for emissions accounting under state implement ation plans (SIPs) approved by EPA. The commenter

noted that these methods are also used fo r compliance and enforcement of emission limitations under the CAA, and t hat they believe that a similar approach can be used for estimating and reporting GHG emissions. In line with these sentiments, another commenter (0131) suggested that only purc hase records showing acquisitions and disbursements, combined with heel factors, be utilized to determine consumption; the commenter asserted that cylinders changed out prematurely do not need to be accounted for separately from purchase records.

Response 4.1-a: EPA does not agree with the comm enters that asserted purchase records would be sufficient for tracking gas c onsumption, or that only purchase records showing acquisitions and disbursements co mbined with heel factors should be utilized to determine consumption; as opposed to purchase records, gas inventories, and facility-wide gas-specific heel factors. In the final rule, EPA is maintaining the requirement for facilities to determine t he amount of gas consumed based on a mass balance method, which utilizes an inventory of gas at a facility. The use of this method, which involves an inventory of gas stored in containers in the begi nning and end of the reporting year, ensures that any fugitive emi ssions that may arise from gas handling are accounted for, and that fluctuations in gas c onsumption from year-t o-year at facilities

are accounted for. While comme nters note that year-to-year the total inventory of each gas would not vary widely, information was not provided to EPA to verify this statement.

With respect to the commenter that asserted chemical use should be tracked using site purchase and inventory records, similar to how emissions are calculated for other CAA requirements and under SIPs approved by EPA, it is important to clarify that the purpose of this rule differs from those r egulatory programs. In contrast to other regulatory programs which generally focus on whether a facility's emissions are below a specified limit, this rule focuses on establis hing each facility’s annual GHG emissions in metric tons per year with the goal of gatheri ng accurate facility-level data. EPA plans to use such data to inform future policy and re gulatory decisions. EPA has concluded that the gas consumption requirements in subpart I help ensure that this goal is achieved.November 2010 18 Comment Summary 4.1-b: In response to EPA’s request for comment on how to account for the amount of gas in contai ners in service in an annual inventory, commenters did not support determining the quantit y of gas in partially used in-service cylinders at the end of the reporting year , citing a significant amount of burden and difficulty in complying with this proposed requirement with little improvement in calculation certainty. One commenter (0131) cited burden as an issue in particular because a facility may have hundreds of gas cylinders in service.

Response 4.1-b: EPA agrees with commenters that t he additional amount of labor and difficulty required to inventory the quantity of gas in partially used in-service cylinders at the end of a reporting year is not justified by any gains in accuracy. To reduce burden,

EPA has modified the rule to allow facilities to account for the total quantity of gas in

containers in service at the end of a reporting year as if the in-service containers were

full. Facilities must also then account for this same quantity in the inventory of gas stored in containers at the beginning of the subsequent reporting year. EPA understands that any “under-repor ting” or “over-reporting” t hat is a consequence from

this modification will be balanced out in s ubsequent reporting years. EPA believes this

modification will have a minimal effect on the accuracy of emission estimates.

4.1.1 Facility-Wide Gas Specific Heel Factors

Comment Summary 4.1.1-a: Two commenters (0099 and 0131) proposed that in lieu of using heel factors, EPA should permit fa cilities to determine gas consumption by tracking individual containers. The comm enters stated that tracking individual gas containers will provide consumption estimates that are as accurate as EPA’s proposed method of using heel factors.

Response 4.1.1-a: EPA is not clear as to what t he commenters are suggesting. If the commenters are suggesting that gas containers can be tracked but that the heels of gas containers should not be accounted for, EPA does not agree. By trackingindividual cylinders and not accounting for cylinder heels, as opposed to using facilitywide gas-specific heel factors to estimate gas consumption, the estimates will not be

accurate. As one commenter (0112) explained, “The heels that are returned to the manufacturer represent 4.3 percent of the total gas used.” T herefore, in not accounting for heels in gas consumption estimates, a facility would be knowingly over-estimating gas consumption. This conflicts with EPA’s intention to gather accurate facility-level information. In addition, EPA understands that many electronics manufacturing facilities already estimate gas consumption based on purchase records and a default factor. According to one commenter (0131), 81 percent of semiconductor facilities that participated in the 2009 ISMI survey used purchase records and a default heel factor to estimate gas consumption. EPA also underst ands that in business as usual (BAU) facility operations, mass-based or pressure -based trigger points for change out are used to determine when gas containers are to be changed. EPA is therefore requiring these trigger points for change out be used to calculate facility-wide gas-specific heel factors for each gas container type, based on trigger points established as part of facility operations, rather than permitting fac ilities to track indivi dual containers.November 2010 19 Comment Summary 4.1.1-b: One commenter (0095) reques ted clarification on the average facility-wide gas-specific heel factor and whether it is a monthly or yearly

average.

Response 4.1.1-b: EPA is requiring gas consumption to be determined based on knowledge of the actual amount of each gas consumed during the reporting period by determining a gas and facility-specific heel fa ctor for each container type used during a reporting year. This approach does not requi re the facility to develop a monthly or annual average heel factor; rather, EPA is re quiring the facility to develop a facilitywide, gas-specific heel factor that is based on the concept of a "constant" facility-wide gas-specific “trigger point for change out.” This trigger point for change out denotes a specific amount of gas in a cylinder--an am ount that requires the cylinder to be exchanged, typically for a full cylinder, at or just before the trigger amount is reached. That triggering amount, along with the initial full mass of a gas container, may be used to calculate heel factors throughout a repor ting period provided the trigger point does not change by more than 5 perc ent. If the trigger point s hould change by more than 5 percent, then the new trigger point is to be used to calculate gas consumption for the remainder of that reporting period. The am ount of gas consumed for a reporting year would be the sum of a gas consumed for each period in a reporting year during which the trigger point for change out did not vary by more than 5 percent. EPA believes this method is appropriate and reliable because for a "constant" trigger amount, the corresponding heel will also be co nstant provided cylinders of the size for that trigger

are filled to the same amount. EPA understands t hat it is the practice of gas suppliers to fill cylinders of the same size and the same gas with identical amounts.

Comment Summary 4.1.1-c: Four commenters ( 0099, 0100, 0112, and 0131) supported the use of site-specific gas heel fact ors in conjunction with purchase records. One commenter (0112) asserted t hat the use of facility-wide ga s-specific heel factors at their facilities increased the accuracy of the estimated gas consumed by 5.9 percent, and increased the accuracy of the emission calculations. Two commenters (0099 and 0131) asserted that the use of site-specific gas heel factors would greatly improve the accuracy of gas usage determinations over the IPCC default heel factor of 10 percent. One commenter (0131) asserted that using site-specific heel factors eliminates the costly installation of gas distri bution and measurement infrastructure.

Response 4.1.1-c: EPA thanks the commenters for their input. EPA is finalizing the requirement to use facility-wide gas-specific heel factors.

Comment Summary 4.1.1-d: One commenter (0108) suggested that EPA “...not mandate the development and use of site-specific and gas-specific cylinder heel factors for ‘relatively smaller’ semiconductor facilities. Rather, allow the optional use of 0.00 (0 percent) as the heel factor [i.e ., all of a cylinder’s gas is used, none returned to the supplier], and for ‘relatively smaller semiconduc tor facilities’ who may ultimately choose to install large numbers of cylinder scales to develop accurate cylinder heel factors, allow the use of the IPCC and industry-st andard cylinder heel factor of 0.10 (10 percent) through reporting year 2013 to spr ead the cost over th ree years.” TheNovember 2010 20 commenter noted that in order to comply with the proposed r equirements of the rule, it will have to purchase additional scales. These purchases would have to occur over a short timeframe, and the company has not budgeted for them. The commenter was therefore open to either opti on stated above, recognizing the first would overstate GHG

emissions.

Response 4.1.1-d: EPA does not agree with either of the commenter’s suggestions. Heels vary among gases and container sizes and shapes and so using either 0 or the

IPCC default heel factor will result in less a ccurate estimates of gas consumption and emissions. In addition, the use of heel factors that are specific to a facility will account for the differences in gas usage practices bet ween facilities. Use of the commenter’s suggestions would conflict with EPA’s intenti on to gather accurate facility-level

information

EPA understands that in normal facility operations, mass-based or pressure-based trigger points for change out are used to det ermine when gas cylinder/containers are to be changed. EPA anticipates that facilities should be able to implement practices in accordance with EPA’s heel factor requirement for the first year of data collection and reporting.

A facility may use Best Available Monitoring Methods (BAMM) for the first six months of the first data collection year without submitti ng a request to the Administrator. Under the BAMM provisions in the final rule for subpart I in §98.94(a), fa cilities must use the calculation methods prescribed by the rule , but BAMM is permitt ed for any parameter for which it is not reasonably feasible to acqu ire, install, or operat e a required piece of monitoring equipment in a facility or to pr ocure necessary monitoring services from providers. For more information on the us e of BAMM, please see the preamble section D, Electronics Manufacturing (subpart I), sect ion 1 (“Summary of the Final Rule”).

Comment Summary 4.1.1-e: One commenter (0131) stated that according to a 2009 International SEMA TECH Manufacturing Init iative (ISMI) survey, 80 percent of respondents currently estimate gas cons umption based on purchase records and an

assumed heel factor. Therefor e, the rule would require facilities to change their current practices to determine facility-wid e gas-specific heel factors.

Response 4.1.1-e: EPA thanks the commenter for its input. EPA understands that the requirement for facility-wide gas-specific hee l factors may require new practices to be instituted at electronics manufacturing fac ilities. However, EPA is finalizing the requirement for facilities to develop and use fa cility-wide gas-specific heel factors. EPA is not allowing facilities to use an assu med or default heel factor because heels may vary among gases and container sizes and s hapes. Therefore, applying a broad default or assumed value to every gas contai ner will lead to estimations that may not accurately represent the facility’s actual gas consumption, and hence the facility’s emissions. (See the Electronics Manufacture TSD available in the docket (EPA-HQOAR-2009-0927) for more details). See re sponse to comment 4.1.1-d for moreNovember 2010 21 discussion regarding why for faci lity-wide gas-specific heel fa ctors are required in the

final rule.

Comment Summary 4.1.1-f: One commenter (0131) provided the following response to EPA’s request for comment in a meet ing on May 19, 2010 on requiring the gas supplier to measure and track cyl inders: “While this may be pr actical at some facilities at additional cost, Semiconductors Industry A ssociation (SIA) believes this would not be practical in most cases. Specific ‘used’ cylinders may not be uniquely identified once they are removed from service such that th eir correlation of their incoming weight to their outgoing weight may not be possible. Furthermore, suppliers often pick up used cylinders from customers in multi-facility trip s, also known as ‘milk runs’. This would convolute the requirement to weigh specific cylinders for specific customers when they return to the supplier location. In any case, this would require the establishment of an ‘on and off’ facility tracking system for whic h facilities and supplie r protocols are not currently equipped or staffed. Most certainly all costs for this tracking would be incurred ultimately by the facility, thus avoiding no part of the cost and burden associated with gas usage tracking as proposed.”

Response 4.1.1-f: EPA thanks the commenter for this information. EPA has not modified the rule to require gas suppliers to measure and track cylinders. Please see the preamble section D, Elec tronics Manufacturing (subpart I) , section 1 (“Summary of the Final Rule”), for a summary of the gas consumption requirement s in the final rule.

Comment Summary 4.1.1-g: One commenter (0131) sugges ted that unless it is infeasible, facilities should develop a “heel factor specific to each type of cylinder and for each gas type based on the point establis hed as the trigger for changing out the cylinder.”

Response 4.1.1-g: EPA agrees that facilities should develop a heel factor specific to each type of cylinder and for each gas type based on the point established as the trigger for changing out the cylinder. EPA does not anticipate there would be any

circumstance in which this would be infeas ible for a facility. Therefore, EPA is maintaining the requirement that faciliti es must estimate gas consumption based on facility-wide gas-specific heel factors. S ee response to comment 4.1.1-a and 4.1.1-d for more discussion on the required gas cons umption methods using facility-wide gasspecific heel factors.

4.1.1.1 Accuracy and Precisi on of Measuring Instruments

Comment Summary 4.1.1.1-a: One commenter (0107) pres ented a technology that it believes can provide a cost-effective and e fficient measurement of a gas container’s heel with 1 percent accuracy or better. T he integrated pressure sensing technology

monitors the container’s contents with pressure transducing and active Radio Frequency Identification (RFID) technologies. The comment er requested confirmationNovember 2010 22 by EPA that the proposed technology satisfie s the requirements of the proposed rule and can be used for compliance with the final rule.

Response 4.1.1.1-a: EPA thanks the commenter for supplying this information about its technology. Provided that measurement instrumentation used by a facility to measure the residual weight or pressure of a cylinder, which in turn is used to determine facility-wide gas specific heel fact ors, meets the one per cent of full scale accuracy and precision requirement, the use of that instrumentation is permitted under

the rule.

Comment Summary 4.1.1.1-b: One commenter (0107) stated that according to its understanding, many electronics manufacturing fa cilities do not have the ability to meet the required precision requireme nts to measure gas containers heels. The commenter stated that it will be costly fo r many companies to install flowmeters in the timeframe required to prepare to comply with the rule.

Three other commenters ( 0099, 0112, and 0131) opposed the requirement that all instrumentation must have accuracy and precis ion of 1 percent full scale or better, citing in some cases the infeasibility to comply and the burden to obtain instrumentation to meet EPA’s requirement. One commenter (0112) asserted that a significant portion of its equipment has accuracies of 2 perc ent to 5 percent, while others can reach 1 percent accuracy. One commenter (0131) provided the following information: “The majority of new fabricators and new equipm ent will be able to meet the 1 percent requirement ... According to the 2010 Supple mental ISMI Survey, 74 percent of the respondents have measurement devices that meet the 1 percent accuracy/precision requirement while 26 percent may not. Of this 26 percent, the measurement devices used likely have an accuracy/precision in t he 2-4 percent range. This 26 percent of facilities can be expected to incur additional c apital costs to meet this instrumentation requirement.” The commenter (0131) also stated that no respondents utilize flow meters with an accuracy of 1 percent for tracki ng gas consumption. In order to meet the requirement, commenters asserted that they will have to in cur costs of purchasing and installing new equipment. The commenters proposed the use of a 5 percent accuracy requirement as provided in the general provisi ons of the Final MRR. In addition to the proposed 5 percent requirements; a commenter (0099) suggested that the performance

of the instrumentation would be verified us ing methods consist ent with an industry accepted practice at least annually.

Another commenter (0110) expr essed appreciation that the Ap ril 2010 proposed rule no longer included the requirement for flow meters and scales to be calibrated using

National Institute of Standards and Tec hnology (NIST)-traceable standards; however, the commenter is concerned that the 1 perc ent of full scale accuracy and precision requirement for instrumentation is still in cluded in the rule. The commenter asserted that a significant burden exists with li ttle environmental benefit in requiring

measurement devices with accura cies to 1 percent or less.November 2010 23 Response 4.1.1.1-b: EPA is not requiring the use of flowmeters to comply with gas consumption requirements of the final rule. The commenter (0107) may have misunderstood the proposed gas consum ption requirements, and this misunderstanding may have led it to make incorrect assumptions about the costs and technical challenges asso ciated with the rule.

Further, it is possible that some comm enters may have misunderstood the proposed precision and accuracy requirement. EPA proposed to require an accuracy and precision to be achieved on an instrument’s full scale basis, as opposed to the more stringent true value basis. In other word s, for a scale capable of measuring 300 pounds, regardless of the amount of gas bei ng weighed on the scale, the final rule requires that the measured we ight of gas must be accura te within +/- 3 pounds. Where as an accuracy based on the true weight of the gas in the cylinder would vary depending on the amount of gas in the cylinder.

EPA has concluded that it is feasible for facilities to comply with the accuracy and precision requirement to achieve +/-1 perce nt of full scale or better for measurement instrumentation as part of determining gas containers heels, and is therefore not modifying it as commenters suggested. As some of the commenters asserted (0112 and 0131), many facilities already will be able to meet the +/-1 percent of full scale or better accuracy and precision requirement. “A ccording to the 2010 supplemental ISMI survey, 74 percent of responde nts have measurement devices that meet the 1 percent accuracy/precision requirement while 26 percent may not.” 7 If a facility needs to procure new instrumentation that achieves 1 percent of full scale or better accuracy and precision, EPA believes there is suffi cient time to obtain the appropriate instrumentation. Further, EPA evaluated various types of scales that were available, and their ranges of achievable accuracy and precision. Through this evaluation EPA

concluded that instrumentat ion was available that meet s the accuracy and precision requirements.

EPA acknowledges that the general provisions of the Final MRR allows for different accuracy for measurement instrumentation. However, this requirement is not comparable to what is being required in subpart I. The subpart I accuracy and precision requirement to achieve one percent of full scale or better is consistent with some other subparts covering fluorinated GH Gs being finalized at this time. For example, subpart SS, which covers the m anufacture of electric transmission and distribution equipment, requires facilities to achieve the same 1 percent of full scale accuracy and precision. EPA has concluded gi ven the very high GWPs and often long atmospheric lifetimes of many fluorinat ed GHGs, it is important to gather gas consumption and hence emission information to a high degree of accuracy.

Comment Summary 4.1.1.1-c: One commenter (0089) stated, “While we understand the need to quantify this material accurately, we don’t believe the 1 percent requirement is achievable or necessary. Some of the cylinders containing covered materials may hold as little as ten pounds of material w hen full. The amount of material remaining

7 See EPA-HQ-OAR-2009-0927-0131.November 2010 24 when the cylinder is changed may be as little as one pound or less. Therefore, this would require ensuring that the residual mass may vary by no more than 0.01 lbs each time the cylinder is changed. Not only is such a small quantity insigni ficant in terms of total emissions, but it is doubtful equipment can be found that can consistently measure to this level. Many existing gas cabinet scales are maintained to an accuracy of 1 percent or even better at full scale. However, this same accuracy as a percent of mass will not be achieved when the cylinder is c onsumed all the way down to the residual heel and only a fraction of the initial mass re mains. Some very large containers are actually weighed with truck scales, which us ually have increments of 10 or 20 lbs. The same point is true when cylinders are monitored by pressure instead of mass. Commonly used pressure transducers are accu rate to 1 percent of full scale, or sometimes better. Again, this percent accuracy will not be achieved when only a

fraction of the full scale mass remains and it will not be possible to manage residual heels within 1 percent consistently. Intel s uggests that a more reasonable requirement is that cylinder changes be maintained within a limit of +/- 10 perc ent, or +/- 5 lbs. mass, whichever is higher.”

Response 4.1.1.1-c: It is possible that the comm enter may have misunderstood the proposed precision and accuracy requiremen t. The April 2010 proposed preamble states: “We are proposing that all flowmeters, weigh scales, pressure gauges, and thermometers used to measure quantities that are monitored or used in calculations in this proposal have an accuracy and precision of 1 percent of full scale or better .” (75 FR 18661, April 2010). In the final rule, EPA is requiring an accuracy and precision to be achieved on a full scale basis, as opposed to the more stringent true value basis, as the commenter described. Please see response to comments 4.1.1.1-b for information on the required accuracy and precision for meas urement instruments, and responses in

section 4.1.1.3 on heel factor recalculation requirements.

4.1.1.2 Exceptional Circumstance

Comment Summary 4.1.1.2-a: Five commenters (0099, 0110, 0112, 0123, and 0131) opposed the requirement to measure residual we ight and pressure of a gas container in an exceptional circumstance. One commenter (0112), who st ated that an exceptional circumstance is unlikely, proposed making measur ement optional. In this instance, the facility would decide whether the extra burden of tracki ng and measurement is worth the cost relative to any inaccuracy gained from over-estimating gas usage, and hence emissions. Two commenters (0110 and 0123) st ated that a difference of 20 percent from a trigger point may be in some case s such a small difference that it may be beyond the capacity of measurement equipmen t. These two commenters also stated that exceptional circumstances will happen so infrequently that not accounting for them

would have a minimal effect on overall r eporting accuracy and would not justify the increased tracking effort. Therefore, the two commenters suggested that the exceptional circumstance r equirement be eliminated. O ne commenter (0131) reported that only 6 percent of 1,000 cylinder changes in a typica l year would be considered to be under an exceptional circumstance. Two commenters (0099 and 0131) assertedNovember 2010 25 that the burden of additional manual tra cking of exceptional circumstance gas

containers would be unwarranted given the unlikely event of underreported gas usage.

One commenter (0131) presented the follo wing information: “The 2010 Supplemental ISMI Survey asked about exceptional circum stances for cylinder changes differing from the trigger point. Of the respondents, only one facility reported that because they currently track all cylinders, they could tr ack these exceptional cylinder changes. According to this company, however, ex ceptional cylinder changes occur very infrequently (facility reported 6 per cent or less). The typical reasons for changing out a cylinder at a different point are cust omer request and engin eering development activities. Given the sensitive nature of semiconductor processes, cylinders would rarely – if ever – be changed 20 percent past the trigger point by any facility; they would only be changed prematurely – or before t he trigger point had been reached. A facility can change out 1,000 or more cy linders of fluorinated GHG and N 2 O per year. Each cylinder changed out 20 percent prematurely w ould have to be specifically removed from the purchase record a ccounting and the calculation of Equation I-10, measured, and tracked manually. The burden of this i ndependent tracking is not warranted given that under-reporting of gas usage is highly unlikely.”

Response 4.1.1.2-a: EPA does not agree with the co mmenters’ assertions and suggestions. EPA appreciates the information provided by the commenter (0131) on one company’s actual experience with tracki ng exceptional circumstances, but EPA can

not make broad conclusions about the i ndustry based on one company’s experience. EPA is finalizing the requirement that wher e a container is changed in a exceptional circumstance (a point that di ffers by more than 20 percent from the trigger point for change out used to calculate the facility-wide gas-specific heel factor for that gas container type), rather than using a heel factor , a facility must weigh that container or measure the pressure of that c ontainer with a pressure gauge.

Given that facilities will have to track cy linders to some degree to adhere to other gas consumption requirements of the rule and that the o ccurrence of exceptional circumstances, as stated by commenters, is infrequent, quantifying the exceptional circumstance cylinders should not impose a high level of burden on facilities. Additionally, EPA does not agree that it should be optional to track exceptional circumstances because this may result in undesirable inconsistencies among methods facilities are using to estimate gas consumpt ion. It would be most beneficial to EPA to analyze emissions and trends using data and information that has been consistently developed (where feasible). The commenters who assert ed that a difference of 20 percent from a trigger point may be in some cases such a small difference that it may be beyond the capacity of m easurement equipment provi ded no supporting evidence of

this. For all of the aforementioned r easons, EPA is maintaining the exceptional circumstance requirement in the rule. It is a means to gather accurate facility-level information and should impose minimal burden on facilities because exceptional circumstances are infrequent.

In regards to the commenter who stated th at the under-reporting of gas usage is highly unlikely, EPA would like to clarify that the requirement to weigh or measure theNovember 2010 26 pressure of a cylinder that is changed in an exceptional circumstance applies not only to instances where a cylinder is changed 20 percent past a trigger point. The requirement applies to instances where a cyli nder is changed at any point that differs (over or under) by more than 20 percent from a trigger point for change out. A primary goal of this rule is to gather accurate (i.e ., neither under or over-reported) facility-level emissions. EPA has determined that this requir ement contributes to meeting that goal.

4.1.1.3 Recalculation of Facility- Wide Gas-Specific Heel Factors

Comment Summary 4.1.1.3-a: Five commenters (0089, 0099, 0112, 0123, and 0131) opposed the 1 percentage point threshold for recalculating heel factors. As an alternative, four commenters (0099, 0112, 0123, and 0131) recommended that heel factors should be recalculated if a trigger point for change out used to establish a heel factor differs by 5 percent or more of full weight or pressure or from the current trigger value. Another commenter (0089) suggested that cylinders be maintained at within a limit of +/- 10 percent or +/ - 5 lbs. mass, whichever is higher. One commenter (0112) noted that changes in the pr oduction process and experimentat ion often produce trigger changes of a few percent, but that a re calculation would be burdensome. The commenter explained, “The heel s that are returned to the manufacturer represent 4.3 percent of the total gas used. A 1 percent increase in the trig ger point will only represent an increase in usage (assuming the trigger point was reduced by 1 percent) of .4 percent, an extremely small number. Setting an adjustment fa ctor of 5 percent change in the trigger point ar guably will only increase use by 0.2 percent across the facility assuming that all chan ges increased the gas utilized fr om the cylinder. In fact, the majority of the trigger changes result in a decreas e in the gas used from the cylinder because of quality concerns generated by maximizing the use of gas in the cylinders.” Two commenter s (0099 and 0131) explained, “I n the course of minor operational modifications, a facility may adj ust a certain trigger point for a single cylinder or a small quantity of cylinders by a small amount to determine the effect on the process. This may be a temporary or permanent adjustment – and may only be for a small number of cylinders of that gas ty pe. In some of these instances, the percentage change from the original tr igger point may exceed the 1 percent requirement to recalculate, but may not result in any signif icant change in the amount of residual gas in the cylinder due to the amount of gas contained in the cylinder. A facility-wide gas-specific heel factor recalcul ation requirement of 5 percent of trigger point may be more reasonable and practica l and would likely be representative of any significant change. It would also reduce the burden of tracking multiple facility-wide gasspecific changes (and the intervals during which the change applied) that may only be temporary.”

Response 4.1.1.3-a: EPA has taken into consideration all the commenters’ concerns. In particular, EPA understands commenters’ concerns about the burden associated with tracking minor modifications to facilit y processes. EPA appreciates commenters’ various suggestions about how to modify t he heel factor recalcul ation requirement, and has decided to accept the suggestion to modify the requirement to be based on a 5 percent change in trigger point as opposed to the previously proposed 1 percent.November 2010 27 Specifically, in the final rule, EPA has finalized a provision which requires facilities to recalculate a facility-wide gas-specific heel factor if a trigger point for change out for a gas and container type differs by mo re than 5 percent from the pr eviously used trigger point for change out for the gas and container type. EPA has determined that this modification will help to balance the burden imposed on facilities with EPA’s goal of obtaining accurate, facility-level data. Requiri ng heel factor recalcul ation at a 5 percent change helps reduce burden by excluding re calculations for minor operational modifications that may be m ade to investigate process performance while it also captures any substantial changes in gas consumption practices.

Comment Summary 4.1.1.3-b: Two commenters (0110 and 0123) requested more specificity in the heel factor recalculati on requirement in order to better understand the meaning and benefit of it.

Response 4.1.1.3-b: In the final rule, EPA has clarified the language around the recalculation requirement to be tter articulate the requirement by making some editorial changes to the regulatory text. EPA is finalizing § 98.94 (b)(5) as follows:

You must re-calculate a facility-wide gas-s pecific heel factor if you use a trigger point for change out for a gas and container type that differs by more than 5 percent from the previous ly used trigger point for change out for that gas and container type.

EPA is finalizing the requirement for facilitie s to recalculate facility-wide gas specific

heel factors as a means for EPA to ensure that facilities are accurately estimating gas consumption even as faciliti es’ operations change over time. Please see response 4.1.1.3-a for a more detailed discussion regar ding the final requirements for heel factor

recalculation.

Comment Summary 4.1.1.3-c: One commenter (0095) reques ted guidance on how far back in time to go in order to recalculate a he el factor, if the heel fa ctor differs by more than 1 percent from the previous heel factor.

Response 4.1.1.3-c: Because EPA is requiring facilitie s to rely on facility-specific trigger point for change out for developi ng heel factors and because a change-out factor may be used provided it has not changed by more than 5 percent, there is no need to go back in time to recalculate a heel factor. Please see response to comment 4.1.1-b on the requirements for calculating heels factors.November 2010 28 4.1.2 Apportioning Gas Consumpti on to Process Categories with a Facility-Specific Engineering Model Based on an Activity

Indicator

Comment Summary 4.1.2-a: One commenter (0131) a sserted the following: “The results of the supplemental 2010 ISMI survey clearly indicate that using wafer pass as the required metric to apporti on gas usage is not appropriate for a variety of reasons.”

The commenter stated that fab tracking systems and tool recipe data based on wafer pass tracking are not readily available, and recipe mixes are very complex and dynamic, with different types and ranges of reci pes varying literally on a daily basis due to changes in production mix. The commenter asserted that “wafer pass, therefore, may not be viable as a required quantifiable indicator for all facilities. The ISMI

assessment of semiconductor facilities in t he United States has i ndicated that each facility is unique in terms of its wafer size , process technologies and product mix, gas distribution systems, and produc tion management systems. As such, there is no ‘one size fits all’ approach to apportion gas use and estimate perfluorocarbon (PFC) process emissions.” Two commenters (0099 and 0112) al so asserted that wafer passes was not feasible as a quantifiable indicator due to the complexity and variability of process recipes.

In a similar sentiment, another commenter (0110) asserted, “In the case of etch processes in particular, it is common to hav e an etch process start on one film type and

finish on a different film in the same wafer pass; i.e., oxide, nitride, polysilicon in a single wafer move. Etch recipes in particula r vary from part to par t and film type/stack, and are modified quite frequently , so re-establishing gas c onsumption for each new etch recipe would be burdensome. Over t he period of developmen t and production of a single part type, hundreds of unique reci pe changes are expected to occur.”

One commenter (0131) further proposed th e following: “Apportionment must occur based on at least one quantifiable indicato r and engineering judgment. A facility may determine the most appropriate indi cator based on its configuration and processes...Flexibility to choose indicators facility-by-facility by process category will provide more accurate esti mates now and the option to im plement improved methods later when new technologies develop.” T he commenter provided several example methodologies for apportioning gas consumption. In summary the commenter stated, “In all cases, the facility develops a lo cation-specific fluorinated GHG gas use monitoring and calculation plan detailing t he specific data collection processes, apportionment methodologies, and calculat ion and modeling processes used to determine actual facility gas use and emissi ons. The specific quantifiable indicators used should not be prescribed by this Rule.” Another commenter (009 9) also expressed

similar sentiments.

One commenter (0112) supported the “Ref ined Process” concept, but recommended a modified approach to apportioning gas c onsumption. The commenter argued that basing the method on wafer passes is not feasible and would cause a facility to have to make substantial investments in upfront and operating costs. T he commenter stated, “The proposal for apportioning fluorinated GHG (PFC) use across process types andNovember 2010 29 the number of proposed process categories d oes not take into account the limited capabilities of the majority of the U.S. semiconductor manufactu ring facilities to monitor, report, and segregate PFC gas use based on pr ocess data and wafer passes.” The commenter recognized that there is no one-size-fits-a ll approach to apportion gas usage but provides a detailed process by whic h it may occur at th eir facility. The commenter (0112) provided details on alte rnative apportioning methodologies for EPA to consider, but maintains that the best appr oach for apportioning gas consumptions is for a facility to develop site-specific methods.

Four commenters (0099, 0100, 0110, and 0131) pr esented similar sentiments that a facility should be permitted to use a Fa cility-Wide Apportioning Protocol based on appropriately selected quantifiable indicators fo r a facility’s process tool capabilities and configurations and engineer ing judgment. Two comment ers (0099 and 0131) asserted that most facilities will need to employ more than one quantifiable indicator in facilityspecific engineering models to accura tely apportion gas consumption. The

commenters also asserted that some fac ilities may already have facility management software which obtains process and tool information that may be used in models to apportion gas consumption.

Response 4.1.2-a: EPA understands commenters’ concer ns with the proposed method to apportion gas consumption based on wafer pass and is sensitive to the burden and the potential limitations on oper ational flexibility this may have on facilities. EPA has therefore modified the gas appor tioning requirements for the final rule (see §98.94(c)).

EPA will permit the use of fac ility-specific engineering m odels based on a quantifiable metric selected by the facility (such as wa fer passes or wafer starts) to apportion gas consumption. In the final rule, facilities are required to develop an engineering model that utilizes measurable process information to develop apportioning factors. EPA does not specify the quantifiable me tric that must be used in these models; rather, EPA is allowing reporters the flexibi lity to select the most appr opriate quantifiable metric on which to base the facility-specific engi neering model, provided model documentation and verification requirements are met. EPA has concluded that the gas apportioning methods provided in the final rule shoul d accommodate approaches suggested by the commenter. See the preamble section D, El ectronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for a more detailed response to comments on apportioning gas consumption.

Comment Summary 4.1.2-b: One commenter (0122) stated that they employ the IPCC Tier 2b methods in their emissions reporting for their operations in Europe. In this regard, the commenter noted that they routinely tra ck PFC use for CVD chamber cleaning (using in-situ NF 3 cleaning, coupled with POU abatement) and etch processes (also coupled with POU abatement) based on c onfigurations of equipment at the facility. However, the comm enter stated that there is no mechanism to apportion PFC use and emissions to specific etch subcategories because it would be very difficult to collect such data and match it to specific calculation of PFC gas consumption.November 2010 30 Response 4.1.2-b: EPA does not agree with the commenter that it is too difficult to

calculate emissions from more than one br oad etch category. EPA has concluded that it is feasible for facilities to apportion gas consumption to more t han just two broad etch and clean categories using the methods EPA has prescribed in the final rule. EPA

understands that while some semiconductor facilities may not already have the necessary mechanisms in place to track and record the necessa ry information to apportion gas consumption, in the final ru le, EPA is permitting a method that allows facilities to select and use the quantifiable metric that works best for a particular facility.

Wafer pass counts in modern fabs, for ex ample, may be available through the manufacturing execution softwar e (MES) that comes with process equipment. MES is capable of tracking the activities asso ciated with each piece of manufacturing equipment. In older fabs that may not empl oy MES, wafer pass counts are available through process flow information for each product manufactured. While wafer pass count information is available, EPA understands that it may not be routinely gathered for gas apportioning purposes. Instead, it may be gathered at the request of facility and product line managers for purposes of managi ng work in process load, reducing fab cycle time, reducing product cycle time, ident ifying and removing process bottlenecks, etc. For estimating gas us age, it appears wafer pass count s would be collected either electronically or physically and used to develop the apportioning model. For an expanded explanation of this example, please see the Electronics Manufacturing TSD

available in the docket (EPA-HQ-OAR-2009-0927).

EPA understands that facilities may incur a cost to implement the mechanism necessary to track and record already existing quantifiable metrics, such as wafer pass or wafer starts, to apportion gas consumptio n; however, EPA has made efforts in the final rule to balance the burden imposed on facilities with EPA’s goal of obtaining accurate, facility-level data. EPA has a ccounted for such costs in the Economic Impact Analysis (see sections 4 & 5 of the Econom ic Impact Analysis available in the docket, EPA-OAR-2009-0927).

Please see the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Responses to Comments and Responses”), for the response to comments on apportioning gas co nsumption. Please also see response to comment 4.1.2-a for apportioning gas consumption using facility- specific engineering models based on quantifiable metrics

Comment Summary 4.1.2-c: One commenter (0110) ques tioned EPA’s statement in the proposal that engineering judgment was not acceptable in estimating apportioned gas usage. The commenter stated that at it s facilities, engineering judgment and other factors are used for air toxics and priority pollutants to fulf ill other regulatory requirements (e.g., reporting of annual emissions of criteria pollutants and hazardous air pollutants), and the commenter question ed why engineering judgm ent is not also acceptable for apportioning in the GHG MRR.November 2010 31 Response 4.1.2-c: While EPA is not opining on the requirements of other regulatory programs, in contrast to t hose requirements that generally focus on whether a facility’s emissions are below a specifi ed limit, this rule focuses on establishing each facility’s annual GHG emissions in tons per year. For this reason, EPA is finalizing certain requirements in this rule to ensure that EPA receives accurate facility-level emissions

data.

EPA is not allowing the use of “engineeri ng judgment” to develop apportioning factors because, unlike quantifiable metrics, enginee ring judgment is subjective and could cause apportioning factors to vary. This pres ents an issue for multiple reasons. First, without the use of a quantifiable metric on which to base gas apportioning factors, it is not possible for EPA to verify the method by which gas consumption is apportioned to process recipes, sub-types, or types. EPA must be able to verify the data being used to calculate emissions. Second, engineering judgment is not a lways accurate, precise, or repeatable. Third, changes in staff res ponsible for developing apportioning factors (e.g., staff turnover, staff reassignments, changes in priori ties, or some combination thereof within a facility) may lead to unintended variations in gas consumption calculations, and hence emission estimates.

As a result, the use of engi neering judgment to apportion gas consumption to process recipes, sub-types, or types, as opposed to the use of an engineering model based on a quantifiable metric, would lead to increased unc ertainty in reported emissions. EPA is permitting the use of considerable engineering knowledge in the design of a facility’s apportionment model because the quality of that knowledge wi ll be tested based on empirical data via the requir ed performance verification of the model. An engineering model that apportions gas consum ption based on tool-specific activity records or logs is preferred to engineering j udgment based on general technica l knowledge of processes utilized at a facility because tool-specific activi ty is quantifiable. Please see response to

comment 4.1.2-a for additional details on the methodology in the final rule for apportioning gas consumption using facility- specific engineering models based on quantifiable metrics.

Comment Summary 4.1.2-d: One commenter (0089) expre ssed its support of the use of facility-specific engineering models to apportion gas consumption, and asserted that the way the rule was proposed prohibits t he use of some valid approaches. The

commenter noted that a 2006 IPCC Tier 3 Method (Tier 3) is used at its facility in which gas usage is measured at a broader fa cility level and then apportioned down appropriately based on knowledge of proces s recipes. Specifically, the commenter stated, “The actual apportionm ent quantifying the portion of material used in a given group of process steps is estimated based on knowledge of the proc ess recipe. Intel’s factories typically manufacture one or two di fferent product lines, each of which has a tightly defined set of process steps required, and a recipe for each of these steps that specifies the amount of chemical used. T he factories also track the number of wafer starts of each different process the facilit y is running. The recipe information detailing

the use breakdown is combined with the number of wafer star ts for each process run to develop an overall estimate of material used on different process steps. While theNovember 2010 32 number of wafer passes is a factor in deter mining the amount of c hemical an operation uses, it is not an indicator that is ultimate ly tracked. This method definitely relies on some quantifiable indicators such as total fab gas usage and total wafers manufactured. However, the apportioning of gas among process steps also involves some engineering judgment. The gas use in those individual steps is not actually measured, but is assumed to be proportional to the amounts specified in the process recipes.” The commenter s uggested that the use of kno wledge of process operations gas consumption should be allowed, even where that use is not spec ifically measured

at the tool level.

Response 4.1.2-d: In the proposed rule, EPA would have required facilities to use wafer pass as the quantifiable indicator with which to apportion the facility’s gas consumption. At the time the rule wa s proposed, the information available to EPA about methods to apportion gas consumption was limited. To this end, in that proposal, EPA also stated that it recogni zed that facilities may use other types of quantifiable indicators of gas-usage activity to devel op facility-specific engineering models to estimate gas consumption, and request ed information about other quantifiable

indicators.

It is unclear how the commenters specific suggestions to allow for the use of both knowledge of process oper ations and engineering j udgment as a means for apportioning gas usage would actually be im plemented in that is unclear what quantitative information would be tracked or m easured and used. Therefore it is not feasible for EPA to finalize the suggested method in the rule. However, based on this comment, other information received in th e public comment period, and additional analyses, EPA has modified the gas apportioning requirements in the final rule to provide more flexibility. In the final rule, a facility has the option to choose the quantifiable metric from whic h to base their facility-spec ific gas apportioning model provided the facility documents and verifi es the model. The method for gas apportioning in the final rule will ensure t hat facility-specific models result in apportioning factors that are precise and accurate. Please see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the response to comments on apportioning gas consumption. Please also see response to comment 4.1.2-a for additional details on the methodology in the final rule for apportioning gas consumption us ing facility-specific engineering models based on quantifiabl e metrics.

Comment Summary 4.1.2-e: One commenter (0095) asserted that for a semiconductor R&D facility, it will be diffi cult to apportion gas consumption for the Refined Method because one bulk cylinder may support multiple ch ambers of process tools on which multiple refined process cat egories may be run. The commenter stated that determining the amount of gas fed into each process ca tegory is therefore difficult because gas utilization varies between chambers depending on business needs, customer demands, and concept and feasib ility studies for new processes.November 2010 33 Response 4.1.2-e: EPA is clarifying in the final rule that if a facility engages in R&D activities, they are not required to report t he emissions from that activity. Please see response to comment 1-b for a more deta iled discussion on the exemption for R&D activities. Please also see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Re sponses”), for the response to comments on apportioning gas consumption.

Comment Summary 4.1.2-f : One commenter (0110) stated that while it meters gas that is going to processes using mass flow c ontrollers (MFCs), their current operations do not log and record flow data. The comment er asserted that to log and record this

data would be burdensome.

Response 4.1.2-f: Although facilities may utilize flow meters to apportion gas consumption, EPA is not requiring gas c onsumption to be apportioned based on information gathered from flow meters. In the fi nal rule, EPA has provided a flexible method for facilities to develop apportioning fa ctors. These flexible requirements are

intended to reduce the burden associated with apportioning gas consumption that more stringent requirements, such requiring the measurement of mass flow of gases using mass flow meters, may impose.

Please see response to comment 4.1.2-a for additional details on the methodology for apportioning gas consumption finalized in the rule. Please also see also the preamble section D, Electronics Manufacturing (subpa rt I), section 3 (“S ummary of Comments and Responses”), for additional res ponse to comments on apportioning gas consumption.

4.2 Emission Estimation Methods for Semiconductor Facilities

Comment Summary 4.2-a: One commenter (0122) st ated that semiconductor manufacturing processes change frequently, with ongoing improvem ents to current methodologies requiring installation of new or modified equipment on a regular basis.

The commenter further stated t hat larger-scale migrations to the next “technology node”- representing the ever-smaller features created on the silicon wafer—typically happen as often as every two years. The commenter asserted that when EPA postponed finalizing the electronics portion of the GHG Reporting Rule, the Agency recognized the difficulties and complexities inherent in estimating emissions in the semiconductor manufacturing sector. T he commenter further stated, “There are currently no agreed-upon methods for quantif ying and reporting PFC emissions from

semiconductor and other electronics facilitie s, other than those developed under the

IPCC.”

Response 4.2-a: EPA’s goal for this rule differs from the goal of the IPCC 2006 Guidelines. EPA's goal for this rule is to require facilities to report as accurate as practical, facility-level emissions, while the IPCC methods are intended for voluntary reporting of country-level emissions inventor ies. In addition, since the IPCC methods were developed (based on information collect ed prior to 2006), the industry has movedNovember 2010 34 from manufacturing 200 mm to 300 mm substrates (with higher gas flows), has reduced feature size 3-fold with a corresponding 20 percent increase in number of levels manufactured (resulting in more etch ing and chamber cleaning), and adopted new etching and chamber cl eaning methods to achieve the required technical and economic performance (requiring the use of updated emission factors).

The emissions estimation methods for electr onics manufacturing facilities required in the final rule may be viewed generally as an extension from and building upon the IPCC’s methods; however EPA’s required met hods are more distinct in terms of applicability and level of deta il. EPA has improved upon the IPCC methods in several ways. First, the number of emitting ca tegories (process types/sub-types) has been expanded from the IPCC methods. Second, the emission factors in the final rule have been updated, to the extent po ssible based on information available to EPA, from the IPCC Tier 2b factors. Third, EPA has al so finalized methods for estimating gas consumption in this rule that are im provements over the IPCC gas consumption estimation methods (e.g., the use of facility- wide, gas specific heel factors, as opposed to a default factor – see section 4.1.1). And lastly, EPA has also made improvements over the IPCC methods in regards to a ccounting for controlled emissions; the IPCC

methods utilized a default DRE that was based on anecdotal information rather than the direct in-fab measurements EPA used to develop its default value for DRE (see section 5.2). These updates and im provements in emission estimation methods, moving

forward from the IPCC methods , are crucial for gathering accurate facility-specific emissions data in an industry that is const antly evolving, and will enable EPA to collect data for use in developing future GHG policies and programs.

Please see response to comments 4.2.3-a and b for more discussion on why EPA is not finalizing the Tier 2b for semiconductor m anufacturing facilities. Please also see the preamble section D, Elec tronics Manufacturing (subpart I) , section 3 (“Summary of Comments and Responses”), for a more det ailed response to comments on emission

estimation methods for semiconductor fac ilities and apportioning gas consumption.

4.2.1 Refined Method

Comment Summary 4.2.1-a: One commenter (0122) stated t hat it is highly uncertain

whether the Refined Method would actual ly reduce uncertainty in emissions calculations. The commenter also argued t hat because a mature foundry fab requires the use of a variety of process flows and va rying recipes to be run at any one time, the complexity and cost associated with t he Refined Method is not warranted. One commenter (0110) suggested that the goal of the proposed Refined Method is good, but that it does not accomplish its goal and imposes a significantly greater burden on industry. The commenter also asserted that any increase in accuracy from using the Refined Method in comparison to the Tier 2b method is minimal. Two commenters (0099 and 0131) stated that the Refined Method stems from a deeply flawed uncertainty analysis and misunderstandings or incorrect assumptions of current industry processes. The commenters asserted that the Refined Method would result in significant capital and ongoing compliance costs. One commenter ( 0099) also stated that “It [the Refined Method] would not achieve EPA’s stated objective to obtainNovember 2010 35 ‘information...relevant to implementing the existing CAA’ that ‘produces a more representative and accurate emissions esti mate’ (75 FR 18655 and 18663, April 2010).” The commenter argued that fu rther data collection under the Refined Method should not be pursued.

Another commenter (0108) stated that it does not have t he necessary data available to comply with the Refined Method, and t hat compliance would be unnecessarily burdensome. The commenter also express ed concern that the Refined Method would

not lead to accurate results. The commenter stated that, “In the very early 1990’s when crafting Microchip’s emissions profiles fo r its first (Tempe Fab 2) air permit we attempted to use a process gas flow reci pe-based methodology to estimate gas usage tool by tool and per wafer. The result significantly underestimated overall gas usage compared to the quantity issued from raw ma terial stockrooms because gases flowed for a variety of calibration and maintenanc e procedures where wafers were not processed; gas flow rate and duration for th ese procedures were not consistent over time. The recipe did not adequately characterize total gas usage. Only a per-gas inventory-based approach was accurate.”

Response 4.2.1-a: It is unclear how the commenter (0108) implemented a method to use a process gas flow recipe-based methodolog y to estimate gas usage tool by tool and per wafer because the commenter did not provide any supporting or detailed

information. It is also not clear how the commenter quantified “significantly underestimated gas usage,” or how the commenter arrived at this conclusion. Based on the limited information the commenter prov ided pertaining to their experience in using a process gas flow recipe-based methodology to estimate gas usage, at this time EPA can not compare the method the comment er attempted to use, and the methods EPA is requiring to apportion gas consumption in the final rule. As such, EPA can also

not draw inferences about the robustness or accuracy of the me thod described. Please see section 4.1.2 and the preamble se ction 3 (“Summary of Comments and Responses”), for a more detailed re sponse to comments on apportioning gas consumption.

Please see the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Comments and Re sponses”), for a more deta iled response to comments

on emission estimation methods for se miconductor facilities and apportioning gas consumption. Please also see sections 8 and 10 for more information on the costs

associated with the rule and the uncertain ty associated with the Refined Method, respectively.

Comment Summary 4.2.1-b: One commenter (TRANS-DC- 03) noted their shared interest with EPA in accurate, reliabl e data, and system-wide accuracy. The commenter encouraged EPA to ensure that the Refined Method does indeed provide

accurate data.

Response 4.2.1-b: EPA has determined that the methods provided in the final rule effectively balance EPA’s objectives of obtai ning accurate, facility-level data againstNovember 2010 36 burden to industry. Please see response to comment 4.2.1-a on the Refined Method and the preamble section D, Electroni cs Manufacturing (subpart I), section 3 (“Summary of Comments and Re sponses”), for a more deta iled response to comments

on emission estimation methods fo r semiconductor facilities.

4.2.1.1 Other Methods of Categorizing Processes

Comment Summary 4.2.1.1-a: One commenter (0112) responded to EPA’s request for

comment on the use of feat ure-based or filmed-based appor tioning instead of processtype categories and asserted that categorization by etch type is the most effective approach as multiple categories fo r etch processes are developed.

Response 4.2.1.1-a: EPA appreciates the commenter’s i nput. However, in the final rule, EPA is not requiring a method to es timate emissions for semiconductor manufacturers that is based on plasma etch ing sub-types (please see response to comment 4.2.1-a).

It is unclear what the commenter’s preference fo r “etch type” is referri ng to, that is, it is unclear if the commenter is associating et ch-type with either f ilm-based or featurebased etching sub-types. Nonetheless the met hods EPA has included in the final rule are not based on etching sub-types in this rule. However, EPA maintains that estimating emissions based on process sub-types for etch with robust default emission

factors would result in more accurate fac ility-level emission estimates as compared to estimating emissions using a single broad et ch process type. This is because the variability in processes would be captured with more granular etch process sub-types. In future years EPA may evaluate the recipe- specific emission factors received through

the final rule to determine whether a sufficie ntly robust data set exists to establish default emission factors for process sub-types for plasma etching. In the future, EPA may consider requiring the semiconductor fa cilities that will be us ing a default emission factor for the etch process type under the final rule to estimate and report emissions using an approach based on multiple et ch and chamber clean process sub-types similar to the Refined Method EPA proposed in April 2010.

At this time, EPA does not have enough data and information to determine if etch subtypes established in the future would be feat ure-based or film-based. For this reason, in the final rule, EPA is requiring facilities that develop recipe-specific emission factors for etch recipes to identify these factors by both the film and subs trate that was etched and the feature type that wa s produced. EPA plans to consider such information

received as a result of this final rule in potential future actions.

4.2.1.2 Draft Default Emissions Fact ors for Refined Process Categories

Comment Summary 4.2.1.2-a: Two commenters (0099 and 0131) noted that “emission factor coverage on the multiple etch categories is inadequate and data quality is not sufficient to support the differ entiation of etch processes into multipleNovember 2010 37 categories...The overarching issue is t hat both the number and accuracy of the

available etch emissions factors is not adequate to support refine ment of the etch category for this rule.”

Response 4.2.1.2-a: EPA agrees with commenters that t he available data at the time of the proposal was insufficient to support es tablishing default emission factors for etch process sub-types. EPA did not receiv e enough additional data during the comment period to address this insufficiency. 8 Accordingly, EPA is finalizing provisions in the

rule that do not establish default emissions factors for etch sub-types. EPA can not make any assertions about the quality of the data at this time given limited information,

and the commenter who noted that the data quality was not su fficient did not provide information supporting their claim. Pleas e see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the response to comments on emission estimati on methods for semiconductor facilities.

Comment Summary 4.2.1.2-b: One commenter (0131) reques ted to be provided with the background data used to generate the Refined Method emission factors.

Response 4.2.1.2-b : EPA made available to the public all of the underlying data used to generate the Refined Method emission factors in Table 5 of the report Draft Emission

Factors for Refined Semiconductor Manufacturing Process Categories(EPA-HQ-OAR2009-0927-0073). In the aforementioned repor t, EPA was also transparent about the details on the methods and assumptions that were used when developing the proposed

Refined Method emission factors.

Comment Summary 4.2.1.2-c: One commenter (0110) noted a lack of understanding between EPA and industry regardi ng the availability of emi ssion factor data to support

the Refined Method. Two other commenters (0099 and 0131) asserted that for the majority of GHG usage (72 percent), t he emission factors are unchanged compared to

the Tier 2b emission factors. The commenters asserted that this highlights the appropriateness of using the Tier 2b factors at this point in time. One of the commenters (0131) also supported the use of t he Tier 2b emission fa ctors by stating, “The 2006 IPCC Tier 2b methodology is a gl obally accepted method for estimating

GHG emissions for a semicondu ctor manufacturing facility. The Tier 2b factors were developed using 190 distinct measured emission factors for CVD chamber cleaning and etch processes and are accurate for dev eloping an inventory of GHG emissions.” 9,10

8 In its proposed rule (75 FR 18652, April 2010) , EPA published a range of values for each emission factor for the nine proposed proc ess categories. EPA proposed a r ange of values because it had not received sufficient data to select a specific value within each range. Based on additional information received after publication of the proposed rule, EPA pub lished a Notice of Data Availability where it made available to the public draft default emission factor s for semiconductor manufacturing refined process categories (75 FR 26904, May 2010). As of publication of the final ru le, EPA has not received additional data (i.e., utilization and by-p roduct formation rates).

9 This commenter supported the use of a mix of t he IPCC Tier 2b factors and EPA NODA factors for the

“Alternative Refined Method.”November 2010 38 Response 4.2.1.2-c: Based on industry public st atements, EPA understood that equipment manufacturers were measuring emi ssions and emission factors by virtue of device manufacturer equipment purchase r equirements, augmented by ISMI Guidelines for Emissions Characterization. EPA learned, however, through the development of its Notice of Data Availability; Default Emi ssion Factors for Semiconductor Manufacturing Refined Process Categories, May 2010 (NODA) that this was not the case, and that few

additional emission factor measurements had been made (since the start of the 2006 IPCC process in 2004) by eit her equipment manufacturers or device manufacturers.

In light of the lack of available data fo r some categories, EPA has not established

emission factors for all of the proposed Refined Method pr ocess categories. Although EPA agrees that many of t he emission factors proposed for the Refined Method in the May 2010 NODA have not substantially cha nged from the IPCC Tier 2b factors, EPA has published default emission factors that improve upon the IPCC Tier 2b factors because they reflect a more recent and robus t set of data. Please see response to comment 4.2.3-a and b on why EPA is not finalizing the Tier 2b method for semiconductor manufacturing facilities.

EPA used industry data provided in cooper ation with Semiconductor Equipment and Materials International to develop the published factors in the May 2010 NODA. 11 The data EPA received were data that had been prev iously used to establish the 2006 IPCC emission factors, as well as additional and more recent emission factor data that were not available during the 2006 IPCC factor development. Because the data set EPA used to develop the emission factors presen ted in the May 2010 NODA is more robust, EPA elected to publish updated default factors using the data presented in the May 2010 NODA as opposed to allowing the us e of the IPCC Tier 2b factors.

Comment Summary 4.2.1.2-d: Two commenters (0099, 0131) noted that an emission factor development process similar to the AP- 42 process could be utilized in the future

if EPA wants to establish revised emissi on factors and improve the accuracy of the data. As an alternative, the commenter s also suggested that EPA and industry engage in a memorandum of understanding (MOU) “to develop and execute a voluntary, cooperative plan...to develop emissions factor s, with defined uncert ainties, to model and determine the degree of refi nement that can be achieved in the uncertainty of the

emissions calculations.” O ne commenter (0131) also stated, “...it is not appropriate to

include such emission factors in the text of the Re-Proposed Rule it self, since modifying or adding new emission factors as new tools and processes are adopted, or as emissions factors for existing tools are refined, would be hampered by the formal rulemaking that would be required to modify the text of the Rule. Moreover, the short period of time between the Rule proposal and finalization simply does not provide sufficient opportunity to develop appropriate emission factors.”

10 This commenter supported the use of a mix of t he IPCC Tier 2b factors and EPA NODA factors for the

“Alternative Refined Method.”

11 See Appendix C of the Electronics Manufactur e TSD (Mar. 22, 2010) and the May 2010 NODA and accompanying report for more details.November 2010 39 Response 4.2.1.2-d: EPA appreciates the industry’s o ffer to work with EPA to develop emission factors; however, in general, EPA disagrees with commenters’ suggestions. While EPA is not ruling out the possibility of using the AP-42 process as a means to update emission factors for electronics manufact uring in the future, EPA is not finalizing such a process at this time. EPA has determined that at this time it is most appropriate to develop and update emission factors for electronics manufacturing through the Mandatory Reporting Rule regula tory framework. The objec tive of the Mandatory GHG Reporting Program is to obtai n facility-specific data to use in developing future GHG policies and programs. To serve its int ended purpose, EPA believes that the data must be collected according to consistent methodol ogies that are prescribed in the rule.

Similarly, EPA is not ruling out the possibi lity of engaging with the industry to develop

emission factors for electronics manufactu ring through an MOU. However, for purposes of meeting EPA’s goals for this ru le, EPA has determined that it is most appropriate to develop and update emission factors for electronics manufacturing through a regulatory framework where fac ilities are required to use consistent methodologies.

Please also see the preamble to the Final Rule for additional discussion on how the GHG Reporting Program relates to EPA and U.S. government climate change efforts and to other State and Regi onal Programs (74 FR 56265- 56266, October 2009). In addition, please refer to the preamble to the proposed rule on Mandatory Reporting of

Greenhouse Gases: Additional Sources of Fluorinated GHGs (75 FR 18655, April 2010).

4.2.1.2.1 Frequency a nd Process of Updates

Comment Summary 4.2.1.2.1-a: One commenter (0128), who supported the adoption of the Tier 3 method, in sists that EPA commit to fr equently reviewing and updating default factors if EPA continues to rely on le ss accurate default emission factors. The commenter acknowledged the release of t he draft emission factors published in EPA’s NODA. The commenter encouraged EPA to ma ke all of the data underlying the emission factors available to the public for independent verification and review of the

data and emission factors.

Response 4.2.1.2.1-a: EPA believes that, where feasible, it is important to provide the public with an opportunity to review the underlying data that EPA uses to develop

emission factors. All of the underlying data that was used to establish the default emission factors published in the final rule for semiconductor manufacturing were made available to the public in Table 5 of t he report to the May 2010 NODA (Draft Emission

Factors for Refined Semiconductor Manufac turing Process Categories, EPA-HQ-OAR2009-0927-0073). Please see the Electronics Manufacture TSD (Mar. 22, 2010) for

more details on how the data was obtained.November 2010 40 In addition, in future years, EPA may eval uate the recipe-specific emission factors received through this final rule to determine whether a sufficiently robust data set exists to establish default emission factors for pl asma etching process sub-types. In the future, EPA may consider requiring the se miconductor facilities that will be using a

default emission factor for the etch process type under this final rule to estimate and report emissions using an approach based on mu ltiple etch and chamber clean process sub-types similar to the Refined Method EPA proposed in April 2010.

4.2.2 IPCC Tier 3 Method

Comment Summary 4.2.2-a: One commenter (0089) asserted that the final rule should

make clear that facilities t hat use Tier 3 methods are not required to report emissions under the process categories as proposed, but that instead they will be able to use the process steps defined at that facility.

Response 4.2.2-a: In the final rule, EPA is not requiri ng that emissions estimated using

the Tier 3 method be reported under specific process sub-types.

It is unclear how the commenter is defining a process step, however in the final rule, the Tier 3 method consists of calculating and reporting emissions using recipe-specific emission factors for all production processes that use fluorinated GHGs. As required in the final rule, emission factors must be dev eloped for each individual recipe or set of similar recipes used at a facility and emissi ons must be calculated and reported for each recipe (including those in a set of simila r recipes) using the reci pe-specific factors. Facilities must then aggregate emissions calcul ated for each individual recipe or set of similar recipes for each of three process ty pes defined by the rule– plasma etching, chamber cleaning, and wafer cleaning.

4.2.2.1 300 mm and Smaller Wafer Technologies

Comment Summary 4.2.2.1-a: One commenter (0131) did not support requiring the use of IPCC Tier 3 methodology. The comm enter, who supported t he use of the Tier 2b emission factors (see comment summary 4.2. 1.2-c), asserted that most facilities do not use a Tier 3 method, and t herefore there is a limited data set that is representative of manufacturing conditions on which to bas e the assertion that the Tier 3 method results in improved accuracy of emission estimates.

Response 4.2.2.1-a: While EPA is not requiring semi conductor manufacturing facilities manufacturing wafers 300 mm or smaller to estimate emissions from all production processes that use fluorinated GHGs using re cipe-specific emission factors because it is mindful of the burden this may impose, EPA continues to maintain that the Tier 3

method will result in the most accurate fa cility-specific emission estimates. For example, the IPCC 2006 Guidelines state “When using Tier 3 method for

semiconductor and TFT-FPD manuf acturing, the resulting es timates of emissions will be more accurate than the Tier 2a, 2b or Tier 1 methods, on the order of ± 30 percent (95 percent confidence interval).” T he IPCC 2006 Guidelines are a consensusNovember 2010 41 document, and were prepared with substant ial input from and agreement among industry experts. To balance burden and the need fo r accurate facility level data in the final rule, EPA is requiring only semiconductor manufacturing facilities that manufacture wafers that are 300 mm or smaller, to calc ulate and report their et ch process emissions using directly measured recipe-spec ific emission fact ors.

Because EPA does not want to prohibit facilitie s from gathering more accurate data, the final rule allows any semiconductor manufac turing facility that manufacturers wafers

that are 300 mm or smaller to use the Tier 3 method to estimate and report emissions for all processes that use fl uorinated GHGs if they elect to do so (see §98.93(a)(3)).

Please see the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Comments and Re sponses”), for the response to comments on emission

estimation methods for semiconductor facilities.

Comment Summary 4.2.2.1-b: One commenter (0110) st ated that it had not determined any emission factor s through testing, and that bas ed on their review of the record and the SIA/ISMI Facility results pr esented to EPA, only one company in the US estimates emissions using a Tier 3 methodology . The commenter furt her stated that it received limited information from their equip ment supplier in regards to developing

emission factors. The co mmenter noted that one major U.S. equipment supplier had provided the company with over ten emission characterization reports based on one recipe. The commenter stated, “In light of the uncertainties of EPA’s proposal and the enormous complexity of our facilities, however , it isn’t clear how this information would be utilized to develop factors if we were r equired to do so for hundreds of recipes in multiple facilities across an entire company .” The commenter argued that given the challenges involved in obtaining site-specific data for such complex facilities and that the Tier 2b average emission factors establis hed by the IPCC are conservative, the Tier

2b factors should be allowed for large facilities.

Response 4.2.2.1-b: EPA does not agree with the comm enter that semiconductor manufacturing facilities should be allowed to estimate and report emissions using the

2006 IPCC Tier 2b method. While the 2006 IPCC Guidelines are a consensus document, and were prepared with substant ial input from and agreement among industry experts, the Guidelines were prepar ed with the intention of serving national GHG emissions inventorying purposes. The Tier 3 method requires facility-specific emission information; however other methods such as the Tier 2b method do not. The Guidelines specifically stat e that the IPCC Tier 2b factors presented were “developed specifically for this guidance.” In using t he IPCC Tier 2b factors in a facility-level emission estimation method uncertainty asse ssment, EPA found that the IPCC Tier 2b factors are likely to understate facility emissions, not result in conservative emission estimates (see the Electronics Manufacture TS D, Appendix C for more details) as the

commenter asserted. Further , because the IPCC Tier 2b factors are simple averages,

EPA has no basis on which to infer that the IPCC Tier 2b fact ors would overstate

emissions.November 2010 42 EPA acknowledges that at this time , semiconductor fac ilities may not have characterized emissions from all production processes that use fluorinated GHGs. To this end, EPA has structured the final rule to minimize the burden imposed on facilities in conducting direct measurements. For example, EPA is requiring only direct measurement for the etching process type. In addition, EPA is requiring only the largest facilities to estimate and report t heir etch emissions using recipe-specific emission factors. Lastly, EPA is allowing any factors that were developed for one individual recipe to be applied to similar recipes (as defined in the final rule).

In the final rule, EPA has specified that w hen reporting recipe-specific emission factors, reporters must identify the f ilm or substrate that was et ched/cleaned and the feature type that was etched. Reporting emission fa ctors in this manner will give EPA the opportunity to evaluate various options for de veloping default emissi on factors for future

use.

It is important to note that in the final rule facilities are allowed to use BAMM for the first six months of data collection for any param eter, such as recipe-specific emission factors, for which it is not reasonably feasible to acquire, install, or operate a required piece of monitoring equipment or to pr ocure necessary measurement services. Facilities are also given the opportunity to apply for extensions for the use of BAMM through the full first year of data collecti on. Please see the preamble section D, Electronics Manufacturing (subpart I), section 1 (“Sum mary of the Final Rule”) for more information on the BAMM provisions for elec tronics manufacturing facilities. Please also see the preamble section D, Electr onics Manufacturing (s ubpart I), section 3 (“Summary of Comments and Re sponses”), for a more deta iled response to comments

on emission estimation methods.

Comment Summary 4.2.2.1-c: One commenter (0128) was concerned that switching

from the Tier 3 method to the Refined Method will result in less accurate emissions data for cleaning and etching in semiconductor facilities. The commenter stated, “We encourage EPA to require Tier 3 reporting for these processes given the need for accurate data and the significant emissions from this sector. The Tier 3 approach relies on facility-specific emissions data on gas consumption, gas utilization, by-product formation, and DRE rather t han default emission factors. 12 EPA concluded that use of

the Tier 3 method would result in the most accurate es timates amongst the methods presented by the IPCC. 13 By contrast, the Tier 2b is inherently less accurate because it relies on default values for gas consumption, gas utilization, by-product formation, and DREs, and only distinguishes between two br oad process types – etching and cleaning – rather than the roughly 450 pr ocess categories examined u nder Tier 3. The Refined Method represents a middle gro und of sorts, achieving improved accuracy vis-à-vis the Tier 2b method by expanding on the two pr ocess types to include emissions factors

12 See 2006 IPCC Guidelines for National Greenhouse Ga s Inventories at 6.11; see also EPA, Technical Support Document (Updated) for Pr ocess Emissions from Electronics Manufacture (Mar. 22, 2010) (“Electronics Manufacture TSD”) at page 11.

13 Electronics Manufacture TSD (Mar. 22, 2010) at page 12.November 2010 43 specific to nine different refined process categories. 14 While the Refined Method yields

emissions estimations that are approximately twice as accurate as the Tier 2b approach, the Method nonetheless produces es timates that suffer from a high degree of uncertainty. 15 EPA assigned an absolute unce rtainty of + 27,000 MtCo 2 e to the typical semiconductor facility wit h emissions of around 113,000 MtCO 2 e, meaning that a facility’s reported emissions could differ fr om actual emissions by as much as 24
percent. 16 Such a degree of uncertainty is unacc eptably high given the availability of a more accurate reporting method.

While we believe EPA should require Tier 3 reporting for all semiconductor facilities, at minimum, EPA should rely on Tier 3 estimation for ‘large facilities,’ as it did in its initial proposal. As EPA initially concluded, large facilities have the capability to easily collect this data, and as subsequent comments confi rmed, at least one facility already does. 17
Further proof of the fe asibility of Tier 3 estimation is this proposal’s requirement that facilities producing large wafers – greater than 300mm in diameter – employ Tier 3 reporting. We strongly support this requirement and encourage EPA to ensure consistent facility-level data by at least appl ying the Tier 3 requirement to large facilities producing other sizes of wafer as well. At an absolute minimum, any facility that is currently using Tier 3 reporting should be required to report that data to EPA.”

Response 4.2.2.1-c: EPA agrees that the use of the Tier 3 method will result in the most accurate facility-specific emission es timates. However, EPA is mindful of the burden associated with requiring the Tier 3 method to estimate and report emissions from all production processes that use fluori nated GHGs. In the final rule, there are the two methods for estimating emissions for fa cilities that manufacture semiconductors, depending on the annual manufacturing capacity of the facility. One method, the Tier 2d method, which is required for the larges t semiconductor facilities, requires recipespecific emission factors to be used to esti mate emissions for only the etching process type; other emissions would be estimated using EPA-provi ded default factors (a partial Tier 3 approach). The other method, the Tier 2c method, relies only on EPA-provided

default emission factors. In these methods, both of whic h move beyond the Tier 2b method, EPA is balancing the burden placed on industry in implementing a full Tier 3 method against the goal of collecting accurate facility-level information. In addition, EPA has also provided facilitie s with the option to use the Tier 3 method to estimate emissions from all production process that use fluorinated GHGs in lieu of any other method required by the rule. Please s ee response to comment 4.2.1-a and the preamble section D, Electronics Manufacturi ng (subpart I), section 3 (“Summary of Comments and Responses”), for the res ponse to comments on emission estimation

methods for semiconductor facilities.

EPA is also finalizing the requirement for semiconductor manufacturing facilities that fabricate devices on wafers measuring grea ter than 300 mm in diameter, regardless of their manufacturing capacity, to calculat e and report all of t he emissions from

14 75 FR 18656.

15 See footnote 14.

16 See footnote 14.

17 See footnote 14.November 2010 44 processes that use fluorinated GHGs using directly-measured recipe-specific emission factors (i.e., the Tier 3 method). As EPA stated in t he preamble to the April 2010 proposed rule, by including this requirement only for the wafers larger than 300 mm, “we anticipate a reduction in burden because em ission factors (i.e., gas utilization and by-product formation rates) can be dev eloped over a number of years as semiconductor manufacturers begin to tr ansition to 450 mm tools and develop the estimating and reporting infrastructure. T he commissioning process for new tools is an ideal opportunity for emission factor development and/or verification.”

4.2.2.2 Greater than 300 mm Wafer Technologies

Comment Summary 4.2.2.2-a: One commenter (0131) asserted that industry

transitions to new wafer sizes are the best opportunity to introduce new equipment requirements. The commenter asserted that the mo st appropriate introduction point for consistent application of Tier 3 factors is with the introduc tion of production-ready 450

mm tools.

Response 4.2.2.2-a: EPA agrees with the comment er that semiconductor manufacturing facilities that manufacture wa fers greater than 300 mm in size should be required to calculate and report emissions usi ng the Tier 3 method, and in §98.93(a)(4) EPA is finalizing this requirement in the final rule. Please see response to comment 4.2.2.1-c and response to comments in secti on 4.2.2.2 for a more detailed discussion on EPA’s rationale for requiring semiconductor manufacturing facilities that fabricate devices on wafers measuring greater t han 300 mm in diameter (e.g., 450 mm) to calculate and report emissions bas ed on the 2006 IPCC Tier 3 method.

Comment Summary 4.2.2.2-b: One commenter (0110) noted that the adoption of the Tier 3 methodology is a large addition to the overwhelming costs associated with an upgrade to a 450 mm facility. The comment er noted that, depending on the scope of testing, costs could be six or seven figures per facility and add weeks or months to complete. The commenter cit ed a tool manufacturer that would be willing to perform emission factor testing as a customer serv ice provided the customer was willing to pay

extra. The commenter stre ssed that, in the current ec onomic downturn that has affected the semiconductor industry, testi ng would consume financial resources needed for a facility to operate. The commenter not ed that the U.S. Gove rnment Accountability Office (GAO) has cited with approval the measuring, monitoring, and reporting

standards of the EPA Climate Leaders, Chicago Climate Exchange, and the Climate Registry, none of which require Tier 3 estimation methods. 18

Response 4.2.2.2-b: EPA does not agree with the co mmenter that requiring semiconductor manufacturing facilities that manufacture wafers greater than 300 mm to calculate and report emissions using the Ti er 3 method is overly burdensome and costly. For example, one co mmenter (0122) stated that t he total capital budget for a

18 U.S. Government Accountability Office (GAO). High Quality Greenhouse Gas Emissions Data are a Cornerstone of Programs to Address Climate Change. February 24, 2009. http://www.gao.gov/new.items/d09423t.pdf

.November 2010 45 new facility designed to fabricate 300 mm wa fers using 28 nanometer technologies is $4.5 billion. Recognizing that this commenter is providing information that includes new construction costs, the information can st ill be used for general comparison purposes (note, EPA expects that the capital costs of a 450 mm plant to be much more than a 300 mm plant). EPA expects that the costs of Tier 3 meas urements relative to the capital costs of a 450 mm fab are small (see sections 4 & 5 of the Economic Impact Analysis (EIA), available in the docket, EPA-HQ-OAR-2009-0927). 19

The industry transition to 450 mm wafers presents an opportunity, consistent with historical industry practices, reflect ed in International Technology Roadmap for Semiconductors (ITRS) 20 to move the industry forward in terms of emission estimation practices. As operations are being upgraded and constructed, consistent, robust, and accurate practices can be established. Ot her commenters have supported this idea as

well.

EPA acknowledges the GAO has identified exam ples of reporting standards that do not require the use of the Tier 3 method; however , the goals of this final rule are different

from that of the GAO docum ent. The purpose of the final rule is to collect facilityspecific emissions data for use in devel oping future GHG po licies and programs. Collecting accurate data of GHG emissions is important to the future value of the data for informing policy decisions and designing new GHG policies and programs. EPA has concluded that the requirements finalized in this rule accomplish that goal while at the

same time balance burden to t he industry. Please also see the preamble to the Final Rule (74 FR 56265, October 2009) for additi onal discussion on how the GHG Reporting Program relates to EPA and U.S. governmen t climate change efforts and other State and Regional Programs.

Comment Summary 4.2.2.2-c: One commenter (0095) propos ed that R&D facilities

should be allowed to utilize the IPCC Tier 2b methodology instead of the IPCC Tier 3 methodology for estimating emissions from f abricating devices on wafers that are greater than 300 mm. The commenter s uggested this because it would not be financially viable for an R&D facility to do emi ssions testing for a process that is in the concept and feasibility phase.

Response 4.2.2.2-c: EPA is clarifying that if a facility engages in R&D activities, they are not required to report the emissions from that activity. Please see response to

comment 1-b for a more detailed discussi on on the R&D activity exemption.

19 For comparison EPA estimated that the Tier 2d me thod, which requires direct recipe-specific measurements for all etch process at a la rge semiconductor facility will cost $23,407.

20 ITRS (2010) International Technology Roadmap for Semiconductors 2009 . This and earlier editions and updates are available at http:// www.itrs.net/Links/2009ITRS/Home2009.htm.November 2010 46 4.2.3 Alternative Methods for Calculating Emissions from

Semiconductor Facilities

Comment Summary 4.2.3-a : One commenter (0095) stated that electronics manufacturing facilities should be allow ed to utilize the IPCC Tier 2b methodology provided that “...affected tools have point-o f-use abatement units for perfluorinated compounds and DRE published by t he abatement unit vendors for PFCs be equal to or

above those of the IPCC Guidelines.” Other commenters (0108 and 0110) noted that the Tier 2b methodology provides adequate granularity/accuracy with an appropriate level of investment for “relatively smalle r” and large semiconductor facilities. One of these commenters (0110) specifically stated t hat the Tier 2b should be allowed “given the challenges involved in obtaining site-s pecific data for such complex facilities.”

Response 4.2.3-a: EPA does not agree with the comme nters that the IPCC Tier 2b

method should be allowed for semiconductor m anufacturing facilitie s (with or without requiring that each tool has a POU unit atta ched). Although the Tier 2b method may be less costly to implement, EPA does not agree that the Tier 2b method (based on two broad process types) provides adequate granularity/accuracy for any semiconductor manufacturing facility because it does not captur e variability in processes, nor does it

account for emissions fr om wafer cleaning.

Please see the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Comments and Re sponses”), for the response to comments on emission

estimation methods for semiconductor facilities.

For more information on EPA’s rationale for not allowing the use of DREs published by abatement unit vendors or the IPCC defaults, please see response to comments in section 5.2., and also see the preamble sect ion D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”).

Comment Summary 4.2.3-b: One commenter (0122) support ed retaining a single etch category at this time for which a Tier 2b emission factor would be used for estimating and reporting emissions. In a similar regar d, three commenters (0099, 0100, and 0131)

stated that electronics manuf acturing facilities should be allowed to utilize an “Alternative Refined Method” based on 5 proce ss categories – etch, in-situ plasma CVD chamber clean, remote plasma CVD cham ber clean, in-situ thermal CVD chamber clean, and wafer cleans. The commenters st ated that this methodology would improve the accuracy of emissions estimates and al so make gas apportioning less burdensome. The commenters (0099 and 0100) suggested that reporters should use the IPCC Tier

2b and/or EPA NODA emission factors for these five process categories.

Response 4.2.3-b: EPA has decided, in part, to acc ept commenters’ suggestions to retain a single etch process type, with no relating process sub-types. EPA determined

that the available emission fact or data is sufficient to establish default emissions factors for multiple chamber clean process sub-types , but insufficient to support establishing default emission factors for multiple etch pr ocess sub-types. Therefore facilities thatNovember 2010 47 manufacture semiconductors are required to use either default emission factors (the Tier 2c method) or recipe-specific emissi on factors (the Tier 2d method) for the etch process type. In the final rule, for the Tier 2c method, EPA is requiring facilities to use EPA developed default emission fact ors for the etch process type, as opposed to using the IPCC Tier 2b factors as suggested by commenters. The EPA published default

emission factors were develo ped with a more robust set of data than that used to develop the IPCC Tier 2b emission factors. See response to comment 4.2.1-a and the preamble section D, Electronics Manufacturing (subpart I), section 3, for the response

to comments on emission estimation met hods for semiconductor facilities.

Comment Summary 4.2.3-c: Two commenters (0099 and 0131) supported the use of

Tier 3 emission factors for t he Alternative Refined Method if a facility has the Tier 3

factors and if the Tier 3 fa ctors meet the following 2 spec ifications: (1) Factors are “either from tool suppliers and already in t heir physical possession or through a facility’s own measurement methodologies consistent with the IS MI Guidelines”; and (2)

Facilities “conclude that – based on t heir professional judgm ent - factors are representative of their particular process.”

Response 4.2.3-c: EPA agrees with the commenters who suggest that Tier 3 emission factors should be allowed if a facility has them , but only if the facility has Tier 3 factors that represent all production processes that use fluorinated GHGs. EPA is not allowing the use of a hybrid method, or a method using facility-developed default emission factors for process types or sub-types. Th is means that a single facility must choose between using only default emission factors and using recipe-specific emission factors for all process types; hybrid methods us ing both default emissi on factors and recipespecific factors within the same reporting year are not permitted. This restriction will enable EPA to analyze emissions and trends using a consistent set of data. The only exception is where a facility is required to use a method using default emission factors but no defaults are provided in Tabl es I-3, I-4, I-5, I-6, or I-7 for a particular fluorinated GHG and process type or sub-type combinati on. Where defaults are not provided, a facility must either use ut ilization and by-product formation rates of 0 or, in that particular instance, use directly measured recipe-specific emission factors measured using the 2006 ISMI Guidelines, Inte rnational SEMATECH #06124825A-ENG, with limited exceptions. 21

EPA does not agree with comment ers that EPA should allow facilities to estimate emissions using emission factors that were measured with a facility’s methods that

could be consistent with the ISMI Guidelines. Rather, in th e final rule EPA is requiring

that facilities measure their recipe-specific emission factors using the methods specified

in the 2006 ISMI Guidelines or the 2001 ISMI Guidelines provided that measurements were made prior to January 1, 2007. By re quiring the use of the Guidelines, as opposed to allowing facility to use their own methods independently judged as consistent with the Guidelines, EPA can ensure that the met hods for developing

21 EPA is permitting facilities to use emission fa ctors measured using the 2001 ISMI Guidelines, International SEMATECH #01104197A-XFR, provided t he emissions factors were measured prior to January 1, 2007. Documentation for the measurements is required.November 2010 48 emission factors are being used throughout i ndustry are consistent. This will provide EPA with emissions information that can be analyzed and compared across the industry. See response to comment 5.1-a for more details on why EPA is requiring

measurements to be made usin g the ISMI Guidelines.

EPA does not agree facilities should be allo wed to conclude based on professional judgment that emission factors used are representativ e of their own processes, as this method does not provide EPA with any means to verify emissions data being reported. Professional judgment is subjective and dep ends on the values of the person making the judgment. This may create inconsis tencies between facilities when applying the Tier 3 method for fluorinated GHG emissions, particularly given the high variability in the quantities and types of fluorinated GHGs in the vast number of recipes used throughout the industry. Instead, EPA is requiring facilities who obtain Tier 3 emission factors from third parties to ensure, and to provide supporting doc umentation, that the emission factors provided are for recipes that are similar to those used at the facility. 22

Please see the Electronics Manufacture TSD, Appendix D for more details supporting the definition of “similar recipe.”

Comment Summary 4.2.3-d: Two commenters (0099 and 0131) suggested two alternative measurement approaches for fluorinated GHGs and N 2 O; these included the development of an accurate facility-wide em ission factor using statistical parameters and the use of “factory modeling” for new facilities based on representative process steps and gas consumption. Specifically , the commenters sugges ted that a facilitywide emission factor could be established by:

“a) Characterization of the facilities final exhaust using an approved protocol (e.g. 2006 ISMI, 2010 EPA protocol) i) Sampling would include sufficient final exhaust data to understand the variability and develop an average fa ctor and uncertainty range ii) The method could contain a require ment to retest and establish new emission factors if gas us age increased by 20 percent b) Develop an average emission factor with uncertainties comparable to other acceptable methods utilizing the final exhaust data i) Use mass balance to quantify constituents below methods detection limits c) Calculate emissions over time by applying this average emission factor to actual gas consumptions (i.e. emissions = gas consumption * EF)”

The commenters described “factory modeling” as the following: “Factory modeling may be possible for new factories if the appropriate software is integrated into new systems. With the appropriate capability built into new t ools, it may become possible to track tool level gas consumption and develop emission fa ctors for a representative sample of

22 In the final rule, a similar recipe is defined as thos e recipes that have identical chemical compositions and where differences, considered separately, in reac tor pressure, individual gas flows, applied RF power, and flow stabilization time, relative to equipment manufacturers’ best known method or a facility’s process of record, are less than or equal to plus or minus 10 percent.November 2010 49 process steps. Total emissions could then be expressed as a function of chemical use multiplied by the average emission factors.

As measurement technologies are likely to impr ove over time, we believe it is important

that the final rule contain fl exibility that would allow for the use of alternative methods without future rule change.”

The commenters stated that it provided these alternatives because they believe in the importance of flexibility in the final rule to allow alte rnative methods without future

modifications to the rule.

Response 4.2.3-d: EPA agrees that the final rule s hould provide flexible approaches, but only where the methods provide accurate facility-specific emissions data. If an alternative method is developed that is not included in the final rule and EPA

determines that it meets t he goals of the GHG Reporting Pr ogram then in the future, EPA may consider updating the Electronics Manufacturing subpart to allow the use of such an alternative methodology.

EPA is not finalizing the methods the comme nters provided as options because the commenters did not provide sufficient deta ils for EPA to effectively evaluate the accuracy or feasibility of the methods.

4.3 CEMS (Continuous Emissions Monitoring System(s))

Comment Summary 4.3-a: One commenter (0074) states that the use of Fourier transform infrared (FTIR) spectroscopy, as used in continuous emissions monitoring systems(CEMS), is a technology that is we ll established and mature. The commenter noted that technology is curr ently being used in both the electronics industry and the fluorinated GHG manufacturing industry. About using FTI R for CEMS, the commenter

asserted that “the hardware and software ar e readily configurable to a range of applications, and the sampling e quipment is sufficiently re sistant to the corrosive components expected in these proc ess gas streams (e.g., HF, F 2 ) that they operate for

months at a time with littl e or no evidence of damage.” The commenter goes on to present multiple applications and various lo cations in a facility where FTIR CEMS can be used to “cost-effectively m onitor GHG gases as required.”

Response 4.3-a: EPA appreciates the information on FTIR CEMS provided by the

commenter. In the final rule , EPA is not providing for t he use of CEMS for measuring process emissions from electronics manufactu ring facilities. Although the use of CEMS is well established for measuring emissions from single steady flow stacks, such as

stack emissions from stationar y combustion, information availa ble at this time about the technical feasibility, accuracy and costs of estimating emissions from electronics manufacturing using CEMS is limited. CEMS -like emissions monitoring technologies, such as FTIR are being evaluated for this sect or, but they are still in the developmental stages. For these reasons EPA is not including a CEMS method in the rule for electronics manufacturing at this time.November 2010 50 EPA welcomes information on using CEMS to measure GHG emissions from the electronics manufacturing industry . In future years, given more information about the feasibility, implementation methods, and costs of CEMS, and the accuracy of estimating emissions from CEMS, EPA may consider updati ng the rule to allow for the use of this technology for electron ics manufacturing.

Comment Summary 4.3-b: Four commenters (0089, 0110, 0112, and 0131) asserted that CEMS are not appropriate for quant ifying fluorinated GHG emissions from semiconductor manufacturing. According to the commenters, requiring the use of CEMS is unnecessary, potentially not feasib le, and not economically justified. The commenters provided EPA with their insigh t about using CEMS in the electronics manufacturing sector. Thes e commenters stated that CEMS have historically been used to measure single pollutants in steady-s tate processes in stack exhaust streams. This presents an issue for semiconductor manufacturing because these facilities typically use 8-10 different fluorinated GHGs which then flow into an exhaust stream and have 20-30 stacks (for a large facility) . While FTIR has been used for short-term

discrete measurements of the mix of fl uorinated GHGs used at a semiconductor manufacturing facility, FTIR has not been us ed widely for CEMS, and it presents many

inherent difficulties in terms of technology and cos t. One commenter (0 089) stated that “Requiring the use of CEMS would require t he semiconductor manufacturing industry to invest significant resources to devel op and demonstrate some type of continuous monitoring technology that would ultimately st ill yield inaccurate results in place of the currently established conservative approac hes.” Another commenter (0131) also supported the previous statemen t by stating, “even if FTIR could be adapted for CEMS,

the results would be extremel y inaccurate.” Another co mmenter (0110) supported the

continued use of emissions factors and a material balance over CEMS.

Response 4.3-b: It is unclear to EPA how the commenter (0131) arrived at the

conclusion that the results of using FTIR CEMS would be i naccurate, given that CEMS is not widely used throughout industry and EPA is unaware of robust studies comparing

the use of CEMS to other emission es timation methods. EPA would welcome any

further information on which the commenter based the aforementioned assertion, and is interested in further study on the use of CEMS, based on FTIR or other techniques.

At this time EPA agrees that it is not appropriate to require CEMS to estimate

fluorinated GHG emissions in the electronics manufacturing industry. Please see response to comment 4.3-a on the use of CEMS. However EPA is not ruling out the possibility of the use of CEMS in for estimating emissions in the electronics manufacturing source category in the future . Despite the limited information available

about the use of CEMS for electronics m anufacturing (as discussed in comment response 4.3-a) work to establish the us e of CEMS for electronics manufacturing is ongoing, as detailed in one comment er’s (0074) submission.

4.4 N 2 ONovember 2010 51 Comment Summary 4.4-a: One commenter (0131) support ed the inclusion of nitrous oxide (N 2 O) in inventory requirements and views it as an improvement in accuracy of emission reporting when using t he IPCC Tier 2b method.

Response 4.4-a: EPA agrees with the commenter that the inclusion of N 2 O in the facility emissions estimate is an improvement over using the IPCC Tier 2b method to estimate facility emissions, as the IPCC does not provide default N 2 O emission factors,

and hence the IPCC Tier 2b method does not include estimating emissions from the

use of N 2 O.

Comment Summary 4.4-b : One commenter (0112) asse rted that EPA should allow facilities to develop a facility-specific factor for N 2 O utilization through facility testing and

measurement in CVD and ot her processes where N 2 O is used.

Response 4.4-b : EPA agrees with the commenter that facility-specific N 2 O factors

should be allowed. In t he final rule, in §98.93(b), EPA is allowing facilities to develop facility-specific N 2 O utilization factors for CVD and for other N 2 O-using production processes. If a facility elects to use facility-specific N 2 O utilization factors, one must be developed for each CVD and for other N 2 O-using processes. Further, the

measurements must be m ade using the 2006 ISMI Gu idelines, with limited exceptions. 23

4.4.1 Default N 2 O Utilization Factors

Comment Summary 4.4.1-a: One commenter (0112) acc epted EPA’s proposal for a

utilization factor of 0.2 for N 2 O CVD processes, given a lack of detailed data available to justify a higher util ization factor for CVD and other pr ocesses. The commenter stated

that N 2 O is highly reactive and is likely to quickly degrade in the processes. The commenter further stated that it expects ut ilization rates to be higher than 20 percent,

but that there is a la ck of data to justify a higher utilization factor for CVD or other N 2 O using processes.

Response 4.4.1-a: EPA thanks the commenter for t heir support. EPA agrees that at

this time there is a lack of data to justify a default N 2 O factor for CVD higher than 0.2. To this end, in §98.93(b), EPA is finalizing the proposed defaul t utilization factor of 20 percent for N 2 O for CVD. EPA is maintaining the proposed default factor of 0 for other

N 2 O-using manufacturing processes. For more information regarding the N 2 O default factors included in the final rule, pleas e see response to comment 4.4.1-b.

Comment Summary 4.4.1-b: One commenter (0131) noted that it provided data in

their comments to the initial proposed rule to support a 40 percent default factor for CVD processes. The commenter supported the use of 40 perc ent for CVD as it is a

conservative default factor. Two comment ers (0110 and 0131) also proposed the same 40 percent default factor to be applied for other N2O-using processes.

23 See footnote 21.November 2010 52 Response 4.4.1-b: EPA does not agree with the commenter s that a 40 percent default factor should be applied for CVD processes or for other N 2 O-using processes. EPA appreciates the information that one co mmenter submitted previously on N 2 O utilization rates; however, EPA is maintaining the pr oposed utilization factors of 20 percent for CVD and 0 percent for all other N 2 O-using processes as discussed in the following paragraph. 24

While the information the comme nter supplied to EPA about N 2 O utilization was considered in determining the default utiliz ation factors that were proposed and now being finalized, EPA did not accept the comm enter’s suggested 40 percent for several reasons (which were also noted in the pream ble to the proposed ru le). First, the industry survey on which the 40 percent was based was comprised for the most part of

measured utilization factors that were largely from newer 300 mm manufacturing equipment. EPA did not consider the 40 percent as representative because N 2 O utilization of older manufacturing equipm ent, such as 150 mm and 250 mm tools, was not fully represented. In addition, the in formation provided did not fully identify the specific processes from which the average N 2 O utilization factor was calculated. Since the majority of N 2 O is used in CVD processes and given the lack of information

available about the ac tual utilization of N 2 O in other manufacturing processes, EPA only considered the 40 percent value provided by the commenter in finalizing the CVD N 2 O

utilization factor.

Commenters did not provide any additi onal quantitative information on N 2 O utilization factors to support their claims . To this end, EPA was not able to evaluate additional emission factors to develop alternat ive default emission factors for N 2 O. In the future,

based on additional information on N 2 O utilization rates, EPA may consider updating

the N 2 O default emission factors.

Comment Summary 4.4.1-c: One commenter (0095) proposed that EPA should publish a default utilization factor of at l east 50 percent for a CVD process because N 2 O utilization efficiency is relatively high since SiH 4 and N 2 O are relatively reactive with

each other.

Response 4.4.1-c: EPA does not agree with the commenter. While N 2 O and SiH 4 are relatively reactive, if N 2 O is used in any amount that ex ceeds the stochiometric amount

of N 2 O that will react with SiH 4 , that excess amount of N 2 O will be unused and emitted. Information is not currently available to EPA that would s upport utilization factor higher than 20 percent at this time. Further, EPA did not receive additi onal data from the

24 EPA proposed a range of 0 perc ent to 40 percent for the def ault utilization factor for N 2 O for CVD. EPA determined the upper bound of this range through info rmation collected in an industry survey presented in a comment received in response to the initial rule proposal. This industry survey concluded that on average the utilization of N 2 O for all processes at a fab is ~40 percent. EPA selected the lower bound to be conservative. EPA is finalizing the midpoint of this range, 20 percent, as the default CVD N 2 O utilization factor. EPA proposed a defaul t utilization factor of 0 for other N 2 O-using processes due to a lack of information regarding other processes for which N 2 O is used and N 2 O utilization data in those

processes.November 2010 53 commenter to support the higher value. Pl ease see response to comment 4.4.1-b for

more discussion on the default N 2 O factors.

Comment Summary 4.4.1-d: One commenter (0100) proposed that EPA should provide default emissions factor s for all processes using N 2 O.

Response 4.4.1-d: In the final rule EPA is includi ng two default emission factors for

N 2 O- using processes: 20 percent for N 2 O CVD processes and 0 percent for other N 2 Ousing processes. See response to comment 4.4.1-b for additional details on the N 2 O

utilization default em ission factors.

4.5 Heat Transfer Fluids

Comment Summary 4.5-a : One commenter (0108) sugges ted that EPA should not require the use of the deta iled mass balance for HTFs (pro posed Equation I-12) for the “relatively smaller semiconductor facilities.” The commenter alternatively proposed the optional use of an emission fa ctor of 1.0 for simplicity (“i.e., all heat transfer fluid replacement from raw materials stockroom s and heat transfer fluid sent offsite in equipment but not returned would be consider ed emitted”). The commenter suggested that these losses are too low to signi ficantly contribute to a facility’s CO 2 e calculations, especially given that the particular fluids used do not have a published GWP in subpart A. The commenter argued further that to calculate these emissions would be disproportionally resource intensive com pared to any benefit in accuracy. Another commenter (0089) expressed that many of the heat transfer uses occur in closed loop systems that do not require perio dic addition of refrigerant or other onsite service. The commenter asserted that requiring that an in ventory be kept identifying when such units arrive and leave the site is an unnecessary burden that provides no real information about emissions. The commenter argued that the fluorinated heat transfer tracking requirements should focus on consumptive uses of fluorinated liquids such as thermal testing that actually generate emissions.

Response 4.5-a: EPA does not agree with the commenter s. HTFs are widely used in semiconductor manufacturing, regardless of facility size. 25 Further, EPA does not agree that these emissions from the use of H TFs are too low to significantly contribute to total facility emissions in CO 2 e as there is not enough quant itative evidence available to support this conclusion, and the commenter didn’t provide any quantitative detail to support their claim. As stated in 3M’s July 2009 Solid State Technology article

Reduction of PFC emissions from heat transfer fluids

, 26 “A fab’s PFC heat transfer liquid emissions are a significant and growing portion of its total PF C emissions.” In a 3M presentation at the 2010 IH TESH conference the following is also stated, “It is

estimated that a fab’s PFC/ PFPE liquid emissions can be 15-50 percent of its gaseous

25 Please see “Uses and Emissions of Li quid PFC Heat Transfer Fluids from the Electronics Sector (EPA 430-R-06-901), available at http://www.epa.gov/semiconductorpfc/documents/pfc_heat_t ranfer_fluid_emission.pdf

. 26 Please see http://www.electroiq.com/index/display/article-display/365819/articles/solid-statetechnology/semiconductors/material s/2009/07/reduction-of-pfc-emission s-from-heat-transfer-fluids.html.November 2010 54 PFC emissions.” 27 Given EPA’s goals for this rule, EPA believes that it is important to accurately capture the emissions from H TFs as part of overall facility emission estimates. Applying a factor of 1.0 for simplicity as the comm enter suggested does not achieve those goals.

Although in the final rule facilities must r eport emissions of HTFs in absolute mass, not

in CO 2 e, EPA may convert the absolute reported HTF emissions to CO 2 e for comparison purposes across the industry and national GHG emissions. In an EPA report (EPA 430-R-06-901) 28 , EPA estimates that HTFs have GWPs that range from >6,000-9,000 and some are long-liv ed pollutants, persisting in the atmosphere as long as 3200 years. 29 In addition, a commenter (0131) provided input that HTF GWPs range from 55-9,400. EPA does not consi der these GWPs insignificant.

If in the commenter’s assert ion that HTFs are used in closed loop systems, the commenter is also asserting that there are no emissions associated with the use of HTFs, EPA does not agree. There is very lim ited information available about the actual emissions of HTFs. Facilities often top o ff HTFs used in “closed loop systems” (e.g., chillers or heat exchangers) without tracki ng the exact amount that is lost (see EPA 430-R-06-901). 30 Some facilities may collect some portion of the lost material and then ship it off site, although this quantity is typi cally not tracked. Additionally, with the use of HTFs, there are often losses that occur du e to evaporation or leaks, which are also not tracked by facilities. As stated in the 2006 IPCC Guidelines, “3M, a manufacturer of a popular HTF estimates that a vintage 2000 manufacturing plant may lose 1,900 litres/year via evaporation. Manufacturers of testing equipment that use heat transfer fluids report loss rates of approximately 30 litres/year/system for newer designs that reduce evaporative losses and 50 litres/ year/system for older designs.”

While a facility may actually emit a small am ount of HTFs in one reporting year, such as 30 liters/year, given that facilit ies for the most part do not ac tually track HTF losses, the

actual amount of HTFs that facility emits may vary in th e next year due to any changes in evaporation or if any leaks occur. For these reasons, EPA is maintaining its requirement for facilities to use a simple mass balance method, which utilizes inventory quantities, to estimate HTF emissions. The use of this method ensures that emissions due to losses, evaporation, and leaks are a ccounted for in a manner that is less

burdensome than direct measurement and equipment testing. The mass balance method, unlike the methods the comment ers suggested, will provide accurate information about the actual quant ity of HTFs that are being emitted. This method also

27 Liaw, William, Weli Lin and Phillip Tuma. Low GWP Al ternatives to PFC/PFPE Heat Transfer Fluids As a Means to Decrease Facility Gr eenhouse Gas Emissi ons. 3M Electronics Mark ets Material Division.

Presented at the 2010 IHTESH confer ence. HsinChu, Taiwan, 2010. Available in the docket EPA-HQOAR-2009-0927.

28 See footnote 25.

29 Tuma, Phillip and Lew Tousignant. Reducing Emissions of PFC Heat Transfer Fluids. 3M. Presented in the EHS Challenges and Analytical Methodologies session at the SEMI Technical Symposium: Innovations in Semiconductor Manufacturing du ring SEMICON®West, July 16, 2001. Available at: http://multimedia.3m.com/mws/mediawebserver?66 666UuZjcFSLXTtlXfVM8TtEVuQEcuZgVs6EVs6E666

666--.

30 See footnote 25.November 2010 55 allows EPA to compare varying emissions of H TFs consistently across facilities. In the final rule, any facilities reporting under the Mandatory Greenhouse Gas Reporting Rule and engaging in production processes which use fluorinated GHGs as heat transfer fluids to cool process equipment, to contro l temperature during dev ice testing, to clean substrate surfaces and other parts, and for soldering (e.g., vapor phase reflow) are required to use the mass balance method specified in subpart I ((see §98.93(h)) for estimating and reporting HTF emissions.

Comment Summary 4.5-b: One commenter (0089) stat ed that the def inition of

fluorinated HTFs should be more explicit to clarify reporti ng requirements and to focus on materials and uses most likely to generat e emissions. The commenter noted that it is unclear whether the reporting of emissions would be required for fluorinated liquids used in applications other than heat transfer. The comm enter stated that tracking requirements should focus on consumptive uses of fluorinated liquids such as thermal testing that do generate emissions. Anot her commenter (0131) also asserted that HTFs are not only used to transfer heat. These other uses of HTFs are not expected to result in a significant amount of emi ssions, and using the mass balance method may not be warranted. The commenter suggested t hat facilities should not be required to report emissions from the us e of HTFs used for purposes other than transferring heat unless the usage exceeds a de minimis value of 20 kg. The commenter also suggested facilities only be required to report HTFs wit h vapor pressures that exceed 400 Pa and have an assigned IPCC AR4 GWP value. (See al so the de minimis reporting threshold section 2.3)

Response 4.5-b: In regards to the commenter who suggested that EPA should focus on the uses of HTFs most likely to gener ate emissions, EPA does not agree with this suggestion. All uses of HTFs may generate em issions. To single out certain uses of HTFs to be reported will give EPA an incomple te picture of actual HTF emissions. EPA also disagrees that is unclear whether HTFs used in all appl ications must be reported. As stated in the rule for subpart I, HTFs are defined as fluorinated GHGs used for temperature control, device testing, and soldering in certain types of electronic manufacturing production processes. HTFs used in the electronics sector include perfluoropolyethers, perfluoroalkanes, perfl uoroethers, tertiary perfluoroamines, and perfluorocyclic ethers. HTFs commonly us ed in electronics manufacturing include

those sold under the trade names "Galden® " and "FluorinertTM." Electronics manufacturers may also use these same fluorinated chemicals to clean substrate surfaces and other parts. By defining HTFs in this manner, EPA intends to capture HTFs that are used for transferring heat and for other uses such as cleaning substrates. EPA appreciates the input from the comment er who suggested a de minimis value of 20 kg for HTFs with vapor pressures that exceed 400 Pa and have an assigned IPCC AR4 GWP value. However, EPA does not agree with the suggestion as discussed in responses to comments in Section 2.2.

Comment Summary 4.5-c: One commenter (0131) sugges ted a mass balance method that is keyed to purchase and offsite shipment for HTFs.November 2010 56 Response 4.5-c : EPA appreciates the commenter’s suggestion, however EPA did not modify the mass balance that facilities are required to use to determine HTF emissions

in the final rule. EPA does not believe that the method the commenter suggested will accurately capture HTF emissions because it is not a complete mass balance method as required in the final rule. The commenter’s suggested method does not take into account the complete picture of the use of HTFs in a facility, as it appears the commenter is neglecting to account for the inventory of HTFs stored onsite at the beginning and end of the reporting year. All purchases of HTFs may not be used in a reporting year, and in this instance a mass balance method that accounts only for purchases and offsite shipments, as opposed to accounting for the inventory of HTFs stored on-site as well, may result in an overestimation of HTF emissions.

Requiring beginning and end of year invent ories is also a QA/QC measure for EPA and a facility. If end of year inventories do not equal beginning of the subsequent year inventories it is a signal t hat inventorying or emission estimations methods may not have been carried out properly.

Please see response to comment 4.5-a for a dditional information on EPA’s rationale for finalizing methods for estimati ng emissions from HTFs.

Comment Summary 4.5-d: One commenter (0131) sugges ted alternative variable

definitions for the HTF mass balan ce equation, as it found some of the definitions to be confusing. The commenter also identified an error in the units assigned to variables in the equation.

Response 4.5-d: EPA appreciates the commenter’s suggestions. EPA has accepted two of the commenter’s pr oposed definitions of vari ables, for the variable I io and for I it

. These variable definitions have been revised as follows:

I io = Inventory of fluorinated heat transfer fluid i (in containers, not equipment) in containers other than equipment at the beginning of the reporting year (in stock or storage)

.

I it = Inventory of fluorinated heat transfer fluid i (in containers, not equipment) in containers other than equipment at the end of curr ent reporting year (in stock or storage)

.

EPA has not revised other variable definitions in the HTF mass balance equation because EPA does not agree that the commenter ’s suggestions improv e the clarity of

the definitions. In t he final rule, EPA corrected the unit assignment error for the input of the mass balance equation.November 2010 57 

### 5. Monitoring and QA/QC Requirements

5.1 Use of the 2006 ISMI Guidelines

Comment Summary 5.1-a: One commenter (0089) proposed that the requirement to use the 2006 ISMI guidelines for developing site-specific emission factors apply only

from the effective date of t he final rule onward. The co mmenter proposed that emission factors and DRE values developed prior to the final rule’s effective date be “grandfathered” in by not requiring adher ence to the 2006 ISMI Guidelines. The commenter noted that many si te-specific emission factors were developed from testing prior to 2006 and thus would not qualify. T he commenter asserted that this would discourage the use of the Ti er 3 method under this regu lation. Furthermore, the

commenter asserted that test s performed more recently ma y not meet the requirement since prior documentation may be lacking to veri fy the use of the 2006 ISMI Guidelines, as there was no regulatory requi rement in place previously that would have required

facilities to maintain this documentation. The commenter asserted that retesting process tools in accordance with 2006 ISMI Guidelines would likely take years.

Response 5.1-a: This rule’s reporting requirements ar e prospective only. For facilities to use historical emissions measurements, EPA needs to verify that appropriate QA/QC procedures were followed for any measur ements made and factored into emission estimation methods, regardless of when the measurements occurred, to ensure the quality of the data being used to estimate emissions. In general, EPA designed these requirements with the expectat ion that the measurements would be made in future. However, to provide more flexibility for facilities that have already made Tier 3 measurements prior to the publication of t he rule, EPA is allowing facilities to use measurements made in the past if sufficient supporting docum entation is available.

EPA is understanding of the bur den that requiring only the use of the 2006 ISMI Guidelines may impose on facilities that have already developed Tier 3 emission factors prior to the publication of t he final rule. Therefore, for measurements made to develop recipe-specific factors prior to January 1, 2007, EPA is permitting facilities to use factors developed in accordanc e with the 2001 ISMI Guidelines in the final rule. This flexibility will allow facilities to use meas urements made prior to the publication of the

2006 ISMI Guidelines.

EPA is not, however, allowing facilities to report measurements that were not made using either the 2006 or 2001 IS MI Guidelines. Requiring the use of the 2006 or 2001 ISMI Guidelines, which were developed by and within the industry, is the means for

EPA to ensure that measured emission factors are robust, consistent, repeatable, and precise. By requiring that emission fact ors be measured using the 2001 or 2006 ISMI Guidelines, EPA is relying on the only est ablished industry practices for quantitatively characterizing emissions under conditions of actual wafer processing. 31 DRE values developed prior to publication of the EPA’s DRE Protocol can be utilized as long as

31 According to the authors listed to the antecedent guidelines, the Guidelines were not only developed among industry experts. ISMI sought and secured the ex pertise of NIST, a federal technology agency, in developing its guidelines for characterizing emissions.November 2010 58 documentation demonstrates compliance with the principles and requirements of the

Protocol.

For additional responses to comment on the required use of EPA’s DRE Protocol see

section 5.2.4.1. For more information on the required documentat ion for historical emission measurements made using the 2001 or 2006 ISMI Guidelines please see response to comment 7-b.

5.2 Controlled Emissions from Abatement Systems

Comment Summary 5.2-a: One commenter (0112) assert ed that facilities should be able to receive credit for the performance of the PFC gas destruction systems in which they have invested.

Response 5.2-a: EPA’s final rule does not prohibit a facility from accounting for a

fluorinated GHG and N 2 O abatement systems’ properly measured performance. EPA is requiring facilities to adhere to methods that will help ensure controlled emissions are accurately reflected in facilities’ total em ission estimates. Based on the information available to EPA at this time, EPA is prov iding facilities with two options, with various levels of associated burden, to account fo r the use of abatement systems. In using

either method to account for the use of abatement systems (i.e., either EPA’s default DRE or properly measured DREs), facilitie s must ensure that abatement systems are properly installed, operated, and maintained, and that facili ties account for abatement system uptime. For more details on the importance of these components and discussion on why they are required to receiv e credit for the use of abatement systems, see the preamble to the April 2010 proposed rule (75 FR 18667, April 2010). Please

also see sections 5.2.1 and 5.2.2 for informa tion on proper installation, operation, and maintenance of abatement systems and a ccounting for abatement system uptime, respectively.

One of the methods provided in the rule to account for the use of fluorinated GHG and

N 2 O abatement systems, the use of EPA’s default DRE, strike s an appropriate balance between being conservative and being repr esentative where equipment is properly operated and maintained. The second met hod, using properly measured DREs, requires gradual testing of a ll abatement systems, and retest ing individual abatement systems over time. While this may be mo re burdensome than using a default DRE, it offers facilities an option to more accurate ly reflect the use of fluorinated GHG and N 2 O abatement systems. For more discussion on the use of proper ly measured DREs, please see the preamble to t he April 2010 proposed rule ( 75 FR 18668, April 2010), as

well as section 5.2.4.

Comment Summary 5.2-b: One commenter (0112) proposed that facilities be allowed

to calculate fluorinated GHG emissions bas ed upon gas used multiplied by 1 minus the DRE for destruction systems without having to adjust for utilization if the facility so

chooses. The commenter asserted that this will result in conservative reporting ofNovember 2010 59 emissions, would simplify the emissions ca lculations, and would avoid unnecessary process analysis work.

Response 5.2-b: EPA does not agree with the comment er’s suggestion that emissions can be estimated using only the amount of fluorinated GHGs consumed and a DRE, without taking into account gas utilization in the process tool. Although EPA agrees that the method proposed by the commenter will result in an overestimation of emissions, it would be inconsistent with a goal of this rule in having facilities report accurate emissions. In some cases, the amount of gas utilized in a process may be as much as 90 percent or higher’ 32 not accounting for this in estimating emissions will lead to known and preventable inaccuracies in da ta reported to EPA. EPA intends to use the accurate facility specific information gather ed by this program to inform future policy design and regulatory decisions . EPA has concluded that the method suggested by the commenter is not sufficient for this purpose.

5.2.1 Proper Installation, Op eration, and Maintenance

Comment Summary 5.2.1-a: One commenter (0128) st rongly supported EPA’s emphasis on ensuring proper installation, operation, and maintenance of abatement systems. The commenter noted that the variabili ty in DREs is partially attributable to installation and maintenance practices. The commenter asse rted that independent inspection and maintenance is essential to ensure that default DREs bear some relationship to real emissions.

Response 5.2.1-a: EPA appreciates the commenter ’s support for the required certification of properly installed, operated, and maintain ed abatement systems. However, EPA does not agree with the comm enter’s assertion that independent inspection and maintenance is essential for ensuring that default DREs reflect actual emissions. While independent inspections may be effective, requiring independent inspection and maintenance would be burdensome fo r facilities. Ther efore, to reduce burden, EPA is permitting facilities to self -certify proper installation, operation, and maintenance by documenting that the abatem ent systems are installed, operated, and

maintained in accordance with abatement system manufacturer s’ specifications.

Comment Summary 5.2.1-b: Two commenters (0110 and 0123) asserted that on-site, independent inspection of abatement system installation, operation, and maintenance is unnecessary and burdensome, particularly on an annual basis. The commenters suggested that facilities be allowed to self -certify proper installation, operation, and maintenance of abatement systems as self-c ertification is allowed for compliance and enforcement for similar permi t conditions under the CAA.

Two other commenters (0099 and 0131) stated t hat third-party quality assurance and inspection of abatement systems is unneces sary. The commenters asserted that certification by a responsible company offi cial is consistent with other programs and

32 As demonstrated in Table 5 of the report Dr aft Emission Factors for Refined Semiconductor Manufacturing Process Categories (EPA-HQ-OAR-2009-0927-0073).November 2010 60 appropriate for fluorinated GH G reporting. The commenter s expressed concern that restricting the facility to only the abat ement equipment manufacturers’ maintenance specifications would not allow for future improvement in operational and maintenance procedures, and that the require ment, which restricts facilities to staying within abatement systems manufacturer inst allation, operation and maintenance specifications, may not allow compet ition for maintenance contracts.

Response 5.2.1-b: While independent inspections may be effective, EPA has determined that requiring independent inspection and maintenance would be more

burdensome for facilities. EPA is therefore permitting facilit ies to self-certify proper installation, operation, and maintenance by providing documentat ion that abatement systems are installed, operated, and mainta ined in accordance wit h abatement system manufacturers’ specifications. EPA does not find it plausible that requiring facilities to follow manufacturers’ specifications w ould preclude further improvements in O&M procedures or practices. Facilities may adopt additional measures as long as they do not conflict with the rule requirements. Additionally, no part of the requirement specifically limits to whom a facility ma y award maintenance contracts. Please see response to comment 5.2.1-a.

5.2.2 Accounting for Abatement System Uptime

Comment Summary 5.2.2-a: One commenter (0131) confi rmed that facilities may be able to monitor abatement system operations , but the commenter also cited ISMI survey findings that additional labor and cost will be required to install and maintain monitoring systems to track uptime. The commenter pro posed: “That EPA allow for a facility specific monitoring systems and to calc ulate uptime as the per cent of the total abatement operation and in cluded in the fraction of input gas in Eqs. I-7 and I-8 and multiplied by the DRE in the equation.”

Response 5.2.2-a: EPA maintains that applying a DRE value that is not discounted for abatement system uptime would result in an underestimation of total facility emissions as abatement system s are not fully operational for 100 percent of the reporting year. For example, the time during which a system is by-passed, undergoing maintenance, or not operating with O 2 -flow (in the case of a CF 4 combustion system)

should not be taken into account 33 when estimating and reporti ng controlled emissions

as this would result in a mis-estimation of controlled emissions. EPA is providing two new equations in the final rule (Equations I- 14 and I-15) to which facilities must adhere when calculating uptime of an abatement syst em, and when accounting for uptime in the DRE values applied to estimate emissions . EPA is not specifying the methods that a facility must use to monito r the parameters required to ca lculate uptime of abatement systems (the total time each abatement system is in operational mode and fluorinated

33 An exception to this is time during which ex haust flows are passed through a redundant abatement system that is in the same abatem ent system class (discussed below ) as the primary abatement system. Such time may be included in the uptime of the primary system. A redundant abatement system is defined as a system that is specif ically designed, installed and opera ted for the purpose of destroying

fluorinated GHGs and N 2 O gases. A redundant abatement system is used as a backup to the main

fluorinated GHGs and N 2 O abatement system during those time s when the main system is not functioning or operating in accordance wi th design and operating specifications.November 2010 61 GHGs or N 2 O are flowing through the connected process tools and the total time

fluorinated GHGs or N 2 O are flowing through proc ess tools connected to each abatement system). See response to comment s in section 5.2.2 and the preamble section D, Electronics Manufacturing (subpa rt I), section 3, for the response to comments on uptime.

Comment Summary 5.2.2-b: Two commenters (0089 and 0112) indicated that it is reasonable for EPA to require consideration of abatement unit uptim e, but that the specific procedures outlined in the rule may not reflect actual practices of facilities. The

commenters stated that their POU abatement devices are inte rlocked with fab tools, so

that the tools will shut down at abatement device failure or at the end of the wafer run. In either case, the commenter s asserted that the tool c annot be further operated until the abatement device is operational. One commenter (0112) proposed, “An option for tracking abatement device uptime for systems with a tool interlock by reporting the

number of times an abatement unit failure o ccurred. Where the tool shuts down when the abatement device fails, no adjustment to the emissions calculations would be

needed. For those situations where the tool continues to run, a process could be worked out estimate the additional gas emi ssions per chamber process for tool type and the calculated emissions increased by t hat quantity of additional emissions times

the number of times the tool fa iled. If possible, the rule should allow companies to do a significance test and establish a minimal num ber of failures below which the additional emissions are not significant (say a half a pe rcent of the total emi ssions for a specific gas).” One commenter (0089) as serted that a viable method for determining uptime for

interlocked abatement tools should involve documenting that t ools are in fact interlocked and documenting instances wher e failure occurred during processing.

Two other commenters (0110 and 0123) stated that their POU abatement systems are typically configured that if the abatement system is do wn or operating abnormally, the system will either shut down gas to the process tool or di vert flow to a redundant abatement system. The comment ers asserted that allowance of this method ensures proper abatement and accurate emissions estimates without additional costs associated with tracking and recording abat ement system uptime parameters. The commenters suggested that significant additi onal costs would be incurred to otherwise modify or upgrade operational co ntrols and data acquisition systems.

Response 5.2.2-b: EPA is not modifying uptime r equirements as suggested because EPA expects that facilities with interlocked abatement systems should be able to easily monitor and account for uptime of abatement systems using the methods provided in this rule. EPA is also not modifying the uptime requirements to accommodate one commenter’s suggestion of developing and es tablishing a significant test for determining the number of systems failures for which emissions would be insignificant. Such a test may be practical, however EPA does not have and the commenter did not offer any data regarding the nature or support for such a test.

EPA is not permitting facilities to use the me thods suggested by the commenters as this would allow the use of multiple methods to monitor and account for uptime. WhereNovember 2010 62 feasible, EPA would like to ensure that fa cilities are using consistent methods in estimating emissions because this will create a consistent basis on which to compare industry emissions and will also reduce EPA’ s administrative burden. EPA is requiring detailed monitoring and reporting of uptime because this information will allow EPA to carry out emissions verification to ensur e the consistency and accuracy of data collected under this rule. See response to comment 5.2.2-a on requiring facilities to account for uptime and the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Resp onses”), for the response to comments on uptime and interlocked abatement systems.

5.2.2.1 Semi E-10 Standard

Comment Summary 5.2.2.1-a: One commenter (0093) ar gued that: “the abatement system uptime calculation described in t he proposed rule does not comply with SEMI

E10-0304 E , which does not include the concept of co-dependent uptimes of different equipment (e.g., abatement system s and associated manufacturing tool(s)) in any of its

metrics. Based on the classification of ti me periods (e.g., productive time) listed and assuming that these time periods have the sa me definitions as in SEMI E10-0304E, the

commenter asserted that the calculation is ve ry similar to, but is not the same as, the operational uptime formula defined in SEMI E10-0304E paragraph 6.3.3.” The

commenter asked that references to SEM I E10-0304E in the rule should be removed and that the appropriate calc ulation and its individual terms be completely defined

within the EPA document unless the EPA dete rmines that one of the SEMI E10-0304E formulas may be used. The commenter propos ed that EPA edit the original language of Proposed subpart I, Section 98 .94(f)(2) to read as follows:

“(2) You shall take into account and r eport the uptime of abatement systems when using destruction or removal efficiencies to reflect emission reductions. Abatement system uptime is expressed the total time the abatement system is operating when greenhouse gas(es) is flowing in process tool divided by the total time during which the process tool is flowing greenhouse gas(es). This calculation must be done for each greenhouse gas and combination of process t ool(s) and abatement system(s), and can be summed into one value for each greenhouse gas for each facility.

The uptime calculation must be perform ed for each greenhouse gas, and it shall be

ensured that abatement devices are operating in a mode ap propriate to abate that specific greenhouse gas. For example, the abatement devic e may be capable of destroying SF 6 to 90 percent, but only 60 percent for CF 4 . If the abatement device has been put into bypass during maintenance, this does not count as upt ime, regardless of any activity on the process tool.”

Response 5.2.2.1-a: EPA modified the procedures for ca lculating and accounting for uptime by removing reference to SEMI E-10-0304 E because EPA agrees with the

commenter that SEMI E-10-0304 E does not fit appropriately in the rule. EPA has taken the concept presented by the commenter in the suggested regulatory text and has modified it accordingly to fit within the regulator y text of the final rule . In the final rule, EPA is requiring facilities to calculate an aba tement system’s uptime by taking the ratioNovember 2010 63 of (1) The total time during which the abat ement system is in an operational mode when

fluorinated GHGs or N 2 O are flowing through production process tool(s) connected to that abatement system, to (2) the total time during which fluorinated GHG or N 2 O in

which fluorinated GHGs or N 2 O are flowing through production process tool(s) connected to that abatement system (s ee §98.98). Further, EPA has defined operational mode as the time in which an a batement system is being operated within the range of parameters as specified in t he operations manual provided by the system manufacturer (see §98.98). Please also s ee the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summa ry of Comments and Responses”), for response to comments on uptime.

5.2.3 EPA Default DRE Value

Comment Summary 5.2.3-a: One commenter (0128) stated that it recognizes that abatement systems often have a high DRE and are an important factor in accurate accounting of overall emissions. However, the commenter raised concerns with EPA’s proposal and stated that the abatement estimation flexibilit ies in the proposal do not accurately capture abatement systems’ DRE s. The commenter was also concerned that EPA’s default DRE is based upon a sma ll sample size of diverse abatement technologies, and that existi ng IPCC and industry DRE fact ors also are inadequate. Therefore, the commenter enc ouraged EPA to permit reporters to rely only on properly

measured DREs to better account for vari ability in installation, operation, and maintenance practices.

Response 5.2.3-a: EPA maintains that the use of properly measured DREs will result in more accurate emission estimates; however, EPA finalized provisions to permit

facilities to use a default DRE as a means to reduce burden on facilities that are properly equipped and would like to account for controlled emissions due to the use of abatement systems. EPA developed the default DRE with the best and only information available to the Agency at this time. 34 The data available to EPA are limited today and additional data were not made av ailable by way of the public review and comment process. EPA agrees with the commenter that IPCC and industry default DRE factors are inadequate for pu rposes of this rule (see response to comment 5.2.3-c

and the Electronics Manufacture TSD for a di scussion on why EPA is not permitting the use of IPCC and manufacturer provided default DREs).

Comment Summary 5.2.3-b: Six commenters (0099, 0110, 0112, 0122, 0123, and 0131) asserted that the propos ed default factor of 60 per cent for the DRE of all abatement systems is overly conservative (l ow) and would over-state emissions from facilities with abatement systems. Tw o commenters (0099 and 0131) appreciated EPA’s approach to establish and provide def ault DRE values for abatement systems. However, one commenter (0131) noted that the proposed 60 percent default factor is

based on the destruction of CF 4 , and should not apply to other fluorinated GHGs where

34 The 60 percent default DRE value was calculated us ing data from measurement s assured to properly account for the effects of dilution. In addition, t he tested systems were proper ly installed, operated, and

maintained.November 2010 64 emissions would be significantly overstated. One commenter (0122) specifically argued

that because of the low value of the default DRE, the practical value of investments in abatement technology will be r educed, and it may be a disincentive for voluntary adoption of abatement technologies. Other commenters (0099 and 0131) stated that the 60 percent default value penalizes semiconductor manufacturers who have voluntarily employed POU devices under the EPA and indus try voluntary MOU and other GHG-reduction programs.

Response 5.2.3-b: EPA’s default DRE was developed based on the only publicly data which properly accounted for t he effects of dilution available to EPA at this time. While

commenters asserted that EPA’s default DRE value is too low, EPA did not receive any further information or data in the public co mments that would lead EPA to revise this value. In regards to the commenters that stated the 60 percent default value penalizes

semiconductor manufacturers who have vo luntarily employed PO U devices under the EPA and industry voluntary MOU and other GHG-reduction programs, EPA does not agree. Although EPA is unsure exactly to wh ich “other GHG-redu ction programs” the commenter is referring, in contrast to ot her regulatory programs th at generally focus on whether a facility's emissions are below a specified limit, this rule focuses on establishing each facility’s annual GHG emissi ons in tons per year. For this reason, EPA is finalizing certain requirements in this rule to ensure that EPA receives accurate facility-level emissions data. Please al so see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summa ry of Comments and Responses”), for response to comments on the default DRE value.

In light of the widely reported variabi lity in fluorinated GHG abatement system performance, 35 and in order to provide a default DRE option in the final rule, EPA had to rely on data obtained through the EPA DR E measurement program (mainly CF 4 DREs).

Please see the Electronics Manufacture TSD fo r more information on the data used for and the development of the EPA default DRE. Please also see response to comment 5.2.3-c on why EPA is not relying on manufacturer or the IPCC default DRE.

Because some facilities have already adopted abatement technologies as a means to reduce fluorinated GHG emissions, EPA doe s not agree that t he default DRE will reduce the practical value of investments in abatement technologies, be a disincentive for the use of abatement technologies, or penalize those who have voluntarily adopted abatement technologies at their facilities. The default DRE is provided in this rule to offer facilities an option, alternative to properly measuring abatement system DREs which is also provided in the final rule, to account for the performance of installed abatement systems.

Comment Summary 5.2.3-c: Two commenters (0099 and 0112) proposed that a facility be allowed to use a manufacturer’s ce rtified destruction factor discounted by 10

35 Beu, L. (2005). “Reduction of Perfluorocar bon (PFC) Emissions: 2005 State-of-the-Technology Report”, TT#0510469A-ENG, International SEMATECH Manufacturing Initiative (ISMI), December 2005.

Available at: http://www.epa.gov/highgwp/semiconductor-pfc/documents/final_tt_report.pdfNovember 2010 65 percent to account for potentia l field conditions and result in the application of DREs

that are more accurate. O ne commenter (0112) stated that this would be consistent with EPA’s proposal in 2009 where EPA allow ed the use of manufacturer’s DRE data generated using the EPA abatement systems testing protocol.

Another commenter (0131) pr oposed the following in relation to the use of default

DREs: “Provide additional default factors for C 2 F 6 and the other fluorinated GHGs that

are easier to abate. Allow the use of manuf acturer’s certified DREs discounted by 10 percent to account for differences between field and lab certification conditions.

Discounted manufacturer’s DREs would acco unt for both the installed equipment’s capability and the slight reductions in DREs resulting from use under field conditions. Note, EPA’s 2009 proposal allowed the use of manufacturer’s DRE data generated using the EPA abatement systems testi ng protocol. Systems processing CF 4 emissions would continue to use the EPA 60 percent def ault DRE. Allow facilities to calculate emissions using the average DRE for a gas or gas type determined by testing a representative sample of abatement units. Th ese methods will result in the application

of more accurate DREs.” Another comment er (0099) expressed the same sentiments regarding the use of other default DREs for fl uorinated GHGs that are easier to abate

and to the use of manufacturer DREs.

Two commenters (0110 and 0123) suggested it is contradictory that EPA is not permitting the use of IPCC default factors or supplier provided DRE values and EPA is also requiring abatement systems to be in stalled, operated, and maintained in

accordance with manufacturers’ recommendati ons. Facilities should be permitted to

use IPCC and manufacturer DRE values (which commenter 0110 asserted are based on measurement data). Anot her commenter (0122) added that there is substantial experience in the industry t hat point of use (POU) abatement devices achieve DREs from 95-99 percent, notwithst anding some examples of poor ly installed or operated equipment. The commenter stat ed that it is therefore reasonable to rely on the guarantees of abatement system manufacturers regarding the performance of their equipment, along with the appropr iate diligence to ensure proper installation and monitoring of field operations.

Response 5.2.3-c: In the original April 2009 propos al, EPA did propose to permit a third party (e.g., Underwriters Labs) to te st abatement equipment on behalf of the

manufacturer of the abatem ent equipment; testing would be done on representative samples of the abatement equipment in or der to verify the DRE of abatement equipment. Under this approach, electronics manufacturing facilities would have been required to buy equipment that had been certif ied under this third-party testing. EPA does not agree that the commenter’s s uggested method to use manufacturer guaranteed DREs discounted by 10 percent is consistent with t he approach proposed in the April 2009 rule for two reasons. First, EPA’s proposal did not mention discounting manufacturer supplied DREs, an d the commenter did not provide EPA with any independently determined data supporting the selection of the discount value of 10 percent. The 10 percent discount appears arbi trary and was not accompanied by any empirical data. Second, the commenter di d not specify if manuf acturer supplied DRE must be developed consistently and properly to account for the effects of dilution (e.g.,November 2010 66 using EPA’s DRE Protocol). A t the time of the original proposed rule (April 2009) EPA’s DRE Protocol had not yet been completed, but EPA proposed that all abatement system testing be performed with an industry standar d or protocol, or using a consistent approach, such as the in-development EPA DRE Protocol, to ensure dilution would be properly accounted for. However, EPA is not aware of any abatement system

manufacturers who have used the EPA DRE Prot ocol to develop manufacturer claimed

DREs.

EPA does not support the use of manufacturer supplie d DREs even with proper installation and monitoring of abatement systems. Manufa cturer supplied DREs may

result in emissions estimates that are not representative of actual facility operations because the DRE itself may have been incorrectly measured due to a failure to account for the effects of dilution (e.g., CF 4 can be off by as much as a factor of 20 to 50 and

C 2 F 6 can be off by a factor of up to 10 [Bur ton, 2007].) This under standing is supported by industry assessments as presented in Beu, 2005. Please see the April 2010 preamble (75 FR 18668, Apr il 2010) and the Electronics Manufacture TSD for the reasons why abatement system manufacturer supplied DREs are not permitted in the

final rule.

EPA also does not support the use of the IP CC default DRE in this rule because the IPCC default DRE was chosen by consensus prior to EPA developing its DRE testing program. The IPCC default DR E was based on anecdotal information rather than the

direct in-fab measurements EPA used to dev elop its default value for DRE. The

uncertainties associated with the IPCC defau lt DRE helped spur EPA to embark on its DRE measurement program wit h its industry Partners.

EPA acknowledges that the 2009 proposal would have allowed for abatement system manufacturers to develop DREs using t he EPA DRE Protocol. However, EPA has reassessed this requirement and is not a llowing the use of any abatement equipment manufacturer supplied DREs because EPA has concluded that DREs developed in outof-fab settings may not be r epresentative of DREs achieved during full production, infab conditions. Abatement device manufactu rer-specified installation, operation, and maintenance practices are based upon the testing and development of abatement systems in controlled settings that are not ex perimentally establish ed as representative of actual fab environments. When using thes e systems in actual fab settings, ensuring the proper installation, operation, and ma intenance of abatement systems may not guarantee that the abatement system will perform as abatement manufacturers intended, or that the manufac turer supplied DRE will be achieved. EPA’s in-fab DRE testing revealed that abatement system perform ance was well below promises provided by abatement systems manufacturers. Addi tionally, EPA has no information that supports claims that continual maintenanc e in accordance with abatement system manufacturer supplied schedules will ensur e that abatement systems will meet their designed expectations indefinitely. Theref ore, EPA is not permitting the use of manufacturer supplied DREs in any instance, including instances where facilities adhere to manufacturer specifications and instances where the manufacturer developed their guaranteed DREs using the EPA DRE Protocol. Please see response

to comments 5.2.3-b and c for more details on EPA’s default DRE. Please also see theNovember 2010 67 preamble section D, Electronics Manufacturing (subpart I), section 3, for the response

to comments on the default DRE and properly measured DREs.

5.2.3.1 System Certification

Comment Summary 5.2.3.1-a: Two commenters (0089 and 0108) requested further explanation of the proposed certification of abatement systems. One commenter (0108) requested clarification on who certifies the two a pparent certification types (proper installation, operation, and maint enance, and abatement system design), how often the certification must occur, in what form and containing what specific information, and whether EPA envisions third-party certif ication. The commenter was concerned that a foreign manufacturer of abatement sy stems may be reluctant to participate in a design certification scheme by a foreign regulatory agency. One commenter (0089)

was uncertain whether existi ng abatement equipment would r equire certification. The commenter suggested that certain technologie s (e.g., thermal destr uction) that have been widely used for PFCs could be considered “certified” if they meet certain key operating parameters (e.g., combustion temperature).

Response 5.2.3.1-a: In the final rule, EPA is requiring any facility that wants to account for the use of abatement syst ems to certify and document that their abatement systems (either those previously insta lled or newly installed) are or have been properly installed, operated, and maintained. A facility must sh ow this by self-certifying the proper installation, operation, and maintenance, and providing EPA with documentation that proves that abatement systems are/were installed, operated, and maintained in

accordance with the manufacturers' specifications. Alternately, if a facility elects to use the EPA default DRE value, a facility must certify that the abat ement system, either existing or new, for which the default DRE is being applied, is designed specifically to

abate fluorinated GHG and N 2 O. EPA clarified in the final rule that a facility must support its certification t hat the abatement sy stem is designed specifically for

fluorinated GHG and N 2 O abatement by documenting and reporting the abatement system supplier’s specifications for the system (see §98.96(q))

. A facility may provide

this certification without t he involvement of third parties . Therefore, because adhering to this certification only requires a facility to obtain the design specifications of abatement systems, which should be part of BAU docum entation that is provided when a facility purchases a system, EPA does not foresee t he need to involve foreign manufacturers in facility self-certification. EPA does not agree with one commenter’s suggestion that certain technologies (e.g., thermal destruc tion) that have been widely used for PFCs could be considered “certified” if they meet certain key operating parameters, as the method suggested by the commenter would co mplicate the verification of the proper installation, maintenance, or design of syst ems. Further, while manufacturers of thermal destruction systems cite the import ance of temperature in determining DRE performance, peer review comments on t he EPA DRE Protocol (see response to comments on the DRE Protocol, available in docket EPA-HQ-OAR-2009-0927) noted the difficulties in knowing and measuring what this temperat ure is for installed systems. Because of these concerns, EPA removed temperature as a parameter to decide whether a system was capable of abating CF 4 , for example. See the section 5.2.1 andNovember 2010 68 the Electronics Manufacture TSD for more di scussion on proper installation, operation,

and maintenance.

5.2.4 Proper Measurement of Abatement DRE

Comment Summary 5.2.4-a: One commenter (0128) en couraged EPA to finalize a rule that relies exclusively on direct m easurement for DRE factors. The commenter

asserted that direct measurement of abatem ent efficiency maximizes accuracy and can

better account for variabi lity across facilities in installa tion, maintenance, and operation.

Response 5.2.4-a: Although direct, proper measurement of DREs will more accurately reflect the use of abatement systems, as well as account for variability among abatement systems, EPA is mindful of the bur den direct measurement may impose on a facility. To reduce burden, EPA is maintaini ng the option in the final rule for facilities to report controlled emissions from the use of fluorinated GHG and N 2 O abatement systems, using a default DRE provided that t he systems are certified as being designed

to abate fluorinated GHGs and N 2 O. See section 5.2.3 for mo re details on the default DRE provided in the rule. Additionally, as a way for EPA to ensure that variability due to installation, operation, and maintenance practices is reduced, facilities that use EPA’s default DRE are also required to veri fy the proper installation, operation and

maintenance of the abatement systems for which the defaul t DRE is being applied. The same verification is also requir ed when using proper ly measured DREs.

Comment Summary 5.2.4-b: One commenter (0089) expr essed concern that DREs obtained from abatement system testing performed prior to the publication of the EPA DRE Protocol are not permitted to be used. The commenter asserted that a default DRE would have to be used until a facility c ould complete new tests. The commenter suggested that DREs obtained from prior test ing should be permitted, provided that a facility can show that the testing methods us ed were substantially similar to the method

in the EPA DRE Protocol. The commenter also suggested that semiconductor processes that have been previously validated and tested by the abatement manufacturer should be exempt from additional emission testing fo r DRE re-validation, provided that the units are operated, ma intained, and serviced according to the manufacturer’s specifications.

Response 5.2.4-b: Facilities are allowed to use prev iously measured DREs. A facility may use previously measured DREs provid ed the facility can demonstrate that the

measurements were made in accordance with the EPA’s DRE Protocol. Facilities may demonstrate this by providing documentatio n of compliance with the principles and requirements of the Protocol.

See response to comments in section 5.2.4.2 for a discussion of the required use of the RSASTP. See the response to comment 5.2.3-c about using abatement system manufacturer supplied DREs for abatement syst ems that are prop erly installed, operated, and maintained in accordance with manufacturers’ specifications.November 2010 69 5.2.4.1 EPA’s DRE Protocol

Comment Summary 5.2.4.1-a: One commenter (0131) re stated its comments, and made some new comments on the EPA DRE Protocol made in a prior public peer review process and again urged EPA to accept them. The commenter also asserted that FTIR is already an acceptable approv ed EPA method (e.g., EPA Method 320, or EPA Method 301 validation) to characterize other air emissions without the need for additional analytic equipment (e.g., Quadrapole Mass Spectroscopy). Another commenter (0099) supported t hese comments as well.

Response 5.2.4.1-a : Most of the comments from commenter 0131 on the EPA DRE Protocol were previously submitted to EPA as part of the two public peer review processes EPA undertook for the DRE Prot ocol. EPA responded to these comments during that process. The comments and re sponses are available in the docket EPAHQ-OAR-2009-0927. The new comments co mmenter 0131 submitted on the DRE

Protocol are addressed in A ppendix B of this document.

The use of an FTIR without the use of additi onal analytical equipment, such as a QMS, is an acceptable means to measure DREs only in certain instances. EPA is allowing

the use of an FTIR without the use of a QMS in certain cases. In the DRE Protocol, EPA permits the use of an FTIR in place of a QMS when tracer gases, such as CF 4 and

SF 6 , are used in place of an inert gas to measure dilution (provided the abatement system which is being tested does not abate the tracer gas (CF 4 or SF 6 )). The DRE Protocol does not permit, howev er, the use of an FTIR in pl ace of a QMS for measuring

dilution with tracers that are inert because, although a method that uses FTIRmeasurable gases may become available, no robust in-fab measurements exist today

that demonstrate the veraci ty of such a method.

Comment Summary 5.2.4.1-b : One commenter (0112) re commended that EPA allow

facilities to use CF 4 as a tracer gas to determine di lution in abatement testing. The

commenter asserted that the use of CF 4 will offer flexibility to the facility performing the testing, since CF 4 destruction during low-fire temperatur es will be minimal, resulting in a conservative assessment of destruction efficiency.

Response 5.2.4.1-b: EPA does not wholly prohibit the use of CF 4 as a tracer in the DRE Protocol, and hence in the rule. Specif ically, with respect to measuring systems

that do not abate CF 4 and/or SF 6 , EPA’s DRE Protocol stat es, “In such systems, CF 4 or SF 6 can be used in place of an inert gas si nce their DREs are zero percent. Table 2 provides a list of acceptable gases for m easuring total abatement system flows, along

with their use conditions.” As discussed in this excerpt, EPA’s DRE Protocol does not permit the use of either CF 4 or SF 6 as tracer gases in abatement systems that are designed to abate these gases. EPA does prohibit the use of CF 4 as a tracer in fluorinated GHG abatement system s operating in “low fire” because reviewers of early drafts of EPA’s DRE Protocol made repeated claims that one could not be certain that

some abatement of CF 4 was not occurring, which would bias dilution and hence DRE

measurements. For more discussion on the use of CF 4 as a tracer gas please see theNovember 2010 70 responses to comments on the DRE Protoc ol, available in docket EPA-HQ-OAR-2009-

0927.

Comment Summary 5.2.4.1-c: One commenter (0112) proposed the use of a performance based standard, rather than a te chnology based standard, for testing of destruction unit efficiency. A performanc e based standard would be better able to accommodate evolving technology, such as nondispersive infrared sensor (NDIR), which may include those that are more cost effective and capable. The commenter asserted that proscribing an FTIR methodology for DRE testing limits the use of current and future improvements in monitoring technologies and will limit cost-effectively meeting EPA’s monitoring requirements.

Response 5.2.4.1-c: The final rule requires the use of the EPA DRE Protocol, which is based on the use of some technologies such as QMS or FTIR used to measure DREs, as opposed to other technologies such as NDIR which may be used to monitor the performance of abatement systems. The final rule does not sp ecifically prohibit or require facilities to use technologies such as NDIR to monitor the performance of abatement systems. Please see the respons es to comments on the DRE Protocol, available in docket EPA-HQ-OAR-2009-0927 for EPA’s previous response to

comments on the use of NDIR from the Protocol’s public peer review process.

5.2.4.2 Random Sampling Abatem ent System Testing Program

Comment Summary 5.2.4.2-a: One commenter (0112) s upported allowing facilities that have undertaken Random Sampling Ab atement System Testing Program (RSASTP) for abatement devices to use actual tested values on the tested units and the average destruction value for all other un its. The commenter asserted that this enables accurate representation of PFC gas emissions.

However, the commenter proposes the follo wing approach to testing and certifying the performance of abatement equipment as an al ternative that is less burdensome: “Facilities should be required to test 20 percent of the abatement flee t at a facility for the first two years of the repor ting requirements. If the two y ears of testing verifies that the abatement systems are per forming within 10 percent of the manufacturer’s specification, the facility should be allow ed to certify that its abatement devices are being maintained in accordance with a documented maintenance plan based on, but not necessarily in complete conform ance with, the manufa cturer’s recommended maintenance procedures, and reduce the test ing frequency as described below. In the third year and beyond, the facility shall per form a single test of a randomly selected abatement unit for each abatement system class to verify continued performance. This will provide the base data to demonstrate the current performance of abatement systems while enabling facilities to perform less frequent testing to demonstrate system performance in recognition t hat the properly maintained units are expected to perform to their specifications.”November 2010 71 Two other commenters (0099 and 0131) propos ed a similar, but less detailed, alternative approach to the RSASTP: a facility should instead be able to use the average DRE based on performance testing data. The commenters also propose: “A facility can provide test data for an abatement system class to certify annual emissions. Upon completion of two (2) years of random testing of at least two (2) abatement systems by class at a facili ty, the DRE by class should be able to be certified in subsequent years.” A commenter (0131) went on to state, “In addition, the facility would be expected to perform the r equired system maintenance.”

One of the commenters (0131) further asserted that periodic testing is not necessary when the facility operates abatement equipm ent properly. The commenter stated that where a device has been desig ned for GHG reduction, default factors reflect test data with sufficient accuracy, and thus testing should be required only for new models, not variants of existing systems.

Response 5.2.4.2-a: EPA appreciates one commenter’s support of the RSASTP. EPA considered the commenters’ suggested alter natives to the RSASTP; however, in the final rule EPA is maintaining that facilit ies using properly meas ured DREs must adhere to the RSASTP (see §98.94(f)(4). EPA devel oped the RSASTP, in the absence of data about abatement system time to fa ilure or DRE performance dri ft, to provide an efficient and relatively reliable device measurement scheme when compared to requiring a facility to test annually all abatement system s used. The RSASTP still allows EPA to ensure a facility has measured DREs accurate ly and at least once every five years. This is an essential part of the RSAST P because abatement system performance varies greatly depending on a variety of abatement device and process parameters such as temperature, flow, and exhaust composition. Faci lities develop and ultimately use new processes potentially every year, a nd the parameters of these processes vary. Given this, by requiring the gradual test ing and retesting of abatement systems over time through the RSASTP, EPA can ensur e properly measured DREs, and DRE class averages used at a facility will accurately re flect controlled emissions. Please see the preamble section D, Electronics Manufacturi ng (subpart I), section 3 (“Summary of Comments and Responses”), for the re sponse to comments on the RSASTP and

section 5.2.3 for details on the use of default DREs.

Comment Summary 5.2.4.2-b: One commenter (0122) noted that, for a facility under construction, the commenter plans to ut ilize approximately 200 POU abatement devices (some that do not solely abate PFCs). The co mmenter expected that for this facility, approximately three models of device wi ll be represented, depending on how the rule defines a “model,” because models often enc ompass multiple configurations. The commenter estimated testing costs for 20 per cent of these devices, in accordance with the RSASTP, to be in excess of $500,000 an nually. The commenter asserted this testing requirement is expensive and redund ant because (1) testing would serve to validate equipment with which industry has s ubstantial field experience, and (2) given

the small number of abatement equipment models expected to be deployed at a facility, multiple tests would be required to be done on the same abatem ent systems under theNovember 2010 72 RSASTP. The commenter indicated that, giv en these costs, a broader application of the default DRE factor may be expected, resu lting in emission over-estimates.

Response 5.2.4.2-b: EPA does not agree that t he RSASTP is expensive and

redundant. EPA has concluded that more in-f ab direct measurement of DREs, beyond what has already been done, is necessary, because, as shown in EPA’s DRE testing program, in some cases installed abatement system DREs for popular and difficult to abate gases like CF 4 and C 2 F 6 do not achieve guaranteed DRE provided by abatement manufacturers. The RSASTP provides a mu ch less burdensome device measurement scheme than requiring a facility to test all abatement systems used annually, but still allows EPA to ensure a facility has measur ed DREs accurately and at least once every five years. EPA has determined that this testing frequency is necessary for all abatement systems used, regardless of t he model, because the RSASTP anticipates reliable maintenance periods and useful lifetim es of abatement systems. Also, it is necessary to test every system used at a fa cility, regardless of the model of system,

because it is well known across the industr y that abatement system performance varies greatly depending on the type of abatement device and proc ess parameters such as temperature, flow, and exhaust composition. 36 As stated by many commenters, facilities develop and ultimately use new processe s potentially every y ear, and the parameters of these processes vary. Therefore, gradual testing over a five year period is not

redundant as DREs between the same abatem ent system models may vary between years depending on the process exhaust fed into the abatem ent systems, which may also cause RSASTP class average DREs to vary between years. See the preamble section D, Electronics Manufacturing (subpa rt I), section 3, for the response to comments on the RSASTP. See response to comments in section 5.2.3 on the application of default DREs.

Comment Summary 5.2.4.2-c: Two commenters (0123 and 0110) asserted that the frequency of required testing using the RSASTP is burdensome and unnecessary. Further, the commenters asserted that new abatement systems that are installed, operated, and maintained according to the manufacturer’s recommendations should not require annual testing.

The commenters believed the use of manufa cturer specified DRE values and less frequent testing was sufficient, because fa cilities may have a small number of abatement systems (e.g., facilities that have three abatement systems) and for new processes that become part of producti on, new abatement systems associated with these new classes could require annual te sting. For these types of facilities

commenters believed that inst ead of testing 20 percent or 3 abatement systems in each year as in the proposed RSASTP, that abatement systems be tested on a set schedule. One commenter (0123) proposed once every th ree years, and t he other commenter (0110) proposed testing a maximum of once every five years.

36 Beu, L. (2005). “Reduction of Perfluorocarbon (PFC) Emission s: 2005 State-of-the-Technology Report”, TT#0510469AENG, International SEMATECH M anufacturing Initiative (ISMI), December 2005. Available at: http://www.epa.gov/highgwp/semic onductor-pfc/documents/final_tt_report.pdf.November 2010 73 Response 5.2.4.2-c: EPA does not agree with commenter s who asserted the RSASTP is burdensome and unnecessary, provided abatement systems are designed and operated to abate fluorinated GHGs. EPA’s DRE provisions address the dearth of published data on abatement system DRE per formance for systems designed to abate fluorinated GHGs and the variability in t hose DRE values over time, under in-fab

conditions. Commenters did not provide EPA sufficient info rmation or data to mitigate concerns regarding the varying performanc e of abatement systems over time. See response to comment 5.2.4.2-b and s ee the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the response to comments on the RSASTP and discussion on why EPA is requiring the RSASTP. See also responses to comments in section 5.2.3 on why EPA is not allowing the use of manuf acturer specified DREs.

Comment Summary 5.2.4.2-d: One commenter (0089) assert ed that testing of 20 percent of units each year is burdensome at large fabricati on sites that may have more

than 100 individual devices in operation. Testing can negativel y affect manufacturing as

most tools would need to be ta ken offline during the testing period. As an alternative, the commenter proposed: “Destruction remo val efficiency testing should only be required on a representative por tion of identical POU devices. This initial testing can be used to characterize the key operating parameters (e.g., operat ing temperature, residence time, etc.) the device must meet in order to achieve the efficiency measured during the test. The unit, and similar units, can then be assumed to be achieving this efficiency as long as it can be documented that they are operat ing within the key parameters, without a need for ongoing testing. This approac h is consistent with the methods that state and local air pollution control agencies have used for years to establish DRE for control devices on other pollu tants. Intel has many control devices in place at its fabs to treat volatile organic compounds (VOCs) or hazardous air pollutants (HAPs). The DRE for those devices is typica lly established in a manner similar to that described above, without t he need for ongoing testing, or even for testing each

individual unit.” The commenter asserted th at EPA at least implicitly endorses this approach because the permits under whic h these sites operate are considered “federally enforceable” for purposes of ma intaining emissions below major source thresholds. Another commenter (0131) al so asserted that the testing frequency requirements are excessive and a cost burden given that EPA has not provided data to support annual testing beyond what is r equired for other EPA regulations.

Response 5.2.4.2-d: EPA does not agree with the comment er that testing 20 percent of units a year is an excessive burden for la rge facilities. EPA a cknowledges that tools do need to be offline for a portion of the time required for DRE testi ng, but it is not plausible that a facility will be running tools 100 percent of the available time. During downtime periods, abatement systems attached to such tools may be tested. Given that the RSASTP requires testing of an abatement syst em essentially once every five years, there should be points within that period where tools are offline that DRE testing can be done. Through EPA’s experience in the DRE measurement program, EPA has found that testing can be done within the constraint s of manufacturing environments and thatNovember 2010 74 manufacturing schedules can accommodate a period for testing without adverse

effects.

EPA considered the commenters’ suggested alte rnatives to the RSASTP; however, in the final rule EPA is maintaining that fa cilities using properly measured DREs must adhere to the RSASTP. See the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comm ents and Responses”), for the response to

comments on the RSASTP. Please also see response to comment 5.2.4.2-a and

5.2.4.2-b for more discussion on the required use of the RSASTP.

The testing frequency required through the RSASTP is aligned with the purpose and goal of the GHG Reporting Program which, in contrast to other regulatory programs with different goals, is to collect accurate facility-level GHG emission information to inform future policy and regulatory decisions . Please see response to comment 4.1.2-c for more discussion on the relationship bet ween this rule and air quality regulations.

Comment Summary 5.2.4.2-e: One commenter (0095) noted that it is not clear

whether the RSASTP is in tended to include only proce sses that have not yet gone through emission testing, or if it also incl udes processes that have already been tested. The commenter suggested that semiconductor processes that have been validated and tested by the abatement manufacturer should be exempt from additional emission testing for DRE re-validation, provi ded that the abatement units are operated, maintained, and serviced according to the manufacturer’s specification.

Response 5.2.4.2-e: EPA is not permitting the use of measurements made previously by an abatement system manufacturer, as di scussed in response to comment 5.2.4.2- b. EPA is permitting only measurements made at a facility using the EPA DRE Protocol

to be used to account for the use of abat ement systems. EPA is allowing the use of

these measurements if a fa cility has conducted DRE measurements using the EPA DRE Protocol published in March of 2010. Please see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the response to comments on the RSASTP.

5.3 Other QA/QC Procedures

Comment Summary 5.3-a: One commenter (0112) as serted that EPA needs to provide more flexibility for facilities to dev elop inline calibration pr ocedures for PFC gas flow measuring devices. The commenter stated that most of the mass flow controllers purchased have guaranteed performance accu racy within 1 percent. The commenter

asserted it would be better if flow calib ration was run less frequently and while the meters were installed on the tool; re moving each mass flow controller for bench calibration introduces significant costs, downtime, and contam ination exposure.

Response 5.3-a: In the final rule, EPA has remo ved the calibration requirement proposed in §98.94(i) (75 FR 18702, April 2010) because the calibration aspects of the

2006 ISMI Guidelines and the EPA DRE Protocol are sufficient for purposes of the rule.November 2010 75 Comment Summary 5.3-b: One commenter (0131) assert ed that scales and pressure monitoring devices are not currently calib rated per ISO 9000 Quality Standards, NIST traceable standards, or other me thods that would be considered “true calibration.” In many cases, calibration of a measurement device would require removing it from service and possibly disconnecting it from the tool. The comm enter asserted that this is unacceptable because facilities operate c ontinuously and are subject to rigorous

contamination control for replaced or removed equipm ent. Currently, performance

verification is conducted on measurement dev ices as needed since the trigger point for change-out is a highly critical measurement to ensure that the integrit y of gas delivery is not compromised.

Response 5.3-b : Please see response to comment 5.3-a for information on how EPA addressed calibration require ments in the final rule.

Comment Summary 5.3-c : One commenter (0089) suggest ed that the requirement for facilities to follow QA/QC procedures in the 2006 ISMI Guidelines and in EPA’s DRE Protocol should be applicable only from the effective date of t he rule forward. Facilities should not be required to retroactively s how compliance with these procedures for measurements or testing done prior to the publication of the rule.

Response 5.3-c: This rule is not retroactive. This rule does not impose any new liability or obligation on the basis of past conduct and its emission reporting requirements are prospective only. For facilities to use historical emissions measurements, they must s how compliance with QA/QC pr ocedures for the appropriate ISMI Guidelines. EPA needs to verify t hat appropriate QA/QC procedures were followed for any measurement s made and factored into emission estimation methods, regardless of when the measur ements occurred, to ensure t he quality of the data being used to estimate emissions. In general, EPA designed these requ irements with the expectation that the measur ements would be made in future, because according to an industry survey the majority of semiconduc tor manufacturers have not performed Tier 3 measurement testing. 37 However, to provide more flex ibility for facilities that have already made Tier 3 measurements prior to the publication of the rule, EPA is allowing facilities to use measurements made in the pas t if sufficient supporting documentation is available. In the final rule EPA is pe rmitting facilities to use measurements made in accordance with not only the 2006 ISMI Guidel ines, but the 2001 ISMI Guidelines as

well. For facilities to use historical meas urements made with the 2001 ISMI Guidelines, EPA is requiring facilities to document that the QA/QC procedures from the 2001 ISMI

Guidelines were followed. Please see res ponse to comment 5.1- a for details on the required use of the 2001 or 2006 ISMI Guidelines.

Because the DRE Protocol was published recently (2010), in general EPA assumes that the first year of data colle ction for this rule would corre spond to the first year of the

37 EPA is also unaware of any other type of elec tronics manufacturer (MEM S, LCD, PV) that have performed Tier 3 measurements.November 2010 76 RSASTP for many facilities. However if t here are instances wher e a facility has DRE measurements made prior to the effective date of a rule, but within the time span of the required RSASTP (5 years) the facility w ould be permitted to use those measurements provided sufficient documentation is availabl e to show that the QA/QC procedures in the DRE Protocol were followed, and t he measurements were made using EPA’s DRE

Protocol.November 2010 77 

### 6. Data Reporting Requirements

Many comments on data reporting and confident ial business information (CBI) were interrelated. Responses to comments ma y appear in this section 6 (Data Reporting Requirements) or in section 9 (Conf idential Business Information).

Comment Summary 6-a: With respect to EPA’s propo sed requirement in §98.95(g) (that a facility calculates and reports the facility-wide co nsumption of gas based on the modeling calculations perfo rmed using engineering and pr ocess data), one commenter (0112) proposed that the requi red reported data be moved to recordkeeping. The

commenter asserted that the calculations ha ve a degree of uncertainty due to process and measurement variation, and thus the calc ulations will not directly match actual usage. The commenter stated t hat there is no reason to r eport this data and that the facility should maintain the data and have it available for inspection and discussion.

The commenter also stated t hat the model will need to us e statistical methods to reconcile use calculations based on proc ess and fab data to actual gas use as determined by cylinder di sbursements.

Response 6-a: With respect to the commenter’s r equest that a facility should maintain data on the modeling calculation perform ed using engineering and process data as a recordkeeping requirement and not be required to report such data, this requirement as proposed is not being finalized in this rule. EPA has modified the procedures by which facilities are required to develop gas consumpt ion apportioning factors, and is requiring that facilities submit to EPA specific information on the model (see §98.94(c))

. The information that EPA is requiring facilities to submit about facility-specific engineering models to apportion gas consumption will provi de EPA with data to verify the models. Thus, it is important that this information be reported to the Agency. For additional comment responses on the facility-specific engineering model, please see also the preamble section D, Electronics Manufacturi ng (subpart I), section 3 (“Summary of Comments and Responses.”)

Comment Summary 6-b: One commenter (0089) asserted that submitting results of all

test data for the Tier 3 approach is an unnecessary burden, and would likely provide

EPA with more data than it can review. The commenter noted that a single fab may

have 100 or more individual tool tests co vering all processes steps and all covered fluorinated gases. In addition, the commenter asserted that this type of information is confidential business information (CBI). T he commenter proposed t hat facilities that use the Tier 3 approach submit data on chem ical use, emissions factors used, and a detailed summary explaining methods for apportioning chemical use amongst process steps with supporting documentati on. The commenter proposed that actual copies of emission tests be maintained on site and available for inspection. These methods would be consistent with requi rements for verifying emissi ons of regulated pollutants with state and local agencies.November 2010 78 Response 6-b: Although EPA is unsure exactly to which state and local agency requirements the commenter is referring, in contrast to ot her regulatory programs, this rule focuses on establishing each facility’s annual GHG emissions in tons per year, not on whether a facility's emissions are below a specified limit. EPA considered reporting and recordkeeping requirements (s ee §98.96 and §98.97) and strived for a

balance between information that is critic al for analyzing and verifying reported emissions and minimizing reporting burden.

EPA concurs with the commenter ’s suggestion that the det ailed Tier 3 emission

measurement documentation should be retained onsite for inspection. EPA is requiring facilities to report data on gas usage, em ission factors (utilization and byproduct formation rates), the type of film and feature t hat was etched, the source of the

emission factor information fo r that recipe, and certificat ion that the measurements were made using the 2006 ISMI Guidelines , or the 2001 ISMI Guidelines if measurements were made prior to January 1, 2007. Other information including

documentation that measurements were ma de using the ISMI Guidelines must be retained as records. EPA is requiring reporting, rather than simply re tention, of certain data in order to permit EPA to conduct an annual verification of the emissions quantities 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 frequen cy of verification would be lower,

while the costs of such verification would be much higher. Nonet heless, EPA is aware of the commenters’ concerns and may consi der moving certain re quirements from the reporting section to the recordkeeping sect ion of the rule following further analysis.

With respect to the commenter ’s concern that Tier 3 test data is CBI, today’s action does not address whether data reported under subpart I will be treated as CBI. EPA is addressing CBI issues in a separate rulemaking. EPA published a proposed confidentiality determination on July 7, 2010 (75 FR 39094) which addressed the CBI

status of certain data elements. In t hat action, EPA proposed which specific data

elements would be treated as CBI and which data elements must be available to the public under section 114 of the CAA. EPA has received comments on the proposal and is in the process of considering these co mments. A final dete rmination will be issued before any data is released, and the final determination will incl ude all of the data elements under these subparts. (For more information on the CBI rulemaking, please

see, http://www.epa.gov/climatechange/ emissions/CBI.html#proposal ).

Comment Summary 6-c: One commenter (0099) propos ed that EPA only require

facilities to submit annual emissions and the method of emissi ons calculations. Facilities would keep all other data element s on site and available for inspection. The commenter asserted, “this is consistent with management of t he underlying emissions

calculations data in other ai r quality and permitting programs.”

Response 6-c: EPA does not agree with the commenter that it should only require

facilities to submit annual emissions and the me thod of emissions calculation. Although EPA is unsure exactly to which other air quality and permitting programs theNovember 2010 79 commenter is referring, in contrast to ot her regulatory programs, this rule focuses on establishing each facility’s annual GHG emissi ons in tons per year, not on whether a facility's emissions are below a specified limi t. EPA is requiring reporting, rather than simply retention, of certain information relating to the emissions calculation to permit EPA to verify the data reported by each fac ility. Since emission factors can vary significantly between processes, and hence fac ilities, it is import ant for EPA to have a high degree of granularity in r eported emissions information to facilitate verification and evaluation of individual components of a reported emission estimate. 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, wh ile the costs of such verification would be much higher. Nonetheless, EPA is awar e of the commenters’ concerns and may consider moving certain requirements from the reporting section to the recordkeeping section of the rule following further analysis. Please see Response 6-b for additional response to comments on data r eporting requirements.

Comment Summary 6-d: One commenter (0095) request ed clarification on whether production based on substrate area is based on the total number of fully processed

wafers or on the number of wafer starts. The commenter requested this clarification

because it asserted that certain semiconducto r companies that appear to be covered by subpart I do not manufacture wafers and pr ocess wafers, but only partially process

wafers for research and development (R&D) purposes.

Response 6-d: EPA is requiring semiconductor manufactu ring facilities to use their full facility design capacity, in terms of substrate surface area (e.g ., silicon), in the threshold

determination calculation which is based on the 2006 IPCC Tier 1 method. 38 Under this approach, a facility’s potential to emit determi nes whether the facility meets or exceeds the reporting threshold. As a result of using a facility's full annual design capacity in terms of substrate surface area, the distinct ion between processed wafers and partiallyprocessed R&D wafers is not relevant to t he threshold analysis. For data reporting, EPA is requiring facilities to provide the total substrate surface area processed. However, if the partial wafer processing wa s associated with R&D activities (as defined in 40 CFR 98.6), that subs trate area should not be repor ted to EPA. Please see comment response 1-b for responses to comment on R&D activities.

Comment Summary 6-e: Two commenters (0089 and 0112) requested that annual surface area production be removed from r eporting requirements because it is CBI and it does not actually affect emission results.

Response 6-e: EPA acknowledges the commenter’s suggestion to shift annual substrate area processed per y ear from the reporting to the recordkeeping provisions. EPA carefully considered reporting and reco rdkeeping requirements and strived to

balance its need for information that is cr itical for analyzing and verifying reported

38 See the preamble to the final rule for more in formation about the reporting threshold determination

calculations.November 2010 80 emissions and the goal of minimizing reporti ng burden. EPA determined that a facility's annual substrate processed is an important manufac turing activity datum and that it should be retained as a data reporting requirement. Receiving this data will enable the Agency to track facility level emission intens ity trends, identify reporting anomalies, and develop future GHG policies and programs. EPA is requiring r eporting, rather than just retention, of certain data to allow EPA to annually verify the emission quantities 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 frequen cy of verification would be lower,

while the costs of such verification would be much higher. Nonet heless, EPA is aware of the commenters’ concerns and may consi der moving certain re quirements from the reporting section to the recordkeeping sect ion of the rule following further analysis.

In regards to the commenter’s assertion that substrate surface area processed is considered CBI, today’s action does not addr ess whether data reported under subpart I

will be treated as CBI. Please also see comm ent responses in 6-b. Please also see comment responses in section 9 on CBI.

6.1 DRE Reporting

Comment Summary 6.1-a: Two commenters (0099 and 0131) were concerned that the proposed rule would require semicondu ctor manufacturers to generate a large amount of information pertaining to the abatement systems used at a facility for

fluorinated GHG control. T he commenters asserted that th is requirement would prove quite costly and burdensome.

Response 6.1-a: To comply with the final rule requirements for reporting controlled emissions, facilities may have to generate new information pertaining to the use of abatement systems each year, and EPA recogni zes that there is some associated burden. However, EPA has det ermined that such information is essential to verify reported controlled emissions.

For example, abatement system installation , maintenance, and testing are critical components of DRE performance. Therefor e, it is important from a reporting perspective to ensure that proper documentation is devel oped and retained that would support the reported emissions of a given fa cility. In addition, information about

abatement devices used at an electronics m anufacturing facility will enable EPA to track emission trends from the industry to develop future GHG policies and programs.

Much of the documentation for using either the EPA default DRE or properly measured DREs can be efficiently developed and stored by reporting entities. For example, the DRE Protocol contains a simple and repeat able example template for certifying the measurement results. In addition, the bulk of the information r equired for abatement system certification and monitoring is a reco rdkeeping requirement that can efficiently be accomplished through electronic file (e.g ., Microsoft Word or Excel and Adobe PDF) management and storage.November 2010 81 In addition, it is important to note that as a means to balance burden EPA has provided facilities with the option of reporting det ailed information on measured DREs or using EPA’s default DRE, the latter of which will require less information to be reported to

EPA.November 2010 82 

### 7. Records that Must be Retained

Comment Summary 7-a: One commenter (0112) assert ed that invoices for gas purchases should only be required to be reta ined for 3 years. Longer retention times are unreasonable and likely to conflict with company internal recordkeeping requirements.

Response 7-a: EPA appreciates the commenter’s concern regarding the length of

record retention. Consistent with the Final M RR, under this rule facilities are required to retain records for three years. As EPA stat ed in the preamble to the Final MRR, “a three- year time period is sufficient to allow for EPA to audit and review of records needed to verify the emission data submitted in annual reports” (74 FR 56281, October 2009). It is important to not e, in that final rule, EPA reduced the record retention requirements from five (as pr oposed) to three years. Pleas e see the preamble to the Final MRR for responses to comments on re cord retention (74 FR 56281, October 2009).

Comment Summary 7-b: With respect to EPA’s requirement for facilities to maintain records for testing done at a facility, in cluding documentation to demonstrate that

emissions measurements were made us ing the 2006 ISMI Guidelines and

documentation that DREs were measured in accordance with EPA’ s DRE Protocol, one commenter (0089) suggested that these re cord keeping requirements should not apply retroactively. The commenter asserted that facilities that have conducted emissions measurement tests prior to the publication of the rule would be unable to comply. The commenter argued that this requirement woul d disallow the use of any measurements

made before the effective date of the rule. The commenter expressed a similar concern regarding obtaining certificat ion about the design purpose for abatement systems, citing

that facilities would have to assume a DRE of zero if retroactive certification were required. (Note, in a similar regard, t he commenter also asse rted that the testing requirements for emissions characterization and DRE testing should only be applied to measurements going forward. Please see co mment responses 5.1-a and 5.2.4-b for responses to comments on the required us e of the EPA DRE Protocol and the ISMI Guidelines).

Response 7-b: This rule is not retroactive. It does not impose any new liability or obligation on the basis of past conduct and its emission reporting and recordkeeping requirements are prospective only. This rule does not require any facility to take into account reductions achieved by its abatement system in reporting its GHG emissions. To the extent a facility chooses this opti on, the facility may choose to use the default DRE or a properly measured DRE (i.e., DREs measured in a ccordance with EPA’s DRE Protocol). Only in the latter instance must the facility maintain as a record a

certification that t he DRE was calculated according to methods in EPA’s DRE Protocol. The other requirement referred to by the commenter applies only to facilities using facility-specific, recipe-specif ic utilization and by-product formation rates. In general, EPA designed these requirements with the expec tation that the measurements wouldNovember 2010 83 be made in the future. However, to provide more flexib ility, EPA is allowing facilities to use measurements made in the past if sufficient supporting documentatio n is available.

EPA is not permitting emission factor and DRE measurements that have not been made in accordance with the requirements fina lized in the rule to be “grandfathered” in as the commenter suggested. EPA’s final rule allows a facility to document and use

historical emission measurem ent results provided the m easurements were made using the 2006 ISMI Guidelines (or the 2001 ISMI Guidelines for measurements made prior to January 1, 2007) and abatement system DRE measurements, if made in accordance

with the EPA DRE Protocol. If misplaced, the facility may have to locate historical test plans, log books, and other information perta ining to the measurement studies. With regard to the certification of design pur pose for abatement system s where the default DRE will be used, this is a critical co mponent of the DRE validation process. EPA

understands that coordination with the abatement system vendor to obtain necessary documentation may be required. If the facility cannot obtain documentation that

demonstrates that an abatement system is designed to destroy fluorinated GHGs

and/or N 2 O, then the facility cannot claim a reduc tion in emissions. If an abatement system vendor is claiming a DRE for a giv en system, then the vendor should be able to produce a system design certification. There is nothing retroactive about this requirement. EPA is not stating that the v endor must have prepared such a certification at the time of sale; the facility may request that the vendor prepare such a certification so that the facility may take advantage of the default DRE option under this rule. Please also see response to comments 5.1-a and 5.2.4-b on why EPA is requiring

measurements to be made usin g the ISMI Guidelines an d EPA’s DRE Protocol.November 2010 84 

### 8. Cost Data/Burden

Comment Summary 8-a: One commenter (0124) asserted that the reporting burden for the electronics industry is still a concern. Reporting costs for th e first year for the electronics manufacturing industry, $0.51 per MtCO 2 e, are higher than EPA’s estimated average cost for all s ources, $0.04 per MtCO 2 e. The commenter al so asserted that due to the high GWP of many gases used in t he electronics manufacturing sector and other fluorinated GHG-using sectors, facilities with small amount s of actual emissions may become subject to repo rting under the MRR.

Response 8-a: EPA acknowledges certain sectors face different reporting costs per ton. EPA estimates the average reporting co st for the electronics manufacturing industry to be $0.51 per ton. The wide variety of potent and often long-lived GHGs used by this sector naturally adds complexi ty to the monitoring and reporting methods. The cost per ton provides a comparison to other subpart in t he mandatory reporting rule. While in some cases the per ton r eporting costs are higher than other subparts, the overall goal of the GHG reporting is to provide a comprehensive and accurate reporting system. The cost effectiveness metric of cost per ton r eported may not be the most appropriate means to evaluate the econom ic impact of the rule and is just one means of doing so. Another metric presented in the EIA is cost-to-sales ratios, which evaluates the compliance cost against average receipts for like facilities. EPA found the cost-to-sales ratio for this industry to genera lly be below 1 percent. More detail on this analysis is available in the Economic Impact Analysis in Section 5.3.1.

Comment Summary 8-b: One commenter (0112) assert ed that the proposed rule would cost the company $3-5 m illion in capital investments if major changes had to be made to estimate and apportion gas consumpti on. The commenter stated “that it will require $3-5 million in capital investment if major changes have to be to distribution and/or metering systems to segregate distribut ion systems by process type and to meet the 1% accuracy requirement for measurem ent systems. Annual o perating costs could approach $1 million per year when including t he cost of testing 20 percent of the emissions abatement devices, as our EFK fa cility will have over 200 abatement units

installed.” The commenter al so asserted that “in aggregate, the rule drives capital investments of $1.5 milli on to $5 million and between $500,000 and $2,000 for ongoing operation and maintenance cost to comply wit h the requirements in the re-proposal of the GHG reporting rule for ‘Additional Sources of Fluorinated Gases’.”

Response 8-b: In the final rule, EPA has made efforts to balance burden to the industry while maintaining requirements that EPA has determined are necessary to obtain facility-specific emission estimate s. Please see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the responses to comment s which discuss burden-reducing efforts.

Although the commenter assert ed that the proposed rule w ould result in significant costs, the commenter did not provide details on how their costs were estimated. EPA has updated the Economic Impact Analysis (EIA) to reflect the requirements finalized inNovember 2010 85 the rule. For example, EPA has now included capital costs associated with apportioning gas consumption. For details on how EPA developed its final costs for this rule, see sections 4 & 5 of the EIA (a vailable in the docket, EPA-HQ-OAR-2009-0927).

Please see response to comments in secti on 4.1.1.1 for a discussion on the accuracy and precision requirements in the final rule.

EPA is mindful of the costs associated with reporting controlled emissions by properly measuring the DRE of the abatement systems in accordanc e with EPA’s DRE Protocol (the approach for which the commenter is basi ng their cost estimate s). As a burdenreducing measure EPA has prov ided the RSASTP, which requires a facility to test 20 percent of its abatement syst ems in each reporting year, as opposed to requiring a facility to test every abatement system in each reporting year for properly measuring abatement system DREs. EPA estimates that the costs associated with properly measuring abatement system DREs would be $70,000 per year for a facility. This estimate assumes that a facility has 50 abat ement systems total, and hence is testing 10 systems a year to comply with the RSAST P, where 5 systems can be tested in a week and one week of testing costs $35,000. This cost estimate is based on EPA experiences actually measuring the DREs of operational abatement systems. The cost EPA estimated for optional proper DRE meas urement will vary, however, depending on the number of abatement systems a facility has . As another means to reduce burden associated with reporting contro lled emissions, EPA has provided a default DRE factor that facilities may opt to use instead of properly measured DREs. 39 EPA has estimated that using the EPA default value is less co stly than properly measuring the DRE of abatement equipment in accordance with EPA’s DRE Protocol.

Comment Summary 8-c: One commenter (0122) estimat ed that testing 20 percent of abatement devices expected to be used at a fa cility currently under construction, to comply with the requirement s of the RSASTP, would co st in excess of $500,000 per year. The commenter asserted that this testing would be unnecessarily expensive, highly redundant, and carry a signific ant cost and burden without corresponding benefits of improved data accuracy or reduc ed emissions. The commenter expected that given these costs, a br oader use of default DRE factors would be seen, resulting in

an over-estimation of emissions. The comm enter asserted that the proposed rule as written presents challenges for a company that is currently making significant

investments in emission reductions on a vol untary basis. The commenter indicated that the recordkeeping burden is excessive gi ven the complexity of semiconductor manufacturing, the relatively low GHG emis sions compared to the whole economy, and the industry’s long history of pr oactive GHG emission reductions.

39 To report controlled em issions using the EPA default DRE value of 60 percent, a facility must certify that the abatement system for which they are report ing controlled emissions is installed, operated, and maintained in accordance with the manufacturers’ spec ifications. In addition, the facility must also obtain documentation from the abatement sy stem supplier certifying that the abatement system is specifically designed to abate fluorinated GHG and N 2 O.November 2010 86 Response 8-c: EPA disagrees with the commenter ’s statement that the RSASTP would be highly redundant and w ould provide limited improvem ent in data accuracy or

reduced emissions. EPA has concluded that t here is a need for gradually testing all of the abatement systems within a single class of abatement systems and for retesting individual abatement systems over time. As EPA stated in the preamble to the April 2010 proposed rule (75 FR 18652, April 201 0), some fluorinated GHGs, such as CF 4 , are harder to destroy than others; thus, the performanc e of abatement systems with one fluorinated GHG cannot be assumed to apply to other fluorinated GHGs. It is well known across the industry t hat abatement system per formance varies greatly depending on the abatement devic e and process parameters su ch as temperature, flow, and exhaust composition. Abatement system performance is also highly dependent on effective maintenan ce. By requiring the gradual testing and retesting of abatement systems over time through t he RSASTP, EPA can ensure properly measured DREs, and DRE class averages used at a facility will accurately reflect

controlled emissions.

Also, through the use of the RSASTP, EPA is reducing burden, for instance, for facilities that continually modify their processes. EPA is basing the RSASTP around classes, defined as abatement systems gr ouped by manufacturer model number(s) and by the gas which the system is used to abat e; varying process parameters, such as flows, temperature, an d exhaust composition, do not fact or into the requirements of the RSASTP. EPA has provided facilities with the flexibility to use a default DRE value of 60 percent as a less burdensome option for r eporting controlled emissions. (see section 5.2.3 for more discussion on the EPA default DRE.) EPA has included the cost

associated with DRE measurem ent testing in the EIA. For details on how EPA developed its final costs for th is rule, see sections 4 & 5 of the EIA (ava ilable in the docket, EPA-HQ-OAR-2009-0927).

EPA appreciates its industry Partners’ effo rts to reduce emissions under the PFC Reduction/Climate Partnership for the Semi conductor Industry, and EPA disagrees that this rule presents challenges for a company that is currently making significant investments in emission reductions on a voluntary basis. The rule is aimed at gathering accurate facility-level information, and gat hering this information does not inhibit a company from reducing emissions or account ing for those controlled emissions in GHG reporting.

EPA acknowledges the commenter’s concerns about the burden of data reporting and recordkeeping under the rule. EPA carefully considered reporting and recordkeeping requirements and strived for a balanc e between reporting burden and the need for information that is critical for analyzing and verifying reported emissions (see §98.96 and §98.97). Because emission factors can vary significant ly between processes, EPA is requiring a high degree of granularity in reported emissi ons information to facilitate

verification and evaluation of individual co mponents of an emissions estimate. EPA has determined that each piece of information required to be reported or retained as a record is directly relevant to the development of reporte d emissions.November 2010 87 Comment Summary 8-d: One commenter (TRANS-DC-02- 4) expressed appreciation that the proposed rule allows for an em ission factor approach and is responsive to suggestions to allow gas usage heel fa ctors based on cylinder-change triggers. However, the commenter indicated the propos ed rule may impose an equal or greater burden compared to the original due to gas a ccounting in the nine process categories

and N 2 O. Additionally, the commenter noted t hat the reporting scheme may impose significant compliance burdens and costs due to necessary quantifiable indicators and the disqualification of engineering judgment.

Two other commenters (0123 and 0110) asserted that the EIA of t he proposed rule shows a misunderstanding of current industry practices and data colle ction capabilities, severely underestimating the fiscal impacts . Specifically, the commenters raised concern with EPA’s assumptions that informa tion required by the Refined Method (i.e., gas consumption data and indicators of activi ty used to apportion gas consumption) is collected as part of BAU operations and that no capital costs are associated with rule compliance.

Response 8-d: EPA thanks the commenter for noting appreciation of the efforts EPA had made to balance burden for estimating gas consumption for the industry.

Although the EPA has not at this time fina lized the Refined Method, which is based on nine process sub-types for esti mating fluorinated GHG emissions, 40 the methods in the final rule (the Tier 2c and the Tier 2d) are similar to the Refined Method in that gas consumption must be estimated and apporti oned to process types, sub-types, or recipes. EPA therefore considered the comm enters’ concerns that gas consumption and apportioning compliance costs for the Refi ned Method were underestimated in the proposed EIA. EPA revised the cost esti mates for apportioning gas consumption for the final EIA to account for capital cost s associated with tracking information to apportion gas consumption. EPA has conc luded that its final cost estimates appropriately account for the compliance burden under this rule. Please see sections 4 & 5 of the EIA (available in the docket, EPA-HQ-OAR-2009-0927) for more details on the cost estimates and analysis.

The revised cost estimates represent the costs of the methods that fa cilities must use to apportion gas consumption in the final rule. T he finalized methods are flexible, allowing facilities to develop apportioning factors bas ed on a quantifiable metric of the facility’s choosing, provided the method is described in writing, is repeatable, and is verified through comparison with actual gas consumpt ion. This approach provides facilities flexibility in the choice of apportioning meth ods, thereby allowing facilities to develop

what will be their most cost-effective approach, and assuring the high degree of data quality that EPA needs. Pleas e see response to comment 4.1.2-a for more details on the revised gas apportioning methods and the preamble section D. Electronics Manufacturing (subpart I), section 3 (“Summa ry of Comments and Responses”), for

40 Please see response to comments in section 4.1.1 on the Refined Method and the preamble section D, Electronics Manufacturing (Subpart I), section 3 (“ Summary of Comments and Responses”), for a more detailed response to comments on emission estima tion methods for semiconductor facilities and apportioning gas consumption.November 2010 88 additional discussion on EPA’s responses to comments regarding burden for apportioning methods.

Comment Summary 8-e: Five commenters (0099, 0110, 0122, 0123, and 0131) asserted that the rule puts U. S. companies at a disadvant age globally because of the high associated costs. One comm enter (0123) asserted that rela tive to this competitive disadvantage, there is little environmental benefit. Another of th e commenters (0099)

states that the burden imposed by the rule may put pressure on U.S. companies to

move overseas.

Response 8-e: While EPA appreciates the global competition inherent in the electronics industry, the Agency is establis hing a reporting program with sufficient rigor as to allow for accurate quantification of U.S. GHG emissions to inform policy and regulatory decisions. From a global perspective, GHG emission inventory development and mitigation are priorities, and have been for m any years in countries such as Japan and the European Union. Other key electronics manufacturing nations such as Taiwan and China actively view GHG emission in ventory development and mitigation as important policy initiative s. Please see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the responses to comments which discuss burden-reducing efforts.

Comment Summary 8-f: One commenter (0089) supported accurate reporting of GHG emissions, but stressed that it is imperativ e to accomplish the reporting in a manner that does not result in unnecessary bur den, especially when more streamlined approaches can produce comparable accuracy.

Response 8-f: EPA considered all comments a ssociated with burden, and evaluated alternative methods for calculating cont rolled and uncontrolled GHG emissions for electronics manufacturing. EPA carefully ex plored alternative methods that would result in reduced burden on industry while ensuring the quality and breadth of reported data. In this final rule, EPA has made ever y effort to reduce burden to the industry while maintaining requirements necessary to obt ain facility-specific emission estimates. For example, based on comments received, EPA revised the gas apportioning method to allow for the usage of quantifiable indicato rs other than wafer passes. As another

means to reduce burden to the industr y, EPA is requiring only the “largest” semiconductor manufacturing facilities to ca lculate and report emissions using directly measured recipe-specific emission factors, ensuring that burden is commensurate with potential to emit. In addition, the largest semiconductor manufacturing facilities are only required to directly measure etching proc ess emissions. Only facilities that manufacture semiconductors using wa fers measuring greater than 300 mm are required to use recipe-specific emission fact ors. This requirem ent takes advantage of the opportunity, consistent with historical indu stry practices, reflected in International Technology Roadmap for Semiconductors (ITRS) 41 , to move the industry forward in

41 ITRS (2010) International Technology Roadmap for Semiconductors 2009 . This and earlier editions and updates are available at http:// www.itrs.net/Links/2009ITRS/Home2009.htm.November 2010 89 terms of emission estimation practices. As operations are being upgraded and constructed, consistent, robust, and accura te emission estimation practices can be established, and costs for these practices c an be incorporated into BAU operating costs for a facility.

In general, while commenters characteri zed EPA’s proposed requirements as burdensome and costly, the comments lack ed sufficient quantitative detail or substantiation. However, in response to concerns that EPA did not fully account for compliance costs in its economic analysis, EPA did update its costs estimates to reflect

the costs associated with the requirements finalized in the rule. EPA has concluded

that its final cost estima tes appropriately account for the compliance burden under this rule. For details on how EPA developed its final costs for this rule, please see sections 4 & 5 of the EIA (available in the docke t, EPA-HQ-OAR-2009-0927). Please also see the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for additio nal discussion on EPA’s responses to comments regarding burden.

Comment Summary 8-g: One commenter (0131) cite d the 2010 ISMI survey and stated that the semiconductor industry woul d incur an estimated $2.6 million in capital expenditures and $22 million in annual labor and operations and maintenance costs for apportioning gas usage according to refined process categories.

Response 8-g: Please see response to comment 8-b and 8-d for a discussion on costs

associated with the final rule and sections 4 & 5 of the EIA (available in the docket, EPA-HQ-OAR-2009-0927). EPA not es that the commenter di d not provide sufficient

information on how the cost and burden estimate s were developed. It is unclear to EPA how ISMI’s survey respondents developed cost estimates for their facilities. See the preamble section D, Electronics Manufacturi ng (subpart I), section 3 (“Summary of Comments and Responses”), for additio nal discussion on EPA’s responses to comments regarding burden.

Comment Summary 8-h: One commenter (0131) stated that for the semiconductor industry, migrating away from using def ault heel factors and meeting specific gas consumption tracking requirements would caus e the industry to incur significant costs that are higher than EPA-estima ted costs. The associated co sts would be in excess of $3 million per year in labor and operations and maintenance costs and $3 million in capital expenditures in gas usage cons umption tracking requirements. Two commenters (0110 and 0123) indicated concerns over capital costs associated with estimating gas-specific heel factors using equipment with an accuracy and precision of 1 percent of full scale or better.

Response 8-h: EPA understands that facilities may incur a cost to estimate gas consumption using the methods prescribed in the rule; however, EPA has made efforts in the final rule to balance the burden impos ed on facilities with EPA’s goal of obtainingNovember 2010 90 accurate, facility-level data. For more details on burden please see response to

comment 8-b and 8-d for and sections 4 & 5 of the EIA (availabl e in the docket, EPAHQ-OAR-2009-0927). Please see responses to comments in section 4.1.1 for EPA’s responses to comments regarding heel fact ors. See the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for additional discussion on EP A’s responses to comments regarding

burden.

Comment Summary 8-i: Two commenters (0099 and 0 131) cited the 2010 ISMI survey and stated that the semiconductor in dustry would incur costs of $7 million annually for compliance for abatement systems (not including lost production time), instead of the $1.61 million estimated by EPA. The commenters stated that this higher

estimate results from an esti mated cost of $242,000 per facilit y, in comparison to EPA’s estimate of $70,000 per facility. The commenters also assumed that 29 facilities employ

abatement devices and will have to incur th ese costs, as opposed to the 23 facilities

which EPA assumed.

Response 8-i: In the final EIA, EPA revised the assumption about the number of large facilities from 23 to 29, per the comment er’s suggestion. Please see response to

comment 8-b and 8-d and sections 4 & 5 of the EIA (available in the docket, EPA-HQOAR-2009-0927). Please see response to co mment 8-b for more discussion about the

estimated DREs costs associated with the rule.November 2010 91 

### 9. Confidential Business Information (CBI)

Comment Summary 9-a: One commenter (0131) asserted that the industry considers GHG usage and emissions by process to be highly confidential and sensitive. GHG usage and emissions by process can give aw ay confidential info rmation about device design and manufacturing processes. Two co mmenters (0099, 0131) a sserted that this information, in conjunction with production information for a facility, may cause inappropriate characterization of a facilit y’s manufacturing proc esses. One of the commenters (0131) argued that the information EPA is requiring to be reported under subpart I “does not constitute ‘emissions data, ’ as it is not necessary for determining emissions, given the availability of other , less intrusive means to do so.” The commenter went on to argue t hat there is no defin ition of “emissions data” under the GHG MRR, and “accordingly, the only two f ederal cases to have squarely addressed the meaning of ‘emission data’ under the C AA have held that the term ‘necessary to determine’ emissions is to be defined narrowly to include only data actually required to

determine emissions. Data are not necessa ry to determine emissions, and therefore are not ‘emission data,’ if other methods of determining emissions that do not require the disclosure of CBI are available.” Lastly, the commenter argued that the information EPA is requiring to be reported under subpart I is within the realm of information to be treated as CBI under EPA regulati ons at 40 CFR part 2, subpart B as it is “1) highlyguarded within the industry, 2) would not qualify as ‘emissions data’ subject to disclosure requirements, and 3) would harm the companies’ com petitive position if

disclosed.”

Response 9-a: EPA acknowledges the commenters’ concerns regarding reported information that they consider to be CB I. EPA carefully considered reporting and recordkeeping requirements and strived for a balance between the need for information that is important for analyzi ng and verifying reported emissions, and industry’s desire to protect certain information. At this time , EPA has determined emi ssion factors and gas usage and emissions by process type, sub-ty pe, or recipe are important pieces of information EPA is requiring to be reported u nder this rule because the information will provide a means for EPA to verify emi ssion estimates. The data elements EPA is requiring to be reported in the final rule wi ll permit annual verification of the emissions information and data reported by each facility EPA has determined that reporting this information is necessary for EPA to determine the emissions and ensure the consistency and accuracy of data collected under this rule. Please see response to comment 6-b on data reporting requirements. Please also see the preamble to the

Final MRR for additional information on EPA ’s verification approach (74 FR 56282).

Therefore EPA has not modified the data re porting requirements to exclude emissions and gas consumption by process sub-type.

Although it is not clear from the comment what less intr usive emission determination methods the commenter is referencing, EPA assumes the commenter may be referencing its suggested alternative methods for estimating emissions based on a facility-wide emission factor or factory modeling. However, because these methods have never been used in practice to EPA’s knowledge, it is unclear how theNovember 2010 92 implementation of such me thods would look and the dat a that would be used to

estimate emissions. It also is unclear what data EPA would need to be reported in order to verify emission estimates. Therefor e, EPA has no basis for conclusions about whether the suggested methods would be more or less intr usive than those proposed

or included in the final rule. EPA considered CEMS as a less intrusive emission estimation method in terms of data reporting, however as discussed in section 4.3,

information available at this time about the te chnical feasibility, a ccuracy, and costs of estimating emissions from electronics m anufacturing using CEMS is limited.

The final rule does not address whether data reported under subpart I will be treated as CBI. EPA is addressing CBI issues in a separate rulemaking. EPA published a proposed confidentiality determination on July 7, 2010 (75 FR 39094, July 2010) which

addressed the CBI status of ce rtain data elements. In t hat action, EPA proposed which specific data elements would be treated as CBI and which data elements must be available to the public under section 114 of the CAA. EPA has received several comments on the proposal and is in the process of consider ing these comments. Final determinations will be issued before any data is released, and the final determination

will include all of the data el ements under these subparts. For more information on the CBI rulemaking, please see, http://www.epa.gov/climatechange/ emissions/CBI.html#proposal.

Comment Summary 9-b: While some commenters (0110, 0123, and 0131) acknowledged EPA’s need to have the ability to verify emissions reports, many commenters raised issues with specific reporti ng elements of subpart I. Specifically, commenters argued that the majo rity of data required to be reported is not emissions data, and they questioned EPA’s need for some data elements. As well, commenters argued that providing some of this informati on to the public woul d cause substantial competitive harm to semiconductor manufac turing companies or cause a facility’s manufacturing operations to be inappropriately characterized. These elements, as well as who commented on them, are identified below.

1. substrate area production rates (0 089, 0099, 0110, 0123, 0131) (commenters also expressed that these values do not affect emissions results); 2. emission factors and process utilizati on rates broken out by processes or process categories and t he source (0089, 0095, 0131); 3. gas usage and emissions by process, process category, and/or process type (0099, 0100, 0110, 0123, 0131); 4. fraction of gas fed into each process type (0099, 0131); 5. apportioning factors (0131);

6. manufacturer and model number of each process tool (0099); 7. emissions from heat transfer fluid use (0131);

8. the method of emissions calculation used (0131); 9. description of individual processes or process categories used to estimate emissions (if process categories de fined by EPA are not used) (0131); 10. facility-wide gas-specif ic heel factors (0131); 11. fraction of gas fed into each pr ocess type with abatement systems (0131);November 2010 93 12. description of abatement devices, incl uding the number of devices of each manufacturer make and model, manufactu rer guaranteed DREs, and record of

DRE measurements made ov er its lifetime (0131); 13. all other information to be reported for abatement systems for which controlled

emissions are bei ng reported (0131); 14. inputs to the heat transfer fluid mass balance equation (0131); and 15. example calculations for fluorinated GHG, N 2 O, and heat transfer fluid emissions (0131).

Multiple commenters (0089, 0123, 0099, and 0110) suggested that some of this information could be kept on site and made avai lable for government inspection; one of the commenters (0089) asserts that this is consistent with the management for underlying emissions calculat ion data in other air qualit y and permitting programs. Two other commenters (0110 and 0123) suggested that, “Providing EPA with total emissions

on a CO 2 e basis and providing the remaining input s, such as methods of emissions calculations, emission factors used, et c., should provide sufficient data.” One commenter (0131) suggested that EPA adopt a proposed alternative approach for emissions reporting that would rely on less s ensitive information to be reported and that if EPA retains certain reporting elements they should explicitly acknowledge in the rule

what is not considered “emissions dat a” under EPA regulations and hence will not be subject to public disclosure.

Response 9-b: Of the elements identified by commenters as sensitive and listed above as items 1-15, all elements ot her than item 15, “example calculations for fluorinated GHG, N 2 O, and heat transfer fluid emissions” have been retained as reporting requirements in the final rule . Item 15 is not included in the final rule because EPA

determined that this information would be redundant with other in formation EPA is requiring facilities to report for emi ssion calculation verifications.

Although EPA is unsure exactly to which other air quality and permitting programs requirements the commenters ar e referring, in contrast to other regulatory programs, this rule focuses on establishing each facility’s annual GHG emissions in tons per year

, not on whether a facility's emissions are below a specified limit. For this reason, EPA is requiring reporting, rather than simply retention, of certain data in order to permit EPA

to conduct an annual verification of the emissi ons quantities reported by each facility.

Please see response to comment 9-a for details on the current CBI rulemaking and EPA’s need for required data r eporting elements. No data will be released publicly until

CBI determinations are made. For more information on the CBI rulemaking, please

see, http://www.epa.gov/climatechange/ emissions/CBI.html#proposal

.

Please see response to comment 2.3-a and 4. 5-a for more information about reporting of emissions on an absolute mass basis, as opposed to a CO 2 e basis.

Comment Summary 9-c: One commenter (0099) supported the current rulemaking efforts by EPA to define CBI in the context of the EPA Gr eenhouse Gas MandatoryNovember 2010 94 Reporting Program. The commenter asserted that neither the 2009 final rule nor the April 2010 proposed rule adequa tely protects CBI against public disclosure because

emissions data collected under CAA Sectio n 114 is generally not considered CBI. Another commenter (0131) str ongly urged EPA to move forward with this effort because “it is not legally appropriate for EPA to take the position that it ca n make ‘no promises’

at this time and to remain silent. The issue of trade secret protections goes to the heart of our business, and without any understanding whatsoever of EPA’s position on this issue, SIA does not have an ade quate opportunity for comment on this aspect of the Re-Proposal.”

Response 9-c : Please see response to comment 9-a for details on the current CBI rulemaking and EPA’s need for required dat a reporting elements. No data will be released publicly until CBI determinations are made. For more information on the CBI rulemaking, please see, http://www.epa.gov/climatechang e/emissions/CBI.html#proposal

.November 2010 95 

### 10. Uncertainty Analysis

Comment Summary 10-a: One commenter (0112) disagr eed with the premise that the Refined Method will reduce uncertainty associ ated with emission estimates by a factor of two without imposing undue economic burden on the semiconductor industry. The commenter indicated that this premise is not supported by t he analysis of the data provided by EPA in the re-proposal of the rule and associated documents. The

commenter constructed a Monte Carlo model and submitted results to EPA, concluding that the analysis by EPA contains severa l flaws. The commenter contended that their analysis suggests that the paucity of etch emissions data does not justify or support dividing the current Tier 2b etch category in to four separate categories. The commenter provided detailed descriptions of their model runs and concluded that using four etch categories does not reduce uncertainty by hal f. The commenter asserted that based on its analysis, the significant extra cost r equired to apportion gas use across four etch categories is not justified by the mi nimal improvement in certainty.

Response 10-a: EPA appreciates the work the co mmenter did to evaluate the uncertainty of the Refined Method. The analysis EPA conducted for the proposed rule

was based on the information available to EPA at the time. Using new information received after the proposed rule (presented in the NODA) and in the public comment period, EPA performed another uncertainty analysis evaluating the Refined Method and

four other emission estimation methods. From this analysis (see the Electronics Manufacture TSD, Appendix C) and in working to develop default factors for the Refined Method, EPA concluded that the emi ssion factor information available for the etching process type is not sufficient at this time to establish four etch sub-types as proposed for the Refined Method. Therefore the Refined Method is not a method required in the final rule. Additionally, the limited information available does not make it possible to draw any meaningful conclu sions about the certainty of various EPAdeveloped emission estimation methods and IPCC emissions estimation methods at this time. However, information gathered through the final rule will allow EPA to further

assess alternative emission estimation methods.

To address the gap for etch data noted above, under the final rule, the “largest” semiconductor manufacturing facilities must calculate their etch process emissions using recipe-specific emission factors. In future years, EPA may evaluate the recipespecific emission factors received through this final rule to determine whether a sufficiently robust data set exists to est ablish default emission factors for etching process sub-types. In the future, EPA may consider requiring the semiconductor facilities that will be using a default emission fa ctor for the etch process type under this final rule to estimate and report emissi ons using an approach based on multiple etch and chamber clean process sub-types simila r to the Refined Method EPA proposed in April 2010. At that time, EPA could reassess the certai nty of the Refined Method.

As a means to reduce burden to industry on t he whole, all other semiconductor facilities (i.e., those not classified as the “largest”) will utilize broad default emission factors for the etching process type, which were dev eloped by EPA using the data published in Table 5 of the report, “Draft Emission Factor s for Refined Semiconductor ManufacturingNovember 2010 96 Process Categories” (EPA-HQ-OAR-2009-0927-0073), to calculate emissions from a single etch process category, as o pposed to four etch categories.

For the other process types considered in this rule, EPA developed default factors for the three chamber cleaning process sub-types (i .e., in-situ plasma, remote plasma, and in-situ thermal) and broad fact ors for the wafer cleaning process type using data presented in the NODA. Please refer the Elec tronics Manufacture TSD, Appendix B for more information on the development of the default factors. Please see section 8 for

more discussion on the costs associated with the rule.

Comment Summary 10-b: One commenter (0099) assert ed that if the uncertainty assigned to emission factors for the Refined Method was reduced in comparison to the uncertainty assigned to Tier 2b emission fa ctors in the 2006 IPCC Guidelines, the uncertainty for emission factor s for the Tier 2b method shou ld be revised (improved) as

well. This is because Refined Method emi ssion factors are lar gely unchanged in comparison to the IPCC Ti er 2b emission factors.

Response 10-b: Please see response to comment 10-a for information on the data available to EPA at the time of the Apr il 2010 proposed rule. The information used to estimate emission factor uncertainties, as we ll as the emission factors themselves used for the analysis, was limited (see the Ma rch 22, 2010 Electronics Manufacture TSD, Appendix B for more details about the anal ysis). Based on the information, EPA had the uncertainty of each emission factor r epresenting a refined process category that

was calculated based on the standard deviation 42 of the emission factors measured for that process category in the 2006 IPCC dataset (see section B.2, page 25, of the March 22, 2010 Electronics Manufacture TSD). The ex ception was when a standard deviation couldn't be calculated because just one datum was available. In that case two runs were conducted. For one run, zero percent relative error was assumed around these factors and for the other run 10 percent re lative error was assumed per the ISMI

Guidelines. The difference in results betw een these two runs based on these different assumptions was inconsequential (see sect ion B.3, page 28, of the March 22, 2010 Electronics Manufacture TSD).

Please see response to comment 10-a fo r discussion on the emission estimation

methods for semiconductor facilities included in the final rule and on the updated uncertainty analysis. For detailed information on the updated uncertainty analysis please see Appendix C of the Electronics Manufacture TSD.

Comment Summary 10-c : One commenter (0131) present ed the ISMI’s supplemental survey regarding the Refined Method. The report, as attached by the commenter,

indicated that the Refined Method would in troduce even greater uncertainty than the
IPCC Tier 2 method. One r eason stated is that EPA’s uncertainty analysis fails to

42 In the uncertainty analysis, the 95% confidence in tervals presented in the 2006 IPCC Guidelines for the Tier 2b emission factors were divided by two so that they would be comparable to the uncertainties

calculated for the emission factors for the re fined process method, whic h are standard deviations.November 2010 97 account for the potential magnifying impact on uncertainty that can occur when the method establishes more categories for apportionment, due to the large amount of process recipes a facility would need to take into account during aggregated apportionment across many process tools.

The ISMI analysis identified the following pr oblems that made the commenter question the validity of the analysis: “1. The uncertain ties applied to the emissions factors used in the uncertainty analysis comparing the 9 category analysis to the Tier 2b categories analysis overstated the accuracy of the etch emissions factor s. Specifically, the use of 10 percent uncertainty for emissions fact ors with only a single data point and no specified uncertainty overstat es the certainty of the emi ssions factor value. 2. The gamma distribution truncated the distribution for emissions factors less than zero but an

infinite distribution tail for emissions factors great er than 1 resulted in 2 to 3 percent of the runs emitting more gas than was used in the process. This distribution reflects a major problem in the analysis. 3. The gamma distribution did not fit well with some of the data where the value of Uij was high. A bet a distribution provides a better fit to the available data and improves the Monte Carl o model output.” Th e commenter provided more information pertaini ng to the ISMI analysis.

Response 10-c: Although the Refined Method was not included in the final rule, the commenter’s concerns that apportioning gas consumption would introduce greater uncertainty to the emission estimates may al so apply to other meth ods that require the apportioning of gas consumption beyond the Ti er 2b method. However, the commenter does not provide quantitative evidence that such additional uncertainty would be introduced. In the uncertainty analysis that EPA performed for the April 2010 proposed rule, EPA explicitly stated that uncertain ties around gas distributions were not considered; given the available informati on (please see response to comment 10-a and 10-b), it was not feasible for EPA to estimate uncertainties that may be introduced by apportioning gas consumption. EPA believes that the methods for apportioning gas consumption provided in the rule minimize any uncertainty that may be introduced by apportioning gas to multiple process ty pes, sub-types, or recipes, because the apportioning factors must be developed based on quantifiabl e and documented metrics and facility-specific gas apportion ing models must be verified.

EPA took into consideration the commenter’s concerns about the uncertainty analysis run for the proposed rule. In light of these comments a nd new information that EPA received, EPA performed an updated uncertainty analysis that utilized emission factors and uncertainties based on information presented in the report, “Draft Emission Factors for Refined Semiconductor Manufacturing Process Categories” (EPA-HQ-OAR-2009- 0927-0073). The beta distribution, which E PA agrees has theoretical appeal because all physically impossible emission factors ( i.e. , those outside of the range of zero to one) would not be permitted in a Monte Carlo simulation, was used in the new analysis as well. However, two reasons attributed to the paucity of information—1) a small

number of emission factor estimates fo r each gas-process type other than the NF 3 - remote plasma clean process type, and 2) the unavailability of representative facilitylevel gas usage data. These data gaps precluded EPA from drawing robust conclusions about the uncertainty associated with alternative methods for estimatingNovember 2010 98 emissions. The small number of measured emission factors for each gas-process type precluded assessments of the valid ity of the theoretically attr active beta distribution. A potentially important and une xpected finding was that the IPCC Tier 2b method understated emissions compared to a Ti er 2b method developed using updated emissions factors obtained during EPA’s NODA . While EPA does not consider this

understatement of emissions es tablished (because it’s based on a single distribution of facility-level gas usage), it cannot ignore t he finding either (because the reason for this

bias results from the new emissions fact ors being larger than the older emissions

factors on which the IPCC Tier 2b default emission factors were developed). For more details on the uncertainty analysis, pleas e see Appendix C of the Electronics

Manufacture TSD.November 2010 99 

### 11. Other Subpart I Comments

Comment Summary 11-a: One commenter (0122) noted that over the last 15 years, SIA companies have worked to create a global program for PFC reduction for semiconductor manufacturing. Given this ef fort, the high complexi ty of semiconductor manufacturing, and the fact that the sector has relatively low emissions 43 (0.07 percent of national U.S. emissions), the proposed rule presented an excessive reporting and record keeping burden for facilities.

Another commenter (0110) noted that GHG emissions from the semiconductor industry were 0.55 MMTCE in 2008, comprising 0.07 per cent of the total U. S. inventory. The

commenter asserted that the amount of emissions subject to the rule by the industry is small, and that the industry has committed to reducing emissions to 10 percent below baseline by 2010.

Response 11-a: While the emissions from the electr onics sector repres ent a relatively

small share of total GHG emissions in t he U.S. and its industry Partners have reduced

emissions under the PFC Reduction/Climate Partnership for the Semiconductor Industry, EPA concluded it was appropriate to include this sector in the GHG Reporting Program. As discussed in section II.D of the Final MRR (74 FR 56270), EPA included source categories in the Program that woul d provide information necessary to evaluate facility-specific emissions that exceed t he selected emissions threshold across all sectors of the economy. Such data will info rm the assessment of potential policies and programs that could be implemented under the CAA. EPA consi dered a variety of factors in including the electronics manuf acturing sector in the Greenhouse Gas Reporting Program (GHGRP). First, the gases used in t he electronics manufacturing industry have extremely high GWPs and are persistent when released to the environment. There is a great diversity and significant volume of fluorinated GHGs used in electronics manufacturing and the sector ’s rapid growth indicates the potential for similar significant growth in future emi ssions. The collection of information through

this rule will allow EPA to i dentify and monitor the current and future trends in emissions of the potent GHGs used in the electroni cs manufacturing sector to inform policy and regulatory decisions. Please see response to comments in section 8 for information

about the burden associated with t he final rule. Please also see the preamble section D, Electronics Manufacturing (subpart I), section 3 (“Summary of Comments and Responses”), for the responses to comment s which discuss burden-reducing efforts.

Comment Summary 11-b: One commenter (0099) suppor ted reporting and reducing PFC and GHG emissions and has a stated goal of helping to ensure that the final rule is

based on the best available science without unnecessarily burdening manufacturers. Another commenter (0100) stated that a GHG inventory is an important first step toward reducing emissions but that emission in ventory methodologies should quantify

43 Modern fabs, such as advanced 300 mm fabs, have re latively low emissions because they use both insitu NF 3 chamber clean and POU abatement systems.November 2010 100 emissions reduction without diverting finite re sources from reducing actual emissions.

The commenter asserted t hat the Proposed Rule does not accomplish this.

Response 11-b: EPA appreciates the commenter’s stated goal of supporting a final

rule for the electronics sector that is based on the best ava ilable science without creating unnecessary burden. As already stated in this response to comment document, the EPA has made its best effort to balance the burden imposed on facilities with EPA’s goal of obtaining accu rate, facility-level data. T he methods in the final rule ensure that information is reported that hel ps further EPA’s understanding of the nature and magnitude of emissions from the electr onics industry and will help inform future policy and regulatory actions. Please see response to comment 8-f addressing burden. In gathering accurate facility-level uncont rolled and controlled emissions information EPA will have an established and accurate baseline on which to use to help inform future policy and regulatory decisions, potentially ones about emission reduction activities. Without an accurate baseline, the true magnitude and benefit of emission

reduction activities can not be assessed.

Comment Summary 11-c: One commenter (0110) s upported reporting necessary emission data to EPA. Based upon a review of the proposed rule and the results of the ISMI survey, the commenter stat ed that the rule is unnecessa rily complex and will result in unnecessary burden and costs to the indust ry. The commenter indicated that there are less burdensome monitoring and emission estimation alternatives that can be employed to achieve EPA’s goals, based upon the commenter’s experience with the EPA PFC Reduction/Climate Partnership for the Semiconductor Industry.

Response 11-c: There are emission estimation met hods available for facilities that manufacture semiconductors that may be less burdensome than the methods finalized in the rule. However, EPA has concluded that these methods, such as the IPCC Tier 2b method, are not sufficient for meeting the goals of this rule (for a discussion on why, please see response to comment 4.2-a and re sponse to comments in section 4.2.3). EPA is providing two methods in the final ru le by which semiconductor facilities are required to estimate and report emissions , based on the annual manufacturing capacity of a facility. Both of these methods move beyond the Tier 2b method in terms of their expected level of accuracy but do not impose as much bur den as is associated with a full Tier 3 method. The required methods, which are more granular than methods based on broad or no process types, help ensure that EPA is gathering accurate facility-wide information to inform future policy and regul atory decisions. Please also see response to comments 11-a and 11-b, as well as the response to comments on the cost

associated with the final rule in section 8.

Comment Summary 11-d: One commenter (0112) stated t hat the MRR must strike a balance between investment toward lowering emissions and expenditures on reporting

related infrastructure. The commenter asserted that the proposed rule goes well beyond what is necessary to develop the requi red emissions invent ory at the facility level. After the close of the public comment period the co mmenter provided twoNovember 2010 101 proposals for modeling PFC gas use and emissi ons to promote dialogue between the industry and EPA. The commenter encouraged EPA to continue conversations with industry after the close of the comment period.

Response 11-d: EPA appreciates the information on modeling fluorinated GHG gas usage the commenter provided. From t he examples the commenter provided, EPA gained further insight and understanding of plausible methods for apportioning gas consumption. In part based on the informa tion provided by the commenter, EPA has modified the gas apportioning methods in the final rule. EPA has determined that the requirements finalized in the rule are appropriate and effectively balance EPA’s objectives while minimizing burden to the indus try. As stated throughout this section and the comment response document, EPA sought to strike a balance between accurate facility-level reporting and burden on i ndustry to comply. EPA did not take into

account costs associated with emission reduct ion activities because that is beyond the scope of the rule. Please also see respons e to comments 4.1.2- and 8-d for more discussion on gas consumption apportionment m odeling methods finalized in the rule.

EPA thanks the commenter for the information prov ided to inform this rulemaking effort.

EPA looks forward to continued collaboratio n with electronics manufacturers as the GHG Reporting Program advances.

Comment Summary 11-e: One commenter (0122) cite d strong support for the comments submitted by the SIA on behalf of the U.S. semiconductor industry.

Response 11-e: Responses to SIA’s comments (c ommenter 0131) have been provided in all sections (1 though 11) of this document. Each of SIA’s comments, as with other commenters’ comments, has been segregated by topic area within each section in this

document.

Comment Summary 11-f: Two commenters (0099 and 0122) appreciated the changes in the re-proposed rule, which reduce many aspects of the overall reporting burden compared to the original proposal, and EPA’s decision to postpone finalizing requirements for the electronics manufactu ring sector. One commenter (0122) expressed ongoing concer n that many aspects of the proposed rule increase burden on the industry without corresponding benefits of either improved data accuracy or

reduced emissions.

Response 11-f: EPA appreciates the commenters’ suppor t of aspects of the April 2010 proposed rule that reduce over all reporting burden. In developing the final rule, EPA sought to achieve the goals of the rule and minimize burden imposed on industry. Details on steps taken to address burden are also provided in the various comment responses in the preamble section D, Elec tronics Manufacturing (subpart I), section 3 (“Summary of Response to Comments”).November 2010 102 EPA does not agree that the rule does not provide the benefits of improved data accuracy. The information gathered through this rule will provide EPA with accurate facility-level information across many sectors in the U.S.; the rule does not seek to or require facilities to reduce emissions. This rule addresses gathering accurate emissions, which may or may not eventually lead to potential future emission reduction policy decisions.

Comment Summary 11-g: One commenter (0131) apprec iated EPA’s responsiveness to their comments on the original propos ed rule. In particular, the commenter appreciated that the re -proposal would allow manufactu rers to calculate emissions instead of requiring individual tool meas urement or CEMS, neither of which the commenter believes is technically or economically feasible.

Response 11-g: EPA appreciates the commenter’s support for the revised proposal but disagrees with the commenter’s conc lusion that tool measurements are not technically feasible. The emission estimati on methods required in the final rule require

the use of default factors as well as direct measurement of recipe-specific emission factors in some cases; direct measurement fo r recipe-specific factors is feasible. While it may be feasible to use CEMS, the informati on available at this time about the use of this technology for the electronics manufacturi ng sector is limited. Further, information about the uncertainty of emission estimates us ing CEMS also is limited. In future years, given more information about the fe asibility of CEMS and the accuracy of estimating emissions from CEMS, EPA may cons ider providing provisions to allow for the use of CEMS. Please also see respons e to comment 4.3-a fo r more discussion of

CEMS.

Comment Summary 11-h: One commenter (0131) stated that EPA should allow more than the required three months to report prior calendar year data, because three months is not sufficient to collect, analyze, prepare, and certify data for submission. The

commenter noted that ot her programs allow longer time in tervals, such as six months for EPA’s Toxic Release Inventory and five months for California’s mandatory GHG reporting program.

Response 11-h: EPA disagrees with the commenter that thr ee months is not a sufficient timeframe to prepar e data and reports for submission to EPA. In the Final MRR, EPA decided that a thr ee month timeframe for compili ng, reviewing, certifying, and submitting annual GHG reports is suffic ient. For additional background on EPA’s

decision on the March submi ttal date for annual reports, please see the preamble to the October 2009 final rule ( 74 FR 56278-56279, October 2009).

Comment Summary 11-i: One commenter (0131) noted that the current proposed rule would appear to require gas -by-gas reporting of usage and emissions information by process category or sub-categor y on a mass basis without any CO 2 e conversion. The commenter expressed concern about this approach and saw no indication of whetherNovember 2010 103 EPA will make this information publicly availabl e (to the extent not claimed as CBI) or

will instead undertake to convert the data to CO 2 e. If EPA intends to undertake the conversion, the commenters questioned wh at methodology and GWP factors will be used and how the resulting data will be di splayed and explained to the public. The commenter proposed that CO 2 e conversion be performed by the reporting entity using

the latest IPCC GWPs.

Response 11-i: EPA is maintaining the requirement of gas-by-gas reporting of usage

and emissions information on a mass basis. Th is practice of re porting GHGs on a mass basis allows interested readers to easily calculate CO 2 e using current (or historical) GWP values, which have been ad justed over time to reflect improved scientific understanding. R eporting emissions by chemical mass eliminates one potential opportunity for calculat ion error and is very important to those investigating the concentration of pollutants in the atmo sphere and environment. The gas-specific reporting and analysis will also help identify chemicals for which GWP values need to be determined. Please see response to comment 2.3-a for more details on the GWPs

used in the MRR.

As EPA stated in the preambl e to the proposed rule to determine the confidentiality status of data required to be reported under the MRR (75 FR 39102), “pursuant to CAA section 114(c), EPA must make available to the public data submitted under Part 98, except for data (other than emission data) that are c onsidered confidential under CAA section 114(c). Accordingly, EPA intends to release Part 98 data after their submission

to EPA in accordance with EPA’s determinations of their confidentiality status in a final rule. Specifically, EPA intends to release Part 98 data that are determined in the final

rule to be emission data or not otherwise entitled to confidentia l treatment under CAA section 114(c) ( i.e., ‘‘non-CBI’’). EPA intends to make much of such data available to the public through an EPA Web site. Data el ements that we determine to be CBI under CAA section 114(c) would be pu blished on the Web site only if they can be aggregated in a manner that would pr otect the confidentiality of these data elements ( e.g., production data determined to be CBI that is aggregated by source category).”

Comment Summary 11-j: One commenter (0131) ur ged EPA to “recognize the significant initial challenges that will be posed by any new GHG reporting regime. Not only will companies need to create new comp liance systems, but EPA also likely will need to supplement any final rule creating, su ch as a regime with guidance, to address technical nuances or to clarify ambiguities. Consistent with EPA’s existing enforcement policies and practice, therefor e, SIA believes that enforcem ent should account for these initial challenges by using less aggressive me chanisms, such as the warning letter, and by encouraging industry to perform auditing and otherwise to take advantage of EPA’s Self-Disclosure Policy.”

Response 11-j: The enforcement provisions of the rule are critical to achieving EPA’s objective of collecting accurate GHG em issions data in a timely manner. EPA has discretion to pursue a variety of informa l and formal actions in order to achieve compliance.November 2010 104 EPA has implemented a compliance assistance e-mail and telephone hotline for answering questions and providing technical assistance. Compliance materials will be available for subpart I and are tailored to the needs of t he electronics manufacturing sector. These materials might include, for example, fact sheets, information sheets, plain English guides, frequently asked ques tion and answer documents, applicability tools, monitoring and recordkeeping checklis ts, and training on rule requirements and the electronic reporting system . Note that while EPA plans to issue compliance assistance materials, reporters should always consult the final rule to resolve any ambiguities or questions. For additional discussion of compliance and enforcement, including responses on EPA’s approach to enforcement, please s ee the preamble to the Final MRR, section VI. Compliance and En forcement (74 FR 56359, October 2009).November 2010 105 

### 12. Relevant Comments from th e April 2009 Proposed Rule on Electronics Manufacturing

12.1 Calculating GHG Emissions: Em ission Estimation Methods for

Semiconductor Facilities

Comment Summary 12.1-a: One commenter (0498) asse rted that while “large semiconductor facilities” (those that have an annual manufacturing capacity of greater than 10,500 m 2 of substrate) are subject to t he most stringent requirements under subpart I, they do not have inherently highe r emissions of fluorinated GHGs. The

commenter stated that the second generation of 200 mm f abs and 300 mm fabs have significantly lowered their emissions in co mparison to older fabs by incorporating

remote NF 3 chamber cleaning and POU abatement systems. The commenter (0498),

as well as another commenter (0682), stated that “the dist inction in the Proposed Rule between ‘large’ facilities and other facilitie s – appears based on the premise that all larger facilities will have newer technology – but this premise does not square with the current manufacturing realities. Within the semiconductor i ndustry, a large facility may rely on older technology. So me facilities may contain mu ltiple fabrication operations, with a mix of technology gener ations.” The two comm enters (0498 and 0682) further

stated that the distin ction is contradictory to emi ssion reduction incentives developed under the Voluntary EPA Partners hip, which does not distinguish facilities by capacities in setting emission reduction goals. Theref ore these commenters, as well as another commenter (1137), asserted that there should be no di stinction between large and

other semiconductor facilities and that the ru le should apply to all facilities that emit more than 25,000 metric tons of CO 2 e per year.

One commenter (0978) asserted that the use of square meters of silicon to establish the reporting threshold is inappropriate. The commenter stat ed that silicon wafer throughput is considered CBI and does not provide a meaningful assessment of GHG

emissions— it is a metric that varies wid ely depending on the process and the facility.

The commenter recommended that t hat the rule should apply to all facilities that emit more than 25,000 metric tons of CO 2 e per year using pre-abatement PFC emissions as estimated by IPCC Tier 2 or 3 method. T he commenter argued that this would provide an effective, easy metric at which to set a reporting threshold.

Response 12.1-a: In the final rule, for semiconductor facilities that manufacture wafers measuring 300 mm and less in diameter, EPA is requiring the use of one of two of the following methods for calculating and reporting emissions, depending on the facility’s manufacturing capacity: (1) A method for fac ilities that have an annual manufacturing capacity that is less than or equal to 10,500 m 2 of substrate (the Tier 2c method), and (2) a method for those that have an annual m anufacturing capacity greater than 10,500

m 2 of substrate (the Tier 2d method).

While EPA acknowledges qualitative reports on second generation 200 mm wafer facilities adopting NF 3 remote plasma cleans and POU abatement systems as presented in comments, EPA is unaware of published studies t hat quantitativelyNovember 2010 106 document the market penet ration of either NF 3 remote plasma source or point of use fluorinated GHG abatement systems in thos e facilities. EPA could not rely on generalizations about how industry practices, such as the use of NF 3 RPS and abatement systems, affect emissions that ar e not substantiated by consistent published data and supporting information from commenter s. Therefore EPA selected a capacitybased emission estimation met hod distinction of 10,500 m 2 of substrate for the largest

facilities because facilities above this thres hold are expected to account for nearly twothirds of potential emissions, while accountin g for less than 20 percent of all facilities expected to report under subpart I. This di stinction was part of EPA’s initial April 2009 proposed rule (74 FR 16448, October 2009). By setting this distinction, EPA established an easily calculated metric 44 which can be used to determine which

facilities must use the Tier 2c or Tier 2d methods in a consistent manner. EPA has concluded that the methods finalized in this rule effectively balance EPA’s objectives with an appropriate level of burden to industry.

EPA does not agree that finalizing a distincti on between reporting requirements for the larger and relatively smaller semiconductor m anufacturing facilities is contradictory to emission reduction incentives developed und er the EPA’s PFC Reduction / Climate Partnership for the Semiconduc tor Industry because the Partnership and this rule have different purposes and goals. The purpose of this rule is to collect data for use in developing future GHG policies and programs. In contrast, t he Partnership (a nonregulatory program) is designed to support the industry’s voluntary e fforts to reduce its high GWP GHG emissions. In the final rule, EPA is requiring reporting methods for semiconductor manufacturing facilities based on the facility’s manufacturing capacity (representative of potential emissions), to effectively balance EPA’s objectives in addressing relatively large uncertainties associated with abatement performance with an appropriate level of burden to the industry as a whole.

Please see the preamble section D, Electr onics Manufacturing (subpart I), section 3, (“Summary of Response to Comments”) for additional response to comments on the methodologies for semiconductor manufacturing facilities in the final rule and also on steps EPA has taken to reduce burden.

With respect to the commenter that asserted the use of silicon to determine threshold applicability is inappropriate, in the final ru le, the threshold calculation to determine whether a facility is required to report under subpart I is emissions-based (as proposed in the April 2010 rule). The emissions-based threshold is different from the capacitybased threshold that was presented in the April 2009 proposed rule. EPA is retaining a capacity-based threshold for semiconductor facilities to determine which methodology they are required to follow to calculate and report their emissions (please see the first paragraph in this response for more informati on). EPA is not requiring the use of wafer throughput in that calculation; rather, the threshold applicability calculation uses the facility’s annual manufacturing capacity.

44 In the final rule EPA has clearly specified the equations and information a facility must use to determine their annual manufacturing capacity.November 2010 107 In the final rule, all electr onics manufacturing facilities that emit more than 25,000 metric tons per year of CO 2 e are required to report under subpart I. Please see the preamble section D, Electronics Manufacturing (subpart I), section 1, for a summary of the reporting threshold for electronics manuf acture, and the preamble to the Final MRR (74 FR 56272, October 2009) for further di scussion on EPA’s selection of a 25,000

MtCO 2 e per year reporting threshold. Please al so see response to comments on CBI in

section 9.

Comment Summary 12.1-b: One commenter (0437) asserted that it is unclear, for the Tier 3 method, whether every process, every recipe, or ev ery platform would have to be tested. The commenter reques ted clarification regarding how to address similar tools and processes used across multiple facili ties. The commenter questioned whether testing would be required to be company-specific , facility-specific, or tool-specific. The commenter also requested clar ification on the required test ing frequency for the Tier 3 method and the trigger for testing. In a similar sentiment, another commenter (0498) also questioned what would constitute a sepa rate process that would necessitate the development of a specific set of Tier 3 emission factors. The commenter asserted that it is neither technically appropriate nor wo rkable from a regulatory standpoint to develop emission factors for every individual recipe used. Another commenter (0759) suggested if the same manufac turing processes were used in multiple company fabs, emission factors developed in one fab shoul d be allowed to be applied for the same processes run in another fab. The commenter stated that bec ause of the highly precise nature of the industry, the same manufacturing processes will be performed identically across different facilities; as such, the method suggested would accurately estimate

emissions.

Response 12.1-b: In the final rule, EPA is clarifying that for methods which require the use of emission factors developed from direct measurements (i.e., both the Tier 2d and Tier 3 methods), factors must be develo ped for each recipe used at the facility. However, EPA recognizes that a facility may employ potentially hundreds of individual recipes. To this end, as a means to reduc e burden for facilities th at are required or elect to do recipe-specific measurements, EPA is introducing the term “similar,” with respect to recipes, to refer to recipes that are composed of the same set of chemicals

and have the same flow stabilization ti mes and where the documented differences, considered separately, in r eactor pressure, individual gas flow rates, and applied radio frequency (RF) power are less than or equal to plus or minus 10 percent. For purposes of comparing and documenting recipes that ar e similar, facilities may use either the best known method provided by an equipment manufacturer or the process of record,

for which emission factors for either have been measured (see the Electronics Manufacturing TSD (EPA-HQ-OAR -2009-0927) for supporting information). Once a facility develops a set of recipe-specific emi ssion factors for an individual recipe, it may apply those emission factors to “similar recipes.” This prov ision allows a facility to make fewer measurements to develop the emission factors required for Tier 2d and Tier 3, thereby reducing burden in com parison to a more stringent approach which would require measurements for each and every individual recipe used at a facility. For

additional information about the Tier 2d and 3 methods, please see the preambleNovember 2010 108 section D, Electronics Manufacturing (subpart I), section 1 (“Sum mary of the Final Rule”).

As another means to reduce burden, EPA is cl arifying that in a given reporting year, a facility must develop new recipe-specific emi ssion factors only for recipes which are not similar to any recipe used in a previous reporting year. Further, EPA is allowing facilities to use recipe-specific utilizati on and by-product formation rates measured by a third party, provided the meas ured recipes are similar recipes to those used at the facility. 45 For more information on similar recipes please see the Electronics Manufacture TSD. For additional respons es to comment on burden, please see the preamble section D, Electronics Manufacturi ng (subpart I), section 3 (“Summary of Comments and Responses.”)

Comment Summary 12.1-c: Three commenters (0437, 0498, and 0978), who supported the use of the Tier 2b method, stated that EPA’s und erstanding of the availability of Tier 3 data from tool suppliers, and the current use of the Tier 3 method throughout industry, is incorrect. The comment ers also asserted that the Tier 3 method would be excessively burdensome fo r facilities to implement.

One of the commenters (0498) asserted that t he cost to implement the Tier 3 method at a large fab would range from $0.43 million to $2.7 million, and would require anywhere

from 12 to 76 weeks of te sting, depending on whether every process platform 46 or whether every individual recipe had to be te sted. The cost to the EPA-estimated 29 “large facilities” was estimated to be $13 mil lion to $77 million total, with an estimated 360 to 2,200 weeks of testing required. The co mmenter (0498) also asserted that given the limited number of testing serv ice providers, it is unclear how Tier 3 factors could be developed for all large semiconductor facilities. 47 Another comment er (0978) stated

that neither of its facilitie s currently have the capacity to track and record data in support of a Tier 3 method. The commenter estimated that $5 million in initial investments would be required to implement the Tier 3 me thod, including modifications and upgrade to equipment and software, and $1. 5 million per year would be required in operating costs. The comm enter (0978) was concerned that there would not be sufficient time to install required hardware and software systems to implement the Tier 3 method in order to comply with the rule; the commenter stated t hat to install the required hardware and software may take several years and may introduce risks into manufacturing processes.

45 In the final rule, recipe-specific utilization and by -product formation rates are required to be measured using the 2006 ISMI Guidelines. EPA is allowing re cipe-specific utilization a nd by-product formation rates measured using the 2001 ISMI Guidelines provi ded they were measured prior to January 1, 2007. Documentation for the measurements is required.

46 The commenter defined a process platform as specific tool models using a specific PFC for either CVD

chamber clean or etch.

47 In the April 2009 proposed rule, the largest semiconductor facilities (with annual manufacturing capacities of greater than 10,500 m 2 ) were required to use the Tier 3 method to estimate all etch and

clean emissions.November 2010 109 Response 12.1-c: EPA has concluded that an emission estimation approach based on

the IPCC Tier 3 method would result in t he most accurate data. However, EPA is mindful of the burden that would be imposed by requiring all covered facilities to apply a Tier 3 method for all process emissions. To this end, EPA is not finalizing an approach that requires semiconductor manu facturing facilities to calc ulate and report using a Tier 3 method for all production proc esses that use fluorinated GHGs . In the final rule, only the largest semiconductor manufacturing fac ilities are required to calculate and report emissions for the plasma etching proce ss type using directly measured emission factors (Tier 2d method).

Note, in the final rule, EPA is finalizing an approach that requires all semiconductor manufacturing facilities that fabricate devices on wafers measuring larger than 300 mm in diameter to calculate and report all produc tion processes that use fluorinated GHGs using a Tier 3 method. As EPA stat ed in the April 2010 proposed rule, the commissioning process for new tools is an ideal opportunity for emission factor development and/or verification. Further, EPA stated, by including this requirement only for the wafers larger than 300 mm, “we anticipate a reduction in burden because emission factors (i.e., gas utilization and by-product format ion rates) can be developed over a number of years as semiconductor manufacturers begin to transition to 450 mm tools and develop the estimating and reporti ng infrastructure. The commissioning process for new tools is an ideal opportunity for emission factor development and/or verification.” To this end, EPA does not believe that requiring facilities that fabricate devices on wafers measuring larger than 300 mm in diameter to calculate and report emissions using a Tier 3 method is over ly burdensome. For additional information

about the methods finalized for semiconductor manufacturing facilities that fabricate devices on wafers measuring larger than 300 mm, please see the preamble section D, Electronics Manufacturing (subpa rt I), section 1 (“Summary of the Final Rule”), and section 4.2.2.2 more discussion of the requir ed Tier 3 method for facilities fabricating devices on wafer measuring greater than 300 mm.

With respect to the comments on costs, EPA has updated its costs estimates to reflect costs associated with the requirements finaliz ed in rule. EPA has concluded that its final cost estimates appropriately account fo r the compliance burden under this rule. For details on how EPA developed its final costs for this rule, please see Sections 4 & 5 of the Economic Impact Analysis (EIA) (a vailable in the docket, EPA-HQ-OAR-2009- 0927).

For details on steps EPA has taken to r educe the burden, please see the preamble section D, Electronics Manufacturing (subpart I), section 3, which contains the response

to comments on emission estimation met hods for facilities that manufacture semiconductors and respons e to comments on burden.

For those facilities that are required to calculate and report emissions for the plasma etching process type using recipe-specific fa ctors, EPA is mindful of the time it may take facilities that are required to perform direct emission measurements to comply with the rule. To this end, EPA is allowing all facilities to use “best available monitoring methods” (BAMM) for the first six months of data collection (through June 30, 2011) forNovember 2010 110 any parameter for which it is not reasonably feasible to acquire, install, or operate a required piece of monitoring equi pment in a facility or to pr ocure measurement services from necessary providers. EPA is also a llowing facilities to apply for the extended use of BAMM for the remainder of the first year of data collection (through December 31, 2011). For example, if a facility is unabl e to procure the necessary measurement services by December 31, 2011 to measure a ll of its plasma etching emissions using recipe-specific emission fa ctors, and EPA approves it s BAMM request, it may use

default etch emission factors to calculat e and report its 2011 emissions. Under this scenario, the facility must then recalculate and report its 2011 emissions with its 2012 report. Please see the preamble section D, Electronics Manufac turing (subpart I), section 1, for more details on the BAMM provisions. Please also see response to comment 4.2.1.2-b for responses to comment re lated to the availabi lity of Tier 3 data.

Comment Summary 12.1-d: Two commenters (0498 and 0682) asserted that facilities that possess Tier 3 measur ement data should use the dat a to estimate emissions, provided the data are representative of fac ility processes and reflective of accepted analytical practices, such as the 2006 ISMI Guidelines (a lthough both commenters argued that it is not appropriate to mandate the Guidelines). T he commenters asserted that if a facility does not possess Tier 3 data, the Tier 2b method should be used.

One commenter (0437) asserted that the published Tier 2 default emission factors are objective and the use of Tier 2 factors for a ll covered facilities w ould increase regulatory certainty and reduce the risk of non-compliance. The commenter further stated that it is

not clear that the Tier 3 me thod would necessarily be more accurate than the Tier 2b method. Another commenter (0978) also stat ed that the additional costs of the Tier 3 method, relative to the Tier 2b method, were not justified because of the limited increase in accuracy offer ed by the Tier 3 method.

In a similar sentiment, another commenter (0498) stat ed that the Tier 3 method offers only an incremental improvement in accura cy over the IPCC Tier 2 methods. The commenter supported this statement by pr esenting results from an analysis which compared emission estimates from multiple fabs resulting from the use of the 2006 IPCC Tier 2a, Tier 2b, and Tier 3 emi ssions estimation methods and the related

uncertainties. The commenter asserted that due to the inherent unc ertainties of GWP values used in estimating emissions with the IPCC methods, and the incremental improvements the Tier 3 method offers may not be justified by the associated costs.

One commenter (0498) present ed the results of an industr y survey that showed only one company using the Tier 3 method and all other companies who responded to the survey using the Tier 2a, 2b, or a combination of those methods.

One commenter (0759), who relies for the most part on its own developed emission factors, compared its own resu lts to the results that w ould have been obtained if the commenter had used the Tier 2b method; th e commenter found that on average the Tier 2b method overestimated emission by ~ 10 percent. This commenter asserted that if accuracy beyond the Tier 2b method is requi red, emissions testing should be phasedNovember 2010 111 in over time due to the large amount of te sts that would be needed in order to comply.

The commenter asserted that this phase-in approach is c onsistent with the approach used by EPA and state and local agencies for other regulated air pollutants, such as VOCs. The commenter argued that in many ca ses it is considered acceptable to use average AP-42 emission factors rather than emission factors measured directly on-site.

Response 12.1-d: The 2006 IPCC Guidelines state that the Tier 3 method is estimated

to result in the least uncertain estima tes amongst the methods presented by IPCC (please see response to comment 4.2.2.1-a for more discussion on the accuracy of the Tier 3 method). EPA agrees with the af orementioned statement and continues to

maintain that the Tier 3 met hod will result in the most cert ain emission estimations. For this reason EPA does not want to prohibit the use of the Tier 3 method if a facility elects to do so; therefore EPA is permitting any faci lity covered under subpart I to use the Tier

3 method. 48 EPA is also requiring some facilities covered under subpart I (semiconductor facilities that manufacture wafers measuring 300 mm and less and that have an annual manufacturing capac ity of greater than 10,500 m 2 , and facilities that manufacture wafers measuring greater t han 300 mm) to use the use recipe-specific emission factors (i.e., a parti al or full Tier 3 method, re spectively). Please see the preamble section D, Electronics Manufacturi ng (subpart I), section 3, (“Summary of Response to Comments”) for additional resp onse to comments on the methodologies for semiconductor manufacturing facilities in the final rule and section 4.2.2.2 for discussion on the required used of the Tier 3 method for facilities manufacturing wafers measuring greater than 300 mm. For more discussion on why EPA did not finalize the Tier 2b method as proposed for semiconductor facilities please see response to
comments 4.2.-a, 4.2. 1.2-c and 4.2.3-a.

For facilities required or that elect to use re cipe-specific emission factors (i.e., a full or partial the Tier 3 method), EPA has provided means to ease compliance with the rule

and reduce the burden associated with emissi ons testing. For example, EPA is requiring only direct measurement for the etch ing process type for some facilities. In addition, EPA is requiring only the largest fa cilities (manufacturing wafers measuring 300 mm or less) to estimate and report thei r etch emissions using recipe-specific emission factors. Lastly, EPA is allowi ng any factors that were developed for one individual recipe to be applied to similar reci pes (as defined in the final rule). EPA is also permitting the use of BAMM for any param eter, such as recipe-specific emission factors, that can not reas onably be measured within the first six months of data collection. Please see response to comment 12.1-c for more in formation on BAMM.

48 To ensure consistent methods of calculating and reporting emissions, EPA is prohibiting a facility from creating and using a hybrid method – a facility must us e the appropriate methods required in the rule, or use recipe-specific emission factors to estimate all production processes that use fluorinated GHGs. This restriction will enable EPA to analyze emissions and tr ends using a consistent set of data. The only exception is where a facility is required to use a me thod using default emission factors but no defaults are provided in Tables I-3, I-4, I-5, I-6, or I-7 for a particular fluorinated GHG and process type or sub-type

combination. Where default emissi on factors are not provided, a fac ility must either use utilization and by-product formation rates of 0 or, in that particu lar instance, use directly measured recipe-specific emission factors measured using the 2006 ISMI Guidelines with limited exceptions.November 2010 112 EPA disagrees with the commenter’s (0498) argument that due to the inherent

uncertainties of GWP values the incremental improvements the Tier 3 method offers may not be justified by the associated costs fo r two reasons. First, EPA is not requiring emissions to be estimated and reported on a CO 2 e basis; emissions must be reported on an absolute mass basis. Second, EPA believes that any uncertainties in GWP values would affect any method us ed to estimate emissions in CO 2 e, not only the Tier 3 method. For response to comments about the GWPs used in this rule please see response to comment 2.3-a.

The commenter (0498) did not provide EPA with the underlying data or assumptions used to further assess the uncertainty analysi s presented in the comment. In regards to another commenter’s (0759) analysis, which resulted in t he conclusion that on average

the Tier 2b method overestimated emissi on by ~10 percent, information and data supporting how the commenter arrived at c onclusion was also not provided to EPA. Based on an uncertainty analysis performed by EPA for this final rule, which compared

various emission estimation methods for one hypothetical fab, EPA found that the IPCC Tier 2b method understates emissions, which is contradictory to what the commenter (0759) concluded. The uncertainty analysis run by EPA also led to the conclusion that more emissions data, particula rly data for the etching process type, is needed to allow for robust and meaningful results comparing various methods. Please see the Electronics Manufacturing TSD (available in the docket, EPA-HQ-OAR-2009-0927) for more information on the uncertainty analysis. The limited information available does not make it possible to draw upon any statistically significant results about the certainty of various EPA-developed emission estimati on methods (e.g., the Refined Method, and the Tier 2c and Tier 2d methods) versus IPCC emission estimation methods at this time. However, information gathered thr ough the final rule will allow EPA to further

assess alternative emission estimation methods.

Also please see response to comment 4.1. 2-c for more discussion on the relationship between this rule and air quality regulations.

12.2 Monitoring and QA/QC Require ments: Use of the 2006 ISMI

Guidelines

Comment Summary 12.2-a: One commenter (0437) asse rted that there may have been some misunderstanding in regards to EPA requiring the use of the ISMI

Guidelines for emissions characteri zation. The commenter questioned EPA’s requirement to use the ISMI Guideline for em issions testing in the rule, because it was developed for tool manufacture rs as an "aspirational" guide and was "meant to provide considerable latitude" in characterizing eq uipment emissions rat her than serve as "a complete emission test method...[or]...a complete equipment purchase standard". The commenter further argued that the IS MI Guideline is not a SEMI standard 49 nor widely

49 Per the commenter: “SEMI is the trade association for the tool manufacturing industry. According to SEMI, SEMI standards are voluntary technical agree ments between suppliers and customers, aimed at improving product quality and reliability at a reasonable price and steady supply. SEMI standards purportedly cover every aspect of semiconductor ma nufacturing: Equipment Automation (Hardware and Software), Facilities, Gases, Ma terials, Microlithog raphy, Packaging, Proc ess Chemicals, andNovember 2010 113 used as such (to the extent of the commenter’s understandi ng). Two other commenters (0498 and 0682), who supported the use of acceptable analytical practices such as the

2006 ISMI Guidelines in devel oping Tier 3 emission factors, stated that it is not appropriate to mandate the use of the Guidelines.

Response 12.2-a: EPA has concluded that requiring the use of the Guidelines is appropriate and beneficial for purposes of this rule. Therefore in the final rule EPA is requiring that recipe-specific emission factors be measured using the 2006 ISMI Guidelines, with limited exceptions. 50 By requiring that em ission factors be measured using the 2001 or 2006 ISMI Guidelines, EPA is relying on the only established industry practices for quantitatively characterizing em issions under conditions of actual wafer processing rather than dev eloping an alternative. 51 EPA has not proposed nor does it

view the ISMI Guideline as an emissions compliance testing me thod or procurement standard, as one commenter asserted. Please also see section 5.1 on the required use

of the 2006 ISMI Guidelines.

EPA does not agree that the ISMI Guidelines are “aspirational.” The 2006 version of Guidelines explicitly state t hat: “The semiconductor industry has a responsibility to its employees and the community to minimi ze the environmental impact of its manufacturing processes and operations. To fu lfill this responsibility, environmental performance goals have been set for its processe s and operations. It is essential that equipment suppliers help the semiconduc tor industry achieve these goals. Consequently, equipment supplie rs are expected to design their tools to minimize the consumption of chemicals, production of wa ste emissions, and usage of utilities such as energy and water. This document provi des guidance to suppliers of process equipment and abatement devices on how to characterize the environmental performance of their tools and devices. The characterization must include the quantification of air emissions, liquid effl uents, and solid wast e generated by the process equipment (tool) or point -of-use (POU) abatement device.”

The methods provided in the Guidelines sp ecifically require that for all emissions measurements, among other things, those making the measurements (1) adhere to the use of two protocols that describe FTIR and QMS for the ex press purpose of measuring fluorinated GHG emissions, (2) a dopt specific methods of calib ration that stipulates a minimum number of calibration points, a calibration performance metric (slope of calibration curve), and performance standard <=5 percent of that sl ope, (3) adhere to specific methods for calculating utilization efficiency of process gases, (4) achieve a fluorine-volume closure standard of >90 per cent unless a plausib le explanation with supporting data is provided, and (5) documen t results of measur ements in a standard reporting template. These and other practices pr ovided in the Guidelines will result in

robust emission factors that are developed in a consist ent manner; a feature which

Traceability. Guidelines are also developed to cover safety related issues. In addition, standards are published for Flat Panel Displays. The publication catal ogue provides a listing of the available standards and guidelines. www.semLorg/ en/Standards/P_000787.”

50 See footnote 21.

51 According to the authors listed to the antecedent guidelines, the Guidelines were not only developed among industry experts. ISMI sought and secured the ex pertise of NIST, a federal technology agency, in developing its guidelines for characterizing emissions.November 2010 114 allows EPA to compare emissions across the industry as well as track trends in industry practices.November 2010 115 

### 13. Other Changes

General changes: Sections of the proposed regulat ory text were reorganized and editorial changes were made to improve clar ity and readability in the final regulatory

text.

General changes: The proposed regulatory text often referred to production, production process, process type, and process category. For clarity, in the final regulatory text the term “process category” was revised to be “p rocess sub-type.” The

new suite of terms results in a more underst andable and consistent flow of process tiers - production processes, process types, and process sub-types.

To §98.90(a): This paragraph was revised to clarif y that it is the manufacturing processes (i.e., those defined in §98.90(a)(1) th rough (5)) that trigger the applicability of subpart I rather than a specif ic product that is manufactu red (e.g., semiconductors).

To §98.90(a): The proposed paragraph §98.90 (a)(4 ), which described the following production process, “Each electronics manufac turing production process in which some fluorinated compounds can be transformed in the plasma processes into different fluorinated compounds, whic h are then exhausted, unless abated, into the atmosphere,” was removed from the regulatory text bec ause it was redundant with other production process descriptions and intr oduced a level of uncertainty regarding

what is covered under the electroni cs manufacturing source category.

To §98.90(a)(5): This paragraph was revised to clar ify that production processes for heat transfer fluids include cleaning substrat e surfaces and other par ts. In the April 2010 proposed rule, proposed in §98.98, the definition of hea t transfer fluids included cleaning substrate surfaces and other par ts. The definition was as follows:

Heat transfer fluids are fluorinated GHGs used for temperature control, device testing, and soldering in certain types of electronic manufacturing. Heat transfer

fluids used in the electronics se ctor include perfl uoropolyethers, perfluoroalkanes, perfluoroethers, tertiary perfluoroamines, and perfluorocyclic

ethers. Heat transfer flui ds commonly used in electronics manufacturing include

those sold under the trade names ‘‘Galden ®’’ and ‘‘FluorinertTM.’’ Electronics manufacturers may also use these same fluorinated chemicals to clean substrate surfaces and other parts.

EPA has retained this definition of HTFs in the final rule, 52 and has aligned the description of process that uses HFTs in t he source category with the HTF definition to include processes in which HTFs are used to clean substrate surfaces and other parts.

To §98.91: The calculations in this section of s ubpart I were restructured for clarity in calculating emissions for threshold applicability purposes.

52 In the final rule EPA removed reference to the trade na mes of HTFs in the definition. This edit did not change the meaning of and HTF in the final rule.November 2010 116 To §98.92(b): This paragraph was added to clarify t hat consumption of fluorinated

GHGs and N 2 O should be reported for all fluorinated GHG and N 2 O using processes at a facility (see proposed §98.96(f), 75 FR 18702, Ap ril 2010). EPA is clarifying this point to ensure that the Agency will receive comp rehensive information on use and emissions of GHGs from electronics manufacturing fac ilities so that EPA may stay fully informed of new and emerging uses of these pot ent GHGs. The trend in electronics manufacturing has been to continuously ex plore and commercialize innovative new uses for fluorine-based chemistries and processes. The complete reporting of all

fluorinated GHG and N 2 O consumption and uses will advise future policy decisions and allow EPA to adjust its emissi on calculation methods to a ccurately reflect current industry practice.

To §98.93: This section was restructured for clarit y and flow. One example of a change made is that process types and process sub-ty pes, previously defined in this section in the proposed regulatory text, were moved to §98.98, “Definitions.”

To §98.93: Paragraph §98.93(a) wa s expanded and paragraph §98. 93(a)(6) was added in this section to provide a facility that is using an emission estimation method based on default emission factors, methods to estimate emissions in instances where that facility uses a fluorinated GHG(s) for a particular process type or sub-type for which default

emission factors are not available in Tables I- 3, I-4, I-5, I-6, or I-7. Where default emission factors are not available, a facilit y has the option to either use utilization and by-product formation rates of zero or, in that particular instance, use directly-measured recipe-specific emission factors meas ured using the 2006 ISMI Guidelines,

International SEMATECH #06124825 A-ENG, with limited exceptions. 53 EPA

understands that there are instances where a facility is engaging in a particular production process and a default emission factor is not provided in the Tables. For this reason, EPA added specific provisions for a facility to follow.

To §98.93(a)(3): This paragraph was added to allow any electronics manufacturing facility reporting under subpart I, regardless of the products it manufactures, to estimate and report emissions using recipe-specific em ission factors (i.e. a method based on the IPCC Tier 3 method.). EPA made this change so that any electronics manufacturing facility may report using a methodology that results in the most accurate emission

estimates.

To §98.93, Equation I-10: In the proposed rule, EPA requi red the aggregate amount of

N 2 O emitted at a facility to be reported. However, EPA notes that this was not

consistent with how fluorinated GHG emissions were required to be reported; they were required to be reported by process type, not in aggregate amounts. Therefore, for consistency the noted equat ion, to calculate N 2 O emissions (proposed Eq. I-9), was revised to require N 2 O emissions from each CVD and other N 2 O-using manufacturing process to be calculated and repor ted separately. This is di fferent from the equation in the proposed regulatory text, which required all N 2 O emissions to be summed and then reported as a total quant ity. In requiring N 2 O emissions to be reported for each CVD

53 See footnote 21.November 2010 117 and other processes EPA can gain information on N 2 O consumption practices in the industry to help inform future regulatory and policy decisions.

To §98.93, Equation I-11: The definition of the input variable D i in this equation, to calculate gas consumption (proposed Equation I-9), was corrected to account for all disbursements of input gases, not just dis bursements of input ga ses in exceptional

circumstances.

To §98.93, Equation I-12: This equation, to calculate disbursements of an input gas (proposed Equation I-11), was modified to acc ount for an instance w here a facility could have multiple facility-wide gas-specific heel factors for one input gas. This instance would occur where a facility may use multip le container sizes and types of one input

gas.

To §98.93, Equation I-13: This equation was added to clarif y the method facilities must use to calculate the amount of gas appor tioned to recipes, process sub-types and process types (or CVD and other N 2 O-using manufacturing processes), using apportioning factors developed with facilit y-specific gas consumption apportioning

models.

To §98.94(b)(4): This paragraph was revised to clar ify that for mass-based trigger points for change out, exceptional circumstan ces must be determined based on the net weight of gas in the container, excluding the tare weight of the container.

To §98.96 and §98.97: The reporting and recordkeeping requirements were revised in some instances to align with new methods pr ovided in subpart I, for reporting clarity,

and to ensure that EPA would collect nec essary information for emissions data

verification.

To §98.98: For clarity in complying with the subpart I requirements and to make the regulatory language simpler to follow, the fo llowing definitions were added to the final regulatory text: actual gas consumption, c hamber cleaning (including definitions for the three chamber cleaning sub-types, in-situ pl asma, remote plasma, and in-situ thermal), class, dominant gas, modeled gas consumption, plasma etching, process sub-type, process type, redundant abatement systems, repeatable, wafer cleaning, and wafer starts. In addition, the def inition of uptime was modified to account for the changes made for calculating uptime in the final regulatory text.

To Table I-8: This table was created for consistency. Default emission factors for N 2 O that were previously presented in proposed paragraphs §98.93(c)(1)(ii) and (c)(2)(ii) were moved out of the regul atory text and are now present ed in Table I-8, Default

Emission Factors for N 2 O, consistent with the other default emission factors.November 2010 118 

### Appendix A: List of Commenters Sorted by Submission Number

Submission No. Commenter Organization

EPA-HQ-OAR-2008-0508 -0437 Jay Hawkins Micron Technology Inc.

EPA-HQ-OAR-2008-0508 -0498 Thomas Diamond Semicondu ctor Industry Association

EPA-HQ-OAR-2008-0508 -0682 Laurie A. Lehmberg Texa s Instrument Incorporated

EPA-HQ-OAR-2008-0 508-0759 Tim Higgs Intel Corporation

EPA-HQ-OAR-2008-0508 -0978 Jay M. Dietrich IBM

EPA-HQ-OAR-2008-0 508-1137 Robert N, Fielding Freescale Semiconductor

EPA-HQ-OAR-2009-0 927-0074 Joe Van Go mpel MIDAC Corp.

EPA-HQ-OAR-2009-0 927-0089 Tim Higgs Intel Corporation

EPA-HQ-OAR-2009-0 927-0093 Sanjay Baliga SEMI

EPA-HQ-OAR-2009-0927 -0095 Nadia Wetzler Applied Materials, Inc.

EPA-HQ-OAR-2009-0927 -0099 Laurie A. Lehmberg Texa s Instrument Incorporated

EPA-HQ-OAR-2009-0927 -0100 John D. Holmes Freescale Semiconductor

EPA-HQ-OAR-2009-0 927-0107 Mary K. Smickenbec ker Matheson Tri-Gas Inc.

EPA-HQ-OAR-2009-0927 -0108 Alan P. Abbott Microchip Technology

EPA-HQ-OAR-2009-0927 -0110 Dale Eldridge Micron Technology Inc.

EPA-HQ-OAR-2009-0927 -0112 Jay M. Dietrich IBM

EPA-HQ-OAR-2009-0 927-0122 Reed M. Content Gl obal Foundries U.S., Inc.

EPA-HQ-OAR-2009-0927 -0123 Bob Cartensen Tran sform Manufacturing, LLC

EPA-HQ-OAR-2009 -0927-0124 Mark Vickery Texas Commission on Environmental Quality

EPA-HQ-OAR-2009-0 927-0128 Pamela Campos En vironmental Defense Fund

EPA-HQ-OAR-2009-0927 -0131 Thomas Diamond Semicondu ctor Industry Association
Trans-DC-02 Thomas Diamond Semiconductor Industry Association

Trans-DC-03 Peter Zalzal Environmental Defense FundNovember 2010 119 

### Appendix B: Additional Commen ts on the EPA DRE Protocol

(Submitted by SIA – EPA-HQ-OAR-2009-0927-0131)

The comments included below are only t hose that have not been previously submitted in the DRE Protocol peer review process. Comments received previously, and the EPA responses are available in the docket EPA-HQ-OAR2009-0927

.

Comment B-1 (General Comment): Why is it acceptable to use a tracer approach to determine tool effluent flow but not acceptable for abatement system

effluent flow?

Agree with the considerati on for a properly mixed samp le which the tool pump provides at the tool effluent as well as the concern when dealing with non-ideal ducts (ones which may not contain lami nar flow) as often at the abatement system effluents. The missing piece is the demonstration that t he injected tracer is homogeneously mixed with the abatem ent system effluent flow. Propose to add a stratification test to the protocol in support of t he post-abatement flow

tracer method. This stra tification test can be easily performed by stepping the FTIR sample probe across the abatement sy stem effluent duct at depths of 25%, 50% and 75% (or more if desired) while me asuring the tracer gas concentrations by FTIR. Should the concentrations be consistent at each depth into the abatement system effluent duct the tr acer/effluent can be considered homogenously mixed and the flow determi nation can continue with the probe centered in the duct. Furthermore, the gases incorporated for tracers are also the same PFCs commonly monitored at these fa cilities, albeit absent of the particular process for flow determinations. Therefor e, if the FTIR data is acceptable for

concentration measurements used for DRE determinations it should be acceptable for flow determination by the process described above. Previous results have displayed very repeatable resu lts at various tracer injection rates. Two other experiments comparing FTI R and QMS tracer studies for flow determination are planned for the next fe w months. One will be at a laboratory using a 4” mixing duct and a second in late June at a semiconductor facility.

Another issue of concern is the stabilit y of the QMS measur ements during these tests. Previous testing results demonstr ated very tight deviations using FTIR concentration results over multiple tracer release flow rates. With the inherent drift, ambient pressure inlet and calibrati on issues associated with the QMS (and alluded to in the protocol Section 2.2.4) it is a concern that the QMS will not be able to produce data quality equal to the FTIR approach.

Response B-1: EPA sought comment on the use of the DRE Protocol in the proposed rule for Electronics Manufacturi ng (75 FR 78652, Ap ril 2010),,but not

on the actual content of the Protocol itself.

EPA began considering the need for a DRE measurement Protocol for the semiconductor industry in 2006 as par t of the PFC Reduction/ClimateNovember 2010 120 Partnership with the Semiconductor Industry. The Protocol development process

included three DRE measurements studies at three different Partner facilities, from May 2007 through December 2008. 54 After the first two measurement studies and subsequent reports, EPA devel oped and shared the first draft of the

DRE Protocol in November 2007 with natio nal and international peer reviewers, including the ISMI GHG Working Group, Japan El ectronics and Information Technology Industries Association (JEI TA), Industrial Technology Research Institute (ITRI), and other industry consulta nts. After receiving and responding to

all comments on the first draft of t he Protocol, EPA engaged in a third DRE measurement study, which in formed preparation of second draft of the Protocol.

EPA then shared the second dra ft of the Protocol with peers in June 2009, and subsequently responded to all of the comme nts received on the second draft of the DRE Protocol. During these peer review processes, the original

measurement methods and data treatment methods, together with the testing and reporting methodology (which inco rporated a performance metric and performance standard) were demonstrated to be suitable and practical across three US fabs (older and newer). EPA received no peer comments that its methodologies were inappropriate or not su pported by its data or current industry knowledge. The Protocol was then fina lized, taking into account all of the published, in-fab DRE measurement informati on, in March 2010. This was just prior to the publication of the proposed subpart I (published in April 2010), for which development began in respons e to the FY2008 Consolidated Appropriations Act (H.R. 2764; Public Law 110–161).

EPA sponsored and developed the DRE Protocol in cooperation with its industry

Partners. The Protocol build s on and augments industry emission characterization practices and guidance (e.g., ISMI 2001 and 2006 Guidelines) by focusing on proper DRE measurement (e.g., ensuring dilution is properly accounted for) whether in voluntary or r egulatory circumstances. The publication

of the DRE Protocol fills a void for te chnical guidance on pr oper measurement of abatement system DREs.

EPA viewed the publication of the DRE Pr otocol just prior to the April 2010 proposal of subpart I as beneficial for the industry because in seeing the measurement guidance that would be incor porated by reference in the final rule, EPA believed interested parties—espec ially non-Partners and the public—could

comment on the use of the Protocol in the rule. EPA did not receive public comments on the rule arguing that requiri ng the use of the DRE Protocol would

54 For more information about the three st udies, please see the following reports: Developing a Reliable Fluorinated Greenhouse Gas (F-GHG) Destruction or Removal Efficiency (DRE)

Measurement Method for Electronics Manufac turing: A Cooperative Evaluation with IBM (EPA 430-R-10-004); Developing a Reliable Fluorinated Greenhouse Gas (F-GHG) Destruction or Removal Efficiency (DRE) Measurement Method for Electronics Manufacturing: A Cooperative Evaluation with NEC Electronics, Inc. (EPA 430-R-10-005); and Developing a Reliable Fluorinated Greenhouse Gas (F-GHG) Destruction or Removal Efficiency (DRE) Measurement

Method for Electronics Manufacturing: A Cooperative Evaluation with Qimonda (EPA 430-R-08- 017).November 2010 121 lead to DRE measurement practices that would not be robust or results that

would be inaccurate.

The method the commenter is proposing, which EPA interprets as the same method included in Appendix B of the 2009 ISMI Guidelines and as what has been referred to as the JEITA method, had not been subject to an in-fab testing environment, nor had it been robustly co mpared to methods for measuring dilution using a QMS at the time the DRE Protocol wa s published. While there is

theoretical reason to believe the me thod may work and should be capable of achieving the performance standard set in the Protocol, based on a call with peer

reviewers of the DRE Protocol on Februar y 25, 2010, it was ev ident that at the time of publication of the DRE Protoc ol additional research and documented infab testing was needed to dem onstrate the validity of th e suggested method. For these reasons, EPA did not include the “JEI TA” method in Version 1 of the DRE Protocol. However EPA appreciates that testing of the suggested method is currently being planned or performed by industry, and would be open for discussion and review of any test results using the method. EPA welcomes more information about new qualified measurem ent methodologies that the Agency may consider incorporating into future ve rsions of the Protocol. Please also see response to comment 5.2.4.1-a for more information about the use of an FTIR in place of a QMS for measuring dilu tion with tracers t hat are inert.

Comment B-2 (Section 1.3. Protocol Scope): Typo in Section 1.3, paragraph 3, 4th sentence should have the "the" removed between standard and relative.

Response B-2: EPA thanks the commenter for their input, and will correct the typo in future versions of the Protocol . EPA notes that this typo does not change the meaning of the sentence.

Comment B-3 (Section 2.1.1, Descr iption of Experimental System): In Figure

1 consideration needs to be taken when lo w purge-flow pumps are employed. If the sample exhaust is not returned to the tool effluent do wnstream of the extraction location it will impact the DRE as the inlet mass loading will be lower than normal operation. This is only applic able when the extracted flow is not negligible compared to t he tool effluent flow.

Response B-3: EPA interprets this comment to apply when measuring DRE while simultaneously measuring proce ss gas effluent (PGE) and abatement gas effluent and when PGE sampling flow compri ses an affecting portion of the total PGE flow. Under this condition, the charge into the abatement system is understated because in Fig. 1 the PGE sampli ng flow is returned to the facility’s waste stream post abatement (i n the abatement system effluent).November 2010 122 Experienced metrologists should be awar e of such a circumstance in part because of their experience. Because PGE concentrations are relatively high (1,000 ppm or higher), FTIR sampling cells are of small volume, meaning PGE sampling/extraction flows can be low. EPA's experience in the DRE measurement program is that PGE sampli ng/extraction flows are typically <0.5 LPM. PGE flows, however, are typically 30 - 40 LPM. So, even at 0.5 LPM extraction flow, less than 2 percent of t he flow is not returned to the abatement system, which is inconsequential for DRE measurement. Even for the unusually low PGE flow of 10 LPM, the charge to the abatement system would be less than 5 percent for extraction flows <0.5 LPM.

Nonetheless, EPA agrees that metrologi sts should be aware of this rare circumstance, which is why the Protoc ol recommends that only experienced metrologists--experienced in FTIR and QMS practices in electronic manufacturing facilities-- be permitted to carry out DRE measurements.

Comment B-4 (Section 2.2.1, Method 1): In section 2.2.1 (DRE determination with plasma off) a specified flow of 120% of the process flow is stipulated to ensure the abatement system is tested under conditions that may occur during processing. The PFC concentrations will be much greater than normal as is (not being disassociated by a plasma).

Response B-4: During the EPA DRE measurement program, EPA used a flow of 120% of the process flow and found no issues in actual application. The use of 120% of the process flow for Method 1 is a suggested practice. Given the flexibility of the Protocol, a facility coul d depart from this practice provided there is plausible reason, and that this reason is documented.

Comment B-5 (Section 2.2.2, Method 2): Typo in 2.2.2, 2nd paragraph, 3rd sentence “...all operating chambers that are”

Response B-5: EPA thanks the commenter for their input, and will correct the typo in future versions of the Protocol . EPA notes that this typo does not change the meaning of the sentence.

Comment B-6 (Section 2.2. 3, Equipment Needed): The suggestion of using a PFC that passes through the abatement system with DRE<5% to determine abatement system effluent flow forms a ci rcular argument. Per the protocol, one must demonstrate that the abatement syst em DRE for the compound is <5% by
QMS and tracer studies before us ing the PFC tracer approach.

Response B-6: The Protocol provides two pl ausible methods for demonstrating

a DRE of less than 5% for tracer co mpounds other than noble gases (e.g., CF 4 orNovember 2010 123 SF 6 ): (1) the manufacturer of the POU abatement system provides results, based on the methods of this Protocol, that t he DRE of the chemical tracer is <5% under the operating conditions being tested at the f ab using the QMS and the noble gas tracer methodology or (2) in-fab tests showing <5% destruction of the

chemical tracer on a POU abatement system (based on t he QMS and noble gas tracer methodology of this Protocol fo r one abatement system in the fab) may be used on abatement system in the facility of the same make and model installed and operated in the same manner as the a batement system tested. Based on the methods suggested, for one abatement system a facility or POU manufacturer could use a QMS and the noble gas tracer methodology to demonstrate that for that particular abatement system the DRE of the fl uorinated GHG tracer gas being used (e.g., CF 4 or SF 6 ) is less than 5%. This demonstration would then hold true for any abatement system in the same class as the tested system, and hence an approach using an fluorinated GHG tracer would be permitted for any system in that class. Therefore EPA does not agree that a circular argument is

created as the DRE Protocol does not specify that the demonstration must be completed for every individual abatement system for which a facility or POU

manufacturer wants to use suitabl e fluorinated GHG tracers.

Comment B-7 (Section 2.2.4, FTIR and QMS Protocols): Current version

states scan times should be on the order of 3 seconds. Not all FTIRs have the capacity to scan at such a high rate. One of the systems we have collects 1 scan/1.7 seconds plus you have factor in the processing time. Also short scans

will increase MDLs at the abatement system effluents.

Response B-7: The scan times identified in t he Protocol are suggested scan times based on EPA experience. As such, a facility may use an FTIR that scans

at a different rate and still adhere to t he DRE Protocol provided all data is adjusted appropriately. The data treatm ent methods specified in the DRE

Protocol correct for various scan rates using a method of weighted variances.

Comment B-8 (Section 2.2. 5, Calibration Curve): Current version states the necessity to bracket (within the FTIR re ference set for the particular compound) the observed concentration ranges and onl y considers absorption features between 0.1 and 1.0 absorbance units (a.u.). Although it is good practice, it is not always practical or necessary. Since mo st PFCs have broad absorption features they are linear over large concentration r anges. It is a fair assumption that the linear behavior can be extrapolated to c oncentrations ~50% greater than the largest reference should the compound ex hibit linear behavior. In the last sentence of 2 paragraph of 2. 2.5 it alludes to this by stating that all nonlinear

curves must bracket the observed concent ration range. Alternating cells at the

tool effluent FTIR can elim inate the ability to obser ve byproducts. It is also cumbersome to switch between plasma off/on experiments to ensure that

concentrations are bracketed or the 0.1-1.0 a.u. range is conserved.November 2010 124 Response B-8: The practices regarding the use of FTIRs specified in the DRE Protocol are suggested good practices. As such, a facility may deviate from the suggested practices if they can not be follo wed, provided the facility has a valid and documented reason for why, and the performance standard set by the DRE

Protocol is maintained.

Comment B-9 (Section 2.2. 5, Calibration Curve): The suggestion to only quantify over FTIR absorbance features between 0.1-1.0 absorbance units (a.u.) is rather restricting (Sections 2.2.4, 2.2.5 & 2.2.7). There are often numerous

usable features outside this 0.1-1.0 range.

The lower bound of this range would be be tter represented by a factor offset based on the FTIR system noise, say absorbanc e features at a minimum of 1.5 times the system noise are acceptable fo r use. Common system noise levels are

on the order of 10-3 and most of the time much better. Using 0.1 a.u. as the lower bound is requiring that absorbance f eatures be 100 times (or more) your system noise to be usable. An illustrati on of this is depicted below in the FTIR

reference for SO 2 (For illustration see EPA-HQ-OAR-2009-0927-0131). This SO 2 feature displayed is the band most oft en quantified. The peak absorbance is less than 0.1 a.u. (0.04 a.u.), but remains well above the system noise. The FTIR cell path length of 10.5m is common for semi-conductor sampling, therefore normalizing the SO 2 concentration to fall withi n the 0.1-1.0 range yields approximately 136 ppm r equired to quantify SO 2 using this absorbance feature.

Similarly, there is a lot of usable information to be gathered from absorbance features greater than 1.0 a. u. I feel a better repres entation of the upper bound

would be features that ar e not opaque (totally absorbing) and quantify at no more 50% of the concentration of the largest reference in the particular compounds’ set. Of course this only applies to li near absorbing compounds which the PFCs are. A skilled spectroscopist meteorologis t) would know when this is appropriate. Furthermore, when determining the tool effluent flow, this is often the case as it is necessary to run the process recipe (per t he protocol Section 2. 2.1) with the tool plasma off. This is the case when det ermining tool utilization as well.

Granted SO 2 is not a GHG but it is a by-product of SF 6 processes. The protocol also does state that it is acceptable to go outside of this range so long as the reference set bracket it which is easy to do on the lower bound by adding a zero (or noise spectrum) to your reference set. However, l ooking forward, if this protocol is to be applied for other com pounds this restrictive range may provoke an issue where good data could be non- acceptable.

Response B-9: The scope of the DRE Protocol is specifically focused on measuring fluorinated GHG abatement. Pl ease see response to comment B-8 about suggested FTIR practi ces in the Protocol.November 2010 125 Comment B-10 (Section 2.2.6, Fl ow and Dilution Measurement): Same as 2.2.3 comment - The suggestion of us ing a PFC that passes through the abatement system with DRE<5% to deter mine abatement system effluent flow forms a circular argument. Per the pr otocol, one must dem onstrate that the abatement system DRE for the compound is <5% by QMS and tracer studies before using the PF C tracer approach.

Response B-10: Please see response to comm ent B-6 about using a fluorinated GHG tracer approach.