## NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR

POLLUTANTS FOR POLYVINYL CHLORIDE AND

COPOLYMERS PRODUCTION

SUMMARY OF PUBLIC COMMENTS AND RESPONSES

U.S. Environmental Protection Agency Office of Air Quality Planning and Standards Sector Policies and Programs Division Research Triangle Park, North Carolina 27711

February 2012ii The primary contact regarding questions or comments on this document is:

Jodi Howard (919) 541

- 4607 U.S. Environmental Protection Agency OAQPS/Sect or Policies and Programs Division Refining and Chemicals Group (E143

- 0 1 ) Research Triangle Park, North Carolina 27711

Email: howard.jodi @epa.goviii TABLE OF CONTENTS

Section Page No.

1.0 INTRODUCTION

................................ ................................ ................................ ........... 1

- 1
2.0 LIST OF COMMENTERS

................................ ................................ .............................. 2

- 1
3. 0 AFFIRMATIVE DEFENSE

................................ ................................ ............................ 3

- 1
4.0 APPLICABILITY

................................ ................................ ................................ ............ 4

- 8 5.0 AREA SOURCES

................................ ................................ ................................ .......... 5

- 11
6.0 BEYOND

- THE

- FLOOR ANALYSIS

................................ ................................ .......... 6

- 12
7.0 EQUIPMENT LEAKS

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

- 15
7.1 Compliance and Monitoring

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

- 15
7.2 Emission Limits, Operating Limits, and Work Practice Standards

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

- 17
8.0 HEAT EXCHANGE SYSTEMS

................................ ................................ ................... 8

- 18 9.0 OTHER EMISSION SOURCES

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

- 20
10.0 PROCESS VENTS

................................ ................................ ................................ ...... 10

- 22
10.1 Compliance and Monitoring

................................ ................................ ............ 10

- 22
10.1.1 General Support of Process Vent Floors and Compliance

................... 10

- 22 10.1.2 General Concerns with Process Vent Floors and Compliance

............ 10

- 23 10.1.3 Closed Vent Systems and Control Device Bypass

.............................. 10

- 24 10.1.4 CEMS/CPMS

................................ ................................ ....................... 10

- 31 HCl CEMS

................................ ................................ ................................ ....... 10

- 34 VCM CEMS

................................ ................................ ................................ ..... 10

- 36 CPMS

– Selection of Monitored Parameters

................................ ................... 10

- 41 CPMS

- Miscellaneous

................................ ................................ .................... 10

- 43 10.1.5 Stack Testing

................................ ................................ ........................ 10

- 49 10.2 Emission Limits, Operating Limits, and Work Practice Standards

................. 10

- 56
10.3 MACT Floor

................................ ................................ ................................ .... 10

- 58
11.0 RESIN

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

- 59
12.0 STORAGE VESSELS

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

- 60
13.0 WASTEWATER

................................ ................................ ................................ .......... 13

- 68
13.1 Compliance and Monitoring

................................ ................................ ............ 13

- 68
13.1.1 Relaxed testing for wastewater streams

................................ ............... 13

- 68 13.1.2 Point of determination (POD) / Intermittent wastewater

..................... 13

- 71 13.1.3 Rule Clarifications Requested

................................ .............................. 13

- 71 13.1.4 Samplin g/Analysis Methods

................................ ................................ 13

- 73 13.1.5 General

................................ ................................ ................................ . 13

- 75 13.2 MACT Floor

................................ ................................ ................................ .... 13

- 77iv

14.0 COMPLIANCE DATES

................................ ................................ .............................. 14

- 79 15.0 DEFINITIONS AND TERMINOLOGY

................................ ................................ ..... 15

- 80
16.0 EMISSION LIMITS, OPERATING LIMITS, AND WORK PRACTICE STANDARDS 16

- 89
17.0 GENERAL SUPPORT OF OTHER COMMENTERS

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

- 90
18.0 IMPACTS

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

- 92
18.1 General

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

- 92
18.2 Air

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

- 93
18.3 Cost

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

- 95
18.4 Non

- Air Qualit y Health, Environmental, and Energy

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

- 96
19.0 MACT FLOOR, GENERAL

................................ ................................ ....................... 1 9

- 99 20.0 REGULATED POLLUTANTS

................................ ................................ ................. 20

- 101
21.0 REGULATORY OVERLAP

................................ ................................ ..................... 21

- 101
22.0 RESIN MORPHOLOGY

................................ ................................ ........................... 22

- 103
23.0 RULE

................................ ................................ ................................ ......................... 23

- 104
23.1 General

................................ ................................ ................................ ........... 23

- 104
23.2 Format

................................ ................................ ................................ ............ 23

- 104
24.0 STARTUP, SHUTDOWN, AND MALFUNCTIONS

................................ .............. 24

- 105 25.0 STATUTORY AUTHORITY

................................ ................................ ................... 25

- 112
26.0 SUBCATEGORIES

................................ ................................ ................................ ... 26

- 113
27.0 VARIABILITY

................................ ................................ ................................ .......... 27

- 113
28.0 CROSS REFERENCES AND CITATIONS

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

- 117 29.0 DOCKET

................................ ................................ ................................ ................... 29

- 118
30.0 INFORMATION GATHERING

................................ ................................ ............... 30

- 120
31.0 STATUTORY AND EXECUTIV E ORDERS

................................ .......................... 31

- 120
32.0 NOTIFICATIONS, RECORDKEEPING, AND REPORTS

................................ ..... 32

- 122
33.0 MISCELLANEOUS

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

- 1281

- 1



### 1.0 INTRODUCTION

On May 20 , 2011 , EPA proposed National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production

. This document contains summaries of the public comments that EPA received on the proposed standards

. In this
document and in the preamble t o the final rule , EPA responds to the public comments

. Copies of all comments submitted are available at the EPA docket Center Public Reading Room

. Comment letters and transcripts of the public hearings are also available electronically through http://www.regulations.gov by searching Docket ID EPA

- HQ

- OAR

- 2002

- 0037

.2

- 1



### 2.0 LIST OF COMMENTERS

The EPA received 40 comment letters on the proposed National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chlori de and Copolymers Production after the rule proposal

. Comments from two public hearing s held on June 7, 2011 and June 9, 2011 are also
included in this document

. All comment letters and the two public hearing transcripts are contained in Docket EPA

- HQ

- OAR

- 2002

- 0037

. The commenter, affiliation and item number in
Docket EPA

- HQ

- OAR

- 2002

- 0037 are listed in Table 2

- 1

. The public hearing commenter, affiliation, and item number are listed in Table 2

- 2. A list of acronyms and units of measure used
in this document appears after the list of commenters.

Table 2

- 1. Public Comments Received After the Proposed Rule for National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers

Production , Proposed Rule Docket EPA

- HQ

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- 2002

- 0 037

Co mmenter Identification Code Commenter and Affiliation EPA

- HQ

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- 2002

- 0037

- 0118 Jean

- Cyril Walker, Keller and Heckman LLP EPA

- HQ

- OAR

- 2002

- 0037

- 0120 G. Vinson Hellwig, Co

- Chair, Michigan and Robert H. Colby, Co

- Chair, Chattanooga, Tennessee, Air Toxics C ommittee, National Association of Clean Air Agencies (NACAA) EPA

- HQ

- OAR

- 2002

- 0037

- 0121 John S. Lyons, Director, Energy and Environment Cabinet, Department for Environmental Protection, Kentucky Division for Air Quality EPA

- HQ

- OAR

- 2002

- 0037

- 0122 Russell G . Grizzle, Chief Operating Officer, Mannington Mills, Inc. EPA

- HQ

- OAR

- 2002

- 0037

- 0124 Rich Walker, President and CEO, American Architectural Manufacturers Association (AAMA) EPA

- HQ

- OAR

- 2002

- 0037

- 0125 Bruce Hollands, Uni

- Bell PVC Pipe Association EPA

- HQ

- O AR

- 2002

- 0037

- 0126 Bill Gulledge, Senior Director, Chemical Products & Technology Division, American Chemistry Council (ACC) Vinyl Chloride Health Committee (VCHC) EPA

- HQ

- OAR

- 2002

- 0037

- 0127 Michael Cudahy, Codes and Training Specialist, Plastic Pipe and Fi ttings Association (PPFA) EPA

- HQ

- OAR

- 2002

- 0037

- 0 131 Paul A. Yost, Vice President Energy and Resources Policy
, National Association of Manufacturers (NAM) EP A

- HQ

- OAR

- 2002

- 0037

- 0133 Hal Bozarth, Executive Director , Chemistry Council of New Jersey (CCN) EP A

- HQ

- OAR

- 2002

- 0037

- 0134 Kenneth G. Akins, Director Corporate Environmental , Georgia Gulf Corporation (GGC) EPA

- HQ

- OAR

- 2002

- 0037

- 0135 Marie R. Martinko, Director, Industry Affairs, Environment & Health, Society of the Plastics Industry, Inc. (SPI) EPA

- HQ

- OAR

- 2002

- 0037

- 0136 Kevin D. Ott, Coordinator, Flexible Vinyl Alliance EPA

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- OAR

- 2002

- 0037

- 0137 David Friedman, Senior Director, Regulatory Affairs, National Petrochemical & Refiners Association (NPRA)2

- 2

Co mmenter Identification Code Commenter and Affiliation EPA

- HQ

- OAR

- 2002

- 0037

- 0138 William L. Kovacs, Senior vice President, Environment, Technology & Regulatory Affairs, U.S. Chamber of Commerce EPA

- HQ

- OAR

- 2002

- 0037

- 0139 Mark D. Pettegrew, Global Director, Environmental Health & Safety (EH&S)

- Product Stewardship, PolyOne Corporation EPA

- HQ

- OAR

- 2002

- 0037

- 0140 Judith R. Morgan, Chair, Environmental Laboratory Advisory Board (ELAB) EPA

- HQ

- OAR

- 2002

- 0037

- 0141 Lorraine Krupa Gershman, Director, American Chemistry Council (ACC) EPA

- HQ

- OAR

- 2002

- 0037

- 0142 Bob Elam, The Dow Chemical Company EPA

- HQ

- OAR

- 2002

- 0037

- 0143 Tokesha M. Collins, Kean Miller LLP on behalf of Louisiana Chemical Association (LCA) EPA

- HQ

- OAR

- 2002

- 0037

- 0144 Jim Hodges, Site Manager, Shintech EPA

- HQ

- OAR

- 2002

- 0037

- 0145 Christopher G. Mundschenk, Executive Director, Wallcoverings Association (WA) E PA

- HQ

- OAR

- 2002

- 0037

- 0146 Peter L. de la Cruz and Jean

- Cyril Walker, Keller and Heckman LLP on behalf of Vinyl Institute, Inc. EPA

- HQ

- OAR

- 2002

- 0037

- 0147 Judith D. Nordgren, Managing Director, Chlorine Chemistry Division, American Chemistry Council (ACC) E PA

- HQ

- OAR

- 2002

- 0037

- 0148 Stephen P. Risotto, Senior Director, Phthalate Esters Panel, American Chemistry Council (ACC) EPA

- HQ

- OAR

- 2002

- 0037

- 0149 Lauren P. Alterman, Vice President, Environment, Health and Safety, Saint

- Gobain Corporation EPA

- HQ

- OAR

- 2002

- 0037

- 0150 James Pew, Earthjustice EPA

- HQ

- OAR

- 2002

- 0037

- 0151 Mary P. Bachynsky, Manager, Corporate Air Program, Formosa Plastics Corporation, U.S.A. EPA

- HQ

- OAR

- 2002

- 0037

- 0152 Lloyd R. Cress, Jr., Dinsmore & Shohl LLP on behalf of Kentucky Association of M anufacturers (KAM) EPA

- HQ

- OAR

- 2002

- 0037

- 0153 Barry Christensen, Manager Air Quality, Occidental Chemical Company (OCC) EPA

- HQ

- OAR

- 2002

- 0037

- 0154 Mark D. Pettegrew, Global Director, Environmental Health & Safety (EH&S)

- Product Stewardship, PolyOne Corpo ration EPA

- HQ

- OAR

- 2002

- 0037

- 0155 Dean Thompson, President, Resilient Floor Covering Institute EPA

- HQ

- OAR

- 2002

- 0037

- 0156 Christina T. Wisdom, Vice President & General Counsel, Texas Chemical Council EPA

- HQ

- OAR

- 2002

- 0037

- 0157 Chris Farley, Environmental E ngineer, Wacker Chemical Corporation EPA

- HQ

- OAR

- 2002

- 0037

- 0158 Bertram M. Lederer, Executive Vice President , Teknor Apex Company EPA

- HQ

- OAR

- 2002

- 0037

- 0159 Therese M. Cirone, Vice President of Health, Environment, Safety and Security , The Chlorine Institu te (CI) EPA

- HQ

- OAR

- 2002

- 0037

- 0160 Kevin Bloomer, Senior Environmental Engineer, Westlake Chemical Corporation EPA

- HQ

- OAR

- 2002

- 0037

- 0161 Jerry Y. Huntley, President and CEO, Vinyl Siding Institute (VSI) EPA

- HQ

- OAR

- 2002

- 0037

- 0162 Randall W. Marvel, Vice P resident

- Supply Chain/Strategic Initiatives, RJF International Corporation2

- 3

Co mmenter Identification Code Commenter and Affiliation EPA

- HQ

- OAR

- 2002

- 0037

- 01 63 (Duplicate of 0126) Bill Gulledge, Senior Director, Chemical Products & Technology Division, American Chemistry Council (ACC) Vinyl Chloride Health Commi ttee (VCHC) EPA

- HQ

- OAR

- 2002

- 0037

- 01 64 Mark A. Biel, Executive Dire ctor, Chemical Industry Council of Illinois (CICI)

Table 2

- 2. Public Comments Received During the June 7, 2011 and June 9, 2011 Public Hearings on the National Emission Standards for Ha zardous Air Pollutants for Polyvinyl

Chloride and Copolymers Production , Proposed Rule

Commenter Identification Code Commenter and Affiliation PH

- BR

- 0001 Otis Sistrunk, PolyOne Corporation PH

- BR

- 0002 Richard Krock, Vinyl Institute PH

- BR

- 0003 Mary Bac hynsky, Formosa Plastics Corporation PH

- BR

- 0004 Christine Bennett, Mossville Environmental Action Now (MEAN) PH

- BR

- 0005 Delma Bennett, Mossville Environmental Action Now (MEAN) PH

- BR

- 0006 C. Dean Thompson, Resilient Floor Covering Institute PH

- BR

- 0007 Allen Blakey, Vinyl Institute PH

- BR

- 0008 Beverly S S miley, Solutions Through Science PH

- BR

- 0009 Henry Graham, Jr., Louisiana Chemical Association PH

- BR

- 0010 Wilma Subra, Louisiana Environmental Action Network (LEAN) and the Lower Mississippi River Keep er PH

- BR

- 0011 Monique Hardin, Advocates for Environmental Human Rights and Mossville Environmental Action Now (MEAN) PH

- H

- 0001 Otis Sistrunk, PolyOne Corporation PH

- H

- 0002 Richard Krock, Vinyl Institute PH

- H

- 0003 Mary Bachynsky, Formosa Plastics Corpor ation PH

- H

- 0004 Bruce Hollands, PVC Pipe Association

Many of the public comments and the Agency‘s responses are in the preamble to the final standards, and are not repeated here. Table 2

- 3 provides cross

- references to the preamble to identify subjects t hat were commented on and are responded to in the preamble rather than this
document

. Table 2

- 3 . Comments That Are Responded To In the Preamble to the Final PVC Rules

Topic Subtopic Commenters who commented on the topic See the following Preamble

section s for responses2

- 4

Topic Subtopic Commenters who commented on the topic See the following Preamble

section s for responses
Affirmative defense 0150, 0153 V.L
Area sources 0141, 0149, 0153 V.E.2 and V.H. Beyond

- the

- floor analysis PH

- BR

- 003,0144, 0146, 0153 V.F.2, V.F.6, V.M and VI Compliance dates 0144, 0146 IV.B, IV.F, and V.A Definitions and terminolo gy 0142, 0144, 0153, 0146 V.A, V.C, V.F.1 Emission limits, operating limits, and work practice standards 0150 V.C

Equipment leaks Compliance and

monitoring 0146 V.E.2 and V.F.2
Heat exchange systems 0134, 0137, 0141, 0142, 0143, 0144, 0146, 0153, 0160 V.F.5

Impacts General 0155 VI

Cost 0134, 0142, 0144,

0153, 0157 V.E.2, V.H, V.J, and VI

Economics 0124, 0126, 0131,

0135, 0136, 0138, 0139, 0142, 0144, 0147, 0151, 0155, 0158, 0161, PH

- BR

0003, PH

- BR

- 0006 V.J and V.K

Information gathering 0134, 0151, 0144 V.D, V.E.2

MACT floor 0126, 0131, 0134, 0135, 0137, 0144, 0146, 0150, 0153, 0157, PH

- BR

- 011 V.D, V.E.2 and V.J

Miscellaneous PH

- BR

- 007, PH

- H

0002, PH

- BR

- 0002, PH

- BR

- 0005, PH

- BR

0011, 0153 V.B and V.K

Process vents Compliance and

monitoring Closed vent systems and control device bypass CEMS/CPMS Stack testing 0134, 0139, 0141,

0142, 0143, 0146, 0153 V.C, V.E.2, V.F.1, V.G, V.J and IV.J2

- 5

Topic Subtopic Commenters who commented on the topic See the following Preamble

section s for responses Emission limits, operating limits, and work practice Standards Dioxin/Furan limits 0134, 0144, 0142,

0146 , 0141 V.E.2

MACT floor 0118, 0134, 0143,

0144, 0146, 0151, 0153, 0157, 0160 V.D and V.E.2

Vent gas absorbers PH

- BR

- 0001, 0139,

0143, 0142 V.D and V.E.2
Regulatory overlap 0134, 0141, 0142, 0146, 0153 V.B
Regulated pollutants 0137, 0146, 0150, 015 3, PH

- H

- 0001, PH

BR

- 0004, PH

- BR

0010, PH

- BR

- 0011 V.C

Resin 0118, 0134, 0139, 0142, 0143, 0144, 0146, 0148, 0151, 0153 V.C , V.E.2, and V.F.2

Rule comments PH

- H

- 0002, 0141, and 0157 V.B and V.D
Startup, shutdown, and malfunctions General comments,

PRD‘ s, and bypass 0134, 0141, 0142,

0144, 0146, 0153, 0159 V.F.2 and V.J

Statutory and executing orders 0142 V.J and V.K
Subcategories 0134, 0137, 0139, 0142, 0143, 0144, 0146, 0151, 0153, 0157, PH

- H

- 0001 V.D

Variability PH

- BR

- 0002, PH

- BR

0003, 0134, 014 4, 0146 V.D and V.E.2

Wastewater Compliance and

monitoring Relaxed testing for wastewater streams Point of Determination (POD) / Intermittent wastewater 0134, 0141, 0142,

0143, 0144,0146, 0153, 0157 V.C and V.F.4

MACT floor 0134, 0143, 0144,

0146, 0153 V.E.22

- 6

List of Acronyms and Abbreviations
Acronyms

ACC American Chemistry Council ACI a ctivated carbon injections ALAPCO Administration of Local Air Pollution Control Officials APC a ir pollution control API American Petroleum Institute ASME American Society of Mechanical Engineers BWON Benzene w aste o perations NESHAP CAA Clean Air Act CCNJ Council of New Jersey CDD/CDF c hlorinated dibenzo

- dioxins and furans CDF c hlorinated dibenzofuran CEMS c ontinuous emission monitoring system CERCLA Comprehensive E nvironmental R esponse, C ompensation and L iability A ct CFR Code of f

ederal R egulations CMS c ontinuous monitoring system CO c arbon monoxide CPMS c ontinuous parameter monitoring system DQO d ata quality objective dscm d ry standard cubic meter ECD e lectron cap ture detector EDC e thylene dichloride EO Executive O rder EPCRA Emergency P lanning and C ommunity R ight to k now A ct ERT Electronic R eporting T ool FIA f

lame ionization analyzer FIP Federal implementation plan FR Federal R egister ft 3 c ubic feet FTIR Fourier T r ansform I nfrared S pectroscopy GACT G enerally Available Control Technologies or management practices GC FID Gas chromatography flame ionization detector HAP h azardous air pollutants HCl h ydrogen chloride HON Hazardous O rganic NESHAP ICR I nformation C ollec tion R equest IRIS Integrated Risk Information System LDAR l eak detection and repair l/ min l iters per minute2

- 7

m 3 c ubic meters MACT M aximum Achievable Control Technology MON M iscellaneous O rganic C hemical M anufacturing NESHAP MQO m easurement quality objective MS Mass S pectroscopy NAM National Association of Manufacturers NESHAP N ational Emission Standards For Hazardous Air Pollutants NOCS Notification o f Compliance Status NPDES National Pollution Discharge Elimination System NSPS New Source Performance Standar d OCC Occidental Chemical Corporation/OxyVinyls OLD o rganic liquids distribution OSHA Occupational Safety and Health Administration PEG p olyethylene glycol POD p oint of determination ppm p arts per million ppmv p arts per million by volume ppmvd p arts per m illion by volume on a dry basis ppmw p arts per million by weight PRD p ressure relief device PVC p olyvinyl Chloride a nd Copolymers PVCPU PVC Production Process Unit QC q uality control RFCI Resilient Floor Covering Institute ROL r eactor opening loss RQ Repo rtable Quantity RTD r esistive thermal device RVCM r esidual vinyl chloride monomer SAP s ampling and analysis plan SIP State Implementation Plan SPI Society of the Plastics Industry SSM s tartup, s hutdown and m alfunctions STAPPA State And T erritorial A ir P oll ution P rogram A dministrators THC t otal hydrocarbon tpy t ons per year TO t hermal oxidizer TOH t otal organic hazardous air pollutants TOHAP t otal organic hazardous air pollutants UPL Upper Prediction Limit VC v inyl chloride VCHC Vinyl Chloride Health Commi ttee VCM v inyl chloride monomer2

- 8

VGA v ent gas absorber VI Vinyl Institute VOC v olatile organic compound WW w astewater WWW World W ide W eb3

- 1



### 3.0 AFFIRMATIVE DEFENSE

Comment 3.1: The commenter (0153) contended that if an event associated with safety practices c auses a violation and should happen to meet the affirmative defense criteria for malfunctions, the defense should be available. Response to comment 3.1: Both the proposed and final rule provide, as suggested by the commenter, that a facility may assert an affirmati ve defense for a bypass or other event caused by a malfunction that meets the affirmative defense criteria for malfunctions in §63.11895. This is discussed in more detail in section V.F.2 of the final rule preamble.

Comment 3.2 : One commenter (0153) req uested that EPA amend the first paragraph of section 63.11895 to reference enforcement of the ―standards set forth in section 63.11880(a),‖ not ―63.11880‖. They argue that the extensive elements of the affirmative defense in subsections (a)(1)

- (9) should not be required in order to defend against alleged violations of operating limits and other standards referenced in subsections 63.11880(b) and (c), as well as startup and shutdown events which should not be included in §63.11880(a), that do not also invo lve an exceedance of an emissions limit specified in subsection 63.11880(a). Response to comment 3.2: The commenter incorrectly asserts that the elements of the affirmative defense are ―required in order to defend against alleged violations of operating limits
and o ther standards referenced in subsections 63.11880(b) and (c).‖ Section 63.11880 specifies the emissions limits, operating limits and standards that the owner or operator must meet. §63.11880(a) states that the owner or operator ―must comply with each emis sion limit and standard‖ specified in the rule. §63.11880(b) specifies that the owner or operator must ―establish an operating limit for each operating parameter required to be monitored in §§63.11925‖. §63.11880(c) specifies that the owner or operator mus t ―comply with the emission limits and standards specified in §§63.11910 through 63.11980.‖ In establishing this affirmative defense provision, EPA is not removing or restricting any existing ability of source owners or operators to defend against alleged violations of any kind. Instead, we are promulgating an affirmative defense to civil penalties that may be used in addition to any existing defenses that a source owner or operator may have, and we are setting criteria for the new affirmative defense. Th e commenter‘s request to revise section 63.11895 to be limited to ―standards set forth in section 63.11880(a)‖ rather than ―63.11880‖ would result in a more limited availability of the3

- 2

affirmative defense and not fewer requirements for asserting an affirma tive defense, as the
commenter seems to assume. We continue to believe the affirmative defense should be available
for all these standards.

Comment 3.3 : One commenter (0142) contends that some of the requirements in subsections (a)(1)

- (9) are unreason able, difficult to demonstrate, and subject to varying interpretation. Two commenters (0141, 0142) contended that the affirmative defense provisions
that cover malfunctions are too burdensome Response to comment 3.3 : EPA disagrees with comments that critic ize the affirmative defense criteria as being unreasonable, difficult to demonstrate, and subject to varying interpretations. EPA believes that courts are well equipped and often do evaluate and apply the type of criteria set forth is the affirmative defen se. Many of the conditions were modeled after the conditions of the affirmative defense in EPA‘s SIP SSM policy, which several states have adopted into their SIPs. (See, e.g., State Implementation Plans: Policy Regarding Excessive Emissions During Malfunct ions, Startup, and Shutdown (Sept. 20, 1999); Policy on Excess Emissions During Startup, Shutdown, Maintenance, and Malfunctions (Feb. 15, 1983)). We do not have any indication that parties to enforcement proceedings have had any significant
difficulties a

pplying the terms of these SIP affirmative defenses. In addition, EPA‘s view is that use of consistent terms in establishing affirmative defense regulations and policies across various CAA programs will promote consistent implementation of those rules and policies. EPA addresses the burden associated with an affirmative defense by providing the public with an estimate of the relative magnitude of the burden associated with an assertion of the affirmative defense adopted by a source (see section V.L of the preamble). EPA is also providing administrative adjustments to the ICR that include an estimate of the burden of the notification, recordkeeping, and reporting requirements associated with the assertion of the affirmative
defense. We note that the burden e stimate for affirmative defense is less than the burden estimate for the formerly required SSM plan.

Comment 3.4 : One commenter (0141) stated that EPA was silent on its rationale for excluding periods of startup and shutdown from the proposed affirmativ e defense and argued that if EPA refuses to provide separate emission limitations for periods of startup and shutdown, and if in fact excess emissions during these periods cannot reasonably be avoided, there is no3

- 3

reason for EPA not to provide an affirmati ve defense to the source for periods of startup,
shutdown and malfunction. Response to comment 3.4 : EPA is promulgating the affirmative defense for malfunctions only, not for periods of startup and shutdown except that the affirmative defense would be
avai lable if there were a malfunction that occurs during a period of startup or shutdown . EPA believes that malfunction events should be treated differently than periods of startup and shutdown, which are predictable and routine aspects of a source‘s operatio ns. Because startup and shutdown periods are part of a source‘s normal operations, the same approach to compliance with, and enforcement of, applicable emissions standards during those periods should apply as otherwise applies during a source‘s operations . Further, periods of startup and shutdown

– but
not malfunctions

-- are taken into account when establishing section 112 emissions standards. For these reasons, EPA believes it is appropriate to apply the affirmative defense based on the
occurrence of a malfunction and not based on startup or shutdown status. Furthermore, the commenter as provided no information to suggest that excess emissions during startup or
shutdown cannot be avoided.

Comment 3.5 :. One commenter (0142) argued that work practice sta ndards that require the owner/operator to stop the emissions, to stop the malfunction, and to return to normal operations as soon as practical could be established for malfunctions that result in only small levels of excess HAP emissions, instead of requir ing the regulated entity to establish and prove
an affirmative defense. Response to comment 3.5: EPA has determined that CAA section 112 does not require that emissions that occur during periods of malfunction be factored into development of CAA
section 1 12 standards. Accounting for malfunctions would be difficult, if not impossible, given the myriad different types of malfunctions that can occur and given the difficulties associated with predicting or accounting for the frequency, degree, and duration of various malfunctions that might occur. EPA‘s rationale for its approach to malfunctions is not based on the criteria that must be met to justify a work practice standard under CAA section 112(h). Further, setting work practice standards under section 112 p resents the same issues as setting numerical emission limits given the varied nature of malfunctions.3

- 4

Comment 3.6 : One commenter (0142) contended that responding to malfunctions is many
times a case

- by

- case situation depending on the specifics of the ma lfunction and equipment to be repaired, making the language regarding off

- shift and overtime labor unnecessary and confusing.
The use of overtime or off

- shift labor is only one consideration in how to address a malfunction event. If EPA wants to point out that the use of overtime or off

- shift labor must be used, then this language is best included in the preamble rather than the rule itself Response to comment 3.6: Commenter does not explain its view that the language is confusing or explain how its sugges ted language clarifies this provision. Commenter also does not explain its view that the provision is not necessary. The requirement to use overtime labor or
off

- shift labor to make repairs when practicable clarifies what we expect sources to do to meet

t he condition t o make repairs expeditiously.

Comment 3.7 : One commenter (0142) argued that imposing a requirement to print and sign a record of actions in response to the excess emissions (40 CFR 63.11895(a)(7)) is outdated if one can document the response to actions in an electronic format, and thus requested the language be updated to allow for electronic documentation. Response to comment 3.7: EPA accepts documents in electronic format, as long as the format is compatible with the requirements of the sta ndards. The written reports required to demonstrate that the affirmative defense provisions have been met and requests for an extension of the deadline for these reports may be submitted electronically. Owners and operators who
submit documentation for af firmative defense electronically should exercise due diligence to ensure receipt by the Administrator and the delegated permit authority.

Comment 3.8 : One commenter (0142) requested that EPA not require the preparation and
submission of a formal root caus e analysis because this would have a chilling effect on internal communications regarding the root cause investigation and would detract from the goal of ensuring a candid inquiry into the event. They also argued that a regulation of this sort is

unnecessa ry because the cause of even smaller malfunction events is routinely investigated within the industry. Response to c omment 3.8: Commenter does not explain his view that preparation of root cause analysis would chill internal communications, and EPA sees n o reason that requiring such an analysis to be prepared would do so. Indeed, EPA has specified in consent decrees that root3

- 5

cause analysis be conducted and we have never had complaints from the defendants saying that
this chills internal communications.

Comment 3.9 : One commenter (0141) contended that EPA lacks the legal authority to shift the burden to the source to prove by a preponderance of the evidence that it has met all of EPA‘s specified criteria and has taken specified actions (which bear no relation to the statutory factors for performance standards under section 112), in order to avoid ―civil penalties‖, and to do so within 30 days of the event, without even being charged. Another commenter ( 0142)
stated that some aspects of the affirmative defense would make it unavailable as a practical matter for many, if not most, malfunctions since they do not directly relate to the question of
whether an exceedance of the emission limitations due to a malfunction should be excused. For example, the req uirement in proposed §63.11895(a)(8) that the source must show that ―at all times, the facility was operated in a manner consistent with good practices for minimizing emissions.‖ Or, the requirements in §63.11895(b) that the source must notify the Administ rator as soon as possible but no later than 2 working days after the initial occurrence of the malfunction, and must then submit a written report to the Administrator within 45 days of the malfunction that demonstrates, ―with all necessary supporting docu mentation‖ that the source has met each and every factor specified in the proposed affirmative defense. It is unacceptable for EPA to presume that a person has violated the law unless the person has submitted his entire defense in writing before he is even given notice of a potential enforcement action." Response to c omment 3.9: EPA disagrees with comments that criticize the affirmative defense for shifting the burden of proof. The affirmative defense does not require a facility to prove its innocence rathe r than requiring an enforcement authority to prove a violation of the CAA or change the burden of proof with respect to establishing a violation. Further, EPA does not presume a violation unless the reporting requirements are met as commenter suggests. An affirmative defense to civil penalties for exceedances of emission limits that are caused by malfunctions is available to a source owner or operator, but the decision to use the affirmative defense and meet the reporting and recordkeeping requirements rest s with the source owner or operator, who must weigh the cost of meeting the requirements against their perceived need to prepare for assertion of an affirmative defense if a violation is established. The affirmative defense applies to penalties; thus it i s only used where a violation has been established. The burden of proof remains with the plaintiff in an enforcement action. See, e.g., 40 C.F.R. 22.24. If3

- 6

a violation has been established and a source owner or operator wishes to assert the affirmative
def ense with respect to penalties, the source owner or operator bears the burden of establishing
that the elements of the affirmative defense have been met. This burden

- shifting is appropriate because the source owner or operator is in a better position to de termine the facts required to
establish the defense. See , e.g., Arizona Pub. Serv. Co. v. EPA , 562 F.3d 1116, 1120, 1129

- 30 (10th Cir. 2009) (rejecting industry challenge to EPA‘s use of an affirmative defense to address excess emissions during malfunction events). Our judgment is that the affirmative defense criteria capture the appropriate considerations in determining whether penalties are appropriate when a violation occurs as the result of a malfunction. Many of the conditions were modeled
after the conditions of the affirmative defense in EPA‘s SIP SSM policy, which several states have adopted into their SIPs. (See, e.g., State Implementation Plans: Policy Regarding Excessive Emissions During Malfunctions, Startup, and Shutdown (Sept. 20, 1999); Poli cy on Excess Emissions During Startup, Shutdown, Maintenance, and Malfunctions (Feb. 15, 1983)). We do not have any indication that parties to enforcement proceedings have had any significant difficulties applying the terms of these SIP affirmative defense s. EPA notes that the final rule
does not include the 2

- day reporting requirement that commenter criticizes.

Comment 3.10 : One commenter (0141) requests that the language of the affirmative defense be updated to state clearly that a source that quali fies for the affirmative defense shall not be deemed to have violated the applicable standards during that time. Response to c omment 3.10: EPA's approach has been very clear that sources may raise an affirmative defense to penalties only, not to liability. Successful assertion of an affirmative defense would not negate a violation and injunctive relief would be available.

Comment 3.11 : Two commenters (0142, 0153) disagreed with the requirement in subsection (9)(b) to notify the Administrator within two days of an emissions event and to submit a written report within 45 days of an event in order to seek to rely on an affirmative defense. They contended that these requirements are unnecessary due to emissions release reporting required by state agencies, C ERCLA/EPCRA, the EPA Risk Management Program, and OSHA‘s Process Safety Management Standard. They proposed that the information could be included as part of the semi

- annual report required by the Title V Operating Permit reporting

program.3

- 7

Response to c om ment 3.11: We agree with the commenter and have revised the reporting requirement for asserting an affirmative in §63.11895(b) An affirmative defense to civil penalties for exceedances of emission limits that are caused by malfunctions is available to a source owner or operator if he can demonstrate that certain criteria and requirements are satisfied. The criteria ensure that the affirmative defense is available only where the event that
causes an exceedance of the emission limit meets the definition of malfunction in 40 C.F.R. 63.2 (sudden, infrequent, not reasonably preventable and not caused by poor maintenance and or careless operation) and where the source owner or operator took all appropriate actions to
minimize emissions. If a source is in comp liance and does not encounter malfunctions that cause a violation of the standard, we do not expect this activity to be routinely performed by a source owner or operator. The decision to meet the reporting and recordkeeping requirements rests with the

sour ce owner or operator, who must weigh the cost of meeting the requirements against his perceived need to prepare an affirmative defense. However, the rule‘s affirmative defense provisions in §63.11895(b) have been revised to remove the 2

- day notification r equirement. We notification of malfunctions in the report specified in § 63.10(e)(3) that requires the owner or operator to ―submit an excess emissions report‖ to the Administrator semiannually. In addition, we have revised §63.11895(b) in the final
rule to allow an owner or operator of the affected source seeking to assert an affirmative defense after experiencing an exceedance of its emission limit(s) or a violation of an emission standard during a malfunction to submit a written report to the Administrat or in the semiannual compliance report.

Comment 3.12 : One commenter (0142) requested that EPA make the reporting obligations consistent with those outlined in §63.11895 of the rule if the owner/operator opts to
establish an affirmative defense a malfuncti on. They argued that the 10 day reporting obligation is not consistent with other portions of the proposed rule and is also inconsistent with other p art 63 NESHAP. They proposed that the type of information required by §63.11985(c)(8) could also be reporte d as part of the semi

- annual report required in §63.11985 for emissions events that result in an emission quantity that is less than the Reportable Quantity (RQ) established in 40 CFR part 302 or 40 CFR part 355. They argued that inclusion in the semi

- annu al report would streamline the reporting obligations for both regulated entities and regulatory agencies.4

- 8

Response to c omment 3.12: EPA is retaining the 10

- day reporting requirement specified in §63.11915(c)(3). When a malfunction occurs, sources must rep ort them according to the applicable reporting requirements of the subpart . An affirmative defense to civil penalties for exceedances of emission limits that are caused by malfunctions is available to a source if it can
demonstrate that certain criteria an d requirements are satisfied. The criteria ensure that the affirmative defense is available only where the event that causes an exceedance of the emission limit meets the definition of malfunction in 40 C.F.R. 63.2 (sudden, infrequent, not reasonably

preve ntable and not caused by poor maintenance and or careless operation) and where the source took all appropriate actions to minimize emissions. In addition, the source must meet certain recordkeeping and reporting requirements. If a source is in compliance and does not encounter malfunctions that cause a violation of the standard, EPA does not expect this activity to be routinely performed by a source. The decision to meet the reporting and recordkeeping requirements rests with the source, who must weigh th e cost of meeting the requirements against their perceived need to prepare an affirmative defense. These requirements are also similar in nature to the SSM reporting and recordkeeping requirements to which sources were previously subject
, and they require the type of records and reports that sources would already typically keep to demonstrate compliance with the general duty to minimize emissions. However, EPA agrees with the commenter that the 2

- day notification is not needed
because the 10

- day report is required. §63.11915(c)(3) requires that for ―any instance that the release indicator indicates that a pressure relief device is open, you must . . . submit to the Administrator the report specified in §63.11985(c)(8) , This report is required even if you elect to follow the procedures specified in §63.11895(b) to establish an affirmative defense.‖ Therefore, EPA is revising the affirmative defense provisions in §63.11895(b) to remove the 2

- day notification requirement.



### 4.0 APPLICABILITY

Comment 4.1 : Tw o commenters (0153, 0146) requested clarification on the applicability of the rule to wastewater. One commenter (0146) specifically requested that EPA verify that downstream wastewater treatment systems that are not being used to meet emission limits set
f orth in the PVC MACT: (1) are not part of the PVCPU; and (2) are not subject to PVC MACT regulations. The Commenter (0146) requested that EPA allow for exemptions from the4

- 9

wastewater requirements for safety related activities and continue to exempt segrega ted

stormwater. Response to comment 4.1 : In the final rule, we have removed wastewater and process wastewater treatment systems from the definition of PVCPU but added them to the definition of affected source. Affected sources are required to meet the fina l vinyl chloride and total non

- vinyl chloride organic HAP limits for process wastewater before the process wastewater streams are exposed to the atmosphere and before they are discharged from the affected source. In the final rule, we do not specify what t ype of treatment must be used to meet the process wastewater limits. If an affected source chooses to meet the limits by using a wastewater steam stripper, then the limits must be met at the outlet of the treatment system (i.e., the steam stripper). If the streams treated by the steam stripper have met the required limits for process wastewater before being exposed to the atmosphere and before being discharged from the affected source, then there are no further requirements for treatment. Further, if those treated streams that have already met the process wastewater limits are subsequently sent to a secondary treatment process, such as a ―downstream‖ biological treatment system, then there are no additional requirements for
those ―downstream‖ wastewater trea tment systems. In the final rule, we have revised the definition of wastewater to exclude certain safety

- related streams and segregated stormwater. See sections V.F.4 and V.I of the preamble for the final rule for additional detail on the final requirement s for process and maintenance wastewater and for additional rationale for the changes to the final rule.

Comment 4. 2 : One commenter (0139) proposed that EPA simplify subpart HHHHHHH by using the NES HAP for Vinyl Chloride as a framework and adding requirem ents and
definitions for the HAPs limitations. The commenter (0139) contends that this would make the rule easier to understand, because the regulated community is already familiar with this rule. Response to comment 4. 2 : We disagree with the commenter‘s s uggestion. The
framework for developing the MACT standards is section 112(d) of the Clean Air Act, as amended in 1990, not the p art 61 NESHAP , which was developed prior to the enactment of the current 112(d) requirements

. We have, however, harmonized the p rovisions of subpart HHHHHHH with existing provisions of the part 61 NESHAP wherever possible.4

- 10

Comment 4. 3 : Two commenter s ( 0137, 0142) supported EPA‘s proposal that once facilities are in compliance with the final PVCPU MACT, the requirements of the part 61 NESHAP would no longer apply. One commenter (0137) also contended that all part 61 referenced sampling methodologies should be moved to part 63, and any other proposed part 61

cross

- references should be directly incorporated into the final rule. Respon se to comment 4. 3 : In the final rule, we have clarified that once PVC facilities are in compliance with subpart DDDDDD or subpart HHHHHHH then they no longer have to comply with 40 CFR part 61 subpart F. We disagree with the commenter regarding moving

samp ling methods in part 61 to part 63. The sampling methods (EPA Methods 106 and 107) are in part 61 Appendix B of part 61 and are expressly referenced in subparts HHHHHHH and
DDDDDD ; therefore, there is no reason to move the Methods

.

Comment 4. 4 : One comme nter (0150) contended that EPA claims that a ―new‖ source is any source for which construction or reconstruction is commenced ―on or after May 20, 2011‖ 76 Fed. Reg. at 29532 conflicts with the Clean Air Act. The commenter (0150) stated that the
Clean Air Act, makes clear that a new source is one that constructed or modified after the date on which EPA ―first proposed‖ standards for the PVC category. The commenter (0150) stated that the date is not May 20, 2011 but December 8, 2000. Accordingly, the comment er (0150) concluded that any source constructed after December 8, 2000 is a new source and any source reconstructed or modified after December 8, 2000 is a new source. Response to comment 4. 4 : Section 112(a)(4) of the CAA states that a new source is a

stat ionary source if ―the construction or reconstruction of which is commenced after the Administrator first proposes regulations under this section establishing an emissions standard applicable to such source.‖ ―First proposes‖ could refer to the date the EPA first proposes standards for the source category as a whole, or could refer to the date the Agency first proposes standards under a particular rulemaking record, or first proposes the particular standards at issue. We believe that the May 20, 2011, propos al date is the proper date under CAA section 112(a)(4) because the intent of the new source provision is to provide sources with sufficient notice so that new source control requirements can be considered in the initial design. Sources coming into existenc e between the December 8, 2000 , proposal date and the May
20 , 2011, proposal date would have no reasonable means of ascertaining the standards‘ for this final rule and so lacked notice of what controls and strategies to adopt. Because this is5

- 11

antithetical to the policy underlying new source standards, the EPA is maintaining May 20 , 2011, as the date which determines if a source is existing or new. We believe it would be unreasonable to require these sources to comply with the new source limits in this final rule when such limits
were not even available for consideration at the time the units were constructed. We also note that the standards proposed in 2000 and promulgated in 2002 were subject to legal challenge, and subsequently vacated; thus, they by court order, do not exist. Moreover, that rulemaking did not impose new or different standards; it merely reaffirmed the existing part 61 NESHAP standards that already applied. Therefore, the relevant proposal date for determining new source status for
the stan dards in this rulemaking is May 20, 2011.



### 5.0 AREA SOURCES

Comment 5.1 : One commenter (0153) disagreed that all of the technology necessary to meet the MACT limits is generally available. Response to comment 5.1 : We revised our approach to determining GACT in developing this final rule, as discussed in preamble section III.E. In determining what constitutes generally available control technology ( GACT ) for this final rule, we considered the control technologies and management practices that are generally av ailable to PVC area sources by examining relevant data and information, including information collected from the two existing PVC area
sources. We also considered the control options applicable to PVC major sources to determine if the control technologies and management practices used at PVC major sources are transferable and generally available to PVC area sources. See preamble Section V.H. for additional response to Area Sources comments.

Comment 5.2 : One commenter (0153) suggested that instead of combin ing PVC MACT and GACT, EPA could easily promulgate an updated GACT standard using cross

- references to applicable subsections of the PVC MACT and prepare revised GACT requirements (subpart DDDDDD) that minimize the burden on small plants. Response to commen t 5.2 : In the final PVC rules, we have set separate standards for area

source s and major sources. For area sources, which are regulated under subpart DDDDDD, we have updated and added new GACT requirements including the use of cross

- referencing to
sections of the PVC MACT standard s as applicable.6

- 12

Comment 5.3 : One commenter (0149) contended that EPA ‘s proposed use of a refrigerated condenser by CertainTeed to achieve the proposed VC standard for process vents is not technically feasible, because EPA did not account for the process design of CertainTeed‘s bulk manufacturing process. Response to comment 5.3 : As a result of our GACT analysis for the final rule
, CertainTeed is the only area source in the PVC

- only subcategory for process vents and thereby
it s level of control represents GACT for PVC

- only process vents; therefore, their current control technology should be adequate to meet the final rule emission limits. We have also determined that major source testing and monitoring requirements are appropr iate and necessary to ensure
that PVC area sources are in compliance with the process vent standards. See section V.H of the preamble to the final PVC rules for a discussion of the revisions to the area source GACT analysis.



### 6.0 BEYOND

- THE

- FLOOR ANALYSIS

C omment 6.1 : One commenter (PH

- BR

- 0011) was critical of the subjective standard that EPA applied to determine which controls were appropriate and beyond

- the

- floor. One commenter (0137) agreed with EPA‘s conclusion that there are no technically or
economical ly feasible ―beyond

- the

- floor‖ options. A nother commenter (0150) disputed EPA speculation that the technologies sources are already using are generally the most effective. The

c ommenter ( 0150 ) noted that EPA should recognize distinct models of a given cont rol technology (e.g., a fabric filter) as unique controls. This commenter (0150) argued that EPA had not properly demonstrated that existing controls for process vents reflect the maximum achievable degree and therefore not satisfied statutory requirements

. Response to comment 6.1 : We disagree with the commenters ‘ assertions that the
standards used were improper for being subjective and that we did not properly demonstrate that existing controls reflect the maximum level of control achievable . The PVC MACT requirements

were determined following the requirements of the CAA. We first determined the MACT floor
level of control. We then calculated the cost and emissions reductions to identify options that were more stringent than the MACT floor level of control. We made our final determination of
MACT based on our evaluation of cost and emissions reduction for options more stringent than6

- 13

the MACT floor

. For some emission points such as equipment leaks , we determined it was appropriate to go beyond

- the

- floor level of control. For other emission points such as for stripped resins and process vents , we determined it was not appropriate. Commenters did not provide any data to support their assertions that we had not properly conducted the beyond

- the

- floor analys e s

or that EPA did not properly identify or analyze maximum achievable control s

. A detailed discussion of the beyond

- the

- floor analysis is contain ed in the memorandum, ―Revised Beyond

the

- Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category , ‖ which may be found in the docket. We also disagree with the commenter regarding setting MACT floors based on distinctive technologies. In this rule, EPA is using lowest emissions as the measure of best performance (except for those source s where a work practice is more appropriate, e.g., equipment leaks) , irrespective of the types of controls that are being used. This approach is consistent with other MACT standards developed by EPA.

Comment 6. 2 : One commenter (0153) contended that using thermal oxidizers along with VCM absorbers is not practiced in the PVC industry, and to do so would be a beyond

- the

- floor consideration. The commenter (0153) stated that the annualized cost to do so is $190,000/T TOH at PolyOne‘s Henry, Illinois facility and $370,000/T TOH at PolyOne and OxyVinyls Pedricktown, New Jersey facility. Response to comment 6. 2 : We disagree with the commenter regarding setting MACT floors. In this rule, EPA is using lowest emissions as the measure of best performance (except for where a work practice was required, e.g., equipment leaks), irrespective of the types of controls that are being used. As a result, all process vent streams from PVCPUs are included in the MACT floor analysis. This approach is consistent with other MACT st andards developed by
EPA. In the final rule, we are not requiring any particular control technologies be used by
facilities to meet the emission limits. Facilities are free to choose whichever control technology

or measure is appropriate for their particul ar operations, as long as the emission limits are met
and the other requirements in the final rule
, such as those for compliance assurance, are satisfied

. In the final rule, the process vent emission limits and our cost and impacts analyses have been
revis ed. Please see the preamble for the final rule for additional explanation and rationale for
those revisions and the memorandum Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production So urce Category

.6

- 14

Comment 6. 3 : One commenter (0150) argued that because EPA claimed that activated carbon injection was the most effective method for reducing dioxin emissions
, all sources should be required to reduce their dioxin emissions with activated ca rbon. Other commenters (0134, 0146, 0153) contended that activated carbon injection should be considered a beyond

- the

- floor requirement. Commenters (0134, 0153) stated they were unaware of any source with dioxin/furan levels similar to PVC or (0153) simila r equipment configurations or any similar source like a natural gas fired boiler that uses ACI with fabric filter control. A commenter (0153) stated that suppliers indicate that high moisture present in vent gas streams after absorbers may
interfere with r emoval effectiveness of the carbon and filter combination in an acidic environment. The commenter (0153) stated several suppliers of the equipment indicated that development work would be needed to test such an application. Another commenter (0134)
contend ed that high moisture and HCl levels are likely to be technological challenges to the use
of ACI on TO stacks. Response to comment 6. 3 : In the preamble to the proposed rule, we did not claim that activated carbon injection is the most effective method for reducing dioxin emissions. We do recognize, however, that ACI is used in other industries as an effective means to reduce and
control dioxin emissions from combustion sources. In the proposed rule, and in the final rules,
the MACT floor emission levels fo r dioxins and furans are based on the emissions information collected, not on the technology being used. We note that none of the PVC facilities use ACI.
W e did not propose that PVC f acilities must use ACI to meet the dioxin/furan emission limits . In

our e stimate of costs and impacts of the proposed rule (documented in the memorandum, Costs and Emission Reductions for Major Sources in the Polyvinyl Chloride and Copolymers (PVC) Production Source Category) , we calculated the cost of compliance with the MACT emission
limits assuming that ACI would be an applicable technology and could be used to reduce dioxin
and furan emissions. For the final rule, we have revised the MACT floor emission limits for dioxins and furans. See section V.E of the preamble to final PVC standards. We have also revised our assessment of applicable technologies for reducing dioxin and furan emissions from PVC process vents based on the comments received. For the final standards, t he control technologies that would be needed to achieve t he MACT floor levels for process vents (i.e., enhanced recovery) are generally the most effective controls available for reducing VC, HCl, total organic HAP, and CDD/CDF. As documented in the memorandum, Revised Costs and7

- 15

Emission Reductions for Major Sour ces in the Polyvinyl Chloride and Copolymers (PVC) Production Source Category
, f or facilities that needed additional emission reductions to meet the MACT floor limits for all pollutants in both subcategories of process vents, we estimated the cost
for thos e facilities to install an additional refrigerated condenser (i.e., enhanced recovery). As a beyond

- the

- floor option for process vents, we estimated the cost for facilities to meet the final new source limits through the installation of a larger or replace ment recovery system, but still using the same technology. For the reasons stated earlier and because ACI is not a demonstrated technology for controlling CDD/CDF in this industry, we did not assume that ACI would be used to meet the new source process ven t limits. Additionally, based on our beyond

- the

- floor analysis,
we concluded it is not cost effective to go beyond

- the

- floor for CDD/CDF for either process vent subcategory.



### 7.0 EQUIPMENT LEAKS

7.1 Compliance and Monitoring

Comment 7.1.1 : Two commenters (0146, 0 160) requested that EPA provide the option of complying with the subpart UU MACT or 40 CFR part 61, subpart V in the equipment leaks provisions of the proposal. The commenters (0146, 0160) argued that the top five sources are a mixture of both rules, and t hus EPA should provide the option to comply with either monitoring program for all affected sources. Response to comment 7.1.1 : After receiving data corrections concerning control measures applied to equipment leaks at one facility, we revised the MACT flo or analysis for equipment leaks at existing PVC sources. T his revised analysis showed that two out of the best performing five sources comply with 40 CFR part 63, subpart UU level 2 requirements, and the remaining three complied with 40 CFR part 61 subpart V. The subpart UU level 2 requirements are more stringent than the subpart V requirements. Therefore, for the final rule, the MACT floor level of control for equipment leaks at existing PVC sources, taken as the median of the best

controlled five sources , is compliance with 40 CFR part 61 subpart V. We conducted a beyond

the

- floor analysis for equipment leaks at existing major sources and b ased on these results
, we determined that going beyond the floor for equipment leaks at existing PVC major sources i s
cost

- effective based on compliance with 40 CFR part 63, subpart UU level 2 requirements . The7

- 16

MACT floor level of control for new PVC major sources also is compliance with 40 CFR part 63, subpart UU level 2, which we identified as the most effective contr ol of emissions from equipment leaks at PVC facilities

. We did not identify any additional means of control for equipment leaks at new sources that are cost

- effective

. W e are therefore setting the final MACT
standards for new sources at the floor level of control and not going beyond the floor

. This analysis is discussed in the memorandum Revised Beyond

- the

- Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category.

Comment 7.1.2 : One commenter (0153) argued that the monitori ng frequency for leak detection and repair programs required by the rule under subpart UU should be reduced. The commenter (0153) stated that area monitoring requirements were put in place by industry before promulgation. Response to comment 7.1.2: We disa gree with the commenter. Under the part 61 NESHAP, PVC facilities are required to install area monitors as well as comply with the leak detection and repair requirements of 40 CFR part 61, subpart V. As discussed in the previous response, we have determine d that the MACT level of control is equivalent to compliance with 40 CFR part 63, subpart UU level 2, which has specific monitoring requirements. Regardless of whether area monitors are in place
, the compliance requirements from subpart UU are required

to meet the PVC MACT standards.

Comment 7.1.3 : One commenter (0121) pointed out that EPA stated in 76 FR 29533 that ―we are also proposing that, in addition to operating with no detectable emissions, there be no discharge to the atmosphere from any PRD on a ny equipment in HAP service within the PVCPU.‖ The commenter (0121) proposed that upon a discharge to the atmosphere from the PRD that the monitoring requirements specified in 40 CFR part 63, subpart UU for pressure releases from PRD be followed. However, the commenter (0121) pointed out, EPA also stated ―we are proposing that existing and new affected sources comply with the leak detection and repair (LDAR) program requirements of the National Emission Standards for Equipment Leaks

Control Level 2 Standard s, subpart UU of 40 CFR part 63, except for agitators, and rotating or reciprocating pumps and compressors.‖ The commenter (0121) added that for gas and light liquid valves, subpart UU specifies a leak definition of 500 parts per million VOC, and a
monitor ing frequency that is dependent upon the number of leaking valves (76 FR 29533). The7

- 17

commenter (0121) stated that although a leak is defined by subpart UU at 500 parts per million, "no detectable emissions" implies that any detectable emission greater than zero that occurs from a PRD would be a violation, so these conflicting statements need to be reconciled. Response to comment 7.1.3: In preamble Sections IV.E.2. and IV.F.2., we clarify that we are requiring that existing and new affected sources comply w ith the leak detection and repair (LDAR) program requirements of the National Emission Standards for Equipment Leaks

- Control Level 2 Standards, subpart UU of 40 CFR part 63. We are also requiring that, in addition to operating with no detectable emissio ns, there be no direct discharge to the atmosphere from any pressure relief device (PRD) on any equipment in HAP service within the
PVCPU. If a discharge from a PRD is routed through a closed vent system to a control device, the discharge must meet the em ission limits for process vents. We are requiring that, after a
direct discharge to the atmosphere from the PRD, sources must comply with the monitoring requirements specified in 40 CFR part 63, subpart UU for pressure releases from PRD.

7.2 Emission Limits , Operating Limits, and Work Practice Standards

Comment 7.2.1 : One commenter (0157) contended that EPA should revise the 10 ppm HAP limit for double mechanical seals used in rotating compressors in section §63.11915(b)(3) of the proposed rule to be consis tent with the total HAP limit in Table 1 to 12 ppm. The

commenter (0157) asked how the agency derived the 10 ppm HAP limit, wondering if the limit

w ere adopted from the VC NESHAP. Response to comment 7.2.1 : The commenter is correct that the 10 ppm limit in the proposed rule was based on the part 61 NESHAP. We have revised the process vent limits for the
final rules

. See section III for a summary of the changes to the limits. In the proposed rule, we required reciprocating pumps, reciprocating and rotating c ompressors and agitators to be equipped with double seals or the equivalent. In the final rule, we are also allowing affected sources to comply with the requirements for reciprocating pumps, reciprocating and rotating compressors and agitators by complying with the requirements for 40 CFR part 63, subpart UU.

Comment 7.2.2 : One commenter (0120) agreed with EPA‘s proposal to require that new and existing facilities comply with subpart UU, which is also in line with STAPPA/ALAPCO
recommendations.8

- 18

Response t o comment 7.2.2 : We acknowledge the support of the commenters.



### 8.0 HEAT EXCHANGE SYSTEMS

Comment 8.1 : One commenter (0146) requested clarification on the proposed calculation methodology for estimating potential VOC emission s from leaking heat exchange syst ems [40 CFR 63.11920(h)(4)(ii)]. Response to comment 8.1 : We have added an equation in the final rule for estimating emissions from leaking heat exchange systems.

Comment 8.2 : Five commenters (0141, 0142, 0143, 0146, 0160) requested that EPA alter
the fin al rule to account for VOC emissions from non

- PVC sources. The commenters (0141, 0142, 0143, 0146, 0160) contended that r ecycled water in cooling towers can originate from both
PVC MACT and non

- PVC MACT affected sources and there is a potential for low lev els of VOC. In certain locations, sources of clean make

- up water are not available. Additionally, the commenters (0141, 0142, 0143, 0146, 0160) stated that treatment of cooling tower water using
biocides and other additives can also cause elevated VOC read ings which could be detected by the proposed Modified El Paso Method

. The commenters (0141, 0142, 0143, 0146, 0160) added
that t he extremely low leak action levels proposed by EPA present a problem during these normal operations and put the need for essent ial cooling water treatment in conflict with rule compliance. The c ommenters (0141, 0142, 0143, 0146, 0160) argued that EPA should consider alternatives to testing the water return line to the cooling tower. Several commenters (0160, 0153, 0146) suggested that an affected source should be allowed to determine a VOC baseline for recycled water, and then use this value in the calculation of a leak action threshold. One commenter (0142) suggested that owners/operators should be allowed to sample individual hea t exchangers at the inlet and outlet of the closed loop heat exchange system to determine the presence of a leak. The commenter (0142) stated that t his would be similar to the proposed continuous compliance standards for once through cooling water systems at 40 CFR 63.11920(a)(2)(i) and (ii). One commenter (0153) argue d that certain areas of the country with water shortages mandate water recycling. Response to comment 8.2 : In the final rule, we have made some clarifying revisions to the heat exchange syste m rule language. We do not have data available to us , either from8

- 19

commenters or other sources, to substantiate or evaluate commenters' assertions regarding ―baseline‖ levels of VOCs present in cooling water as a result of additives, treatment chemicals,

or recycled water streams. In the final rule, we have revised the leak action levels and monitoring frequencies for heat exchange systems. We have also provided an option in the final rule for facilities to monitor either total strippable VOC or vinyl chlori de in the cooling water . See
section V.F.5 of the preamble for the final rule for additional explanation and rationale.

Comment 8.3 : Three commenters (0143, 0146, 0142) requested that the final rule include additional exemptions for heat exchangers to mak e the proposed rule consistent with other
MACT standards. The commenters (0143, 0146, 0142) specifically cited , the Miscellaneous Organic Chemical Manufacturing (MON) subpart FFFF at 40 CFR 63.2490 and the Hazardous Organic NESHAP (HON) at 40 CFR 63.104(a) (1) through (6) [ subpart F] which exempt heat exchange systems from monitoring requirements if one or more of the conditions are met: 1) intervening cooling fluid containing less than 5 percent by weight of total HAP, 2) once through heat exchange system i s subject to a National Pollution Discharge Elimination System (NPDES) permit, 3) a recirculating heat exchange system is used to cool process fluids that contain less than 5% by weight of total HAP, or 4) once through heat exchange system is used to cool process fluids that contain less than 5% by weight of total HAP. Petroleum Refinery standards ( subpart CC) at 40 CFR parts 63.654(b)(1)(ii) and 63.654(b)(2) have similar exemptions. Response to comment 8.3 : We have clarified in the final rule that heat exc hange systems that are not in HAP service or that have a maximum cooling water flow rate of 10 or fewer gallons per minute are not required to monitor for leaks. In the final rule, in HAP service means that a process component either contains or contacts a liquid that is at least 5 percent HAP by weight or a gas that is at least 5 percent by volume HAP, as determined according to the provisions of 40 CFR 63.180(d). These requirements are consistent with other EPA MACT standards for heat exchange systems. We disagree with the commenter that once through heat exchange systems at PVC facilities should be exempted if they are subject to an NPDES permit. NPDES permits specify discharge limits to water and are not related to the air emissions from the heat exchang e system that result from leaking equipment that are in contact with the heat exchange system.9

- 20



### 9.0 OTHER EMISSION SOURCES

Comment 9.1 : Two commenters (0144, 0153) requested clarification on which HAP containing equipment must minimize emissions by reducing t he volume to the amount that occupies 2% or 25 gallons, whichever is larger; the commenter s (0144, 0153) pointed out that the preamble to the proposed rule under ―5. Other Emission Sources‖ stated the requirement applies to vinyl chloride emissions, yet th e regulatory language (§63.11955) indicates the requirement applies to other HAP containing equipment. One commenter (0144) specifically requested that EPA revise the rule language by replacing total HAP with vinyl chloride to match the preamble language, which they stipulated would simplify compliance as there is already a methodology in place for sampling and detecting vinyl chloride. One of the commenters (0153) requested clarification on measuring methods for demonstrating that equipment opening TOH sta ndard is met. Specifically, the commenter (0153) requested clarification that if Method 21 monitoring instruments are to be used to prove the standard is met, they will need to be calibrated with propane or methane rather than VCM. The

commenter (0153) poi nted out that the reactor opening standard can continue to be controlled by measuring vinyl chloride concentrations or using a volumetric measurement as is done under the existing vinyl chloride NESHAP. One commenter (0139) requested that EPA clarify the standard for reactor opening loss (ROL), proposing that the agency use the specific language from the part 61 NESHAP regulation. Response to comment 9.1 : In the final rule, we have revised the requirement for equipment openings to specify that the quantit y of vinyl chloride must be reduced to an amount that occupies 2% of the containment volume, or 25 gallons, whichever is greater. It is appropriate to continue to set the standards based on vinyl chloride because it will always be present at this
emission point, and controlling it will also control all other HAP. This change was made as the proposed requirement was inconsistent with the similar requirement in part 61 subpart F. All process components and equipment are subject to the equipment opening requi rements; the requirements are not limited to only a subset of process components or equipment. Method 21 should not be used to demonstrate compliance with the equipment opening standard. See section V.F.6 of the preamble for the final rule for additional d etails and rationale.9

- 21

Comment 9.2 : One commenter (0134) requested clarification of the rule language regarding emissions from the unhooking of unloading lines from railcars. The commenter (0134) pointed out that the existing rule recognizes that it is not feasible to reduce VCM concentrations in the unloading hoses to meet the current 10 ppmw, three

- hour average exhaust gas provision and instead requires a work practice standard; however, the preamble does not make this exception clear. The commenter (0134 ) requested that EPA place new language in the ―other emission sources‖ section at proposed §63.11955 as follows, to reflect these standards: (a)(4) Vinyl chloride emissions from loading and unloading lines in HAP service which are opened to the atmosphere after each loading or unloading operation are to be minimized as follows: (i) After each loading or unloading operation and before opening a loading or unloading line to the atmosphere, the quantity of vinyl chloride in all parts of each loading or unload ing line that are to be opened to the atmosphere is to be reduced so that the parts combined contain no greater than 0.0038 m 3 (0.13 ft 3 ) of vinyl chloride, at standard temperature and pressure. (ii) Any vinyl chloride removed from a loading or unloading l ine in accordance with paragraph (a)(4)(i) of this section is to be vented to a closed vent system and control device meeting the requirements in §63.11925. Response to comment 9.2 : In the final rule, we have added a definition for ―miscellaneous vents‖ w hich includes gaseous emissions from loading and unloading lines. Miscellaneous vents are process vents and must meet the requirements for process vents. See the preamble to the final rule for additional explanation and rationale. The requirements for

cont rolling emissions from loading and unloading operations are based on the part 61 standards, which facilities should be in compliance with already.

Comment 9.3 : Two commenters (0139, 0146) requested clarification of the rule language regarding resin stripp ing in the reactor. Specifically, they (0139, 0146) recommended language
from the part 61 NESHAP to clarify that the standard for reactor opening loss (―ROL‖) includes the: ―sum of allowable reactor opening losses, and the emission limit for all downstream equipment (e.g., the stripped resin limits).‖ They (0139, 0146) also stipulated that the vinyl chloride limit in the proposed section 63.11955(b) should include an exception for stripping in the polymerizer similar to the one in the part 61 NESHAP (§61.64 (a)(2)(f)). Response to comment 9.3 : In the proposed and final rule, we have established separate standards for equipment openings and stripped resin. We recognize that part 61 allowed the10

- 22

combination of allowable reactor opening losses and all downstream equipment for purposes of determining compliance with the reactor opening losses standard. The equipment opening standard in the final rule is based on the existing part 61 requirement that the quantity of vinyl chloride remaining in the equipment prior to opening must be reduced to 2% of the equipment containment volume or 25 gallons, whichever is greater. We have retained this requirement in the final rule, but the standard applies to all equipment and process components, not just to
reactors. We do not a gree with the commenter that there should be an exemption for polymerization reactors. Reactor openings have been regulated under part 61 and will continue to be regulated under part 63 subparts DDDDDD and HHHHHHH.

Comment 9.4 : Two commenters (0139, 0146) supported the agency‘s decision to use part 61 NESHAP requirements for vinyl chloride as the pollutant of concern for the polymerizers, as vinyl chloride is the major HAP in the reactor and has the highest partial pressure of all the HAPs known or suspect ed to be in the polymerizer. Response to comment 9.4 : We thank the commenters for their comments.



### 10.0 PROCESS VENTS

10.1 Compliance and Monitoring

10.1.1 General Support of Process Vent Floors and Compliance

Comment 10.1.1.1 : One commenter (153) stated they support reg ulation of HAP emissions from resin production by requiring all vents upstream of the resin strippers to be routed to control equipment. Response to comment 10.1.1.1 : We thank the commenter for their comment.

Comment 10.1.1.2 : Two commenters (0146, 0153 ) stated they support the use of the total organic HAP concept for this MACT rule, rather than individual HAP limits. This would allow individual raw materials and byproducts to change, (0153) depending on customer demand and product innovations, while ove rall emission levels will be capped.10

- 23

Response to comment 10.1.1.2 : We thank the commenter for their support

. The final rule requires affected sources to meet total organic HAP, vinyl chloride, dioxin and furan, and HCl limits for process vents.

Comment 1 0.1.1.3 : One commenter (0153) generally supported the allowance in §63.11935(d) to supplement performance tests with engineering judgment and manufacturer‘s information when setting operating limits for regulated strippers and process vent control equipmen t. The commenter (0153) also generally supported various options for operating parameter combination to use for absorbers and acid gas scrubbers. Response to comment 10.1.1.3 : We thank the commenter for their support

.

10.1.2 General Concerns with Process Vent Floors and Compliance

Comment 10.1.2.1 : One commenter (PH

- BR

- 0011) contended that a problem exists with the process vent floors because EPA set a limit for the threshold that would trigger a vinyl chloride reduction, and then noted that the threshold is a bove any of the capacity of the PVC manufacturers. The commenter (PH

- BR

- 0011) concluded that PVC manufacturers have an exemption from reduction requirements. Response to comment 10.1.2.1 : We are unable to determine what the commenter is referencing

. We pr oposed a vinyl chloride limit , and other limits, that would apply to process

vents without any threshold and not based on capacity. The final emission limit s will apply to all process vent s at PVC facilities

. If the commenter is referring to the calculatio n of the emissions limits incorporating variability, we disagree with the commenter. Consistent with EPA‘s approach on other MACT standards, we have incorporated variability when establishing MACT
floors. See our discussion of variability in the preamble t o proposed rule as well as the
memorandum Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category

.

Comment 10.1.2.2 : One commenter (PH

- BR

- 0011) quoted EPA stating tha t the control technology that would be needed to achieve the proposed MACT floor levels for process vents are generally the most effective controls available for reducing vinyl chloride, hydrogen chloride, total organic hazardous air pollutants, and dioxin s/furans. The commenter (PH

- BR

- 0011)10

- 24

contended that EPA does not require these control technologies; and it does not ensure that such control technologies, even if they were required of the PVC manufacturers, would actually
achieve the maximum emission red uction, which should be the goal of this proposed rule. Response to comment 10.1.2.2 : Generally, our policy in setting MACT standards is not to prescribe a control technology that must be used. W henever possible we set emission limits that
must be met and the source owner or operator has flexibility on the controls that they use to meet the limits. This approach is consistent with the Clean Air Act and with the approaches used to set emission limits based on emissions data from the best performing sources. We disagree with the
commenter that we do not require the most effective controls and do not ensure that the emission
standards are met. The MACT floor and beyond

- the

- floor analyses are contained in memoranda, Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category and Revised Beyond

- the

- Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category
, and the
final rules contain initial and conti nuous compliance requirements that ensure that source owners or operator s are continuously complying with the rule requirements including all applicable
emission limits

.

10.1.3 Closed Vent Systems and Control Device Bypass

Comment 10.1.3 .1 : One commenter (0146) argued that the PVC industry cannot ―immediately comply‖ with section 63.11930(a) through (g), because section 63.11930(h)(2) requires that a closed vent system in vacuum service cannot be returned to vacuum service if the
vacuum is lost. The commenter (0 146) requested that EPA remove this provision for closed vent systems in vacuum service. Response to comment 10.1.3 .1 : In 40 CFR part 63, subpart UU, equipment in vacuum service is exempt from all of the leak detection and repair requirements, including r ecordkeeping and reporting. However, we are requiring demonstration that equipment is in vacuum service, including installation of a pressure gauge and alarm system that will alert an operator immediately and automatically when the pressure is such that th e equipment no longer meets the definition of in vacuum service. While we continue to agree that monitoring the equipment in vacuum service for leaks is not necessary, we find that it is appropriate to demonstrate continuously that your equipment is in vac uum service or comply with the leak detection and10

- 25

repair provisions of 63.1193 0 (a) through (g). With respect to the requirement to ―immediately comply
, ‖ 63.11930(h)(2) specifies that actions to return the closed vent system to vacuum
service must be initi ated, or the source must begin to comply with the leak detection and repair provisions that are promulgated for closed vent systems, which do not operate in vacuum service

.

Comment 10.1.3 .2 : One commenter (0146) stated that if promulgated, the proposed P VC MACT would impose the strictest requirements ever for closed vent systems, [76 FR 29570

- 29573 (to be codified at 40 CFR. §63.11930)] vastly expanding the regulation of closed vents beyond subpart SS by: (1) requiring flow indicators equipped with an ele ctronic alarm system that requires immediate action and results in an automatic violation; (2) making no provision for maintenance activities; (3) expanding the inspection requirements, and (4) failing to provide the exemptions in section 63.983(a)(3) for equipment needed for safety purposes such as pressure relief devices, low leg drains, high point bleeds, analyzer vents, and open

- ended valves or lines.
The commenter (0146) contended that EPA has provided no rationale or explanation for this expansion, or why the current closed vent system requirements under subpart SS are insufficient. The commenter (0146) added that the proposed rule does not provide an exemption for maintenance activities on minor ancillary equipment that may be on a closed vent system, such as opening a low leg drain or a high point bleed, it would be a violation to perform maintenance on the system as ―[a] broken seal...constitutes a violation from the emission limits...‖ [76 FR 29571 (to be codified at 40 CFR. §63.11930(c)(2)(i)).] This i s a contradiction to EPA‘s CAA general duty clause both within this part and part 68, Risk Management Program. Another commenter (0157) stated that in many cases bypass valves on process vent lines are used in order to provide a bleed valve to ensure a saf e work environment when maintenance is being performed on equipment. Response to comment 10.1.3 .2 : In previous rules, equipment that is part of a closed vent syste m ha s been subject to annual monitoring to detect leaks . The final rule contains additional requirements to ensure that emissions streams are properly routed to the closed vent system and delivered to the control device for reduction. The final rule requires you to install and maintain a CPMS for flow through a bypass for each closed vent system bypass line that could divert a vent stream to the atmosphere. The CPMS for flow must be capable of recording the volume of the gas that bypasses the control device and be equipped with an alarm system that will alert an operator immediately and automatic ally when flow is detected in the bypass. These provisions10

- 26

are to ensure that any flow directed through a bypass is detected and identified by the operator. Alternatively, you may secure the bypass line valve in the non

- diverting position with a seal
mecha nism. For this option, you would be required to inspect the seal or closure mechanism at least once per month to confirm that the valve is in the non

- diverting position, or, for a lock

- and

key type lock, maintain records that the key has been checked out. If the alarm sounds or if it is determined during the monthly inspection that a bypass has occurred, you would be required to report a deviation and to include an estimate of the resulting emissions of regulated material that bypassed the control device. O ur intent in this final rule is that control devices will not be bypassed; therefore, use of the bypass at any time to divert a regulated vent stream to the atmosphere would be a deviation from the emissions standards. Additionally, due to the precedent se t forth in the recent court vacatur of the exemptions to emissions standards for startup, shutdown, and malfunction [ Sierra Club v. EPA
, 551 F.3d 1019 (D.C. Cir. 2008)], we

are required to ensure that section 112 emissions limitations are continuous and ap ply at all times. Thus, we are not adopting exemptions for maintenance activities and equipment such as pressure relief devices, low leg drains, high point bleeds, analyzer vents, and open

- ended valves or lines as part of this action. We recognize that equ ipment that is properly designed and
maintained can sometimes fail and that such failure can sometimes cause an exceedance of the relevant emission standard. Thus, for such situations, we ha ve incorporated an affirmative
defense provision which provides f or a defense to civil penalties for emissions exceedances of
standards that are caused by malfunction

.

Comment 10.1.3.3 : One commenter (0141) requested clarification on EPA‘s statement in §63.11915(c) that states ―any release to the atmosphere from a PRD ...constitutes a violation of the rule,‖ and that ―any release‖ will trigger the reporting requirements. They requested that EPA clarify in the final rule that these provisions only apply to releases that exceed the detectable emission level of 500 ppm. One commenter (0142) contended that pressure relief devices are already regulated under the equipment leak provisions in §63.11915(a) which states that the section for pressure relief devices (§63.1030) of subpart UU applies. The commenter (0142) argued that E PA should not regulate the same equipment under multiple sections of the rule. Response to comment 10.1.3.3: 63.11915(c) prohibits direct releases to the atmosphere from pressure relief devices in HAP service and any such a release is an immediate violatio n. However, this requirement is not applicable to leaks which may occur after a PRD has a release10

- 27

because the seal does not reseat properly. To ensure that the PRD is properly reseated, 40 CFR 63, subpart UU requires LDAR monitoring within 5 days of such a release. The PRD must always be operated with no detectable emissions (e.g. 500 ppm above background).

Comment 10.1.3.4 : One commenter (0157) argued that the proposed regulation regarding the automatic notification of a pressure relief device activati ng provides no allowance for the verification that a relief valve discharge did occur. The commenter (0157) argued that the language infers that the deviation occurs and requires reporting even though the activation of the detection device may not indicate a discharge. The commenter (0157) recommended that the proposed rule should include that verification by process history, area monitoring indicators, or other means of actual discharge are incorporated. Response to comment 10.1.3.4: We agree the rule requ ires a release indicator to be properly installed on each PRD in such a way that it will indicate when an emission release has
occurred and to be equipped with an alert system that will notify an operator immediately and automatically when the pressure rel ief device is discharged directly to the atmosphere. We also agree a report is required within 10 days after any instance that a release indicator indicates that a pressure relief device is open. We disagree that such reporting requirement does not allow

v erification of a release or that it improperly implies that a deviation occurred. The requirements for automatic notification to the operator and a 10 day report to the agency are based on the PRD being open, as detected by the release indicator. These re quirements apply independently of any effort by the operator to verify that a PRD discharge occurred. Further, under the rule a deviation includes when a PRD discharges directly to the atmosphere. If the PRD release indicator is functioning as required by the rule, the requirements for automatic notification and reporting will only apply when a PRD has discharged directly to the atmosphere. These requirements are designed to alert the operator and inform the agency so that appropriate action can be taken to
address the source of the PRD release. For these reasons, verification by process history, area monitors or other means of actual discharge is not necessary.

Comment 10.1.3.5 : One commenter (0157) pointed out that the Vinyl Chloride NESHAP provided for an alternative to deviation from the rule for relief valve discharges by allowing relief valve discharges to be ducted to a flare meeting the conditions of §60.18(d) and (f). The commenter (0157) stated that recognizing this type of control for relief val ve discharges fails to10

- 28

recognize that the flare would certainly control organic HAP to a level exceeding 98%. The commenter (0157) contended that looking at organic HAP fails to recognize the HAP emissions likely produced by the combustion of vinyl chlorid e in the form of hydrogen chloride (HCI). Thus, the commenter (0157) argued, EPA should include provisions for the treatment of HAP relief valve discharges to a flare and incorporated into the final rule similar to the language in §61.65(d)(2). Response to comment 10.1.3.5 : We disagree with the recommendation to allow emissions
from relief valves at PVC facilities to be ducted to a flare. Because of the chlorine that exists in the vent stream and potential formation of dioxin, we have prohibited the use o f flares to meet the emission limits in the final rule. According to the data received in the PVC CAA section 114 survey, there are no flares in operation within the PVC industry. Some facilities route their PRDs into a gasholder or a closed vent system t hat is sent to a control device. In doing so, the PRD releases are part of the process vent stream and are subject to the process vent emission limits in Table 1 or 2 of the regulation.

Comment 10.1.3.6 : One commenter (0141) argued with EPA‘s reasoning for requiring
the installation of electronic indicators on each PRD. The commenter contended that in addition to the operational and safety reasons for closely tracking PRDs, the Part 61 NESHAP requires that PVC plant owners or operators submit a report wi thin 10 days of every PRD release that provides information on the date, time, and duration of the release, along with the source, nature, and cause of the release. The commenter pointed out that PVC plants are also required to estimate the approximate emi ssions during the discharge, report the method used for determining the HAP emitted, include a description of the actions taken to prevent the discharge, and describe measures adopted to prevent future discharges. The commenter argues that these reports ha ve provided EPA with years of data to allow for a rigorous analysis of the emissions from PRD releases and yet, the proposed rule provides no basis for the conclusion that there are significant
HAP releases from PRDs. Response to comment 10.1.3.6: The resp onses to these comments are in Sections V.F.2 and V.J of the preamble to the final PVC rules. We disagree with the commenter that reports of PRD discharges have been provided to us. We also requested this type of information in the Section 114 survey reque sts and received no indication that any such releases occurred over the time period requested.10

- 29

Comment 10.1.3.7 : Two commenters (0143, 0146) argued that EPA should remove the provision subjecting PVCPUs to automatic violations of the rule due to a bypass occurrence. The commenters (0143, 0146) argued that the agency has never provided for automatic violations if flows are detected or if the manual valve is opened. The commenters (0143, 0146) added that under the proposed rule, for each closed vent system t hat contains a bypass, a PVCPU would automatically be in violation of the rule if any emissions are discharged to the atmosphere through the bypass. [76 FR 29570.] Commenters (0141, 0143, 0146) argued that this proposed provision, including vacuum service indicators, is overly broad and does not provide the only assurance that a flow directed to a bypass will be detected and addressed. The commenters (0141, 0143, 0146) added that under other Clean Air Act ("CAA") regulations, the agency has required install ation of flow indicators that are capable of taking periodic readings to address bypass monitoring and require that visual inspections of the seal or closure mechanism are performed at least monthly. [See 40 CFR 63.114(d); see also 40 CFR 63.983(a)(3)]. On e commenter (0146) contended that if a control device is bypassed, that does not automatically mean that a violation occurred, such as the case where the PVCPU did all it could to prevent the release, but the cause of the release was outside of the Unit‘s control (e.g., direct lightning hit; terrorist attack; catastrophic mechanical failure, etc). The commenter (0146) concluded by stating if no design, maintenance, or operational error is involved in a bypass, these limited
circumstances should not be viola tions subject to penalties. One commenter (0157) requested the agency clarify that the requirement to maintain the bypass in the closed position is only required when the closed vent system is actually in HAP service (i.e., not applicable after the line ha s been cleared in accordance with §63.11955). One commenter (0146) argued that under the Part 61 NESHAP, PVCPUs currently are prohibited from bypassing a control device, unless specific federally enforceable exemptions apply (e.g., emergency manual vent v alve discharges and emergency relief discharges). The commenter (0146) stated that as such, PVCPU have operating procedures and mechanisms in place to prevent bypasses. The commenter (0146) added that as seen in the HON and subpart SS,
installation of flow indicators and visual inspections ensure that operators are aware and can address any issues involving flows to a bypass; automatic violations of the rule will not necessarily ensure that a flow directed to a bypass is detected. The commenter (0146)10

- 30

recom mended that EPA should remove the provision subjecting PVCPUs to automatic violations
of the rule. Response to comment 10.1.3.7 : As one commenter stated, bypass of a control device at PVC facilities is already prohibited under the Part 61 regulations, exc ept for certain emergency discharges. The final rule specifies that bypass means to divert a process vent or closed vent system stream to the atmosphere such that it does not first pass through an emission control device. The rule provides that a vent stre am within a closed vent system must not be discharged to the atmosphere through a bypass. Section 63.11930(c) further provides that any such release constitutes a violation. We agree with commenters that the installation of flow indicators and the inspecti on, leak monitoring and repair provisions of this rule ensure that operators are aware and can address any issues involving flows to a bypass, including initiating repairs. These steps should avoid or minimize the bypassing of control devices. However, for this final rule, we have identified no basis to exempt bypasses from otherwise applicable requirements. The continuous use of a control device is necessary to meet the process vent limits; therefore, bypasses diverting vent streams away from the control d evice necessary to meet the emission standards and directly discharging to the atmosphere are in violation of the rule. These requirements are consistent with the Clean Air Act‘s mandate that emission standards continuously apply. We believe that most byp asses from closed vent systems are caused by malfunctions or other occurrences (e.g., poor design, improper maintenance, or operational error) that do not justify an exemption from standards that, under the CAA, apply continuously. For closed vent systems in vacuum service, we have specified that a violation has occurred only if the vacuum system alarm sounds and the closed vent system is not also meeting the requirements for closed vent systems not in vacuum service specified in 40 CFR 63.11930 of the fina l rule. We have also specified that each closed vent system must be designed and operated both to collect any gas or vapor HAP from each continuous process vent, miscellaneous process vent and batch process vent, or process component, and to route the col lected vapors to a control device, regardless of whether the closed vent system is ―in HAP service.‖ The rule requirements specify that each process stream, including gas or vapor HAP removed in accordance with §63.11955, must be
routed to a control device ; therefore, the bypass must remained closed. These requirements have been structured to ensure that the emission standards apply at all times. For this final rule, we are including an affirmative defense to civil penalties for violations
that are caused by malfunctions, including bypasses from closed vent systems that are caused by10

- 31

malfunctions. See 40 CFR 63.12005 (defining ―affirmative defense‖ to mean, in the context of an enforcement proceeding, a response or defense put forward by a defendant, regar ding which the defendant has the burden of proof, and the merits of which are independently and objectively evaluated in a judicial or administrative proceeding). We also are requiring other regulatory provisions to specify the elements that are necessary to establish this affirmative defense; the source must prove by a preponderance of the evidence that it has met all of the elements set forth in 40 CFR 63.11895. (See 40 CFR 22.24.) The criteria ensure that the affirmative defense is available only where t he event that causes an exceedance of the emission limit meets the narrow definition of malfunction in 40 CFR 63.2 (sudden, infrequent, not reasonably preventable and not caused by poor maintenance and or careless operation). Therefore, instances where a b ypass from a closed vent system is beyond the unit‘s control would be addressed by the affirmative defense. If a bypass occurs, it will be considered a violation, but the source is provided the opportunity to present an affirmative defense to civil penalti es.

Comment 10.1.3

. 8 : One commenter (0153) stated that closed vent systems §63.11930(e)(1) indicate that leaks can be detected by Method 21 monitoring or by visual inspection. The commenter (0153) argued that sometimes, audio and olfactory methods are a lso effective and the option to use these devices should be added to the rule. Response to comment 10.1.3

. 8 : The final rule requires sources to comply with the equipment leak standards in 40 CFR part 63 subpart UU level 2. The subpart UU level 2
standards have requirements for instrument and sensory monitoring of leaks. Sensory monitoring includes visual, audible, olfactory, or any other sensory detection method used to determine a potential leak to the atmosphere.

10.1.4 CEMS/CPMS

Comment 10.1.4.1 : A commente r (0142) argued that EPA‘s requirement for new sources to use CEMS ignores cost and technical applicability. The commenter (0142) stated that the requirements may not result in environmental benefits and may lead to high costs for implementation of inappro priate and unreliable technology. The commenter (0142) argued that CEMS requirements should be revisited at the 8

- year review. At that point, EPA may have some10

- 32

information on the cost, efficacy and reliability of these systems as applied to PVC MACT

source s. Response to comment 10.1.4.1 : While we disagree with the commenter‘s suggestion s that
CEMS are costly and unreliable, the comments are moot, as the final rule does not require CEMS use. Our experience is that many source owners or operators find the fl exibility and certainty afforded by CEMS use well worth their cost, and we encourage source owners and operators to continue to explore the benefits of CEMS use.

Comment 10.1.4.2 : A commenter (0142) agreed with existing source option for CEMS, periodic te sting or CPMS. The commenter (0142) stated that the regulatory flexibility allows existing sites to select the most appropriate, cost

- effective compliance method. Response to comment 10.1.4.2 : We appreciate the commenter‘s support for the rule‘s
monitorin g flexibility.

Comment 10.1.4.3 : One commenter (0142) argued that EPA should base compliance on daily average parameter values. The commenter (0142) stated that t hree

- hour block averaging for parameters being monitored using a continuous parameter monito ring system is inconsistent with
most other part 63 NESHAP

. The commenter (0142) added that m ost part 63 NESHAP allow for use of a daily average value when demonstrating compliance with continuous monitoring system requirements (for example, fire box tempe rature for a thermal oxidizer). To be consistent with
other part 63 NESHAP , the commenter (0142) recommend ed using a daily average for demonstrating compliance with continuous monitoring parameters. Alternatively, the commenter (0142) stated that at a mini mum , EPA should specify that if the control device is already governed by another MACT standard, the averaging time specified under that MACT standard is controlling. The commenter (0142) stated that EPA should update the following regulatory
sections and Table 6 of the proposed rule to allow for daily average data averaging periods for parameters monitored on control equipment rather than three

- hour data averaging periods:

§63.11890 What are my additional general requirements for complying with this subp art? (d) (3) When a 3

- hour block daily average from a continuous emissions monitor, as required by §63.11925(c), exceeds an emission limit in Table 1 or 2 to this subpart10

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§ 63.11925 What are my initial and continuous compliance requirements for process

ve nts? (d)(4) For each emission limit for which you use a CEMS to demonstrate compliance, you must demonstrate initial compliance with the emission limits in Table 1 or 2 to this subpart based on 3

- hour block daily averages of CEMS data collected at the mini mum frequency specified in §§ 63.11935(b)(2) and 63.11890(c), and calculated using the data reduction method specified in § 63.11935(e). For a CEMS used on a batch operation, you may use a data averaging period based on an operating block in lieu of the 3

- hour daily averaging period. (e)(3)(ii) You must demonstrate continuous compliance with the emission limits in Table 1 or 2 to this subpart based on 3

- hour block daily averages of CEMS data, the minimum data collection frequency specified in §§ 63.11935(b) (2) and 63.11890(c), and the data reduction method specified in § 63.11935(e). For a CEMS used on a batch operation, you may use a data averaging period based on an operating block in
lieu of the 3

- hour daily averaging period.

§ 63.11985 What notificatio ns and reports must I submit and when? (b)(4)(i)(A) For CEMS, the 3

- hour block daily average value calculated for any period when the value is higher than an emission limit in Table 1 or 2 to this subpart or when the
value does not meet the data availabil ity requirements defined in § 63.11890(c). (b)(5)(iv)(C) The frequency and content of monitoring, recording, and reporting if monitoring and recording is not continuous, or if compliance reports, as specified in paragraph (b)(4)(i)(A) of this section, wil l not contain 3

- hour block daily average values when the monitored parameter value does not meet the established operating limit. The rationale for the proposed monitoring, recording, and reporting system must be included.

TABLE 6 TO SUBPART HHHHHHH OF PA RT 63

— OPERATING PARAMETERS, OPERATING LIMITS, AND DATA MONITORING, RECORDING, AND COMPLIANCE FREQUENCIES FOR PROCESS VENTS, STRIPPED RESIN, AND
WASTEWATER

- Delete all references to ―3

- hour block‖ in this table and replace with ―daily averages.‖ Response t o comment 10.1.4.3 : The rule retains 3

- hour block average parameter monitoring, remaining consistent with the 3

- hour averaging period of the existing vinyl chloride10

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NESHAP. Should an owner or operator wish to rely on just one averaging period,, he or she could submit an alternative monitoring request to the Administrator in accordance with §63.8(f).

Comment 10.1.4.4. : One commenter (0151) requested clarification on how to establish batch operation conditions for the regulated HAPs that are consistent wit h §63.11945(b) and (c), which require that performance testing must be done at the ―absolute worst

- case conditions or hypothetical worst

- case conditions‖. Response to comment 10.1.4.4 : As provided in the rule, a source owner or operator is required to cond uct performance testing for vents using conditions that provide for the most challenging conditions for the control device . For a unit with batch process operations, §63.11945(c)(3) requires the source owner or operator is to determine the worst

- case emis sions profile for the vent to the control device. Should a source owner or operator have emissions test data, he or she must follow the instructions in §63.11945(c)(1)(i) or §63.11945(c)(1)(ii) to
determine absolute worst

- case conditions. In addition, a source owner or operator must follow the instructions in §63.11945(c)(3)(ii) or §63.11945(c)(3)(iii) to determine hypothetical worst

case conditions. The source owner or operator must then conduct performance testing under the conditions, whether absolute or hypothetical that provides maximum emissions.

Comment 10.1.4.5 : One commenter (0153) requested that §63.11950 be deleted. As an alternative, the commenter requested clarification regarding how §63.11950 applies to a PVC plants and what equipment it wa s intended to control. The commenter (0153) questioned the extent to which the section was intended to overlap with any batch vents, such as ones that use controls to meet the VCM limit that also control other organic HAPs. Response to comment 10.1.4.5 : We disagree with the commenter‘s suggestion to remove §63.11950 from the rule, for that section contains the equations that source owners or operators are to use to determine emissions profiles from selected activities. Engineering assessments are
to be use d to determine emissions profiles from other activities, per §63.11950(i). As mentioned in §63.11925(g)(1)(ii), the procedures in §63.11950 are to be used to determine the emissions profile from batch process vents.

HCl CEMS10

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Commen t 10.1.4.6 : One commente r (0146) contended that EPA should remove the HCl CEMS requirement from the rule and only require CPMS for continuous compliance. Another commenter (0153) stated that an HCl CEMS requirement is premature until the technology is
available. One commenter (0 153) contended that if new plants require HCl CEMS, accuracy limitations must be factored into emission limits as they were for the Portland Cement MACT due to FTIR Method 321 limitations. The commenter (0153) added that there is little point in installing a CEMS if all the values are below the limits of detection. Two commenters (0146, 0153) argued that it is unclear whether current HCl CEMS technology can demonstrate compliance with the proposed new plant limits. A commenter (0153) stated that they are n ot aware of any PVC facilities using HCl CEMS. The commenter (0153) contended that if there are other sites reliably measuring HCl in wet stacks at levels below 80 ppb, EPA must add that information to the record. If not, EPA must set the new plant HCl

sta ndard at a level that a HCl CEMS can accurately measure or not require HCl CEMS for new plants. Commenters 0146 and 0153 stated that it is also unclear whether the required accuracy is available from the proposed stack test specified in Method 26A. One com menter (0146) argued
that EPA should re

- evaluate the HCl CEMS cost estimate. The commenter (0146) stated that
EPA estimated cost for initial installation of HCl/O 2 CEMS using the EPA CEMS estimator is $165,635. [The costs are reported in 2007 dollars.] The commenter (0146) added that EPA annualized cost over 10 years including 7% interest, annual certifications, recordkeeping, and reporting, is $50,897 ; t hese costs are based on installation at an existing facility, addition of one new platform, and no CEMS currently being installed. The commenter (0146) added that t he cost
for THC/O 2 CEMS under the same assumptions is roughly the same ; f or installation of both monitoring systems, the initial cost would be $189,909 with an annualized cost over 10 years of $59 ,686. The commenter (0146) stated that b eyond 10 years, the projected annual cost for operation, maintenance, and reporting for the CEMS is estimated at $27,310. None of these values have been adjusted for inflation. Response to comment 10.1.4.6 : In the fi nal rule, we are not requiring HCl CEMS but are provid ing for HCl CEMS as a compliance option once performance specifications specific to HCl are promulgated. See section V.G of the preamble to the final rule for additional explanation
and rationale.10

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Comm ent 10.1.4.7 : One commenter (0153) stated that paragraph (b)(6)(i) refers to minimum accuracy and calibration requirements that do not exist. Another commenter (0146) stated that no performance specification is available for HCl CEMS, and it is unclear wha t periodic Relative Accuracy tests will be needed and the cost for conducting those tests. The commenter (0146) added that the proposed rule does not specify the instrumentation principles of the HCl monitoring equipment n addition, the commenter would ult imately like the HCl CEMS requirement removed. The commented (0146) stated that t hough the measurement range of HCl CEMS should be able to reasonably show compliance with the proposed 150 ppmvd limit for existing units, it is unclear whether the current te chnology can demonstrate compliance with the proposed new plant limit of 0.17 ppmvd. The commenter (0146) recommended that EPA remove CEMS for HCl and only require a CPMS approach for continuous compliance
determination. Another commenter (0153) stated tha t they are not aware that EPA‘s Advanced Monitoring Systems Center has published any verification studies using this monitoring technology for wet gas streams. Response to comment 10.1.4.7 : While HCl can be measured with FTIR CEMS, which have a promulgate d Performance Specification (15), we agree with the commenter that there are no promulgated performance specifications for CEMS specific to HCl; for this reason, the rule no longer requires use of HCl C EMS and the comments are moot.

VCM CEMS

Comment 10.1. 4.8 : Three commenters (0134, 0143, 0146) stated that EPA should continue to allow continuous emissions monitoring (CEMS) for VCM. Some commenters (0141, 0143, 0146) stated that VCM CEMS have been in use for the last 35 years. Commenters ( 0134
and 0146 ) arg ued that monitors provide real time emissions data, and commenters ( 0134 and
0143 ) added that since monitors provide real time data, CEMS should be allowed in lieu of CPMS for thermal oxidizers, eliminating the need for less direct parameter monitoring.
Co mmenters (0134, 0141) stated that any steps taken to control VCM in the TO outlet will also control the other organic HAPs as well. They (0141, 0146) argued that VCM CEMS provides the best indication of control equipment performance. The commenter (0146) d escribed how bond enthalpy analyses can be used to predict the destruction of other HAP based on the destruction of VCM. Commenters (0141, 0146) also added that real time emissions monitors are preferred by EPA and the general public.10

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Several commenters ( 0134, 0141, 0143, 0146) contended that with VCM CEMS, stack testing for total HAP or total hydrocarbons should be required every five years. Some commenters (0141, 0143, 0146) stated that with VCM CEMS, VCM stack testing should no longer be required.
Three commenters (0141, 0143, 0146) contended that EPA did not provide a rationale for the removal of VCM CEMS in the proposed rule. A commenter (0146) stated that, at the June
30 th , 2011 EPA and Working Group Meeting, EPA indicated VCM CEMS were not incorporat ed due to the lack of a readily available performance standard. The commenter (0146) expressed confusion, stating that a 1985 EPA review of CEMS and CPMS monitors found that both types of monitors tested in the field were reasonably accurate in the 2

- 10 pp m range. The commenter (0146) noted that they understand accuracy limitations; however, local and state air agencies
would not allow for the discontinuation of VCM CEMS. Several commenters (0141, 0143, 0146, 0153) argued that the final PVC MACT rule

must allow for the continued use of existing vinyl chloride continuous emission monitoring system ("CEMS"), with an option to substitute a total hydrocarbon ("THC") CEMS, similar to the existing vinyl chloride NESHAP . The commenters stated (0143, 0146, 0153) th at continuous vinyl chloride monitoring equipment has been used on process vents for the last 35 years and EPA has presented no reason for why the current CEMS requirement has been removed from the proposed rule. Two commenters (0143, 0153) added that even if the rule is silent on these monitors, it is unlikely that state agencies would allow PVC plants to discontinue their use. Several commenters (0146, 0153) stated that emission monitors yielding real time emission data are typically a preferred approach by EPA and the public. A commenter (0153) stated emission monitors are generally accurate and economical. Commenters (0146, 0153) stated that EPA personnel indicated verbally that continuous vinyl chloride monitors were not incorporated into the proposed rule because a performance specification was not readily available for use; however, based on the 1985 EPA Environmental Systems Monitoring Laboratory (EPA/600/S4

- 85/037) review, these monitors were reasonably accurate in the 2

– 10 ppm range. The commenter (0153) added that manufacturer‘s specifications can also be used to maintain and calibrate these monitors. The commenters (0146, 0153) stated where continuous vinyl chloride monitors are used, they provide a very good indicator of (0146, 0153) proper
therm al oxidizer operation or (0146) absorber operation. Vinyl chloride as measured by our current monitors is the best existing indicator of whether (0153) our control processes and (0146)10

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control equipment (oxidizers and absorbers) are functioning properly. T he commenters (0143, 0146, 0153) concluded stating that where existing real time vinyl chloride monitors are used, (0143, 0146) VCM stack testing is not needed or (0153) facilities should be exempt from the requirement to conduct VCM stack tests and, (0146 , 0153) no other frequent TOH/THC stack testing or (0143, 0146, 0153) CPMS is needed and stack testing for TOH/THC should only be required once every five years. Response to comment 10.1.4.8 : We find the commenters‘ view regarding the existence of vinyl ch loride (VC) continuous emissions monitoring systems (CEMS) mistaken. The VC NESHAP requires a VC monitoring system, not VC CEMS for major leak detection (see §61.65(b)(8)(i)) and for emission monitoring (see §61.68(a)). Source owners and operators subject to that rule are to propose an instrument operations program acceptable to the Administrator for major leak detection and to propose a daily span check with a span of 10 parts per million (ppm) for emissions monitoring. Since neither type of VC monitorin g system contains the complete components associated with a performance specification, examples of which can be found in Appendix B of 40 CFR part 60, the VC monitoring system mentioned by the commenters and required by the VC NESHAP is not a VC CEMS.
Whi le we prefer use of CEMS when available, the rule does not include VC CEMS because there are no promulgated performance specifications for VCM CEMS. Moreover, we believe existing VC monitoring systems may have difficulty accurately measuring emissions for three of the four process vent emissions limits because the VC monitoring systems were designed for an emissions limit of 10 ppm, some 9 times larger than these rule limits. More specifically, the EPA document cited by the commenters bolsters our belief, as it notes ―...when the combustion level dropped to below 1 ppm in the sampling line, the relative accuracy became far worse (approximately 30%)...,‖ which is some 50% larger than the most generous relative accuracy allowed in performance specifications and t hree times as large as the reported relative accuracy for VC concentrations between 2 and 10 ppm. Even though commenters provided no data to support the present availability of monitoring systems that can provide accurate measurements at low levels, should such systems exist, a source owner or operator would be able to submit to the Administrator an alternative monitoring request to use such a system, in accordance with §63.8(f). We have no control over local, state, or tribal air agencies who act according to their own authority for a program, so a state agency may not allow an owner or operator to discontinue10

- 39

existing vinyl chloride monitoring. We agree that ongoing, periodic emissions testing apart from RATAs for units subject to CEMS requirements is redu ndant, and, as shown in §63.11925(e)(4), the rule has been revised to require ongoing, periodic emissions testing only from those units not using CEMS to demonstrate compliance.

CPMS

– Calibration frequency and feasibility

Comment 10.1.4. 9 : Two commenter s (0142, 0153) requested that EPA allow calibrations of CPMS monitoring equipment based on generally accepted good engineering practices and manufacturer‘s recommendations. Both commenters (0142, 0153) contended that the annual calibration requirements in Table 8 are not reasonable given normal operating and turnaround practices and manufacturer‘s recommendations. One commenter (0153) stated that the proposed calibrations schedule is too frequent for some applications (e.g., calibrating some pH meters

every 8 hours). One commenter (0142) indicated that annual inspection of flow rate, conductivity, and pressure monitors for mechanical integrity and electronic error logging is achievable; however, straight calibration is not. Both commenters (0142, 0153) conte nded that, for most of these instruments, calibration will require removal of the device and transfer to an appropriate facility. One commenter (0142) indicated that this type of activity would have to be performed during facility turnarounds, and that tur narounds are typically scheduled at 3 year intervals, not annually. The commenter (0142) expressed concern that, in order to meet the proposed calibration requirements, piping and instrumentation would have to be redundant in
order to allow removal of the device while the facility is in operation. The commenter (0142) stated that, in many instances, calibration requires the removal of the device, which in turn requires a shutdown of the process, and that many sources do not routinely shut down their

process equipment or air pollution control equipment on an annual basis. The commenter (0142) further explained that this is especially true when the control device is used by more than one
source. The commenter (0142) argued that mandating an annual shutdown wou ld require the clearing and cleaning of equipment in preparation for maintenance, which introduces more opportunities for excess emission events. Response to comment 10.1.4. 9 : We disagree with the commenter‘s assertions that CPMS
calibration is unreasonabl e or too difficult to perform annually, as well as more frequently for pH monitors. Since parameter monitoring is at least one step removed from direct emissions10

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measurement, one must be certain that the values obtained from the parameter monitoring, both initially and on an ongoing basis, remain comparable over time. Showing that the monitoring system continues to operate properly, in that it responds as expected, or, in other terms, it remains calibrated is paramount. The rule‘s frequencies for ensurin g that the instrumentation and the system remain appropriate are the minimum we expect to be practical, as well as workable. Note that we seek verification that the monitoring system continues to perform well; such verification could come from comparisons to a redundant monitoring system (as mentioned by one commenter), from an established program of frequent sensor replacement, as well as via what the commenters refer to as a ―straight calibration.‖ Of course, should an owner or operator
desire to use a different technique, he or she is able to submit an alternative monitoring request to the Administrator in accordance with §63.8(f).

Comment 10.1.4.1 0 : One commenter (0142) argued that EPA should not specify a calibration frequency (or, in some instances, specify calibration at all) for temperature and flow rate monitors, considering modern instrument technology and generally accepted good engineering practices. The commenter (0142) explained that, historically, temperature devices such as thermocouples re quired periodic verification (which is not the same thing as ―calibration‖) because of the cold junction compensators, and that it would not have been possible to ―calibrate‖ the thermocouples as they have no adjustment mechanism. The

commenter (0142) expl ained that, rather, the appropriate practice would have been to dispose of thermocouples that fail verification, and replace them with new thermocouples; so, even for these devices, a ―calibration‖ requirement would be inappropriate. The commenter (0142) further contended that annual calibration of passive temperature devices such as platinum resistive thermal devices (RTD‘s) is inappropriate, as, not only do these devices lack an adjustment mechanism (so that they cannot actually be ―calibrated‖), but the y also rarely ever fail. Consequently, the commenter explained, replacement of an RTD is a very infrequent (not annual) task, and replacing RTDs every year would be a waste of money. The

commenter (0142) continued that, when an RTD does fail, it does not j ust drift to a slightly higher or lower value than the true temperature, which is the type of failure that ―calibration‖ is intended to address; rather, RTDs fail all at once (full scale high or low). The commenter (0142) argued that a more reasonable reli ability strategy for RTDs, based on good engineering practice, is the periodic replacement of the device, but not necessarily annually.10

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The commenter (0142) further explained that many other temperature or flow measurement devices are designed with ―smart ‖ electronics which offer continuous diagnostic checks as a verification that the device is operating properly. The commenter (0142) argued that ―calibration‖ may not be needed for these devices; rather, at most it might be appropriate to check the diagnos tic routines and verify that they are functioning as intended. The commenter stated that this would not be a ―one size fits all‖ requirement. The commenter (0142) further stated that, in instances where redundant devices are installed, the ability to cross check measured values against one another is adequate as a validation of proper operation, and, as a result, it may not be necessary to ―calibrate‖ these devices on the same schedule as a ―non

redundant‖ device that operates on its own. Response to comme nt 10.1.4.1 0 : We disagree with the commenters‘ suggestions that temperature and flow rate minimum calibration requirements need not be provided in the rule. As mentioned earlier, since parameter monitoring is at least one step removed from direct
emission s measurement, one must be certain that the values obtained from the parameter monitoring, both initially and on an ongoing basis, remain comparable over time. Showing that the monitoring system continues to operate properly, in that it responds as expect ed, or, in other terms, it remains calibrated is paramount. The rule‘s frequencies for ensuring that the instrumentation and the system remain appropriate are the minimum we expect to be practical, as
well as workable. Note that we seek verification that the monitoring system continues to perform well; such verification could come from comparisons to a redundant monitoring system (as mentioned by one commenter), from an established program of frequent sensor replacement,
as well as via what the commenters refer to as a ―straight calibration.‖ Of course, should an owner or operator desire to use a different technique, he or she is able to submit an alternative monitoring request to the Administrator in accordance with §63.8(f).

CPMS

– Selection of Monitore d Parameters

Comment 10.1.4.1 1 : Two commenters (0139, 0142) discussed the requirements for continuous monitoring in Table 6 of the proposed rule and stated that many of these parameters are not normal, necessary, or meaningful in assuring the proper opera ting of the air pollution control device. Commenters (0139, 0142) provided reasoning why pH or pressure drop in a packed bed column should not be used for demonstrating compliance. The commenter (0142) added that it is difficult, if not impossible, to esta blish a reasonable set of conditions that would10

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establish the absolute minimum and maximum range of operation during a performance test, given the number of required parameters. The commenter (0142) requested that parameter monitoring for various air pollu tion control devices follow regularly accepted good engineering practices and that Table 6 listed parameters be provided as options and not absolutes. The commenter (0142) presented a detailed discussion about the problems associated with pressure drop, re generation stream flow, and minimum and maximum absorber bed temperature. Another commenter (0153) contended that the rule should allow for alternative combinations or operating parameters that may be more appropriate for new or specific control equipment designs ; f

or example, measuring pressure drop may not be an effective monitoring parameter for low energy scrubbers. The commenter (0153) added that EPA must clarify which of the Table 6 operating limits apply to any given piece of equipment. The commenter (0153) asked if Table 6 was a list to select from or must all the items be in place? Response to comment 10.1.4.1 1 : We disagree with the commenters‘ assertions regarding the usefulness of monitoring parameters. While we agree with the commenters that no t all parameters associated with use of a particular emissions control device or technique can be related directly to an emissions limit , we do not agree that ignoring data associated with the parameters ensures that the control devices or techniques conti nue to operate the way that they did during performance testing that demonstrated compliance with emissions limits. The rule‘s requirements for continuous operating parameter data remain (See Table 7 of subpart HHHHHHH) . As with any monitoring requiremen t, should a source owner or operator choose to use a different parameter than is contained in the rule, he or she is able to submit an alternative monitoring request to the Administrator in accordance with §63.8(f).

Comment 10.1.4.1 2 : One commenter (0139) proposed that continuous VCM emissions monitoring, stack testing for HAPs and work practices to limit iso

- octane emissions from an absorber column are appropriate in lieu of continuous monitoring under the proposed MACT. The commenter (0139) stated that t hey do not believe that §63.11940(c), (d), or (e), should apply
to the VGA. The commented (0139) added that t he continuous VCM monitor should be sufficient for demonstrating compliance with the rule. The commenter (0139) concluded that a work practice stan dard of tracking iso

- octane additions to the VGA recovery device over time should verify usage and eventual loss.10

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Response to comment 10.1.4.1 2 : We disagree with the commenter‘s suggestions. Infrequent emissions or associated parameter evaluations or work practices do not provide the same level of assurance as continuous monitoring, whether emissions or parameter. Th is portion
of th e rule remains unchanged. To the extent adsorbers and acid gas scrubbers or regenerative or

non

- regenerative adsorbers are not used, then the rule‘s monitoring requirements for them are not necessary. Finally, the commenter provided no data to support his contention of equivalency using a work practice standard; should he or she believe this activity is appropriate, he or she
sh ould prepare an alternative monitoring request to the Administrator in accordance with §63.8(f).

Comment 10.1.4.1 3 : One commenter (0121) stated that the term flow indicator is used in various locations in the proposed rule. The commenter (0121) asserted t hat, Table 8 of the proposed rule specifies calibration and accuracy requirements for sources monitoring liquid flow rate or gas flow rate parameters. The commenter (0121) requested that where it is more appropriate, the proposed rule be revised to require flow meters. The commenter (0121) stated
that the proposed rule at 40 CFR 63.11940(a) states, "if flow to a control device could be intermittent, you must install, calibrate, and operate a flow indicator at the inlet or outlet of the
control device to ide ntify periods of no flow." The commenter (0121) requested that the proposed regulation be revised to require flow meters or combinations of flow meters and flow
indicators. The commenter (0121) explained that c ontinuous records of flow to a control device may be utilized in accessing performance and compliance. The commenter (0121) contended that

t his is consistent with other federal requirements. The commenter (0121) referred to 40 CFR 60.107(a)(e). Response to comment 10.1.4.1 3 : We disagree with the comm enter‘s suggestion. While a flow meter could serve as a flow indicator, other types of flow indicators would work equally
well. The rule retains use of flow indicators.

CPMS

- Miscellaneous

Comment 10.1.4.1 4 : One commenter (0139) contended that the requ irement to prepare and submit a CMS Quality Control Program and test plan should be removed. The commenter (0139) stated that i t is overly burdensome to require the preparation and submittal of CMS plans to the agency for approval. The commenter (0139) add ed that e ach regional EPA office is likely10

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to have different interpretations of the requirements and uniformity in enforcing requirements to different companies fostering a non

- competitive atmosphere is important to the industry. The commenter (0139 ) concl uded that d elayed response by the agency leaves the company to guess whether the plan is adequate. Response 10.1.4.1 4 : We find the commenter‘s contention to be misplaced. While §63.11935(b)(1) of the rule requires source owners or operators who use CEMS t o prepare quality control programs and test plans, only performance evaluation test plans are to be submitted to the Administrator for approval. Likewise, while §63.11935(c)(1) of the rule requires source owners or operators who use CPMS to prepare a site

- specific monitoring plans, those plans are only required to be submitted to the Administrator upon specific requests by the Administrator. Rather than being just burdensome, we find that limiting our review and approval to those instances of importance i s an appropriate way to exercise our discretion in managing the program and that plan development provides a tangible means for source owners or operators to discuss, understand, and implement their compliance monitoring strategies. Should source

owners o r operators experience delay or inconsistencies within the Agency, they could develop alternative monitoring requests to the Administrator in accordance with §63.8(f).

Comment 10.1.4.1 5 : One commenter (0144) stated that there are no regulator provisions

p romulgated by EPA for conducting performance evaluation for CPMS. The commenter (0144)
stated that t his could potentially lead to confusion with different facilities having different performance evaluation schemes governing CPMS evaluations. The commenter (0144) suggested that EPA should base the performance of the CPMS on conformance to manufacturer‘s recommendations in terms of ongoing maintenance and calibration. The commenter (0144) added that t hose recommendations could be documented in the site specif ic monitoring plan, which then would be followed by the subject facilities. Response to comment 10.1.4.1 5 : We disagree with the commenter, finding his suggestion to allow use of various manufacturers‘ recommendations would lead to more, not less,
inconsist ency. The rule establishes minimum elements for ongoing quality assurance and control requirements, and the rule leaves specific implementation details to individual source owners or operators, who develop quality control programs that incorporate the min imum elements. We do not intend to relinquish a source owner or operator‘s flexibility to choose how to accomplish specific program minimums.10

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Comment 10.1.4.1 6 : One commenter (0153) expressed concern regarding the impacts associated with the proposed CPM S requirements for temperature, pressure, volumetric flow rate, mass flow rate, and conductivity, including 1) the requirement that monitoring equipment must be capable of measuring the parameter over a range that extends at least 20 percent beyond
the nor mal expected operating range of values for the parameter; (2) the data recording system associated with affected CPMS that must have a resolution that is equal to or better than one

- half of the required system accuracy; and (3) specified calibration freque ncies for parametric monitoring systems. The commenter (0153) referred the EPA to Attachment G of their comment letter, which includes the commenter‘s previous February 4, 2009 comments on the prior proposed CPMS rulemaking which enumerates some of these c oncerns. The commenter (0153) stated they have not been able to evaluate their equipment in light of §63.11935(c)(5), referring to parameters to monitor, ranges, and resolution. The commenter (0153) stated that no cost estimates are included for upgrading equipment. Response to comment 10.1.4.1 6 : We disagree with the commenter‘s concerns over minimum monitoring equipment characteristics and calibration frequencies. In order to ensure that monitoring equipment continues to provide valid data to show that e missions are not exceeded, that equipment needs to be able to accurately measure inputs over the range of expected values and at an appropriate resolution; the rule provides such minimum ranges and resolutions, along with calibration and inspection frequen cies. With respect to Attachment G, in that document the commenter bases his concerns on parametric monitoring associated with another rule (the hazardous waste combustion MACT). Moreover, in Attachment G, the commenter requests annual calibration checks for parameter monitoring, which is what this rule provides except for pH monitors, of which the commenter reports as having 2. Notwithstanding the commenter‘s suggestion to the contrary, average costs for parameter monitoring were
considered and included in cost assessments associated with the rule

. Should parameter monitoring costs pose a problem for owners or operators, they are able to submit alternative monitoring requests to the Administrator in accordance with §63.8(f).

Comment 10.1.4.1 7 : One comme nter (0153) stated he w as not in favor of specified calibration frequencies for parametric monitoring systems, instead, manufacturer‘s recommended frequencies as well as experience in a specific application should dictate the minimum10

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frequency. For example
, the commenter (0153) stated that specifying calibration of pH meters at 8 hours is too frequent for some applications. The commenter (0153) stated additional concerns about what methods will be required to do the calibrations and accuracy determinations. The commenter (0153) added that i t may be that some flow meters can only be calibrated by removal and sending them to a factory or other offsite location. The commenter (0153) provided
additional comments as an attachment which enumerates some of their co ncerns. Response to comment 10.1.4. 17 : While we acknowledge that some manufacturers can provide useful calibration information including recommended frequencies, not all manufacturers supply such information and not all manufacturers provide all elements of a program to ensure minimally acceptable continuing performance of their products. The rule requires these elements to be provide d on a consistent basis. Should source owners or operators remain concerned about these minimum elements, they can submit alternative monitoring requests to the Administrator in accordance with §63.8(f).

Comment 10.1.4. 18 : Two commenters (0142, 0153) stated that the proposed calibration schedule for pH meters (every 8 hours of process operation check the pH or caustic streng th meter‘s calibration on at least two points) is too frequent, unreasonable, and not consistent with manufacturer‘s recommendation, and that pH monitors be calibrated according to manufacturer's specifications or other written procedures that provide adeq uate assurance that the equipment would reasonably be expected to monitor accurately. One commenter (0142) stated that calibration typically involves removing the pH probe from the process and checking the measurement of the device at the process computer or transmitter against a known standard. The

commenter (0142) explained that this activity involves the temporary bypass or disruption of the process control system and potential exposure of personnel to both process and calibration liquids, and requiring that personnel complete this task three times per day, every day, is unnecessary given the known reliability of the device and the potential personal and process safety risks. Response to comment 10.1.4. 18 : We disagree with the commenters‘ suggestions that pH monitors be calibrated only according to manufacturer‘s specifications or other written procedures, in lieu of the simple, consistent approach contained in the rule. While the commenters suggested manufacturer‘s specifications or written procedures, a s well as the known reliability of pH monitors, would provide the assurance of compliance that sources continue to10

- 47

meet emissions limits, the commenters supplied no data to support those claims. Should an owner or operator be concerned about temporary byp ass or disruption of the process control system or potential exposure to workers, he or she could submit an alternative monitoring request to the Administrator in accordance with §63.8(f), to allow installation and use of redundant pH monitors, for direct comparison of redundant monitor outputs should serve as an ongoing calibration check.

Comment 10.1.4. 19 : One commenter (0139) proposed that the backup thermal oxidizer (TO) at their Pedricktown and Henry sites be excluded from the CPMS and recordkeeping

r equirements. The commenter (0139) stated that the back up TO‘s are only operated for a limited number of hours per year for maintenance and repair of the vent gas absorbers (VGA‘s) and the hours allowed for operation of the TO‘s are limited by a federally enforceable Title V permit at each facility. Another commenter (0153) added that if a site qualifies more than the minimum CPMS instruments during the performance test, EPA should allow the secondary devices to be used in case the primary device malfunctio ns ; t hese backup devices should not be subject to deviation reporting, unless they are being operated as primary devices and a malfunction occurs. Response to comment 10.1.4. 19 : We disagree with the commenter‘s suggestion that backup emissions control devi ces be excluded from monitoring and recordkeeping requirements, for the backup emissions control devices are needed to ensure emissions limits are not exceeded at any time . Should a source owner or operator wish to pursue such an exclusion based on site

s pecific operation , he or she should submit an alternative monitoring request to the Administrator in accordance with §63.8(f). The second commenter‘s suggestion is unclear; if the commenter means that a source has two redundant monitors, keeps both monito rs maintained and quality assured, but uses one as a primary and only engages the other (the secondary one) when the primary one malfunctions, we would agree that a properly operated and maintained redundant monitor used only when the primary monitor malfu nctions need not be subject to deviation reporting when it is not used. On the other hand, if the commenter means that a source has two differing types of monitors (one type used as a primary monitor and the other used as a secondary monitor) each of whic h is used to assess compliance independently, then we disagree with the commenter‘s suggestion that data from the secondary monitor be ignored except when the primary monitor malfunctions. As each monitoring system could be used to assess10

- 48

compliance indep endently, one system not showing compliance would be relevant for compliance purposes.

Comment 10.1.4. 20 : One commenter (0153) stated that they have not been able to evaluate the impact of reducing operating data to one

- hour averages and CEMS data to thre e

hour averages within the allotted comment period. Another commenter (0142) contended that EPA should base compliance on daily average parameter values, or as an alternative, if the control device is regulated by another MACT standard, the averaging time specified under that MACT standard. The commenter (0142) provided several examples of the proposed regulatory text where references to ―3

- hour block‖ averages should be replaced with ―daily averages.‖ Response to comment 10.1.4.2 0 : As mentioned earlier, w e disagree with the commenter, since many, if not all, of these sources rely on batch processing that lasts a few hours, not days.
The rule retains 3

- hour block average parameter monitoring, remaining consistent with the 3

- hour averaging period of the exi sting vinyl chloride NESHAP. Should an owner or operator wish to rely on just one averaging period, he or she could submit an alternative monitoring request to the Administrator in accordance with §63.8(f).

Comment 10.1.4.2 1 : Three commenters (0141, 0143 , 0146, 0153) argued that EPA should give preference to recovery devices in lieu of destructive technology. The commenters (0141, 0153) described benefits of recovery devices: return material to the process, minimal HAP and criteria pollutant emissions, an d generation of useful materials. The commenters (0141, 0146, 0153) contended that EPA should not discourage the use of recovery devices by imposing CPMS requirements. The commenters (0141, 0146, 0153) stated the agency previously recognized the benefits o f regulating recovery devices differently from control devices in several existing MACT standards, including the HON and the MON. The commenter s (0141, 0146, 0153) noted that in the MON preamble EPA states ―In the proposal we recognized that the 98%

contro l requirement for all process vents with the affected processes would force incineration, and this might not be appropriate for all process vent streams. Therefore, we also allowed 95% reduction of process vents if ―recovery‖ control technology was employe d to achieve required reductions.‖ [68 FR 63858 (November 10, 2003).] One commenter (0146) contended that compliance options for control and recovery equipment should include concentration, mass, or percentage removal limits, all based on the10

- 49

five best pe rforming facilities. The commenter (0146) stated that emission limits set exclusively on a concentration basis are an unfair measure of performance for some low flow recovery or control devices. Both types of devices can be regulated with a flexible approa ch to allow use of recovery, control, or a combination of technologies. The commenter (0146) added that this approach is consistent with Section 4 of Executive Order 13546, Flexible Approaches, which states: ―Where relevant, feasible, and consistent with r egulatory objectives, and to the extent permitted by law, each agency shall identify and consider regulatory approaches that reduce burdens and maintain flexibility and freedom of choice for the public. These approaches include warnings, appropriate defaul t rules, and disclosure requirements as well as provision of information to the public in a form that is clear and intelligible.‖ The commenter (0146) provided equivalent performance based limits in a table on page 57 of their comments. Response to comment 10.1.4.21 : We disagree with the commenters that EPA should prefer a specific control or recovery device for the PVC rules. The MACT floor emission limits do not specify a particular control or recovery device for achieving compliance. We note that the

ru le referenced by the commenters, the MON, used a different format for the standard, i.e., a percent reduction requirement, which may have allowed such differentiation. We considered setting alternative formats for the process vent emission limits. However, we did not have sufficient information provided from industry on process vent stream flow rates and concentrations to develop or evaluate other formats, such as mass emission rates. The emission limits for process vents apply at the point where the gaseou s stream is released to the atmosphere. Since the rule does not require that affected sources use a specific control or recovery device to meet the process vent limits, a source can use any control or recovery device to meet the final standards. However, E PA must ensure that whatever control or recovery devices are used demonstrate continuous compliance. Therefore, we are requiring continuous parametric monitoring of control device parameters.

10.1.5 Stack Testing

Comment 10.1.5.1 : One commenter (0142) argued that the PVC MACT should allow for a design evaluation to be used in lieu of a performance test to demonstrate compliance with the control requirements for control devices used on small control devices. The commented (0142)
that t his would be consistent wi th other part 63 NESHAPS. For example, the MON allows the10

- 50

use of a design evaluation or performance test for small control devices as well as control devices controlling emissions from storage tanks. The commenter (0142) provided language from §63.2450(h). The commenter (0142) suggested adding language to allow the use of a design evaluation in lieu of performance testing to the PVC MACT rule by adding the appropriate references to the design evaluation criteria in 40 CFR part 63, subpart SS. Response to c omment 10.1.5.1 : We disagree with the commenter‘s suggestion to allow design evaluations to be used in lieu of performance tests to demonstrate process vent compliance. Actual emissions performance, as opposed to theoretical performance, is needed to

asce rtain how well the process vents are being controlled. The rule‘s requirements for performance testing remain; however, an owner or operator may submit to the Administrator a request to use an alternative test method, as described in §63.7(f), or to waive performance testing, as described in §63.7(h), if t he o wne r or operator believes something other than performance testing will provide compliance assurance.

Comment 10.1.5.2 : One commenter (0153) generally supported the use of Method 26A to measure HCl, but requested clarification of how to demonstrate compliance at the proposed new source standard limit. The commenter (0153) stated the Shintech Addis value measured with an FTIR instrument set the new source limit at 0.085 ppmvd (0.126 ug/dscm). The comme nter (0153) added they do not believe that level of detection can be demonstrated in a new plant using Method 26A, noting the ASME report referenced in this rule (footnote, page 29546) indicates
that + or

– 20% random error will result at true stack HCI co ncentration of 1000 ug/dscm using Method 26A. The commenter (0153) stated there is little chance that Method 26A will be able to accurately measure compliance at that level and if the agency sets any limits at levels below limits of detection of the specif ied methods, EPA must clarify exactly how compliance will be
determined. Response to comment 10.1.5.2 : EPA disagrees that Method 26A is not capable of showing compliance with the new source limit. As stated in Method 26A, the typical method
detection lim it for a sample volume of 1 dscm would be approximately 0.04 ppm. The final new
source emission limit s for HCl are 0.17 ppm v for PVC

- only process vents and 1.4 ppmv for PVC

– combined process vents

.10

- 51

Comment 10.1.5.3 : Two commenters (0146, 0153) argued tha t the stack test methods should be expanded to allow those methods to be used to generate the CAA section 114 request test data. Commenters (0146, 0153) pointed out that EPA comingled the top five facility data
from both Method 320 FTIR and Method 0031 sum ma canister methods, and thus (0153) additional methods should be allowed without prior approval as long as the results are valid. Commenters (0146, 0153) added that Method 18 is specified for measuring compliance and (0153) has typically higher detection levels. A commenter (0153) added that the limit of detection in Method 18 for vinyl chloride is 0.2 ppm, and any emission limit should not be set
less than 3 times the non

- detect level, or 0.6 ppm vinyl chloride. Commenters (0146, 0153) noted
that addition al circumstances may warrant the use of a different approved test method, (0146) such as a new plant needing to achieve lower limits of detection. A commenter (0146) concluded that since numerous methods were used to set emission limits, a site should be a ble to use any one of the approved methods without the need to seek alternative approval. Response to comment 10.1.5.3 : We disagree with the commenters. Some of the methods
, such as Method 0031, allowed during the information collection period allow the testers and laboratories flexibility in the procedures and MQOs/DQOs. In order to use th e s e methodologies for compliance, these procedures, MQOs and DQOs must be prescribed. We feel that source

owner s or operators wishing to use methods other than those contained in the rule should submit a site specific request according to the procedures given in § 63.7.

Comment 10.1.5.4 : One commenter (0142) argued that EPA should revise the proposed
concentration

- based limits for vinyl chloride from both existing an d new sources because Method 18 cannot achieve detection limits and quantification limits low enough to match the proposed emission limits. Sections 63.11494(d) and (f) of EPA‘s proposed rule require that EPA Method 18 be used to demonstrate compliance wit h the vinyl chloride requirements. The

commenter (0142) contended that this is not appropriate, because Method 18 cannot achieve detection limits and quantification limits low enough to match the proposed emission limits for vinyl chloride from existing so urces. The commenter (0142) pointed out that EPA Method 18
utilizes tubes , bags, or on

- line sample collection and analysis by gas chromatography/flame ionization detection, and that although tube collection methodology provides the lowest detection limits, vinyl chloride has volatility and recovery issues when collected on a tube, limiting the options to either on

- line or bag sample collection. The commenter (0142) stated that these10

- 52

methods also present difficulties due to the limitations of the GC FID, so that the achievable detection limits and quantification limits are not low enough to match EPA‘s proposed emission standards for vinyl chloride. The commenter (0142) stated the emission standard for new sources is 100 times more stringent, but EPA has cho sen the same analytical method. The commenter (0142) concluded by stating that EPA should revise the proposed concentration based limits for vinyl chloride from both existing and new source because Method 18 cannot achieve detection limits and quantificati on limits low enough to match the proposed emission limits. Response to comment 10.1.5.4 : EPA disagrees with the commenters. Method 18 is not limited to any specific detector technology. Other detector technologies such as mass spectroscopy ( MS ) or ECD m ay be pa i red with gas chromatography, which would allow for lower detection levels for vinyl chloride compared to a flam e ionization detector (FID) . Source owners or operator s may also request alternative methods per § 63.7.

Comment 10.1.5.5 : Two commente rs (0142, 0143) contended that EPA should not require annual performance testing. Four commenters (0141, 0142, 0143, 0146) referred to the Boiler MACT rule that requires testing less frequently than annually. One commenter (0141)
stated the annual stack te sting requirement is unreasonable and more burdensome than stack testing requirements in other MACT and NSPS rules and state performance testing requirements. One commenter (0142) argued that requirements to test process vent emission control devices

annua lly to determine compliance with the concentration limits for vinyl chloride, total organic HAP, and dioxins/furans in proposed §63.11925(e)(4)(i) exceeds the requirements outlined in other MACT rules and is far beyond what is necessary to confirm complian ce. Two commenters (0142, 0146) argued that the proposed rule requires unreasonable and

cost

- prohibitive annual testing for CDD/CDF in order to demonstrate compliance. A commenter (0146) argued that for D/F, the testing requirement for PVC sources should be limited to an initial test demonstrating compliance with the limit, with no additional testing, provided the unit‘s design is not modified in a manner inconsistent with good combustion practices. One commenter (0142) stated that EPA should rely on the p roposed emission limits combined with work practice requirements to minimize the emissions of dioxins/furans. One commenter (0146) argued that EPA should provide PVC sources with the same degree of flexibility for well

- performing sources with respect to TO H/THC, considering that (0142) the performance of air pollution control equipment does not significantly vary from year10

- 53

to year if it is maintained and operated properly. The commenter (0142) also noted that continuous parameter monitoring is required by t he rule and assures emission limits are met. Another commenter (0146) added that many MACT standards and NSPS require one initial performance test (e.g., pulp and paper MACT standards under subparts S and MM), and thus these flexible testing strategies for well

- performing sources, coupled with work practices to
conduct annual burner tune

- ups and to continuously measure oxygen to assure complete combustion, are reasonably appropriate and fully within EPA‘s discretionary authority. Another commenter (0142) co ncluded by stating annual emission testing, especially to the extent required by this rule, is costly and is not value added, and thus the frequency of stack testing should be reduced to once every five years. Response to comment 10.1.5.5 : We agree with th e commenters that annual testing is not necessary to ensure compliance with process vent limits at PVC facilities if continuous parametric monitoring is required. The final standards provide sources the option to comply with continuous parametric monitorin g requirements or use CEMS. In the final rule we have revised the frequency for conducting performance testing to every five years.

Comment 10.1.5.6 : One commenter (0142) suggested the following replacement text for §63.11925(e)(4)(i): ― Initial performan ce testing of air pollution control (APC) devices should be required to establish operating parameter levels. You are not required to conduct a performance test for an emission point for which a performance test was conducted using the same test
methods an d for which either no deliberate process changes have been made since the test, or the owner or operator can demonstrate that the results of the performance test, with or without adjustments, reliably demonstrate compliance despite process changes. ‖ Respo nse 10.1.5.6 : Because we are not requiring annual performance testing, the comments are no longer relevant.

Comment 10.1.5.7 : Three commenters (0143, 0146, 0153) contended that sources should be able to demonstrate compliance with the TOH limit or the THC limit, similar to the approach used for Portland Cement. Commenters (0143, 0153) acknowledged TOH compliance would require additional methods; noting the methods used would be (0143, 0146) the same, or (0153) similar to, the ones used to gather the CAA se ction 114 request data. Commenters (0143, 0146, 0153) acknowledged that there are advantages to Method 25A for THC, such as that it is10

- 54

relatively inexpensive to run, has been used in previous New Source Performance Standards, captures a wide variety of org anics, can be measured with a CEMS device, and may be consistent with EPA's current Uniform Standard approach. Commenters (0143, 0146, 0153) noted THC also has significant limitations, including the fact that it is not always specific for organic HAP and c an be affected by methane (natural gas) or other inlet non

- HAP organics (e.g., ethylene). One commenter (0153) stated that if a source demonstrates compliance with the TOH limit, then it is not a deviation even if the THC limit is exceeded. Response 10.1. 5.7 : We reviewed the commenters‘ suggestion to allow compliance to be determined based on either a total organic hazardous air pollutant (TOHAP) limit or THC limit, and the final rule includes compliance provisions for a TOHAP emissions limit as an alterna tive to the THC emissions limit. We agree with commenters that measurements for TOHAP will require additional methods, and we have included use of EPA Method 320 and EPA Method 18
in the rule. We do not share the commenter‘s concern that THC is not specifi c for organic HAP because as discussed in the Preamble section V.C it is an appropriate surrogate for TOHAP. As to the commenter‘s question about which standard to demonstrate compliance with
, the final rule includes compliance alternatives, and the sourc e must select which alternative it intends to meet. That alternative would presumably be documented in the source‘s title V permit.

Comment 10.1.5.8 : Two commenters (0143, 0146) recommended that TOH exclude
dioxin/furan and vinyl chloride , which are co nsidered separately. Response 10.1.5.8 : The commenters are correct that the total organic hazardous air pollutants limit include s both dioxins/furans (D/F) and vinyl chloride . Although we understand the commenters‘ request to exclude these pollutants fr om TOHAP, we do not believe such a step is necessary . With respect to dioxins/furans
, the contribution is orders of magnitude smaller than
the other HAP that it would not affect the TOHAP limit. Indeed, dioxin./furan cannot be detected using the test meth ods available to test for organic HAP. With respect to vinyl chloride, we have provided a total organic HAP alternative compliance limit for the THC limit for process vents.
Because we are unable to determine a non

- vinyl chloride THC limit, it would be in appropriate to

set a non

- vinyl chloride total organic HAP limit as an alternative compliance limit for the THC limit. Our process vent emissions database does not include the individual FIA (flame ionization analyzer) response factors to vinyl chloride us ed for collecting the Method 25A data during the10

- 55

PVC CAA section 114 testing request
, so we would not be able to subtract the vinyl chloride
from the THC emission limit.

Comment 10.1.5.9 : Two commenters (0151, 0153) contended that batch process operation requirements need clarification. One commenter (0151) pointed out that, EPA requires that performance testing must be done at the ―absolute worst

- case conditions or hypothetical

worst

- case conditions‖ [§63.11945(b) and (c)], yet EPA offers no specific exam ple of how to ascertain that scenario. Another commenter (0153) noted that, as indicated in §63.11945(a), PVC plants operate with batch reactors and continuous strippers, so they would seem to be classified as a combination of batch and continuous operatio ns. They ( 0153 ) argued that as long as the test is designed to incorporate the maximum load to the thermal oxidizer, other batch process considerations of hypothetical or actual worst case conditions should not be relevant. The commenter (0151) requested E PA provide specific examples to assist the regulated community in how the operating conditions should be established for the regulated HAPs. Response 10.1.5.9 : We believe that ―absolute worst

- case conditions and hypothetical worst case conditions‖ are adeq uately explained by the requirements at 63.11945(c). Sources should work with their delegated authority to resolve any case by case particulars. Sources also have the option of testing over a range of conditions to provide operational flexibility, or can chose to monitor the emissions using CEMs

.

Comment 10.1.5.10 : One commenter (0153) argued that EPA must amend §63.11945(d) to remove the requirement to measure organic HAP at the control device inlet, unless a percent

removal option is incorporated in th e rule (a flexible and recommended approach). The commenter (0153) added that subsection (d) (regarding emission profile) is confusing and must be clarified because it addresses total organic HAP at both the control device inlet and outlet. According to th e current proposed rule, only THC is needed at the outlet. Response 10.1.5.10 : The commenter has misinterpreted the proposed rule. The proposed rule citation did not require measurement of organic HAP at the control device inlet. The final
rule also does not require measurement of organic HAP at the control device inlet. The final rule does require an emissions profile be established at the control device inlet ; h owever, the emissions profile may be based on engineering assessment or measurements.10

- 56

10.2 Emission Limits, Operating Limits, and Work Practice Standards

Comment 10.2. 1 : One commenter (0157) argued that EPA should revise the process vent limit from all types of processes to be controlled to 12 ppm total HAP, consistent with the PVC MACT Table 1. They ( 0157) argued that the change in language from ―vinyl chloride‖ to ―HAP‖ in the §61.65(b)(3) requirements adopted to the proposed rule constitutes a 10 ppm HAP limit that lacks justification, and thus the limit should be revised to 12 ppm total HAP. Respon se to comment 10.2. 1 : We are not able to determine what the commenter is referring to in their comment . At proposal
, the total organic HAP limit for existing sources was calculated to be 12 ppmv and the vinyl chloride limit was determined to be 0.32 ppmv. For the
final rule w e have revised the MAC T floor limits and developed two subcategories for process

vents based on additional data received after proposal . Our discussion of the revised MACT floor analysis and results is contained in section V.E of the p reamble to the final PVC rules. If the commenter is referring to the other emission source category when emissions are routed through a closed vent system to a control device, those sources must comply with the outlet emission limit from the process vent c ontrol device. In the final rule, process vents include batch process vents, continuous process vents and miscellaneous process vents. Miscellaneous vent means gaseous emissions from samples, loading and unloading lines, slip gauges, process wastewater

tre atment systems and pressure relief devices that are routed through a closed vent system to a control device and that are not equipment leaks.

Comment 10.2. 2 : One commenter (0142) argued that samples themselves are not emission points and therefore cannot be process vents. The commenter (0142) stated that b ased on the proposed rule, EPA is requiring that ―samples‖ (as process vents) be connected to a closed vent system and control device. The commenter (0142) stated that t his is impractical because samples are collected into containers. The commenter (0142) added that l arger containers (i.e. drums, pails, or totes) are exempt from the definition of batch process vent. Since sample containers are typically much smaller than drums, pails, or totes, one would i nfer that sample containers should also be exempt from the definition of a process vent. The commenter (0142)
concluded that i f EPA intended that the process vent provisions apply to sample systems (rather than ―samples‖), these requirements are covered un der 40 CFR 63.1032 of subpart UU as10

- 57

referenced in the equipment leak provisions of the proposed rule and are also exempt from the definition of batch process vent. Response to comment 10.2. 2 : W hile w e agree that samples are not process vents, the part
61 rule required that samples be returned to the process and emissions controlled to meet 10 ppmv of vinyl chloride. T he final rule, we include samples as ―miscellaneous vents‖ and require that emissions from ―miscellaneous vents‖ be controlled to meet the ap plicable process vent
emission limit.

Comment 10.2. 3 : One commenter (0153) stated that EPA must clarify whether the HCl limit requires measurement of HCl only, or whether it is meant to include hydrochloric acid and chlorine as measured separately by Meth od 26A. Some of the other MACT standards (e.g., Hazardous Waste MACT), require HCl results to be reported as total chloride equivalents. On the other hand, the commenter (0153) stated that the Portland MACT requires control of HCl only, since it is a reaso nable indicator that any low levels of other acid gases are removed by the
scrubbers. Response to comment 10.2. 3 : In the final rule we have determined that HCl is an appropriate surrogate for chlorine. Therefore, Method 26A must be used to demonstrate

com pliance with the HCl emission limit but only the HCl emissions have to be reported.

Comment 10.2. 4 : One commenter (0142) argued that EPA should require oxygen correction in the stack to 7% rather than to 3% as proposed. The commenter (0142) pointed out
that Table 1 Emission Limitation for Process Vents establishes a limitation for hydrogen chloride for new sources to be 0.17 ppmv. Additionally, note (b) indicates the measured emission limits
are to be corrected to 3% O 2 . The commenter (0142) stated that t he 0.17 ppmv level for a wet stack can be outside the capability of the required method (Method 26 or 26A). The commenter (0142) added that a nother point of concern is the requirement to correct and report the value to
3% O 2 . The commenter (0142) stated that t hese facilities typically operate at O 2 levels between
6% and 10%. The commenter (0142) added that t his O 2 level is typically due to the process vent
load ; t he higher O 2 content provides improved operational reliability while feeding vents. The

comme nter (0142) stated that c orrecting to 3% O 2 also does not compare with other standards dealing with the same compound (subpart EEE). The commenter (0142) suggested that t he correction should be changed to 7% to allow consistent representation with subpart EEE. In10

- 58

addition, the hydrogen chloride standard for new sources is set at 7%. The commenter (0142)
added that t he chlorine/hydrogen chloride standard under 40 CFR part 63 subpart EEE for hydrochloric acid furnaces for new sources has the level at 7% O 2 (§ 63.1218 (a)(6)). The commenter (0142) recommended that the hydrogen chloride standard in Table 1 (29534) be consistent with 40 CFR §63.1218 and that the O 2 correction standard be 7% O 2 Response to comment 10.2. 4 : We disagree with the commenter‘s suggestion to change the oxygen correction from 3 to 7 percent in this rule . As the actual oxygen percent content from a specific source can vary, it is important to select, and then use, a consistent basis for comparison. The testing data that were used to calcula te the emission limits were all based on an oxygen correction of 3 percent as required by the PVC CAA section 114 testing requirement. Emissions limits established in the rule were corrected on a consistent basis to 3 percent oxygen,
and the rule retains that 3 percent oxygen correction. In addition, the commenter provided no data to support his claim that Method 26 or 26A may be unsuitable in certain circumstances for use by the rule. The final hydrogen chloride emissions limits for new and existing sou rces, are within detection limits for Method 26 and Method 26A.

10.3 MACT Floor

Comment 10.3. 1 : One commenter (0146) agreed with EPA that both thermal oxidizers with acid gas scrubbers and chemical absorbers are effective technologies for controlling organic
H APs, including VCM. Response to comment 10.3. 1 : We thank the commenter for their comment

.

Comment 10.3. 2 : Tw o commenter s ( 0146, 0153) contended that EPA should set the THC limit and compliance demonstration based on non

- methane hydrocarbons to ensure meth ane spikes will not impact compliance demonstrations. EPA set the THC limit based on total hydrocarbons, including methane. However, this method could result in non

- compliance in the event of a natural gas spike, particularly during a cold start

- up. PVC fa cilities submitted non

methane data to EPA pursuant to the CAA 114 request and EPA should use that data to reset the
THC limits. Response to comment 10.3. 2 : We disagree with the commenters‘ suggestion to exclude methane from the total hydrocarbon (THC) emi ssions limit. As mentioned earlier with respect to11

- 59

the TOHAP emissions limit, we do not believe the contribution or costs associated with obtaining extra data warrant excluding methane from the THC emissions limit. Moreover, w e find the commenters‘ conce rn regarding methane spikes during start

- ups to be moot, since THC emissions testing will not occur during startup periods. Finally, we got neither sufficient non

methane data submitted by facilities to calculate emission limits , nor sufficient THC speciat ion data from each facility in order to determine a non

- methane THC emissions limit

. As a result, the
final rule maintains a THC, not a non

- methane THC, limit

.



### 11.0 RESIN

Comment 11.1 : One c ommenter ( 0139 ) argued that data from the Henry, Illinois source
shou ld be included in setting the dispersion MACT floor limit. As a part of i t s comments, t he commenter (0139) removed non

- detected analytes known not to be in the process, making the data comparable, and thus argued that these data should be considered within the dispersion floor
limit data set. Response to comment 11.1 : For the final rule, we have evaluated the additional and revised data submitted by the Vinyl Institute and PolyOne and have included the appropriate data from the PolyOne facilities into the respective data sets for both dispersion and suspension blending resins. See also section V.E.2 of the preamble for the final rule.

Comment 11. 2 : One commenter (0146) argued that material substitution is not a viable

non

- technological factor for setting floors for resin stripping. Response to comment 11. 2 : In the final rules, we are not requiring material substitution as a control technology to meet the emission limits, though sources may choose to comply through material substitution at their discretion.

Comment 11. 3 : One commenter (0118) supported using data collected using EPA Method 107 to set the MACT floors rather than Method 8260B. The commenter (0118) stated that a benefit of using a larger data set containing individual strippers and reactors f or stripper samples is related to startup and shutdown. The commenter (0118) stated that it is possible that when either starting up or shutting down a daily composite could be comprised of only a single sample. The commenter (0118) contended that data sho w a limit based solely on daily12

- 60

composites would underestimate the true variance associated with individual samples. The commenter (0118) concluded that this underestimation would lead to a limit that may be unattainable during startup and shutdown events. Response to comment 11

. 3 : We have revised our MACT floor variability analysis based on data submitted by the industry after the rule proposal to incorporate the larger dataset using results from EPA Method 107 testing. See section V.E. 2 of the preamble t o the final rules where we discuss the data sets used to develop the final stripped resin limits.



### 12.0 STORAGE VESSELS

Comment 12.1 : One commenter (0011) addressed EPA‘s conclusion that because PVC manufacturers all fall below established regulations for sto rage vessels, this will be the standard for PVC manufacturers. The commenter (0011) contended that this stance essentially exempts PVC manufacturers from the kinds of protections for storage facilities that deal with sealing mechanisms, floating roofs, and routing streams to a controlled device that could reduce volatile organic emissions by 95 percent. Response to comment 12.1: We disagree with the commenter. In addition to a MACT floor analysis for storage vessels, we evaluated a beyond the floor option o f complying with storage vessel requirements equivalent to existing storage vessel regulations, primarily subpart Kb. Based on this evaluation, we determined it was appropriate to require control and compliance of storage vessels meeting the subpart Kb siz e and vapor pressure thresholds. However, meeting more stringent control levels was not cost

- effective. Data that were collected for development of the PVC standards shows that this source category does not use storage vessels above the vapor pressure and size thresholds of the final rule. We are requiring that all other storage vessels meet the operating, inspection and maintenance requirements for fixed roof vessels or comply with either the controlled fixed roof or floating roof requirements as discussed in the preamble to the final PVC rules.

Comment 12.2 : One commenter (0142) argued that recordkeeping on degassing and cleaning events should not be necessary if work practices are in place. The commenter (0142) contended that degassing and cleaning opera tions occur on a routine and non

- routine basis, and12

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thus maintaining a record of all of these activities would present an unreasonable burden. Therefore, t he commenter (0142) proposed that EPA delete requirements for recordkeeping and
emissions estimations on every degassing and cleaning event, and instead control emissions during these events with work practice requirements. Response to comment 12.2 : We agree with the commenter regarding the proposed recordkeeping requirements for degassing. We have remove d this requirement from the final
rule.

Comment 12.3 : Two commenters (0157, 0134) expressed concern with EPA‘s classification of a ―leak‖ from a pressure vessel closure device as a violation of the rule. They requested clarification why leaks from this so urce were singled out in contrast to leaks from other devices, and argued that instead all leaks should be subject to the same leak detection and repair (LDAR) requirements. One commenter (0134) contended that the Court previously held, regarding leaks of vinyl chloride from equipment, ―...fugitive, or unintended releases of VC will occur. Such episodic, pre

- exhaust

- phase discharges are not illegal provided that certain work

practice standards are complied with to minimize such occurrences.‖[U.S. v. Conoco, N o. 83

- 2518 (W.D. La. June 1, 1984)], and thus the use of area monitoring systems for vinyl chloride and subsequent application of LDAR procedures constitute acceptable work

- practice standards.
One commenter (0134) argued that the agency should modify §63.1 1910(c)(3) and (4) and remove the special reporting requirement understanding that minor releases are not deviations of the operation. Response to comment 12.3: We disagree with the commenters regarding EPA‘s classification of a leak from a pressure vessel as a violation of the rule. A pressure vessel is defined as ―a vessel that is used to store liquids or gases and is designed not to vent to the atmosphere as a result of compression of the vapor headspace in the pressure vessel during filling of the press ure vessel to its design capacity.‖ Since pressure vessels are defined to not vent to the atmosphere, this inherently makes them different from other storage vessels, such as fixed roof storage vessels that are designed to vent with diurnal temperature cha nges. We believe that because pressure vessels are designed to not vent to the atmosphere and with no detectable emissions, a leak (i.e., above 500 ppm background) from one would be inconsistent with the definition of a pressure vessel, and hence a violati on of the rule.12

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Comment 12.4 : Two commenters (0153, 0142) argued against the prohibition of all detectable emissions from pressure vessels in all circumstances. One commenter (0142) argued that it is unreasonable to prevent the adjustment for background c oncentration, and that Section 3.4 of Method 21 includes an adjustment for ambient concentrations of VOCs. This commenter (0142) argued that if background concentrations are not taken into consideration when defining a leak, a source may be considered in v iolation and required to make unnecessary repairs to a pressure vessel in response to a ―leak‖ that does not exist. They (0142) stated that if work practices are to be required for pressure vessels and monitoring of ―leak interfaces‖, EPA should clearly de fine what a ―leak interface‖ means and also should clearly define a reasonable leak threshold that takes background concentrations of VOC/HAP into consideration. Both commenters (0153, 0142) requested clarification of the term ―leak interface.‖ The comment ers (0153, 0142) state that equipment is already regulated under the equipment leak provisions of the rule (i.e. pumps, valves, connectors, etc.), and thus clarification is needed as to what EPA considers a ―leak interface‖. The commenter (0142) recommende d using the previously established ―no detectable emission‖ level of 500 ppm above background for this leak definition. One commenter (0153) argued that leaks are monitored under LDAR program and are not deemed automatic violations, and thus such leaks sho uld not be considered deviations unless specific requirements of the LDAR program have not been followed. They (0153) also argued that the use of the affirmative defense criteria should be an available option. One commenter (0153) disagreed with the propos ed rule‘s inclusion of pressure vessels storing gases, liquids, or gases and liquids as a category of tanks to be regulated. The commenter (0153) argued that other MACT standards provide exemptions for ―Pressure vessels designed to operate in excess of
204 .9 kilopascals and without emissions to the atmosphere‖. The commenter (0153) contended that since these vessels are already regulated by other rules, the current exemption for pressure
vessels in other MACT rules should also be used in this rule. The comm enter (0153) argued that pressure vessels are already regulated by OSHA and EPA‘s Risk Management Mechanical Integrity Program and the ACC Responsible Care Management Systems requiring inspections of VCM storage sphere performed per API standards as well a s company inspection procedures. The commenter requested explanation of the perceived need and required scope of the rule before adding what they argue is a duplicative requirement. One commenter (0146) argued that other MACT standards such as HON, MON, an d OLD have exempted pressure vessels from the definition of storage vessels, and thus they contended that the agency should do likewise for this12

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proposed rule. The commenter (0146) further argued that the requirements for leak interface monitoring on press ure vessels are excessive and provide no definition of leak interface. Thus, the commenter (0146) requested that EPA delete section 63.11910(c)(4) and clarify the required monitoring frequencies if the agency retains section 63.11910(c)(3). The commenter ( 0146) requested EPA rely on the requirements of the proposed section 63.11915 to address equipment leaks from components on storage vessels. At a minimum, the commenter (0146) requested EPA to provide a definition of ―potential leak interfaces‖ or similar guidance as the term is not defined. In addition, he requested that EPA clarify the required monitoring frequencies if the agency retains section 63.11910(c)(3). Response to comment 12.4: We agree with the commenters regarding adjusting for background conc entration when identifying pressure vessels that are leaking and this allowance is provided in the final rule. In the final rule we have defined pressure vessels as vessels that are used to store liquids or gases and are designed not to vent to the atmosph ere as a result of compression of the vapor headspace in the pressure vessel during filling of the pressure vessel to its design capacity. When the vessel is not being filled, it must be operated in such a manner that
there are no detectable emissions whic h means the calculated value should be compared to the performance standard (i.e. 500 ppm above background), not a leak definition. The no detectable emission requirements are described in 40 CFR 63, subpart UU. Therefore, any detectable emissions from a p ressure vessel are a deviation. The term ―leak interface‖ is not defined in this subpart, but is as described in Method 21 at 40 CFR part 60, appendix A

- 7. EPA Method 21 requires that during a leak survey the probe inlet of monitoring instrument must be pl aced at the surface of the component interface where leakage could occur. In Section 8.3 of Method 21, the appropriate interface to be probed for leaks is described for each component type. A potential leak interface is a location where organic vapor leaka ge could occur. Potential leak interfaces that are associated with covers and closure devices include, but are not limited to, the interface of the cover and its foundation mounting; the periphery of any opening on the cover and its
associated closure devi ce; and the sealing seat interface on a spring

- loaded pressure

- relief valve. We disagree with the commenter that pressure vessels should be exempted from this rule. While some other MACT standards exempt pressure vessels from regulation, precedent for

regu lating pressure vessels exists in 40 CFR part 63, subpart DD (National Emission Standards
for Hazardous Air Pollutants from Off

- Site Waste and Recovery Operations). The pressure12

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vessel requirements in the Off

- Site Waste and Recovery Operations rule are con sistent with those we are finalizing in the PVC rule. We disagree with the commenter that section 63.11910(c)(3) should be deleted. We believe that it is appropriate and necessary to monitor leak interfaces on pressure vessels in order to ensure that they are in compliance with the final rule. However, we do agree with the commenter that section 63.11910(c)(4) should be revised, as it is unnecessary to submit a separate report for leaks from pressure vessels. We are instead requiring that a release from a

p ressure vessel be reported in the deviation report.

Comment 12.5 : One commenter (0157) argued that the requirement to install and maintain a fixed roof (including conservation vent) on any storage vessel with a capacity greater than 10,040 gallons withou t regards to the vapor pressure of the HAP stored, is excessive. Instead, the commenter (0157) argued that a total HAP vapor pressure upper limit should be
established before a fixed roof with conservation vent is required; as other MACT standards have

cut

- off limits established that would account for the vapor pressure of the HAP prior to the
installation of controls outside a fixed roof. Response to comment 12.5: We disagree with the commenter that a HAP vapor pressure
limit should be established before a fixed roof with conservation vent is required. Recent court rulings have required EPA to set standards under section 112(d) for all sources of HAP emissions at major source facilities. As we have set more stringent requirements for larger capacity storage vessels with higher HAP vapor pressures (e.g., install floating roof, route emissions to a control device), standards are also required for the smaller capacity storage vessels with lower HAP vapor pressures. We believe that most, if not all, storage vess els with a capacity of at least 10,040 gallons should already have a fixed roof with conservation vent installed; therefore, there should be very little burden associated with the requirement, and we believe it is appropriate in order to meet our obligatio n to set standards for all storage vessels.

Comment 12.6 : One commenter (0153) supported the use of HON storage capacity and vapor pressure cutoffs proposed by the agency, which they believed will facilitate the ultimate integration with the co

- located ED V/VCM/PVC plants and other facilities regulated by the
HON.12

- 65

Response to comment 12.6: We thank the commenter for his support. The storage capacity and vapor pressure cut

- offs are based on 40 CFR part 60 subpart Kb requirements.

Comment 12.7 : One commenter (0153) supported the provision in section 63.11910(a)(2)(ii)(B) allowing for conservation vents for fixed roof tanks, which they believed is necessary for the safe operation of tanks. Response 12.7: We thank the commenter for their support.

Comment 12.8 : One commenter (0153) supported the provision allowing operators of pressure vessels to vary from the annual inspection frequency for valid safety reasons, as specified in section 63.11910(a)(2)(B)(3). Response to comment 12.8: We thank the commenter for t heir support.

Comment 12.9 : Two commenters (0142, 0146) argued that vapor balancing should be an allowed method of control for compliance with storage tanks provisions. They (0142, 0146) contended that because EPA has allowed vapor balancing as a control option for storage tanks in other MACT rules, EPA should also allow for this technology in the proposed PVC MACT rule. Two commenters (0142, 0146) recommended language to be incorporated into the final rule to allow vapor balancing. Response to comment 1 2.9: We agree with the commenters that vapor balancing has been used in other MACT rules. However, we do not have data on the appropriateness of using vapor balancing on storage vessels in this source category. A facility can request the Administrator to

u se vapor balancing as an alternative means of emission limitation under 63.6(g) of the part 63
General Provisions.

Comment 12.10 : One commenter (0142) requested that the PVC MACT allow for design evaluations in lieu of performance testing for storage tank control devices and for small control
devices. The commenter (0142) argued that language should be added to allow the use of a design evaluation in lieu of performance testing, as this would be consistent with other part 63
NESHAP

. Response to comment 12. 10: We agree with the commenter that design evaluations should be allowed for storage tank control devices and have added this option to the final rule.12

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Comment 12.11 : One commenter (0142) supported EPA‘s proposed 95% requirements for closed vent systems going to a control device, stating that it is consistent with subpart Kb requirements for fixed roof tanks sent to a control device. Response to comment 12.11: We thank the commenter for their support.

Comment 12.12 : One commenter (0142) argued that insta llation of closure devices that secure on fixed roof storage tanks and on pressure vessels should not be required. The commenter (0142) agreed that closures on storage tanks and pressure vessels should be maintained in the closed position when access to th e vessel is not needed, but they pointed out that the requirements to install ―closure devices that secure‖ is unreasonable and not required by
other part 63 NESHAP nor NSPS Kb. The commenter (0142) argued that the cost to install
closure devices on fixed roof storage tanks and pressure vessels was not evaluated as part of the MACT floor, and therefore, EPA should remove this requirement from the proposed rule. Response to comment 12.12: We believe that the commenter has misinterpreted the term
―secure‖ to mean that the closure device must have a latch, bolt, or other device to secure it in the closed position; this is not the intention of the language. By using the term ―secure,‖ we mean that if there is a latch, bolt, or other device to secure the closure device in the closed position, it must be secured such that there are no visible cracks, holes, gaps, or other open spaces between the perimeter of the opening and the closure device. Additionally, precedent for using this language exists in 40 CFR part 63 , subpart OO (―National Emission Standards for
Tanks

— Level 1‖), which says in §63.902(b)(3)(i): ―[Each opening in the fixed roof, and any manifold system associated with the fixed roof, shall be] equipped with a closure device designed to operate such that when the closure device is secured in the closed position there are no visible cracks, holes, gaps, or other open spaces in the closure device or between the perimeter of the opening and the closure device.‖

Comment 12.13 : One commenter (0142) requested that EPA include provisions to allow for maintenance down time for control equipment for which storage vessels are vented. Th e commenter (0142) argued that most control equipment requires periodic maintenance and during these times, it is not practical to empty all regulated storage vessels of material. The commenter (0142) pointed out that most part 63 NESHAP have provisions to allow 240 hours of12

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maintenance downtime, during which the emission limits specified in the rule would not have to
be met. The comm enter (0142) requested that EPA include similar provisions in the PVC
MACT. Response to comment 12.13: We agree with the commenter that an allotment of 240 hours should be provided for maintenance down time for control equipment to which storage vessel ar e vented because the emissions generated from a storage vessel cannot be ―shutdown‖ to
conduct control device maintenance, unless the tank is emptied and degassed. E mptying and degassing the tank can create more emissions than idling the tank while making the control device repairs. For these reasons, we have allowed this in other NESHAP standards (e.g., 40 CFR part 63, subpart G). We have added this provision to the final rule.

Comment 12.14 : One commenter (0142) requested clarification on the storage ves sel requirements, asking that it be clearly stated that these requirements only apply to storage vessels in Hazardous Air Pollutant (HAP) service and not to storage vessels containing non

- HAP materials. The commenter (0142) argued that since the pollutants of concern for this regulation are the HAP constituents, EPA should clarify that the only regulated storage vessels at the
affected source are those in HAP service. Response to comment 12.14: We agree with the commenter and have clarified in the final
rul e that the storage vessel provisions only apply to vessels in HAP service. The PVC MACT standards generally are applicable to sources that emit HAP or are in HAP service.

Comment 12.15 : One commenter (0142) argued that the current fixed roof tank inspecti on and repair requirements are inconsistent with other part 63 NESHAP and should be deleted from this proposed rule. The commenter (0142) also contended that there was no basis for EPA choosing the 5 day repair requirement, and that the 45 day repair requi rement is based on floating roof tank requirements in 40 CFR 63.1063(e) of subpart WW rather than fixed roof requirements. The commenter (0142) argued that requirements for floating roof tanks should not be applied to fixed roof tanks. Response to comment 12.15: We agree with the commenter that the 5 day repair requirement is not appropriate, and it has been removed from the final rule. However, we disagree with the commenter that the 45 day repair requirement is not appropriate. We believe13

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that both floati ng roof and fixed roof tanks should be placed on the same repair schedule and that 45 days is an appropriate period of time to ensure that the leaking tanks are repaired.



### 13.0 WASTEWATER

13.1 Compliance and Monitoring

13.1.1 Relaxed testing for wastewater streams

Commen t 13.1.1.1 : One commenter (0134) proposed that language be added to 40 CFR 63.11975(d) and (e) indicating that if three consecutive monthly samples show levels of VCM or
total HAP below 30% of the threshold then follow

- up sampling be required once every th ree years. Another commenter (0153) proposed that streams found to be stable with less than 1,000 mg/l of HAP should not have to be re

- sampled each month. Three commenters (0142, 0144, 0146) said monthly sampling would be costly, time

- consuming, and place an unnecessary burden on both affected sources and the regulators. One commenter (0144) argues that sampling frequency should be reduced because a well designed test plan can capture the variety of facilities product formulations and sample the worst case wastewater. One commenter (0157) suggested that monthly sampling be extended to quarterly. Another commenter (0146) suggested that vinyl chloride and total organic HAP sampling frequency should be no more than once every five (5) years. An initial demonstr ation of total organic HAP at streams that need treatment is justified because organic HAP is not regulated under the current vinyl chloride NESHAP. A commenter (0134) also requested that EPA add language to 40 CFR 63.11975(e)(2) to
allow low flow rate str eams, less than 10 liters per minute, to permanently abstain from both total HAPs sampling and re

- establishment of flow rates absent a process change. Stream flow rates are fixed by design and have little variation. Two commenters (0146, 0153) supported t he link to HON wastewater requirements: The 1,000 ppm total HAP cutoff is already in use in plants that are regulated by the HON. 40 CFR 63.11965(a) requires an initial determination based on the Table 9 of the HON (subpart G). Table 9 of the HON has many analytes (74 in all), most of which will NOT be present in PVC plant wastewater.13

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The proposed MACT rule uses the HAP list from the Table 9 of the HON (subpart G) except for formaldehyde. One commenter (0146) recommends that formaldehyde be
added to the P VC process HAP list to be analyzed as part of total organic HAP for both stripped resin and wastewater, as it was detected and reported by several PVCPUs during
the section 114 30

- day testing that took place in late 2009, and early 2010. Commenter (0146) provided the following language suggestion for §63.11980(b), footnote for variable ―Ci‖: ―Concentration of each individually identified HAP, in ppmw, where a value of zero should be used for any HAP concentration that is below the detection limit.‖ This

re vision is necessary, because Table 9 does not include formaldehyde, and because many PVC process specific HAPs, included in Table 9, may not be present in wastewater. One commenter (0134) argued wastewater stripper outlet concentration limits are not

appro priate, but work practice standards will effectively minimize HAP emissions. The commenter also proposed that EPA allow for a reduced sampling frequency for low flow and/or
low concentration wastewater streams. Response to comment 13.1.1.1 : With respect to the comments related to the HON requirements and the sampling frequencies, we have removed the HON

- related requirements from the final rule and revised the limits and requirements for process wastewater. We agree
with the commenter that an initial determi nation for streams that require treatment is necessary. We also recognize that stream flow rates are fixed by design and have little variation. Therefore, for streams that do not require treatment, follow

- up performance testing is required at least
annuall y. However, monthly sampling and analysis for streams that require treatment is necessary to maintain continuous compliance with the process wastewater limits. We disagree that low flow rate streams, less than 10 liters per minute, should permanently absta in from sampling. While we have removed the requirement to establish flow rate for the purposes of compliance, if it is demonstrated that a stream is below the limits for process wastewater, regardless of flow rate, then that stream does not require treat ment and must be resampled annually.
For the final rule , we calculated MACT limits for total non

- vinyl chloride organic HAP and vinyl chloride separately. Based on our evaluation of the total non

- vinyl chloride organic HAP limits, we determined that the 1, 000 ppmw threshold for total organic HAP, above which facilities would have been required to comply with the HON wastewater provisions, was not appropriate for the final rule as all streams must meet a limit for total non

- vinyl chloride organic13

- 70

HAP that is much lower than the proposed 1,000 ppmw threshold. See section V.E.2 of the preamble to the final rules for additional discussion. We have revised Equation 1 in section 63.11980(b) to clarify that a value of zero should be used for any HAP concentration t hat is below the detection limit. We have also limited the specific HAP that must be analyzed in process wastewater samples to a subset of HAP listed in Table 10 to the final rule. The Table 10 HAP are the same for both stripped resin and process

wastewate r, and represent those HAP which data indicate are, or may be, present in process

wastewater streams from the PVC industry . See the related discussion and rationale for stripped resins. Table 10 includes formaldehyde which is not included in Table 9 of the HON. We disagree with the commenter‘s assertions that wastewater stripper outlet concentration limits are not appropriate and that work practice standards will effectively minimize HAP emissions. No data were provided to support the claim that outlet str ipper limits are not effective or appropriate.

Comment 13.1.1.2 : Four commenters (0142, 0146, 0153, 0157) argued that wastewater streams can vary depending on process condition and any grab sample represents only a point in time. The commenters (0142, 014 6, 0153, 0157) stated that there are no averaging provisions for concentration, which is unlike other CAA wastewater

- related requirements which have annual average concentration determination provisions (see HON §§63.132(c) and 63.144(b), and BWON §61.355( c)). In addition, the commenter s (0142, 0146, 0153, 0157) stated that there is no annual average flow rate for determining if streams must be controlled. The commenters (0142, 0146, 0153, 0157) suggested that the PVC MACT should have the same threshold of 10 l/min as allowed for the HON Table 9 total organic HAP determination and allow an annual average
concentration. Response to comment 13.1.1.2 : We have removed the HON

- related requirements for process wastewater in the final rule. See previous responses to comments and associated sections of the preamble to the final rule for more details. In the final rule, wastewater samples must be taken once per month to demonstrate compliance with the total non

- vinyl chloride organic HAP
wastewater emission limit.

C omment 13.1.1.3 : Two commenters (0146, 0157) argued that wastewater stream variability presents a challenge to facilities that are required to construct new WW strippers or13

- 71

other control devices to comply with new limits. The commenters (0146, 0157) conten ded that PVCPUs should be allowed to gather WW stripper VC data for the year prior to the initial demonstration of compliance so that the first month of continuous compliance can be calculated as a 12 month rolling average as set forth in section 63.11975( a)(3)(iii). Response to comment 13.1.1.3 : We have removed the 12

- month rolling averaging provision from the final rule requirements for wastewater. Continuous compliance with the process wastewater limits must be met on a monthly basis as the revised MACT floor variability analysis was conducted for monthly compliance.

13.1.2 Point of determination (POD) / Intermittent wastewater

Comment 13.1.2.1 : One commenter (0146) asked that EPA remove the word  ̳directly‘ in any wastewater language. The commenter (0146) sta ted that i n section 63.11965(b)(1), the statement ―Route wastewater streams through hard piping from the point of generation directly to the treatment process....‖ includes the word  ̳directly,‘ which could be misinterpreted to
exclude intermediate vessels su ch as a wastewater stripped feed tank. The commenter (0146)
added that i n accordance to the part 61 NESHAP, wastewater collection systems that have a vinyl chloride concentration greater than 10 ppm can include collection vessels such that wastewater may n ot go  ̳directly‘ to the treatment process, and such intermediate vessels are either pressure vessels or are vented to the closed vent system. Response to comment 13.1.2.1 : We agree with the commenter that the final rule requirements need to be clarified to avoid confusion and unintended application of the standards. The word ―directly‖ and related language have been removed from the final rule requirements for process wastewater.

13.1.3 Rule Clarifications Requested

Comment 13.1.3.1 : Three commenters (0144, 0146 , 0153) requested a provision for calculating total organic HAP when the concentration of an individual pollutant, using approved methods of analysis, is non

- detect. Is it appropriate to use zero for non

- detects in the summation?13

- 72

Response to comment 13.1. 3.1 : In the final rule, we have clarified that for the calculation
of total non

- vinyl chloride organic HAP, any result for an individual HAP that is below the detection limit, or a non

- detect, is to be assigned a value of zero.

Comment 13.1.3.2 : One comme nter (0153) requested that EPA explain why biological wastewater treatment equipment is being incorporated into the PVCPU because no explanation is currently provided in the preamble or is known to the industry. Response to comment 13.1.3.2 : The final rul e contains no specific requirement for sources to use biological treatment.

Comment 13.1.3.3 : One commenter (0134) asserted that in 40 CFR 63.11975(e)(3) ―vinyl chloride‖ was mistakenly used in the place of ―total HAP.‖ Response to comment 13.1.3. 3 : We a gree with the commenter. Section 63.11975 has
been revised in the final rule.

Comment 13.1.3. 4 : One commenter (0157) argued that the total HAP control requirements (testing, sampling, etc.) should be removed from the wastewater rule because in the preambl e, Section "V. Impacts of the Proposed PVC Rule," the value of total HAP removed is equal to the reduction in VC, 0.4 tpy. Therefore, the commenter (0157) concluded, the total HAP control requirements result in no reduction in VC. Response to comment 13.1. 3. 4 : We disagree with the commenter regarding the proposed rule. At proposal, we included a total HAP limit, and because vinyl chloride is a HAP, it was
included in determination of the total HAP limit. In the final rule we have revised the MACT
floor limi ts for process wastewater to specify concentration limits for total non

- vinyl chloride organic HAP and vinyl chloride separately. The changes are discussed in section V.E.2 of the preamble to the final rules.

Comment 13.1.3. 5 : Two commenters (0142, 0146) recommended that the language of 40 CFR 63.11975(e)(3) be changed. The commenters (0142, 0146) added that t he proposed rule requires that if monthly performance tests show total HAP greater than or equal to 1,000 ppm (by weight) and the annual average flow rate is greater than or equal to 10 liters per minute, then you must use a treatment process to reduce the vinyl chloride as specified in 40 CFR 63.11965(c)13

- 73

and you must demonstrate compliance as specified in 40 CFR 63.11975(b). The commenter (0142, 0146) added that t he beginning of section 63.11975(e)(3) addresses the concentration of total HAP. However, the commenters (0142, 0146) added that treatment process focuses on reducing the vinyl chloride concentration. The commenters (0142, 0146) propose d chang ing the language to ―then you must use a treatment process to reduce the total HAP concentration as specified in....‖ One commenter (0146) requested clarification of 40 CFR 63.11965(d). Under section 63.11965(d)(1), the total annual wastewater volume of all streams within the PVCPU must be under 1.4 million gallons over a designated 12

- month period and have a total annual HAP concentration under 1,000 ppmw in order to be exempt from control and treatment requirements. The commenter (0146) explained that i f, f or example, within a 12

- month period, a PVCPU generated a 1,500 ppm HAP in

- process wastewater stream that flowed at 100 l/min for 60 min, the stream would not be subject to control and treatment since the annual average flow rate is less than 1,600 gal/yr, which is less than 1.4M gal/yr. The commenter (0146) added that t his exercise would be repeated for other wastewater streams that are generated or are anticipated to be generated over a year, and then totaled for the Unit. The commenter (0146) concluded t hat a s long as the unit has generated less than 1.4 M gallons of low flow rate streams in a year, these low flow rate streams do not require control and treatment. Response to comment 13.1.3. 5 : In the final rule, we determined the MACT floor level of

contr ol for wastewater to include concentration limits for total non

- vinyl chloride organic HAP. In the final rule we are no longer requiring control of streams above a specified flowrate. The changes are discussed in section V.E.2 of the preamble to the final rules.

13.1.4 Sampling/Analysis Methods

Comment 13.1.4.1 : Two commenters (0146, 0153) asked that wastewater sample holding times be changed. Through the operation of 40 CFR 63.11980(a)(2)(i) [and 63.11960(d)(2)(i)] EPA would force the adoption of a section of M ethod 107 that requires the analysis of samples for total organic HAPs within 24 hours of collection. One commenter (0146) argued that the 24

- hour holding time in Method 107 will preclude PVCPUs from utilizing commercial outside laboratories for TOHAP sam ples, over

- riding the normal holding times established in each analytical method, and the guidance provided by SW

-13

- 74

846. The commenter (0146) stated that the 24

- hour holding time will require that each PVCPU purchase equipment and hire skilled laboratory sta ff to set up Methods 8260, 8270, 8315, and 8015. The commenter (0146) added that since these methods require purchase of gas chromatographs, mass spectrometer detectors, and a liquid chromatograph (for Method 8315), as
well as substantial associated extrac tion equipment, the capital cost per PVCPU will be large. Another commenter (0153) stated that he believes that holding time requirements should be: 1) specific to the methods to be used, 2) consistent with guidance in SW

- 846, or 3) the result of specific holding time studies that demonstrate HAP concentration stability. One commenter (0146) argued that each PVCPU should have the ability to determine how best to minimize the loss of HAP, maintain sample integrity, and determine what appropriate sample prese rvation and holding times are required. That same commenter (0146) provided the following language suggestion for §63.11980(a)(3): ―For measuring vinyl chloride, you must use Method 107 at 40 CFR part 61, hereby incorporated into part 63 as an Appendix. Ex isting EPA approved modifications to Method 107, obtained for use at PVCPUs, continue to be authorized for analysis of vinyl chloride in stripped resin and wastewater.‖ The commenter (0146) noted that EPA will supersede 40 CFR part 61 with the new MACT for PVC and copolymers, therefore Method 107 (and other relevant parts of part 61) will need to be moved into part 63. Response to comment 13.1.4.1 : The comments are moot since the final rule requires daily vinyl chloride sampling using EPA Method 107 and mon thly total non

- vinyl chloride organic
HAP sampling using EPA Method SW

- 846

- 8260B along with the other methods specified in Table 10 of the final rule. We disagree with the commenter regarding moving sampling methods in part 61 to part 63. EPA Method 107 in part 61 is not part of the vinyl chloride NESHAP but is in Appendix B of part 61; therefore, there is no reason to move them if the requirements of the part 61 vinyl chloride NESHAP no longer apply.

Comment 13.1.4.2 : Two commenters (0140, 0146) took issu e with Method 305. One commenter (0140) recommended that Method 8015 be required for the determination of methanol in wastewater rather than Method 305. One commenter (0140) stated that Method 305 uses polyethylene glycol (PEG) as an extracting solvent, wh ich is a poor solvent for water soluble, highly polar organics such as methanol. The commenter (0140) added it employs recovery correction factors based on spiked QC sample recovery, a technique that has traditionally been avoided for environmental chemist ry measurements. The commenter (0140)13

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argues that the current process for method selection is confusing. EPA should minimize the number of methods employed and present a selection table in the final that is parameter, method and matrix specific.
One comme nter (0146) recommended replacement of Method 305 with SW

- 846 Method 8015. The commenter (0146) also recommended that, in addition to SW

- 846 Method 8260B, Method 305, Sections 6.0 and 7.0 (for methanol only) and EPA Method 107, other SW

- 846
methods be adde d to ensure analysis of all potential PVC process

- related HAPs, specifically: 1) Method 8260B for volatile organic compounds; 2) Method 8270C for semi

- volatile compounds; 3) Method 8315A for aldehydes, specifically acetaldehyde and formaldehyde; 4) Method 8015C for alcohols, specifically methanol; and 5) EPA Method 107 for VCM. All five (5) of these methods should be listed in 40 CFR 63.11980(a)(2). Response to comment 13.1.4.2 : We agree with the commenters, and the final rule now requires use of EPA Method 107 for vinyl chloride and, for total non

- vinyl chloride organic HAP, use of EPA Methods SW

- 846

- 8260B for volatile organic compounds, SW

- 846

- 8270D for
semi volatile organic compounds, SW

- 846

- 8351A for aldehydes, and SW

- 846

- 8015C for
alcohols.

13.1.5 General

Co mment 13.1.5.1 : Three commenters (0142, 0143, 0146) asked EPA to omit the site

specific test plan review for initial testing and subsequent monthly sampling. The commenters (0142, 0143, 0146) contended that there is nothing ―special‖ about the sampling req uirements that would uniquely require review and approval of a test plan. The commenters (0142, 0143, 0146) added that other MACT standards appropriately recognize that there is no need to make each facility incur the cost and delay of writing up a formal test plan, and then getting an agency to approve the plan, before going out to do sampling. EPA could review test plans after they have been implemented given that the industrial category includes a small number of PVC and copolymers production facilities. The commenters (0142, 0143, 0146) added that the potential for civil penalties provides an ample incentive to make sure the data are valid. One commenter (0153) requested clarification that the sampling and analysis plan (SAP) cover both stripped
resin an d wastewater, be submitted once with the Notification Of Compliance Status (NOCS), and that the plan be available for agency inspections at the PVC site.13

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Response to comment 13.1.5.1 : We disagree with the commenters‘ suggestion to do away with site specif

ic evaluation test plan review. Just as in other plan development, source owners or operators benefit from having to put down on paper how their emissions testing will be performed, leading to informed staff and reduced emissions. Note that while the final rule requires submission of the test plan to the Administrator for approval when CEMS are used; however, submission of the test plan to the Administrator for approval when CPMS are used is required only when requested by the Administrator. We believe the requirements of §63.11990(a) to keep copies of the test plans as records will ensure the plans are available for agency inspections.

Comment 13.1.5.2 : One commenter (0146) requested clarification about several sections of the MACT general conditions cited in 40 CFR 63.11980(a)(2): Section 63.7(c)(3) is entitled ―Approval of site

- specific test plan‖ and only addresses EPA disapproval of site

- specific test plans, including the provision that EPA failure to approve a test plan does not relieve the owner or o perator from legal responsibility for compliance. Section 63.7(e)(2)(i) is cited, which subparagraph appears to only address EPA approval of minor changes to a test method. Sections 63.8(d) and (e) are also cited as required provisions for submitting the test plan for approval, but these citations are specifically for continuous monitoring systems (―CMS‖) and appear to be inapplicable for a site

- specific wastewater test plan. Response to comment 13.1.5.2 : The comments are moot, as the test methods for

wast ewater in the rule no longer contain references to §63.7(c)(3) or §63.7(e)(2)(i).

Comment 13.1.5.3 : One commenter (PH

- BR

- 0011) argued EPA‘s threshold for triggering vinyl chloride reductions is above the capacity of any PVC manufacturer. The commenter (PH

BR

- 0011) added that the result is that all existing manufacturers are exempt from wastewater
stream reductions. Response to comment 13.1.5.3 : We are not able to determine what the commenter is referencing. The rule has a limit that applies to wastewater regardless of capacity. The wastewater emission limit will require reduction of vinyl chloride and total non

- vinyl chloride organic HAP emissions.13

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Comment 13.1.5.4 : One commenter (0144) noted the proposed rule does not contain any requirements related to maintenance, shutdown or turnaround for wastewater. The commenter (0144) stated that some of the earlier promulgated process industry MACT standards such as the HON and the MON contain specific provisions addressing management and control of
maintenance w astewater streams containing HAP at the point of determination. The commenter (0144) requested that EPA consider these maintenance, startup, and shutdown activities and provide appropriate provisions in the rule to address related emissions from these stre ams. Response to comment 13.1.5.4 : Separate requirements for maintenance wastewater have been added to the final rule. We are requiring that facilities comply with the HON work practices
for maintenance wastewater. See discussion in Preamble Section V.F.4. Our discussion of startup
and shutdown are in section 24 of this document.

13.2 MACT Floor

Comment 13.2.1 : One commenter (0146) stated that EPA proposed two different compliance periods for total organic HAP (TOHAP); 1) the first 12 month period following
dem onstration of initial compliance, and 2) all subsequent months. The commenter (0146) also argued that in order to use the first alternative, facilities would need to ensure that any modifications necessary to reduce TOHAP are in place and operating within 2 years of the final MACT rule effective date (rather than the 3 years typically provided). The commenter (0146)
added that o therwise, facilities may not be able to ensure that the first month of rolling average calculation is in compliance. Alternatively, the commenter (0146) stated that EPA should allow a monthly TOHAP limit for the first 11 months to avoid forcing facilities into non

- compliance simply because the facilities must comply with a computed rolling 12

- month average. Response to comment 13.2.1 : In the final rule we have revised the MACT floor limits for

process wastewater , and we revised the compliance requirements by removing the 12 month rolling average for compliance with the total organic HAP limit. The final rule requires that a monthly mea surement of the wastewater be taken to determine compliance with the total non

vinyl chloride organic HAP limit. See sections V.E.2 and V.F of the preamble to the final rules for the response to this comment.13

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Comment 13.2.2 : One commenter (0146) asked th at EPA treat non

- detects in the same fashion for wastewater as it does for other emissions streams for purposes of calculating MACT
floors. Response to comment 13.2.2 : There were a limited number of vinyl chloride concentration values reported as below det ection limit in the data received from the Vinyl Institute for process wastewater. In calculating the final vinyl chloride limits for process wastewater, we used the UPL to account for variability and also performed a representative
method detection level analysis. The methodology used to determine a representative method
detection level was consistent for both stripped resins and process wastewater. Details of these calculations can be found in the technical memoranda that support the final rule available in the
docket.

Comment 13.2.3: One commenter (0146) disagreed with EPA‘s assertion that maintenance wastewater is not currently regulated by 40 CFR part 61. The commenter (0146) pointed out that the definition of in

- process wastewater at §61.61(j) is suff iciently broad to capture any water coming into contact with VCM or PVC. The commenter (0146) also stated that the only water exempted from this definition, and thus the requirement for treatment, is water used to wash out equipment ―after the equipment ha s already been opened to the atmosphere in accordance with §61.64(a)(2) or paragraph (b)(6) of this section.‖ [See 40 CFR 61.68(b)(9)(i)]. The commenter (0146) maintained that the proposed rule contains the same equipment opening standards at §63.11955 as the current rule at §§61.64(a)(2) and 61.68(b)(6), and that because the equipment had already met the equipment opening standards requiring removal of HAP [40 CFR 61.64(a)(2)] from reactors and [§61.68(b)(6)] other equipment, contact
with HAP is minimized and treatment deemed unnecessary. Response to comment 13.2.3 : The requirements for maintenance wastewater have been
revised for the final rules. We do recognize that it may not be feasible to collect wastewater resulting from maintenance activities at PV C facilities such that it could be contained and routed to a wastewater treatment system, PVC facilities reported a variety of different work practices used to control emissions from maintenance wastewater. However, the facilities did not provide
sufficien t description or information necessary to determine the effectiveness of any one work practice alone or relative to other work practices. In the final rule we have decided to incorporate the maintenance wastewater work practice requirements used in other E PA standards, such as the14

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HON. These work practice standards include preparing a description of maintenance procedures for management of wastewater generated from the emptying and purging of equipment in the process during temporary shutdowns for inspectio ns, maintenance, and repair and during periods which are not shutdowns. As done in the HON, facilities can effectively implement these work practices to prevent or mitigate the emissions of HAP from wastewater generated during
maintenance activities. See s ection V.F.4 of the preamble to the final rules.



### 14.0 COMPLIANCE DATES

Comment 14.1 : One commenter (0153) contended that EPA should add a provision to the PVC MACT allowing a facility to request an extension of a year or more of the compliance
deadline in the event of force majeure, or in order to coordinate facility upgrades until after the EDC/VCM MACT is finalized. The commenter (0153) stated that because some PVC facilities will also be subject to the pending EDC/VCM MACT, such facilities will not be able to begin construction of certain necessary upgrades for PVC MACT compliance until after the
EDC/VCM MACT is finalized. The commenter (0153) added that although the provision in subsection (e) allows operators to assert a claim of force majeure in connectio n with an initial performance test, the commenter asserts that EPA should add language to the final rule to allow an operator to obtain a temporary extension if agency review and delay or an event of force majeure occurs while negotiations are under way ov er a proposed test plan. Response to comment 14.1 : Commenters have requested additions to the provisions for a force majeure presented in §63.11900(e). The language in §63.11900(e) is provided as a clarifying courtesy on where the force majeure provisions are located in case affected sources should need them. Our intent to make the performance testing provisions of 40 CFR 63.7(a)(4) applicable to subpart HHHHHHH of part 63 is evident in Table 4 of the final rule. The flexibilities provided in §63.7(a)(4) should address the commenter‘s concerns

. We have not proposed revised standards for EDC/VCM facilities nor have we proposed to revise the HON MACT to address emissions from EDC/VCM sources. Therefore, we cannot extend the PVC compliance dates at this tim e to coincide with any future rulemakings for EDC/VCM sources.

Comment 14. 2 : One commenter (0146) contended that in consideration of the intent of the CAA ―Special Rule‖ to enable compliance with a reasonably proposed standard, EPA should15

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revise the final rule to allow for new sources to come into compliance three years after the final rule is promulgated. Two commenters (0146, 0144) argued that according to CAA §112(i)(2), sources that commence construction or reconstruction after proposal but before prom ulgation are not required to comply with promulgated standards until the date 3 years after the date of promulgation, and thus the proposed PVC MACT is unjustified in requiring new sources that start construction between proposal and promulgation to comply with the proposed standard upon startup. One commenter (0144) requested that the phrase "...effective date of publication of the final rule in the Federal Register..." replace all references to May 20, 2011 in proposed sections 63.11870(b), (c), and (d), in order to allow for continued expansions of PVC production capacity. Response to comment 14. 2 : While the commenters refer to the ―Special Rule‖ provisions of CAA Section 112(i)(2), included in the General Provisions as 40 CFR 63.7(a)(2)(ix), they
have fa iled to support their request with any explanation of how the two conditions contained within CAA Section 112(i)(2) are satisfied for the ―Special Rule‖ provision to apply to this rulemaking. Considering the final rule requirements, we do not believe condi tion (A) of CAA Section 112(i)(2) ―the promulgated standard, limitation or regulation is more stringent than the standard, limitation or regulation proposed‖ applies. See preamble Section IV.B and IV.F for discussion on when sources must comply with the ma jor and area source standards and initial compliance requirements. Additional clarification on what a ―new affected source‖ means is provided in preamble Section V.A.



### 15.0 DEFINITIONS AND TERMINOLOGY

Comment 15.1 : One commenter (0143) argued that EPA should revise the proposed rule to promote the use of recovery devices whenever possible, and to exclude recovery devices from the definition of "destructive control devices." The (0143) commenter provided the agency a proposed definition of a recovery device. Three commenters (0143, 0146, 0153) disagreed with the agency‘s proposal to classify all recovery devices as control devices, and see no rationale for why "process condensers" are the sole type of "recovery device" that would be excluded from being a "cont rol device." All three commenters (0143, 0146, 0153) propose that EPA amend the definition of "recovery device" as follows: "For purposes of this subpart, recovery devices may or may not be control devices ; " and15

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that "control device" be defined as: ―...wit h the exceptions noted in this definition, a combustion device, some recovery devices, some recapture devices, or any combination of these devices used primarily to comply with this subpart.‖ Response to comment 15.1: See preamble Section V.D. for discussi on on a very similar comment regarding calling vent gas absorbers ―recovery devices‖ and not ―control devices.‖ In our response to the comment, which applies to these comments as well, we point out that the final rule emission limits apply at the point whe re the gaseous stream is released to the atmosphere. The rule does not require that affected sources use a specific control or recovery device to meet the process vent limits, and the final emission standards are not based on whether a vent gas absorber is classified as a recovery device or control device. In the final rule we define recovery devices as ―an individual process component capable of and normally used for the purpose of recovering chemicals for fuel value ( i.e. , net positive heating value), use , reuse or for sale for fuel value, use or reuse.‖ We also state that ―for purposes of this subpart, recovery
devices are control devices.‖

Comment 15.2 : One commenter (0134) requested that EPA add the following sentence to the definition of wastewater ―W ater used to wash out equipment after the equipment has already been opened to the atmosphere in accordance with §63.11955 is not wastewater.‖ The commenter (0134) contended that the proposed definition of wastewater is essentially the same
definition as i n

- process wastewater (40 CFR 61.61(j)), and that this addition would preserve and carry forward the practice of minimizing HAPs in wash waters by requiring that equipment meet the applicable opening standards before the introduction of water for cleaning. Response to comment 15.2: See preamble Section V.F.3. for discussion on emission source requirements for wastewater, including steps taken since proposal to address maintenance wastewaters. In the final rule maintenance wastewater is not subject to the sam e requirements as process wastewater but instead is subject to work practice standards. Therefore, the additional language that the commenter suggested is not necessary for the wastewater definition.

Comment 15.3 : One commenter (0146) proposed a new defi nition for maintenance wastewater and operational standard that addressed PVCPU

– specific maintenance wastewater generating activities. The commenter (0146) then recommended that EPA promulgate a PVC
MACT definition that addresses PVCPU

– specific maintenance wastewater generating activities15

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and requires PVC MACT affected units to follow HON‘s maintenance wastewater requirements at 40 CFR. §63.105, with a slight variation to remove references to a Startup, Shutdown,
Malfunction Plan. Response to comment 15.3: See preamble Section V.F.3. for discussion on emission source requirements for wastewater, including steps taken since proposal to address maintenance wastewaters. In the final rule maintenance wastewater is not subject to the same requirements as

process wastewater but instead is subject to work practice standards. Furthermore, we have clarified that certain safety

- related streams are not considered wastewater. These two revisions in the final rule are consistent with wastewater provisions in other MACT st andards, such as the
HON and MON.

Comment 15.4 : Several commenters (0134, 0143, 0146, 0142) addressed the proposed
definition of in

- process wastewater. One commenter (0134) noted that although EPA asserted that maintenance wastewater is not currently regu lated by 40 CFR part 61, the definition of in

process wastewater at §61.61(j) is sufficiently broad to capture any water coming into contact with VCM or PVC. The commenter (0134) goes on to request that the agency add the following
sentence to the definiti on of wastewater: ―Water used to wash out equipment after the equipment has already been opened to the atmosphere in accordance with §63.11955 is not wastewater.‖ The commenter (0134) believe this addition will preserve and carry forward the practice of
mi nimizing HAPs in wash waters by requiring that equipment meet the applicable opening standards before the introduction of water for cleaning. Another commenter (0143) contends that maintenance wastewater streams should be regulated independently of in

- proc ess wastewater and warrants use of a work practice standard because the capture of maintenance wastewater
emissions is infeasible. Another commenter (0142) requested that the term ―point of determination‖ be used throughout the wastewater provisions and t hat the term ―point of generation‖ be deleted from the rule entirely to be consistent with other part 63 NESHAP and to prevent confusion. Response to comment 15.4: We disagree with the commenter, t he part 61 definition for
in

- process wastewater is not incl uded in the final rule since the definition of wastewater and process wastewater have been revised. See preamble Section V.F.3 for discussion on emission source requirements for wastewater, including steps taken since proposal to address maintenance

wastew aters. In the final rule maintenance wastewater is not subject to the same requirements as15

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process wastewater but instead is subject to work practice standards. We have also removed all terminology related to ―point of generation‖ and ―point of determinati on.‖ These terms created confusion for determining compliance with the standards. The final rule includes simplified language regarding where process wastewater streams must be tested to determine if treatment is required to meet the process wastewater lim its.

Comment 15.5 : Several commenters (0153, 0146, 0142) addressed the proposed definition of storage vessels. One commenter (0153) supported the proposed definition in section § 63.12005. Some commenters (0146, 0142) disagreed with the proposed definition , stating that storage vessels containing gases and solid materials should not be included in the definition of storage vessels, and that the proposed definition is unprecedented when compared to the storage
vessel definitions of some other MACT standards (such as Organic Liquids Distribution MACT, HON, and others). Response to comment 15.5: We acknowledge one commenter‘s support on our proposed definition of storage vessel, and disagree with commenters that would have us remove storage vessels containing g ases and solid materials from the definition. As we discuss in preamble Section V.A. on affected sources, we have revised the affected source definition to be the collection of one or more PVCPU and associated heat exchange systems, wastewater and process wastewater treatment systems, surge control vessels, and storage vessels. Therefore, storage vessels are included as part of the PVC production affected source, and materials in solid, liquid and vapor phases are stored in the PVC production process. To ac count for this, the final rule, in table 3, delineates the appropriate compliance requirements for storage vessels, depending on capacity and material vapor pressure that apply to each storage vessel type.

Comment 15.6 : One commenter (0142) proposed th at pressure vessels be excluded from the definitions of storage vessels and process tanks because they have no emissions to the atmosphere. The commenter (0142) point out that EPA has listed pressure vessels as an example in the definition of process tank and also in the definition of storage vessel, although the storage vessel definition specifically excludes process tanks from being storage vessels; thus, the definitions should be altered accordingly.15

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Response to comment 15.6: We disagree with the comment er. Pressure vessels can be used as storage vessels or process tanks. Pressure vessels are used to store liquids or gases and

are designed not to vent to the atmosphere as a result of compression of the vapor headspace in the pressure vessel during filling of the pressure vessel to its design capacity.

Comment 15.7 : One commenter (0143) requested clarification of the term ―in vacuum service‖ with respect to the requirements in the proposed rule for closed vent systems which
differentiate between "closed vent systems" and "closed vent systems in vacuum service.‖ The commenter (0143) recommended the term be defined as "the process component is operating at an internal pressure that is at least 5 kilopascals (kPa) (0.7 pounds per square inch absolute)
below ambient pressure." Response to comment 15.7: The final rule provides the following definition that addresses this comment: ― In vacuum service means that the process component is operating at an internal pressure that is at least 5 kilopascals (kPa) (0.7 po unds per square inch absolute) below ambient pressure.‖

Comment 15.8 : One commenter (0153) stated that clarification is needed for the use of the terms ―operating scenario‖ and ―new operating scenario‖ because the current definitions are
unclear and have ―circular references,‖ making it difficult to determine what types of events constitute a new operating scenario. Response to comment 15.8: The term ―operating scenario‖ has been defined in the subpart, and means any specific operation of a regulated proce ss as described by reports specified in §63.11985(b)(4)(ii) and records specified in §63.11990(e)(4). Although we believe the language of the rule is clear on what constitutes a ―new operating scenario‖ in §63.11985(b)(4)(ii), we will clarify here that a ― new operating scenario‖ is an operating scenario that has been operated since the time period covered by the last compliance report and has not been submitted in the notification of compliance status report or a previous compliance report.

Comment 15.9 : One commenter (0134) requested that the term ―hard piping‖ be replaced with the phrase ―closed conveyance system designed and operated to prevent exposure to the15

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atmosphere‖ or other similar wording, because ―hard piping‖ is not defined in subpart
HHHHHHH. Response to comment 15.9: In the final rule, we have added a definition for hard piping

–

― hard piping means pipes or tubing that are manufactured and properly installed using good engineering judgment and an appropriate standard method published by a con sensus

- based standards organization if such a method exists or you may use an industry standard practice.
Consensus

- based standards organizations include, but are not limited to, American National Standards Institute (ANSI, 1819 L Street, NW., 6th floor, W ashington, DC 20036, (202) 293

– 8020, http://www.ansi.org).‖

Comment 15. 10 One commenter (0146) proposed that the definition of bypass should be modified to include an exemption for attachments for temporary connections used for maintenance activities, so that operators may safely maintain their equipment without falling out of compliance with the rule. The commenter (0146) also stated that EPA is proposing to define ―bypass‖ as the following: to direct a process vent or closed vent system stream to the

atm osphere such that it does not first pass through an emission control device [76 FR 29596 (to be codified at 40 CFR. 63.12005)]. The commenter (0146) argued that this definition fails to provide an exemption for attachments for temporary connections used fo r maintenance activities. The commenter (0146) stated that maintenance conducted on closed vent systems is always used with a connection to a vacuum for removing or adding materials; under the HON, maintenance valves are exempt from process vent monitoring requirements because they are not truly capable of diverting the vent stream from a control device to the atmosphere. The commenter (0146) concluded by stating that in the final PVC MACT rule, EPA must provide the same types of exclusions as in prior stan dards so that operators may safely maintain their equipment without running afoul of the rule. Response to comment 15.1 0 : We disagree that there is a need for exemptions and exclusions as suggested by the commenter to the definition of ―bypass.‖ To the ext ent the commenter is referring to wastewater from maintenance activities, we suggest reviewing preamble Section V.F.3. for further discussion on our understanding of maintenance activities at PVC facilities. There is further discussion in preamble Section V.I. about our development of the definition of ―maintenance wastewater‖ that would seem to address many of the commenter‘s concerns. Lastly, preamble Section IV.A. states that a PVCPU includes ―equipment,‖ which in15

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turn includes items such as open

- ended v alves or lines, sampling connection systems, and pressure relief devices needed for safety purposes. Therefore, equipment leak provisions do apply to these types of equipment.

Comment 15.1 1 : One commenter (0146) proposed that a definition be added for the term ―by

- product,‖ as used in the proposed PVC MACT definition of storage vessel. They suggested using the HON definition which is as follows: ―By

- product means a chemical that is produced coincidentally during the production of another chemical

. ‖ The com menter (0146) contended that to account for this, the final rule, in table 3, delineates the appropriate compliance requirements for storage vessels, depending on capacity and material vapor pressure that apply to each storage vessel type. The commenter (0 146) did not believe the term ―by

- product‖ would provide any additional clarity on applicability of the rule. Response to comment 15.1 1 : We do not agree that a definition of ―by

- product‖ is needed
for the final rule nor do we agree that the proposed HON d efinition for ―by

- product‖ is appropriate for this industry since no ―by

- products‖ are made.

.

Comment 15.1 2 : One commenter (0146) stated that gasholders meet the proposed PVC MACT definition of ―surge control vessel,‖ not ―fixed roof" storage vessel, or ― floating roof‖ storage vessel, or ―process tank.‖ Thus, the commenter (0146) stipulates that gasholders should be regulated as surge control vessels. Response to comment 15.1 2 : We agree that a gasholder meets the definition of a ―surge
control vessel‖ and have revised the definition to clearly include gasholders. See preamble Section V.F.6. for discussion of the final rule standards for gasholders.

Comment 15.1 3 : One commenter (0144) requested that EPA provide a definition on what
constitutes a "double out board seal" as is required to be installed on reciprocating compressors. Response to comment 15.1 3 : Since promulgation, we have revised the language for reciprocating compressors to read that HAP emissions ―are to be minimized by either installing
double m echanical seals or equivalent equipment, or by complying with the requirements of 40 CFR part 63, subpart UU for reciprocating pumps, rotating compressors, reciprocating compressors and/or agitators.‖ In 40 CFR 63 subpart UU the term ―dual mechanical seal pumps‖15

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is synonymous with ―double mechanical seals.‖ See §63.1026(e)(1)(ii) for options of requirements for the dual mechanical seal system contained in 40 CFR 63 subpart UU.

Comment 15.1 4 : One commenter (0142) requested clarification for what constitute s a ―release indicator.‖ The commenter (0142) has a series of indicators and alarms currently in place, and clarification of this term would allow him to determine the validity of his system. Response to comment 15.1 4 : See the discussion on equipment leaks in preamble Section V.F.1 for response to similar comments regarding pressure relief devices (PRD) and associated monitoring requirements. As discussed in the preamble and in the final rule, PRDs are required to be equipped with indicators that can identi fy and record the time and duration of each pressure
release.

Comment 15.1 5 : One commenter (0142) requested that the definition of ―maximum true vapor pressure‖ be revised to clarify whether it relates to only the stored HAP or the stored material/liquid in the vessel. The commenter (0142) stated that EPA improperly uses the terms ―stored liquid‖ or ―stored material‖ instead of ―stored HAP‖ in the preamble when referring to the maximum true vapor pressure (defined as ―the equilibrium partial pressure exert ed by the total HAP...‖). The commenter (0142) pointed out that the maximum true vapor pressure of the liquid or material in the vessel can be different than the maximum true vapor pressure of just the HAP constituents. The commenter (0142) provided examples of preamble text in which EPA uses ―material‖ or ―liquid‖ rather than ―HAP‖ when referring to maximum true vapor pressure. Response to comment 15.1 5 : It is our intent that ―maximum true vapor pressure‖ apply to
total HAP. The definition of ―maximum true v apor pressure‖ is clear in this regard, and footnote 1 of table 3 of the final rule states that the vapor pressure criterion for the storage vessel requirements means the ―Maximum true vapor pressure of total HAP at storage temperature.‖

Comment 15.1 6 : O ne commenter (0142) stated that clarification is needed for the use of the terms ―deviation‖ and ―violation.‖ The commenter (0142) stipulates that though these terms are used interchangeably throughout the proposed rule, the use of the term ―violation‖ is incorrect because not all deviations are necessarily violations of the regulatory requirements. Response to comment 15.1 6 : The term ―deviation‖ is defined in §63.11890(d) and means any of the seven cases identified in that paragraph. While not all deviatio ns are necessarily15

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violations of the rule‘s emissions limits, the deviations identified in §63.11890(d)(5)(i) through (iv), such as a pressure relief device in HAP service that discharges directly to the atmosphere,

are immediate violations and have been specified as such. Moreover, all deviations must be recorded and reported as part of the semi

- annual report where a compliance evaluation of the source, including deviations, will be initiated.

Comment 15.1 7 : One commenter (0142) requested that EPA inclu de provisions for process condensers that cannot meet the process condenser demonstration requirements because
the condenser is not intended to remove HAP. The commenter (0142) s tate d that it is possible to have a process condenser (by the proposed definit ion) whose purpose is not to condense HAP material, and such a condenser may be operating properly yet unable to meet the demonstration requirements specified by the rule. The commenter (0142) suggest ed including such condensers in the Notification of Comp liance status report with an explanation of why the process condenser requirements cannot be met, even when the condenser is operating as designed. Response to comment 15.1 7 : In response to this comment, we first want to note that the
definition of control device expressly states that ―Process condensers are not control devices.‖ The final rule also defines a process condenser as ―a condenser whose primary purpose is to recover material as an integral part of a batch process.‖ The definition of ―process con denser‖ goes into further detail on what may constitute a ―process condenser‖ and cases where this definition does not apply. Therefore, we have acknowledged that for this rulemaking, process condensers are not control devices, and may be followed by a con denser acting as a control device or another type of control device. Regarding Notification of Compliance status reports, as specified in §63.11950(c)(ii), the final rule does not require a demonstration that a process condenser is properly operated if the process condenser is followed by a condenser acting as a control device or if the control device is monitored using a CEMS.

Comment 15. 1 8 : One commenter (0142) requested clarification for the terms ―annually,‖ ―once per calendar year‖ and ―every 12 month s,‖ saying that a requirement to conduct inspections  ̳ ̳annually,‘‘ could be read to mean in every calendar year, no later than the date 1 year after the previous inspection, or in the same month every year. The commenter (0142) proposes that a definition o f ―annual‖ be added to the rule, saying that ―annual‖ and ―every 12 months‖ mean once per calendar year.16

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Response to comment 15. 1 8 : It is our intent that where the terms ―annually‖ and ―every 12 months‖ have been applied, an owner or operator may perform t he required task at any time during the specified period, provided the task is conducted at a reasonable interval after completion of the task during the previous period. ―Calendar year‖ is defined in the final rule.



### 16.0 EMISSION LIMITS, OPERATING LIMITS, AN D WORK
PRACTICE STANDARDS

Comment 16. 1 : One commenter (0142) stated they believe that the PVC MACT rule sets
standards that are more restrictive than standards set for other similar MACT subparts; some of EPA‘s decisions seem political and not based on co llected data. One commenter (0141) requested that the PVC MACT rule should include Flexible Approaches consistent with Section
4 of Executive Order 13563. The commenter (0141) stated that EPA should provide industry with a menu of pollution control and rec overy equipment to achieve reductions all based on the best five performers. Response to comment 16. 1 : The proposed and final standards are based on the data
available to us

. The legal framework for establishing MACT standards is set forth in section 112( d) of the CAA, as discussed in the preamble to the proposed rule, and EPA‘s implementation of the MACT program as directed by the CAA may result in different levels of stringency for different emission points and HAP in different source categories. The pr oposed
and final PVC MACT standards are based on the data relevant to the PVC source category and
available to EPA , as provided by the PVC industry . Based on additional information provided after proposal, we have revised the MACT floor and beyond the floo r analyses in several respects for the final rules. See section V.E of the preamble to the rule for our discussion of the se changes. Additionally, in the proposed and final rules we generally set emission limits and did not specify control technologies tha t should be used to meet the emission limits. A facility can use any control technology or technique to meet the limits , which provides flexibility and choice in complying with the final standards

. We provide compliance and operating parameter requirement s for common controls that might be used for different types of emission points. For the impacts analysis, we estimated the costs based on likely controls that would be used by facilities. However, we did not prescribe the17

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technology that facilities should use to meet the limits. We believe the final rule is not
inconsistent with Section 4 of Executive Order 13563.



### 17.0 GENERAL SUPPORT OF OTHER COMMENTERS

Comment 17.1 : One commenter (0134) stated that he agree s with the recalculated process
vent MACT floors a s submitted by the VI Working Group (0146). The commenter (0134) provided the recalculated process vent MACT floors in a table of page 14 of hi s comments. Response to comment 17.1 : EPA has addressed the statements of all commenters, and responses to specif

ic comments are found in the appropriate section of this document and in the preamble to the final PVC standards

.

Comment 17.2 : Six commenters (0126, 0133, 0136, 0147, 0153, 0142) support the comments submitted by the American Chemistry Council (ACC). ACC themselves also expressed support for comments submitted by ACC Vinyl Chloride Health Committee and ACC‘s chlorine Chemistry Division. Response to comment 17.2 : EPA has addressed the statements of all commenters, and responses to specific comments are fo und in the appropriate section of this document and in the preamble to the final PVC standards.

Comment 17.3 : Twenty

- one commenters (0126, 0131, 0133, 0134, 0136, 0137, 0139, 0141, 0142, 0143, 0145, 0147, 0151, 0152, 0153, 0156, 0158, 0159, 0160, 0164, PH

- BR

- 0009) expressed support for comments submitted by the Vinyl Institute (VI). Another commenter (0135) urged EPA to consider the technical comments submitted by the Vinyl Institute and other
stakeholders. One commenter (0134) particularly supported the argument submitted by VI that the heat exchange system leak action levels for new and existing sources and monitoring frequencies for new sources are without precedent and the most stringent issued by EPA to date. Commenter (0134) also specifically express ed support for the VCM and TOHAP limits for suspension resin produced at new and existing sources submitted by VI. One c omment er (0139) expressed support for the floor limits proposed based on sub

- categorization within VI‘s comments. Another

c ommenter (014 2) supported VI‘s comments on delay of repair provisions for heat exchanger17

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leaks. The c ommenter (0145) agreed with the comments VI submitted regarding the impact on PVC resin suppliers and suggested changes based on scientific data and the final impact on our economy. Commenter 0158 also supported VI‘s comments regarding the impact of PVC MACT regulations on suppliers. Commenter (0153) specifically supported the recalculation of the stripped resin emission limitations, use of Method 107 data in lieu of Met hod 8260 for vinyl chloride data, and recalculation of RVCM limits at the wastewater stripper. Commenter (0160) supported VI‘s comments pertaining to gasholders and argues that methods enumerates within VI‘s comments are the only practical and effective me ans of controlling emissions from these unique sources. Response to comment 17.3 : EPA has addressed the statements of all commenters, and responses to specific comments are found in the appropriate section of this document and in the preamble to the final PVC standards.

Comment 17.4 : Three commenters (0134, 0141, 0153) supported the comments submitted by Occidental Chemical Corporation/OxyVinyls (OCC). Response to comment 17.4 : EPA has addressed the statements of all commenters, and responses to specific c omments are found in the appropriate section of this document and in the preamble to the final PVC standards.

Comment 17.5 : One commenter (0154) supported comments submitted by PolyOne Corporation, Shintech Inc., Westlake Chemical Corporation, Formosa Pla stics Corporation, Society of the Plastics Industry (SPI), and Resilient Floor Covering Institute (RFCI). Response to comme n t 17.5 : EPA has addressed the statements of all commenters, and responses to specific comments are found in the appropriate section of this document and in the preamble to the final PVC standards.

Comment 17.6 : Five commenters (0133, 0134, 0141, 0151, 0152) supported comments submitted by the PVC MACT Working Group. Response to comment 17.6 : EPA has addressed the statements of all co mmenters, and responses to specific comments are found in the appropriate section of this document and in the preamble to the final PVC standards.18

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Comment 17.7 : One commenter (0133) supported comments submitted by Chemistry Council of New Jersey (CCNJ) me mber companies. Response to comment 17.7 : EPA has addressed the statements of all commenters, and responses to specific comments are found in the appropriate section of this document and in the preamble to the final PVC standards.

Comment 17.8 : Two comme nters (0136, 0149) supported comments submitted by the National Association of Manufacturers (NAM). Response to comment 17.8 : EPA has addressed the statements of all commenters, and responses to specific comments are found in the appropriate section of th is document and in the preamble to the final PVC standards.



### 18.0 IMPACTS

18.1 General

Comment 18.1.1 : One commenter (0157) expressed concern that the restrictions to emissions limits and to the number of chemicals individually regulated add significant burdens to
manufacturers

. The commenter (0157) added that a n equally effective and pragmatic approach was proposed with the vacated 40 CFR part 63 s ubpart J, in which Vinyl Chloride was used as a surrogate. The commenter (0157) stated that t he additional burden in t he proposed rule associated with the recordkeeping, reporting, sampling and testing requirements does little to reduce the quantity of HAP that is released to the atmosphere. One commenter (0147) stated that industry has already reduced chlorinated chemica l emissions to air and water significantly since 1988 and the limited reductions from the proposed rule are not warranted in light of the
substantial economic burden. Response to comment 18.1.1 : The final rule contains several revisions that reduce the

an nualized cost of the final rule by 75 percent from proposal and the subcategories and MACT floor calculations have been revised resulting in revised emission limits. These changes reduce the burden of the rule on industry, e.g., 15 out of 16 facilities wer e determined to be able to meet the stripped resin limits without additional modifications or controls. We did not find the approach previously promulgated, which relied on vinyl chloride as a surrogate for other HAP,18

- 93

and subsequently vacated by the court to be an appropriate approach for this rulemaking. The rationale and supporting analysis for the final standards and associated compliance provisions can be found in the preamble to the final rule as well as supporting memos in the docket. We
also analyze impacts in the preamble to the final rule and provide in the docket a revised cost analysis memo

.

18.2 Air

Comment 18.2.1 : One commenter (PH

- BR

- 0010) stated that for environmental justice community members living in close proximity to PVC production faciliti es, the reductions achieved by the proposed rule are not adequate. This commenter contended that reductions would account for only 30% of the vinyl chloride and 32% of the dioxins/furans currently emitted. The commenter (PH

- BR

- 0010) noted that vinyl chlori de fugitive emissions comprise 55 to 78 percent of the total vinyl chloride air emissions and that even with the proposed standards
the ambient air will continue to be contaminated with HAPs. Response to comment 18.2.1 : EPA believes that the final rule re duces emissions from
PVC facilities under the authority provided by the Clean Air Act. I n a future rulemaking we will
conduct further analyses in a risk and technology review to determine whether any remaining
risk or developments in technology warrants re vision or updating of the final MACT standards in this rulemaking.

Comment 18.2.2 : One commenter (0144) disputed EPA‘s claim in the preamble that the proposed standard will result in significant reduction in dioxin/furan emissions. They stated that
all ni ne of their thermal oxidizers are well below the limits and, therefore, there will not be any
rule

- related reductions on account of the proposed standard

. Response to comment 18.2.2 : While the limits may not significantly reduce the
CDD/CDF emissions at t he particular facility the commenter describes, the final emission
standard s will reduce CDD/CDF emissions overall from the PVC production source category

.

Comment 18.2.3 : One commenter (0157) recommended a change in the methodology for calculating emissi ons for the dispersion resin production process. The commenter (0157) cited the Preamble, "For stripped resins, we calculated emissions assuming that all HAP remaining in18

- 94

the resin would eventually be emitted from processes downstream of the resin stripper ." The commenter (0157) contended that in the dispersion production process this is not a correct
statement since the material is sold un

- dried as a liquid. The commenter (0157) added that the significant residual HAP is highly soluble in water and lends i tself to the total HAP residual emission reduction from the dispersion process being something approaching zero tons per year. The commenter (0157) argued that EPA needs to reevaluate those assumptions and remove from
the emissions limit those soluble HAPs in dispersion grades sold un

- dried. Response to comment 18.2.3 : The commenter did not provide any data to indicate which of their dispersion resin grades are sold un

- dried as a liquid to 1) revise our calculation of emissions from processes downstream of the resin stripper, and 2) remove from the emission limit those soluble HAPs in dispersion grades sold un

- dried. We did not receive comments from other manufacturers stating that we should re

- evaluate our estimate of emissions from dispersion resins by not assuming all HAP would eventually be emitted. Therefore, to remain consistent with our estimate of emissions from suspension, suspension blending, and copolymer resins, we have retained our assumption that all HAP remaining in the resin would eventually b e emitted from processes downstream of the resin stripper for a conservative estimate of baseline
emissions reductions.

Comment 18.2.4 : One commenter (0153) suggested further emissions need to be accounted for in the Secondary Impacts Memorandum. Citing EPA‘s claim that the use of additional steam will improve both resin and wastewater strippers, the commenter (0153) claimed there will be secondary boiler emissions related to this steam. The commenter (0153)
added that additional steam will require more f uel to boilers or additional boiler capacity, increasing greenhouse gases and other pollutants. Response to comment 18.2.4 : In the final standards we are not estimating impacts assuming the use of additional steam to meet the stripped resin or wastewater l imits. We have
estimated that 15 out of 16 sources can meet the resin limits without installation of additional controls. Our cost and impacts estimates for the one facility that we believe will need to install controls are based on replacing their existin g stripper with a new stripper that will allow the facility to meet the final stripped resin standards. We are not anticipating that additional steam will be necessary once the equipment is replaced. For wastewater, we estimated that minimal to
no addition al steam will be needed to comply with the wastewater standards. See the18

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memorandum Revised Costs and Emission Reductions for Major Sources in the Polyvinyl Chloride and Copolymers (PVC) Production Source Category.

18.3 Cost

Comment 18.3.1 : One commenter ( 0 15 7) is concerned that costs were not properly taken into account with regard to the MACT floors and the controls necessary to meet them. This

commenter (0157) calculated a dollar per ton of HAP reduced for process vents, stripped resin, wastewater, equipmen t leaks, and heat exchange systems and noted they are very high. The commenter (0157) added that t he Clean Air Act §112(d)(2) states that the cost of achieving such emission reductions must be taken into account when setting MACT standards. The commenter ( 0157) provided t he following quotes from the HON Residual Risk analysis regarding cost effectiveness of controls: "Based on this analysis, 96 percent of the facilities had cost per ton of HAP removed exceeding $12,000 per ton of total HAP reduced. The aver age cost per ton of HAP removed for controlling Group 2 wastewater streams was approximately $410,000 per ton of HAP reduced. Considering these high costs, we concluded that it is not reasonable to require additional controls for Group 2 wastewater streams , in light of the minimal risk reduction obtained if additional controls were to be imposed." (71 FR 34434, 6/14/2006) "The cost of controlling emissions from transfer operations ranges from approximately $10,000 per ton of HAP to over $100,000 per ton of HAP if there are already existing control devices that may be used to reduce emissions. If a new combustion device or vapor recovery device is also needed, the cost increases significantly. As a result, further controls for transfer operations are not
incl uded in either of our two proposed options discussed below." (71 FR 34435, 6/14/2006) The commenter (0157) contended that w ith that understanding and the latitude afforded in §112(d)(4), the agency should exercise its discretion to take into consideration the residual risk associated with the HAPs emitted from the Polyvinyl Chloride process and set the standard "with an ample margin of safety

. " Response to comment 18.3.1 : The commenter‘s concern about how costs were taken into account in determining MACT fl oors is misplaced; EPA may not consider costs in setting the MACT floor. Cost estimates associated with meeting MACT floor levels of control, such as
those in the memorandum Revised Costs and Emission Reductions for Major Sources in the Polyvinyl Chloride and Copolymers (PVC) Production Source Category , are provided for18

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informational purposes only and are not considered in determining the MACT floor. Costs and other factors may be considered in EPA‘s beyond

- the

- floor analysis, as shown in the
memorandum R evised Beyond

- the

- Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category
For the final rule, we revised the cost analyses based on comments and additional data submitted by commenters. The final rule does not incorporate the HON requirements for regulating total organic HAP as a beyond

- the

- floor option for wastewater . Instead, we have
determined the wastewater emission limit using a UPL calculation as a MACT floor compliance requirement

. Based on the available data, we bel ieve the costs associated with the final rule are sufficiently accounted for.

Comment 18.3.2 : One commenter ( 0 144) disagreed that no new PVCPU facilities will be constructed in the next five years. Economic impacts from the new source MACT should be

exa mined. Response to comment 18.3.2 : We have revised the definition of affected source and new source in the final standards. See section V.A for our discussion of the changes. Based on the revised definition and the information that we have, we do not anti cipate any PVC facilities will be subject to the new source requirements in the next five years , in which case there would be no new source cost impacts. See also section V.E.2 of the preamble to the final rule.

18.4 Non

- Air Quality Health, Environmental, and Energy

Comment 18.4.1 : Three commenters (PH

- BR

- 0004, PH

- BR

- 0005, PH

- BR

- 0010) are concerned about the inadequacy of emissions reductions from the rule. One commenter (PH

- BR

0004) contended that the proposed regulation creates too many exemptions for the PV C industry. The commenter further stated that the regulation is contrary to EPA Administrator, Lisa Jackson's, commitment to Environmental Justice, and more importantly, continues to ignore their human rights to a healthy environment. One commenter (PH

- BR

- 0005) stated that in their community they are suffering from cancer

- causing chemicals from these facilities on a daily basis, including dioxin. The commenters state that Mossville residents have an average blood
dioxin level three times the national avera ge ; t he three times the national average of dioxin in their body was researched by one of the best environmental scientists in the country, showing18

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that dioxins in the blood are the same kind of dioxins released by the industrial facilities near
Mossville. The commenter (PH

- BR

- 0004) concluded that they understand industry needs jobs, but they need their young people to live. Another commenter (PH

- BR

- 0010) encouraged EPA to reduce the quantity of vinyl chloride, hydrogen chloride, dioxins and furans, and haz ardous air pollutants emitted by further tightening up the emission limits in the proposed rule. The commenter (PH

- BR

- 0010) added that d ioxins and furans are released and have the potential to and, in fact, have contaminated and bio

- accumulated in the bodi es of the human population in
the fence line communities of PVC facilities. The commenter (PH

- BR

- 0010) stated that the reduction in emissions proposed by EPA will reduce the exposure of the Environmental Justice communities, but there will still be unaccep table levels of exposure to vinyl chloride, dioxin and furans, and hazardous air pollutants in the air of these communities. Response to comment 18.4.1 : In accordance with section 112(d)), of the CAA , this final
rule sets technology

- based emission standard s for major sources pursuant to section 112(d)(2) and (d)(3) that will reduce emissions associated with the PVC source category. After the sources in the category comply with the final MACT standards, we will determine in a future rulemaking
whether unacce ptable health risks remain from the PVC facilities that are the subject of the
MACT standards , see section 112(f)(2) , and if so, we will take further action to eliminate any unacceptable risks. We also recognize that some communities may face greater risk s due to exposures to multiple chemicals through multiple media. This rule sets emission standards for hazardous air pollutant emissions from the PVC production source category . Accordingly, the
rule does not address other sources of emissions that may pose risk to a community. For that reason, we continue to recommend that communities work with State and local governments to address risks of a more cumulative nature based on the unique characteristics of those
communities and industries located in them

. We disagree that this regulation is contrary to EPA Administrator Lisa Jackson‘s commitment to environmental justice. In order to determine the potential for disproportionate impacts on minority and low income populations that this rule could help reduc e or eliminate, a demographic analysis was conducted. Please see the preamble to final rule and related technical support materials for a discussion of the demographic analysis. EPA has determined that this final rule will not have disproportionately high and adverse human health or environmental effects on minority or low

- income populations because it increases the level of environmental protection for all affected populations without having any disproportionately high and adverse18

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human health or environme ntal effects on any population, including any minority or low

- income population. As explained above and in the preamble to the final rule and the technical memorandum
entitled Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the
Po lyvinyl Chloride and Copolymers (PVC) Production Source Category
, we revised the final standards based on new data received in response to the proposal

. In response to comments and after consideration of the data in the record, we also created additiona l subcategories for process vents and stripped resin . As a result of these changes, we revised the emission standards for process vents and stripped resin s . We also made revisions to the requirements for process wastewater and heat exchange systems. For mo re information on the changes to the emission limits, with a particular emphasis on changes to emission limits for vinyl chloride, hydrogen chloride, total organic HAP and dioxin and furans, please see the final rule and associated technical support materi als.. Further analysis to determine whether any additional reductions in
emissions are needed will be conducted pursuant to section 112(d)(6) and (f)(2) after industries have complied with these new final standards.

Comment 18.4.2 : Two commenters (0126, 0147) expressed concern that the proposed
MACT rule imposes a high economic burden for limited environmental or public health benefit. One commenter (0126) contended that the additional cost for complying with the proposed MACT standard cannot be justified

. One commenter (0126) argued that existing regulatory controls for vinyl chloride are well established and are considered to provide effective protection to the general population from potential, de

- minimus vinyl chloride emissions. The commenter (0126) s tated that scientific consensus considers angiosarcoma as the sole potential cancer outcome for both animals and highly exposed workers, and angiosarcomas are a very rare occurrence in the general US population (approximately 30 new cases per year), and th e diagnosis is readily apparent to medical professionals. The commenter (0126) added that existing health protective regulatory standards are effective given the extremely low incidence of this tumor type. The commenter (0126) also noted that EPA‘s previou s review of the health hazard associated with vinyl chloride (IRIS review) concluded that concern is associated only with occupational exposures at uncontrolled high concentrations and for one target organ. The commenter (0126) cited EPA Toxicological Revi ew of Vinyl Chloride available on IRIS. This commenter (0126)19

- 99

recommended that EPA update its risk assessment for this proposed NESHAP, and submit that update for public review and comment. Response to comment 18.4.2 : This rule is being adopted to meet th e technology

- based requirements of section s 112(d)(2)

- (3) and 112(d)(5) . Section 112(d)(2) and (3) require
emissions to be controlled to levels achieved by the best

- performing sources in the category or subcategory . Section 112(d)(5) authorizes the Agen cy to set standards for area sources that require the use of generally available control technologies or management practices

. The technology

- based standards we have set in this final rule will result in HAP reductions. See the preamble for the final PV C rules for our discussion of the MACT and GACT standards adopted

. The information the commenter has provided is relevant to the Agency‘s residual risk review under section 112(f), which occurs within 8 years of the Agency setting MACT standards. See
Si erra Club v. EPA , 353 F.3d 976, 988

- 89 (D.C. Cir. 2004) (rejecting consideration of risk as part of beyond the floor analysis).



### 19.0 MACT FLOOR , GENERAL

Comment 19. 1 : A commenter (0150) argued that EPA‘s floor approach is unlawful and arbitrary. The floor s must reflect the ―average‖ emission limitation achieved by the five best performing sources. 42 U.S.C. § 7412(d)(3). The commenter (0150) stated that f loors should not be set at a level that the best performers could never exceed even when they operate p oorly or fail to maintain their control equipment. The commenter (0150 stated that u sing an upper prediction limit to set standards reflecting the statistical worst performance does not yield an accurate picture of performance. Instead, the commenter (0150 ) stated, they reflect a fictional number that exceeds that ―average‖ by more than 100%. Although the commenter (0150) recognized that EPA may consider variability in calculating the best sources‘ performance , it
contended that EPA‘s method of considerin g variability, however, seeks to assure that none of the sources among those identified as best performers would ever exceed the floor level. The

commenter (0150) added t hat approach ignores the reality that sources‘ emission levels are largely within thei r control. The commenter (0150) stated that a great deal of variability may be statistically conceivable if EPA chooses a high enough prediction limit (in this case the 99th percentile) ; however, that does not mean that a well run source actually would exp erience such19

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variability. The commenter (0150) concluded that one of the main points of having emission standards is to ensure that sources not only deploy the appropriate control measures but also use those control measures properly and consistently to mi nimize emissions. Response to comment 19. 1 : In assessing sources‘ performance, we may consider variability both in identifying which performers are ―best‖ and in assessing their level of performance. Sierra Club v. EPA (Brick MACT), 479 F. 3d 875, 881

- 82 (D.C. Cir. 2007); see also Mossville Environmental Action Now v. EPA, 370 F.3d 1232, 1241

– 42 (D.C. Cir 2004) (EPA must exercise its judgment, based on an evaluation of the relevant factors and available data, to determine the level of emissions control tha t has been achieved by the best performing sources considering these sources‘ operating variability). The Brick MACT decision indicated that floors for existing sources must reflect the average emission limitation achieved by the best

performing existing sources. The Brick MACT decision also reiterated that we may account for variability in setting floors; however, the Court found that we erred in assessing variability
because we relied on data from the worst performers to estimate best performers‘ variab ility. The Court held that ―EPA may not use emission levels of the worst performers to estimate variability of the best performers without a demonstrated relationship between the two.‖ 479 F.
3d at 882. The MACT floor limits were developed by incorporati ng variability, as has been done in
other MACT standards

. In determining the MACT floor limits, we first determine the floor, which, for existing sources in a category or subcategory with fewer than 30 sources , is the emissions limitation achieved in prac tice by the average of the top 5 existing sources, or the level achieved in practice by the best controlled similar source for new sources. In setting numerical emission limits, EPA used the lowest emissions as the measure of best performance

. We then

a ssess variability of the best performers by using a statistical formula designed to estimate a MACT floor level based on the average of the best performing sources using the expected distribution of future compliance tests. As explained in the preamble to the proposed rule we
used the UPL because for a future observation , the UPL will, with a specified degree of confidence, contain the next (or some other pre

- specified) randomly selected observation from a population. In other words, the prediction interva l estimates what future values will be, based on present or past background samples taken. For this source category, where there is a limited sampling of the source category, the UPL was used to determine variability. Because the UPL represents the value which we can expect the mean (i.e., average) of three future observations (3

-21

- 101

run average) to fall below, based upon the results of the independent sample size from the same population, the UPL reflects average emissions. The final rule makes one exception in using the UPL to calculate variability. We maintain that the MACT floor analyses conducted for the final PVC rules are appropriate and are consistent with section 112(d) of the CAA

.

Comment 19. 2 : One commenter (0157) argues that the Vinyl Chloride NE SHAP was published in the 1970‘s. At that time, the NESHAP represented a paradigm shift in the method by which emissions were regulated. EPA should take into account that in the past 19 years the production population has remained effectively unchanged, bu t the emission baseline (and residual risk) of this industry is considerably lower. Response to comment 19. 2 : For the proposed and final rule, we estimated baseline emissions for the industry based on information and data available to us that represent th e current state of the industry. See the preamble for the final rule for more details on our baseline emission
estimates for the final rule.



### 20.0 REGULATED POLLUTANTS

Comment 20.1 : One commenter (0142) requested that EPA correct that dibenzofuran is not a pol ychlorinated dibenzofuran or a chlorinated dibenzofuran (CDF) on page 29541. Response to comment 20.1 : The preamble to the proposed rule did not claim that dibenzofuran was a polychlorinated dibenzofuran or a chlorinated dibenzofuran. The preamble merely s tated that dibenzofurans are identified by name as a HAP.



### 21.0 REGULATORY OVERLAP

Comment 21.1 : One commenter (0157) stated that the apparent development of a consolidated ―Chemical Sector MACT‖ would contain significant overlap with the PVC MACT and raise q uestions of applicability, and thus the PVC MACT should be consolidated into the Chemical Sector MACT instead of promulgating the proposed rulemaking. One commenter (0157) argued that EPA should consolidate the PVC rule with the Chemical Sector MACT that
E PA is currently developing alongside the PVC MACT because the current approach creates confusion, uncertainty, and unnecessary cost to the business community as a result of the time21

- 102

and capital expense of reviewing multiple iterations of rules, especially considering that this is a

two

- step process (i.e., development of the MACT floor, followed by residual risk review). Response to comment 21.1 : The response to these comments is in Section V.B of the preamble to the final PVC rules. We also note that we hav e not proposed a chemical sector MACT standard. Additional delay to consider any such rules would have been inconsistent with the rulemaking deadline for PVC in the settlement agreement entered into by the Agency.

Comment 21.2 : Commenter (0134) stated tha t open

- ended lines of bypass streams are already regulated under subpart UU, §63.1033 as follows: (b) Equipment and operational requirements. (1) Each open

- ended valve or line shall be equipped with a cap, blind flange, plug, or a second valve, except as p rovided in 63.1021(b), 63.1036, 63.1037, and paragraphs (c) and (d) of this section. The cap, blind flange, plug, or second valve shall seal the open end at all times except during operations requiring process fluid flow through the open

- ended valve or lin e, or during maintenance. The operational provisions of paragraphs (b)(2) and (b)(3) of this section also apply. Response to comment 21.2: We agree with the commenter that open

- ended lines are regulated under subpart UU, and the final standards require s ources to comply with the subpart UU level 2 requirements for equipment leaks. We are specifically regulating bypass lines in this rule by requiring the installation, maintenance, and operation of flow indicators in closed vent system bypass lines or that bypass valves be secured in a non

- diverting position with a car

- seal
or a lock

- and

- key type configuration. Either of these requirements must be met to prevent and detect bypass of the control device.

Comment 21. 3 : Two commenters (0153, 0146) agreed wit h EPA‘s proposal to sunset the part 61 Vinyl Chloride NESHAP once facilities are operating in compliance with all applicable sections of the final PVC MACT rule. However, one commenter (0153) argued that the part 61 Vinyl Chloride NESHAP should remain in e ffect for PVC facilities co

- located with EDC/VCM facilities and for PVC facilities that are area sources, until rules for EDC/VCM facilities and the PVC GACT rule are finalized. The commenter (0153) requested that, under these circumstances,
EPA clarify th e overlapping and potentially conflicting requirements under the various regulations by preparing a side

- by

- side table to inventory the current part 61 requirements and22

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the corresponding new part 63 requirements, as well as to identify new requirements and any reduced requirements for area sources. One commenter (0146) pointed out that, for Title V purposes, the proposed rule should
address additional overlap issues with the part 61 VCM NESHAP. The commenter (0146) suggested language that EPA should add to the final rules. The commenter (0146) pointed out that the rule needs to be very clear about the break with the VCM NESHAP because the VCM
NESHAP directs certain affected sources to comply with part 61 subpart V for leak detection and repair. The commente r (0146) suggests that in §63.11871 (What is the relationship to 40 CFR part 61, subpart F?), after the applicable compliance date specified in §63.11875(a), (b), or (c), the rule should specify that an affected source that is also subject to the provision s of 40 CFR part 61, subparts A, F, and V, is required to only comply with the provisions of this subpart and not 40 CFR part 61, subparts A, F, and V. Response to comment 21. 3 : We have addressed overlap with the part 61 standards in the
final PVC rules. S ee the response in Section V.B of the preamble to the final rule regarding the final rule requirements when other regulations overlap with the PVC standards. Additionally, the final PVC rules are more stringent or equal to the existing part 61 NESHAP stan dards for PVC facilities for all emission points. Therefore, we are not aware of any issues or conflicting requirements between the part 61 standards and the final PVC rules.



### 22.0 RESIN MORPHOLOGY

Comment 22.1 : Several commenters (PH

- BR

- 0003, PH

- H

- 0003 , 0134 , 0151, and 0153 ) provided information on the morphology of PVC resins. The commenters stated that each PVC resin grade has unique physical characteristics known as particle morphology

. The commenters
added that t his uniqueness is necessary in order to mak e the variety of PVC products. The
commenters stated that PVC facilities need regulatory flexibility in order to produce a full complement of different resins that are used for diverse final products, such as vinyl siding, PVC pipe, window frames, electric al wiring insulations, roofing, credit cards, and a host of other applications. One commenter (0151) stated that even amongst similar grades of resins, PVC resin morphology plays a role in a resin‘s ability to be stripped of VCM and other hazardous air pol lutants (HAPs)

. One commenter (0153) stated that d ifferent grades of resin exhibit differing particle morphologies that have a significant impact on strippability, with different resultant23

- 104

levels of RVCM remaining in the PVC product

. Depending on the parti cular grades being manufactured at a suspension PVCPU, the RVCM will vary substantially depending on the weighted average production of easy

- to

- strip versus hard

- to strip grades, on a daily, monthly and annual average basis, no matter what the specific des ign and operating parameters may be for the PVCPU‘s slurry steam stripper(s). Response to comment 22.1 : We thank the commenters for their input and information. We have considered the information on morphology when developing the subcategories in the
fina l PVC rules. See section V.D of the preamble to the final PVC rules.



### 23.0 RULE

23.1 Gen e ral

Comment 23.1.1 : One commenter (PH

- BR

- 0002) supported EPA‘s selection of emission points and evaluation of HAPs. Response to comment 23.1.1 : We appreciate the input and sup port of the commenter on
this matter.

23.2 Format

Comment 23.2.1 : One commenter (0146) supported EPA‘s selection of a stripped resin format to control HAP emissions from downstream processes, as well as the concentration limit format for demonstrating complia nce using the resin stripper format

. The commenter (0146) explained that the stripped resin format is the best means and the concentration limit is the most direct way of demonstrating compliance for stripped resin. Response to comment 23.2.1 : We appreciat e the input and support of the commenter on
this matter.

Comment 23.2.2 : One commenter (0146) made the point that the proposed CPMS requirements discourage the use of recovery control devices to control emissions. The

commenter (0146) provided an example that a process absorber that produces HCl for use, as distinguished from final control device scrubbers, should not be subject to low pH limits unless it is the final emission control device before discharging to the atmosphere.24

- 105

Response to comment 23.2.2 : : The final rule requires that process vents from PVCPUs be controlled to the emission limits in the standards. The CPMS requirements only apply to the control device used to meet the emission limits. If a facility uses recovery devices as defined in
the f inal rule , such as condensers or absorbers, as part of their vinyl chloride recovery system,
the vent stream from the condenser or absorber must meet the emission limits for process vents

. See preamble Section V.D. regarding calling vent gas absorbers ―rec overy devices‖ and not
―control devices.‖ The rule does not require that affected sources use a specific control or recovery device to meet the process vent emission limits, and the final emission standards are not based on whether a vent gas absorber is classified as a recovery device or control device.



### 24.0 STARTUP, SHUTDOWN, AND MALFUNCTIONS

Comment 24.1. : One commenter (0143) contended that the proposed rule indicates that the typical exclusion for startup and shutdown events, listed in Section 63.7(e)( 1) of the general provisions, will be removed. The commenter (0143) stated that the implied assumption is that the proposed emissions limits apply during startup and shutdown, as well as during normal operations. Two commenters (0143, 0153) were concerned about THC performance testing with regard to startup, shutdown, and malfunction (SSM) events. The commenters (0143, 0153) contended that SSM events cannot be included in the scope of the proposed emissions limits if the expectation is to require complianc e performance tests under normal operating conditions, without SSM events. The commenters (0143, 0153) further argued that since stack test data did not contain startup, shutdown, or malfunction events then the emission limits should not be applicable duri ng these periods as there is no data to support this. One commenter (0143) indicated the instructions on page three of CAA section 114 request, Enclosure 1, instructed facilities not to include startup and shutdown events in the sampling period, and thus s tartup and shutdown events should be exempted. Two commenters (0143, 0153) also stated that EPA must provide clarification to indicate that performance testing need not be conducted during startup and shutdown conditions. Since the THC MACT floor data prov ided to EPA did not include SSM emissions, one commenter (0144) requested that EPA re

- analyze the MACT floor data to revise the proposed regulatory requirements or ask the facilities for additional and more specific
data related to SSM emissions. One comme nter (0153) contended that EPA should expressly24

- 106

state in the final rule whether sampling need or need not be conducted during startup and shutdown conditions. The commenter (0153) stated that proposed Table 5 indicates that the exemption in 40 CFR §63.7(e) (1) will no longer apply, which implies that startup and shutdown conditions are to be included in performance testing. The commenter (0153) pointed out that this is contrary to EPA‘s message at the public meeting on June 30, 2011 that stack testing of pro cess vents and data gathering was to be done under ―normal‖ operations, not including startup,
shutdown or malfunction events. Response to comment 24.1: The comment that asserts that the limits apply at all times, including during startup and shutdown, is correct. Based on our review of the commenters‘ concerns, we do not find any need to change or supplement the rule, which specifies the conditions under which performance testing is to be conducted. The performance testing conditions for process vents ar e described in §63.11945(b) as either maximum representative operating conditions for continuous venting or within the range of the maximum or minimum representative operating conditions that results in the highest emissions for batch venting, and
those co nditions for process wastewater are described in §63.11980(a)(1) as worst case operating conditions; the rule does not require performance testing during periods of startup or shutdown. Our approach to determining that standards should apply at all times, including periods of startup and shutdown was explained in the preamble to the proposed rule. We received no additional information indicating that conditions during startup and shutdown warrant different emissions limitations. In addition, Form F of the August 21, 2009 section 114 survey requested information from all PVC companies regarding startup, shutdown, and malfunction events. Only one respondent indicated that an emission limit was exceeded during a startup or shutdown period or
a malfunction even t but did not provide emission information or quantification for the exceedance that could be used to set separate standards for periods of startup and shutdown. We believe that the variability incorporated into the process vent emission limit calculation for each subcategory sufficiently allows for periods of concentration spiking even if they were to occur during periods of startup. Finally with regard to malfunctions, as explained in the preamble to the proposed rule, EPA has determined that CAA section 112 does not require that emissions that occur during periods of malfunction be factored into development of CAA section 112 standards.

Comment 24.2 : Two commenters (0146, 0153) were particularly concerned about the SSM issue and its relationship to com pliance using THC CEMS. The commenters (0146, 0153)24

- 107

stated that compliance determination while using THC CEMS should not include SSM events. The commenters (0146, 0153) added that with the emission limits based on stack test data which
did not include SSM events, it is not appropriate to include these periods when demonstrating compliance. The commenters (0146, 0153) contended that EPA must include provisions in the final rule to accommodate readings from continuous THC CEMS during SSM events for

purposes o f demonstrating compliance. Three commenters (0144, 0146, 0153) stated that a work practice standard for THC emissions during SSM events is appropriate. The commenters (0144, 0146, 0153) stated that it is nearly impossible to evaluate short term and widel y varying SSM emission spikes on a consistent basis and it is impractical to incorporate SSM events into testing. One commenter (0153) stated that facilities that have two thermal oxidizers venting to one stack may have significantly more
THC variations d ue to startups, shutdowns, and load shift events; therefore, these situations need to be properly accounted for in the final rule. The commenters (0144, 0146, 0153) added that elements of a work practice standard could include requirements to manage these events by operating the oxidizers according to manufacturer‘s recommendations, using internal procedures to minimize these SSM periods, conducting annual burner tune

- ups, and monitoring oxygen levels. Furthermore, the commenters (0144, 0146, 0153) stated t hat in the recently promulgated Boiler MACT, EPA removed the numerical emission limits from the affected sources during startups and shutdowns, and replaced them with work practices. The commenters (0144, 0146, 0153) respectfully requested that EPA be cons istent with other MACT standards in applying work practice standards for affected sources during startup and shutdown periods in lieu of
numerical emission limits. Two commenters (0146, 0153) suggested using a 99.9% UPL to calculate the THC
numerical limi ts to include more variability for SSM periods. This would be similar to the Boiler MACT treatment for highly variable CO levels. Response to comment 24. 2: We disagree with the commenters, and the rule remains unchanged. We note that the final rule does not require THC CEMS. PVC facilities have the option of demonstrating continuous compliance using CPMS or THC CEMS. As discussed in the preamble to the proposed rule, we determined that CAA section 112 does not require that emissions that occur during peri ods of malfunction be factored into development of CAA section
112 standards. With regard to startups and shutdowns, no information was provided to justify separate emission limitations for startups or shutdowns. Further, the commenters have not24

- 108

provided i nformation to support that the criteria in section 112(h) for setting a work practice standard have been satisfied. Pursuant to section 112(h), EPA may set a work practice standard if it is not feasible to prescribe or enforce an emission standard. Sectio n 112 (h) (2) provides that such a finding must be based on a determination that ―a hazardous air pollutant or pollutants cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant, or that any requirement for, or use of, such a conveyance would be inconsistent with any Federal, State or local law‖ or ―the application of measurement methodology to a particular class of sources is not practicable due to technological and economic limitations.‖ With regard to startups a nd shutdowns, no information was provided to justify separate emission limitations for startups or shutdowns. We note that source owners or operators who install CEMS or other continuous monitoring devices are required to operate them at all times. We beli eve that it is important to collect data during all process operating periods including periods of startup and shutdown and malfunction events. To the extent a CEMS records an exceedance during a period of startup or shutdown or a malfunction, and the owne r or operator believes the measurement was in error, the owner or operator can demonstrate using any available information that the source complied with the standard notwithstanding the CEMS measurement showing an exceedance. In any event, the commenters h ave not provided support for their assertions that it would be ―nearly impossible‖ to evaluate variable emissions concentrations during such periods of startup and shutdown or malfunction. While direct measurement of some factors may or may not take place during these periods, we are not persuaded that source owners or operators would be left with no means whatsoever to determine whether they remained in compliance during a period of startup, shutdown or malfunction. Source owner or operators may use other available means (including engineering judgment) or information to demonstrate that the source complied
with the standard. We disagree with the commenters who suggest using a 99.9, instead of 99, percent UPL for THC limits. Note that a 99 percent UPL repr esents the value which one could expect the
mean of a future 30

- run compliance test from the best performing 5 sources to fall below with 99 percent confidence; a 99.9 percent UPL would represent the value which one would expect the
mean of a future 30

- run compliance test from the best performing 5 sources to fall below with 99.9 percent confidence. With regard to the commenters‘ reference to variability approach adopted in another MACT rule, the EPA must select the approach most appropriate considering24

- 109

th e data set available to the agency for the particular emission source within the source category being regulated.

Comment 24. 3 : One commenter (0141) asserted that since the 1970s, when EPA began promulgating emission standards under the CAA‘s New Source P erformance Standards (NSPS) program, it determined that the standards did not apply during periods of startup, shutdown and malfunction (SSM). The commenter (0141) stated that the agency recognized that the technologies used to meet the NSPS often ―do not reach optimum operating efficiency for some time,‖ and that there is a ―statistical probability of infrequent, unavoidable mechanical failures‖ that can make it impossible for a source to meet the NSPS during a malfunction. [37 FR at 17214 (proposed Aug. 2 5, 1972).] Instead, the commenter (0141) contended that sources are required to follow ―good air pollution control practice for minimizing emissions‖ during periods of SSM, a standard that more accurately reflects the unique and unanticipated problems pres ented by diverse pieces of equipment during these events. The commenter (0141) added that as is well known, EPA used the NSPS program as a model for setting section 112 MACT standards in the early 1990s. The commenter (0141) stated that at the time, EPA st ated, with no equivocation, that "it is technically impossible to properly operate" some required pollution control techniques during "unpredicted and reasonably unavoidable failures of air pollution control systems." To address the simple and unavoidable fact that even MACT has limitations, the commenter (0141) stated that EPA exempted sources from having to meet the emission standards required to be met during normal operations and imposed a ―general duty‖ on sources to minimize any excess
emissions durin g periods of SSM. The commenter (0141) continued that in this PVC rulemaking, EPA proposes that the strict emission limits it has established for normal operations apply at all times, including periods of malfunction. The commenter (0141) stated that EPA r easons that it does not have to account for malfunctions in establishing emissions standards that must be met at all times because ―applying the concept of ―best performing‖ to a source that is malfunctioning presents significant difficulties.‖ 76 Fed. Reg . at 29556. The commenter (0141) added that while it is true that sources want to avoid malfunctions, since they can result in lost time, lost money, and potential harm to human health and the environment, EPA‘s simplistic declaration ignores
the fact that all control technologies have inherent limitations and that despite best efforts, sources may experience a malfunction. The commenter (0141 contended that EPA proposes to reverse a position the Agency has held for decades, without justification. The comm enter (0141)24

- 110

stated that if normal operation standards are to apply at all times, EPA must consider emissions experienced by best performing sources during a malfunction and adjust the standards accordingly. Alternatively, the commenter (0141) stated that EPA must promulgate a different standard under Section 112 to apply during a malfunction event. The commenter (0141) stated that EPA may promulgate a work practice standard under section 112(h). The commenter (0141) agreed that it would be ―impracticable‖ to take malfunctions into account in setting CAA section 112(d) standards for PVC production. The commenter (0141) added that it is often impossible to gather emission data during malfunctions. The commenter (0141) stated that there are work practices pres ently being used by sources

– such as regular maintenance of equipment and monitoring operating parameters to avoid a possible malfunction and stopping or cutting back the process accordingly

– that represent today‘s best practices to minimize excess emiss ions during a malfunction. The commenter (0141) stated that while the specific work practices employed by sources will depend on facility

- specific issues, such as process design, pollution control train, and other factors, they are nonetheless how best per forming sources would minimize excess emissions during a malfunction. Response to comment 24. 3: EPA has provided a detailed justification for its approach to malfunctions in the preamble to the proposed rule, and in the preamble to this final rule. As we explained, we recognize that even equipment that is properly designed and maintained can fail
and that such failure can cause an exceedance of the relevant emission standard. We are including an affirmative defense in the final rule as we have in other rec ent section 112 rules so as to balance the tension, inherent in many types of air regulation, to ensure adequate compliance while simultaneously recognizing that despite the most diligent of efforts, emission limits may be exceeded under circumstances beyo nd the control of the source. Mont. Sulphur & Chem. Co. v.
United States EPA, 2012 U.S. App. LEXIS 1056 (Jan 19, 2012) (rejecting argument that reliance on the affirmative defense was not adequate). EPA must establish emission standards that ―limit the q uantity, rate, or concentration of emissions of air pollutants on a continuous basis.‖ 42 U.S.C. § 7602(k)(defining ―emission limitation and emission standard‖). See generally Sierra
Club v. EPA , 551 F.3d 1019, 1021 (D.C. Cir. 2008) (emissions limitations under CAA section 112 must both continuously apply and meet section 112‘s minimum stringency requirements, even during periods of startup, shutdown and malfunction). Thus, we are required to ensure that
section 112 emissions limitations are continuous. As EPA explained in those preambles, the EPA has determined that CAA section 112 does not require that emissions that occur during24

- 111

periods of malfunction be factored into development of CAA section 112 standards. As the EPA further explained, accounting for malfunctions would be difficult, if not impossible, given the myriad different types of malfunctions that can occur across all sources in the category and given the difficulties associated with predicting or accounting for the frequency, degree, and durati on of various malfunctions that might occur. Setting work practice standards under section 112 presents the same issues as setting numerical emission limits given the varied nature of malfunctions. Thus EPA does not agree with commenter‘s suggestion that EPA apply work practices for malfunction events. Moreover, t he Federal Register notice cited by commenters is four decades old and does not reflect subsequent amendments to the Clean Air Act and court
decisions such as Sierra Club v. EPA . In any event, t he Federal Register notice merely stated EPA‘s preference at that time for adopting regulations in order to formalize an approach to excess emissions caused by malfunctions. EPA explained its view that such an approach was preferable to an informal enforce ment discretion approach for the following reasons: ―First, the existence of a formal process better informs the public of the policy and factual issues which will underlie enforcement of the standards. Second, affected industries which are making good

- fai th efforts to meet the standards will on the whole welcome a regularized means of informing the Agency in detail of the circumstances surrounding unavoidable emission excesses. Third, the Agency expects to benefit substantially from the information it will gain about the operation of the processes in question, for both future enforcement and standard setting.‖ 37 Fed. Reg. 17214,
17214

- 15 (Aug. 25, 1972). The affirmative defense is not an informal enforcement discretion approach of the type that EPA rejecte d in 1972 and provides the benefits associated with the formalized approach that EPA identified in its 1972 proposal. See Mont. Sulphur & Chem. Co. v.
United States EPA , 2012 U.S. App. LEXIS 1056 (5 th Cir. Jan 19, 2012)(in rejecting industry argument that reliance on the affirmative defense was not adequate, court stated ―[h]owever, here the EPA does not rely on enforcement discretion alone, but specifically promulgates an affirmative defense in the FIP, which clearly defines the requirements to avoid pena lties.‖).

Comment 24.4 : One commenter (0151) argued that EPA did not take all data into consideration. The commenter (0151) noted that he has incomplete data which were obtained while beginning to bring his greenfield plant on line. The commenter (0151) s tated that the data is for copolymer blending PVC resin, homopolymer blending resin, and dispersion resin and was provided in a separate attachment. He also noted the data values are above the current proposed25

- 112

standards. The commenter (0151) added that EPA should consider this information when evaluating the need for further subcategorization, revisions to the proposed stripped resin limits, and evaluations of emission limits that apply at all times, including periods of initial startup. Response to comment 24.4: We note that the data submitted were incomplete. The data also do not represent normal operation or operation during typical startup and shutdown activities, as it was collected during the beginning of a greenfield facility coming on line where

proc esses are being run for the first time. Consequently, the data were not used in the MACT floor analysis

. We evaluated the commenter‘s data and compared the data to the final limits for stripped resins. The data provided by the commenter show that the value s during startup are below or within a very small percentage of the final stripped resin limits for the three subcategories mentioned such that the limits should be achievable at all times and separate
standards are not warranted.



### 25.0 STATUTORY AUTHORITY

Co mment 25.1 : One commenter (0157) contended that S ection 1 1 2(d)(2) of the CAA dictates that EPA must consider cost when setting a new standard. The commenter further contended that the cost of the proposed rule is very high. Response to comment 25.1 : Sectio n 112(d)(2)

- (3) of t he Clean Air Act allows cost to be
considered only when analyzing options more stringent than the MACT floor level of control. This analysis was conducted for the proposed and final rules. The discussion of the beyond

- the

floor analysis is presented in section V.I of the preamble to the final PVC rules.

Comment 25.2 : One commenter (0150) contended that S ection 112(d)(6) of the CAA does not refer to the pre

- 1990 rules being vacated and replaced by the proposed rule

. The
commenter referre d to EPA‘s claim that their issuing new PVC rules in response to the vacatur of its previous unlawful ones is fulfilling EPA‘s obligation under 112(d)(6). The commenter (0150) explained that Section 112(d)(6), addresses the review and revision of existing §112(d) rules, and that because EPA‘s previous §112(d) rules were vacated, the rules EPA now proposes are not revisions but replacements for rules that, because of their illegality and vacatur, were
void ab initio. The commenter (0150) added that a lthough pre

- 1990 rules for PVC plants27

- 113

remained in effect following vacatur, those were not the §112(d) rules to which §112(d)(6)
refers. Response to comment 25.2 : The commenter has misinterpreted the discussion of our statutory authority. Under CAA section 112(d) (6), we are required to ―review, and revise as necessary (taking into account developments in practices, processes, and control technologies), emission standards promulgated under this section no less often than every 8 years.‖ In this rulemaking, we are fulfilling our obligation under CAA section 112(d)(6) to review and revise, as necessary, the PVC production area source standards, 40 CFR part 63, subpart DDDDDD,
which w ere not vacated.



### 26.0 SUBCATEGORIES

See Table 2

- 2 in this document for cross

- reference s in the preamble to the final PVC rules that discuss subcategories



### 27.0 VARIABILITY

Comment 27. 1 : One commenter (PH

- H

- 0002) stated that the agency‘s selection of emission points and evaluation of HAPs moves in the right direction. The commenter (PH

- H

0002) r ecommended that more consideration be given to the variety of emissions from a wide array of products that the industry manufactures. The commenter (PH

- H

- 0002) supported the selection of HAPs. Each resin can have a unique HAP profile and that should be tak en into
consideration. Response to comment 27. 1 : We acknowledge the commenter‘s support of the regulated pollutants. Selection of regulated pollutants is discussed in detail in preamble Section V.C.
Preamble Section V.D. also discusses revisions to subc ategorization since proposal which
address es the commenter‘s concern on variety of emissions from a wide array of products.

Comment 27. 2 : One commenter (PH

- BR

- 0009) encouraged EPA to examine the processes and look at the opportunities for flexibility an d variability, because there are sometimes differences in operations that can actually achieve an environmental benefit. There27

- 114

are differences in operations; and by allowing some flexibility, you may actually be able to improve the emissions' reduction. Th e commenter (PH

- BR

- 0009) supported the use of maximum achievable control technology. The commenter (PH

- BR

- 0009) stated that technology

- forcing standards will improve emissions and present them with a more competitive environment, especially if those standa rds are uniformly administered. The commenter (PH

- BR

- 0009) stated that as a result of competing in a world market, their products have to conform, not only to standards here, but to also satisfy the requirements of our competitors. Response to comment 27. 2 : See preamble Section V.F.5. for discussion on Emission Source Requirements applicable to resin stripping. In this preamble section, we discuss how additional flexibility is being provided by no longer requiring sources to comply with operating
limits an d conduct continuous parametric monitoring, and instead assuring compliance by requiring resin sampling. We acknowledge the commenter‘s support of our calculation of the
MACT floor limikts , and refer to preamble Section V.E.2 for further discussion on cha nges in
our database and the MACT floor emission limits since proposal.

Comment 27. 3 : One commenter (0146) stated that the agency has sought to incorporate variability in several of its rulemakings, but the only case to uphold an EPA variability analysis, coincidentally, involved the PVC MACT rule initially promulgated in 2002, which was vacated and remanded on other grounds by Mossville Envt‘l Action Now v. EPA, 370 F.3d 1232 (D.C. Cir. 2004). The commenter (0146) contended that i t is important to note th at the agency argued to the court that: in this case, determining the best five sources was impossible. The commenter (0146) added that t his is because of the great variability in RVCM emissions, and the fact that that variability is a result of the type o f resin being produced, not the technology or processes applied to control emission. The commenter (0146) stated that a ccording to EPA , there can even be great variability in RVCM emission at the same PVC plant, which would obviously employ
the same techno logy and processes on a day

- to

- day basis, if that plant produces a variety of
resins. The commenter (0146) added that w ith comparisons between plants impossible, and emission variations not related to technological performance, EPA claims it was unable to select the best five sources. Therefore, after considering other alternatives, the commenter (0146)
claimed that EPA determined that since all twenty

- eight PVC plants were subject to the part 61 NESHAP, those standards estimated the best five performing so urces. [Mossville Envt‘l Action Now v. EPA, 370 F.3d 1232, 1240 (D.C. Cir. 2004) (internal citations omitted)] The commenter27

- 115

(0146) concluded that t hese considerations remain true today, and despite the agency‘s best efforts, it is simply not possible to f it PVC homopolymers and copolymers into the commodity chemical paradigm of a simple and uniform product recipe process. Response to comment 27. 3 : See preamble Sections V.D. and V.E.2. for discussion on the topics presented in this comment, including subca tegorization based on resin types and variability. Section V.E.2. contains discussion on revisions to EPA‘s database and MACT floor calculations that address variability concerns. Section V.D. discusses revisions to subcategorization since proposal, includ ing separate subcategories for homopolymers and copolymers, with additional subdivisions for homopolymer resins.

Comment 27. 4 : One commenter (0146) supported the agency‘s efforts to account for variability in setting MACT floor limits, and in particular, use of the UPL for doing so. The commenter (0146) stated the agency notes in the preamble to the proposed rule ―[w]e account for variability of the best

- controlled source in setting floors, not only because variability is an element of performance, but be cause it is reasonable to assess best performance over time.‖ [76 FR 29544.] It is axiomatic that the Act requires facilities to comply 100% of the time with emissions limits that are based on the average level actually achieved by the five best performing
facilities. The commenter (0146) added that n o process is without variability, however, and the data used to determine the MACT compliance levels is only a snapshot in time, so there must be some way to account for variations in the process, products, etc

. Response to comment 27. 4 : We acknowledge the commenter‘s support of the MACT
floor determination , and refer to further discussion of the MACT floor calculation in preamble
Section V.E.2.

Comment 27. 5 : One commenter (0146) stated that EPA should apply a compliance averaging factor of 12 to properly estimate the future variability of monthly resin stripping limit
for TOHAP. The commenter (0146) stated that both the mass and concentration databases used by EPA to develop stripped resin limits for HAPs were populated with daily averages from each facility. The commenter (0146) stated that c ompliance requires that a 24

- hour average composite sample from each stripping column, or from each group of strippers processing the same resin type, be obtained each mon th. The commenter (0146) added that s ince compliance is based on
24

- hour composite samples (daily averages) and the database is populated with daily averages,27

- 116

there is no opportunity for averaging and the correct factor for m is 1. However, the commenter ( 0146) stated, after the first 13 months, compliance must be demonstrated based on a 12

- month rolling average concentration, calculated as the average of the 12 most recent 24

- hour arithmetic average concentrations. The commenter (0146) stated that b ecause the limit is then based on an average of 12 daily averages, the correct factor for m becomes 12 ; EPA set the number of future observations for the compliance average, the variable ― m ,‖ at 30. The commenter (0146) stated
that t his suggests that 30 samples w ill be used to meet the 12

- month rolling average, when in fact the average includes only 12 samples. The commenter (0146) concluded that the correct m factor
for use in this case is 12. Response to comment 27. 5 : See preamble Section V.E.2. for discussion o f MACT floor revisions, noting in particular revisions to the approach for stripped resins. Note especially that in
the final rule we removed the 12

- month rolling average compliance requirement

. In the final rule, compliance with the total non

- vinyl chlori de organic HAP limit for stripped resin is based
on a 24

- hour composite sample taken once per month and in the UPL calculation we used an m
value of 1.

Comment 27. 6 : Several commenters (0134, 0144, 0146) argued that EPA should apply a UPL of 99.9% to prop erly estimate the future variability of daily resin stripping limits for vinyl chloride, rather than the proposed 99% UPL. One commenter (0146) contended that agency‘s UPL analysis was performed on a data set consisting of a daily average. The commenter (0 146)
stated that t hese readings are to be assessed against a compliance frequency that also requires a daily average. The commenter (0146) added that a ccording to the agency‘s background documents, a 99% UPL means that ―one can be 99 percent confident that the reported level will fall below a MACT floor emission limit calculated using a UPL.‖ [Docket Document No. EPA

HQ

- OAR

- 2002

- 0037

- 100, at 4] The commenter (0146) concluded that it follows that a facility that is statistically able to meet a daily MACT flo or emission limit 99 percent of the time will be out of compliance once per every 100 samples. The commenter (0146) added that p ut another way, each of the five best performing facilities whose data was used to establish the MACT floor, would be expected t o be out of compliance once every 100 days, or multiple times per year. The commenter (0146) provided a chart on page 35 of their comments that summarizes vinyl chloride limits for suspension resin developed using four years of Method 107 compliance
data ; t he chart shows that application of the 99% percentile does not accurately demonstrate28

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emissions levels continuously achieved by the top performers. The commenter (0146) stated that further analysis of the data proves that on 52 days, members of the top 5 would be unable to meet
the limit ; in other words, on average, a top

- performing site would be out of compliance 2.6 days per year. The commenter (0146) argued that use of a 99% UPL does not comport with the D.C. Circuit‘s charge that the best performing f acility must meet the limit ―every day and under all operating conditions.‖ [PVC MACT Case, 370 F.3d at 1242] The commenter (0146) contended that direct application of the 99.9th percentile to the four year database be used to calculate the daily vinyl chl oride emission limit. One commenter (0144) noted that in recent proposed MACT standards like the Boiler MACT, EPA has used a 99.9% UPL to establish the corresponding MACT limit in order to duly account for the data variability. The commenter (0144) stated that

s ince the PVC manufacturers of suspension resins have traditionally made a wide variety of recipes with varying vinyl and HAP content, EPA should expand the confidence interval to 99.9% instead of the 99% currently used in the MACT floor UPL analysis to account for variability in a manner consistent with other recent MACT standards Response to comment 27. 6 : See preamble Section V.E.2. for discussion of MACT floor revisions, noting in particular revisions to the approach for stripped resins that address this comment. Note especially that in the final rule we used the 99.9 th percentile to determine variability because the 4

- year vinyl chloride emission data set for stripped resin was sufficiently large such that a UPL calculation was not appropriate.



### 28.0 CRO SS REFERENCES AND CITATIONS

Comment 28. 1 : One commenter (0146) provided a summary of citation and cross reference errors in Table 10 of the rule (Refer to Table 10 on page 11 of the comment letter). Response to comment 28. 1 : We thank the commenters for t heir input. The final rule incorporates commenter‘s edits and changes to citations and cross

- references where appropriate.

Comment 28. 2 : One commenter (0142) recommended revising section 63.11890(d)(6)(ii) for clarity. The commenter (0142) pointed out tha t, as written, this paragraph would seem to impose a reporting requirement that EPA likely did not intend. The commenter (0142) indicated that, taken literally, the paragraph seems to be saying that one would have a deviation from the PVC MACT standard any time there is a failure to comply with ―any‖ term in the facility29

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operating permit, even if the permit condition has nothing to do with PVC MACT. The

commenter (0142) recommended that, to correct this issue, section 63.11890(d)(6)(ii) read as follows: ―(i i) Any term or condition relating to compliance with this subpart that is included in the operating permit for any affected source required to obtain such a permit.‖ Response to comment 28. 2 : We agree with the commenter‘s suggestion. It is not our intent for non

- compliance with permit conditions other than those associated with the final PVC rules to trigger violations of the PVC MACT standards. We have revised the final rule based on
the commenter‘s suggestion.

Comment 28. 3 : Two commenters (0118 , 0152) r equested an extension to the comment period for the proposed rule. The commenters (0118, 0152 ) presented various reasons for this request, including, among others, the limited number of industry experts available to review the proposed rule and the number of supporting documents associated with the proposal. One commenter (0118) stated that the industry‘s review of the rule was hampered by missing information and late submissions to the docket. Specifically, the commenter (0118) stated that
six technical an alysis spreadsheets used for floor and beyond the floor calculations, were released late, depriving commenters of almost two weeks time to review the information. The commenters (0118) further contended that in other instances, not all of the steps or data used for specific MACT floor calculations were disclosed in the available background documents, making it difficult to respond to the appropriateness of a floor calculation. Response to comment 28. 3 : We granted an extension of the comment period for two weeks to afford additional time for review of the additional data that were added to the docket

.



### 29.0 DOCKET

Comment 29. 1 : One commenter (0118) argued that the docket contains little record of
EPA communications with stakeholders. The commenter (0118) argued that due to the litigation in Mossville Environmental Action Now v. EPA, there were likely multiple communications that could be relevant to commenters, and thus the agency should submit all unprotected documents and communications to the docket. In parti cular, the commenter 0118) identified one email document not included in the docket, which highlighted some of the key issues with the use of Method 8260B over Method 107 to sample stripped resins that are the basis of current concerns29

- 119

about the floor calc ulations. Because of these omissions, the commenter (0118) contended that EPA should provide commenters additional time for review once these documents are submitted. Response to comment 29. 1 : We disagree with the commenter‘s assertion.
C ommunications wit h stakeholders that have occurred on this project are included in the docket. The specific document referenced by the commenter is included. We granted an extension of the comment period for two weeks to address concerns about document availability.

Comme nt 29. 2 : Two commenters (0134, 0154) contended that the proposed rule contains technical issues and errors. One commenter (0134) argued that these mistakes occurred due to the accelerated timeline of the rulemaking process, but that through subsequent data submittals and clarification of existing data, EPA now has the data required to fix these errors and redevelop emissions limitations. Another commenter (0154) pointed out a specific data error in the Pedricktown plant dispersion resin concentration databa se. They stated an example from
12/5/09 that has the VCM concentration from the resin stripper transposed with the dried resin sample, and asked that these data points be removed from any calculation to avoid further error. One commenter (0153) stated that they would be providing corrected data, and may provide additional data in cases where there was insufficient time to generate the data previously (even after the comment period closes). Response to comment 29. 2 : We have reviewed all the data corrections submitted by industry , and where valid, we have incorporated them into the database and used them in subsequent analyses. See the supporting memorandum Updated Information Collection and Additional Data Received for the Polyvinyl Chloride and Copolymers ( PVC) Production Source Category for a discussion of how corrected data were evaluated.

Comment 29. 3 : One commenter (0153) requested that two letters discussing the classification of OCC‘s Deer Park facility as an area source be reviewed by EPA and added to the docket [(1) Letter from Barry Christensen, Oxy Vinyls, LP, to Jodi Howard, U.S. EPA, re: PVC and Copolymer MACT: Requirement to Provide Information Pursuant to Section 114 of the Clean Air Act (42 USC. §7414) (October 8, 2009); and (2) Letter from B arry Christensen, Oxy Vinyls, LP, to Jodi Howard, U.S. EPA, re: PVC and Copolymer MACT: Requirement to Provide Information Pursuant to Section 114 of the Clean Air Act (43 USC. §7414) (November 9, 2009)].31

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Response to comment 29. 3 : The two letters have bee n included in the docket.



### 30.0 INFORMATION GATHERING

See T able 2

- 2 of this document for discussion in the preamble related to information gathering.



### 31.0 STATUTORY AND EXECUTIVE ORDERS

Comment 31. 1 : One commenter (PH

- BR

- 0011) pointed out that EPA must address
Ex ecutive Order 13107, which mandates that EPA is responsible for ensuring implementation of ratified human rights treaties, which are applicable to environmental protection in the case of this proposed rule. Response to comment 31. 1 : The commenter has not explained how the referenced
Executive Order is relevant to this rulemaking or how it would lead to any modification of the
rule

.

Comment 31. 2 : One commenter (0126) raised a concern regarding EPA‘s implementation of Executive Order 12866, intended to redu ce regulatory burden on business.
The commenter (0126) argued that the proposed rule imposes a high cost with little benefit to public health. The commenter (0126) pointed out that while the American Chemistry Council (ACC) Vinyl Chloride Health Committee ( VCHC ) review of the proposed NESHAP for vinyl chloride focused on the protection of public health, EPA has produced no recent risk assessment related to potential impacts or benefits to public health or the effectiveness of existing regulations to protect public health from vinyl chloride emissions. The commenter (0126) expressed concern that EPA‘s proposal was, rather, based on current emissions data and modeling for storage vessels, equipment leaks, heat exchange systems, process vents, residual vinyl ch loride in stripped resins, and wastewater. The commenter (0126) noted that while the docket for this proposal contains an economic impact analysis, it also notes the absence of a recent risk assessment or any information related to potential impacts or ben efits to public health. The commenter (0126)31

- 121

stated that EPA produced no information on the effectiveness of existing regulations in protecting public health from vinyl chloride emissions. Response to comment 31. 2 : As required by EO 12866, we prepared an a nalysis of the potential costs and emissions impacts associated with the rule, which is available in the docket. We have also concluded that preparation for a risk assessment is not necessary for this rule.

Comment 31. 3 : Two commenters (PH

- BR

- 0004 , PH

- BR

- 0010) contended that EPA needs to more effectively address the issue of environmental justice raised by Executive Order
12898. The commenters (PH

- BR

- 0004, PH

- BR

- 0010) expressed concern that EPA‘s methodology for the proposed rule does not adequately prote ct public health, and that EPA
should establish maximum reduction s for each HAP emitted by the PVC industry to protect public health. One commenter (PH

- BR

- 0010) further argued that, to protect public health, EPA needs to establish ―emission limits for each of the known and probable carcinogen hazardous air pollutants emitted by the PVC production process.‖ The commenter PH

- BR

- 0010) argued that, under the executive order, EPA needs to evaluate and control the many accidental releases of HAPs to protect human health. Response to comment 31. 3 : This rule meets the technology

- based requirements of section 112 (d)(2) and (5) of the CAA, which base control requirements on what is achieved by the best

performing sources. After industries have the opportunity to com ply with these final rules, the agency will conduct a review to determine if there are unacceptable adverse health risks associated with the remaining emissions. At that time we will take appropriate action to address any unacceptable health risks. With re gard to accidental releases of HAPs to protect human health, we have addressed this issue in part by eliminating exemptions for pollutants emitted during startup, shutdown and malfunction events, and sources exceeding their emission limits during these eve nts must submit deviation reports and may be subject to enforcement action. In addition, the accidental release program under section 112 (r) of the Clean Air Act requires owners and operators of stationary sources to identify hazards, and prevent and mini mize the effects of accidental releases wherever extremely hazardous substances are present at their facility. This program is maintained by the states.

Comment 31. 4 : The commenters (PH

- BR

- 0004, PH

- BR

- 0010) contended that EPA should be addressing the envi ronmental justice issues of a state like Louisiana or a small32

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African

- American city like Mossville that is disproportionately exposed to HAPs from the PVC industry. One commenter (PH

- BR

- 0010) provided details about Mossville, such as the fact that it
is su rrounded by 14 facilities including the largest concentration of vinyl manufacturers in the U. S., as well as the fact that residents‘ blood levels of dioxin are three times higher than background blood levels in the United States. The commenter (PH

- BR

- 0010 ) referred to a study that has linked the particular dioxin compounds found in residents‘ blood with those emitted by the vinyl manufacturers. The commenter (PH

- BR

- 0010) argued that EPA‘s methodology of ―aggregation‖ in justifying its proposal under Execu tive Order 12898 is an attempt to obscure the fact that individual communities like Mossville should be protected under the Executive Order.
The commenter had never seen the proposed ―aggregation‖ approach to addressing Executive
Order 12898. Response to comment 31. 4 : This national rule is being adopted to meet the technology

based requirements of section 112(d)(2), which requires that emissions be controlled to levels achieved by the best

- performing sources in the category. As such, we believe that signif icant health protection is being accorded by the final rule. To the extent that commenters believe that there are threats posed by emissions from collections of different sources in any particular community, we encourage communities to work directly with t heir local and state governmental agencies to address their concerns.



### 32.0 NOTIFICATIONS, RECORDKEEPING, AND REPORTS

Comment 32. 1 : Two commenters (0142, 0153) stated that the certification statement is more detailed than necessary. The commenters (0142 and 0 153) stated that r ather than having seven individual certification statements, one general statement is appropriate. One commenter (0153) suggested, ―I hereby certify that the information given in this report, based on information
and belief formed after r easonable inquiry is true, accurate, and complete‖ and the other commenter (0142) suggested ―Any application form, report, or compliance certification submitted pursuant to these regulations shall contain certification by a responsible official of truth, a ccuracy, and completeness. The commenter (0142 stated that this certification and any other certification required under this part shall state that, based on information and belief formed after reasonable inquiry, the statements and information in the docu ment are true, accurate, and complete.‖32

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Response to comment 32. 1 : The Agency has established the elements needed for the compliance certification through previous experience implementing the section 112(d) provisions. We believe that providing the seven individual statements in a checklist type fashion ensure ease of review and completeness for both EPA and the regulated community that each
element is there and has been certified.

Comment 32. 2 : One commenter (0142) suggested the contents of the Notifica tion of Compliance status need not include information already submitted in test plans and test reports

. The commenter agreed that performance test results and operating parameters need to be included in the Notification, but to require a facility to inclu de performance test records with the Notification of Compliance Status is duplicative. This information is already required to be submitted in the test plan, test report, or EPA‘s WebFIRE database. The commenter cited rule language; §63.11985(a)(5) require s the inclusion of ―...one test report for each test method used for each process vent.‖ The commenter requested that EPA update §63.11985 to require submitting a summary of test results rather than requiring the submittal of the test report again.
One com menter (0142) stated the b atch precompliance report is not necessary as the information is similar to that included in the Notification of compliance status

. To avoid duplication, the commenter suggested it is only necessary to include information related to Engineering assessments with the Notification of compliance status as required by § 63.11985 (a)(5)(ii)(c). The commenter (0142) requested that §63.11985 be updated by deleting paragraph (c)(2), the batch precompliance report, and the reference to the B atch precompliance report in §63.11950(i). Response to comment 32. 2 : We disagree with the commenters‘ assertion that submitting test reports as a part of the Notification of Compliance Status report is duplicative. The test reports will contain informatio n, such as calibration records and raw data sheets for field sampling that would not be included with the test results and test plans but are necessary for our review. Furthermore, reports for test methods that are compatible must be submitted
electronica lly through the Electronic Reporting Tool (ERT)

. The batch precompliance report is different from the test reports required by the Notification of Compliance status report because it is required prior to conducting any tests. A facility must develop a report that will describe test conditions and other information that is used32

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to establish operating limits for all batch operations. The batch operations must then operate in
accordance with these established limits.

Comment 32. 3 : One commenter (0142) su ggested that Table 5 should be updated to show that §63.10(e)(2) does not apply

. The commenter (0142) pointed out that Table 5 indicates that §63.10(e)(2)(i) applies, but that §63.10(e)(2)(i) is for reporting the results of a CMS performance
evaluation as required under §63.8(e), and the table indicates that the provisions of §63.8(e) pertaining to the corresponding performance evaluation do not apply

. The commenter (0142) concluded that, since the CMS performance test does not apply, the reporting of resul ts must not apply either. Response to comment 32. 3 At proposal 63.8(e) was incorrectly not included in the General Provisions table (t able 5 in the proposed rule) . For the final rule, we have added the
citation back into the General Provisions table (now Table 4 in the final rule). Consequently, we are maintaining the requirement to comply with 63.10(e)(2).

Comment 32. 4 : One commenter (0142) contended that EPA‘s proposed requirement to submit copies of inspection records with the semiannual compliance rep orts is unreasonable. EPA proposed that inspection reports be included with required semiannual excess emissions and continuous monitoring system performance reports in §63.11985(b). The commenter (0142) continued that the rule also addressed reporting ove rlap with Title V reports in §63.11985(b)(10). The commenter (0142) stated that a ny excess emission or continuous monitoring system event would be reported as a deviation in a Title V report and per §63.11985(b)(10) would not need to be reported in duplica te in a semiannual compliance report required by § 63.10(e)(3). The commenter (0142) noted that Title V also requires annual certification of compliance by the responsible corporate official making the inclusion of records as a demonstration of compliance

u nnecessary. One commenter (0142) supported the proposal that information reported in the Title V semiannual reports not be duplicated in compliance reports required by this rule; §63.11985(c)(10). Response 32. 4 : We disagree that the requirement is unreaso nable. Inspection reports are required to be submitted when a deviation has occurred to provide us with the details of the
deviation.32

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Comment 32. 5 : One commenter (0142) noted the proposed rule requires reporting of the same information regarding proces s changes in two different reports. The commenter (0142)
stated that t he provisions specified in 40 CFR 63.11985 of the proposed rule require that process changes be included with the compliance report. The commenter (0142) added that t his requirement incl udes submitting changes in information previously submitted

. The commenter (0142) noted that the notification requirements in §63.9 (as referenced in Table 5 of the proposed rule) also require submitting a report of any changes to previously submitted info rmation. The

commenter (0142) recommended removing the requirement in §63.9(j) of the General Provisions by updating Table 5 of the proposed rule to indicate that these requirements do not apply. Response to comment 32. 5 : We agree with the commenter tha t since information regarding process changes is required under §63.11985(b)(4)(iii) compliance with §63.9(j) is duplicative and unnecessary. The final rule has been updated to reflect this change.

Comment 32. 6 : Two commenters (0142, 0146) opposed the re quirement in section 63.11985(c)(1) that an affected source would need to provide EPA with 30 days advance notice of any inspection required for equipment leaks, heat exchangers, and closed vent systems. The commenters (0142, 0146) pointed out that inspect ions occur continuously at facilities and to the extent that inspections are ―scheduled,‖ the schedule is generally expressed as a range of days to allow personnel to assure the process is running in a normal, safe and orderly manner prior to the
start of the inspection. The commenters (0142, 0146) requested that EPA remove this notification requirement for the equipment leak, heat exchange system, and closed vent provisions in section 63.11915 by removing the references to sections 63.11915, 63.11920, and 63.11930 because inspections are conducted on such a frequency (potentially multiple times during a single day) that notification is overly burdensome on EPA and on the regulated community. They (0142, 0146) requested that in the case EPA does not choose t o eliminate these section references, EPA provide clarification of the specific inspection requirements in these
three sections for which EPA needs to be notified. Response to comment 32. 6 : We agree with the commenters that the 30 day advance
notification is not appropriate for equipment leaks, heat exchangers, and closed vent systems as these equipment are monitored frequently as part of leak detection and repair programs. The final rule was revised accordingly. The final rule maintains the 30 day notice f or storage vessels,
similar to the requirement in other storage vessel standards, such as subpart WW. For storage32

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vessels, inspections are not as frequent as for the other emission sources and they can be scheduled allowing EPA a 30 day advance notice.

Co mment 32. 7 : One commenter (0153) stated that a great deal of the reporting involves
various forms of notifications of leaks and releases. The commenter (0153) stated that t he PVC industry already has extensive reporting of any unpermitted release of vinyl chloride greater than 1 pound which already requires reporting in less than 24 hours and duplicates the compliance reporting required in much of Section (b) of this proposed rule. The commenter (0153) added
that Title V deviation reporting already require s reporting of anything that constitutes a
deviation. The commenter (0153) added that a ll of the inspections required by this rule require some sort of notification to the regulating agency. However, the commenter (0153) stated that
neither state or local agencies nor regulated entities have the necessary resources to respond to these duplicative reporting and notification requirements. The commenter (0153) contended that
this was an ideal opportunity for the agency to compare these various reporting requir ements and simplify them so that uniformity exists and duplication is eliminated

. The commenter (0153) suggested a detailed comparison of the reporting that is required by the VCM NESHAPS, versus this proposed rule, Title V reporting requirements, the appl icable parts of the HON, and the NRC release reporting requirements. Response to comment 32. 7 : The final rule does require deviations to be reported. However, §63.11985(b)(10) addresses what a facility is required to do where an overlap with Title V repo rts exists. It states, ―information required by this subpart, which is submitted with a Title V period report, does not need to be included in a subsequent compliance report required by this subpart or subpart referenced in the compliance report required b y this subpart.‖ The title V report must be referenced in the compliance report required by this subpart.

Comment 32. 8 : One commenter (0153) stated that many of the requirements that are
cross referenced to various sections of the HON rules are not clear

. The commenter (0153) noted
that the Other Control Device reporting section references 40 CFR 63.146 and says they must include any applicable information required by this section of the HON rules. The commenter (0153) stated that t his section of the HON rule refers to part 138 and 139 requirements. The commenter (0153) contended that i t is nearly impossible to figure out and be certain of what sections of the HON rule apply to PVC plants. The commenter (0153) recommended that a table,32

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similar to Table 5, cross referencing the specific sections that apply in the PVC MACT rule should be supplied by EPA and would be a great help to the regulated facilities. The commenter (0153) requested that o ne specific question needing clarification is whether a design eva luation is needed for wastewater strippers ; m ore explanation of that requirement is needed in the preamble and cost estimates, if it is required. Response to comment 32. 8 : The requirements for wastewater to comply with the Table 9
HAP listed in the HON ha ve been removed from the final rule.

Comment 32. 9 : Two commenters ( 0 121, PH

- BR

- 0010) contended that additional records are necessary. One commenter ( 0 121) stated that in addition to the recordkeeping requirements in 40 CFR part 63 subpart UU, the proposed rule be revised such that the source shall maintain records of the following: (a) the concentration and emission rate at the time that the leak is detected and (b) the stream composition of the stream where a leak has been detected. One commenter (PH

- BR

- 0 010) noted those requirements for the discharges in the proposed rule must be extended to violations associated with bypasses, pressure vessels and closed vent systems in
vacuum service. The commenter (PH

- BR

- 0010) stated that t hese records and reports are critical to determine emission concentrations and to determine the extent of impacts due to the emissions and measures that should be taken to prevent the reoccurrence of similar types of events. The commenter (PH

- BR

- 0010) added that t hese records are also critical to providing information to
the fence line communities. Response to comment 32. 9 : The emissions resulting from leaking equipment are required to be reported in the annual Title V report. Each facility has to characterize their streams and keep records of the emission profiles as specified in the final rule

. We are requiring recordkeeping under 40 CFR part 63, subpart UU and w e believe that these requirements are sufficient to determine compliance with the work practices set forth under this rule

. In the final rule, a ny discharges directly to the atmosphere from closed vent systems in vacuum service, pressure vessel closure devices, and bypass es (e.g. diverting a vent stream in HAP service away from the control device) are violations and must be r eported as deviations in the semi

- annual compliance report.

Comment 32. 1 0 : One commenter ( 0153) stated that §63.11985 (a)(7)(ii) indicates that sources must provide results of initial testing including annual average concentrations of VCM33

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and annual ave rage flow rate and concentration of total HAP listed on Table 9 of s ubpart G, and that §63.11985 (a)(7)(iii) indicates sources must provide analytical bac kup information for Table
9 of s ubpart G. The commenter (0153) argued that both of these requests are confusing and do not relate to what is required by the rule section dealing with initial and continuous requirements for stripped resin in Section 63.11960. Response to comment 32. 1 0 : These requirements are no longer in the final rule.



### 33.0 MISCELLANEOUS

Com ment 33. 1 : One commenter (0153) stated that engineering judgment must be applied

to interpret survey and test data. Response to comment 33. 1 : We have evaluated the available data using engineering and professional judgment to the best of our ability in fo rmulating this action.

Comment 33. 2 : One commenter (PH

- BR

- 0009) encouraged EPA to visit facilities to help determine the most reasonable rules and regulations for operation. Response to comment 33. 2 : We thank the commenters for their suggestion. We have conducted many site visits and collected information in support of the final rules.

Comment 33. 3 : One commenter (0144) submitted a correction of information submitted
for LDAR MACT Floor. The commenter (0144) stated that i ndication that compliance had be en achieved with 40 CFR part 63 subpart UU program at the Freeport site was erroneous, and the site was instead following 40 CFR part 61 subpart V. The commenter (0144) added that b ased on the correction, the commenter (0144) requested that cost and HAP re duction aspects of the established MACT floor be revised, in addition to information contained in Table 6

- 2 of the
docketed file EPA

- HQ

- OAR

- 2002

- 0037

- 0102. Response to comment 33. 3 : The commenter ‘ s corrections were included in the database,
and the MACT f

loor determination was revised accordingly. See the preamble for the final rules for a discussion of the revised MACT floor analysis and documented in the technical memorandum, Revised MACT Analysis for the Polyvinyl Chloride and Copolymers (PVC)
Productio n Source Category, which is available in the docket.33

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Comment 33.4 : One commenter (0153) supported the recognition in sections 63.11890(c)(1) and (7) that monitors must be allowed some downtime for maintenance and repairs, whether scheduled or not. If the monitors are well operated and maintained, quality assurance activities and repairs should not constitute deviations. Response to comment 33.4 : We thank the commenter for their support.

Comment 33.5 : One commenter (0153) requested flexibility in the final rule for determining operating parameter deviations. Proposed section 63.11890(d)(1) indicates that any exceedance of an operating parameter constitutes a deviation. The commenter argued that, from a practical and environmental standpoint, treating one ex ceedance of an operating parameter as a deviation is fundamentally wrong. The commenter (0153) pointed out that control equipment often has several operating parameters that can indicate proper operation, and if one of the monitors becomes inoperative, it does not necessarily indicate that excess emissions have occurred. The commenter (0153) requested that EPA include in the final rule a provision that allows an operator to demonstrate that no excess emissions have occurred by relying on the other
monitorin g parameters of operational performance even if one parametric monitor or emission monitoring device is not functioning as designed. The commenter (0153) provided an example: if a scrubber pH monitor is under repair, a site should be able to use manual rea dings to verify proper operation without incurring reportable deviations or an automatic presumption of an emissions violation. The commenter (0153) added that this revision is necessary because in some states, any deviation results in an automatic penalty assessment. Response to comment 33.5: While we agree with the commenter that a deviation does not necessarily constitute a violation, we disagree with the commenter's assertion that the rule needs additional flexibility regarding an operating parameter de viation. As the rule allows owners and operators the ability to request and, upon approval, use alternative monitoring approaches and alternative parameters (see section 63.11985(c)(5) and (6)), an owner or operator who is concerned about the ability of h is equipment to provide continuous monitoring can already submit a request to rely on an alternative monitoring approach or parameter in the event his equipment failed to operate properly.