United States Office of Air Quality EPA-453/C-99-001
Environmental Protection Planning and Standards May 1999
Agency Research Triangle Park, NC 27711
NATIONAL EMISSION STANDARDS FOR
HAZARDOUS AIR POLLUTANTS
(NESHAP): GENERIC MACT
BACKGROUND INFORMATION FOR
ACETAL RESINS, ACRYLIC AND
MOD ACRYLIC FIBER, HYDROGEN
FLUORIDE, AND POLYCARBONATE
PRODUCTION FINAL RULE
SUMMARY OF PUBLIC COMMENTS AND RESPONSES
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EPA-453/C-99-001
NATIONAL EMISSION STANDARDS FOR
HAZARDOUS AIR POLLUTANTS (NESHAP) FOR THE
ACETAL RESINS, ACRYLIC AND MODACRYLIC FIBER, HYDROGEN FLUORIDE,
AND POLYCARBONATE PRODUCTION SOURCE CATEGORIES
Background Information for
Promulgated Standards - Summary of
Public Comments and Responses
Emission Standards Division
U. S. Environmental Protection Agency
Office of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, NC 27711
May 1999
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Disclaimer
This report is issued by the Office of Air Quality Planning
and Standards, U. S. Environmental Protection Agency. Mention of
trade names and/or commercial products is not intended to
constitute endorsement or recommendation for use. Copies of this
report are available free of charge to Federal employees, current
contractors and grantees, and nonprofit organizations (as
supplies permit) from the Library Services Office (MD-35), U. S.
Environmental Protection Agency, Research Triangle Park, NC
27711, (919-541-2777) or, for a nominal fee, from the National
Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161, (703-487-4650).
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IV
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ENVIRONMENTAL PROTECTION AGENCY
Promulgation Background Information Document
National Emission Standards 'for Hazardous 'Air Pollutants (NESHAP)
for the
Acetal Resins, Acrylic and Modacrylic Fiber, Hydrogen Fluoride,
and Polycarbonate Production Source Categories
1. The EPA's final standards for acetal resins, acrylic and
modacrylic fiber, hydrogen fluoride, and polycarbonate
production under the generic MACT rule maintain current
industrial control levels and their subsequent reduction of
emissions of a number 'of hazardous air pollutants. The
hazardous air pollutants controlled by the final standards
under the generic MACT rule are associated with a variety of
adverse health effects including chronic health disorders
(e.g., cancer, structural changes of the lung), and acute
health disorders (e.g., dyspnea (difficulty in breathing),
and neurotoxic effects).
2. Copies of this document are available from the Internet at
http://www.epa.gov/ttn/oarpg/ramain.html or from the U.S.
Environmental Protection Agency Library (MD-35), Research .
Triangle Park, North Carolina 27711, telephone (919) 541-
2777.
3. For additional information contact:
Mr. David Markwordt
U.S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
Telephone: (919) 541-0837
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VI
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TABLE OF CONTENTS
1.0 SUMMARY 1-1
1.1 SUMMARY OF CHANGES SINCE PROPOSAL 1-1
1.2 SUMMARY OF IMPACTS OF PROMULGATED REGULATIONS . . . 1-2
2.0 OVERVIEW OF PUBLIC COMMENTS 2-1
2.1 ORGANIZATION OF COMMENT SUMMARIES 2-1
2.2 LIST OF ACRONYMS AND ABBREVIATIONS FOR UNITS OF MEASURE
2-7
3.0 GENERIC MAXIMUM ACHIEVABLE CONTROL TECHNOLOGY PREAMBLE . 3-1
3.1 GENERIC MACT APPROACH 3-1
3.2 COMMON CONTROL REQUIREMENT SUBPARTS 3-5
3.3 OTHER COMMENTS 3-6
4.0 NATIONAL EMISSION STANDARDS FOR CLOSED VENT SYSTEMS, CONTROL
DEVICES, RECOVERY DEVICES AND ROUTING TO A FUEL GAS SYSTEM
OR A PROCESS (40 CFR Part 63, Subpart SS) 4-1
4.1 GENERAL 4-1
4.1.1 Cross-referencing, Grammatical, and
Typographical Comments 4-1
4.1.2 Structure of the Regulation 4-2
4.2 DEFINITIONS 4-5
4.2.1 Fuel gas system 4-5
4.2.2 Transfer Racks 4-6
4.2..3 ' Control Device 4-6
4.2.4 Temperature Monitoring Device 4-8
4.2.5 Add and Delete Definitions 4-9
4.3 REQUIREMENTS 4-9
4.3.1 Recovery Devices 4-9
4.3.2 Transfer Racks 4-13
4.4 CLOSED VENT SYSTEMS 4-13
4.4.1 Requirements 4-13
4.4.2 Inspection Procedures 4-15
4.4.3 Leak Repair 4-16
4.5 NONFLARE CONTROL DEVICES USED TO CONTROL EMISSIONS FROM
STORAGE VESSELS AND LOW THROUGHPUT TRANSFER RACKS
4-16
4.5.1 Requirements 4-16
4.5.2 Performance Testing and Design Evaluation
Requirements 4-17
4.5.3 Monitoring Requirements 4-20
4.6 FLARE REQUIREMENTS 4-20
4.6.1 Requirements 4-20
4.6.2 Compliance Assessment 4-21
4.6.3 Monitoring Requirements 4-22
4.7 INCINERATORS, BOILERS, AND PROCESS HEATERS . . . 4-22
4.8 ABSORBERS, CONDENSERS, AND CARBON ADSORBERS USED AS
CONTROL DEVICES 4-23
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4.8.1 Requirements 4-23
4.8.2 Monitoring Requirements 4-24
4.9 ABSORBERS, CONDENSERS, AND CARBON ADSORBERS AND OTHER
RECOVERY DEVICES USED AS FINAL RECOVERY DEVICES . 4-24
4.9.1 Performance Test Requirements 4-24
4.9.2 Monitoring Requirements 4-26
4.10 HALOGEN SCRUBBERS AND OTHER HALOGEN REDUCTION DEVICES
4-27
4.10.1 General 4-27
4.10.2 Monitoring Requirements 4-27
4.11 GENERAL MONITORING REQUIREMENTS FOR CONTROL AND
RECOVERY DEVICES 4-27
4.11.1 Alternative Monitoring Requirements . . 4-27
4.11.2 Backup Monitoring Equipment 4-28
4.11.3 Operation and Maintenance of CPMS . . . 4-28
4.'12 PERFORMANCE TEST AND COMPLIANCE ASSESSMENT REQUIREMENT
FOR CONTROL DEVICES 4-30
4.13 RECORDKEEPING REQUIREMENTS 4-30
4.13.1 Performance Test Records 4-30
4.13.2 Continuous Monitoring Records 4-31
4.13.3 Control and Recovery Device Monitoring
Records 4-34
4.13.4 Storage Vessel Records 4-3,8
4.13.5 Start-up . Shutdown, and Malfunction Records
4-38
4.13.6 3-Hour Averaging 4-39
4.13.7 Absorber Specific Gravity Monitoring . 4-40
4.14 REPORTING REQUIREMENTS 4-41
4.14.1 Compliance Assessment Reports 4-41
4.14.2 Control Device Monitoring Reports . . . 4-43
0 NATIONAL EMISSION STANDARDS FOR EQUIPMENT LEAKS - CONTROL
LEVEL 1 (40 CFR PART 63, SUBPART TT) 5-1
5.1 DEFINITIONS 5-1
5.2 COMPLIANCE DETERMINATION 5-1
5.3 EQUIPMENT IDENTIFICATION 5-1
5.4 LEAK REPAIR ' 5-3
5.5 VALVES IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE 5-5
5.6 PUMPS IN LIGHT LIQUID SERVICE 5-5
5.7 ENCLOSED-VENTED PROCESS UNITS 5-6
5.8 GENERAL 5-6
5.8.1 Applicability 5-7
5.8.2 Definitions 5-8
5.8.3 Compliance assessment 5-8
5.8.4 Equipment Identification 5-10
5.8.5 Instrument and Sensory Monitoring for Leaks
5-11
5.8.6 Leak Repair 5-14
5.8.7 Valves in Gas and Vapor Service and in Light
Liguid Service Standards 5-15
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5.8.8 Pumps in Light Liquid Service Standards
5-17
5.8.9 Connectors in Gas and Vapor Service and in
Light Liquid Service Standards .... 5-19
5.8.10 Agitators in Gas and Vapor Service and in
Light Liquid Service 5-20
5.8.11 Compressor Standards 5-20
5.8.12 Sampling Connection Systems Standards . 5-21
5.8.13 Closed Vent Systems and Control Devices; or
Emissions Routed to a Fuel Gas System or
Process Standards 5-21
5.8.14 Recordkeepinq Requirements 5-23
5.8.15 Reporting Requirements 5-23
6.0 NATIONAL EMISSION STANDARDS FOR EQUIPMENT LEAKS - CONTROL
LEVEL 2 (40 CFR PART 63, SUBPART UU) 6-1
6.1 GENERAL COMMENTS 6-1
6.2 APPLICABILITY 6-2
6.3 ALTERNATIVE MEANS OF EMISSION LIMITATION 6-2
6.4 EQUIPMENT IDENTIFICATION 6-2
6.5 LEAK REPAIR 6-3
6.6 VALVES IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE 6-3
6.7 PUMPS IN LIGHT LIQUID SERVICE 6-5
6.7.1 Calculation of PL and PT 6-5
6.7.2 Sealless Pumps 6-6
6.8 CONNECTORS IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE 6-7
6.9 PUMPS, VALVES, CONNECTORS, AND AGITATORS IN HEAVY
LIQUID SERVICE 6-9
6.10 QUALITY IMPROVEMENT PROGRAM FOR PUMPS 6-9
6.11 ENCLOSED VENTED PROCESS UNITS OR AFFECTED FACILITIES
6-11
6.12 REPORTING REQUIREMENTS 6-11
6.13 OTHER COMMENTS 6-13
6.13.1 General Comments 6-13
6.13.2 Applicability 6-15
6.13.3 Definitions 6-16
6.13.4 Equipment Identification 6-17
6.13.5 Instrument and Sensory Monitoring for Leaks
6-18
6.13.6 Leak Repair 6-21
6.13.7 Valves in Gas and Vapor Service and in Light
Liquid Service Standards 6-22
6.13.8 Pumps in Light Liquid Service Standards
6-24
6.13.9 Connectors in Gas and Vapor Service and in
Light Liquid Service Standards .... 6-25
6.13.10 Agitators in Gas and Vapor Service and in
Light Liquid Service Standards .... 6-26
6.13.11 Pumps, Valves, Connectors, and Agitators in
Heavy Liquid Service; Pressure Relief Devices
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in Liquid Service; and Instrumentation
Systems Standards 6-26
6.13.12 Sampling Connection Systems Standards . 6-26
6.13.13 Closed Vent Systems and Control Devices; or
Emissions Routed to a Fuel Gas System or
Process Systems 6-27
6.13.14 Quality Improvement Program for Pumps . 6-28
6.13.15 Alternative Means of Emission Limitation:
Batch Processes 6-29
6.13.16 .Recordkeepinq Requirements 6-30
7.0 NATIONAL EMISSION STANDARDS FOR STORAGE VESSELS (TANKS) -
CONTROL LEVEL 2 (40 CFR PART 63, SUBPART WW) 7-1
7.1 GENERAL COMMENTS 7-1
7.2 APPLICABILITY 7-1
7.3 DEFINITIONS . . 7-2
7.4 STORAGE VESSEL CONTROL REQUIREMENTS 7-4
7.5 FLOATING ROOF REQUIREMENTS 7-5
7.6 PRESSURIZED STORAGE VESSEL REQUIREMENTS 7-13
7.7 PROCEDURE FOR DETERMINING NO DETECTABLE EMISSIONS
7-13
7.8 RECORDKEEPING REQUIREMENTS 7-14
7.9 REPORTING REQUIREMENTS 7-15
8.0 GENERIC MACT STANDARDS (40 CFR PART 63, SUBPART YY) . . 8-1
8.1 APPLICABILITY 8-1
8.1.1 Flexible Operation Units 8-1
8.1.2 Coordination/Overlap With Other Rules . . 8-3
8.2 DEFINITIONS 8-5
8.2.1 General Provisions and the Act 8-5
8.2.2 Closed Vent System 8-5
8.2.3 Equipment 8-5
8.2.4 Flexible Operations 8-6
8.2.5 Subsequent Startup 8-6
8.2.6 Process Vent 8-7
8.2.7 Process Unit Shutdown 8-8
8.2.8 Recovery Device 8-9
8.2.9 Transfer Rack 8-9
8.2.10 Add Definitions 8-10
8.3 COMPLIANCE SCHEDULE 8-11
8.4 SOURCE CATEGORY-SPECIFIC APPLICABILITY, DEFINITIONS,
AND REQUIREMENTS 8-12
8.4.1 Acrylic and Modacrvlic Fiber Production
8-12
8.4.2 Hydrogen Fluoride Production ..... 8-13
8.4.3 Polycarbonate Production 8-22
8.5 PROCESS VENTS FROM CONTINUOUS UNIT OPERATIONS;
APPLICABILITY DETERMINATION PROCEDURES AND METHODS
. 8-27
8.5.1 Repropose §63.1104 8-29
8.5.2 Batch Unit Operations 8-29
8.5.3 Test Method 26 or 26A 8-30
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8.5.4 Low HAP Concentration Exclusion .... 8-31
8.5.5 Process Changes 8-31
8.5.6 Opt-in Language 8-32
8.6 CROSS-REFERENCE, FORMAT AND GRAMMATICAL COMMENTS 8-33
8.7 COMPLIANCE WITH STANDARDS AND OPERATION AND MAINTENANCE
REQUIREMENTS 8-56
8.7.1 Shutdown of Continuous Monitoring System
8-56
8.7.2 Excursion/Violation 8-57
8.7.3 Credible Evidence 8-58
8.8 RECORDKEEPING REQUIREMENTS 8-59
8.8.1 On-Site Data Retention 8-59
8.8.2 Recordkeeping Summary Tables 8-60
8.8.3 Report Retention 8-60
8.9 REPORTING REQUIREMENTS 8-61
8.9.1 Notice of Initial Startup 8-61
8.9.2 Notification of Compliance Status . . . 8-61
8.9.3 Periodic Report 8-61
8.9.4 Reporting Requirement Summary Tables . 8-62
8.9.5 Implementation Schedule 8-62
8.9.6 Request for an Adjustment to Time Period or
Postmark Deadline 8-63
8.10 STARTUP, SHUTDOWN, AND MALFUNCTION 8-64
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1. 0 SUMMARY
On October 14, 1999, the U. S. Environmental Protection
Agency (EPA) proposed national emission standards for hazardous
air pollutants (NESHAP) for the acetal resins production, acrylic
and modacrylic fiber production, hydrogen fluoride production,
and polycarbonate production source categories (63 FR 55178)
under authority of Section 112 of the Clean Air Act (Act).
Twenty-one public comment letters were submitted to the generic
MACT docket, inclusive of the items submitted to the separate
dockets established for each of the source categories proposed to
be regulated. Some of the comment letters received are
duplicates. At proposal, the EPA requested that commenters
submit source category-specific comments to dockets established
for each of the generic MACT source categories for which
requirements were proposed and general nonsource category-
specific comments to the generic MACT docket. This request meant
that some comment letters were submitted to both the nonsource
category-specific generic MACT docket and one or more of the
generic MACT source category-specific dockets.
The comments that were submitted and the responses to these
comments are summarized in this document. This summary is the
basis for the revisions made to the standards between proposal
and promulgation.
1.1 SUMMARY OF CHANGES SINCE PROPOSAL
Numerous changes have been made since the proposal of these
standards. Major changes include amendments to the acrylic and
modacrylic fiber control requirements applicability for solution
process spinning operations; grammatical and structural
improvements; clarifications; and removal of provisions for
process vents from batch unit operations.
1.2 SUMMARY OF IMPACTS OF PROMULGATED REGULATIONS
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The impacts resulting from the promulgated standards for the
source categories (i.e., AR production, AMF production, HF
production, and PC production) are determined relative to the
baseline that is set at the level of control in absence of the
rule. The emissions reductions associated with the application
of the control or recovery devices for the regulated source
categories are expected to be small as the AR, AMF, HF, and PC
production facilities affected by this rule essentially already
have a level of control equivalent to that determined to be MACT.
Based on previous impacts analyses associated with the
application of the control and recovery devices required under
the standards and because each of the four regulated source
categories have only five or fewer major sources, we believe that
there will be minimal, if any, adverse environmental or energy
impacts associated with the final standards. ,/
Likewise, based on available information, we estimate that
the cost and economic impacts of the final standards for the four—
source categories being regulated will be insignificant or *
minimal. The economic analyses for each of the four source
categories can be obtained from the dockets established for these ••••
source categories.
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2.0 OVERVIEW OF PUBLIC COMMENTS
The public comment period following the October 14, 1998
Federal Register notice (proposed rule) lasted from October 14,
1998 to January 12, 1999. Late comments received after
January 12, 1999 were also accepted. A total of 21 letters were
submitted and have been placed in the dockets established for
this rulemaking. Table 2-1 presents a listing of all persons
submitting written comments, their affiliations, and the recorded
docket item number assigned to their correspondences.
2.1 ORGANIZATION OF COMMENT SUMMARIES
For the purpose of orderly presentation, the comments
have been categorized under the following topics:
• preamble comments,
• comments received on 40 CFR part 63, subpart SS,
• comments received on 40 CFR part 63, subpart TT,
• comments received on 40 CFR part 63, subpart UU,
• comments received on 40 CFR part 63, subpart WW, and
• comments received on 40 CFR part 63, subpart YY.
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TABLE 2-1.
LIST OF COMMENTERS ON PROPOSED NATIONAL EMISSION
STANDARDS FOR HAZARDOUS AIR POLLUTANTS
Docket number
Commenter and affiliation
A-97-16a, IV-D-01
Mr. Alphonse McMahon
Counsel-Environmental, Health and Safety
Programs
General Electric Company
One Lexan Lane
Mount Vernon, Indiana 47620
A-97-16, IV-G-01
Mr. Steve Knis
Technical Specialist-Air Expertise Center
The Dow Chemical Company
2301 North Brazosport Blvd.
Freeport, Texas 77541-3257
A-97-17, IV-D-01
Mr. John W. Webster
Manager Regulatory Affairs
Devro-Teepak, Inc. .
915 North Michigan
Danville, Illinois 61832
A-97-17b, IV-D-02
Ms. Karin Ritter
Senior Regulatory Analyst
American Petroleum Institute
1220 L Street, Northwest
Washington, DC 20005-4070
A-97-17, IV-D-03
Ms. Rasma I. Zvaners
Senior Manager
Environmental Policy
Chemical Manufacturers Association
1300 Wilson Blvd.
Arlington, Virginia 22209
A-97-17, IV-D-04
Mr. D.R. Cheuvront
Site HSE Leader
Allied Signal Inc.
Fluorine Products
P.O. Box 226
Geismar, LA 70734
A-97-17, IV-D-05
Mr. Raymond P. Berube
Acting Director
Office of Environmental Policy and
Assistance
Department of Energy
Washington, DC 20585
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Docket number
Commenter and affiliation
A-97-17, IV-D-06
Mr. James T. Holcombe
Senior Environmental Engineer
Environmental Planning
Mail Code B24A
Post Office Box 7640
San Francisco, CA 94120
A-97-17, IV-D-07
Mr. Brian L. Taranto
Safety and Environmental Affairs
Exxon Chemical
Post Office Box 3272
Houston, Texas 77253-3272
A-97-17, IV-D-08
Mr. Alphonse McMahon
Counsel-Environmental, Health and Safety
Programs
General Electric Company
One Lexan Lane
Mount Vernon, Indiana 47620
A-97-17, IV-G-01
Ms. Liane Platt
EH&S Regulatory Management Expertise
Center
The Dow Chemical Company
2301 N. Bazosport Blvd.
Freeport, Texas 77541-3257
A-97-17, IV-G-02
Mr. John Prokop
President and Counsel
Independent Liquid Terminals Association
133 15cn Street, N.W.
Suite 650
Washington, DC 20005
A-97-17, IV-G-03
Ms. Alice E. Boomhower
Regulatory Services Coordinator
Amoco Corporation
Environmental, Health and Safety
28100 Torch Parkway, Suite 500
Warrenville, Illinois 60555-4015
A-97-17, IV-G-04
Mr. Steve Knis
Technical Specialist-Air Expertise Center
The Dow Chemical Company
2301 North Brazosport Blvd.
Freeport, Texas 77541-3257
A-97-17, IV-G-05
Mr. Steve Knis
Technical Specialist-Air Expertise Center
The Dow Chemical Company
2301 North Brazosport Blvd.
Freeport, Texas 77541-3257
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Docket number
Commenter and affiliation
A-97-17, IV-G-06
Mr. Edward J. Campobenedetto
Deputy Director
Institute of Clean Air Companies
1660 L Street NW
Suite 1100
Washington, DC 20036-5603
A-97-17, IV-G-07
Ms. Liane Platt
EH&S Regulatory Management
The Dow Chemical Company
2301 North Brazosport Blvd.
Freeport, Texas 77541-3257
A-97-17, IV-F-01
Public Hearing in the Matter of:
40 CFR Part 63, National Emission
Standards for Hazardous Air Pollutants:
Generic Maximum Achievable Control
Technology. Transcript of Hearing held
in the ERC Auditorium, Research Triangle
Park, North Carolina. November 25, 1998.
A-97-18C, IV-D-01
Mr. Alphonse McMahon
Counsel-Environmental, Health and Safety
Programs
General Electric Company
One Lexan Lane
Mount Vernon, Indiana 47620
A-97-18, IV-D-02
Mr. David S. Krawczyk
Manager, Environmental Protection
Solutia
Applied Chemistry, Creative Solutions
A-97-18, IV-G-01
Ms. Alice E. Boomhower
Regulatory Services Coordinator
Amoco Corporation
Environmental, Health and Safety
28100 Torch Parkway, Suite 500
Warrenville, Illinois 60555-4015
A-97-18, IV-F-01
Public Hearing in the Matter of:
40 CFR Part 63, National Emission
Standards for Hazardous Air Pollutants:
Generic Maximum Achievable Control
Technology. Transcript of Hearing held
in the ERC Auditorium, Research Triangle
Park, North Carolina. November 25, 1998,
2-5
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Docket number
Commenter and affiliation
A-97-19d, IV-D-01
Mr. Alphonse McMahon
Counsel-Environmental, Health and Safety
Programs
General Electric Company
One Lexan Lane
Mnnnf V^rnnn . TnrHpna 47fi?D
3- Polycarbonate production generic MACT source category-
specific docket.
b Generic MACT nonsource category-specific docket.
c Acrylic and modacrylic fiber production source
category-specific docket.
d Acetal resins production source category-specific
docket.
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2.2 LIST OF ACRONYMS AND ABBREVIATIONS FOR UNITS OF MEASURE
ACRONYMS
Act Clean Air Act
Administrator
EPA Administrator
AMF acrylic and modacrylic fiber
AR acetal resins
CAA Clean Air Act
CAR Consolidated Air Rule
CEMS Continuous emissions monitoring system
CFR Code of Federal Regulations
CPMS Continuous parameter monitoring system
EPA U. S. Environmental Protection Agency
FR Federal Register
GMACT generic MACT
HAP hazardous air pollutant(s)
HC1 hydrogen chloride
HF hydrogen fluoride
HON hazardous organic NESHAP
LDAR Leak Detection and Repair
MACT maximum achievable control technology
NESHAP national emission standards for hazardous air
pollutants
NOCS Notification of Compliance Status
OAQPS Office of Air Quality Planning and Standards
OECA Office of Enforcement and Compliance Assurance
OMB Office of Management and Budget
PMACT presumptive MACT
PC polycarbonate
POD Point of Determination
ppm parts per million
ppmv parts per million by volume
ppmw parts per million by weight
SOCMI Synthetic Organic Chemical Manufacturing Industry
SSM Startup, shutdown, and malfunction
TOC total organic compounds
TRE Total Resource Effectiveness
VOC volatile organic compounds
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3.0 GENERIC MAXIMUM ACHIEVABLE CONTROL TECHNOLOGY PREAMBLE
3.1 GENERIC MACT APPROACH
Comment: Six commenters (A-97-17, IV-D-01; A-97-17, IV-
D-03; A-97-17, IV-D-04; A-97-17, IV-D-05; A-97-17, IV-D-06; A-
97-17, IV-D-07;) expressed concerns about the generic MACT
approach. There were two major concerns expressed. One
concern expressed was about the criteria proposed to determine
similarity with respect to emission controls. The other major
concern expressed was that statutory due process not be short-
circuited under the generic MACT approach.
Response: The EPA has responded to the major concerns
expressed by commenters on the generic MACT approach in the
promulgation preamble for the generic MACT rule signed on
May 15, 1999.
Comment: One commenter (A-97-17, IV-D-01) stated that
the cost and economic impacts of the proposed standards for
the AR production, AMF production, HF production, and PC
production source categories were not provided and that the
economic determination can not be short-circuited.
Response: The EPA agrees with the commenter that in
determining MACT, the economic determination Ccin iiuL be short-
circuited. The economic impacts of the proposed standards are
presented in the Basis and Purpose document for the generic
MACT rule proposal. This document can be accessed from the
docket for the proposed standards (Docket No. A-97-17, Item
No. II-B-7).
Comment: One commenter (A-97-17, IV-D-06) stated that
the EPA's proposed generic MACT approach is incompatible with
the differing "new" versus "existing" source structure
established in section 112 (a) (4) of the Act. The commenter
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(A-97-17, IV-D-06) questioned'that if the EPA establishes a
future standard based on the Generic. MACT proposal date of
October 14, 1999, is the proposal date for the new source
category the generic MACT proposal date or the applicability
proposal date? The commenter (A-97-17, IV-D-06) explained
that this is an important distinction when determining whether
new source control should apply as mandated under section
112(d)(3) of the Act.
Response: The EPA's intention was for new source MACT to
be contingent on the applicability proposal date which would
be consistent with what was intended under section 112 (a) (4)
of the Act. Separate paragraphs delineating different
applicability proposal dates will be delineated in the
applicability section of the generic MACT rule. The EPA has
clarified this intent in the applicability section of the
final rule.
Comment: Two commenters (A-97-17, IV-D-03;
A-97-17, IV-D-07) stated that the preamble suggests that the
generic MACT approach could assist States with case-by-case
MACT determinations under sections 112(j) and 112(g) of the
Act. One commenter (A-97-17, IV-D-3) requested that the EPA
clarify what the EPA believes the relationship is between the
generic MACT and the section 112(j) and section 112 (g) rules.
One commenter (A-97-17, IV-D-07) recommended that the EPA
delete the paragraph referencing case-by-case MACT
determinations.
Response: The preamble states that presumptive MACT, not
generic MACT, is intended to assist- State and local permitting
authorities in making a possible case-by-case MACT
determination. The EPA has not proposed to relate case-by-
case MACT determinations mandated under section 112 (j) and
section 112(g) of the Act with the generic MACT approach. The
EPA would, however, be able to assess what has been learned
under the presumptive MACT process to determine whether a
source category "might" be a good candidate for establishment
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of MACT under the generic MACT structure and/or approach.
Additionally, the EPA would be able to identify, and start
communication with, the stakeholders involved in the
presumptive MACT process which is an essential initial step
towards determining MACT (using the traditional or generic
MACT approach).
The EPA does not modify proposal preambles for
republication at promulgation. Therefore, the EPA has not
deleted the paragraph referencing case-by-case MACT, as
recommended by the commenter (A-97-17, IV-D-07).
Comment: One commenter (A-97-17, IV-D-06) was concerned
that, by not incorporating all applicable section 112 of the
Act requirements affecting each source category in each MACT,
may result in Title V permits numerically referencing
standards .without incorporating their content. The commenter
(A-97-17, IV-D-06) explained that the extensive cross-
referencing between the different subparts makes the
requirements difficult to understand. The commenter (A-97-17,
IV-D-06) further stated that the generic MACT regulations are
complex because the EPA is designing them to handle all
conceivable situations. The commenter (A-97-17, IV-D-06)
stipulated that the EPA would be forcing sources to face far
more frequent revisions to the MACT standards than was
intended by the Act which will raise compliance costs.
Response: The EPA agrees that cross-referencing
different regulations can often be confusing. Historically,
MACT standards have cross-referenced different regulations to
ensure that the integrity and intent of the cross-referenced
regulations are maintained. Additionally, cross-referencing
has been done to ensure that the benefits associated with
changes made to the cross-referenced provisions are
transferred to those standards that cross-reference them.
The EPA has proposed the common control requirement
subparts to reduce some of the confusion associated with
cross-referencing different regulations while maintaining the
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benefits. Confusion is reduced by the modular structure of
the common control requirement subparts whereby exceptions are
minimized and the standards are "standard." The only changes
made to the common control requirement subparts under
subsequent proposals would be those that are assessed as being
beneficial (e.g., clarifications). Historically, the EPA has
had to amend previously-promulgated rules (i.e., sometimes
numerous) to provide beneficial changes identified in
subsequent proposals incorporating similar language.
Comment: One commenter (A-97-17, IV-D-01) agreed that
the applicability component for existing and new source MACT
should be determined independent of the total number of
sources in the source category.
Response: The EPA agrees with the commenter's support
for determining the applicability component for existing and
new source MACT independent of the total number of sources in
the source category.
Comment: One commenter (A-97-17, IV-D-05) requested that
the EPA explicitly provide in the regulations for a
stakeholder process in all future generic MACT determinations.
The commenter (A-97-17, IV-D-05) explained that they were
concerned that without this requirement stipulated in
regulatory language, the application of generic MACT to small
source categories might deny them the protection of due
process.
Response: Any additional source category that uses the
generic MACT approach will rely on stakeholder involvement and
be proposed in the Federal Register for public comment.
Comment: One commenter (A-97-17, IV-G-06) stated that
the basic approach detailed in the proposed rule does not
provide adequate pollution control industry participation or
input to properly evaluate and consider application of
currently available technology to meet the statutory
requirements. The commenter explained that the preamble
stated that the EPA's first step in the proposed approach is
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to establish a stakeholder group consisting of representatives
of the affected industries, state and local agencies, and
"other interested parties." The commenter (A-97-17, IV-G-06)
stated that the control technology supply industry should also
play a major role in identifying applicable control
technologies for the source categories under review in order
to properly establish the maximum achievable control
technology for any source category.
Response: The EPA welcomes the involvement of control
equipment vendors in the process of developing rules. Indeed,
the EPA has frequently used vendor emission control data to
establish emission limits, monitoring requirements, and
maintenance schedules in their MACT standard development
process.
3.2 COMMON CONTROL REQUIREMENT SUBPARTS
Comment: One commenter (A-97-17, IV-D-03) stated that
though not addressed in their comments, they did not agree
with several of the individual technology standards set out in
the proposed 40 CFR part 63, subparts SS, TT, UU, and WW. The.
commenter (A-97-17, IV-D-03) referred the EPA to member
company comments on specific subparts.
Response: The EPA has addressed all of the commenter's
(A-97-17, IV-D-03) member company comment letters regarding
the proposed 40 CFR part 63, subparts SS, TT, UU, and WW.
Comment: One commenter (A-97-17, IV-G-05) supports the
use of the standard standard MACT approach. The commenter
(A-97-17, IV-G-05) stated that the proposed approach will
facilitate understanding of the compliance requirements, and
will eliminate conflicting or duplicative requirements.
Response: The EPA agrees with the commenter.
3.3 OTHER COMMENTS
Comment: One commenter (A-97-17, IV-G-04) stated that,
based on the proposal preamble, the reader might be led to an
incorrect evaluation of the requirements and applicability of
the rule and requested clarification on their cited items in
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the final preamble and rule. A few of the cited items
concerned process vent from batch unit operations. Another
item cited was that there were inconsistencies in the
presentation of outlet concentration standards in table 1 of
the proposal preamble. And the last item cited requested that
the EPA clarify that, for polycarbonates production, storage
vessels have an option to control to a 20 ppm HAP level.
Response: The batch unit operation provisions have been
removed from the final rule. The EPA has decided to remove
these provisions because there are currently no process vents
from solely batch unit operations regulated under the generic
MACT at this time. The EPA will add provisions, as necessary,
with future proposals. Therefore, the EPA has not made the
commenter's clarifications regarding batch unit operations in
the promulgation preamble to this rule.
The proposal preamble table 1 has not been republished in
the promulgation preamble, therefore, the HAP
concentration/TOC concentration inconsistency between the
proposal preamble and the rule has not been addressed in the
promulgation preamble. The EPA would, however, like to
clarify that the proposed rule was correct and not the
preamble.
The 20 ppm option is included for process vents, but was
included for storage vessels in'error. The 20 ppm option is
usually an option for process vents, where continuous
compliance with a 98% performance standard may be difficult
for streams with low concentrations. Since the rule requires
95% control for storage vessels, the 20 ppm option would be
less stringent only when the concentration of the vapor stream
is less than 400 ppm. It is unlikely that a vapor stream from
a storage vessel with a saturated vapor space would be below
this low level. The final rule does not include the 20 ppm
option for storage vessels.
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4.0 NATIONAL EMISSION STANDARDS FOR CLOSED VENT SYSTEMS,
CONTROL DEVICES, RECOVERY DEVICES AND ROUTING TO A FUEL GAS
SYSTEM OR A PROCESS (40 CFR Part 63, Subpart SS)
4 .1 GENERAL .
4.1.1 Cross-referencing, Grammatical, and Typographical
Comments
Comment: The EPA received many editorial comments on the
proposed regulation. These comments primarily addressed
typographical errors, minor editorial corrections, and cross-"
referencing errors.
Other types of comments included the addition of a cross-
reference to reporting requirements in the recordkeeping
provisions. Another change frequently suggested was that
instead of referring to the provisions of the referencing
subpart, the reference should be kept within subpart SS, and
changed to cross-reference the relevant section and paragraph -
of subpart SS.
Response: The EPA appreciates the effort made by
commenters to identify errors and bring them to the EPA's
attention, and many changes have been made to the rule as a
riocvii_'h of these comments. The addition of cross—ire£eirt;iiCfci;r>
serves to clarify the regulation, and gives owners and
operators subject to the rule a clearer picture of the
connection between records that must be kept and information
that must be reported to the EPA. Also, where a report is
mentioned, the cross-reference is frequently added, again for
clarification purposes. Where appropriate, the EPA revised the
rule to refer to provisions of subpart SS rather than the
referencing subpart, but this was not appropriate in all
cases, as some requirements are in fact governed by the
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referencing subpart. Comments addressing specific aspects of
the rule other than basic editorial or typographical
corrections are addressed in more detail in the section of
this BID that corresponds to the rule provisions in question.
4.1.2 Structure of the Regulation
Comment: One commenter (A-97-17, IV-D-02) provided the
EPA with extensive comments on the organization and structure
of subpart SS, with the goal of streamlining the rule and
consolidating repeated requirements. The commenter suggested
that §63.982 of the rule be deleted and its provisions
addressed in an expanded applicability section (§63.980).
According to the commenter's suggestion, this expansion of
§63.980 would consist of a paragraph that establishes
applicability of the rule on the basis of the means used to
control emissions (e.g. flare, nonflare, route to fuel gas
system or process).
The commenter (A-97-17, IV-D-02) further suggested that
many requirements from §§63.982, 63.985, 63.986, and 63.988
through 63.996 be consolidated in a single section addressing
general nonflare control and recovery device requirements,
thereby eliminating repetition of provisions, and
substantially reducing the length of the rule. This single
general nonflare control and recovery device requirements
section would also include monitoring requirements. The
commenter suggested that device-specific requirements be
placed in separate sections, thereby eliminating the
repetition of provisions common to all devices. The commenter
also recommended the consolidation of device-specific
sections, so that provisions for incinerators, boilers, and
process heaters appear in one section instead of two, and
provisions for absorbers, condensers, and carbon adsorbers
used as control devices appear in one section instead of
three. Finally, the commenter suggested that the provision
governing compliance demonstrations and notification for
replacement of an existing control or recovery device be
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placed once in §63.989, Performance testing and compliance
assessment requirements for control devices, instead of
repeating the provision in §§63.987 through 63.993 of the
rule.
Response: The EPA recognizes the importance of
streamlining and consolidating rule requirements wherever
possible, so that the owner or operator of an affected
facility may more easily determine the provisions to which he
or she is subject. To this end, the EPA appreciates the
effort made by the commenter to provide an alternative
structure to some of the provisions in the proposed rule and
to provide suggested language to implement this alternative
structure. The EPA has reviewed the commenter's suggested
changes carefully, and has decided to follow some, although
not all, of the commenter's suggestions. In the interests of
ensuring that no substantive changes resulted in the rule from
any reorganization, and that the integrity of the rule's
provisions would not be affected by any reorganization
undertaken, the EPA decided that it was not appropriate to
make all of the changes suggested by the commenter.
Furthermore, to alter the structure of the rule too
substantially would not be fair to other commenters and
interested parties, who would not have the opportunity to
provide input on the revised rule structure.
However, in cases where identical requirements were
repeated multiple times in the proposed rule, the EFA agrees
with the commenter that consolidation is possible and
desirable. The changes made by the EPA to the promulgated rule
are summarized below.
While the EPA did not delete §63.982 and revise §63.980
as suggested by the commenter, substantial changes were made
to §63.982, in order to eliminate the unnecessary repetition
of requirements. Consequently, requirements for emissions
vented through a closed vent system to a flare, nonflare
control device, routing to a fuel gas system or process, or a
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final recovery device are listed in paragraphs (b) through (e)
of §63.982, and paragraph (a) cross-references the relevant
requirements in these paragraphs for storage vessels, process
vents, low and high throughput transfer racks, or equipment
leaks. In contrast, the proposed version of the rule repeated
each set of control requirements in separate paragraphs for
each emission point, leading to considerable repetition.
The EPA also combined §§63.988 and 63.989 of the rule
into a single section governing requirements for incinerators,
boilers, and process heaters, because so many of the
requirements are the same. All of the differences in the
proposed provisions for these devices were retained verbatim
in the promulgated rule.
Similarly, the EPA consolidated §§63.990 through 63.992
into a single section governing absorbers, condensers, and
carbon adsorbers used as control devices, because of the
extensive overlap of requirements for these devices. Again,
all. the differences in the proposed provisions were retained
verbatim in the promulgated rule.
The proposed rule required the owner or operator who
elects to replace an existing control or recovery device to
notify the Administrator and perform a compliance
demonstration. This requirement appeared in §§63.987 (b) (2),
63.988(b) (3), 63.989 (b) (3), 63.990 (b) (2), 63.991 (b) (2),
63.992 (b) (2), and 63.993(b)(2) of the proposed rule. In the
promulgated rule, the EPA has deleted these paragraphs, and
placed the requirement in §63.997(c)(3). This section is
titled Performance test and flare compliance assessment
requirements, and thus is the appropriate location for a
common requirement.
Finally, §§63.988(c) (2), 63.989 (c) (2), 63.990 (c) (2),
63.991(c) (2), 63.992 (c) (2), 63.993 (c) (5), 63.994 (c) (3), and
63.995 (c) (2) of the proposed rule .contained a requirement for
the establishment of a range for monitored parameters that
indicates proper operation of the control or recovery device.
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To eliminate this repetition, in the promulgated rule, the EPA
has deleted these paragraphs, and placed the requirement in
§63.996(c) (6). Section 63.996 contains the general monitoring
provisions for subpart SS, and consequently this is the
appropriate location for this common requirement.
The final result of these changes is a substantially
consolidated, clarified subpart SS, which the EPA anticipates
will .be simpler for owners and operators to follow.
In some cases, the extensive reorganization of the rule
affected other comments and responses on the proposed rule.
These are addressed in more detail in the section of this BID
that corresponds to the rule provisions in question.
4.2 DEFINITIONS
4.2.1 Fuel gas system
Comment: One commenter (A-97-16, IV-G-01) noted that the
definition of "fuel gas system" in the proposed rule includes
the phrase "offsite and onsite piping and flow and pressure
control system." The commenter stated that the Organic Liquids
Distribution MACT may propose to regulate offsite pipelines
and equipment and that the EPA should assure that these
regulations do not overlap.
Response: The EPA acknowledges the commenter's concern
regarding overlapping, and potentially conflicting,
requirements in different regulations. It is the EPA's intent
in this case, as in all cases where owners and operators may
be affected by more Lhdu une regulation, that overlap among
requirements be addressed. In this case, any possible overlap
between subpart SS and the Organic Liquids Distribution MACT
would be addressed by that regulation when it is proposed and
promulgated.
4.2.2 Transfer Racks
Comment: A commenter (A-97-16, IV-G-01) stated that the
inclusion of the phrase "...containing a regulated material"
in the definitions of "high throughput transfer rack" and "low
throughput transfer rack" is redundant. Furthermore, the
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commenter contended, since there is no indication of a
concentration level, a concentration of 1 parts per billion
(ppb)' or less could render a rack subject to the.rule, and,
according to the commenter, this would be inappropriate. This
commenter suggested that these definitions be revised to
include the phrase "...containing a regulated material in the
concentration stated and defined in the referencing subpart."
Response: The EPA does not believe that there is any
need to make the rule changes suggested by the commenter.
Since the referencing subpart will define the circumstances
that would make a transfer rack subject to subpart SS in the
first place,-there is no need to refer back to the referencing
subpart in these definitions. If the transfer rack in question
does not meet the applicability threshold stated in the
referencing subpart, it will not be referred to subpart SS and
will not be faced with the issue described by the commenter.
For this reason, the EPA believes that the proposed
definitions of high and low throughput transfer racks are
clear, unambiguous, and do not run the danger of imposing
inappropriate requirements on transfer racks.
4.2.3 Control Device
Comment: One commenter (A-97-17, IV-D-02) stated that the
term "final recovery device" is sometimes used to indicate a
recovery device that is not a control device. If this is the
case, the commenter asserted, it should be defined as such in
§63.981 and used consistently throughout the standard.
Response: The EPA agrees with the commenter that
clarification of the use of the term "final recovery device"
was needed. For source categories where a TRE index value is
a criteria that is used to determine whether controls are
required for a process vent from a continuous unit operation,
the accurate identification of the final recovery device is
important. The TRE is determined following the final recovery
device, and for sources in these source categories, the final
recovery device is not considered to be a control device.
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Therefore, in the final rule, final recovery device has been
defined as "the last recovery device on a process vent stream
from a .continuous unit operation at an affected source in a
subcategory where the applicability criteria includes a TRE
index value. The final recovery device usually discharges to
a combustion device, recapture device, or directly to the
atmosphere."
Comment: One commenter (A-97-17, IV-D-02) asked whether
the statement in the definition of "control device" that
primary condensers on stream strippers or fuel gas systems are
not considered control devices is a clarification of their use
with batch unit operations, or a separate circumstance.
Response: First, since provisions for process vents from
batch unit operations are not included in the final rule, the ,;
definition of control device in the final rule does not
contain a sentence related to process vents from batch unit ;
operations. The sentence cited by the commenter regarding
primary condensers on steam strippers and fuel gas systems has
been retained in the final rule. The EPA intends that primary;
condensers on steam strippers not be considered control
devices in any situation. Similarly, fuel gas systems should
not be considered control devices. Since the language
regarding process vents from batch unit operations has been
removed, the confusion cited by the commenter should not
occur. In addition, a typographical error has been corrected
in the sentence citsd by the ccrrjTisnter. Stream strippers lids
been changed to steam strippers.
Comment; One commenter (A-97-17, IV-D-02) requested that
the EPA define "primary condenser" as used in the definition
of control device.
Response: The term "primary condenser" was used twice in
the definition of control device in the proposed rule. The
first instance was in relation to process vents from batch
unit operations. As discussed in the previous response, the
sentence in the control device definition that was in the
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proposed rule regarding process vents from batch unit
operations is not in the final rule. The second instance was
in the sentence that stated "Primary condensers on stream
strippers or fuel gas systems are not considered control
devices." As also noted in the previous response, this
sentence has been retained in the final rule (with a
typographical correction) . The EPA believes this use of
primary condenser in this sentence is straightforward, and
needs no additional clarification. Therefore, a definition of
primary condenser was not included in the final rule.
4.2.4 Temperature Monitoring Device
Comment: One commenter (A-97-17, IV-D-02) stated that
the definition of "temperature monitoring device" is missing a
value for the percentage tolerance.
Response: The commenter is correct. The definition of
"temperature monitoring device" has been revised to indicate
that the percentage tolerance should be ±1 percent.
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4.2.5 Add and Delete Definitions
Comment: One commenter (A-97-17, IV-D-02) stated that
definitions for "automated monitoring and recording system,"
"closed loop system," "reference method," "sampling connection
system," and "set pressure" should be deleted as these terms
do not appear in the text of the rule.
Response: The commenter is correct. "Automated
monitoring and recording system," "closed loop system,"
"reference method," "sampling connection system," and "set
pressure" were defined in the proposed rule, but never used in
the provisions. The EPA deleted these definitions from the
final rule.
Comment: One commenter (A-97-17, IV-D-08) noted that the
definition of "repaired" that applies to subpart SS is located
in subpart TT, and suggested that a definition of "repaired"
be added to subpart SS, and references to subpart SS in the
subpart TT definition be deleted.
Response: The commenter is correct, and a definition of
"repaired" has been added to the subpart SS regulation, and
references to subpart SS have been removed from the definition
of "repaired" found in subpart TT. In addition, the EPA has
added a definition of. "first attempt at repair" to subpart SS,
as this term is also used in the rule, but was not defined in
the proposed rule.
4.3 REQUIREMENTS
4.3.1 Recovery Devices
Comment: One commenter (A-97-17, IV-D-02) stated that
distinguishing among requirements in subpart SS for recapture
devices, recovery devices that are considered control devices,
and recovery devices that are not considered control devices
is confusing. Specifically, the commenter asked whether
absorbers, condensers and carbon adsorbers are always exempt
from performance tests when used as recovery devices, as
§63.993(b) (1) indicates, or only when the referencing subpart
specifies a TRE threshold as indicated by §63.993(a)(1). Or,
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the commenter inquired, does §63.993 apply only when the
recapture or recovery device is not considered a control
device according to the definition of "control device," or
only when stipulated in §63.982(b)(3)?
Response: First, the difference between a recovery
device and a recapture device should be noted. Absorbers,
carbon adsorbers, and condensers may be either recapture
devices or recovery devices. The determining factor whether
an adsorber, carbon adsorber, or condenser is a recovery
device or a recapture device is the fate of the recovered
chemicals. If the recovered chemicals are used, reused, or
sold, then the device is considered to be a recovery device.
If the recovered chemicals are normally not used, reused, or
sold, then the device is considered to be a recapture device.
The example in the final definition of recapture device is
when chemicals are recovered primarily for disposal.
Recapture devices are always considered to be control devices.
The EPA understands that there could be confusion
regarding when a recovery device is a control device and when
it is not. With two exceptions, a recovery device is
considered to be a control device. The first exception is for
process vents from continuous unit operations at an affected
source in a source category where the applicability criteria
includes a TRE index value. Therefore, in the final rule,
recovery devices used on back end process vents from
continuous unit operations at acetal resins production
facilities, and recovery devices on process vents from
continuous unit operations at polycarbonates production
facilities, are not considered control devices. The second
exception is a primary condenser on a steam stripper.
Since a recovery device used in any situation other than
those cited above is considered to be a control device, the
device is subject to the provisions of §63.990 in the final
rule. The performance testing requirements are no different
for these recovery devices than for an incinerator or other
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combustion device. For control devices for process vents, a
performance test is always required. For storage vessels and
low throughput transfer racks, a performance test or a design
evaluation is required. A performance test is not required
for control devices used only to control emissions from
equipment leaks.
Therefore, to answer the specific question asked by the
commenter, a performance test is required for recovery devices
(except primary condensers on steam strippers) used on process
vents from continuous unit operations at affected sources in
source categories where the applicability criteria do not
include a TRE index value. That is, performance tests are
required for front end process vents from continuous unit
operations at acetal resin production facilities, process
vents from continuous unit operations at acrylic and
modacrylic fiber production facilities, and process vents from
continuous unit operations at hydrogen fluoride production
facilities.
As noted earlier, recovery devices on back end process
vents from continuous unit operations at acetal resins
production facilities, and recovery devices on process vents
from continuous unit operations at polycarbonates production
facilities, are not considered to be control devices. In
these instances, the TRE index value is determined after the
final recovery device, which is defined in the final rule as
the last rer.nvery device on a process vent stream from a
continuous unit operation prior to discharge to a control
device or to the atmosphere. If the TRE index value after the
last recovery device is below the cutoff value in the table
for the source category in §63.1103, then a control device is
needed to reduce emissions in accordance with the applicable
control requirements. If the TRE is greater than the
applicable cutoff, then the final recovery device is subject
to the requirements of §63.993, which addresses final recovery
devices used to maintain a TRE above a specified level.
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Several changes have been made in the final rule to
clarify this potentially confusion situation. The EPA
believes that these changes answer the final question posed by
the commenter. First, in the final rule, control device has
been defined as follows:
Control device means, with the exceptions noted below, a
combustion device, recovery device, recapture device, or any
combination of these devices used to comply with this subpart
or a referencing subpart. For process vents from continuous
unit operations at affected sources in source categories where
the applicability criteria includes a TRE index value,
recovery devices are not considered to be control devices.
Primary condensers on steam strippers or fuel gas systems are
not considered to be control devices.
Second, §63.982(e), which is equivalent to what was
§63.982 (b) (3) in the proposed rule, has been reworded as
follows: "Owners or operators who use a final recovery device
to maintain a TRE above a level specified in a referencing
Subpart ^wn L±. k-' 1 a±.i, t;uU_so-Lwlio L j_ win |->J.UL^e£>£>veil Lo L L uiu
cunlinuuub—unit opididliuris shall meet the requirements in
§63.9.93 ..."
Comment: One commenter (A-97-17, IV-D-02) inquired why
recovery devices (primary condensers) used on process vents
from batch unit operations are not included in paragraph
(b)(3) of §63.982 and what requirements apply to them.
Response: The process vent batch unit operation
requirements have been removed from the final rule because
none of the facilities subject to requirements under the
generic MACT currently have process vents from batch unit
operations. Requirements for process vents from batch unit
operations may be added under the generic MACT in future
proposals, as necessary. Since subpart SS no longer includes
requirements for batch unit operations, this commenter's
concern is no longer relevant.
4.3.2 Transfer Racks
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Comment: Two commenters (A-97-17, IV-D-02; A-97-16, IV-
G-01) noted that §63.982 (c) (2), which addresses provisions for
low throughput transfer racks, states, "The requirements of
§63.984 through§63.986 do not apply to high throughput
transfer racks..." One commenter ( A-97-16, IV-G-01) stated
that either "high" should be changed to "low," or the sentence
should be deleted from this paragraph. The other commenter
(A-97-17, IV-D-02) said that the sentence should be deleted.
Response: The sentence in question applies only to high-
throughput transfer racks, and appeared correctly in proposed
§63.982 (c) (3). This sentence has been deleted from
§63.982 (c) (2) in the final rule. As noted earlier, this
section of the rule has been substantially reorganized since
proposal.
4.4 CLOSED VENT SYSTEMS
4.4.1 Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that
the phrase "Except for closed vent systems operated and
maintained under negative pressure..." should be moved from
§63.983 (b) (1) to §63.983 (a), which would be consistent with
§63.120(d)(7) and (e)(6) of the HON.
Response: The commenter is correct. The exemption for
systems operated and maintained under negative pressure
applies to the requirements of §63.983 (a), consistent with the
HON, and the phrase "Except for closed vent systems operated
cind maintQj-nGd under nsgativs pressure. . ." has been muveu from
§63.983(b) to §63.983(a) in the final rule.
Comment: The commenter (A-97-17, IV-D-02) stated that, as
proposed, there is ambiguity in §63.983 (b) regarding whether a
given piping component in a closed vent system is subject to
closed vent requirements or equipment leak provisions. The
commenter suggested that this be rectified by stipulating that
closed vent system provisions apply only to systems
constructed of ductwork, consistent with §63.119(f)(2) of the
HON. The commenter provided suggested revisions to this
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paragraph, exempting closed vent systems constructed of hard-
piping from paragraphs (c) and (d) of §63.983 (Closed vent
system inspection procedures and Closed vent system leak
repair provisions).
Response: The reason for the commenter's confusion and
claim that the provisions of §63.983(b) are ambiguous is not
clear. The paragraph in question explicitly states that
owners or operators of closed vent systems constructed of
hard-piping are required to conduct an initial inspection
according to the provisions of §63.983 (c) and annual visual
inspections for visible, audible, or olfactory indications of
leaks, while owners or operators of closed vent systems
constructed of ductwork are required to conduct an initial and
annual inspections according to the provisions of §63.983(c).
Furthermore, there is no indication in this section that any
closed vent systems are exempt from the leak repair
requirements of paragraph (d), and there is no ambiguity about
this.
The paragraph in the HON referred to by the commenter
governs the routing of storage vessel emissions to a fuel gas
system or process, and §63.119(f)(2) states: "If the
emissions are conveyed by a system other than hard-piping, any
conveyance system operated under positive pressure shall be
subject to the requirements of §63.148 of this subpart."
Section 63.148 contains leak inspection provisions, and thus
the implication of §63.119(f)(2) is that a conveyance system
constructed of hard-piping would not be subject to these
provisions. To apply the language from this specific case in
the HON more broadly to the general closed vent system
requirements of subpart SS is not appropriate.
4.4.2 Inspection Procedures
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.983{c)(1)(ii) should be revised to say "...the detection
instrument shall meet the performance criteria of Method 21 of
40 CFR part 60, appendix A, except the instrument response
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factor criteria in section 3.1.2 (a) of Method 21 may be for
the representative composition of the process fluid and not of
each individual VOC in the stream. For process streams that
contain nitrogen, air, or other inerts that are not organic
HAP or VOC, the representative stream response factor may be
determined on an inert-free basis."
Response: The exceptions to Method 21 described in
§63.983 (c) (1) (ii) are inspection specifications, and they are
not optional, and therefore the commenter's suggested use of
the word "may" instead of "shall" is not appropriate. The
paragraph has been revised in the final rule to state that
"...the detection instrument shall meet the performance
criteria of Method 21...except the instrument response factor
criteria ... must be for the representative composition of the
process fluid and not of each individual VOC in the stream.
For process streams that contain nitrogen, air, or other
inerts that are not organic HAP or VOC, the representative
stream response factor must be determined on an inert-free
basis."
4.4.3 Leak Repair
Comment: One commenter (A-97-17, IV-D-02) suggested that
language specifying that "technically infeasible repairs"
include, but are not limited to, procedures involving imminent
or potential risk of accident or damage be added to
§63.983(d)(3), which establishes delay of repair requirements.
Response: The EPA agrees with the cuimnenter that delay
of repair is also allowed in situations where repair is
unsafe. The EPA has revised §63.983(d)(3) to specify that
delay of repair is allowed if repair is "technically
infeasible or unsafe." It is not necessary to include
specific details or explanations of unsafe as suggested by the
commenter, as the recordkeeping requirement in
§63.998(d) (1) (iii) (E) requires the owner or operator to
explain why the repair was delayed.
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Comment: One commenter (A-97-17, IV-D-02) stated that
the reference in §63.983(d)(3) to "closed vent system
shutdown, as defined in the referencing subpart" should be
changed to state "...,as defined in §63.981."
Response: The EPA agrees with the commenter, and has
revised the rule accordingly. Since "closed vent system
shutdown" is defined in §63.981 of subpart SS for the purpose
of provisions in subpart SS, this is the definition that
should be referenced in §63.983(d)(3).
4.5 NONFLARE CONTROL DEVICES USED TO CONTROL EMISSIONS FROM
STORAGE VESSELS AND LOW THROUGHPUT TRANSFER RACKS
4.5.1 Requirements
Comment: One commenter (A-97-17, IV-D-02) suggested
amending paragraph '(a) of §63.985 to include planned routine
maintenance as an exempted activity from the requirements to
operate and maintain the nonflare control device so that the
monitored parameters remain within the ranges specified in the
Notification of Compliance Status report.
Response: The provisions of subpart WW for storage
vessels referenced by the generic MACT rule allow for shutdown
of control devices during periods of planned routine
maintenance for control devices used on storage vessels.
Storage vessels are unusual because emissions occur as long as
they contain liquids. There is no reason to expect the
storage vessels to be empty during periods when other process
equipment is shutdown for maintenance. However, the EPA
disagrees with the commenter's suggestion that the owner or
operator should be exempt from the requirement to operate the
control device during planned routine maintenance for other
emission sources. The expectation is that control devices
will be operated within specified parameters except during
periods of startup, shutdown, and malfunction. Because
planned, routine maintenance is an integral part of normal
operation, it is not appropriate to exempt these periods from
the requirement to comply with control device specifications.
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If a control system does not meet the applicable
specifications during planned routine maintenance, this shall
be recorded and reported in the source's Periodic Report.
4.5.2 Performance Testing and Design Evaluation
Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.985 (b) (1) is self-contradictory as written and meaning is
unclear.
Response: The paragraph means that the owner or operator
shall submit a design evaluation or performance test results,
but the EPA agrees with the commenter that the proposed
language was confusing and difficult to follow. The EPA has
revised §63.985 (b) by adding paragraph (b) (3), stating: "If a
design evaluation or performance test is required in the
referencing subpart, or was previously conducted and submitted
for a storage vessel or low-throughput transfer rack, then a
performance test or design evaluation is not required." In
addition, the EPA has revised §63.983 (b) to state: "...except
as provided in paragraphs (b) (2) and (b) (3) of this section."
These changes clarify the requirements as they were presented
in the proposed rule.
Comment: One commenter (A-97-17, IV-D-02) observed that
there are no design evaluation requirements given for
absorbers in §63.985 (b) (1) (i), while there are for all other
control devices. This commenter wondered whether there should
be such dRsirjn evaluation criteria.
Response: The commenter is correct that there are no
design evaluation requirements given for absorbers in
§63.985(b)(1)(i). Owners or operators are allowed to use an
absorber to comply with the specified requirements for storage
vessels and low throughput transfer racks. Further, owners or
operators are allowed to use a design evaluation to
demonstrate that the absorber achieves the required control
efficiency. Since there is not a specific paragraph
addressing the design evaluation for absorbers, the owner or
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operator would need to meet the general information specified
in to §63.985(b)(1)(i), which is "documentation demonstrating
that the control device being used achieves the required
control efficiency during the reasonably expected maximum
storage vessel filling or transfer loading rate," along with a
description of the gas stream being routed to the absorber.
Comment: One commenter (A-97-17, IV-D-02) asserted that
the following sentence in §63.985 (b) (1) (i) is almost
incomprehensible as written and suggested adding parentheses
around the additional requirement for storage vessels as
follows: "...This documentation is to include a description of
the gas stream that enters the control device, including flow
and regulated material content, (and additionally for storage
vessels, under varying liquid level conditions,) and the
information specified in paragraphs (b)(1)(i)(A) through
(b)(1)(i)(E) of this section, as applicable. This
documentation shall be submitted with the Notification of
Compliance Status report as specified in §63.999(b)(2)."
Response: The commenter is correct regarding this
sentence. In order to clarify the provisions of
§63.985 (b) (1) (i), the EPA has revised the paragraph to read as
shown below:
"...This documentation is to include a description of the
gas stream that enters the control device, including flow
and regulated material content, and the information
specified in paragraphs (b)(1)(i)(A) through (b)(1)(i)(E)
of this section, as applicable. For storage vessels, the
description of the gas stream that enters the control
device shall be provided for varying liquid level
conditions. This documentation shall be submitted with
the Notification of Compliance Status as specified in
§63.999(b) (2) ."
Comment: One commenter (A-97-17, IV-D-02) suggested that
§63.985(b) (1) (ii) be amended in order to consolidate
requirements that overlap with paragraph (b) (1) (iii) . The
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commenter states that §63.985(b)(1)(iii) should then be
deleted. The commenter's revision is as follows: "A
performance test is acceptable, whether conducted for this
purpose or to demonstrate compliance for a process vent or
high-throughput transfer rack or for any other purpose, to
demonstrate compliance with emission reduction requirements
for storage vessels and transfer racks."
Response: The EPA agrees with the commenter's suggestion
that the provisions of §63.985(b) (1) (ii) and (b) (1) (iii) be
consolidated in a single paragraph, thereby clarifying these
requirements and eliminating some redundancy in the rule. The
EPA has deleted §63.985 (b) (1) (iii) and revised
§63.985 (b) (1) (ii) as follows: "A performance test, whether
conducted to meet the requirements of this section, or to
demonstrate compliance for a process vent or high-throughput
transfer rack as required by §§63.988(b), 63.990 (b), or
63.995 (b), is acceptable to demonstrate compliance with
emission reduction requirements for storage vessels and
transfer racks."
4.5.3 Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) suggested that
§63.985 (c) (2) be revised to include a reference to the
operating permit application or amendment, as follows:
"...specified in the Notification of Compliance Status report
or in the operating permit application or amendment."
Response: The ccmmcnter's suggestion does nuL
substantively change the intent of §63.985 (c) (2), and the EPA
has made the suggested change in the final rule.
4.6 FLARE REQUIREMENTS
4.6.1 Requirements
Comment: One commenter (A-97-16, IV-G-01) asserted that
the EPA should refer to 40 CFR 63.11(b) for flare requirements
instead of creating an additional flare section in this rule.
The commenter stated that this would eliminate redundancy and
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facilitate the modification of flare requirements when
necessary.
Response: The commenter is correct regarding the
benefits of having flare requirements located in a single
location, so that redundancy is eliminated and necessary
modifications may be more easily made. The EPA agrees that it
is appropriate in this case to refer to 40 CFR 63.11(b) for
flare requirements. However, the provisions of 40 CFR 63.11(b)
do not address all of the requirements covered by §63.987, and
thus §63.987 has not been replaced in its entirety by this
reference. Instead, §63.987 (a) has been revised to refer to
40 CFR 63.11(b), and all the requirements proposed in this
paragraph have been deleted. Section 63.987(b) and (c),
however, have been retained intact as proposed, because they
establish compliance demonstration and monitoring requirements
not addressed by 40 CFR 63.11(b).
Comment: One commenter (A-97-17, IV-D-02) suggested
substantial changes to §63.987(a) (6) which would combine the
provisions of §63.987 (a) (6) (i) and (ii) into a single
paragraph, arguing that the intent of the paragraph would be
maintained, and the provisions would be abbreviated.
Response: Since the EPA has revised the rule to refer to
the provisions of 40 CFR 63.11(b) in §63.987(a), eliminating
all other provisions first proposed in this paragraph, the
commenter's suggestions are no longer relevant.
4.6.2 Compliance Assessment
Comment: One commenter (A-97-17, IV-D-02) recommended
that, the EPA add a definition for "n" in Equation 3 of
§63.987 (b) (3) (ii) . The commenter recommended adding the
definition as follows: "n = number of sample components."
Response: The EPA agrees that the addition of this
definition is appropriate in order to completely define all
relevant terms in the equation, and the EPA has made the
change suggested by the commenter.
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Comment: One commenter (A-97-17, IV-D-02) noted that the
current version of ASTM D1946-77 referred to in
§63.987 (b) (3) (ii) is ASTM D1946-90. The commenter also noted
that ASTM D2382-76 was discontinued in 1994 by ASTM.
Response: The EPA has revised the final rule to include
the correct version of ASTM D1946-90, and has also removed the
reference to discontinued ASTM D2382-76.
Comment: One commenter (A-97-17, IV-D-02) stated that the
cross-reference to the compliance assessment report in
§§63.987(b) (2), 63.989(b) (3), 63.990(b) (2) (ii),
63.991 (b) (2) (ii), 63.992 (b) (2) (ii) should be changed from
63.999 (a) (2) (ii) to 63.999 (a) (1) (ii) . The sentence as proposed
reads. "The compliance assessment report shall be submitted
... within 60 days...as provided in §63.999(a) (2) (ii) ."
Response: The commenter is correct. The cross-reference
as proposed referred to the requirements for the content of
the report, whereas the revisions suggested by the commenter
refers to general requirements for the report, including
timing of submission. The EPA has revised this cross-
reference accordingly.
4.6.3 Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that a
reference to reporting requirements should be included in
§63.987 (c), so that the sentence reads as follows: "Flare
monitoring and compliance records shall be kept as specified
in §63.998(a)(I) and reported as specified in §63.999(b)(9)."
Response: The EPA agrees that this is a useful change to
make, as it clarifies the relationship between recordkeeping
and reporting requirements, and should simplify the owner or
operator's task of determining his or her reporting
responsibilities. The EPA revised the rule as suggested by the
commenter, except that the cross-reference changes were
amended to reflect other changes made in the rule.
4.7 INCINERATORS, BOILERS, AND PROCESS HEATERS
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Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §§63.988(c)(1) and 63.989(c)(l) to the
requirement to record monitoring results, "as specified in
§63.998(b)" should be modified to also cross-reference
§63.998 (c) (3) and (4) .
Response: While the commenter is correct that
recordkeeping requirements for monitoring results are also
specified in §63.998(c)(3) and (4), there are also monitoring
recordkeeping requirements specified in §63.999(c)(1) and (2).
Consequently, the EPA has revised this cross reference to
refer more broadly to "§63.998(b) and (c), as applicable."
4.8 ABSORBERS, CONDENSERS, AND CARBON ADSORBERS USED AS
CONTROL DEVICES
4.8.1 Requirements
Comment: A commenter (A-97-17, IV-D-02) stated that
§63.990 (b) (1) refers to any absorber used as a recapture
device and §63.990(b)(2)(ii) refers to any absorber used as a
control device, and asked whether these should be the same,
and which - recapture device or control device - is intended.
The commenter noted a similar discrepancy in §§63.991 and
63.992.
Response: The EPA agrees that the terminology in these
paragraphs should be consistent. The proper language should
be when an absorber/condenser is used as a control device.
The proposed §§63.990, 63.991, and 63.992, which addressed
absorbers, condensers, and carbon adsorbers, used as control
devices have been combined into one section - §63.990 - in the
final rule. This was because the requirements for these
recovery devices used as control devices were largely
redundant. The language in the final §63.990 clearly and
consistently refers to the situation when an absorber,
condenser, or carbon adsorber is used as a control device.
Comment: One commenter (A-97-17, IV-D-02) stated that the
meaning of the phrase "the applicable applicability
determination provisions of a referencing subpart" with which
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the owner or operator shall comply when replacing a recovery
device, or replacing a control device with a recovery device,
which is found in §§63.990 (b) (2) (i), 63.991 (b) (2) (i),
63.992 (b) (2) (i), and 63.993 (b) (2), is unclear. The commenter
suggested that it would be clearer if the required
determination were specified, for example indicating whether a
TRE index value determination must be performed.
Response: The EPA agrees with the commenter's statement
that the proposed rule language is confusing. Accordingly,
the rule has been revised to require that the owner or
operator comply with the "applicable provisions of a
referencing subpart or this subpart." Furthermore, the rule
has been consolidated so that this requirement appears only
once in the final rule, in §63.997 (c) (3).
4.8.2 Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §§63.990 (c) (1), 63.991 (c) (1), and 63.992(c)(l) to
the requirement to record monitoring results, "as specified in
§63.998 (b)" should be modified to also cross-reference
§63.998 (c) (3) and (4) .
Response: While the commenter is correct that
recordkeeping requirements for monitoring results are also
specified in §63.998 (c) (3) and (4), there are also monitoring
recordkeeping requirements specified in §63.999(c)(1) and (2).
Consequently, the EPA has revised this cross reference to
refer more broadly to "§53.938 (b) and (c), as applicable."
4.9 ABSORBERS, CONDENSERS, AND CARBON ADSORBERS AND OTHER
RECOVERY DEVICES USED AS FINAL RECOVERY DEVICES
4.9.1 Performance Test Requirements
Comment: Two commenters (A-97-17, IV-D-08; A-97-17, IV-D-
08) noted that §63.993 (b) (2) requires that, if an owner or
operator replaces an existing final recovery or control device
with a recovery device, the owner or operator must notify the
EPA and comply with applicability provisions. The commenters
requested that §63.993 (b) (2) be modified to clarify that an
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owner or operator be allowed to replace a recovery device that
is similar in all material respects (e.g., devices that are
manufactured by the same manufacturer and are the same model)
without needing to notify the EPA, even if it is not permitted
by the applicable title V permit. One commenter proposed
language for this paragraph that specifies that the
notification requirement is for replacement of a control
device with a recovery device or replacement of an existing
final recovery device with a different recovery device. The
commenter suggested that the EPA explain in the final preamble
that "different" means "not the same in all material
respects." One other commenter suggested that an example of
recovery devices that are similar in all respects would be
devices manufactured by the same manufacturer with the same
model number. One commenter also noted that the cross-
reference to §63.999(d) is incorrect and should be changed to
§63.999 (b) (7) .
Response: Due to revisions in the final rule, the
paragraphs referred to by the commenters are §63.993 (c) (3) and
§63.999(c)(7). The EPA doubts that a control or final
recovery device will ever be replaced with another that is
exactly the same in all material respects, even devices from
the same manufacturer with the same model number. Further,
the EPA believes that it would be difficult to define specific
criteria for each type of device that would be applied to
determine that two devices are materially the same. The EPA
also believes that a demonstration by an owner or operator
that two devices were the same in all material respects would
likely be as time consuming as a new compliance demonstration.
Therefore, the EPA did not make the rule change requested by
the commenter or provide the suggested preamble discussion.
The cross referencing error was corrected.
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.993(c)(5) should be revised to specify that the monitoring
range should be based upon a prior TRE index value
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determination- rather than a prior performance test. The
commenter suggested the following language: "The range may be
based upon a prior TRE index value determination meeting the
specifications in §63.997 (b) (1) or upon existing ranges or
limits established under a referencing subpart."
Response: Under the reorganized subpart SS, this
paragraph appears in §63.996 (c) (6) instead of being repeated
in various sections of the rule. That revised, consolidated
paragraph refers to establishing the range for a control or
recovery device, so the issue raised by the commenter
regarding how to refer to prior performance test or TRE index
value determination results is pertinent. In order to address
this issue, the EPA revised the rule to include the following
sentence in §63.996 (c) (6) : "The range may be based upon a
prior performance test meeting the specifications of
§63.997(b)(1) or a prior TRE index value determination, as
applicable, or upon existing ranges or limits established.
under a referencing subpart."
4.9.2 Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §63.993 (c) (3) to the requirement to record
monitoring results, "as specified in §63.998 (b)" should be
modified to also cross-reference §§63.998(c)(3) and (c)(4).
The commenter further suggested that §63.993 (c) (1) and (c) (2)
be modified by the addition of the sentence, "Monitoring
results shall be recorded as specified in §§63.938(b), (c) (3),
and (c) (4)," as the second to last sentence of the paragraph.
Response: While the commenter is correct that
recordkeeping requirements for monitoring results are also
specified in §63.998 (c) (3) and (4), there are also monitoring
recordkeeping requirements specified in §63.999(c)(1) and (2).
Consequently, the EPA has revised this cross reference to
refer more broadly to "§63.998(b) and (c), as applicable." The
commenter's suggestion that the monitoring cross-reference
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sentence be added to §63.993(c)(1) and (2) is also
appropriate, and the EPA revised the rule accordingly.
4.10 HALOGEN SCRUBBERS AND OTHER HALOGEN REDUCTION DEVICES
4.10.1 General
Comment: This commenter (A-97-16, IV-G-01) stated that
since paragraph (b)(2) of §63.994 uses the phrase "combustor,"
the EPA must either define this term or replace it with
another defined term.
Response: The EPA has revised this paragraph to use the
term "combustion device" instead of"combustor."
4.10.2 Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §63.994(c)(1) to the requirement to record
monitoring results, "as specified in §63.998 (b)" should be
modified to also cross-reference §63.998(c) (3) and (c) (4) .
Response: While the commenter is correct that
recordkeeping requirements for monitoring results are also
specified in §63.998(c)(3) and (4), there are also monitoring
recordkeeping requirements specified in §63.999(c)(I) and (2).
Consequently, the EPA has revised this cross reference to
refer more broadly to "§63.998 (b) and (c), as applicable."
4.11 GENERAL MONITORING REQUIREMENTS FOR CONTROL AND RECOVERY
DEVICES
4.11.1 Alternative Monitoring Requirements
Comment: One commenter (A-97-17, IV-D-02) asked that
§63.996 (b) (1) (ii) be revised to replace the reference to the
referencing subpart with a cross-reference to §63.998 (c) (4),
in the following manner: "The Administrator approves the use
of alternatives to any monitoring requirements or procedures
as provided in the §63.998(c)(4)."
Response: The commenter is partially correct. The
suggestion to include a cross-reference to alternative
monitoring requirements is appropriate. However, there could
also be relevant provisions in the referencing subpart, and so
it is not appropriate to eliminate the reference to the
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referencing subpart. Furthermore, the EPA has revised the rule
to move the provisions governing alternative monitoring
requirements to §63.996(d) and the paragraph cited by the
commenter now includes a reference to both §63.996(d) and the
referencing subpart.
4.11.2 Backup Monitoring Equipment
Comment: One commenter (A-97-16, IV-G-01) stated that
paragraph (b) (2) of §63.996, which governs the use of backup
monitoring equipment and reporting results during a given time
period, could be interpreted to mean that all the data from
all the instruments used during the relevant six month period
must be reported. The commenter proposed that the sentence be
revised to read "...for the time during the six month period
that the instrument was relied upon to demonstrate
compliance," to clarify that results from each monitoring
instrument must be reported only for the periods during which .
they are relied upon to demonstrate compliance.
Response: The commenter's suggestion is consistent with
the EPA's intent, and the EPA has revised the rule
accordingly.
4.11.3 Operation and Maintenance of CPMS
Comment: One commenter (A-97-17, IV-D-02) asserted that
the provisions of §63.996(c)(1) are repeated in more detail in
§63.996 (c) (3) and thus this paragraph should be deleted.
Response: While the commenter is correct that some of
the provisions in these tv.'C paragraphs overlap and could be
consolidated, there are distinctions between these paragraphs
as well. In the interests of maintaining these distinctions
and ensuring that none of the intent of the rule is lost or
altered, the EPA chose to leave the rule as proposed.
Comment: One commenter (A-97-17, IV-D-02) stated that
the requirement in §63.996 (c) (2) (ii) for an owner or operator
to report actions taken in accordance with the startup,
shutdown, and malfunction plan in the startup, shutdown, and
malfunction report is incorrect. The commenter asserts that
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the paragraph should be revised to require that such, actions
be recorded as specified in §63.998(c) (1) (ii) (E) .
Response: The commenter is correct that under
subpart SS, when the startup, shutdown, and malfunction plan
is followed and the continuous parameter monitoring system
(CPMS) is repaired immediately, the owner or operator is
required only to keep a record of these actions. Subpart SS
does not require owners or operators to submit semiannual
startup, shutdown, and malfunction reports, although the
referencing subpart may include such a requirement, or may
refer the owner or operator to the general provisions (subpart
A of part 63), which include such a requirement. Thus, the
change requested by the commenter is appropriate, and the EPA
has revised this paragraph of the rule to cross-reference the
appropriate recordkeeping requirement in §63.998 (c) (I) (ii) (E) .
Comment: One commenter (A-97-17, IV-D-02) stated that
the EPA should specify in §63.996(c)(2)(iii) that the
operation and maintenance records that the EPA may use to
determine whether acceptable operation and maintenance
procedures for CPMS are being followed are those records
specified in §63.998 (c) (1) (i) and (c) (1) (ii) .
Response: The commenter's requested revisions constitutes
a clarification of what is intended by operation and
maintenance records, and it is thus a useful change. The EPA
agrees with the commenter that these are the relevant records,
and has revised the rule to cross-reference the recordkeeping
requirements of §63.998(c)(1)(i) and (ii). The EPA also notes
that §63.996(c) (2) (iii) says that the Administrator's
determination of whether acceptable practices are being used
will be based on information that "may include, but is not
limited to" the listed items, including operation and
maintenance records.
4.12 PERFORMANCE TEST AND COMPLIANCE ASSESSMENT REQUIREMENT
FOR CONTROL DEVICES
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Comment: One commenter (A-97-17, IV-D-02) noted that
§63.997 (e) (1) (ii) contains an incorrect cross-reference to
§63.997 (e) (1) (i) which should be revised to
§63.997(e)(1)(ii)(D). Further, the commenter stated that the
reference to "combustion, recovery, control or recovery
device" should be revised to read "control or recovery
device."
Response: The cross-reference change suggested by the
commenter is correct, and the revision has been made in the
final rule. The commenter's observation that the phrase
"combustion, recovery, control or recovery device" is wrong is
also correct. To be consistent with §63.997 (e) (1), the EPA has
revised this phrase to state "control or halogen reduction
device."
4.13 RECORDKEEPING REQUIREMENTS
4.13.1 Performance Test Records
Comment: One commenter (A-97-17, IV-D-02) states that
the cross-reference in §63.998 (a) (2) (ii) (A) to the Initial
Compliance Status report should be changed from §63.999 (a) (1)
to (a) (2) .
Response: Because of changes made to consolidate the
reporting requirements of subpart SS, the commenter's
suggested correction is no longer appropriate, although the
EPA agrees that the cross-reference as proposed was incorrect.
The correct cross-reference is to §63.999 (b). In addition,
the EPA revised the name cf this report to NotificaLiun of
Compliance Status, in order to be consistent with other MACT
standards.
Comment: One commenter (A-97-17, IV-D-02) stated that the
record retention period should be clearly stated in §63.998,
and that it should be consistent for all records that must be
retained, except for records related to a piece of equipment
that should be kept for the life of the equipment. As
proposed, the commenter said, the rule requirements are
confusing, as paragraph (b)(5)(i)(F)(4) requires the
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description of the monitoring system to be kept as long as it
is current, but no less than 5 years 'from the date of
creation; paragraph (b)(5)(ii)(c) requires records to be kept
as long as required by the referencing subpart; and paragraph
(d)(4) requires equipment records to be kept for the life of
the equipment and operational records to be kept for 2 years.
Response: While the commenter's interest in clarity and
consistency of recordkeeping requirements is reasonable, the
EPA does not agree that the record retention period must be
the same for all records. However, the 2 year record
retention period in §63.998(d)(1) and (4) has been changed to
5 years in order to be consistent with the EPA's 5 year
recordkeeping requirement for MACT standards. The rationale
for the lifetime (of the equipment) record retention
requirements is that this information is relevant as long as
the equipment is in use. Finally, some record retention
periods are left to the discretion of the referencing subpart
as there may be circumstances particular to that subpart that
are used to establish the record retention requirement.
4.13.2 Continuous Monitoring Records
Comment: One commenter (A-97-17, IV-D-02) recommends
that paragraphs (a)(3) and (b)(3) of §63.998 of the rule be
amended to cross-reference the associated reporting
requirements §§63.999 (a) (2) (iii) (C) and (b) (6), respectively.
Response: Section 63.998 (a) (3) establishes recordkeeping
requirements for owners or operators using a recovery device
to maintain a TRE above a specific level. Paragraph (b)(3)
establishes monitoring recordkeeping requirements, applicable
except when an alternative monitoring or recordkeeping system
has been approved. The commenter's suggested revisions cross-
reference, respectively, the performance test report
requirements, and the periodic reporting requirements. These
additions to the rule, while not necessary, may clarify the
owner or operator's reporting requirements, and thus are
appropriate revisions to make. The EPA has revised the
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promulgated rule accordingly, while noting that the cross-
reference to the periodic reports has been revised to
§63.999(c).
Comment: One commenter (A-97-17, IV-D-02) recommends
including the specific cross-reference for the Initial
Compliance Status Report (now the Notification of Compliance
Status report in the final rule) and the Periodic Report
referred to in §63.998 (b) (5) (i), (b) (5) (ii) (A), and
(b) (5) (ii) (B) .
Response: The EPA agrees with the commenter that this
change adds clarity to the requirements of the rule. The EPA
has revised and simplified the reporting requirements in the
promulgated rule, and the added reference to the Notification
of Compliance Status Report "as specified in §63.999 (b)" and :
to the Periodic Report "as specified in §63.999 (c)" reflects
those changes.
Comment: One commenter (A-97-17, IV-D-01) stated that
§63.998 (b) (5) (ii) (D) (I) should be modified to specify that the
3-hour average value won't be considered an excursion if the
owner or operator follows the startup, shutdown, and
malfunction plan and "maintains the records specified in
paragraph (d)(3) of this section."
Response: The EPA agrees that the commenter's suggested
change would clarify the EPA's intent. The EPA has changed
the final rule to allow an owner or operator to keep records
and determine excursions on a daily basis Ldlher than on the
proposed 3-hour basis. The EPA has also made changes to this
section of the rule to clarify that the provisions governing
excursions apply throughout the section, not just under the
alternative recordkeeping scenario described in §63.998(b)(5),
and thus the cross-reference that has been added is to
§63.998(b) (6) (i) (A) .
Comment: Two commenters (A-97-17, IV-D-02; A-97-16, IV-G-
01) pointed out that §63.998(b)(1) discusses continuous
records and monitoring data handling, and references
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subparagraphs (b) (1) (i) and (b) (1) (ii) . However, this
paragraph also contains subparagraphs (iii) and (iv). One
commenter (A-97-16, IV-G-01) asserted that paragraph (b)(1) or
(b)(1)(i) should indicate that (ii) and (iii) are options. The
other commenter (A-97-17, IV-D-02) stated that the reference
should be to "(b)(1)(i) or (b)(l)(ii) or (b)(l)(iv)."
Response: While the EPA agrees with the commenter's
contention that this paragraph as proposed was confusing, the
commenters' suggestions do not fully address subparagraphs
(iii) and (iv). In order to clarify the requirements of this
paragraph, the EPA has revised §63.998 (b) (1) to state that the
owner or operator "...shall maintain a record as specified in
paragraphs (b) (1) (i) through (iv) of this section, as
applicable."
Comment: One commenter (A-97-17, IV-D-02) stated that
the 2 hours allotted for retrieving data regarding the
monitoring system description in §63.998(b)(5)(i)(F)(4) is not
a realistic time allowance. The commenter asserted that the
standard should require all applicable records to be
accessible within 24 hours.
Response: The EPA disagrees with the commenter and has
retained the requirement for monitoring data to be retrieved
within- 2 hours as proposed. The monitoring system description
is a fundamental piece of information that the EPA may choose
to review for the purposes of assessing compliance, and it is
important, therefore, that this information be readily
available to the EPA when conducting an inspection.
4.13.3 Control and Recovery Device Monitoring Records
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.998(c)(3)(i) and (iii) should include a reference to the
recovery device monitoring provisions of §63.993 (c) in the
list of references to equipment monitoring parameters to be
monitored for different control and recovery devices.
Response: The EPA agrees with the commenter and has made
the suggested change in the final rule.
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Comment: A commenter (A-97-17, IV-D-02) claimed that
conditioning the requirement to establish a monitoring range
as part of the Initial Compliance Status Report upon the
referencing subpart is inappropriate because the Initial
Compliance Status Report requirements are contained within
subpart SS. The commenter suggested that the phrase "if
required under a referencing subpart" be deleted from
§63.998 (c) (5) (ii) of the rule. This commenter also requested
that the final sentence of this paragraph be revised to
include a reference to the operating permit application "or
amendment."
Response: The EPA agrees with the commenter that
requirements of the Notification of Compliance Status should
be completely contained within subpart SS, and should not be
conditional upon requirements in a referencing subpart. The
final rule has been changed in accordance with this
commenter's suggestion. The EPA also agrees that it is
appropriate to refer to the "operating permit application or
amendment" rather than just the application, and the rule has
been revised accordingly.
Comment: One commenter (A-97-16, IV-G-01) stated that the-
requirement in §63.998 (c) (1) that "(the owner or operator)
subject to this subpart... keep the records specified in this
paragraph, as well as other records specified elsewhere in
this part" could be interpreted to mean any records specified
in 40 CFR. 63 must be kept whether they arc I'tjievciriL
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preparing summary tables of monitoring, recordkeeping, and
reporting requirements for subpart SS. These tables will
cross-reference the applicable regulatory text, and will
assist owners and operators in determining the requirement to
which they are subject.
Comment: Two commenters (A-97-17, IV-D-08; A-97-17, IV-D-
02) noted that §63.998(c)(1)(ii)(D) refers to a period "during
which excess emissions" but is not clear whether the excess
emissions occur or something else.
Response: Consistent with §63.998 (c) (1) (ii) (E) , the
phrase has been revised to state "during which excess
emissions occur."
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.998(c)(1)(ii)(D) and (E) should be revised to refer to
"...excess emissions as defined in paragraphs (c)(2)(iii) and
(c)(3)(iii) of this section" instead of "excess emissions as
defined in a referencing subpart."
Response: The commenter's suggested revisions of these
paragraphs are not appropriate. Section 63.998 (c) (2) (iii) and
(c)(3)(iii), to which the commenter believes the rule should
refer for the definition of excess emissions, describe
exceedances of parameter boundaries. Such exceedances
constitute excursions, which are different from excess
emissions. Excess emissions refers to the exceedance of a
known emission limitation, and this is defined in the
referencing subpart. For this reason, the change suggested by
the commenter is not appropriate, and no rule change has been
made regarding these provisions.
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.998(c) (1) (iii) should be deleted since it is redundant
with §63.998(b) (2) (ii) and §63.998(b) (3) (ii) .
Response: Because requirements for batch unit operations
were removed from subpart SS, §63.998(c)(1)(iii) was also
deleted, as it applied specifically to batch unit operations.
Consequently, the commenter's concern about redundancy between
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this requirement and that in §63.998(b)(2)(ii) and
§63.998 (b) (3) (ii) is no longer an issue.
Comment: One commenter (A-97-17, IV-D-02) stated that the
phrase "...with the permitting application..." in
§63.998 (c) (4) (i) and (c) (5) assumes that the operating permit
application will be filed after promulgation of this rule, but
before submitting the Initial Compliance Status Report (now
the Notification of Compliance Status report), which may not
be an appropriate assumption.
Response: The rule as proposed also includes the phrase
"... or as otherwise specified by the permitting authority..."
This phrase allows for the permitting authority to establish
how information or requests should be submitted if the
operating permit has already been submitted. The EPA believes
that this language permits various circumstances to be
adequately addressed, and that consequently, no rule change is
necessary.
Comment: One commenter (A-97-17, IV-D-02) stated that
since §63.998 (c) (5) requires a notification, it should be
moved from §63.998 to §63.999. The commenter suggests that the
new paragraph should be labeled §63.999(b) (10), and would also
result in cross-referencing changes throughout the rule.
Response: The commenter is correct that this is a
notification rather than a recordkeeping requirement. However,
because the requirement pertains specifically to monitoring of
different parameters than those specified in a referencing
subpart or subpart SS, the EPA considers this provision to be
primarily a monitoring requirement which overlaps with the
requirement proposed in §63.996(d). Thus, the EPA has revised
the rule to consolidate this requirement with that proposed in
§63.996(d), and cross-references throughout the rule have been
revised accordingly. The specific contents of a request to
implement alternative monitoring are listed in a new section
of the rule, §63.999(d). The intent of the rule, or
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requirements for owners and operators, are not altered by this
rule change.
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference to "periodic reports as specified in §63.999(b)" in
§63.998(d) (1) (iii) (F) is meaningless, because the commenter
believes that only §63.999(b)(1), which deals with routine
maintenance for storage vessel control systems, is pertinent
to closed vent systems and the associated recordkeeping
requirements are in §63.998(d)(2). Thus, the commenter
suggested that this paragraph be deleted or clarified.
Response: The reporting section of subpart SS has been
reorganized to consolidate the requirements for notifications
of compliance status and periodic reports. As a result, the
cross-reference mentioned by the commenter has been corrected
to §63.999(c).
4.13.4 Storage Vessel Records
Comment: One commenter (A-97-17, IV-D-02) requested that
a second sentence be added to §63.998(d) (2) (i) , stating, "This
information shall be submitted in the periodic reports as
specified in §63.999 (b) (4) ."
Response: The record kept in the §63.998(d)(2)(i) is of
the measured values of monitored parameters. The EPA does not
agree that it is necessary for this information to be
submitted in the periodic reports if the parameters were
within the specified parameter ranges. Instead, the owner or
operator should specify in the periodic reports required under
§63.999(c) that the measured values did not fall outside
parameter boundaries.
Comment: One commenter (A-97-17, IV-D-02) suggested that
§63.998(d)(2)(iii), which discusses the bypass provisions in
§63.983(a) for storage vessels routed to a process or fuel gas
system, be deleted in its entirety, since it is clear from
§63.982(a)(3) that §63.983 does not apply to storage vessels
routed to a process or fuel gas system.
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Response: The commenter is correct. Under the provisions
of §63.982, storage vessels routed to a process or fuel gas
system are subject to §63.984 and the monitoring,
recordkeeping and reporting requirements referenced therein,
and no other provisions. Thus, it is clear, as the commenter
stated, that §63.983 does not apply to these storage vessels,
and that the recordkeeping requirement in §63.998(d)(2) (iii)
is not relevant, this paragraph has been deleted from the
final rule.
4.13.5 Start-up , Shutdown, and Malfunction Records
Comment: One commenter (A-97-17, IV-D-02) wanted the
reference to "excess emissions as defined in a referencing
subpart" in §63.998(d)(3)(i) to be changed to "...as defined
in paragraph (b)(5)(ii)(D) of this section."
Response: The EPA has not made the commenter's suggested
revisions. Section 63.998 (b) (5) (ii) (D) defines excursions,
which are different from excess emissions. A definition for
excess emissions has been added to the final rule to clarify
that excess emissions are "emissions in excess of those that
would have occurred if there were no start-up, shutdown, or
malfunction and the owner or operator complied with the
relevant provisions of this subpart." Excess emissions refers
to the exceedance of a known emission limitation which would
be specified in a referencing subpart, whereas excursions
refer to the exceeding of a monitoring parameter boundary
which would be established under the requirements of 40 CFR
part 63 subpart SS, which is why it refers to the referencing
subpart for a definition.
4.13.6 3-Hour Averaging
Comment: One commenter (A-97-17, IV-D-08) requested that
the EPA change §§63.998 and 63.999 of the proposed rule to
allow an owner or operator to keep records and determine
excursions on a daily basis rather than on the proposed 3-hour
basis. The HON allows an owner or operator to keep records
and determine excursions on a daily basis and subpart SS
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requires that an owner or operator keep records and determine
excursions on a 3-hour basis.
The commenter explained that the reason for using daily
averages in the HON was to provide an opportunity for an owner
or operator to identify and fix problems with the process,
recovery device, or control device before being deemed
noncompliant (57 FR 62608, 62658).
The commenter (A-97-17, IV-D-08) also explained that the
use of a 3-hour average does not recognize and allow for
fluctuations in the monitored parameter. In the HON
promulgation BID, the EPA recognized the possibility of such
fluctuations, and felt that the use of a daily average would
mitigate the possibility that a source be deemed out of
compliance as a result of such a fluctuation.
The commenter stated that the Generic MACT approach
relies on the use of the HON as the basis for the proposed
requirements. The EPA has not offered any explanation for
either the increase in recordkeeping requirements or the
increased stringency of the compliance provisions as compared
to what was deemed achievable under the HON.
Response: The EPA evaluated the commenter's request and
has changed §§63.998 and 63.999 in the final rule to allow an
owner or operator to keep records and determine excursions on
a daily basis rather than on the proposed 3-hour basis. The
EPA has made the commenter's suggested change because the EPA
acknowledges that the Generic MACT approach relies on the use
of the HON as the basis of MACT and the compliance averaging
time required under the HON is linked with that determination.
The EPA does not intend for the daily averaging allowance to
be a default. The compliance averaging time is determined as
part of the MACT determination and future rules may not allow
for a daily averaging option.
4.13.7 Absorber Specific Gravity Monitoring
Comment: One commenter (A-97-17, IV-D-08) requested
that §§63.998(a) (3) (i) , 63.990 (c) (1), 63.993 (c) (1), and
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63.998 (a) (2) (ii) (C) (1) regarding the use of an absorber as a
final recovery device be modified to adequately address their
situation.
The commenter explained that when scrubbers use a fluid
containing a reactive chemical that is depleted during use,
e.g., caustic, monitoring of the specific gravity makes sense,
The commenter stated that they use fresh water as the
scrubbing fluid to scrub HAPs (primarily methylene chloride),
where the specific gravity between fresh water and methylene
chloride-saturated water is so small that it can not be
accurately measured.
The commenter provided data indicating that the speci-fic
gravity difference between fresh water and water saturated
with methylene chloride is approximately 0.005 specific
gravity units. The commenter stated that the proposal only
requires an owner or operator to measure the specific gravity
to the nearest .02 units and that measuring the specific
gravity of the scrubbing .fluid has no practical relevance in
their case.
Response: The EPA agrees with the commenter that
measuring the specific gravity of the scrubbing fluid has no
practical relevance for their specified case. It was the
EPA's intent to receive and consider comment on such cases.
The EPA has made changes to the promulgated rule that specify
that the specific gravity should not be monitored where the
een the specific crrcivity
scrubbing fluid and specific gravity of the fresh scrubbing
fluid is less than 0.02 specific gravity units. However, in
such cases, the final rule specifies that a continuous organic
monitoring device or a viable alternative monitoring parameter
capable of measuring organic HAP emissions must be used to
monitor compliance with the rule.
4.14 REPORTING REQUIREMENTS
4.14.1 Compliance Assessment Reports
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Comment: One commenter (A-97-17, IV-D-02) stated that
§63.999(a) (1) (i), which established general requirements for
performance test and flare compliance assessment notifications
and reports, should be revised to refer to flare compliance
demonstrations, as well as performance tests, throughout.
Response: The commenter"s suggested revision is in
keeping with the intent of the paragraph, as described by the
title of the paragraph. Thus, the EPA has revised this
paragraph to refer more generally to compliance
demonstrations, instead of performance tests, and to
explicitly include a reference to flare compliance
demonstrations.
Comment: One commenter (A-97-17, IV-D-02) asserted that
the results of compliance demonstrations conducted after
submission of the Initial Compliance Status Report should be
allowed to be submitted with the next periodic report, rather
than within 60 days, as specified in §63.999 (a) (1) (ii) . The
commenter also pointed out various other paragraphs that
should be modified if this change is made.
Response: The requirement that the results of compliance
demonstrations conducted after submission of the Initial
Compliance Status be submitted to the Administrator within 60
days is consistent with §65.164(b)(2) of the CAR, and with
requirements listed in §§63.7(g)(1), 63.9(h), and 63.10(d)(2)
of the General Provisions. The CAR contains exactly the same
requirement as subpart SS, while the General Provisions
requires that compliance demonstration results be submitted
with the Notification of Compliance Status, and that this
submission must occur within 60 days. While the EPA
appreciates that the commenter would prefer additional time to
submit the results and would prefer to include these results
with another report, the results of compliance assessments are
important information for the EPA to use in its determination
of owners and operators' compliance with regulatory
requirements. For this reason, and in order to be consistent
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with other regulations, this requirement in the rule has not
•been altered.
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §63.999(a) (2) (iii) (B) to "nonflare combustion
device" should be revised to "nonflare control device."
Response: The commenter is correct, because this
paragraph refers to performance tests for a broad range of
control devices, rather than just combustion and halogen
reduction devices, as implied by the proposed language. The
rule has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-02) stated that the
reference in §63.999(a) (2) (iii) (C) to "process vents" should
be revised to refer to "recovery devices."
Response: The commenter is correct. The paragraph in
question refers to recovery device monitoring records during
TRE index value determinations that must be submitted as part
of the compliance assessment report. The rule has been revised
accordingly.
4.14.2 Control Device Monitoring Reports
Comment: One commenter (A-97-16, IV-G-01) asserted that
the requirement in §63.999(b)(1)(ii) to include in the
periodic report the number of hours that the control system
did not meet the requirements from the current and previous
reporting periods is unnecessarily duplicative and burdensome
to the owner or operator. The commenter stated that EPA should
refer to earlier reports for information from previous
reporting periods.
Response: The EPA requires the information from current
and previous reporting periods in order to have in one
location a compiled historical record of the number of hours a
control system does mot meet requirements. This facilitates
the EPA's evaluation of compliance and assessment of a
source's performance. Furthermore, this provision in the rule
is consistent with a reporting requirement in §65.166 of the
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CAR. No rule change was made in response to the commenter's
concern.
Comment: A commenter (A-97-17, IV-D-02) asserted that
there is no benefit or purpose served by reporting anticipated
planned maintenance on storage vessel control devices, and
that this provision in §63.999(b)(1)(iii) should therefore be
deleted.
Response: The EPA has made no rule change in response to
this comment. The EPA believes that the information provided
by reporting anticipated planned maintenance on storage vessel
control devices is important to the EPA's efforts to assess
compliance and source performance. Furthermore, the provision
as written is consistent with.§65.166 of the CAR.
Comment: One commenter (A-97-17, IV-D-02) stated that the
following subparagraph should be added to §63.999 (b) (5) :"(iv)
The owner or operator shall notify the Administrator in the
Initial Compliance Status Report or, if the Initial Compliance
Status Report has already been submitted, in the Periodic
Report specified in paragraph (b)(6) of this section
immediately preceding implementation of the alternative
recordkeeping requirements of §63.998(b)(5)."
Response: The commenter's suggested change is
appropriate, as it places in the reporting section of the rule
a reporting requirement that is referred to in §63.998(b)(5).
It is important that all reporting requirements be specified
in §63.999, the reporting section of subpart SS, so that
owners and operators can accurately determine their
obligations. For this reason, the rule revision suggested by
the commenter, with changes to reflect other revisions to the
rule, has been added to §63.999 (b) (5).
Comment: A commenter (A-97-17, IV-D-02) suggested that
the following subparagraph should be added to §63.999(b) (6):
"(iii) The owner or operator shall notify the Administrator in
the Initial Compliance Status Report specified in paragraph
(b) (5) of this section or, if the Initial Compliance Status
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Report has already been submitted, in the Periodic Report
immediately preceding implementation of the alternative
recordkeeping requirements of §63.998(b) (5). The notifications
specified in §63.998 (b) (5) (ii) shall be included in the next
Periodic Report following the identified event."
Response: As discussed in the response to the previous
comment, the commenter's suggested change is appropriate, as
it places in the reporting section of the rule a reporting
requirement that is referred to in §63.998(b)(5). It is
important that all reporting requirements be specified in
§63.999, the reporting section of subpart SS, so that owners
and operators can accurately determine their obligations. For
this reason, the rule revision suggested by the commenter,
with changes to reflect other revisions to the rule, has been '
added to §63.999 (c) (6) (iv) .
Comment: One commenter (A-97-17, IV-D-02) suggested that
a new paragraph (b)(11) be added to §63.999, and that it
state: "Requests for approval of an alternative monitoring
method, as specified in §63.998 (c) (4) shall be included in the'
operating permit application or as otherwise specified by the
permitting authority." The commenter suggested a related
cross-referencing change to §63.998 (c) (4) (i) .
Response: The EPA does not agree with the commenter's
suggestion, as it is entirely redundant with §63.998 (c) (4),
and it is not a report or a notification. Thus, there is no
reason to add this paragraph to §63.999.of the iule, which
governs reporting requirements, and no rule change was made.
Furthermore, as discussed in the response to a previous
comment, the provisions of §63.998 (c) (4) have been moved to
63.996(d), governing monitoring alternatives, and §63.999(d),
which establishes the content for requests to implement
monitoring alternatives.
Comment: One commenter (A-97-17, IV-D-02) stated that
the cross-references in §§63.988(c) (2), 63.989 (c) (2),
63.990(c) (2), 63.992(c) (2), 63.993 (c) (5), 63.994 (c) (3),
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63.995 (c) (2) to the information required in §63.999 (b) (3)
should be changed to §63.999 (b) (5). In each of these cases,
the rule states, "In order to establish the range (for
monitored parameters), the information required in
§63.999(b) (3) shall be submitted in the Initial Compliance
Status Report..."
Response: The reporting section of the rule was revised
to consolidate requirements for the Notification of Compliance
Status in §63.999(b). Because of this change, the cross-
referencing issue raised by the commenter has changed since
proposal. Correct cross-references to this reporting
requirement have been inserted in the paragraphs identified by
the commenter.
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5.0 NATIONAL EMISSION STANDARDS FOR EQUIPMENT LEAKS -
CONTROL LEVEL 1 (40 CFR PART.63, SUBPART TT)
5.1 DEFINITIONS
Comment: One commenter (A-97-17; IV-G-01) indicated that
terms used in the equipment leak provisions of Subpart TT
should be defined in §63.1001.
Response: The EPA has added clarifications and
definitions to §63.1001.
5.2 COMPLIANCE DETERMINATION
Comment: One commenter (A-97-17; IV-G-01) suggested
that, for the purpose of using an alternative means of
emission limitation, it may be unreasonable and costly to
require an owner or operator to demonstrate the emission
reduction achieved by a required work practice for 12 months.
The commenter stated that EPA should already know the emission
reduction achieved by the required work practice, and that the
owner or operator should only be required demonstrate the
emission reduction achieved by the proposed alternative work
practice. The commenter also noted that in
§63.1002 (b) (4) (ii), the term "equipment" is used rather than
"work t?ractice. "
Response: The EPA agrees with the commenter and the 12
month requirement, §63.1002 (b) (4) (ii), was removed from the
regulation. It is the operator's burden to provide sufficient
data to support an alternative work practice. The EPA has no
basis supporting the need for a minimum data requirement.
5.3 EQUIPMENT IDENTIFICATION
Comment: One commenter (A-97-17; IV-G-01) noted that the
equipment identification requirements in §63.1003 (e) should
not contain the provision that equipment designated as having
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no detectable emissions must have no external actuating
mechanism in contact with the process fluid. The commenter
noted several related sections in Subpart TT [§§63.1007(e)(2)
-- agitators with no external shaft, §63.1006 (e) (4) -- valves
designated for no detectable emissions, and
§63.1012(f) -- compressors designated for no detectable
emissions] that did not prohibit external actuating mechanisms
in contact with the process fluid. The commenter recommended
that §63.1003 (e) include language from §65.103 of the
Consolidated Air Rule in lieu of language in §§63.1003(e)(1)
through (3). The commenter also noted that other sections
should be revised as follows: (1) Section 63.1017 (b) (4) should
read: "As specified in §63.1003(e), the owner or operator
shall maintain the identity of compressors operating with an
instrument reading of less than 500 parts per million."
(2) Section 63.1017(c)(1) should read: "For valves, the owner
or operator shall maintain the records specified in paragraphs
(c) (1) (i) through (c) (1) (iii) of this section. (i)
(ii) For valves designated for no detectable emissions under
the provisions of §63.1007 (e) (2), record the dates and results
of each compliance test as specified in §63.1006(e) (4) (i) (2)."
Response: The EPA has not made the changes suggested by
the commenter. Subpart TT was developed to parallel the base
leak detection and repair programs of 40 CFR part 60,
subpart V and 40 CFR part 61, subpart W. The suggested
provision changes to 40 CFR part 63, subpart TT would create a
deviation from those base programs. The EPA may allow an
owner or operator of an affected source under the generic MACT
rule the option of complying with either subpart TT or
subpart UU of 40 CFR part 63. The EPA has provided this
option so that an owner or operator that is already complying
with provisions similar to 40 CFR part 60, subpart V or 40 CFR
part 61, subpart W would not have to change their existing
LDAR program. The suggested revisions to subpart TT could
cause confusion and burden for an owner or operator who has
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already developed monitoring and recordkeeping regimens to
comply with these other subparts. The EPA developed the
40 CFR part 63 subpart TT "standard standard" in order to
streamline the NSPS requirements so they did not want to
deviate too much from those requirements and the "standard
standard."
Comment: One commenter (A-97-17; IV-G-01) stated that
the three percent limit imposed on difficult-to-monitor valves
should be clarified. The commenter asserted that the three
percent limit should only be applied to new sources. The
commenter supplied recommended language to address their
comment.
Response: To be consistent with subpart H of the HON,
EPA revised the language in §63.1003 to include a 3 percent
limit on the number of valves that can be designated as
difficult-to-monitor at new or reconstructed sources, and to
impose no limit on the number of difficult-to-monitor valves
at existing sources. It is appropriate to limit new sources
because designers can consider equipment layout when designing
a new source.
5.4 LEAK REPAIR
Comment: One commenter (A-97-17; IV-G-01) suggested that
the leak identification removal requirement in §63.1005 (b) (1)
for valves and connectors be revised to apply only to valves
and connectors in gas/vapor or light liquid service. The
commenter pointed out that, according to §63.1010(b), no
monitoring is required for valves and connectors in heavy
liquid service if a leak detected by auditory, visual or
olfactory inspection is eliminated within 5 days.
Response: The EPA agrees with the commenter and has
revised §63.1005(b)(1) to apply only to valves and connectors
in gas/vapor or light liquid service. However, it was the
EPA's intent to have all leaking equipment identified.
Therefore, §63.1010 (b) (2) was changed to require
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identification of leaking equipment i.e., equipment with an
instrument reading of 10,000 part per million.
Comment: One commenter (A-97-17; IV-G-01) suggested that
subpart TT should include language that addresses what is and
what is not considered a violation when attempting to repair a
leak, similar to language in §63.162 (h) of subpart H (HON
equipment leaks). The commenter pointed out that §63.162(h)
of the HON states that if an attempt to repair a leak is made
within the specified time, but.the attempt is unsuccessful,
the owner or operator is not in violation of the HON. The
commenter expressed concern that successful repair of a leak
may require multiple attempts and that applicable State
regulations and permit conditions may prevent an owner or
operator from designating the leaking piece of equipment for
delay of repair. The commenter suggested that similar
language be included in §63.1005 which would clarify that
failing to take action upon discovering a leak is violation,
but that good-faith, unsuccessful attempts at repair are not
violations.
Response: Subpart TT contains language that clarifies
that leaks, in and of themselves, are not considered
violations of the standard. The standards require action upon
detecting leaks, such as repair and recordkeeping
requirements. Failing to take the required actions are
violations of the standards; detecting a leak is not a
violation of the standards. Therefore, it is not necessary to
add language from the HON to Subpart TT to clarify this issue.
If it is necessary to delay repair beyond the required repair
time, the source can employ the delay of repair provisions. A
source that neither repairs a leak nor uses the delay of
repair provisions is in violation.
5.5 VALVES IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE
Comment: One commenter (A-97-17; IV-G-01) requested that
valve monitoring language from §§61.242-7(c)(1) and
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60.482(b) (3) (ii) (A) be used in lieu of language in
§63.1006 (b) (3) (ii) (A). The commenter stated that the
requirements for "same month" monitoring place an undo burden
on the monitoring system and assume that a quarterly period is
a calendar quarter. The commenter maintains that a quarterly
period is a combination of 3 months dependent on when the rule
becomes effective. The commenter recommended that the EPA be
consistent with other similar subparts.
. Response: The language "(first, second, or third month)"
clarifies that all equipment need not be monitored in the same
month within a 3 month period. That is, the plant may stagger
the monitoring of valves,' connectors, etc., across the 3 month
period as long as subsequent monitoring of individual
components occurs every 3 months. It is not the intent of the
language to require the 3 month period coincide with calendar
quarters.
5.6 PUMPS IN LIGHT LIQUID SERVICE
Comment: One commenter (A-97-17; IV-G-01) stated that
there is no reason to require the calculation of percent
leaking pumps in Subpart TT. The commenter noted that there
is no QIP requirement and that the semi-annual report does not.
require this information. The commenter recommended that
§63.1007 (c) be deleted. This commenter also noted that if the
EPA retains this requirement, then §63.1007 (c) (2) should be
revised to apply only to continuous process units within 1
month after startup (delete the "or" in this phrase) and the
PL calculation should exclude pumps found to be leaking by a
visual inspection under §63.1007(b)(3).
Response: The EPA agrees with the commenter that
§63.1007 (c) should be deleted, therefore it has been deleted
in the promulgated rule.
5.7 ENCLOSED-VENTED PROCESS UNITS
Comment: One commenter (A-97-17; IV-G-01) recommended
that the enclosed-vented process unit provisions in §63.1016
be revised to allow for either a process unit or a portion of
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a process unit to be designated as an enclosed-vented process.
The commenter also requested that enclosed-vented process
units be given the option to be routed to a fuel gas system or
to a process. In addition, the commenter suggested that
enclosed-vented process units should not be exempt from the
closed vent system requirements of § 63.1015.
Response: The EPA notes that the enclosed-vented process
unit alternative is intended for process units entirely
contained within large buildings, where all emissions will
vent through a limited number of exhaust ports. Many of these
process units are unmanned. Pharmaceutical processors are
typical examples of this type of operating scenario.
The EPA maintains that it is inappropriate to allow the
enclosed-vented alternative for portions of process units.
Doing so creates confusing compliance situations and stretches
the scope of the allowance beyond what was originally
intended.
5.8 GENERAL
Comment: One commenter (A-97-17, IV-G-01) suggested that
all references made in subpart TT to compliance with the
provisions of subpart SS should be revised to refer instead to
§63.1015, which governs closed vent systems and control
devices, or emissions routed to a fuel gas system or process,
so that no requirements are overlooked.
Response: The commenter is correct, and the final rule
has been revised to make this change. By referencing §63.1015,
the EPA ensures that the appropriate requirements for closed
vent systems and control devices, or emissions routed to a
fuel gas system or process are met by the owner or operator
subject to these provisions. Section 63.1015 itself cross-
references subpart SS, and this cross-reference has been
maintained in the final rule, as subpart SS holds the detailed
requirements that must be met.
Comment: A commenter (A-97-17, IV-G-01) stated that
references to the monitoring method requirements in each
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equipment section are incorrect and inconsistent. Sometimes
both paragraphs (b) and (c) are referred to, while at other
times only paragraph (b) is referenced. The commenter said
that all of these references should be consistent, and should
either refer to §63.1004(b), or §63.1004 (b) and (c) .
Response: The commenter is correct about the need for
consistency and accuracy in cross-referencing monitoring
method requirements. Section 63.1004 (b) addresses instrument
monitoring methods for leak detection and §63.1004 (c)
addresses instrument monitoring using background adjustments,
which is optional, at the owner or operator's discretion.
Therefore, the EPA has revised the rule to refer to the
monitoring requirements of "§63.1004 (b) and, as applicable,
(c)."
5.8.1 Applicability
Comment: One commenter (A-97-16, IV-D-01) stated that
since the referencing subpart controls what equipment is
regulated and subpart TT governs how the equipment is
regulated, §63.1000 (b) and the definition of "equipment" in
§63.1001 should be deleted from the rule.
Response: The EPA agrees with the commenter that the
designation of applicability belongs in Subpart YY.
Appropriate changes have been made to both Subparts YY and TT.
5.8.2 Definitions
Comment: One commenter (A-97-17, IV-G-01) wondered why
there was no explanation in the preamble as to why both of Lhe
terms "relief device or valve" and "pressure relief device or
valve" are needed. The commenter thought that, consistent with
the CAR, "relief device or valve" is intended to include
relief valves that do not relieve pressure, and stated that if
this is the case, the definition of relief device or valve
should mention those relief valves that let in nitrogen to
prevent vacuums.
Response: The commenter is correct that the EPA intended
the use of these definitions in subpart TT to be consistent
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with their use in the CAR. Therefore, the EPA has revised the
definition of "relief device or valve" in accordance with the
commenter's suggestion, and the definition in the final rule
includes relief valves that let in nitrogen to prevent
vacuums.
Comment: One commenter (A-97-16, IV-D-01) stated that
all references to subpart SS in the definition of "repaired"
should be deleted, and a definition of this term should be
added to subpart SS.
Response: The commenter is correct, and the EPA has
added a definition of "repaired" to subpart SS and removed the
references to subpart SS in the definition of "repaired" found
in subpart TT. In addition, the EPA has added a definition of
"first attempt at repair" to subpart SS, as this term, as well
as the term "repaired," is used in subpart SS and was not
defined in the proposed rule.
5.8.3 Compliance assessment
Comment: One commenter (A-97-17, IV-G-01) stated that
§63.1002(b), provisions for alternative means of emissions
limitation, should be revised to include the performance
standard exemption that is in subpart UU. The commenter
further stated that if the designation of valves as having no
detectable emissions is considered a performance standard,
then valves should be included in the exemption.
Response: The commenter is correct about including the
performance standard exemption in §63.1002(b), and is also
correct that the designation of valves as having no detectable
emissions is considered a performance standard. Accordingly,
the EPA revised the final rule to include a performance
standard exemption which specifies that the alternative means
of emission limitation provisions do not apply to the
performance standards for pressure relief devices, valves
designated as having no detectable emissions, or compressors
operating under the alternative compressor standards.
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Comment: One commenter (A-97-17, IV-G-01) stated that
references to §§63.1002 (b), 63.1005(c), and 63.1016 are
inconsistent throughout the rule. This commenter asserted that
the "leak detection" part of each section should reference
§§63.1002 (b) and 63.1016, and that §63.1005(c) should only be
referenced in the "leak repair" part of each section. The
commenter listed the following paragraphs where this is
necessary: §§63.1006 (b), 63.1007(b), 63.1008(b), 63.1009(b),
63.1010(b), 63.1011(b), 63.1012(b), 63.1013(b), and
63.1014 (b) . This is similar to a comment on analogous
provisions of subpart UU.
Response: The commenter is correct regarding the need
for consistent referencing of exemptions throughout the rule.
The commenter is also correct regarding the appropriate
placement of exemptions on the leak detection parts of the
rule and delay of repair conditions in the leak repair parts
of the rule. The EPA has revised the final rule accordingly,
and the leak detection parts of each section of the rule
include the exemptions provided under §63.1002 (b) (Alternative
means of emission limitation), §63.1016 (Alternative means of
emission limitation: Enclosed-vented process units), and
within the respective sections of the rule (e.g. the special
provisions for pumps found in §63.1007(e)). Furthermore, the
references to delay of repair exceptions have been revised to
appear only in the leak repair parts of the sections in the
final rule,- as these are not relevant to the leak detection
requirements found in the rule.
5.8.4 Equipment Identification
Comment: One commenter (A-97-17, IV-G-01) stated that the
reference in §63.1003 (b) (1) to the initial survey required by
§63.1008 (a) (1) (I) is incorrect, and that this final sentence
should be deleted, since there is no initial survey required,
and this section does not exist.
Response: The EPA agrees with the commenter; the
sentence was deleted.
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Comment: One commenter (A-97-17, IV-G-01) pointed out
that §63.1003 (c) (3), which establishes provisions for the
identification of unsafe or difficult-to-monitor equipment, is
redundant with requirements in §§63.1003 (c) (4), which also
addresses the identification of such equipment, and
63.1003 (c) (5), which establishes requirements for a written
plan. The commenter suggests that paragraph (c)(3) be deleted
and paragraphs (c) (4) and (c) (5) be renumbered.
Response: As indicated by the commenter, §63.1003(c)(3)
is entirely redundant with paragraph(c)(4) of the same
section. The provisions found in paragraph (c) (3) are repeated
in their entirety in (c)(4), and thus, the EPA deleted and
reserved §63.1003 (c) (3) in the final rule. This paragraph was
reserved in order to eliminate the need for renumbering and
the possibility of cross-referencing errors.
Comment: The commenter (A-97-17, IV-G-01) stated that
the written plan requirements under §63.1003 (c) (5) establish
monitoring provisions for unsafe-to-monitor equipment.
However, §63.1008 does not require periodic monitoring for
connectors in gas/vapor or light liquid service. Monitoring is
only required if evidence of a potential leak is found. Thus,
the commenter claimed that the written plan requirements of
.§63.1003(c)(5) should not apply to unsafe-to-monitor
connectors.
Response: The EPA agrees with the comment and has
removed the requirement that unsafe-to-monitor connectors be
included in the written plan requirements of §63.1003(c) (5).
5.8.5 Instrument and Sensory Monitoring for Leaks
Comment: One commenter (A-97-17, IV-G-01) stated that
language in subpart YY explaining what to do if the initial
compliance date occurs after the beginning of a standard
calendar period should be added to §63.1004 of subpart TT.
Response: The EPA does not agree with the commenter's
recommendation that provisions addressing the circumstances
when the initial compliance date occurs after the beginning of
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a standard calendar period should be included in subpart TT.
Instead, the EPA believes that it is appropriate to address
this issue in the referencing subpart, which is why this
language is included in subpart YY. .Furthermore, there is no
need for this information to appear in more than one location.
The referencing subpart will establish initial compliance
dates for the sources it regulates, and thus it is appropriate
that issues regarding this initial compliance date would also
be addressed in the referencing subpart. The EPA has made no
rule change in response to this comment.
Comment: One commenter (A-97-17, IV-G-01) stated that
while §63.1004(a) (2) (ii) requires monitoring pursuant to
§63.1008(d)(2), there are in fact no inspection requirements
in §63.1008(d)(2) for inaccessible, ceramic, or ceramic-lined
connectors. Section 63.1008(d)(2)(ii) requires repair if leaks
are found by auditory, visual, or olfactory means. The same
commenter pointed out that while §63.1004(a) (2) (iv) requires
monitoring for pumps, valves, agitators and connectors in
heavy liquid service; instrumentation systems; and pressure
relief devices in liquid service, these components do not in
fact need to be visually inspected. The commenter explained
that §63.1010 (b) (1) only requires monitoring if an auditory,
visual, or olfactory leak is found, and this requirement
should be cross-referenced in §64.1004 (a) (1).
Response: The commenter is correct regarding inspection
requirements for inaccessible, ceramic, or ceramic-lined
connectors and for pumps, valves, agitators and connectors in
heavy liquid service; instrumentation systems; and pressure
relief devices in liquid service. Thus, the EPA has deleted
the provisions of the proposed §63.1004(a)(2)(ii) and
§63.1004 (a) (2) (iv) from the final rule, and reserved the
paragraphs.
Comment: One commenter (A-97-17, IV-G-01) stated that
water is usually given as an example of an inert, and the
commenter recommended adding this example to the phrase found
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in §63.1004 (b) (2): "For process streams that contain nitrogen,
air, or other inerts that are not organic HAP."
Response: The commenter's requested change has been made
in the final rule, and water is included in §63.1004 (b) (2) as
an example of an inert that is not an organic HAP. This does
not change the intent of the regulation, but the EPA believes
that if this revision is helpful to the owner or operator,
then it is beneficial and appropriate.
Comment: Section 63.1004(b)(6) addresses monitoring data
obtained prior to the source becoming subject to the standard
and its use to qualify for less frequent monitoring, and the
commenter (A-97-17, IV-G-01) states that the reference to
§63.1008 in this paragraph should be deleted, since connectors
are not subject to periodic monitoring requirements.
Response: The commenter is correct, and the reference to
§63.1008 has been deleted accordingly.
Comment: The commenter (A-97-17, IV-D-02) states that
language in §§63.1004(c)(3) governing monitoring should read
"within one centimeter" rather than "as close to the interface
as possible" for monitoring of moving components such as pumps
and compressors.
Response: The EPA has revised this paragraph in the
final rule to remove the phrase "as close to the interface as
possible." Instead, this paragraph will refer simply to
Method 21 of 40 CFR part 60, appendix A, for requirements on
how monitoring should be conducted.
Comment: The commenter (A-97-17, IV-G-01) states that
since §63.1006(e)(4) allows the owner or operator to designate
valves as having no detectable emissions, §§63.1004(c) and
(c)(4) also need to reference NDE valves.
Response: The EPA interprets the comment to mean there
should be a provision to allow for adjustment of the Method 21
parts per million reading to account for background. The EPA
disagrees with the comment. The no detectable emission
definition of 500 parts per million is not supported by
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rigorous data analysis but was based on 5% of the leak
definition. This threshold level is reasonable as a basis for
selecting valves for which "leak" detection would provide
little to no benefit. There's no technical basis for refining
the 500 parts per million threshold.
Comment: Section 63.1004 (e) (2) requires that when a leak
is detected, the information in paragraphs (e)(2)(i) and (ii)
be recorded and kept. The commenter (A-97-17, IV-G-01) stated
that paragraphs (e)(2)(i) and (ii) should be deleted, and the
reference should instead be to §63.1005(e), Leak repair
records, because this contains a more complete list of the
information that needs to be recorded and retained.
Response: The commenter is correct. The list of
information required to be kept under §§63.1004 (e) (e) (i) and
.(e) (2) (ii) when a leak is detected is a subset of the
information listed in §63.1005 (e), Leak repair records. The
EPA has revised §§63.1004 (e) (2) (i) and (e) (2) (ii), and the
cross-referencing in §63.1005(e).
5.8.6 Leak Repair
Comment: Section 63.1005 (c) (3) (ii) requires that purged
material be collected and destroyed or recovered in a control
device complying with subpart SS after repair. The commenter
(A-97-17, IV-G-01) stated that the option of routing the
purged material to a process or fuel gas system should be
added. The commenter also asserted that the reference to
subpart SS should be changed to §63.1015 ot §63.1002(b).
Response: The commenter's assertion that
§63.1005 (c) (3) (ii) should allow for the option of routing
purged material to a fuel gas system or process is a valid
one, and the EPA has added this option to the final rule.
Also, in accordance with changes made throughout the rule to
refer to §63.1015 (Closed vent systems and control devices; or
emissions routed to a fuel gas system or process standards)
instead of to subpart SS, it is also appropriate that this
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provision require compliance with the requirements of §63.1015
or §63.1002(b) , Alternative means of emission limitation.
Comment: The commenter (A-97-17, IV-G-01) stated that
paragraphs (d)(1) and (d)(2) of §63.1005 should be deleted,
since they repeat criteria already'referred to in §63.1003(d)
regarding unsafe-to-repair connectors.
Response: Section 63.1005(d) addresses unsafe-to-repair
connectors "as described in §63.1003(d)," and then
subparagraphs (d)(1) and (d)(2) restate the criteria listed in
§63.1003(d) for designation as unsafe-to-repair. The commenter
is correct that §§63.1005(d)(1) and (d)(2) are redundant with
the provisions of §63.1003(d), and the EPA has deleted these
paragraphs from the final version of the rule.
5.8.7 Valves in Gas and Vapor Service and in Light Liquid
Service Standards
Comment: The commenter (A-97-17, IV-G-01) requested
clarification of the EPA's intent in §63.1006(b) (6) (iii) . The
commenter assumed that if the percentage of leaking valves
exceeds 2 percent, then monthly monitoring must be
implemented. If, after two months, the percentage of leaking
valves is 2 or less, the process unit can revert to skip
monitoring, and no further notification is required.
Response: This language is identical in content to 40
CFR Part 60 Subpart W §60.483-2. The EPA will interpret this
language consistent with interpretations of 40 CFR Part 60
Subpart W.
Comment: The commenter (A-97-17, IV-G-01) stated that
the language in §§63.1006 (e) (1) and (2) is confusing and
redundant and should be revised. Specifically, the commenter
identifies the following sentence in §63.1006 (e) (1) as
troublesome: "Any valve that is designated...as an unsafe to
monitor valve, and the owner or operator monitors the valve
according to the written plan...is exempt from the monitoring
requirements of paragraph (b)...and the owner or operator
shall monitor the valve according to the written plan." The
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analogous sentence, discussing difficult-to-monitor valves, in
§63.1006 (e) (2) is also identified as being confusing and
redundant. The commenter provides specific suggestions drawn
from language in subpart UU which has analogous provisions.
Response: While the commenter is correct regarding the
confusing language in these paragraphs, the revisions
suggested by the commenter were not consistent with one
another. Since these are parallel provisions, it is
appropriate that the language governing these provisions also
be parallel. Consequently, the EPA revised both paragraphs to
exempt unsafe and difficult-to-monitor valves from monitoring
requirements in §63.1006 (b), and to require them to monitor
according to the written plan specified in §63.1003 (c) (5). The
revised language is shown below:
"(I) Unsafe-to-monitor valves. Any valve that is
designated, as described in §63.1003 (c) (1) , as an
unsafe-to-monitor valve, is exempt from the
monitoring requirements of paragraph (b) of this
section, and" the owner or operator shall monitor the'
valve according to the written plan specified in
§63.1003(c) (5) .
(2) Difficult-to-monitor. Any valve that is
designated, as described in §63.1003 (c) (2), as a
difficult-to-monitor valve, is exempt from the
requirements of paragraph (b) of this section, and
the cv.'ncr or operator shall ruomtOi Llie valve
according to the written plan specified in
§63.1003 (c) (5) ."
Comment: One commenter (A-97-17, IV-G-01) stated that, as
written, §63.1006 (e) (4) (ii) implies that if a valve has ever
had an instrument reading above 500 ppm, it can no longer be
designated as having "no detectable emissions." The commenter
asserted that this eliminates any incentive to upgrade a
valve, and that this sentence should therefore be deleted. The
commenter further observed that this sentence is not in NESHAP
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subpart V or NSPS subpart W, and noted that the same sentence
is included for compressors in the CAR, and the CAR's preamble
makes it clear that if an instrument reading of 500 ppm or
greater is detected for a compressor designated as operating
below 500 ppm, the compressor is in violation of the standard.
Response: The EPA's designation of "no detectable
emissions" is included to eliminate monitoring of valves for
which there is little to no benefit of monitoring for leaks.
Obviously, if a particular valve exceeds the threshold limit
then there exists a potential benefit to monitoring. The
provision in §63.1006 (e) (4) (ii) does not preclude plants from
replacing valves with better valves which meet the criteria of
"no detectable emissions."
5.8.8 Pumps in Light Liquid Service Standards
Comment: One commenter (A-97-17, IV-G-01) observed that
§63.1007(e) (1) (v) incorrectly requires that if there are
visual indications of liquids dripping at the weekly
inspection, the owner or operator must comply with
§63.1007(e)(1)(v)(A) or (B). Instead, the commenter stated,
(A) and (B) should be combined into a single statement,
similar to the language -in §63.1026 (e) (1) (v) (A) of subpart UU.
Alternatively, the commenter stated that the reference could
be to §63.1007 (e) (1) (v) (A) and (B) or (C), or (A) through (C)
could be deleted entirely and replaced with language taken
from §§63.1007(b)(3) and (b)(4).
Response: The commenter is correct that the provisions
as proposed are incomplete. While §63.1007(e)(1)(v) requires
the owner or operator to comply with §63.1007(e) (1) (v) (A) or
(B) if there are visual indications of liquids dripping at the
weekly inspection, there is also a §63.1007(e)(1)(v)(C) which
is not addressed. The EPA has revised these provisions in
accordance with the approach used in subpart UU. In this case,
(A) and (B) have been combined into one paragraph, (A).
Section 63.1007(e) (1) (v) (C) became §63.1007 (e) (1) (v) (B) and
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the owner or operator is required to comply with either (A) or
(B) .
Comment: One commenter (A-97-17, IV-G-01) stated that in
§§63.1007 (e) (2) and (e) (3) the exemption from the "monitoring
requirements of paragraph (b)" for pumps with no external
shaft or pumps routed to a process or fuel gas system or
equipped with a closed vent system to a control device, is
incomplete. The commenter stated that such pumps should also
be exempt from the weekly visual inspection requirements of
paragraph (b), and the paragraph should be revised to state
"...exempt from the requirements of paragraph (b) of this
section." The commenter stated that this would be consistent
with the HON subpart H, NSPS subpart W and NESHAP subpart V.
Response: The commenter is correct and the EPA has
revised the rule to indicate that pumps with no external
shafts, or pumps routed to a process or fuel gas system or
equipped with a closed vent system to a control device, are
exempt from all of the requirements of §63.1007 (b).
Comment: The commenter (A-97-17, IV-G-01) stated that
unsafe-to-monitor pumps should be exempt from paragraphs (b)
through (d) of this section, not just (b) as stated in
§63.1007 (e) (5). The commenter also recommended that the
exemption from "the repair requirements of §63.1005" be
deleted, since it contradicts the requirement within the
written plan of §63.1003 (c) (5), which is also referenced.
Rp.gponse: In response to this comment the EFA Devised
the proposed language to read as follows:
"Any pump that is designated, as described in
• §63.1003 (c) (1), as an unsafe-to-monitor pump is exempt
from the monitoring requirements, of paragraph (b) of this
section. The owner or operator shall monitor the pump
according to the written plan specified in
§63.1003(c) (5) ."
5.8.9 Connectors in Gas and Vapor Service and in Light
Liquid Service Standards
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Comment: One commenter (A-97-17, IV-G-01) pointed out
that the final sentence of §63.1008 (b) is redundant with the
leak repair provisions of §63.1008 (c). Furthermore, the
commenter stated that the leak detection sections for other
components do not reference the identification requirement
under §63.1004 (e) .
Response: The commenter is correct on both counts. For
the sake of consistency, the final sentence of §63.1008(b) was
deleted from the promulgated rule, and no further change was
made.
Comment: Section 63.1008(d)(2) provides that
inaccessible, ceramic, or ceramic-lined connectors are exempt
from the monitoring requirements of §63.1008(b), the
recordkeeping requirements of §63.1017, and the reporting
requirements of §63.1018. One commenter (A-97-17, IV-G-01)
asserted that these connectors should also be exempted from
the leak repair requirements of paragraph (c) of this section,
since §63.1008(d) (2) (ii) establishes the timing or repair of
inaccessible connectors.
Response: Paragraph (c) of §63.1008, the leak repair
paragraph, specifies what must be done if a leak is detected
pursuant to paragraph (b). Inaccessible, ceramic, or ceramic-
lined connectors are exempt from paragraph (b), leak
inspection requirements, so (c) does not apply either.
Furthermore, as the commenter states, §63.1008 (d) (2) (ii)
establishes repair requirements. Specifically, this paragraph
states that if a leak is observed in these connectors, it
shall be repaired as soon as practical. Thus, the commenter
is correct, and the rule has been revised to include an
exemption to §63.1008 (c) for inaccessible, ceramic, or
ceramic-lined connectors.
5.8.10 Agitators in Gas and Vapor Service and in Light
Liquid Service
Comment: The commenter (A-97-17, IV-G-01) stated that
NSPS subpart W, NESHAP subpart V, and RCRA subpart BB do not
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regulate agitators. If Control Level 1 (subpart TT) is
supposed to be similar to these rules, the commenter asserted,
perhaps agitators should not be regulated in subpart TT
either.
Response: It is the EPA's intent that agitators be
regulated under subpart TT, and this has not been changed in
the final rule. Because many owners and operators are already
subject to leak detection and repair requirements, the EPA
chose to allow owners or operators to comply with either
subpart TT or subpart UU. In this way, the owner or operator
would not have to change an existing leak detection and repair
program in order to comply with the requirements of the
generic MACT. This was an effort to reduce regulatory burden
associated with switching from one work practice to another
when there is little evidence of environmental benefit.
5.8.11 Compressor Standards
Comment: Section 63.1012 (g) provides an exemption for
reciprocating compressors that become an affected facility
under 40 CFR 60.14 or 60.15 of subpart W, provided that the
owner or operator demonstrates that recasting the distance
piece or replacing the compressor are the only options for
compliance. The commenter (A-97-17, IV-G-01) noted that the
references are in subpart A, not W. The commenter further
stated that unlike the RON, which gives such compressors an
extension, but requires that they comply, this paragraph
implies that the compressor is exempt from paragraphs (b),
(c), and (d) forever. The commenter sought confirmation that
this is true.
Response: The commenter is correct in noting that as
written the rule would not require control of reciprocating
compressors at facilities associated with these 4 source
categories. It was not the EPA's intent to exempt
reciprocating compressors. However, the EPA believes this to
be a moot point since the EPA is unaware of any reciprocating
compressors at the 10 major sources affected by the final
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rule. However, the language may be amended for future source
categories proposed for incorporation into Subpart YY if
reciprocating compressors are in use at their facilities.
5.8.12 Sampling Connection Systems Standards
Comment: One commenter (A-97-17, IV-G-01) stated that
§63.1013(c) should be amended to specify that the fuel gas
system or process in (c)(1) must be in compliance with the
requirements of §63.1015. The commenter also said that
paragraph (c)(2) should be deleted as it is a subset of
paragraph (c) (1) .
Response: To be consistent with other changes made to
the rule, §63.1013(c)(1) was revised to specify that a fuel
gas system or process to which purged process fluid is
returned must be in compliance with §63.1015 or §63.1002(b).
5.8.13 Closed Vent Systems and Control Devices; or
Emissions Routed to a Fuel Gas System or Process
Standards
Comment: One commenter (A-97-17, IV-G-01) recommended
that §§63.1015(b)(1) through (b)(3), which govern closed vent
systems and control devices, or emissions routed to a fuel gas
system or process, be revised to be similar to §63.172 (a)
through (c) of the RON, subpart H, while also incorporating
information particular to subpart TT. The commenter stated
that as proposed, the provisions are incomplete and
misleading. The commenter provided specific recommended
language, as follows:
"(b) Compliance standard. (1) Owners or .operators
routing emissions from equipment leaks to a fuel gas
system or process shall comply with the provisions
of subpart SS of this part, except as provided in
§63.1021(b).
(2) Owners and operators of closed vent systems and
control devices used to comply with provisions of
this subpart shall comply with the provisions of
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subpart SS of this part and (b)(2)(i) through
(b) (2) (iii), except as provided in §63.1021(b) .
(i) Nonflare control devices shall be designed and
operated to reduce emissions of regulated material
vented to them with an efficiency of 95 percent or
greater, or to an exit concentration of 20 parts per
million by volume, whichever is less stringent. The
20 parts per million by volume performance standard
is not applicable to the provisions of §63.1037.
(ii) Enclosed combustion devices shall be designed
and operated to reduce emissions of regulated
.material vented to them with an efficiency of 95
percent or greater, or to an exit concentration of
20 parts per million by volume, on a dry basis,
corrected to 3 percent oxygen, whichever is less
stringent, or to proved a minimum residence time of
0.50 seconds at a minimum temperature of 760°C.
(iii) Flares used to comply with this subpart shall
comply with the requirements of subpart SS of this
part."
Response:- After careful review of the proposed rule,
analogous provisions in the HON, and the commenter's suggested
revisions to the rule, the EPA decided to adopt the
commenter's suggested language and organization for this
paragraph. These changes, while not altering the intent or the
requirements of the rule, increase the clarity of iLs
provisions, thereby facilitating compliance by owners and
operators.
5.8.14 Recordkeepinq Requirements
Comment: Section 63.1017(c)(1)(ii) requires records for
valves added to or removed from a process unit if net credits
for removed valves are used. One commenter (A-97-17, IV-G-01)
asserted that the net credit language is not relevant, because
the credit is not applicable to the valve percent equation
being used. The commenter stated that §63.1017 (c) (1) (ii)
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should be replaced with the recordkeeping requirement in
§63.1006(e)(4)(i)(2) for valves with no detectable emissions.
Response: The commenter is correct. There is no other
reference in subpart TT to use of net credits. Furthermore,
the cross-reference to §63.1006(b)(6)(iv) has nothing to do
with net credits. Thus, the language was deleted.
Comment: One commenter (A-97-17, IV-G-01) stated that
§63.1017 (c) (3) should be deleted, because connectors do not
have to be monitored on a particular schedule.
Response: Section 63.1017 (c) (3) cross-references the
"monitoring schedule...as specified in §63.1008 (b)," which
requires that connectors shall be monitored within 5 days if
evidence of a potential leak is found. However, no periodic
monitoring is required, and therefore the commenter is
correct, and there is no "schedule" for monitoring. The EPA
has deleted this paragraph from the promulgated rule.
5.8.15 Reporting Requirements
Comment:' Sections 63.1018(a)(2)(ii)(B), (D), and (F)
requires that the Periodic Report include the number of
valves, pumps, or compressors, respectively, for which leaks
were not repaired. The commenter (A-97-17, IV-G-01) assumed
that this covers only those valves, pumps, or compressors that
missed the 5 day first attempt at repair or the 15 day repair
deadline, and not those covered by delay of repair provisions.
The commenter stated that equipment covered by the delay of
repair provisions will be reported under
§63.1018 (a) (2) (ii) (G) . The commenter requested clarification
of EPA's intent regarding these provisions.
Response: Section §63.1018 (a) (2) (ii) (B), (D), and (F)
require the reporting of the number of all valves, pumps, and
compressors which were not repaired. Section
§63.1018 (a) (2) (ii) (G) requires an explanation of each delay of
repair.
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6.0 NATIONAL EMISSION STANDARDS FOR EQUIPMENT LEAKS- - CONTROL
LEVEL 2 (40 CFR PART 63, SUBPART UU)
6.1 GENERAL COMMENTS
Comment: One commenter (A-97-17; IV-G-07) recommended
that Subpart UU allow the owner or operator to designate
sealless valves as operating with no detectable emissions, as
is allowed in 40 CFR part 60 subpart W and 40 CFR part 61,
subpart V. The commenter stated that allowing this
designation would provide an incentive for facilities to
install sealless valve technology. The commenter also noted
that facilities subject to subpart W and subpart V would
incur an increased monitoring burden if they had previously
designated some sealless valves as operating with no
detectable emissions. The commenter supplied suggested
modifications to regulatory text for the sections of UU that
would be affected by this change.
Response: The provisions in 40 CFR part 60, subpart W
and 40 CFR part 61, subpart V for designating valves as
operating with no detectable emissions require that the owner
or operator monitor these valves annually to verify that these
valves continue tc operate with no detectable emissions. The
extended monitoring periods and valve subgrouping provisions
of Subpart UU allow an owner or operator to monitor valves
even less frequently. The EPA expects that an owner or
operator would continue to have incentive to install advanced
valve technology, because these valves could be designated as
part of a subgroup, and could potentially be monitored as
infrequently as once every 2 years if the technology proves
effective. Therefore, EPA did not find it necessary to revise
Subpart UU as suggested by the commenter.
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6.2 APPLICABILITY
Comment: One commenter (A-97-17; IV-G-07) indicated that
terms used in the equipment leak provisions of Subpart UU
should be defined in §63.1020
Response: The EPA has added clarifications and
definitions to §63.1020.
6.3 ALTERNATIVE MEANS OF EMISSION LIMITATION
Comment: One commenter (A-97-17; IV-G-07) suggested that
it may be unreasonable and costly to require an owner or
operator to demonstrate the emission reduction achieved by an
alternative work practice for 12 months. The commenter
reasoned that EPA should already know the emission reduction
achieved by the required work practice, and that the owner or
operator should only be required to demonstrate the emission
reduction achieved by the proposed alternative work practice.
The commenter also noted that in §63.1021(d)(2)(ii), the term
"equipment" is used rather than "work practice."
Response: The EPA agrees with the commenter and the 12
month requirement, §63.1002 (b) (4) (ii), was removed from the
regulation. It is the operator's burden to provide sufficient
data to support an alternative work practice. The EPA has no
basis supporting the need for a minimum data requirement.
6.4 EQUIPMENT IDENTIFICATION
Comment: One commenter (A-97-17; IV-G-07) stated that
the three percent limit imposed on difficult-to-monitor valves
in §63.1022(c) (2) (i) (B) should be clarified. The commenter
asserted that the three percent limit should only be applied
to new sources. The commenter supplied recommended language
to address their comment.
Response: To be consistent with subpart H of the HON,
EPA revised the language in §63.1022 to include a 3 percent
limit on the number of valves that can be designated as
difficult-to-monitor at new or reconstructed sources, and to
impose no limit on the number of difficult-to-monitor valves
at existing sources. It is appropriate to limit new sources
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because designers can consider equipment layout when designing
a new source.
6.5 LEAK REPAIR
Comment: One commenter (A-97-17; IV-G-07) suggested that
the leak identification removal requirement in §63.1024 (c) (1)
for valves and connectors be revised to apply only to valves
and connectors in gas/vapor or light liquid service. The
commenter stated that, according to §63.1029 (b), no monitoring
is required for valves and connectors in heavy liquid service
if a leak detected by auditory, visual or olfactory inspection
is eliminated within 5 days.
Response: The EPA agrees with the commenter and has
revised §63.1024 (c) (1) to apply only to valves and connectors
in gas/vapor or light liquid service.
6.6 VALVES IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE
Comment: One commenter (A-97-17; IV-G-07) recommended
that unsafe-to-monitor and difficult-to-monitor valves be
exempted from the provisions in §63.1025(d)(2) which require •
follow-up monitoring 3 months after a leak is repaired. The •
commenter stated that it would be impractical and costly to
conduct follow-up monitoring within 3 months for
unsafe-to-monitor and difficult-to-monitor valves. The
commenter noted that such an exemption is provided in
§63.1027 (e) (1) where unsafe-to-monitor connectors are exempted
from the requirement for follow-up monitoring SO days after
repair.
Response: In order to remain consistent with the
provisions of §63.168(h) of the HON, §63.1025 (e) (1) has been
revised to state that unsafe-to-monitor valves are exempt from
the 3 month follow-up monitoring provisions of
§ 63.1025(d)(2). To remain consistent with §63.168(1) of the
HON, however, § 63.1025 (e) (2) has not been revised and
difficult-to-monitor valves continue to be subject to the
3 month follow-up monitoring provisions of §63.1025(d)(2).
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Difficult-to-monitor valves have some obstacle to
overcome before they can be monitored, but monitoring does not
pose a safety hazard. The written plan required for
difficult-to-monitor valves specifies annual monitoring at a
minimum. Because personnel are not put at risk and the valves
must be monitored at least annually, it is not appropriate to
exempt difficult-to monitor valves from the 3 month follow-up
monitoring upon repair of a leak.
Comment: One commenter (A-97-17; IV-G-07) expressed
concern with the wording in § 63.1025(c) (1) (i) which states
that "the owner or operator shall decide no later than the
implementation date of this part or upon revision of an
operating permit whether to calculate percent leaking valves
on a process unit or group of process units basis." The
commenter stated that the phrase, "group of process units
basis" in §63.1025(c) (1) (i), is confusing if it is intended to
refer to a subgroup of valves within a process unit. The
commenter suggested that the language be revised to read,
"...on a process unit or a valve subgroup basis."
Response: The intent of §§63.1025(b) and 63.1025 (c) is
to provide the owner or operator with maximum flexibility for
managing the monitoring of valves. The decision regarding
upon what to base the overall calculation and how to subgroup
are different. To be eligible for valve subgrouping
provisions, the owner or operator must demonstrate that less
than 2 percent of valves are leaking either within a process
unit or within a group of process units. If the owner or
operator decides to calculate the percentage of leaking valves
on a process unit basis, and less than 2 percent of the valves
are leaking within that process unit, then the valve
subgrouping provisions of §63.1025(b) apply to valves within
the process unit. If the owner or operator decides to
calculate the percentage of leaking valves on a group of
process units basis (more than one process unit), and less
than 2 percent of the valves are leaking within that group of
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process units, then subgroups of valves may be designated
within the group of process units (both within and across
individual process units). The owner or operator may decide
whether or not to group several process units together for the
purpose of calculating the percentage of leaking valves.
Section 63.1025 (c) (1) (i) specifies that this decision must be
made no later than the implementation date of this part or
upon revision of an operating permit.
6.7 PUMPS IN LIGHT LIQUID SERVICE
6.7.1 Calculation of PL and PT
Comment: One commenter (A-97-17; IV-G-07) suggested that
the definition of PT (the total number of pumps in regulated
material service) within the calculation of the percent
leaking pumps in §63.1026 (c) (4) be changed to explicitly :'
include.pumps routed to a process or fuel gas system or
equipped with a closed vent system routed to a control device.
The results of the equation in §63.1026 (c) (4) affect whether
or not a plant must implement a quality improvement program
(QIP). The commenter reasoned that if sealless pumps and dual
mechanical seal pumps can be included in the PT term, then a
plant should be given credit for pumps vented to a closed vent?
system routed to a control device or pumps routed to the
process or a fuel gas system.
Response: The EPA agrees with the commenter that the PT
term of the percent leaking equation in §63.1026(c)(4) should
include pumps routed to a process or fuel gas system 01
equipped with a closed-vent system. The definition of the PT
term in this section has been revised to include pumps meeting
the criteria in §63.1026 (e) (3), in addition to
paragraphs (e)(1) and (e)(2).
Comment: One commenter (A-97-17; IV-G-07) requested
clarification on how unsafe-to-monitor pumps should be
accounted for in the percent leaking pump calculation in
§63.1026(c)(4). The commenter inquired whether
unsafe-to-monitor pumps should be excluded from the PL term
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(the number of pumps found leaking as determined through
monthly monitoring) because they are not considered part of
the "monthly monitoring" of pumps. Also, the commenter
inquired whether unsafe-to-monitor pumps should be included in
the PT term (the total number of pumps in regulated material
service). The commenter (IV-G-01) reasoned that if the PL
term excludes unsafe-to-monitor pumps then the PX term should
exclude them as well. Similarly, the commenter noted that if
the PL term includes unsafe-to-monitor pumps, then they should
be included in the PT term.
Response: The PL term in §63.1026(c) (4) is defined as
the number of pumps found leaking as determined through
monthly monitoring as required in §63.1026(b)(1). The EPA
agrees with the commenter that the PL term does not include
unsafe-to-monitor pumps because they are not included in the
monthly monitoring required by §63.1026(b)(1). The PT term is
defined as the total number of pumps in regulated material
service, and therefore includes unsafe-to-monitor pumps in
regulated material service.
6.7.2 Sealless Pumps
Comment: One commenter (A-97-17; IV-G-07) suggested that
language in §63.1026 (e) (5) be revised to state that if more
than 90 percent of the pumps at a process unit are equipped
with dual mechanical seals or have no externally actuated
shaft (i.e. sealless pumps), then the process unit should be
exempt from the percent leaking calculation in §63.1026(c)
rather than being exempt from the leak detection requirements
in §63.1026(b). The commenter stated that this revision would
make Subpart UU consistent with §63.163(i) of the HON.
Response: The EPA agrees with the commenter, and EPA has
revised the language in §63.1026(e)(5) to state that if more
than 90 percent of the pumps at a process unit are either
equipped with dual mechanical seals or have no externally
actuated shaft then, the process unit is exempt from the
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percent leaking calculation in §63.1026 (c) and not exempt from
the leak detection requirements in §63.1026(b).
6.8 CONNECTORS IN GAS AND VAPOR SERVICE AND IN LIGHT LIQUID
SERVICE
Comment: One commenter (A-97-17; IV-G-07) suggested that
§63.1027 should include language that addresses what is and
what is not considered a violation when attempting to repair a
leak, similar to language in §63.162(h) of subpart H (HON
equipment leaks). The commenter pointed out that §63.162(h)
of the HON states that if an attempt to repair a leak is made
within the specified time, but the attempt is unsuccessful,
the owner or operator is not in violation of the HON. The
commenter expressed concern that successful leak repair may
require multiple attempts and that applicable State
regulations and permit conditions may prevent an owner or
operator from designating the leaking piece of equipment for
delay of repair. The commenter suggested that similar
language be included in subpart UU which would clarify that
failing to take action upon discovering a leak is violation,
but that good-faith, unsuccessful attempts at repair are not
violations.
Response: Subpart UU contains language that clarifies
that leaks, in and of themselves, are not considered
violations of the standard. The standard requires action upon
detecting leaks, such as repair and recordkeeping
requirements. Failing to take the required actions is d
violation of the standard; detecting a leak is not an inherent
violation of the standard. Therefore, the EPA believes that
it is not necessary to add the suggested language from the HON
to clarify this issue. If it is necessary to delay repair
beyond the required repair time, the source can employ the
delay of repair provisions. A source that neither repairs a
leak nor uses the delay of repair provisions is in violation..
Comment: One commenter (A-97-17; IV-G-07) stated that
§63.1027 (c) should use an equation in §65.108 (c) [from the
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proposed consolidated federal air rule (CAR)] to calculate the
connector leak rate. The commenter also suggested that the
EPA clarify that CL in §63.1027(c) should exclude those
connectors found leaking during the 90 day follow-up
monitoring. The commenter noted that such an exclusion-is
warranted to avoid double counting of leakers that could
result since the percent leak rate is calculated after all (or
a certain percentage of) connectors in the process unit have
been monitored.
Response: The EPA agrees with the commenter that
including connectors found leaking during the 90 day follow-up
monitoring in the %CL term of the percent leaking connector
calculation could lead to double counting of leaking
connectors. The EPA has revised the language in §63.1027(c),
as suggested by the commenter, in order to clarify that
connectors found leaking during the 90 day follow-up
monitoring are not included in the percent leaking connector
calculation.
6.9 PUMPS, VALVES, CONNECTORS, AND AGITATORS IN HEAVY LIQUID
SERVICE
Comment: One commenter (A-97-17; IV-G-07) recommended
changing the leak definition for heavy liquid pumps that are
not in polymerizing monomer or food/medical service from
1,000 ppm to 2,000 ppm. The commenter pointed out that,
although the leak definition for heavy liquid pumps is
1,000 ppm, they are not required to be repaired unless they
are detected to be leaking at or above 2,000 ppm. The
commenter also stated that a 2,000 ppm leak definition for
heavy liquid pumps would be consistent with the requirements
of 40 CFR part 63, subpart H (RON equipment leaks) .
Response: The EPA agrees with the commenter. For all
heavy liquid pumps that are not in polymerizing monomer
•service, EPA has previously held that an instrument reading of
2000 parts per million indicates a leak. The EPA has revised
the portions of §63.1029 (b) (2) relating to pumps in heavy
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liquid service to read: "If an instrument reading of ...
2,000 parts per million or greater for all other pumps
(including pumps in food/medical service) ... is measured, ...
a leak is detected...."
6.10 QUALITY IMPROVEMENT PROGRAM FOR PUMPS
Comment: One commenter (A-97-17; IV-G-07) requested
clarification on portions of the quality improvement program
(QIP) requirements for pumps in §63.1035. The commenter
interpreted that data analysis of pumps in the QIP, which
according to §63.1035 (d) (5) must be completed within 18 months
of beginning the QIP, is not required if the facility meets
the criteria to exit the QIP in less than 18 months. The
commenter requested that this point be clarified. The
commenter also requested clarification on whether a facility •;
subject to QIP requirements for the first time would be
required to comply with the requirements of the trial
evaluation in §63.1035(d)(6) if a data analysis has already
identified a superior pump design, technology or operating and
maintenance practice. Similarly, the commenter requested
clarification on whether a facility subject to QIP
requirements for the first time would be required to conduct
performance trials required in §63.1035 (d) (6) if a superior
performing pump seal or pump technology has already been
identified. The commenter also pointed out that the quality
assurance program in §63.1035(d)(7) and the pump replacement
program in §63.1035(d)(8) require that a facility implement
these programs after having been in the QIP for 3 or 4 years,
depending on the number of employees and number of pumps at
the facility. The commenter requested clarification on how to
determine the length of time a facility has been in the QIP
program if the facility has exited and reentered the QIP
program one or more times.
Response: In response to clarifying what to do for a
facility that exits a QIP in less than 18 months, EPA agrees
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with the commenter that the first data analysis would not be
required.
In response to the issue of facilities implementing a QIP
for the first time, EPA agrees that a trial evaluation program
would not be necessary if a data analysis specific to the
individual situation at the facility had previously been
conducted. This pre-existing data analysis would have already
identified the services, operating or maintenance practices,
and pump or pump seal design technologies with better than
average emission performance. The requirement under the QIP
would then be to begin implementation of the superior
technology through the replacement program.
In response to the question regarding the time period
requirements of the QIP, EPA notes that the 3 and 4 year
requirements would refer to the time passed since the first
triggering of the QIP. The EPA notes that the QIP was
developed for poorly performing facilities and was not
envisioned as an additional burden to facilities operating on
the edge of triggering a QIP. The EPA recognizes that, in the
absence of data identifying a superior technology, a facility
entering and exiting a QIP must re-enter the'QIP at the
performance trial step.
6.11 ENCLOSED VENTED PROCESS UNITS OR AFFECTED FACILITIES
Comment; One commenter (A-97-17; IV-G-07) recommended
that the enclosed-vented process unit provisions in §63.1037
be revised to allow for either a process unit or a portion of
a process unit to be designated as an enclosed-vented process.
The commenter also requested that enclosed-vented process
units be given the option to be routed to a fuel gas system or
to a process. In addition, the commenter suggested that
enclosed-vented process units should not be exempt from the
closed vent system and control device requirements of
§63.1034.
Response: The EPA notes that the enclosed-vented process
unit alternative is intended for process units entirely
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contained within large buildings, where all emissions will
vent through a limited number of exhaust ports. Many of these
process units are unmanned. Pharmaceutical processors are
typical examples of this type of operating scenario.
The EPA maintains that it is inappropriate to allow the
enclosed-vented alternative for portions of process units.
Doing so creates confusing compliance situations and stretches
the scope of the allowance beyond what was originally
intended.
6.12 REPORTING REQUIREMENTS
Comment: One commenter (A-97-17; IV-G-07) recommended
that the requirement to report nonrepairable components as
part of the periodic reporting requirements of §63.1039 (b) (1)
be removed. This paragraph requires the owner or operator to •
"include the number of leaking components that were not
repaired as required by §63.1024(a), and for valves and
connectors identify the number of components that are
determined by §63.1025 (c) (3) to be nonrepairable." The
commenter stated that this requirement is redundant with the
requirement in §63.1039 (b) (2) to report occurrences of delay
of repair. The commenter also stated that §63.1025(c)(3) is
referenced in the valve section, but there is no parallel
reference for nonrepairable connectors in the connector
section. The commenter requested clarification on reporting
the number of leaking components that were not repaired as
required hy §63 = 1024 (a) . The ccmmentcr inquired if the intent
was for the owner or operator to report the number of
components which missed either the 5 day first attempt and/or
the 15 day final repair for reasons other than delay of
repair.
Response: With regard to the apparent redundancy in
periodic reporting requirements, EPA notes that §63.1039 (b) (1)
requires reporting of the number of leaking components that
were not repaired. This number refers to the components not
repaired within the 15 day time period. It does not include
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the number of components that are not repaired pursuant to the
requirement to perform a first attempt at repair within 5
days.
In addition, this number may not be the same number as
the instances of delay of repair, which is required to be
reported under §63.1039(b)(2). For example, one component may
leak multiple times during a reporting period. This may
necessitate more than one instance of delay of repair, but the
number of components that leaked is still one.
With regard to reporting the number of nonrepairable
connectors, EPA recognizes that subpart UU does not provide
for designating connectors as nonrepairable. To correct this
oversight, EPA has revised §63.1039(b)(1) so that the section
does not refer to connectors.
6.13 OTHER COMMENTS
6.13.1 General Comments
Comment: One commenter (A-97-17, IV-G-07) suggested that
all references made to subpart SS in subpart UU should be
revised to refer instead to §63.1034, which governs closed vent
systems and control devices, or emissions routed to a fuel gas
system or process, so that no requirements are overlooked.
Response: The commenter is correct, and the final rule
has been revised to make this change. By referencing §63.1034,
the EPA ensures that the appropriate requirements for closed
vent systems and control devices, or emissions routed to a fuel
gas system or process are met by the owner or operator subject
to these provisions. Section 63.1034 itself cross-references
subpart SS, and this cross-reference has been maintained in the
final rule, as subpart SS holds the detailed requirements that
must be met.
Comment: One commenter (A-97-17, IV-G-07) stated that
references to the monitoring method requirements in each
equipment section are incorrect and inconsistent. In most of
these sections, the owner or operator is referred to the
monitoring requirements of §63.1023(b), (c), and (e), when in
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fact only (b) and (c) address monitoring methods, and paragraph
(e) is about identification and records. The commenter stated
that all of these references should be consistent, and should
either refer to §63.1023(b) or §63.1023(b) and (c).
Response: The commenter is correct about the need for
consistency and accuracy in cross-referencing monitoring method
requirements. Section 63.1023(b) addresses instrument
monitoring methods for leak detection and §63.1023 (c) addresses
instrument monitoring using background adjustments, which is
optional. Therefore, the EPA has revised the rule to refer to
the monitoring requirements of "§63.1023 (b) and, as applicable,
(c) ."
Comment: One commenter (A-97-17, IV-G-07) noted that
§63.1025(b) gives exceptions to monitoring requirements for
valves pursuant to §§63.1021(b), 63.1036, 63.1037, and
paragraph (e) of this section. However, the commenter stated,
all of the other equipment sections omitted some of these
exceptions, and therefore these need to be added to the
following sections: 63.1026(b), 63.1027(b), 63.1028(c),
63.1029(b), 63.1030(b), 63.1031(b), 63.1032(b), and 63.1033 (b) .
The commenter noted that for §63.1030 (b), the exception from -
§63.1021(b) is not appropriate, as §63.1030 is a performance
standard. This comment is similar to one received on analogous
provisions in subpart TT.
Response: The commenter is correct regarding the need for
consistent referencing of exemptions througi'iuuL Liie rule. Tne
commenter is also correct regarding the appropriate placement
of exemptions on the leak detection parts of the rule and delay
of repair conditions in the leak repair parts of the rule. The
EPA has revised the final rule accordingly, and the leak
detection parts of each section of the rule include the
exemptions provided under §63.1021 (b) (Alternative means of
emission limitation), §63.1036 (Alternative means of emission
limitation: Batch processes), §63.1037 (Alternative means of
emission limitation: Enclosed-vented process units), and within
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the respective sections of the rule (e.g. the special
provisions for pumps found in §63.1026 (e)) . Furthermore, the
references to delay of repair exceptions have been revised to
appear only in the leak repair parts of the sections in the
final rule, as these are not relevant to the leak detection
requirements found in the rule.
Comment: One commenter (A-97-17, IV-G-07) stated that
whenever subpart UU refers to routing emissions to a fuel gas
system or process, or to a closed vent system and control
device meeting the requirements of §63.1034 or subpart SS,
reference should also be made to the alternative means of
emission limitation provision of §63.1021 (b). The commenter
listed several sections which do include this, and several more
which do not, but should. For example, §63.1030(d) is cited as
an example of appropriate language.
Response: The commenter is correct that this language
should be consistent throughout the rule, and that each
reference to meeting the requirements of §63.1034 should also
reference the alternative means of emission limitation
provisions of §63.1021 (b) . The rule has been revised to include
this reference wherever appropriate, and the language in these
various paragraphs.now reads as follows: "...is routed to a
fuel gas system or process or equipped with a closed vent
system....meeting the requirements of either §63.1034 or
§63.1021(b)..."
6.13.2 Applicability
Comment: One commenter (A-97-17, IV-G-07) stated that
surge control vessels and bottoms receivers should be deleted
from the list of equipment in §63.1019 (b) to which subpart UU
is applicable, since there are no standards within subpart UU
pertaining to them. Likewise, the reference to surge control
vessels and bottoms receivers in the equipment definition of
§63.20 should be deleted.
Response: The EPA has deleted the definition of
"equipment" from the final rule. Subpart UU of 40 CFR part 63
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was not meant to specify the applicability. The referencing
subpart (to subpart UU) is required to specify the
applicability which then directs an owner or operator of a
subject source to subpart UU.
6.13.3 Definitions
Comment: One commenter (A-97-17, IV-G-07) stated that the
definitions for "first attempt at repair" and "repaired" need
to include a reference to §63.1023 (c) for those owner or
operators who choose to monitor using background adjustments.
Furthermore, the commenter asserted that when referring to
§63.1023(b) or (c), "as appropriate" should be added, since
visual leakers may not require remonitoring [as in
§63.1026(b)(5)].
Response: The EPA notes that "visual leakers" requirements
typically include language to the effect of "repaired in this
instance means that the visual indications of a leak have been
eliminated." Therefore, the standard definition of "repaired"
would not apply, and adding the phrase "as appropriate" to the
definition of "repaired" is confusing and is not necessary.
The EPA maintains that it is not appropriate to add the
suggested language to §§63.1023 (b) and (c) .
Also, EPA notes that §§63.1023 (b) and (c) require follow-
up monitoring after a leaking valve has been repaired. The
requirement is equally applicable whether "repair" was
successful on the first, second, third, or any subsequent
attempt at repair, if the required "first attempt at repair"
is successful (and proven through monitoring to be "repaired"),
then follow-up monitoring is required within 3 weeks.
Comment: One commenter (A-97-17; IV-G-07) wondered why
there was no explanation in the preamble as to why both of the
terms "relief device or valve" and "pressure relief device or
valve" are needed. The commenter believes that, consistent
with the CAR, "relief device or valve" is intended to include
relief valves that do not relieve pressure, and stated that if
this is the case, the definition of relief device or valve
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should mention those relief valves that let in nitrogen to
prevent vacuums.
Response: The definition for "pressure relief device or
valve" contained in Subpart UU specifically notes that "devices
activated... by a vacuum are not pressure relief devices." A
"relief device or valve" in Subpart UU means a "device or valve
used only to release an unplanned, non-routine discharge, " not
necessarily relieving pressure. Pressure relief devices are a
subset of relief devices.
The change noted by the commenter is regarding the
definition of "open-ended valve or line." The intent of this
term is that relief devices, the broader category of devices
needed for safety purposes or equipment protection, are not
considered open-ended valves. The language used in Subpart UU,
therefore, specifically exempts "relief valves" in the
definition of "open-ended valve or line" instead of exempting
"pressure relief valves," as was done in the RON and 40 CFR
part 61, subpart V. (The EPA notes that no change is being
proposed to the RON definition of "pressure relief device or
valve."
Comment: One commenter (A-97-17; IV-G-07) stated that the
definition of "set pressure" needs to remove the reference to
subparts F and G, since these reference the CAR, not subpart
UU.
Response: The commenter is correct that these cross-
references should not remain in the definition of set pressure,
and the EPA has revised the final rule accordingly.
6.13.4 Equipment Identification
Comment: One commenter (A-97-17; IV-G-07) stated that the
reference in §63.1022 (b) (1) to the initial survey required by
§63.1027 (a) (1) or paragraph (a) (of §63.1022) is incorrect, and
that the reference to paragraph (a) should be removed as it
does not make sense, and the reference to §63.1027(a)(1) should
be changed to §63.1027(a) since there is no (a) (1) .
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• Response: The commenter is only partially correct. While
there is no §63.1027 (a) (1), §63.1027(a) does not require an
initial survey, and this is the reference that should be
deleted from the cited sentence. The final rule has been
modified to read as follows: "With respect to connectors, the
identification shall be complete no later than the completion
of the initial survey required by paragraph (a) of this
section."
Comment: One commenter (A-97-17; IV-G-07) stated that the
reference in §63.1022 (b) (5) should specifically reference
"§63.1029" instead of "the provisions of this subpart."
Response: Since the paragraph in question refers to
equipment in service less than 300 hours per calendar year, and
§63.1029 is entitled "Pumps, valves, connectors, and agitators-
in heavy liquid service; pressure relief devices in liquid
service; and instrumentation systems standards," the EPA does .
not believe that further clarification is needed.
6.13.5 Instrument and Sensory Monitoring for Leaks
Comment: One commenter (A-97-17; IV-G-07) stated that
language in subpart .YY explaining what to do if the initial
compliance date occurs after the beginning of a standard
calendar period should be added to §63.1023 of subpart UU.
Response: The EPA does not agree with the commenter's
recommendation that provisions addressing the circumstances
when the initial compliance date occurs after the beginning of
a standard calendar period should be included in subpart UU.
Instead, the EPA believes that it is appropriate to address
this issue in the referencing subpart, which is why this
language is included in subpart YY. Furthermore, there is no
need for this information to appear in more than one location.
The referencing subpart will establish initial compliance dates
for the sources it regulates, and thus it is appropriate that
issues regarding this initial compliance date would also be
addressed in the referencing subpart. The EPA has made no rule
change in response to this comment.
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Comment: One commenter (A-97-17; IV-G-07) stated that
while §63.1023(a)(1) lists cases for which instrument
monitoring for leaks is required, monitoring required by other
sections should also be included in this paragraph. The
commenter specifically stated that the monitoring required by
§§63.1025(d) (2), 63.1026(b) (4) (i), 63.1026(e) (1) (v) (A),
63.1027(b) (3) (iv), 63 .1028 (c) (3) (ii) (A), 63.1028 (e) (1) (iv) (A) ,
63.1029(b), 63.1036(c), and also monitoring required after the
first attempt at repair and final repair (according"to the
definitions) should all be included in §63.1023(a)(1).
Response: The EPA disagrees with the commenter regarding
the need to list these cross references individually. Because
of the high number of cases where monitoring would be required,
the addition of these examples to §63.1023 (a) (1) would not
clarify the intent of the requirements.
Comment: One commenter (A-97-17; IV-G-07) stated that the
requirement in §63.1036(b)(6)(iii) for sensory monitoring
should be included in the list of sensory monitoring for leaks
requirements in §63.1023(a) (2) .
Response: The EPA disagrees with the commenter's suggested
modification. There is no clarification benefit associated
with providing such a cross reference. .
Comment: One commenter (A-97-17; IV-G-07) stated that
§63.1023(a)(2)(ii) requires that "...inaccessible, ceramic, or
ceramic-lined connectors...be observed pursuant to
§63.1027(e) (2) ." However, §63.1027 (e) (2) does not require
observation; it only requires that if a connector is found
leaking, it must be repaired. Therefore, the commenter
asserted, §63.1023 (a) (2) (ii) should be deleted. The same
commenter noted that §63.1023(a)(2)(iv) requires monitoring for
pumps, valves, agitators and connectors in heavy liquid
service; instrumentation systems; and pressure relief devices
in liquid service, "pursuant to §63.1029 (b) (1)," but that
§63.1029 (b) (1) does not in fact require observation. Instead
it requires monitoring within 5 days if a potential leak is
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found. Again, the commenter recommended that the paragraph be
deleted.
Response: The commenter is correct regarding inspection
requirements for inaccessible, ceramic, or ceramic-lined
connectors and for pumps, valves, agitators and connectors in
heavy liquid service; instrumentation systems; and pressure
relief devices in liquid service. Thus, the EPA has deleted
the provisions of §6.3.1023(a) (2) (ii) and §63.1023(a) (2) (iv)
from the final rule, and reserved the paragraphs.
Comment: One commenter (A-97-17; IV-G-07) stated that
water is usually given as an example of an inert, and the
commenter recommends adding it to the phrase found in
§63.1023(b)(2): "For process streams that contain nitrogen,
air, or other inerts that are not organic HAP." ;
Response: The commenter's requested change has been made
in the final rule, and water is included in §63.1004 (b) (2) as
an example of an inert that is not an organic HAP. This does
not change the intent of the regulation, but the EPA believes
that if this revision is helpful to the owner or operator, then
it is beneficial and appropriate.
Comment: The commenter (A-97-17, IV-D-02) states that
language in §§63.1023(c)(3) governing monitoring should read'
"within one centimeter" rather than "as close to the interface
as possible" for monitoring of moving components such as pumps
and compressors.
Response: The EPA has revised this paragraph in .the find!
rule to remove the phrase "as close to the interface as
possible." Instead, this paragraph will refer simply to Method
21 of 40 CFR part 60, appendix A, for requirements on how
monitoring should be conducted.
Comment: Section 63.1023 (e) (2) requires that when a leak
is detected, the information in paragraphs (e)(2)(i) and (ii)
be recorded and kept. The commenter (A-97-17; IV-G-07) stated
that paragraphs (e)(2)(i) and (ii) should be deleted, and the
reference should instead be to §63.1024 (f), Leak repair
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records, because this consists of a more complete list of the
information that needs to be recorded and retained.
-Response: The commenter is correct. The list of
information required to be kept under §§63.1023(e)(2)(i) and
(e)(2)(ii) when a leak is detected is a subset of the
information listed in §63.1024 (f), Leak repair records. The EPA
has revised the rule by deleting §§63.1023 (e) (2) (i) and
(e)(2)(ii), and cross-referencing the provisions of
§63.1024(f).
6.13.6 Leak Repair
Comment: Section 63.1024(d)(3)(ii) requires that purged
material be collected and destroyed or recovered in a control
device complying with subpart SS after repair. The commenter
(A-97-17; IV-G-07) stated that the option of routing the purged
material to a process or fuel gas system should be added. The
commenter also asserted that the reference to subpart SS should
be changed to §§63.1034 or 63.1021(b).
Response: The commenter's assertion that
§63.1024(d) (3) (ii) should allow for the option of routing
purged material to a fuel gas system or process is a valid one,
and the EPA has added this option to the final rule. Also, in
accordance with changes made throughout the rule to refer to
§63.1015 (Closed vent systems and control devices; or emissions
routed to a fuel gas system or process standards) instead of to
subpart SS, it is also appropriate that this provision require
compliance with the requirements of §63.1034 or §63.1021(b),
Alternative means of emission limitation.
Comment: One commenter (A-97-17; IV-G-07) stated that the
reference in §63.1024 to paragraphs (e)(1) and (e)(2) of this
section for the description of unsafe-to-repair should be
deleted, since this paragraph already refers to §63.1022(d),
and the information in (e)(1) and (e)(2) is the same as that in
§63.1022(d). The commenter further recommended that paragraphs
(e)(1) and (e)(2) be deleted.
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Response: Section §63.1024 (e) addresses unsafe-to-repair
connectors "as described in §63.1022(d)," and then
subparagraphs (e)(1) and (e)(2) restate the criteria listed in
§63.1022(d) for designation as unsafe-to-repair. The commenter
is correct that §§63.1024 (e) (1) and (e) (2) are redundant with
the provisions of §63.1022 (d), and the EPA has deleted these
paragraphs from the final version of the rule.
6.13.7 Valves in Gas and Vapor Service and in Light Liquid
Service Standards
Comment: Section 63.1025 (b) (4) (v) requires the owner or
operator to notify the Administrator of the decision to begin
or end subgrouping of valves no less than 30 days before the
beginning of the next monitoring period, and states that this
notification can be included in the next periodic report. The -"
commenter (A-97-17; IV-G-07) requested clarification regarding
whether the option to include the notification in the next
periodic report applies regardless of when the beginning of the
next monitoring period occurs.
Response: The notification to begin or end subgrouping of
valves must be submitted at least 30 days prior to the
beginning of the monitoring period in which the change is made.
This notification can be included with a periodic report if
this will be submitted at least 30 days before the beginning of
the next monitoring period; in this case, a separate
notification is not required. The EPA also notes that only a
single not ice of the decision tc begin or end subgrouping is
required.
Comment: The commenter (A-97-17, IV-G-07) stated that the
VL term in the percent leaking valves calculation in
§63.1025 (c) (1) (ii) should include valves found leaking pursuant
to §63.1025(d) (2) (iii) (A) and (B), as applicable. The commenter
believed that otherwise, the owner or operator may overlook the
requirement to consider valves found leaking during follow up
monitoring.
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Response: The EPA agrees with the commenter and has
revised §63.1025 (c) (1) (ii) accordingly.
Comment: Section 63.1025(d)(2) requires that a valve be
monitored at least once in the first 3 months after its repair,
and states that the monitoring required is in addition to the
monitoring required to satisfy the definition of "repaired."
The commenter (A-97-17; IV-G-07) believed that this statement
should also reference the definition of "first attempt at
repair" since monitoring is also required after this.
Response: The EPA notes that subpart UU requires follow-up
monitoring after a leaking valve has been repaired. The
requirement is equally applicable whether "repair was
successful on the first, second, third, or any subsequent
attempt at repair. If the required "first attempt at repair"
is successful (and proven through monitoring to be "repaired"),
then follow-up monitoring is required within 3 months.
Comment: Section 63 .1025 (e) (3) establishes requirements
when there are fewer than 250 valves. The commenter (A-97-17;
IV-G-07) pointed out that the cross-reference to (b)(4)(iii),
(iv), or (v) doesn't make sense as an alternative to quarterly
monitoring, as those paragraphs address valve subgrouping. The
commenter believed that the cross-reference is a carryover from
subpart TT, but that there is no equivalent for UU, and the
reference should be deleted.
Response: The EPA acknowledges that the provisions for
plant sites with fewer than 250 valves contained an incorrect
reference at proposal. The EPA has edited the section to
specify that at plant sites with fewer than 250 valves,
monitoring will be required quarterly or at a frequency
specified through the optional subgrouping procedure.
6.13.8 Pumps in Light Liquid Service Standards
Comment: One commenter (A-97-17; IV-G-07) stated that
§63.1026 (e) (1) (viii), which states, "When a leak is detected
pursuant to paragraph (e)(1)(vi) of this section...", should
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refer to (e)(1)(v) as well as (e)(1)(vi), as there is otherwise
no repair time limit.
Response: The EPA has modified the cross reference in
§63.1026(e)(1)(viii) to refer to §63.1024.
Comment: One commenter (A-97-17; IV-G-07) stated that the
exemption in §63.1026 (e) (2) and (e) (3) from the "monitoring
requirements of paragraph (b)" for pumps with no external shaft
or pumps routed to a process or fuel gas system or equipped
with a closed vent system to a control device, is incomplete.
The commenter stated that such pumps should also be exempt from
the weekly visual inspection requirements of paragraph (b), and
the paragraph should be revised to state "...exempt from the
requirements of paragraph (b) of this section." The commenter
said that this would be consistent with the RON subpart H, NSPS-
subpart W and NESHAP subpart V.
Response: The commenter is correct and the EPA has
revised the rule to indicate that pumps with no external
shafts, or pumps routed to a process or fuel gas system or
equipped with a closed vent system to a control device, are
exempt from all of the requirements of §63.1026 (b).
Comment: One commenter (A-97-17; IV-G-07) stated that
unsafe-to-monitor pumps should be exempt from paragraphs (b)
through (d) of this section, not just (b) as stated in
§63.1026(e) (6). The commenter also recommended that the
exemption from "the repair requirements of §63.1024" be
radicts the requiternenL wiLhiii the
written plan of §63.1022 (c) (4), which is also referenced.
Response: In response to this comment, the EPA revised
§63.1026 (e) (6) of the final rule to read as follows:
"Any pump that is designated, as described in
§63.1022 (c) (1) (ii), as an unsafe-to-monitor pump is exempt
from the requirements of paragraph (b) of this section and
the requirements of §63.1024 and the owner or operator
shall monitor the pump according to the written plan
specified in §63.1022 (c) (4)"
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6.13.9 Connectors in Gas and Vapor Service and in Light
Liquid Service Standards
Comment: One commenter (A-97-17; IV-G-07) wondered
whether unsafe-to-monitor connectors should be exempt from the
initial monitoring requirements in paragraph (a) as well as
those in (b) (1) through (b) (3) as specified in §63.1027 (e) (1) .
The commenter asked, "what if the connector is not safe to
monitor for the whole first 12 months?"
Response: The EPA agrees with the commenter and has
modified §63.1027 (e) (1) to exempt uns'afe-to-monitor connectors
from the requirements of §§63.1027(a) and (b).
Comment: One commenter (A-97-17; IV-G-07) stated that the
provision in §63.1027(e)(2)(i) should exempt inaccessible,
ceramic, or ceramic-lined connectors from leak repair
provisions in paragraph (d). as well as the provisions of (a)
and (b), since §63.1027(e)(2)(ii) specifies a leak repair
requirement for these connectors.
Response: The EPA agrees with the commenter and has
exempted inaccessible, ceramic, or ceramic-lined connectors
from the leak repair requirements in section §63.1027.
6.13.10 Agitators in Gas and Vapor Service and in Light
Liquid Service Standards
Comment: One commenter (A-97-17; IV-G-07) stated that the
reference in §63.1028 (c) (3). (ii) (A) to the repair requirements
of §63.1024 should be deleted because it is redundant with
paragraph (d), the leak repair section.
Response: The EPA agrees with the commenter and has
removed the cross reference to §63.1024; the final rule does
reference the leak repair requirements in §63.1028(d).
6.13.11 Pumps. Valves, Connectors, and Agitators in Heavy
Liquid Service; Pressure Relief Devices in Liquid
Service; and Instrumentation Systems Standards
Comment: One commenter (A-97-17; IV-G-07) stated that the
phrase "5,000 parts per million or greater for pumps handling
agitators" in §63.1029(b)(2) should be deleted, because 5,000
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ppm applies to pumps handling polymerizing monomers, and 10,000
ppm applies to agitators.
Response : The commenter is correct, and the final rule
has been revised accordingly.
6.13.12 Sampling Connection Systems Standards
Comment: One commenter (A-97-17, IV-G-07) stated that
§63. 1032 (c) should be amended to specify that the fuel gas
system or process in (c) (1) be in compliance with the
requirements of §§63.1034 or 63. 1021 (b) . The commenter also
stated that paragraph (c) (2) should be deleted as it is a
subset of paragraph (c) (1) .
Response : The commenter is correct on both counts.
Paragraph (c) (1) and (c) (2) both require purged process fluid
to be collected and returned to a fuel gas system or process, ,
though the requirement is worded differently in each paragraph.
Therefore, the EPA deleted and reserved paragraph (c) (2) , as •
its .intent is addressed by paragraph (c) (1) . Furthermore, to
be consistent with other changes made to the rule,
§63. 1032 (c) (1) was revised to specify that a fuel gas system or
process to which purged process fluid is returned must be in
compliance with §63.1034 or §63. 1021 (b).
6.13.13 Closed Vent Systems and Control Devices; or Emissions
Routed to a Fuel Gas System or Process Systems
Comment: The commenter (A-97-17; IV-G-07) stated that
§63. 1034 (b) is incomplete, because it does not specify an
referencing subpart. The commenter further noted that the
special case for enclosed combustion devices is missing. The
commenter proposed rewriting this paragraph (similar to
§63. 172 (a) through (c) of the HON, subpart H) , as follows:
" (b) Compliance standard. (1) Owners or operators
routing emissions from equipment leaks to a fuel gas
system or process shall comply with the provisions of
subpart SS of this part, except as provided in
§63.1021 (b) .
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(2) Owners and operators of closed vent systems and
control devices used to comply with provisions of
this subpart shall comply with the provisions of
subpart SS of this part and (b)(2)(i) through
(b)(2)(iii), except as provided in §63.1021(b).
(i) Nonflare control devices shall be designed and
operated to reduce emissions of regulated material
vented to them with an efficiency of 95 percent or
greater, or to an exit concentration of 20 parts per
million by volume, whichever is less stringent. The
20 parts per million by volume performance standard
is not applicable to the provisions of §63.1037.
(ii) Enclosed combustion devices shall be designed
and operated to reduce emissions of regulated
material vented to them with an efficiency of 95
percent or greater, or to an exit concentration of 20
parts per million by.volume, on a dry basis,
corrected to 3 percent oxygen, whichever is less
stringent, or to proved a minimum residence time of
0.50 seconds at a minimum temperature of 760°C.
(iii) Flares used to comply with this subpart shall
comply with the reguirements of subpart SS of this
part." Similar comment received on subpart TT.
Response; After careful review of the proposed rule,
analogous provisions in the RON, and the commenter's suggested
revisions to the rule, the EPA decided to adopt the commenter's
suggested language and organization for this paragraph. As
proposed, the requirements itemized in §63.1034 of the rule did
not completely and clearly establish.the provisions for
enclosed combustion devices. The requirements of this section,
as revised in the final rule, are clearer, more complete, and
easier to follow. These changes, while not altering the intent
or the requirements of the rule, increase the clarity of its
provisions, thereby facilitating compliance by owners and
operators.
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6.13.14 Quality Improvement Program for Pumps
Comment: The commenter (A-97-17; IV-G-07) stated that
§63.1035 (c) should be revised to clarify the criterion for
resumption of the QIP. The commenter's suggested revision is
shown below:
"the process unit has the greater of either 10
percent of the pumps leaking or three pumps
leaking..."
Response: The commenter is correct that this language
needs revising for clarity. The EPA has revised the language
in this paragraph to refer to "greater than either 10 percent
of the pumps leaking or three pumps leaking..."
6.13.15 Alternative Means of Emission Limitation: Batch
Processes
Comment: One commenter (A-97-17; IV-G-07) was confused
about the pressure test provisions of §63.1036(b). Sections
63.1036 (b) (4) (ii) and 63.1036(b) (7) (v) refer to "two
consecutive pressure tests," but the commenter inquired where
§63.1036 allows two consecutive pressure tests. If the first
test indicates a leak, the commenter noted, the owner or
operator must repair and retest. Is the retest the second
consecutive pressure test? Furthermore, the commenter noted
that if you fail the retest, you have 30 days after the second
pressure test to repair the leak, and asks whether this means
30 days after the test?
requirements in this §63.1036 (b) is as follows: The retest is
the second of two consecutive pressure tests. The "or" in the
rule has been replaced by parenthesis to help make the issue
clearer. The rule now reads, "...if a batch product process
fails the retest (the second of two consecutive pressure
tests)...."
The EPA believes that this action should clarify that an
owner or operator has 30 days after failing the retest to
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repair the leak. This is the same as specifying 30 days after
failing the second of two consecutive pressure tests.
Comment: One commenter (A-97-17; IV-G-07) stated that
§63.1036(b)(5)(iv) requires that if necessary, the test must be
extended "for the time necessary to detect a pressure loss or
rise that equals a rate of 1 [psig] per hour..." The commenter
wondered whether this means that the test must continue
indefinitely if the required pressure loss or rise is not seen?
Response: To clarify how long the test would need to be
extended, consider the following example. A process operating
at 200 pounds per square inch gauge (psig) is -tested, and the
owner or operator elects to use a pressure measurement device
with a precision of 20 psig (±10 percent of the test
pressure). Such a device would not be able to detect a
pressure drop of 1 psig/hour in 1 hour because it could only
detect a change of ±20 psig. The test must be extended to 20
hours. After 20 hours, if the process is losing pressure at a
rate greater than 1 psig/hour, then the instrument would be
able to detect this change because the change would be greater
than the precision of the device (±20 psig).
6.13.16 Recordkeeping Requirements
Comment: One commenter (A-97-17; IV-G-07) stated that the
cross-reference in §63.1038(c)(1)(i) to the monitoring schedule
for valves should be changed to §63.1025(b)(3)(vi) from
§63.1025(b) (3) (i) .
Response: The commenter is correct. Paragraph (b)(3)(vi)
contains the recordkeeping requirement for the monitoring
schedule, and the final rule has been revised accordingly.
Comment: One commenter (A-97-17; IV-G-07) stated that the
cross-reference in §63.1038(c)(3) to the monitoring schedule in
§63.1027(b) (3) is erroneous because there is no such schedule
in that paragraph. The commenter asserted that the correct
reference is §63.1027 (b) (3) (v) .
Response: The commenter is correct, and the rule has been
revised accordingly.
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Comment: One commenter (A-97-17; IV-G-07) contended that
visual inspection records required by §§63.1028 (b) (3)and
(e) (1) (iv) should be included in the recordkeeping requirement
of §63.1038(c)(4).
Response: The commenter is correct that clarification is
needed to the visual inspection recordkeeping requirements in
§63.1038(c)(4). The EPA has revised the final regulation to
reflect visual inspections as specified in §63.1028.
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7.0 NATIONAL EMISSION STANDARDS FOR STORAGE VESSELS (TANKS) -
CONTROL LEVEL 2 (40 CFR PART 63, SUBPART WW)
7.1 GENERAL COMMENTS
Comment: Two commenters (A-97-17, IV-D-02; A-97-17, IV-G-
02) stated that subpart WW should address startup, shutdown,
and malfunction events.
Response: The commenter did not provide examples of
situations where startup, shutdown, and malfunction provisions
may be needed. The EPA is unaware of situations where such
provisions are needed that are specific to Subpart WW. Subpart
YY references subpart WW for control of storage vessel
emissions. Subpart YY contains general startup, shutdown, and
malfunction provisions. Therefore, 'any vessel subject to
subpart WW would also be subject to subpart YY, and so the
provisions of subpart YY would apply.
Comment: One commenter (A-97-17, IV-G-05) stated that the
"standard standard" and generic MACT approaches will be
beneficial to setting reasonable and cost-effective control
standards.
Response: The EPA agrees.
7.2 APPLICABILITY
Comment: Two commenters (A-97-17, IV-D-02; A-97-17, IV-G-
02) stated that "physical process change" used in §63.1060(b)
should be defined or explained in the regulation.
Response: The EPA has removed the paragraph in question
from the final rule because it served only as an explicit
reminder that the control requirements of subpart WW do not
apply if a tank no longer satisfies the applicability criteria
of the subpart which references subpart WW.
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Comment: One commenter (A-97-17, IV-D-02) requested
clarification on whether flares and recovery devices were
acceptable control devices to which an enclosure may be vented
under §§63.1062 (a) (8) and 63.1065.
Response: Flares and recovery devices which meet
specified requirements are acceptable control devices for
storage vessels. In the final subpart YY, all possible control
options are not listed. The owner or operator is referred to
subparts SS and WW (floating roofs). Subpart SS lists options
for storage vessels and their associated requirements.
7.3 DEFINITIONS
Comment: Two commenters (A-97-17, IV-D-02; A-97-17, IV-G-
05) noted that "safety device" is not defined in Subpart WW.
(The commenter noted that this term is defined in Subpart DD ;
(Off Site Waste and Recovery Operations NESHAP). One commenter
(A-97-17, IV-G-05) suggested referring to Tank Level 1 control
definitions of 40 CFR 63.901.
Response: The EPA has decided to remove these provisions^
from the final rule. They were included in the proposed
subpart WW not for the source categories that were proposed
with it (in subpart YY), but for future source categories that
may need such provisions. The EPA has decided to add such
provisions in the future if they are needed.
Comment: One commenter (A-97-17, IV-G-02) stated that the
definition for "capacity" should be deleted because it is not
nqpH or needed in this regulation. Another cciriiricntsr (A~~97 17
IV-D-02) stated that "capacity" should not refer to the tank's
"external shell height" but rather should incorporate "its
design liquid level" (per American Petroleum Institute (API)
Standard 650). The commenter stated that the design liquid
level is "the highest level to which the tank may be filled,
which is the internal height of the tank shell unless
restricted by overflow slots or by fixed roof obstructions and
the profile of the floating roof."
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Response: The term "capacity" is used in Subpart WW. In
the proposed subpart WW, the definition of capacity stated that
it is based on the external shell height. It should have
stated that capacity is based on the internal shell height, as
is stated in the proposed subpart YY. Existing rules use the .
term "capacity" but do not define it, which has led to
questions on the determination of capacity. In response to
those questions, the EPA has stated that capacity is the
internal cross-sectional area of a tank multiplied by the
internal height of the tank shell, and that operational
restrictions such as design liquid levels and overflow valve
heights shall not be a consideration in determining internal
height. The final subpart WW contains a definition of capacity
which reflects the EPA's previous determination.
Comment: One commenter (A-97-17, IV-D-02) stated that the
definitions for "deck cover," "empty or emptying," "fill or
filling," and "initial fill or initial filling" be deleted and
any control or operational requirements implied by them should
be specified in the design requirements.
Response: The definition of deck cover in the final rule
has been revised to exclude the phrase which describes the
cover gasket. This requirement was moved to the section of the
rule containing design requirements. The other terms remain in
the final rule, and have been slightly modified.
Comment: One commenter (A-97-17, IV-D-02) suggested
modifications to definitions "pole float," "pole sleeve," "pole
wiper," and "slotted -guidepole" t© address concerns over
guidepoles and guidepole controls.
Response: The EPA agrees with the commenter, and the
definitions for these terms have been revised in the final
rule.
Comment: One commenter (A-97-17, IV-D-02) suggested
redefining "regulated material" to include "properties or
characteristics that exceed the cutoffs for control
requirements in the regulating subpart."
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Response: The term "regulated material" has been removed
from the final subpart WW, and has been replaced with the word
"liquid" in most instances. Owner and operators are referred
to subpart WW (by subpart YY) for control of emissions from
storage vessels that store liquids with vapor pressures that
exceed the applicability cutoffs in subpart YY. Therefore, an
owner or operator would be referred to subpart WW only when a
stored liquid is subject to regulation.
Comment: One commenter (A-97-17, IV-G-05) stated that
definitions for "pressurized storage vessel," "closure device,"
and "closed system" need to be added to §63.1061. The
commenter stated that the EPA should not refer to rules that
are unrelated to the generic MACT standard or the standards
proposed under the generic MACT approach.
Response: The EPA has decided to remove from the final •
rule the provisions in which the terms are used. The
provisions were included in the proposed subpart WW not for the
source categories that were proposed with it (in subpart YY), .
but for future source categories that may need such provisions.
The EPA has decided to add such provisions in the future if
they are needed.
7.4 STORAGE VESSEL CONTROL REQUIREMENTS
Comment: Two commenters (A-97-17, IV-D-02; A-97-17, IV-G-
04) stated that the Subpart SS references that are found in
Subpart WW [one commenter noted §63.1062 (a) (3) and (a) (4);
another commenter noted §63.1163] should net contain auditioiidl
requirements for flares and control devices.
Response: The EPA agrees. The final subpart WW is only
for floating roofs, and subpart SS includes all the
requirements for closed vent systems and control devices that
may be used for the control of storage vessel emissions.
Comment: The commenter also noted that §63.1062 only has
requirements at the paragraph (a) level and recommended the
addition of paragraph (b) as "reserved."
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Response: • The EPA has made the commenter's recommended
change.
7.5 FLOATING ROOF REQUIREMENTS
Comment: One commenter (A-97-17, IV-D-02) suggested that
the final rule clearly address seams in rim seal materials.
The commenter supplied recommended text for §63.1063(a) (1)
concerning rim seal seams.
Response: Most questions about rim seals in existing
rules have resulted from the use of the term "continuous" when
describing seals. The term has been used to convey that a seal
must cover the entire annular space between the rim of the
floating roof and the tank shell (except for gaps smaller than
those specified in the rule). The term does not require that a
rim seal must consist of only one piece. The proposed and
final subpart WW do not use the term "continuous" when
describing seals. The definition of mechanical shoe seal in
the final subpart WW states that the band that contacts the
tank shell may consist of a series of sheets (shoes) that are
overlapped or joined together to form a ring.
Comment: One commenter (A-97-17, IV-D-02) stated that
"emptied and degassed" should be replaced with "taken out of
service and degassed" in §63.1063 (a) (1) (i) (D), (ii) (C), and
(2)(ix). Two commenters (A-97-17, IV-D-02; A-97-17, IV-G-02)
stated that §63.1063(c)(1)(i)(B), (1)(ii)(B), and (2)(iii)
should include the phrase "taken out of service and degassed"
rather than "emptied and degassed."
Response: The final rule uses the phrase "completely
emptied and degassed" to describe when certain requirements
must be satisfied. The EPA believes that this phrase is
understandable. The phrase "taken out of service" is also
understandable, but would require a definition that would
include reference to the complete emptying of a storage vessel.
Comment: One commenter (A-97-17, IV-D-02) noted that
§63.1063(a)(2)(ix) should address requirements listed in
paragraphs (a)(2)(i) through (a)(2)(viii).
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Response: The EPA agrees with the commenter and has
amended §63.1063 (a) (2) (ix) of the final rule to address
requirements listed in paragraphs (a)(2)(i) through
(a) (2) (viii) .
Comment: One commenter (A-97-17, IV-D-02) suggested that
the deck fitting requirements in §63.1063 (a) (2) for internal
and external floating roof tanks should be separated so that
they are consistent with the requirements for the rim seal.
The commenter stated that controls for deck drains should only
apply to external floating roof tanks. The commenter supplied
suggested language for §63.1063(a)(2).
Response: The rim seal requirements are separate because
the type of rim seal system allowed depends on whether a tank
is an internal or external floating roof tank. For example, an
internal floating roof tank may have a single liquid-mounted
seal, but an external floating roof tank must have double
seals. For deck fittings, the control requirements do not
differ based on tank type. Of course, external floating roof
tanks have some fittings that most internal floating roof tanks
do not (e.g., rim space vents), and vice-versa. In these
cases the fitting requirements simply would not apply if a ;.,
particular tank did not have the fitting.
Comment: One commenter (A-97-17, IV-D-02) suggested
clarifications to the deck fitting control requirements in
§63.1063 (a) (2) (ii) through (v) . The commenter also stated that
gasketed deck fitting covers should be clearly specified in
these sections.
Response: The fitting control requirements in the final
rule have been clarified, and the requirement of gasketed deck
covers has been included in §63.1063, instead of defining deck
covers to include gaskets.
Comment: One commenter (A-97-17, IV-D-02) recommended that
the requirement to bolt covers for gauge float (automatic
gauge) openings be deleted from §63.1063 (a) (2) (vi) . The
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commenter stated that such requirements could cause gauging
errors or damage to the floating roof.
Response: The commenter did not provide actual cases of
damage caused by bolted covers on openings for gauge floats,
and the EPA has no information indicating that such damage has
occurred with existing bolted covers. The API has developed an
emission factor for gauge float openings with gasketed, bolted
covers, and the factor is significantly lower than the factor
for a cover with only a gasket. The requirement of a gasketed,
bolted cover appears in existing rules, and remains in the
final subpart WW.
Comment: One commenter (A-97-17, IV-D-02) stated that
flexible fabric sleeve seals should not be included as options
for guidepoles because such seals are control devices specific
to fixed roof support columns constructed of round pipe. The
commenter suggested that a pole sleeve be specified as an
option to a pole wiper for unslotted guidepoles. The commenter
also recommended that §63.1063(a)(2)(vii), (viii), and (ix)
specify that the height of the float for slotted guidepoles,
when used without a pole sleeve, be specified - the commenter
noted that the height should be specified in these sections
rather than in the definitions for this subpart.
Response: The EPA agrees with the comment on the flexible
fabric sleeve seal, and the final rule does not include such a
seal as an option for guidepoles. Information contained in
API's Manual of Petroleum Measurement Standards (Chapter 19,
Section 2) indicates that a pole wiper has a lower emission
factor than a pole sleeve at most wind speeds. The pole sleeve
is an option for slotted guidepoles, but a pole wiper is
required in addition to the sleeve. Since pole sleeves are
more commonly used for slotted guidepoles, the EPA believes
that pole sleeves would be supplied with pole wipers, even when
used for unslotted guidepoles. The final rule does not include
pole sleeves as an option for unslotted guidepoles. The EPA
agrees that the specification of the pole float wiper height
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should appear in the section containing the fitting
requirements, not in the definitions section, and the final
rule reflects this.
Comment: One commenter (A-97-17, IV-G-05) stated that
continuous emptying of a vessel if fluctuations lower the
liquid level below the leg level [per §63.1063(b)] is not
appropriate. The commenter stated that the increased vapor
space would increase emissions from continuous emptying. The
commenter noted that the proposed consolidated air rule for
SOCMI sources contains modifications to this emptying
requirement in the proposal preamble. The commenter suggested
that the EPA maintain consistency with §65.47(e) of the
consolidated air rule.
Response: The provision in the proposed rule basically
stated that when a floating roof rests on its legs, the tank
must be filled or completely emptied as soon as practical. The
language regarding emptying was included to make clear that an
owner or operator is allowed to remove liquid from a vessel
when its floating roof is resting on its legs. The EPA has
decided to remove this language in the final rule because
owners and operators are likely aware that the provision does .
not prohibit emptying in such cases.
Comment: Two commenters (A-97-17, IV-G-02; A-97-17, IV-
D-02) suggested that §63.1063(b) (2) regarding what is required
when a floating roof is supported by its leg supports be
modified. One cornrnenter (A—97 —17, IV—G-G2) abated that
§63.1063 (b) (2) is confusing and should.be clarified.
Specifically, the commenter stated that §63.1063(b) (2) should
not require continuous filling or emptying when the floating
roof is supported by its leg supports, but should require that
the floating roof be refloated as soon as is practical. Two
commenters (A-97-17, IV-D-02; A-97-17, IV-G-02) recommended
that language in §§63.1063 (b) (2) and 63.1068(c) requiring
recordkeeping of dates when floating roofs are landed and
refloated be deleted. The commenters stated that such
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recordkeeping is not required by any existing regulation and
adds no environmental value.
One commenter (A-97-17, IV-D-02) suggested that
§63.1063(b)(2) include additional language to minimize the time
when a floating roof is landed.
Response: The purpose of the provision in question is, as
one commenter noted, to minimize the amount of time that a
floating roof rests on its legs (or other supports) while a
tank stores liquid. The EPA contends that the noncontinuous
filling of a tank while the floating roof rests on its legs
would not be refloating the floating roof as soon as practical.
The final rule contains the language requiring continuous
filling. The record that includes the date when a floating
roof is rested on its legs and the date it is refloated remains
in the final rule. Without this record, the EPA would have no
information to determine if the length of time a floating roof
rests on its legs is excessive.
Comment: One commenter (A-97-17, IV-D-02) stated that the
description of landing a floating roof should allow for support
devices other than deck legs, including hangers from the fixed
roof. The commenter supplied suggested language for
§63.1063(b)(1) .
Response: The EPA agrees and the final rule includes
language regarding support devices other than legs.
Comment: One commenter (A-97-17, IV-D-02) stated that
internal floating roof tank inspection requirements should only
apply following the first introduction of regulated material
into a vessel that is either newly constructed or has not been
in regulated material service for a year or longer. The
commenter further recommended that this section should not
apply to the temporary introduction of liquid into a vessel due
to episodic or nonroutine events, such as those associated with
startup, shutdown, malfunction, testing, or maintenance
activities. The commenter supplied regulatory text
incorporating their comments. This commenter also recommended
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similar changes (and supplied language) to address inspections
of external floating roof tanks .
Response : The EPA agrees with the first comment, and
"initial filling" in the final rule is defined as the first
introduction of liquid into a storage vessel that is either
newly constructed or has not been in liquid service for a year
or longer. The EPA does not agree that vessels are subject to
inspection only during "permanent" storage. The inspection in
question requires entry into an internal floating roof tank,
which is a confined space. For this reason, it is required
only before the initial filling of a vessel, when the vessel
contains no liquid and has been degassed. If an initial
filling were to occur because of some situation that could not
have been predicted by the owner or operator, then the
inspection likely could not be performed because the vessel
would be a confined space. The inspection requirements would
not apply in these cases of startup, shutdown, or malfunction.
In cases where the initial filling results from scheduled
maintenance or testing, the inspection is required. The
inspection requirements for internal and external floating
roofs have not been revised in the final rule due to this
comment .
Comment: One commenter (A-97-17, IV-D-02) stated that a
cross reference in §63. 1063 (c) (1) (ii) should read (c) (1) (ii) (B)
instead of (c) (1) (ii) (E) .
. '.
Cllivu licio
amended §63. 1063 (c) (1) (ii) of the final rule to read
(c) (I) (ii) (B) instead of (c) (1) (ii) (E) .
Comment : Two commenters (A-97-17, IV-D-02; A-97-17, IV-D-
02) stated that 10-year inspections of external floating roof
tanks should not be required in §63. 1063 (c) (2) (iii) . The
commenter stated that this requirement has not appeared in
previous regulations and is unnecessary since annual
inspections of floating roof secondary seal gaps are required.
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Response: The commenter is correct in that existing rules
have not required the specific inspection every 10 years. In
existing rules, the inspection is required every time a tank is
emptied and degassed. The inspection includes examining
fittings as well as rim seals, and is essentially the same as
the inspection required for internal floating roof tanks any
time they are completely emptied and degassed, or every 10
years, whichever occurs first. The EPA has simply made the
requirements consistent for internal and external floating roof
tanks.
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.1063(d)(3)(iii) should be modified to exempt periods when
secondary seals must be pulled back or removed to inspect a
primary seal.
Response: The EPA agrees, and the final rule states that
the gap specifications do not apply in such cases.
Comment: One commenter (A-97-17, IV-D-02) suggested that
105 days be allowed in §63.1063(e) (2) for repair or removal
from service of a storage vessel. The commenter noted that
this interval would be consistent with the Hazardous Organic
and Refinery NESHAP.
Response: The RON requires repair (or removal from
service) within 45 days, with up to two 30-day extensions where
justified. The EPA proposed a 75-day period (with no
extensions) to ease any administrative burden that may result
from using extensions. The EPA has decided to include in the
final rule the same provisions for repair times that are
included in the HON.
Comment: One commenter (A-97-17, IV-D-02) noted that the
prior notice requirements in §63.1063(d)(2) should not apply to
tank-top inspections.
Response: The EPA agrees, and the final rule does not
require prior notification of such inspections.
Comment: One commenter (A-97-17, IV-D-02) suggested that
the definition of an internal floating roof tank be revised to
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NOT include external floating roof tanks to which a fixed roof
has been added. The commenter stated that this installation of
a fixed roof on an external floating roof tank should be
considered a control option. The commenter also stated that
§§63.1063(a) (1) (ii), (1) (ii) (D), (2) (ii), and (2) (ii) (B) should
require specified rim seals and deck fittings OR require
installation of fixed roofs. The commenter included new
§63.1063 (c) (3) language to address inspection requirements for
a covered external floating roof tank. Another commenter (A-
97-17, IV-G-02) stated that such tanks should be subject to the
inspection requirements for internal floating roofs tanks
instead of the external floating tank inspection requirements.
The commenter also supplied a suggested new §63.1063 (c) (3) to
address such inspections.
Response: External floating roof tanks that have been
covered before the proposal date of this rule are considered to
be internal floating roof tanks for the purposes of this rule,
and must meet the requirements in the rule for such tanks.
Owners or operators of external floating roof tanks that were -
not covered as of the proposal date have several options,
including: 1) meet the requirements for external floating roof
tanks, 2) add a fixed roof and meet the requirements for
internal floating roof tanks, and 3) using the provisions for
alternate means of emission limitation. All covered external
floating roof tanks are treated as internal floating roof tanks
7.6 PRESSURIZED STORAGE VESSEL REQUIREMENTS
Comment: One commenter (A-97-17, IV-D-02) stated that the
pressurized storage vessel requirements of §63.1064 have not
been present in previously-promulgated NESHAP; the commenter
recommended that this section be deleted.
Response: The EPA has decided to remove these provisions
from the final rule. They were included in the proposed
subpart WW not for the source categories that were proposed
with it (in subpart YY), but for future source categories that
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may need such provisions. The EPA has decided to add such
provisions in the future if they are needed.
7.7 PROCEDURE FOR DETERMINING NO DETECTABLE EMISSIONS
Comment: One commenter (A-97-17, IV-D-02) recommended
that references to "cover(s)" be deleted from §63.1067 (a) (1),
(2) , and (7) . The commenter also recommended that "unit" be
replaced with "storage vessel" in §63.1067(a)(1), (2), and (3).
Response: The EPA has decided to remove these provisions
from the final rule. They were included in the proposed
subpart WW not for the source categories that were proposed
with it (in subpart YY), but for future source categories that
may need such provisions. The EPA has decided to add such
provisions in the future if they are needed.•
Comment: One commenter (A-97-17, IV-D-02) stated that
§63.1067(a)(3) should specify that the use of the instrument
response factor criteria in Method 21 is optional and that it
may be used for representative composition instead of average
composition.
Response: The EPA has decided to remove these provisions
from the final rule. They were included in the proposed
subpart WW not for the source categories that were proposed
with it (in subpart YY), but for future source categories that
may need such provisions. The EPA has decided to add such
provisions in the future if they are needed.
7.8 RECORDKEEPING REQUIREMENTS
Comment: One commenter (A-97-17, IV-D-02) stated that
"readily accessible" records in §63.1068 should be clarified to
mean "retrievable within 24 hours" per the Refinery NESHAP.
Response: The EPA disagrees with the commenter that
"readily accessible" should mean "retrievable within 24 hours."
Monitoring data and other records contain important information
that an inspector may need to look at in order to properly
assess a facility's compliance. For the purposes of the
generic MACT rule the EPA defines readily accessible as records
that can be retrieved within 2 hours, as proposed.
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Comment: One commenter (A-97-17, IV-D-02) stated that
records for floating roof landings required in §63.1068 (c)
should only be kept for 5 years.
Response: The EPA agrees, and the final rule contains the
5-year retention time for records of roof landings.
7.9 REPORTING REQUIREMENTS
Comment: One commenter (A-97-17, IV-D-02) stated that the
Notification of Initial Startup required in §63.1069 (a) should
be replaced with an Initial Compliance Status Report to be
submitted with the facility's 6-month Periodic Report.
Response: The EPA has not made the commenter's suggested
change. The commenter's proposed change does not meet the
intent of the part 63 General Provisions. A new source needs
to be in compliance upon startup of such source and to allow
reporting of compliance 6 months after startup would be
unacceptable.
Comment: One commenter (A-97-17, IV-G-05) noted that
§63.1069 (b) is labeled "periodic reports" but includes a
notification requirement. The commenter suggested that the EPA
clarify the notification requirement or make §63.1069 (b) (3) a
separate section.
Response: The requirement of notification of inspection
is done on a periodic basis, and, therefore, is included in the
section for periodic reports.
Comment: One commenter (A-97-17, IV-D-02) stated that the
permitting ciutucrity mciy rsquire a / ^ay prior notice J.OJT
unscheduled inspections under §63.1069 (b) (1) . The commenter
noted the proposed standards would require that tanks taken out
of service for an unplanned repair stand idle for a 15-day
period to provide for sufficient prior notice. The commenter
also noted that the tanks would continue to emit vapors during
this period. Another commenter (A-97-17, IV-G-02) noted a
similar scenario, and suggested that §63.1063 (b) (1) refer to
any "planned internal inspection" rather than "inspection."
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Response: The final rule has been revised to include a 7-
day notice for unplanned inspections.
Comment: One commenter (A-97-17, IV-D-02) stated that
inspection failures [§63.1069(b)(2)] should be reported
semiannually to be consistent with the Refinery NESHAP.
Response: In the final rule, reports of failed
inspections must be submitted with the periodic report required
by the subpart which references subpart WW. The frequency of
these reports are to be determined under the referencing
subpart and not in 40 CFR part 63 subpart WW.
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8.0 GENERIC MACT STANDARDS (40 CFR PART 63, SUBPART YY)
8.1 APPLICABILITY
8.1.1 Flexible Operation Units
Comment: One commenter (A-97-17, IV-G-04) stated that a
demonstration that the parameter monitoring levels established
for the primary product are appropriate for those periods when
products other than the primary product are produced is
inappropriate and unnecessary. The commenter (A-97-17, IV-G-
04) explained that the nature of flexible operations is where
raw materials and products and the nature of the operation
itself is changed. The commenter cited an example where two
different products being produced by the same production chain
are processed differently and the material being vented varies
in pH (neutral and non-neutral) and flow rate (high and low).
The commenter (A-97-17, IV-G-04) explained that it would be
extremely difficult to set parameters that would be applicable
for both products. The commenter also stated that an owner or
operator would have to use the primary product parameters to
meet the requirement for a range for all products and would
incur the costs of doing that with no environmental benefit.
Response: The EPA agrees with the cunimeriter that it cuulu
be difficult, and potentially impossible, to establish a single
parameter monitoring level for all products produced in a
flexible operation unit. In the final rule, at §63.1100(d)(5),
the EPA has clarified compliance options when products other
than the primary product are being produced. First, the option
to control emissions during the production of all products
based on the requirements for the production of the primary
product has been retained. This option includes the
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establishment of a single parameter monitoring level based on
the primary product.
The second option is to determine, for each product
produced in the flexible operation unit, whether control is
required using the applicable criteria in §63.1100 for the
primary product source category. For the production of each
product where control is required, a separate parameter
monitoring level must be established to ensure that the control
requirements are met during the production of that product.
In either instance, the parameter monitoring level(s) must
be submitted in the.Notification of Compliance Status report.
Comment: One commenter (A-97-17, IV-G-04) stated that
§63.1100(d)(4) should be amended to clarify that the
Notification of Compliance Status (NOCS) must also include the
information specified in paragraph (d) (4) (iii) (i.e., material
demonstrating that the parameter monitoring levels established
for the primary product are also appropriate for those periods
when products other than the primary product are produced) of
this section if you have a flexible type operation.
Response: The EPA agrees that a cross-reference
clarification to §63.1100(d)(4)(ii) is warranted. The EPA's
intention was to require an owner or operator of a flexible
operation unit to submit material demonstrating that the
parameter monitoring levels established for the primary product
are also appropriate for those periods when products other than
the primary product are produced if such product is also
subject to the generic MACT rule. Therefore, §63.1100(d)(4)(ii)
of the final rule has been modified to indicate that the
Notification of Compliance Status Report shall include the
information specified in paragraphs (d)(4)(ii)(A) through
(d) (4) (ii) (C) for flexible operation units where more than one
manufactured product is subject to the generic MACT rule.
Paragraph (d) (4) (iii) was changed to paragraph (d) (4) (ii) (C) in
the final rule.
8.1.2 Coordination/Overlap With Other Rules
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Comment: One commenter (A-97-17, IV-G-04) recommended
that the coordination/overlap process equipment provisions of
§63.1100(g) indicate which paragraphs of the referenced rules
apply. The commenter explained that other regulations provide
references to overlapping sections and that inclusion of such
references would avoid necessitating that an owner or operator
make a stringency determination. The commenter recommended
that the EPA prepare tables that clearly define overlaps. The
commenter suggested that the Office of Enforcement and
Compliance Assurance might be able to assist the Office of Air
Quality Planning and Standards in making such determinations.
Response: The EPA has not proposed that an owner or
operator make a stringency determination between two
overlapping rules for storage vessels, equipment leaks, or
process vents. As proposed, the EPA is specifying that an
owner or operator needs to comply with one or the other of the-
overlapping provisions for purposes of compliance with the
generic MACT rule.
The EPA has further clarified specific emission point
affected source overlaps for differing Federal regulations in
the final rule, as appropriate. The format used parallels that
of the RON and Polymer Resins I and IV NESHAPs. The EPA did
not use a table format as suggested by the commenter (A-97-17,
IV-G-04) because the level of detail that would need to be
included in such a table would be more confusing than
Comment; One commenter stated that, under the generic
MACT rule, owners and operators of polycarbonate production
sources have the choice to follow 40 CFR part 63 subpart TT or
40 CFR part 63 subpart UU. The commenter explained that
polycarbonate production sources are currently subject to
subpart I which references the requirements of subpart H.
Section 63.1100 (g) (4) (ii) discusses the overlap of 40 CFR part
63 subpart UU and 40 CFR part 63 subpart H (the HON) but not
the overlap of 40 CFR part 63 subpart TT and 40 CFR part 63
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subpart H. The commenter explained that, as proposed, an owner
or operator subject to 40 CFR part 63 subpart I (40 CFR part 63
subpart H) and 40 CFR part 63 subpart TT would have to comply
with both standards. The commenter requested that the EPA add
a clarification that once the generic MACT rule is promulgated,
polycarbonate sources are no longer subject to 40 CFR part 63
subpart I. The following Polymers and Resins 1 NESHAP standard
was suggested:
After the compliance dates specified in this section, an
affected source subject to this subpart that is also
subject to the provisions of 40 CFR part 63, subpart I, is
required to comply only with the provisions of this
subpart.
Response: It was not the EPA's intent for a source that
is already required to comply with 40 CFR part 63 subpart H or
40 CFR part 63 subpart I to have the option under the generic
MACT rule to .comply with subpart TT in lieu of 40 CFR part 63
subpart H or 40 CFR part 63 subpart I. The intent of allowing
this option was so that a source that is currently complying
with the LDAR requirements that parallel subpart TT or subpart
UU would not be required to change their LDAR system. However,
the EPA does agree, and has amended the promulgated rule to
reflect, that affected sources that are subject to the
equipment leak provisions of 40 CFR part 63 subpart I or 40 CFR
part 63 subpart H, and the equipment leak provisions of 40 CFR
part 63 subpart TT under 40 CFR part 63 subpart YY are in
compliance with 40 CFR part 63 subpart YY if they comply with
the equipment leak provisions of 40 CFR part 63, subpart I or
40 CFR part 63 subpart H or the equipment leak provisions of 40
CFR part 63 subpart TT.
8.2 DEFINITIONS
8.2.1 General Provisions and the Act
Comment: One commenter (IV-D-22) requested that the EPA
reference the definitions of 40 CFR part 63 subpart A and the
Clean Air Act (the Act) in 40 CFR part 63 subpart YY, §63.1101.
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Response : The applicability section of the proposed rule
cross-references the definition section of the part 63 General
Provisions. Nonetheless, the EPA has revised the definitions
section of the final rule to include a reference to the
definitions of 40 CFR part 63 subpart A (part 63 General
Provisions) and the Act. The EPA has made this revision for
clarity and consistency with other part 63 standards.
8.2.2 Closed Vent System
Comment : One commenter (A-97-17, IV-G-04) recommended
that the EPA use the closed vent system definition in the
Synthetic Organic Chemical and Manufacturing Industry (SOCMI)
Consolidated Air Rule (CAR) . The commenter acknowledged that
the definition in the generic MACT rule is the same as in the
CAR with the exception that the CAR added that, for transfer
racks, the closed vent system begins at, and includes, the
first block valve on the downstream side of the loading arm or
hose used to convey displaced vapors.
Response: The EPA agrees with the commenter 's
recommendation and has modified the definition of closed vent
system in the final rule to parallel the closed vent system
definition proposed in the CAR.
8.2.3 Equipment
Comment : One commenter (A-97-17, IV-G-04) stated that the
definition of "equipment" should be revised by adding the
following language after "instrumentation system":
_ _ .. --- _
1_IC J- -L11CU. -Lil
§63.1103 for the applicable manufacturing CMPU.
Response: The EPA has included the commenter 's suggested
language addition to the definition of "equipment" in the final
rule except that the term "CMPU" has been replaced with
language that parallels the CMPU concept under the generic MACT
rule (40 CFR part 63 subpart YY) . The EPA believes that this
change, though unnecessary, clarifies equipment applicability.
8.2.4 Flexible Operations
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Comment: One commenter (A-97-17, IV-G-04) requested that
the EPA change the wording of the definition for "flexible
operations" to allow for reconfiguration of the process by
adding or bypassing unit operation equipment (reactor,
distillation unit, extractor). The commenter explained that
the suggested change would not allow an owner or operator to
add new equipment but would allow an owner or operator to
rearrange existing equipment.
Response: The proposed definition for "flexible
operations" allows the manufacture of "different chemical
products periodically by alternating raw materials or operating
conditions." The proposed definition under the generic MACT
rule (40 CFR part 63 subpart YY), specifically, by allowing
"different operating conditions," does not disallow for
reconfiguration of the process by adding or bypassing unit
operation equipment. Therefore, the EPA has riot made the
commenter's suggested change.
8.2.5 Subsequent Startup
Comment: One commenter (A-97-17, IV-G-04) stated that the
definition for "initial startup" refers to "subsequent startup,
as defined in this section." The commenter stated that a
definition for "subsequent startup" is not included in the
proposed 40 CFR part 63 subpart YY.
Response: The EPA has added definitions of "startup" and
"subsequent startup" in the final generic MACT rule (40 CFR
part 63 subpart YY).
8.2.6 Process Vent
Comment: One.commenter (A-97-17, IV-G-04) stated that
"process vent" is defined as a continuous gas stream and that a
vent is a piece of equipment that can be from a batch
operation. The commenter (A-97-17, IV-G-04) suggested that the
definition be revised to a definition of "process vent stream."
Response: The EPA agrees that, as proposed, the
definition for process vent needs clarification that a process
vent is a piece of equipment that handles both continuous and
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batch gas streams. The EPA has modified the definition of
process vent in the final rule to clarify the EPA's intent.
Comment: One commenter (A-97-17, IV-D-08) requested that
the EPA be consistent in the use of "HAP" and "organic HAP" in
the regulation. The commenter stated that "organic HAP" should
be used in most cases. Another commenter stated that the EPA
should use organic HAP or OHAP in §63.1103(d)(1)(i)(A) and (D)
to avoid confusion regarding what is to be regulated. This
commenter noted that the EPA has not made clear if they intend
to regulate the emissions to regulate non-organic HAP.
Response: The EPA agrees with the commenter and has
assessed the use of HAP and organic HAP throughout the
rulemaking package and has made changes, as appropriate in the
final rule.
Comment: One commenter (A-97-17, IV-D-08) requested that
storage tanks be expressly excluded from the definition of
"process vents." The commenter also stated that "process
vents" should exclude low organic HAP streams. The commenter
supplied an alternative "process vent" definition addressing
both comments.
Response: The EPA agrees with the commenter that storage -
vessels should be expressly excluded from the definition of
"process vents," therefore, the EPA has revised the final rule
to distinguish process vents and storage vessels.
8.2.7 Process Unit Shutdown
Comment; One commenter (A-97-17, IV-G-04) suggested that
there should be an allowance for a scheduled work practice of
short duration included in the definition of "process unit
shutdown." The commenter (A-97-17, IV-G-04) contended that it
may be necessary to schedule short shutdowns to make minor
repairs or adjustments to a piece of process equipment. The
commenter (A-97-17, IV-G-04) stated that this option is allowed
in other MACT standards (e.g., for storage vessels). The
commenter (A-97-17, IV-G-04) maintained that it is often safer
and more environmentally beneficial to perform maintenance on
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control and recovery devices without shutting down the entire
process, because many continuous processes can require days to
start-up and shutdown. The commenter (A-97-17, IV-G-04)
provided 3 examples where they claimed that the emissions from
a shutdown and subsequent start-up of the process would be
greater than if the control devices had been serviced while the
processing continued.
Response: The EPA considered the commenter's (A-97-17,
IV-G-04) suggested change that there be an allowance for
scheduled work practice of short duration in the definition of
"process unit shutdown," and decided to make no change in the
final rule. The EPA has provided allowances for routine
maintenance of control devices in some rules, but only for very
unusual situations. (In these cases, a time limit was
specified). The storage vessel control device situation
mentioned by the commenter is a good example. In general, the
EPA expects routine maintenance on control devices to occur at
the same time process equipment is shutdown for maintenance, or
that control system configurations are planned to provide for
routine maintenance. Storage vessels are unusual because
emissions occur as long as they contain liquids. There is no
reason to expect the storage vessels to be empty during periods
when other process equipment is shutdown for maintenance. It
is difficult to know without more facts, but some of the
examples described by the commenter could potentially be
malfunctions that should be covered in a startup, shutdown, and
malfunction plan.
8.2.8 Recovery Device
Comment: One commenter (A-97-17, IV-G-04) stated that the
proposed definition for "recovery device" has a duplicate use
of the term "reuse." The commenter also pointed out that there
seems to be an extraneous sentence relating to "recapture
device."
Response: The EPA agrees that there is a duplicate use of
the term "reuse" in the proposed rule that was unintended and
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has deleted one of the terms in the final rule. However, the
sentence that the commenter believed was extraneous regarding
the monitoring, recordkeeping and reporting requirements is an
intentional clarification. Recapture devices are control
devices, except for the purposes of monitoring, recordkeeping
and reporting requirements. For purposes of monitoring,
recordkeeping and reporting requirements, recapture devices are
considered recovery devices.
8.2.9 Transfer Rack
Comment: One commenter (A-97-17, IV-G-04) commented that
the definition for "transfer rack" should not include the
loading of marine vessels since this would be regulated under
the Marine Vessel MACT standard.
Response: The EPA agrees with the commenter that loading
of marine vessels will be regulated under the Marine Vessel
MACT standard. Therefore, the EPA has excluded the loading of •'
marine vessels from the definition of "transfer rack" in the
final rule.
8.2.10 Add Definitions
Comment: One commenter (A-97-17, IV-G-04) requested that •
the EPA add definitions for the following terms:
• compliance equipment,
excess emissions,
• fuel gas,
• fuel gas system,
• product,
• shutdown,
• research and development facility,
• startup, shutdown, and malfunction plan,
• excursion, and
• excused excursion.
The commenter (A-97-17, IV-G-04) explained that these terms are
used in 40 CFR part 63 subpart YY but are not defined. The
commenter (A-97-17, IV-G-04) suggested that definitions from 40
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CFR part 63 subpart A, the RON, and the CAR be used. The
commenter (A-97-17, IV-G-04) noted that they were unable to
find definitions for the terms "excursion" and "excused
excursion" in 40 CFR Part 63 subpart A, D, F, or H.
Response: The EPA acknowledges that inclusion of most of
the suggested definitions or clarification of their meaning
within the text of the final generic MACT rule would serve to
better clarify the intent of the rule. Many of the definitions
included in the final rule were adopted from 40 CFR part 63
subpart A, the HON, and the CAR. Therefore, the EPA has
included the suggested definitions, or included clarifications
(i.e., .for excursion, and excused excursion) of their meaning
in the final rule. Regulatory text clarifications of .an
excursion include instances when the source is outside of the
monitoring parameter range or when there is insufficient
monitoring data to determine compliance. Excused excursions
are excursions that result from a startup, shutdown or
malfunction and are included in an owner or operator's approved
SSM plan.
The EPA has not added a definition for "compliance
equipment" because this term is meant to include, as
appropriate, both emissions control equipment used to meet an
emission limit requirement and monitoring equipment used to
demonstrate that a required emission limit is met. The EPA
believes that the use of "compliance equipment" within the
regulatory text of the rule is adequate to explain the intent
of its use.
The EPA has not added a definition for "startup, shutdown,
and malfunction plan" in the final rule because the EPA
believes requirements for this plan adequately define what the
plan is. Additionally, the final rule includes definitions for
the terms "startup," "shutdown," and "malfunction."
8.3 COMPLIANCE SCHEDULE
Comment: One commenter (A-97-17, IV-G-04) suggested that
§63.1102(a) (iv) be re-written for clarity or eliminated. The
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commenter explained that the Act indicates that section 112(f)
standards be effective on promulgation. The commenter stated
that, as proposed, it is unclear whether the EPA meant to allow
constructed or reconstructed sources a different compliance
period than those sources that were not constructed or
reconstructed.
Response: The EPA agrees with the commenter that
§63.1102 (a) (iv) should be re-written for clarity or eliminated.
Upon evaluation, the EPA decided that it was unnecessary and it
was deleted.
Commenter: One commenter (A-97-17, IV-D-01) supported the
proposal that 3 years be provided from the effective date of
the rule for existing sources to meet the compliance
requirements.
Response: The EPA appreciates the commenter"s support (A-
97-17, IV-D-01) and has maintained the 3-year compliance date ,•
in the promulgated rule.
8.4 SOURCE CATEGORY-SPECIFIC APPLICABILITY, DEFINITIONS, AND
REQUIREMENTS
8.4.1 Acrylic and Modacrylic Fiber Production
Comment: According to commenter IV-G-1, add-on controls
for existing spinning lines at solution polymerization
processes are not warranted for a variety of reasons. These
include the fact that add-on enclosures and control devices are
not technologically feasible for existing spinning lines and
the pollution prevention measures applicable to other processes
are not capable of achieving the required emission reductions
at existing solution polymerization processes. The commenter
provided numerous reasons why both enclosures and conventional
add-on controls are not warranted and technically feasible at
existing solution polymerization AMF spinning lines. For
example, the commenter cited the technical complications
resulting from low volatility of the non-HAP solvent present
and the low concentration of AN in the exhaust stream in
support of their contention. The commenter also pointed out
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that the spinning line applicability cut-off (i.e., 100 ppmw in
the spin dope) used in the proposed rule was not appropriate
for solution spinning operations and provided technical
analysis in support of this view. In addition, the commenter
stated that given the technical limitations related to control
of HAP emissions at existing solution polymerization spinning
lines, that EPA significantly under estimated the cost of
controlling these units.
Response: The EPA has considered the comments and the
technical information and data submitted in support of the
comments and as revised the final regulation to take into
account the technical limitations associated with control of
existing solution polymerization spinning lines. The EPA's
rationale for these revisions are discussed in the preamble to
the final rule. Based on the changes to the final rule (i.e.,
no control for existing AMF solution polymerization spinning
lines), the associated comments regarding cut-off levels,
measurement methods, enclosure specifications, emission
reductions, health and safety risks, and costs are no longer
relevant and therefore are not discussed in this document.
8.4.2 Hydrogen Fluoride Production
Comment: One commenter (Docket No. A-97-17-, Comment No.
IV-D-04) submitted that "hydrogen fluoride" and "hydrogen
fluoride production" should be defined more precisely in
§63.1103(c)(2). According to the commenter, the term hydrogen
fluoride (HF) properly defines anhydrous HF, but is sometimes
used to describe aqueous solutions of HF. The commenter
believes that EPA intended to regulate only anhydrous HF,
particularly considering the difference in vapor pressure of
anhydrous HF and aqueous solutions of HF (the commenter stated
that the vapor pressure of HF drops below 0.3 kilopascals at 20
°C when its strength drops below 99.6 percent). The commenter
further stated that HF vapor pressures decline rapidly with the
addition of minor amounts of water, thus, little value is
gained by the inclusion HF other than anhydrous, since the
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vapor pressures of HF solutions result in no significant
emissions. The commenter suggested definitions for "hydrogen
fluoride" and "hydrogen fluoride production" that would limit
the rule's applicability to anhydrous HF.
Response: The EPA's intent is to regulate HF emissions
from the production of both anhydrous and aqueous HF. The EPA
disagrees that the vapor pressures of aqueous solutions of HF
are "insignificant." Information gathered from site visits to
HF producers during the development of presumptive MACT
indicated that the commercial grade of aqueous HF that is
currently produced contains 70 percent HF. The vapor pressure
of aqueous HF (70%) at 25 °C is 20 kilopascals (Docket No. A-
96-54, Item No. II-A-4) and it is noted in this document that
an HF vapor cloud may form under some conditions from a release
of an aqueous solution of HF. Therefore, the definition of HF'
is not being added as requested by the commenter, nor is HF
production limited to production of anhydrous HF.
Comment: One commenter (A-97-17, IV-D-05) observed that
for the four source categories subject to the proposed rule,
the EPA specified no weight percent cutoff for HF for the
applicability of a leak detection and repair (LDAR) program,
unlike those for the other GMACT categories where weight
percent cutoffs are specified. The commenter submitted that
not establishing a threshold below 10 weight percent HAP
concentrations would affect process and waste lines of
insignificant concentration and impose undue costs, principally
for monitoring, for the relatively small benefits obtained.
The commenter recommended that the EPA set a threshold level of
10 weight percent HF to trigger the application of LDAR to
equipment leaks in HF service.
Response: Although the equipment leak requirements of the
HF production MACT apply to any equipment that contains or
contacts HF, the applicability of the HF production MACT is to
emission points associated with a HF production process unit
located at a major source as defined in section 112 (a) of the
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Act. Therefore, the equipment leak requirements apply to
process equipment associated with the HF production process,
which will contain and contact HF vapors and HF liquids
containing high concentrations of HF. Wastewater treatment
systems, which contain dilute HF solutions, are not included in
the emission points covered by the standard [refer to Table 1
to §63.1100. - Source Category MACT Applicability at 63 FR
55264 (Oct. 14, 1998)]. Furthermore, the State air emission
permits of the currently operating HF production facilities do
not specify concentration cutoffs defining the applicability of
equipment leak LDAR requirements. The EPA anticipates little,
if any equipment covered by the rule would fit the commenter's
description..
Comment: One commenter (A-97-17, IV-D-04) requested that
in §63.1103 Table 4 Item 1, venting from storage vessels should
be clarified to apply only to normal operations. The commenter
submitted that it should be explicitly stated that "venting"
refers to the displacement emissions created by normal filling
or emptying activities and not other activities such as
emergency or upset conditions that are best covered under
startup, shutdown, and malfunction requirements.
Response: The EPA agrees that the control requirements for
venting from storage vessels were only intended to apply to
normal operations and should be clarified. The requirements
for a storage vessel in §63.1103 Table 4 Item 1 have been
revised to read as follows, "reduce emissions of hydrogen
fluoride by venting displacement emissions created by normal
filling or emptying activities through a closed-vent system to
a recovery system or wet scrubber that is designed and operated
to achieve a 99 weight-percent removal efficiency." Emissions
created by emergency or upset conditions (e.g., from a pressure
release) must be addressed by procedures in the facility
startup, shutdown, and malfunction plan as specified in
§63.1111.
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Comment: One commenter (A-97-17, IV-D-04) suggested that
the requirement of §63.1103, Table 4, Item 3 be removed in its
entirety and that emergency venting from kiln seals be handled
under startup, shutdown, and malfunction plans. The commenter
noted that the kilns normally operate under vacuum and that
emissions from kiln seals occur very infrequently, and only
under process upset conditions. The commenter further noted
that the kiln seals are designed to withstand positive pressure
events of up to 2 inches of water column and that operating
controls and systems installed in the plant have practically
eliminated the positive pressure events that would result in
emissions from the kiln seals. The commenter described the
emission capture and scrubbing system (with approximately 90
weight percent removal efficiency) that has been installed on
the kiln seals to control emergency situations outside of
routine operations and the plan to immediately shut down the
kilns at the onset of a significant positive pressure event.
Response: The EPA agrees with the commenter that kiln seal
emissions are associated only with process upset conditions,
and therefore, more appropriately should be handled under the
facility startup, shutdown and malfunction plan. Consequently,-
kiln seals have been removed from the list of emission points
included in the hydrogen fluoride production source category
affected source at §63.1103 (c) (1) (i) and correspondingly from
§63.1103, Table 4. A statement has been added to the reference
in §63.1103 (c) (3) to 563.1111 (Startup, Shutdown, and
Malfunction) requiring that control of hydrogen fluoride
emissions from kiln seals during upset conditions must be
addressed in the startup, shutdown, and malfunction plan.
Comment: One commenter (A-97-17, IV-D-04) submitted that
with respect to §63.1103, Table 4, Item 5, walk-throughs should
be conducted on a "per shift" frequency. The commenter noted
that unlike VOC leaks, HF process leaks are readily detectable
by smell and sight so that there is little need to perform
frequent detailed inspections. The commenter stated that the
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inspection frequency discussed and proposed in presumptive MACT
was "once per shift," which also is noted on page 55193 of the
preamble to this proposed rule. The commenter's facility works
12 hour shifts, therefore the commenter requested that the
"once per shift" requirement be reinstated in place of the 8
hour requirement. The commenter also noted that most leaks are
detected and repaired from routine walk throughs by operating
personnel. The commenter has conducted periodic component-by-
component inspections that consistently indicate leak rates
less than 0.2 percent, showing that walk throughs are effective
in maintaining low leak rates. Therefore, the commenter
suggested that the term "inspection" in Item 5 be changed to
walk through or similar term, since inspection connotes viewing
closely and is more frequently associated with a component-by-
component examination. Finally, the commenter noted that
§63.1004(d) defines sensory monitoring methods as "visual,
audible, olfactory, or any other detection method", whereas
Table 4 requires "visual and olfactory detection inspections"
and requests that consistent terminology be used.
Response: The EPA agrees that the intent of the leak
detection requirement is for a walk-through inspection to be
conducted once per shift. Also, as is noted in the PMACT
document (Docket No. A-96-54, Item No. II-E-3), the walk-
through inspection should not be a comprehensive component-by-
component inspection. To clarify EPA's intent, the PMACT
terminology for the required leak detection and repair program
has been incorporated into the final equipment leak
requirements at §63.1103, Table 4, Item 4, and the cross-
references to the requirements of §§63.1004(d) and 63.1005 of
subpart TT have been removed. To insure consistency and
clarity of the terminology used, definitions needed to describe
the equipment leak detection and repair program have been added
to §63.1103 (c) (2), including a definition for sensory
monitoring as follows: "sensory monitoring means the detection
of a potential leak to the atmosphere by walk-through visual,
8-16
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audible, or olfactory monitoring. Comprehensive component-by-
component inspection is not required." The revised §63.1103,
Table 4, Item 4 provisions for equipment include the
requirement that the owner or operator perform sensory
monitoring at least once every shift.
Comment: One commenter (A-97-17, IV-D-04) suggested that
although it is industry .practice to use wet scrubbers for HF
removal, other technologies may exist which provide equivalent
performance. The commenter believes that restricting control
technology to wet scrubbers prohibits installation of
innovative or alternative technology. The commenter
recommended that in §63.1103, Table 4, Items 1, 2, and 4, the
phrase "wet scrubber that achieves a 99 weight-percent removal
efficiency" be amended to include the following language: "or
other system that achieves equivalent control".
Response: The regulation, at §63.1103 (c) (3), already
provides for alternative means of emission limitations under
§63.1113. There is no need to restate that provision each time
wet scrubbers are identified in the table.
Comment: One commenter (A-97-17, IV-D-04) pointed out
that §63.1103, Table 4, Item 5 refers to §63.1101 for the
definition of equipment requiring a leak detection program.
The commenter believes that it is EPA's intent to apply the
equipment leak regulations to systems that are a part of normal
operations and not systems which handle infrequently occurring
or highly improbable emissions, ouch as, emergency systems
downstream of pressure relief devices. According to the
commenter, it would be a poor use of resources to monitor and
inspect equipment that never or rarely contain HF.
Response: The EPA inadvertently failed to reference the
exemptions to the requirements of 40 CFR part 63, subpart TT
for equipment leaks, which are codified in §63.1000(c) and
include an exemption for equipment in service less than 300
hours per calendar. This exemption is intended to limit
application of the equipment leak requirements to systems that
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are a part of normal operations. Section 63.1000 (c) also
provides an exemption for equipment in vacuum service. The
final rule incorporates the exemptions of §63.1000 (c) by
stating in §63.1103, Table 4, Item 4 that equipment is subject
to the leak detection and repair requirements if "it is in
hydrogen fluoride service and operates z 300 hours per year and
is not in vacuum service." Equipment that is excluded from
sensory monitoring because it operates less than 300 hours per
year or is in vacuum service must be identified by list,
location, or other method and a record kept of the equipment
identity.
Comment: One commenter (A-97-17, IV-D-04) questioned the
inspection requirements for closed-vent systems. The commenter
no.ted that §63.983 (b) requires initial and annual inspection of
closed-vent systems and suggested that little additional
benefit is provided in light of the "per shift" walk -throughs
that provide virtually constant detection considering the
olfactory properties of HF and the visual detection techniques
for HF leaks. The commenter also believes that the method
required by §63.983(c) for closed-vent system inspection is
incorrect, i.e., sensory monitoring methods should be required
for HF systems rather than the Method 21 inspection required by
§63.983(c) (1) .
Response: The inspection requirements for closed-vent
systems were inadvertently incorporated by referencing the
requirements of 40 CFR part 63 subpart SS in the proposed rule.
The definition of equipment, which includes any control devices
or closed-vent systems used to comply with this subpart has
been added to §63.1103(c)(2) and the appropriate inspection
requirements for equipment in hydrogen fluoride service have
been added to §63.1103, Table 4, Item 4 of the final rule,
eliminating the redundant inspection frequency and the
requirement for Method 21 inspection for closed-vent systems.
Comment: One commenter (A-97-17, IV-D-04) expressed the
opinion that HF scrubbers should not be regulated as "halogen
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scrubbers" under §63.994 (c). The commenter submitted that
scrubbers removing fluorides and chlorides function
differently, have different critical control parameters, would
logically have different periodic monitoring requirements, and
thus should be regulated separately. The commenter believes
that the monitoring requirements for halogen scrubbers appear
to be directed at scrubbers which may be present in organic
manufacturing processes. The commenter offered two examples
of monitoring requirements established by §63.994 (c) that are
not applicable to HF scrubbers, i.e., the pH and the inlet flow
monitoring requirements. Regarding pH monitoring, the
commenter claimed that in his facility, water is recycled for
many uses including scrubber medium for process and other
scrubbers. In the course of the various uses in the plant, the
water assumes a low pH, yet still has excellent absorbing •,
capacity for HF. The commenter noted that there are no
noticeable pH changes across the scrubbers. Accordingly, the
use of a pH monitoring device to monitor the pH of scrubber
effluent would provide no benefit in a HF production facility.
The commenter contrasted the fact that HF is successfully
removed in a water scrubber due to its great affinity to water
to the case of scrubbing HC1, where free alkali is required to
chemically precipitate the chloride to affect removal. With
respect to monitoring inlet flow rate, the commenter stated
that vents in HF production facilities typically maintain very
low flow rates and that reverse flow may sometimes be observed
in some vents. The commenter added that the sensing element of
any flow monitoring device would have to be constructed of
exotic materials to withstand the aggressive nature of the in-
process streams and that reliable operation would probably be
difficult to maintain. The commenter believes that the most
effective and reliable indicator of removal efficiency is
scrubber liquor inlet flow and notes that the plant's current
air operating permits stipulate minimum required flows and
monitoring thereof. The commenter requested that the EPA
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reference the specific applicable sections of 40 CFR subpart SS
or simply describe separately the requirements for HF scrubbers
or alternate removal devices.
The commenter also submitted that application of the
§63.994(c) monitoring requirements and the referenced
recordkeeping requirements of §63.998 (b) to kiln seal scrubbers
is even more burdensome. The commenter stated that although
these scrubbers "operate" continuously, they are not "in
service" except during upset conditions, which occur very
infrequently, if ever. The commenter stated that EPA
recognizes that equipment in service infrequently should be
excluded in subpart TT and requests that similar language be
added to exclude kiln seal scrubbers from the monitoring and
recordkeeping requirements of subpart SS.
Response: The EPA agrees that the requirements for halogen
scrubbers in subpart SS that were referenced in the proposal
are directed at scrubbers which may be present in organic
manufacturing processes and are inappropriate for HF scrubbers.
Because hydrogen fluoride is very soluble in water, it is
easily removed from a vent stream by water scrubbing. The key
parameter in determining the HF removal efficiency of a
scrubber for this process is the flow rate of water to the
scrubber. Consequently, the cross reference to the
requirements of 40 CFR part 63, subpart SS has been removed and
the requirements for HF scrubbers identified in the PMACT
document (Docket No. A-96-54, Item No. II-E-3) have been
incorporated into §63.1103, Table 4, Item 1. The revised
language of Table 4', Item 1 requires that a wet scrubber to
which emissions of hydrogen fluoride are vented be designed and
operated to achieve a 99 weight-percent removal efficiency.
Continuous monitoring of only the scrubber liquid inlet flow
rate is required to ensure that operation of the scrubber is
maintained within design specifications. The owner or operator
must determine the minimum scrubber liquid flow rate that will
ensure a 99 weight percent removal efficiency. In addition to
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the general requirements for monitoring, reporting, and
recordkeeping contained in subpart YY, the general monitoring
requirements of §63.996 apply, and monitoring data must be
handled as specified in §63.998 (b) and records specified in
§63.998 (c) and (d) (3) maintained. Reports must be submitted as
required in §63.999 (b), as applicable.
Regarding the proposed monitoring and recordkeeping
requirements for kiln seal scrubbers, as was explained in a
previous response, kiln seals have been removed as an affected
emission point, therefore there are no monitoring and
recordkeeping requirements for kiln seals, except as specified
in the startup, shutdown, and malfunction plan required by
§63.1111. It is noted that the plan must address minimization
of kiln seal emissions, and record and report such occurrences •
as described in §63.1111.
8.4.3 Polycarbonate Production
Comment: One commenter (A-97-17, IV-G-04) stated that the
EPA has not justified that control requirements are needed for
storage vessels having a capacity of less than 8 cubic meters
(2,113 gallons). The commenter noted that the EPA does not
offer any rationale why controls beyond those required by
existing NESHAP are required for these size tanks, and requests
that control requirements for these tanks be consistent with
the HON. The commenter later noted that there seemed to be
contradictions between the discussion in the preamble and the
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commenter supplied alternative text to address their concerns.
Response; The EPA agrees that most existing NESHAP have
not required controls on small tanks (capacity less than 75
cubic meters [20,000 gallons]), mainly because it is not
usually cost-effective to do so. However, some small tanks in
the polycarbonate industry are controlled. Before proposal the
Generic MACT standard, the EPA developed Presumptive MACT for
polycarbonate production. Since some small tanks were
controlled, the EPA calculated a floor for such tanks for
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purposes of Presumptive MACT. The proposed standard for
existing small polycarbonate tanks was based on this floor.
This presumptive floor was difficult to calculate because there
are few small tanks. For this reason, the EPA did not use the
presumptive floor in the final rule, but considered the impacts
of controlling small tanks. In the New Source Performance
Standards (NSPS) for volatile organic liquids (40 CFR 60,
Subpart Kb), and in the RON, environmental and cost impacts
were analyzed to determine whether to require control of small
tanks. Based on those impacts, the NSPS has no control
requirements for tanks smaller than 75 cubic meters, nor does
the HON for existing small tanks. For this reason, the final
subpart YY has no control requirements for existing small tanks
at polycarbonate facilities.
As discussed above, there is no clear basis upon which
sources are controlling small tanks, making a new source floor
determination ambiguous. Therefore, the EPA has decided in the
final rule to address small tanks as they were in the HON.
Comment: One commenter (A-97-17, IV-D-08) stated that the
definition of "affected source" in §63.1103(d)(1)(i) is overly
broad and could be applied more broadly then intended. The
commenter also stated that the definition of "affected source"
in this section should reflect that phosgene production units
are a part of the polycarbonate production category. The
commenter submitted an alternative "affected source" definition
to address these comments as well as some clarifications in the
general readability of the definition.
Response: The EPA agrees, and the final rule more clearly
describes phosgene production units in the definition of
"affected source."
Comment: One commenter (A-97-17, IV-D-08) stated that the
definition of "polycarbonates production" in §63.1103 (d) (2)
should consistently refer to the singular "polycarbonate"
rather then the plural "polycarbonates." The commenter also
noted that catalysts besides pyridine could be used in
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polycarbonate manufacturing, and stated that the definition
should reflect this. The commenter supplied alternative
language for this definition incorporating these comments.
Response: The EPA agrees; therefore, the EPA has made the
suggested changes in the final rulemaking package.
Comment: One commenter (A-97-17, IV-D-08) stated that the
TRE index value cutoff for monitoring (table 5 of §63.1103)
should be lowered from 4.0 to 3.5. The commenter stated that
the EPA had estimated the commenter's TRE index values to be
higher than 4.0 in the EPA's Presumptive MACT analysis. The
commenter stated that they had new emissions data which results
in TRE indices less than 4.0. The commenter states that their
plants emit less than other plants on an emissions-per-
production basis, and should not be subject to monitoring.
Response: An owner or operator of a process vent with a•
TRE index value between 2.7 and 4 is required to monitor
parameter values to assure that they are operating in such a
way that they will not become subject to control requirements,
or to provide the information to indicate that the TRE index
value vent has gone below 2.7. The TRE index "cushion" between
2.7 and 4 is smaller than the cushion of 3 in the HON. It is .
smaller because the EPA does not expect variations in the
volume and mass flows of polycarbonate vent streams to be large
enough to require the larger cushion. TRE index inputs from
the new emission tests performed by the commenter result in
in^i*"*£*Q t^a^ di^^er bw as much as 1. The TRE ind^x >^f>^-^ff for
monitoring in the final rule is 4.
Comment: One commenter (A-97-17, IV-D-08) suggested making
several references to TRE index values generic in several
sections of the regulation. The commenter stated that such
modifications would accommodate future referencing subparts.
The commenter suggested modifications to §§63.981, 63.993 (c),
63.998 (c) (3) (i), 63.1101, 63.1104(k) (1), and 63.1104 (k) (2) .
Response: The EPA has not made the commenter's suggested
change at this time but will consider it with future proposals
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if future categories are regulated under the generic MACT rule
that apply a TRE index value applicability and compliance
level.
Comment: One.commenter (A-97-17, IV-D-08) stated that the
distinction between halogenated and non-halogenated vent
streams produces a negative impact. Specifically, when a
facility lowers the halogen content of a stream below 0.45
kg/hr, the control requirement may be triggered. The commenter
noted that this could create a disincentive to emissions
reduction for halogenated compounds. The commenter suggested
that the distinction between halogenated and non-halogenated be
removed and that the proposed Table 8 coefficients for
"halogenated" vent streams be used for all vent streams. The
commenter alternatively suggested lowering the total halogen
concentration cutoff from 0.45 kg/hr to a point where the
negative effect no longer occurs.
Response: The EPA agrees there is an inherent
discontinuity in the TRE equation caused by changing the
equation coefficients when the halogen content of a vent stream
is reduced below 0.45 kg/hr of halogen atoms. The EPA agrees
that this could be a disincentive for owners and operators to
reduce the halogen content of their streams because they may
become subject to control requirements from the use of the
equation coefficients for nonhalogenated streams. Lowering the
cutoff that defines a halogenated stream to below 0.45 kg/hr of
halogen atoms would merely shift the discontinuity. Although
not all vent streams in the polycarbonate source category
exceed 0.45 kg/hr of halogen atoms, nearly all vent streams in
the polycarbonate source category contain halogenated solvents
(typically methylene chloride).
The option of using only the halogenated coefficients in
the TRE equation is viable and would remove the disincentive
caused by the equation discontinuity. This option would not
change the applicability (of emission control) status of the
vent streams in the polycarbonate source category. The final
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rule specifies that the halogenated coefficients be used in the
calculation of TRE index values.
Comment: One commenter (A-97-17, IV-G-04) stated that the
EPA should clarify if 20 ppm TOC is an acceptable level of
control in the first row of Tables 5 and 6 of §63.1103.
Response: The 20 ppm option is included for process
vents, but was included for storage vessels in error. The 20
ppm option is usually an option for process vents, where
continuous compliance with a 98% performance standard may be
difficult for streams with low concentrations. Since the rule
requires 95% control for storage vessels, the 20 ppm option
would be less stringent only when the concentration of the
vapor stream is less than 400 ppm. It is unlikely that a vapor
stream from a storage vessel with a saturated vapor space would
be below this low level. The final rule does not include the.,.
20 ppm option for storage vessels.
Comment: One commenter (A-97-17, IV-G-04) stated that Item
2 in Tables 5 and 6 of §63.1103 does not include options for
flares, internal floating roofs, external floating roofs, and
pressure vessels as acceptable controls. The commenter
encourages the EPA to include these measures and questioned if.
the EPA omitted them unintentionally. The commenter suggested
adding the following language: "Comply with the storage vessel
control requirements of §63.1062 (a) (3)- (a) (8) of 40 CFR Subpart
WW of this part. If venting emissions through a closed vent
system tc 3. ncn—flcirs control device, reduce emissions of OKAP
by 98 weight percent, or to an outlet concentration of 20 ppmv,
whichever is less stringent."
Response: The EPA did unintentionally omit flares as a
control option for storage vessels, but the floating roofs were
intentionally omitted. Based on information available to the
EPA, all storage vessels larger than 151 cubic meters (40,000
gallons) are controlled by combustion. The floor, therefore,
did not allow using floating roofs, which are unlikely to
achieve the same level of control. The provisions for pressure
8-25
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vessels were removed. They did not apply to any of the vessels
in the source categories proposed with the GMACT, but were
included for future use by other source categories. The EPA
may add such provisions in the future to Subpart WW if needed.
Comment: One commenter (A-97-17, IV-G-04) noted several
editorial corrections in Tables 5 and 6 of §63.1103.
Response: The EPA has amended the tables in the final
rule, therefore many of the suggested changes no longer apply.
8.5 PROCESS VENTS FROM CONTINUOUS UNIT OPERATIONS;
APPLICABILITY DETERMINATION PROCEDURES AND METHODS
Comment: One commenter (A-97-17, IV-D-08) stated that the
reference to combined streams in §63.1104(d)(1) is unclear
regarding the operating conditions under which stream
characteristics are determined for use in TRE index
calculations.
Response: The EPA agrees. The final rule includes a
definition of "combined vent stream." Combined vent streams
are treated as vent streams from continuous unit operations,
except that stream properties for combined vent streams are.
determined under maximum representative operating conditions.
The final rule reflects this.
Comment: One commenter (A-97-17, IV-D-08) stated that the
provisions whereby a source could seek a low-HAP concentration
exclusion under §63.1104 (e) (2) (vi) are overly burdensome and
should be deleted. The commenter noted that: (1) measurements
sho.uld be based on HAP not TOC; (2) methane and ethane should
be excluded from the concentration cutoff calculations; and (3)
the measured value should be compared to the applicability
concentration - not one-half of the applicability
concentration. The commenter supplied suggested text to
address their comments.
Response: The final rule allows an owner or operator a
choice between complying with a specified emission limit
reduction or by meeting a 20 ppmv TOC concentration limit where
such an allowance was intended by the EPA. If it is considered
8-26
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by the commenter to be overly-burdensome, the commenter can
meet the specified emission limit, as appropriate. The EPA has
not deleted this exclusion allowance where such allowance has
been determined to be an appropriate exclusion option.
Comment: One commenter (A-97-17, IV-D-08) noted that the
low HAP concentration exclusion provisions of §63.1104 do not
appear to be referenced by any of the tables in the proposed
rule. The commenter questioned the validity of these
exclusions.
Response: The EPA has eliminated the low HAP
concentration exclusion from.the final rule. This low HAP
concentration exclusion was an error.
8.5.1 Repropose §63.1104
Comment: One commenter (A-97-17, IV-G-04) suggested that
the EPA repropose §63.1104 because of cross-reference errors
that made it difficult for them to fully determine the impact^
and compliance requirements of this section on their facility.
Response: The EPA assessed the cross-reference errors
identified by the commenter and determined that the errors did
not warrant reproposal of §63.1104. There was one misplaced,--
one wrong, and two missing cross-references. The missing and
wrong cross-reference errors were cross-referencing
requirements that were specified in the sentences that had the
errors (e.g., "record the TOC or HAP concentration as specified
in paragraph."). The misplaced cross-reference error led to a
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unnecessary and led to confusion. Cross-reference errors are
addressed in section 8.6.
8.5.2 Batch Unit Operations
Comment: One commenter (A-97-17, IV-G-04) stated that the
title of §63.1104 (a) and the description of the purpose of the
paragraph should show that it is referring to a stream that has
both batch and continuous process vent emissions. The
commenter requested that the EPA rename the paragraph and
propose to correctly show that requirements to determine the
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maximum operating conditions must be based on the continuous
operation plus those where a batch unit also vents to the
continuous vent.
Two commenters (A-97-17, IV-G-04; A-97-17,
IV-D-01) had comments on the reference to "combined stream."
One commenter (A-97-17, IV-G-04) suggested that "combined
stream" be defined as a stream where maximum operation
conditions must be based on both continuous unit operations and
where a batch unit operation vents to a continuous unit
operation process vent. The other commenter (A-97-17, IV-D-01)
stated that the basis for the use of the phrase "combined
stream" is unclear and needs to be clarified. The commenter
(A-97-17, IV-D-01) suggested language for a definition of
"combined vent stream."
One commenter (A-97-17, IV-D-01) suggested language to
clarify "peak emission episodes" and "emission profiles" under
§63.1104(d).
Response: The EPA has eliminated the process vents from
batch unit operation provisions from the final rule because
there are no longer any process vents solely from batch unit
operations that will be subject to the generic MACT rule.
However, a definition for "combined vent stream" has been added
to the final rule because there are process vents from both
batch and continuous unit operations that will be subject to
this rule. Furthermore, the EPA has clarified and streamlined
the combined vent stream requirements in the final rule as
requested by the commenter.
The EPA will include provisions for process vents from
batch unit operations in future proposals, as necessary.
Comments received on the proposed provisions for process batch
unit operations under the generic MACT rule will be considered
if the EPA proposes such provisions in future proposals.
8.5.3 Test Method 26 or 26A
Comment: One commenter (A-97-17, IV-G-04) stated that
§63.1104(1)(1)(iii) is not in agreement with the preamble or
8-28
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other applicable sections because it directs an owner or
operator to measure the concentration of organic compounds
containing halogens or hydrogen halides as measured by Method
18 of part 60, appendix A rather than Method 26 or 26A of part
60, appendix A. In order to parallel §63.1105 (c) (1) (iii) and
the preamble, the commenter suggested that the paragraph be
rewritten as follows:
Concentration of organic compounds containing halogens or
hydrogen halides as measured by Method 26 or 26A of 40 CFR
part 60, appendix A.
Response: Method 18 of 40 CFR part 60 appendix A applies
to the analysis of gaseous organics, and Methods 26 or 26A
applies to the analysis of gaseous hydrogen chloride.
Therefore, the commenter's suggested modification of
§63.1104(1) (1) (iii) is consistent with the EPA's intent and has
been adopted in the promulgated rule.
8.5.4 Low HAP Concentration Exclusion
Comment: One commenter (A-97-17, IV-D-01) stated that,the
low HAP concentration exclusion of §63.1104 (e) (2) (vi) limits
the ability of a source to qualify for a low HAP concentration
exclusion and requested that it be deleted. The commenter .(A-
97-17, IV-D-01) specified 3 reasons that disfavored a source
seeking to use the exclusion. The first reason was that TOC is
a broader class of HAP, and nonHAPs will be counted as HAPs.
The second reason was that including methane and ethane in the
TGC determination raises the TGC concen'cictLiOn mctkxiiy iL more
difficult to meet the applicability cutoff. The third reason
was that the "real" applicability concentration is not the
value listed in the applicability tables, but is 50 percent of
the listed value.
Response: The EPA agrees and has deleted this option in
the promulgated rule.
8.5.5 Process Changes
Comment: Two commenters (A-97-17, IV-G-04; A-97-17, IV-D-
01) requested that §63.1104(m) be edited to indicate that
8-29
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process changes are to be reported within 60 days of the
performance test or the applicability determination or in the
next Periodic Report, not in the Initial Compliance Status
Report (ICSR or Notification of Compliance Status (NOCS)). The
commenters explained that there is little value in reporting
changes made before the NOCS since compliance status is
established by the NOCS.
Response: The EPA agrees that it is unnecessary to report
process changes made before the Notification of Compliance
Status is submitted. Therefore, the promulgated rule has been
modified to indicate that process changes are to be reported •
within 60 days of a performance test or applicability
determination or in the next Periodic Report.
8.5.6 Opt-in Language
Comment: One commenter (A-97-17, IV-D-01) requested that
the EPA add appropriate wording to indicate that a source may
"opt-in" to the rule and not do "all of" testing if the
facility knows that their source is subject to control based on
process knowledge and demonstrates appropriate control the
affected stream. The commenter pointed to example opt-in
language in §63.1104 (a) where the source does not have to
calculate a TRE index value if the source is already sending
the vents to a flare or reducing the organic HAP by the
appropriate amount or to a TOC concentration limit.
Response: The EPA has included the language in
§63.1104 (a) stating that an owner or operator does not have to
calculate a TRE index value if the source is already routing
process vent emissions to a flare meeting the requirements
specified under 40 CFR part 63 subpart YY or reducing the
organic HAP or the TOC concentration limit by the amount
required under 40 CFR part 63 subpart YY. The EPA does not
want to require a source to do applicability testing and
calculations if their process knowledge is sufficient to
determine that they are subject to control. The EPA has
clarified in the promulgated rule that an owner or operator
8-30
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that opts to meet the most stringent control requirements of 40
CFR part 63 for their affected source emission point does not
have to do the required control assessment testing.
8.6 CROSS-REFERENCE, FORMAT AND GRAMMATICAL COMMENTS
The EPA received many editorial comments on the proposed
regulation. These comments primarily addressed typographical
errors, minor editorial corrections, editorial changes designed
to clarify provisions of the rule, and cross-referencing
errors. The EPA appreciates the effort made by commenters to
identify these errors and bring them to the EPA's attention,
and many changes have been made to the rule as a result of
these comments.
Extensive comments were also made on the applicability
tables associated with §63.1103. Due to printing errors, many
provisions in these tables did not appear correctly in the ;•
proposal, and required significant revision in the final rule.
Other comments had the intent of clarifying what were perceived
to be unclear provisions, or ensuring internal consistency of
provisions. These comments are discussed in greater detail •;
below.
Because of substantial changes made to subpart YY, many
comments received were no longer relevant. Specifically,
requirements for wastewater and batch unit operations were
deleted from the final regulation, as were requirements for
small storage vessels, and consequently, comments associated
with thpSP nrnwi ?; H rin c HiH'r>/->+- 3.™DlV
___ ^. — _. w ~ . v t_ t^.ff-i-jr.
Comment: One commenter (A-97-16, IV-D-01) stated that the
proposed rule inconsistently referred to "polycarbonate" or
"polycarbonates" production. In Table 1 of §63.1100, the term
"polycarbonate" is used, but many other references in subpart
YY are to "polycarbonates." The commenter requested that all
references in subpart YY be standardized to "polycarbonate"
production in order to avoid confusion.
Response: The EPA has revised the final rule to refer
consistently to "polycarbonate" rather than "polycarbonates."
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Comment: One commenter (A-97-17, IV-D-08) stated that
§63.1100(d) (4) (iii) should be revised to specify that
"information," rather than "material" be submitted to
demonstrate the appropriateness of parameter monitoring levels.
Response: In the final rule, §63.1100(d) (4) (iii) was
changed to §63.1100(d)(4)(ii)(C). The EPA made revised the
rule to use the word information rather than material in
§63.1100(d)(4)(ii)(C)(4.), as requested by the commenter, which
is consistent with the terminology used in
§63.1100(d) (4) (ii) (C) (1) .
Comment: One commenter (A-97-17, IV-D-08) recommended
that paragraphs 63.1100(e) and (f) be restructured to specify
that procedures shall be followed until storage vessel or
recovery operation equipment ownership is determined. The
suggested revised sentence is: "To determine the process unit
to which a storage vessel shall belong, the owner or operator
shall sequentially follow the procedures specified in
paragraphs (e)(l) through (e)(8) [or (f)(1) through (f)(7)] of
this section, stopping as soon as the determination is made."
Response: The EPA agrees with the commenter's suggestion
and has revised the regulation accordingly.
Comment: One commenter (A-97-17, IV-D-08) suggested that
§63.1100 (e) (8) (ii) be revised to refer specifically to the
"criteria of §63.1100 (e) (8) (i)," instead of to the
"requirements of this subpart." The commenter stated that this
clarified the provision in question, and conformed to a
parallel provision in §63.1100(e) (8) (iii) .
Response: The commenter is correct, and the final
regulation was revised to make this change.
Comment: One commenter (A-97-17, IV-D-08) stated that
§63.1100 (f) (3) should be revised to delete the phrase "located
on the same plant site as the recovery operation equipment"
because it is redundant and unnecessary language. The commenter
contended that this revision would make the provision
consistent with the parallel provision in §63.1100(f)(2).
8-32
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Response: The commenter is correct, and the regulation
was revised to make this change.
Comment: One commenter (A-97-17, IV-D-08) suggested
extensive revisions to §63.1100(g), modeling the recommended
changes on the proposed language in §63.1100(g)(4), which
refers simply to requirements "in this subpart," rather than
providing a more detailed reference to other regulations with
which subpart YY may overlap. Specifically, the commenter
stated that paragraphs (g)(1) through (3) should refer to the
storage vessel requirements, process vent requirements, and
transfer rack requirements, respectively, of this subpart,
instead of listing the detailed reference to subparts WW and
SS. The commenter contends that this is appropriate, because
subparts WW and SS are referenced in the storage vessel,
process vent, and transfer rack requirements of subpart YY, and
the proposed language is therefore unnecessarily redundant.
The commenter agrees that the specific references to subparts
TT and UU should be listed, as this allows Control Level 1 and
Control Level 2 requirements to be distinguished from each
other. Furthermore, the commenter stated that if compliance
with either subpart YY or the analogous requirements of the RON
cited in these paragraphs suffices for compliance with subpart
YY, then this should also suffice for compliance with the HON.
Other changes suggested by the commenter to these
paragraphs include replacing the word "provisions" with
"requirements" in §63.1100 (g) (1) through (g) (5), and replacing
"both rules" in §63.1100 (g) (5) with "both such requirements."
Other editorial changes were also recommended for these
paragraphs.
Response; The EPA agrees with the suggestion that the
simpler reference to the requirements of this subpart, rather
than a detailed reference to subpart WW or SS, is appropriate,
and the regulation was revised accordingly. However, the EPA
does not agree with the commenter's contention that compliance
with either the requirements of subpart YY or the analogous
8-33
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requirements of the RON should constitute compliance with both.
Instead, the regulation continues to say, as proposed, that
compliance with either constitutes compliance with subpart YY.
This is because it is not appropriate for subpart YY to
establish what constitutes compliance with the requirements of
the HON. The EPA also replaced the word "provisions" with
"requirements," as requested by the commenter.
Comment: One commenter (A-97-17, IV-D-08) noted that the
definition of "initial start-up" states that "initial startup
does not include "subsequent startup (as defined in this
section)." However, the commenter stated that since neither
startup nor subsequent startup are defined in this section, the
reference is confusing and requires clarification.
Response: The commenter is correct, and the EPA has added
definitions of "startup" and "subsequent startup" to the
regulation.
Comment: One commenter (A-97-17, IV-D-08) recommended
that the definition of "process unit" should be revised to
delete the list of equipment included in parentheses. The
commenter stated that since "equipment" is a defined term, it
is redundant to include this descriptive information in the
definition of process unit.
Response: The EPA agrees with the commenter and the
regulation has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-08) stated that the
definition of "process unit shutdown" should be revised for
clarity by adding the phrase "practice or procedure" as
follows: "...a work practice or operational procedure that
stops production from a process unit, or part of a process
unit, during which practice or procedure it is technically
feasible to clear process material from the process unit..."
Response: The EPA agrees with the commenter and the
regulation has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-08) recommended
that subparagraph (2) in the definition of "process unit
8-34
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shutdown" be revised to break the paragraph's two criteria into
two sections, identified as (A) and (B), as follows: "(2) An
unscheduled work practice or operational procedure that would
(A) stop production from a process unit, or part of a process
unit, for a shorter period of time than would be required to
clear the process unit, or part of the process unit, of
materials and start up the unit, and (B) result in greater
emissions than delaying repair of leaking components until the
next scheduled process unit shutdown."
Response: The EPA agrees with the commenter and the
regulation has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-08) suggested
revisions to the definition of "process wastewater" to clarify
the definition and to make it more consistent with the
definition in the HON. The suggested changes include the
addition of the phrase "wastewater stream," because, as the
commenter pointed out, it is used later in subpart YY
synonymously with process wastewater (§63.1100(g)(5)(i) and
(ii) and Table 5 to §63.1103, row 7). The commenter also
recommended that "wastewater" be changed to "water" to clarify
that wastewater is water first, not organics. Finally, the
commenter recommended that the phrase "and is to be discarded"
be added to clarify and emphasize that the water in question is
waste.
Response; The EPA is deferring action and soliciting
dcid-i-Lj-Onal CGiTuuent on the wastewatei provisions to be required
under the generic MACT rule. Therefore, this definition does
not appear in the generic MACT as of May 15,1999.
Comment: One commenter (A-97-17, IV-D-08) stated that
subparagraph (5) of the definition of "storage vessel or tank"
should be revised to use the term "vessels storing wastewater"
instead of "wastewater storage tanks." The commenter claimed
that this revision is consistent with the format of the
preceding subparagraphs, and also avoids using the term to be
defined in its definition.
i-35
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Response: The EPA agrees with the commenter and the
regulation has been revised accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that
"polycarbonate production area source" in §63.1102 (a) (2) (ii)
should be changed to "polycarbonate production minor source" in
order to more accurately describe the regulatory status of such
sources.
Response: The EPA does not agree with the commenter's
contention that the sources in question are better described as
"minor" instead of "area," which is the term for describing
sources that are not major sources under section 112 of the
Act. However, the EPA has changed the term "minor" to
"nonmajor" to meet the commenter's concern.
Comment: A commenter (A-97-19, IV-D-01) stated that in
Table 1 to §63.1103, row 3, in the "And if..." column, the
mathematical operator should be changed from "<." to "<". The
same commenter also stated that in row 6 of Table 1, in the "If
you own or operate..." column, the phrase should be revised to
read "a wastewater treatment system unit" in order to be
consistent with the defined term.
Response: The EPA agrees with the commenter's suggestion
with respect to the mathematical operator, and this change was
made to the regulation. The commenter's other suggested change
is no longer necessary or relevant, because wastewater
provisions were eliminated from the regulation.
Comment: A commenter (A-97-18, IV-D-01) stated that in'
Table 2 to §63.1103, row 4, in the "If you own or operate..."
column, the phrase should be revised to read "a wastewater
treatment system unit" in order to be consistent with the
defined term. The same commenter noted that in row 4 of Table
2, in the "And if..." column, "HAP" should be changed to
"acrylonitrile."
Response: Because wastewater provisions were deleted from
the regulation, the commenter's suggested changes were no
longer relevant.
8-36
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Comment: A commenter (A-97-16, IV-D-01) stated that
§§63.1103(d)(1)(i)(A) and (D) should be revised to specify
"organic HAP" instead of simply "HAP," in order to be
consistent with other provisions in the rule.
Response: The EPA agrees with the commenter's suggestion,
and the regulation has been revised accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, row 1, in the "If you own or operate..."
column should be revised to read "A storage vessel with: 8
cubic meters <. capacity < 75 cubic meters.
Response: The commenter's suggested change is not
relevant because requirements for existing storage vessels with
less than 75 cubic meters capacity were eliminated from the
final regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that-
Table 5 to §63.1103, row 1 (upper portion), in the "And if..."
column should be revised to read as follows: "41.3 kilopascals
< the maximum true vapor pressure of organic HAP < 76.6
kilopascals." The same commenter said that Table 5 to
§63.1103, row 1 (lower portion), in the "And if..." column
should be revised to read as follows: "27.6 kilopascals < the
maximum true vapor pressure of organic HAP < 76.6 kilopascals."
The commenter claimed that these changes are necessary in order
to ensure that these categories do not overlap with the
category in row 2, lower portion.
UU (JUiltiJ- UUilUlltill UB
subpart YY and as stated in a previous response, the EPA
eliminated requirements for existing small storage vessels from
the final regulation. This change resulted in different changes
from those suggested by the commenter's statement. In addition,
the 41.3 kilopascal cutoff no longer applies. Table 5 has,
however, been revised in the final rule to assure that the
applicability categories do not overlap inappropriately.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, row.2 (upper portion), in the "If you own
. 8-37
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or operate..." column should be revised as follows: "a storage
vessel with capacity > 151 cubic meters. The same commenter
believes that Table 5, row 2 (lower portion), in the "If you
own or operate..." column should be revised as follows: "a
storage vessel with capacity ^ 8 cubic meters." The commenter
claimed that this revision makes the comparison clearer.
Response: The "If you own or operate" column was revised
to indicate that it applies to storage vessels with a capacity
greater than or equal to 151 cubic meters. The second change
suggested by the commenter was not relevant because, in
response to another comment, requirements for small storage
vessels (i.e. <75 cubic meters for existing sources, and < 38
cubic meters for new sources) were deleted from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, row 3 (upper portion), in the "And if..."
column, the mathematical operator between TRE and 2.7 should be
<, instead of <, in order to be consistent with the "And if..."
column in row 4. The commenter pointed out that a TRE value
less than 2.7 requires control, whereas a TRE index value of
2.7 does not require control.
Response: As discussed above, because of broader changes
made to the requirements of the regulation, Table 5 was revised
considerably. The commenter's recommendations regarding
mathematical operators were incorporated where appropriate into
these revisions; however this specific comment was no longer
relevant.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, row 3 (upper portion), in the "Then you
.must..." column, the following text should be inserted after
the word "flare" in the upper requirement: "meeting the
requirements of 40 CFR subpart SS (national emission standards
for closed vent systems, control devices, recovery devices, and
routing to a fuel gas system or process) §63.987 of this part."
The commenter said that this change would conform to the format
of previous requirements in Table 5.
8-38
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Response: The EPA agrees with the commenter's suggestion
that the reference to subpart SS should be included
specifically in the table and has revised the rule accordingly.
However, changes in the specific control requirements have
resulted in changes to the specific cross-reference in subpart
SS that is relevant, so §63.987 is not referenced here.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, row 3 (upper portion), in the "Then you
must..." column, the final requirement, to "achieve and
maintain a TRE index value greater than 2.7," should be
deleted. The commenter states that if the TRE ^ 2.7, a row 4
applies.
Response: Again, as discussed in other responses to
comments, broader changes made to Table 5 and the control
requirements for polycarbonate sources mean that the
commenter's suggestion is no longer appropriate.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, row 3 (lower portion), in the "And if..."
column, the mathematical operator "<" should be inserted
between TRE and 2.7.
Response: Again, as discussed in other responses to
comments, broader changes made to Table 5 and the control
requirements for polycarbonate sources mean that the
commenter's suggestion is no longer appropriate. The
appropriate mathematical operator is less than or equal to. If
a source achieves and maintains a TRE above 2.7, no further
control is required.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, row 3 (lower portion), in the "Then you
must..." column should be revised to refer to "a process vent"
instead of "process vents" and to replace "by venting
emissions" with "then vent the control device." The commenter
said that these changes are consistent with other parts of the
table, and clearer.
J-39
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Response: The EPA agrees with the commenter, and the
regulation has been revised by incorporating the suggested
changes.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, row 4, in the "Then you must..." column,
should be revised to add a reference to the provisions of
§63.1104 (n), by adding the following text: "and, comply with
the provisions of §63.1104(n) of this subpart, as applicable."
The commenter claimed that this change clarifies the rule, and
the commenter also noted that while the proposed rule does not
have a §63.1104 (n), the commenter suggested in another comment
that §63.1104(m) (2) (iv) be renumbered as §63.1104 (n).
Response: . As discussed in other responses to comments,
broader changes made to Table 5 and the control requirements
for polycarbonate sources mean that the commenter's suggestion
is no longer appropriate.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, rows 5 and 6, the word "HAP" after "11,800
kilogram" should be deleted as it is redundant.
Response: Because requirements for batch unit operations
were eliminated from the final regulation, in response to
another comment received in subpart YY, the commenter's
suggestion is not relevant.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, row 6, in the "Then you must..." column
should be revised to specify "organic" HAP and to replace "by
venting emissions" with "then vent the control device."
Response: Because requirements for batch unit operations
were eliminated from the final regulation, in response to
another comment received in subpart YY, the commenter's
suggestion is not relevant.
Comment: One commenter (A-97-16, IV-D-01) stated that the
requirement in Table 5 to §63.1103, row 6, in the "Then you
must..." column is confusing as proposed. The commenter claimed
that it is not clear whether it is intended to be one
8-40
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requirement or two alternative requirements. The commenter
thought that, based on the context, on §63.1105, and on the
parallel provision in Table 6, row 5, that this provision
should be revised to clarify that two alternative requirements
exist, and to conform to the format in row 3. The commenter
suggested this could be achieved by deleting the phrase
"whichever is less stringent." The commenter further noted that
if the cited phrase is in fact integral to the meaning of the
requirement, then further clarification is necessary, as the
meaning is completely unclear.
Response: Because requirements for batch unit operations
were eliminated from the final regulation, the commenter's
suggestion is no longer relevant.
Comment: One commenter (A-97-16, IV-D-01) stated thatr-in
Table 5 to §63.1103, row 6, the "Then you must..." column, .
"process vents" should be replaced with "a process vent."
Response: Because requirements for batch unit operations
were eliminated from the final regulation, in response to
another comment received in subpart YY, the commenter's ;
suggestion is not relevant.
Comment: One commenter (A-97-16, IV-D-01) stated that-.;in
Table 5 to §63.1103, rows 7 and 8, in the "And if..." column,
the word "organic" should be inserted before "HAP, since
organic HAP is the regulated species.
Response: The EPA agrees with the commenter's suggestion
for ruw S, and has revised Lhe regulation accordingly. The
parallel change for row 7 is no longer applicable because
wastewater provisions were eliminated from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, footnote "b," the last sentence should be
revised to use the word "calculated" instead of "done."
Response: The EPA agrees with the commenter, and the rule
has been revised accordingly.
i-41
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Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, footnote "d, " "is" should be changed to
"are."
Response: The commenter's suggestion became irrelevant,
because this footnote was changed, since batch unit operation
requirements were eliminated from the final rule.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, footnote "e," should be revised to read as
follows: "The cutoff flow rate, average .flow rate, and annual
average flow rate are each determined according to the
procedures specified in §63.1105(d) and (e)."
Response: The commenter's suggestion became irrelevant,
because this footnote was changed, since batch unit operation
requirements were eliminated from the final rule.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 5 to §63.1103, footnote "f," should be revised to replace
"The determination of halogenated emissions from batch unit
operations" with "The aggregated mass emissions rate of halogen
atoms contained in organic compounds" in order to be more
clear.
Response: The commenter's suggestion became irrelevant,
because this footnote was changed, since batch unit operation
requirements were eliminated from the final rule.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 5 to §63.1103, footnote "i," "organic" should be inserted
before the word "HAP."
Response: The EPA agrees with the commenter's
recommendation, and the regulation has been revised
accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 1 in the "And if..." column should be
revised to read: "2.1 kilopascals $ the maximum true vapor
pressure of organic HAP < 76.6 kilopascals. The commenter
claimed that this change is necessary in order that this
8-42
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category does not overlap with the category in row 2, lower
portion.
Response: The commenter's recommended change is not
appropriate, because the EPA changed the vapor pressure
thresholds in the final rule.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 2 (upper portion), in the "If you own
or operate..." column, should be revised to read: "a storage
vessel with capacity > 151 cubic meters." The commenter
claimed that this revision makes the comparison clearer.
. Response: The EPA retained the order of comparisons as
proposed in order to be consistent throughout all of the rows
of each of the applicability tables.
Comment: One commenter (A-97-16, IV-D-01) stated that.
Table 6 to §63.1103, row 2 (upper portion), in the "And if..."
column should be revised to read: "the maximum true vapor
pressure of organic HAP z 5.2 kilopascals." The commenter
stated that this revision clarifies the provision.
Response; The EPA agrees with the commenter's
recommendation, and the regulation has been revised
accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 2 (upper portion), in the "If you own
or operate..." column, "a storage vessel with capacity z 38
cubic meters." The commenter claimed that this revision makes
the comparison clearer.
Response: The EPA retained the order of comparisons as
proposed in order to be consistent throughout all of the rows
of each of the applicability tables.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 2 (upper portion), in the "And if..."
column should be revised to read: "the maximum true vapor
pressure of organic HAP £ 76.6 kilopascals." The commenter
stated that this revision clarifies the provision.
5-43
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Response: The EPA agrees with the commenter's
recommendation, and the regulation has been revised
accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 3 (upper portion), the "And if..."
column, the mathematical operator between TRE and 9.6 should be
<, rather than <;, because if a new plant achieves a TRE index
value of 9.6, no control is required.
Response: The EPA does not agree with the commenter's
recommendation, and the regulation has not been revised as
suggested. Instead, if a TRE index above 9.6 is achieved and
maintained, no further control is required.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 3 (upper portion), the "Then you
must..." column, the following text should be inserted after
the word "flare" in the upper requirement: "meeting the
requirements of 40 CFR subpart SS (national emission standards
for closed vent systems, control devices, recovery devices, and
routing to a fuel gas system or process) §63.987 of this part."
The commenter said that this change would conform to the format
of previous requirements in Tables 5 and 6.
• Response: As with the similar comment on Table 5, the
EPA agrees with the commenter's suggestion that the reference
to subpart SS should be included specifically in the table and
has revised the rule accordingly. However, changes in the
specific control requirements have resulted-in changes to the
specific cross-reference in subpart SS that is relevant, so
§63.987 is not referenced here.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 3 (upper portion), the "Then you
must..." column, the requirement to "achieve and maintain a TRE
index value greater than 9.6" should be deleted, since if the
TRE index value is greater than 9.6, then no control is
necessary.
8-44
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Response: The EPA does not agree with the commenter's
recommendation, as the requirement to achieve and maintain a
TRE index value greater than 9.6 is an alternative to other
control requirements. However, if such a TRE index value is not
maintained, then other control requirements would apply.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 3 (lower portion), the "And if..."
column, the mathematical operator "<" should be inserted
between TRE and 9.6.
Response: The appropriate mathematical operator for the
row identified by the commenter is less than or equal to,
rather than simply less than, and the final rule reflects this.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 3 (lower portion), should be revised
to refer to "a process vent" instead of "process vents" and to-
replace "by venting emissions" with "then vent the control
device." The commenter said that these changes are consistent
with other parts of the table, and clearer.
Response: The EPA agrees with the commenter's
recommendation, and the regulation has been revised
accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 5, the word "HAP" after "11,800
kilogram" should be deleted as it is redundant.
Response: The commenter's recommended change is not
i.~e-Levant OeCaUSt; trie EPA ex i mi netted. i"eCjUii"erfientS j-Oi iJcitCfi unit
operations from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 5, in the "Then you must..." column,
should be revised to refer to "a process vent" instead of
"process vents" and to replace "by venting emissions" with
"then vent the control device." The commenter said that these
changes are consistent with other parts of the table, and
clearer.
8-45
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Response: The commenter's recommended change is not
relevant because the EPA eliminated requirements for batch unit
operations from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, row 5, in the "Then you must..." column,
should be revised to refer to "a process vent" instead of
"process vents."
Response: The commenter's recommended change is not
relevant because the EPA eliminated requirements for-batch unit
operations from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, there is no row number 6, and therefore
row number 7 should be renumbered as 6, and row 7 renumbered as
row 6. .
Response: The EPA has reserved and renumbered paragraphs
where appropriate to correct errors such as that mentioned by
the commenter, and to eliminate cross-referencing confusion.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 7 (should be 6), in the "If you own or
operate..." column, the phrase should be revised to read "a
wastewater treatment system unit" in order to be consistent
with the defined term.
Response: The commenter's recommended change is not
relevant because the EPA eliminated wastewater requirements
from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, row 7 (should be 6) and row 8 (should be
7), the .word "organic" should be inserted before the word
"HAP."
Response: The commenter's recommended change is not
relevant because the EPA eliminated wastewater requirements
from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, footnote "b," the word "done" should be
replaced with the word "calculated."
8-46
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Response: The EPA agrees with the commenter, and the
regulation was revised accordingly.
Comment: One commenter (A-97-16, IV-D-01) stated that in
Table 6 to §63.1103, footnote "e," should be revised to read as
follows: "The cutoff flow rate, average flow rate, and annual
average flow rate are each determined according to the
procedures specified in §63.1105(d) and (e)."
Response: The commenter's recommended change is not
relevant because the EPA eliminated requirements for batch unit
operations from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that
Table 6 to §63.1103, footnote "f," should be revised to replace
"The determination of halogenated emissions from batch unit
operations" with "The aggregated mass emissions rate of halogen
atoms contained in organic compounds" in order to be more
clear.
Response: The commenter's recommended change is not
relevant because the EPA eliminated requirements for process
vents from batch unit operations from the regulation.
Comment: One commenter (A-97-16, IV-D-01) stated that .-
Table 6 to §63.1103, references footnote "i," in row 8, but no
text for the footnote appears at the bottom of Table 6. The
commenter contended, therefore, that the text for this footnote
should be added, and that it should be identical to that of
footnote "i" in Table 5 to §63.1103.
Response: The commenter is correct, and. Luis footnote has
been added to Table 6. However, because of other changes made
to these tables, it is now footnote e.
Comment: One commenter (A-97-17, IV-D-08) claimed that
"(0.33 foot)" in §63.1104(b)(1) should be deleted because it is
confusing to include an English measure that could be
interpreted as a regulatory equivalent, despite §63.1108 (c).
For the same reason, the same commenter stated that "(0.99
pound per hour)" in §63.1104(b) (2) should be deleted.
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Response: The EPA does not agree with the commenter's
contention that more confusion than benefit results from the
inclusion of English units of measure in the regulation, and
therefore the commenter's suggested change has not been made.
The EPA believes that the inclusion of English units is helpful
to some owners and operators.
Comment: One commenter (A-97-17, IV-D-08) stated that
§63.1104(d)(1) should be revised to insert the following phrase
at the beginning of the paragraph: "For a process vent stream
that consists of at least one process vent from a batch process
manifolded with at least one process vent from a continuous
process (which combination is deemed a process vent from a
continuous unit operation as described in footnote "c" in
Tables 5 and 6)." The commenter claimed that this revision
clarifies that this provision is only applicable when a process
vent from a batch unit operation is manifolded with a process
vent from a continuous unit operation; otherwise, the standard
in §63.1104(c) applies.
Response: The EPA agrees with the commenter, and has
revised the rule accordingly, except for addition of
parenthetical phrase, as this is unnecessary.
Comment: One commenter (A-97-17, IV-D-08) stated that the
references in §63.1104(j) seem to have been inadvertently
omitted, and that this paragraph should refer to §63.1104(k)
and (1).
Response: The EPA agrees that the appropriate references
were inadvertently omitted. Cross-references to §63.1104(1) (1)
or (m)(2) were added to the regulation.
Comment: One commenter (A-97-17, IV-D-08) inguired why
the footnotes in Table 8, "AAAAMJ/scm" and "AAAASCM/min," have
the letter "A" repeated 4 times. The commenter assumed that
this was inadvertent, but requested clarification to be
certain.
Response: These were typographical errors which have been
corrected.
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Comment: -One commenter (A-97-17, IV-D-08) stated that the
abbreviation "scmm" is used in §63. 1104 (k), and that it should
first be defined as follows: "...with the 0.011 standard cubic
meters per minute (scmm) flow rate..."
Response : The EPA agrees with the commenter' s suggestion,
and the regulation has been revised accordingly.
Comment : One commenter (A-97-17, IV-D-08) noted that
§63. 1104 (m) (1) references paragraph (m) (3), but no such
paragraph exists. The commenter further stated that if this was
intended to refer to proposed §63. 1104 (m) (2) (iv) , the commenter
also recommended that this paragraph be renumbered to
§63.1104 (n) .
Response: The EPA has revised the regulation to cross-
reference (1) (1) through (1) (3) in §63 . 1104 (m) (1) .
Comment: One commenter (A-97-17, IV-D-08) stated that:
§63.1108 (b) (1) and (b) (2) should be revised to include a
reference to the description of excused excursions that appears
in §63.998 (b) (5) (ii) (E) .
Response : The EPA agrees with the commenter' s suggestion,
and the regulation has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-08) stated that the
phrase "a monitored parameter is outside its established range
or monitoring data cannot be collected" should be deleted from
§63. 1108 (b) (2) (i) , since it is redundant.
Response : The EPA agrees with the commenter' s suggestion,
and the regulation hss j^
Comment: One commenter (A-97-17, IV-D-08) stated that the
sentences in §63. 1108 (c) (4) that describe the use of English
units in the regulation should be deleted, because the
references to English units are confusing and unnecessary.
Response : As stated earlier, the EPA does not agree with
the commenter' s contention that more confusion than benefit
results from the inclusion of English units o.f measure in the
regulation, and therefore the commenter' s suggested change has
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not been made. The EPA believes that the inclusion of English
units is helpful to some owners and operators.
Comment: One commenter (A-97-17, IV-D-08) stated that
§63.1110 (b) (1) should be revised by adding the following
sentence at the end as a clarification: "This paragraph does
not apply to an affected source in existence on the effective
date of this rule.
Response: The EPA agrees with the commenter's suggestion,
and the regulation has been revised accordingly.
Comment: One commenter (A-97-17, IV-D-08) stated that
throughout the regulation, the phrase "calendar day" should be
replaced with "day," as "day" is defined in §63.1101 as a
calendar day.
Response: The EPA agrees with the commenter's suggestion,
and the regulation has been revised accordingly.
Comment: Two commenters (A-97-17, IV-G-04; A-97-17, IV-D-
01) identified a missing citation in the last sentence of
§63.1104 (e). This sentence, as proposed, follows:
record the TOC or HAP concentration as specified in
paragraph.
Response: The EPA has included the missing citation in
the last sentence of §63.1104(e) in the promulgated rule as
follows:
record the TOC or HAP concentration as specified in
paragraph (1)(3).
Comment: One commenter (A-97-17, IV-G-04) stated that
§63.1104 (e) (2) (i) needs the word "is" in the statement "in the
process vent."
Response: The EPA agrees with the commenter that the
inclusion of the word "is" is needed in §63.1104 (e) (2) (i) .
This section has been modified in the promulgated rule as
follows:
50% of total organic HAP or TOC, by volume, is in the
process vent.
Comment: One commenter (A-97-17, IV-G-04) stated that
because of the layout of §63.1104 (h) in the published proposal,
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it is not clear which equations are being referenced. The
commenter requested that wherever an equation is used to
fulfill a requirement of the rule, the equation number be
included as a reference.
Response: The EPA agrees with the commenter. Therefore,
the EPA has included equation reference numbers in the
promulgated rule whenever an equation is referenced.
Comment: One commenter (A-97-17, IV-G-04) stated the
proposed text in §63.1104 (j) is missing at least one citation.
This sentence, as proposed, follows:
...shall maintain records specified in paragraph (1)(1)
or (m)(2), as applicable.
Response: The EPA modified §63.1104(j) of the promulgated
rule by adding 2 references. The modified sentence follows:
...shall maintain records specified in paragraph (1)(1) or
(m) (2), as applicable.
Comment: Two commenters (A-97-17, IV-G-04; A-97-17, IV-D-
01) stated that §63.1104(m) refers to paragraph (m)(3). The
commenters (A-97-17, IV-G-04; A-97-17, IV-D-01) stated that
there was no paragraph (m)(3). The commenters (A-97-17, IV-G-
04; A-97-17, IV-D-01) requested that the reference to (m)(3) be
removed or replaced with the correct reference.
Response: Paragraph (m) specifies applicability
determination reporting requirements. The intended cross-
references were to specify that the applicability determination
recordkeeping requirements be reported in an owner or
operator's NOCS report. The EPA modified §63.1104(m) by
replacing the references to paragraph "(m)(2) or (m)(3)" with
"(1) (1) through (1) (3)," which cross-references the
applicability determination recordkeeping requirements that are
to be reported in the NOCS.
Comment: Two commenters (A-97-17, IV-G-04; A-97-17,
IV-D-01) stated that the reporting requirements of
§63.1104(m)(2)(iv) are not clear. One commenter (A-97-17, IV-
D-01) stated that the content of §63.1104(m)(2)(iv) appears
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unrelated and inconsistent with the rest of paragraph (m) and
suggested that it be a separate paragraph (i.e., paragraph
(n)). The commenter (A-97-17, IV-D-01) also contended that
§63.1104(m) (2) (iv) appears to require the use and monitoring of
pollution prevention measures for continuous process vents
whose TRE index value is maintained in the TRE index value
monitoring range without the use of a recovery device. The
commenter (A-97-17, IV-D-01) stated that the imposition of this
pollution prevention requirement represents a large extension
over existing law, and nowhere in part 63 is pollution
prevention required. The commenter (A-97-17,
IV-D-01) requested that §63.1104(m)(2)(iv) be modified.
Response: Upon assessment of §63.1104 (m) (2) (iv), the EPA
decided that §63.1104 (m) (2) (iv) was unnecessary and that the
pollution prevention requirements should be eliminated. The
intent of the proposed provisions was to define pollution
prevention within the context of the rule. However, since this
has led to greater confusion, the EPA has agreed with, and
adopted the commenter's (A-97-17, IV-D-01) requested
modifications and renumbering of §63.1104(m)(2)(iv) in the
final rule. The proposed §63.1104(m)(2)(iv) has been replaced
by the following paragraph in the promulgated rule:
(n) Parameter monitoring of certain process vents.
An owner or operator that maintains a TRE index value (if
applicable) in the applicable TRE index value monitoring
range as specified in an applicable table presented in
§63.1103 of this subpart without using a recovery device
shall report a description of the parameter(s) to be
monitored to ensure the process vent is operated in
conformance with its design or process and achieves and
maintains the TRE index value above the specified level,
and an explanation of the criteria used to select
parameter(s). An owner or operator that maintains a TRE
index value (if applicable) in the applicable TRE index
monitoring range as specified in an applicable table
presented in §63.1103 of this subpart by using a recovery
device shall comply with the requirements of §63.993(c) of
subpart SS.
8.7 COMPLIANCE WITH STANDARDS AND OPERATION AND MAINTENANCE
REQUIREMENTS
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8.7.1 Shutdown of Continuous Monitoring System
Comment: One commenter (A-97-17, IV-G-04) suggested that
the owner or operator of an affected source be allowed to re-
evaluate the shutdown of the continuous parameter monitoring
system (CPMS) after the event to determine if the shutdown was
necessary. The commenter explained that an owner or operator
would include a description of the event and the shutdown would
be added to the startup, shutdown, and malfunction plan (SSMP).
If it is determined that the shutdown was not necessary, the
incident would be described in the next Periodic Report.
The commenter explained that, as proposed, an owner or
operator is required to get approval from the Administrator to
shutdown a CPMS if they believe that a particular start-up,
shutdown, or malfunction would damage a CPMS. The following •
concerns were specified on the proposed rule:
• There is no procedure specified on how to obtain
approval or when such documentation is due.
• There is no indication that the Administrator will
respond within a reasonable time frame.
• It is almost impossible to predict which start-up,
shutdown, or malfunction will damage the CPMS.
• If a CPMS is damaged during a startup, shutdown, or
malfunction it may not be repaired soon enough to
demonstrate compliance after the event.
• If the CPMS is shut off during a startup, shutdown,
(jj. iiidirunCLxOii, j. L iiiciy Le used Lu uemuns LraLe
compliance after the event.but the owner or operator
will have violated this provision.
Response: The EPA has considered the commenter's concerns
regarding the proposed requirement under the generic MACT rule
for an owner or operator to get approval from the Administrator
to shutdown a CPMS if they believe that a particular start-up,
shutdown, or malfunction would damage a CPMS. Upon
consideration of the commenter's concerns, the EPA has deleted
the requirement for an owner or operator to get approval from
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the Administrator specifically to shutdown a CPMS from the
final rule. The 40 CFR part 63 subpart YY (the generic MACT
rule) start-up, shutdown, and malfunction plan provisions
parallel the intent and requirements of the part 63 General
Provisions which address the submittal and approval of, and
revisions to, the start-up, shutdown, and malfunction plan.
8.7.2 Excursion/Violation
Comment: One commenter (A-97-17, IV-D-01) stated that an
excursion that results from a not reasonably foreseeable
malfunction should not be considered a violation where the
owner takes reasonable steps to minimize excess emissions. The
commenter (A-97-17, IV-D-01) explained that, as proposed, if an
excursion occurs as a result of a process malfunction that is
not reasonably foreseeable and not in an owner or operator's
Startup, Shutdown, and Malfunction Plan, it would be a
violation.
Response: The EPA agrees with the commenter. Section
63.1108 (a) (1) and (b) (2) of the proposed rule indicates that
the standards and monitoring parameter ranges do not generally
apply during a malfunction. The EPA requires a program of
corrective action for malfunctions and describes procedures for
operating and maintaining the affected source at such times.
The EPA expects that corrective actions are taken during
unforeseeable malfunction events. The EPA does not view the
failure to foresee a specific malfunction as constituting a
violation as long as it meets the EPA's definition of a
"malfunction." To clarify the EPA's intent, a definition of
"malfunction" has been added to the final rule.
8.7.3 Credible Evidence
Comment: One commenter (A-97-17, IV-D-01) requested that
the EPA modify §63.1108(b). The commenter provided their
proposed revisions to the proposed §63.1108 (b) . The commenter
(A-97-17, IV-D-01) explained that, as proposed, §63.1108 (b) (1)
and (b)(5) allow the Administrator to establish noncompliance
with required operating conditions using information other than
8-54
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specified parameter monitoring data. The proposed language
suggests that an owner or operator cannot rely on continuous
monitoring data to demonstrate compliance.
The commenter (A-97-17, IV-D-01) also explained that
§63.1108 (b) (4) is either duplicative of, or inconsistent with,
emission point-specific applicability determination
requirements specified in 40 CFR Part 63 Subpart YY.
Section 63.1108 (b) (4) specifies generic applicability and
compliance assessments along with a caveat that determinations
do not need to be limited to what is specified. The commenter
(A-97-17, IV-D-01) explained that they were concerned about the
interaction of EPA's credible evidence regulations with
§63.1108 (b). Under the credible evidence regulations, the EPA
has asserted that it can use other information other than
information gathered during a performance test to show a
violation of numerical limits. The commenter (A-97-17, IV-D-
01) requested that the EPA state in §63.1108 (b) that the
conditions of the performance test are the conditions under
which compliance is to be determined and that there would need
to be a showing that any other data used to show noncompliance
be directly correlated to the conditions of a performance test.
Response: The EPA has not made the commenter's suggested
revisions. The suggested revisions are inappropriate because
they restrict the ability of the EPA to use other information
to determine compliance. The EPA may use any evidence that
indicates that the emission standard is not being met on B.
continuous basis, that parameter values are not being
maintained in the proper range, or that other requirements are
not being met.
8.8 RECORDKEEPING REQUIREMENTS
8.8.1 On-Site Data Retention
Comment: One commenter (A-97-17, IV-D-01) stated that
owners or operators of an affected source should not be
required to maintain more than six months of data onsite. The
commenter explained that inspectors rarely review more than the
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previous six months of data. The commenter stated that this
would be consistent with 40 CFR Part 63 Subpart F of the HON.
Response: The HON allowance was based on litigation and
should not apply to non-HON sources. The EPA has addressed
this issue under other rulemakings (i.e., the CAR). It was
agreed under the CAR that records of the most recent 2 years
must be retained on-site (or accessible to an inspector while
on-site), while the remaining 3 years may be kept off-site for
non-HON sources that use the CAR in the future. This agreement
was reached with substantial input from the EPA Regions, the
OAQPS, OECA, and the CMA.
8.8.2 Recordkeeping Summary Tables
Comment: One commenter (A-97-17, IV-G-04) requested that
the EPA prepare a set of tables (e.g., as in the HON) defining
all possible recordkeeping elements for the applicable rules.
As proposed, an owner or operator must search through the
equivalent of 5 subparts to find the information required to
demonstrate compliance and they might be subject to enforcement
if a piece of information is missed.
Response: The EPA agrees that a set of summary tables
outlining the recordkeeping requirements for the applicable
rules would be useful for an owner or operator trying to
discern their requirements. The EPA plans to prepare summary
tables outlining the recordkeeping requirements to assist
owners and operators of affected sources in discerning their
requirements. These tables will be made available on the EPA's
TTN web site.
8.8.3 Report Retention
Comment: One commenter (A-97-17, IV-G-04) contended that
requiring an owner or operator to retain copies of all
notifications, reports, etc., for 5 years is unwarranted
(§63.1109 (a)) . The commenter explained that the only reasons
why EPA would need an owner or operator to retain a copy of a
report that was submitted in full compliance with applicable
requirements would be "just in case" the EPA loses their copy,
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or that an inspector may want to review the facility's report
at the site. The commenter stated that an inspector could
review the reports before traveling to a site, or collect the
reports and bring them along for the inspection. The commenter
stated that these reasons would not be enough of a burden on
the EPA to justify requiring retention of a copy of every
report sent to the EPA, under the penalty of law.
Response: The EPA has not made the commenter's suggested
change. The information contained In reports submitted to the
EPA is important information for an inspector to have to
determine compliance. The EPA acknowledges that reports should
and are often reviewed and brought along by inspectors.
However, the EPA believes that an inspector should have all
records and reports that have been submitted to the EPA readily
accessible. One of the reasons for this is that the EPA may ;,.
decide they need to access a report that they did not bring as,
a result of their inspection.
8.9 REPORTING REQUIREMENTS
8.9.1 Notice of Initial Startup
. Comment: One commenter (A-97-17, IV-D-01) requested that'-
the EPA modify §63.11010 (b) to clearly indicate that only new - :
and reconstructed sources are required to submit a notice of
initial startup.
Response: The EPA agrees with the commenter's
clarification and has made the commenter's requested change in
'Cut: piOiiVulyctteCl rule .
8.9.2 Notification of Compliance Status
Comment: One commenter (A-97-17, IV-G-04) requested that
the EPA change all references to an Initial Compliance Status
Report (ICSR) to a Notification of Compliance Status (NOCS).
Response: The EPA agrees with the commenter that the EPA
should use consistent terminology; therefore, the promulgated
rule has been amended to change all references to an ICSR to a
NOCS.
8.9.3 Periodic Report
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Comment: One commenter (A-97-17, IV-D-01) stated that the
first Periodic Report be due 8 months after the Notification of
Compliance Status is due rather than 8 months after the source
becomes subject to 40 CFR Part 63 Subpart YY. As proposed, the
first several reports will not contain any information. The
commenter explained that their suggested change would be
consistent with the HON.
Response: The EPA agrees with the commenter that it does
not make sense to require submittal of Periodic Reports prior
to submittal of the Notification of Compliance Status report.
The promulgated rule has been modified so that the first
Periodic Report is due no later than 8 months after the
Notification of Compliance Status report is due and shall cover
the 6-month period beginning on the date the Notification of
Compliance Status is 'due.
8.9.4 Reporting Requirement Summary Tables
Comment: Two commenters (A-97-17, IV-G-04) requested that
the EPA prepare a set of tables (e.g., as in the HON) defining
all possible reporting elements for the applicable rules. As
proposed, an owner or operator must search through the •
equivalent of 5 subparts to find the information required to
demonstrate compliance and they might be subject to enforcement
if a piece of information is missed.
Response: The EPA agrees that a set of summary tables
outlining the reporting requirements for the applicable rules
would be useful for an owner or operator trying to discern
their requirements. The EPA plans to prepare summary tables
outlining the reporting requirements to assist owners and
operators of affected sources in discerning their requirements.
These tables will be made available on the EPA's TTN web site.
8.9.5 Implementation Schedule
Comment: One commenter (A-97-17, IV-G-04) stated that it
was not appropriate for the EPA to require that an owner or
operator submit a proposed implementation schedule under the
Initial Notification (§63.1110(c) (6)). The commenter explained
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that as much as 2 years or more of the 3 year period from the
promulgation date to the compliance date will be used making
these decisions. The commenter suggested that if the EPA
requires assurance that a facility will be in compliance on the
date required, the EPA may change this paragraph to indicate
that the source submit a statement that the source intends to
be in compliance by the compliance date.
Response: The EPA evaluated the commenter's comment and
agrees that it is unnecessary to require that an owner or
operator submit a proposed implementation schedule under the
Initial Notification. The requirements for an implementation
schedule was mistakenly adopted from the CAR where subject
sources are already complying with one of the underlying rules
consolidated under that rulemaking and has the option to comply
with the CAR. If the option of complying with the CAR is
executed, a compliance implementation schedule is required.
The EPA has deleted §63.1110(c)(6) from the promulgated rule.
8.9.6 Request for an Adjustment to Time Period or Postmark
Deadline
Comment: One commenter (A-97-17, IV-G-04) requested that
the §63.1110 (h) (6) provision that provides that the
Administrator notify the owner or operator in writing of
approval or disapproval of a request for an adjustment to a
time period or postmark deadline be modified to allow an owner
or operator to assume approval if a request does not receive
written disapproval within 15 days. The c Gaunt: ritei' explained
that approvals are often not made within the specified 15
calendar days and many requests go unanswered.
Response: As proposed, the generic MACT rule is
consistent with the part 63 General Provisions. The EPA
acknowledges that it is desirable for the Administrator to
approve or deny requests within the designated 15-day period.
However, it is important that changes in schedule be made based
on mutual agreement between the facilities and the States,
because both parties must change their respective schedules for
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handling the reports. Therefore, it is not appropriate to
grant a blanket approval for all requests that go unanswered in
that period of time. It is suggested that the facilities
consider their experience with typical turn-around times on
requests and factor that experience into their schedules when
submitting requests.
8.10 STARTUP, SHUTDOWN, AND MALFUNCTION
Comment: One commenter (A-97-17, IV-G-04) recommended
that the EPA remove the criteria under §63.1111(b)(1)(ii)(A)
and (B) (i.e., requires that periodic Startup, Shutdown, and
Malfunction (SSM) reports include the number of SSM events and
the total duration of all periods of SSM for the reporting
period). The commenter (A-97-17, IV-G-04) explained that
§63.1111 only requires reporting if the total duration of a
startup, shutdown, or malfunction exceeds specified durations
and the specified criteria in paragraphs (b)(1)(ii)(A) or (B)
of §63.1111 adds calculation burdens. The commenter
(A-97-17, IV-G-04) indicated that it is often easier to report
all SSM periods that caused excess emissions rather than
determining the percentage of time a Continuous Parameter
Monitoring System (CPMS) is not operating or malfunctioning, or
the percentage of time in which SSM events caused excess
emissions.
The commenter (A-97-17, IV-G-04) suggested that, if EPA
retains the provisions in § 63.1111 (b) (1) (ii) (A) and (B) of the
Generic MACT rule, the EPA should clarify the SSM information
that is to be included in the periodic SSM reports.
Specifically, the commenter (IV-G-01) requested that the EPA
clarify the following in the promulgated rule:
1. That a separate downtime percentage is required to be
calculated for each individual CPMS and that only SSM
event durations greater than 5 percent need to be
reported.
2. The periods of CPMS inoperation or malfunction that
should be included in the SSM report.
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3. Whether an owner or operator is required to include or
exclude periods of CPMS inoperation or malfunction when
the actions taken by an owner or operator are consistent
with procedures specified in the source's SSM plan. The
commenter requested that only the periods of CPMS SSM plan
be included.
4 . How to calculate the percentage of SSM time during
which excess emissions occur. The commenter (IV-G-01)
suggested that the EPA should require the percentage be
calculated on an emission point by emission point basis
considering the operating time of each emission point.
5. The periods of SSM that should be included in the
percentage calculation. The commenter (IV-G-01) suggested
that the EPA only require that the periods of SSM for
which actions are inconsistent with the SSM plan be
included in the percentage calculation.
Response : A semi-annual Summary Report of the occurrences
and durations of each SSM during which excess emissions occur
is required by the Generic MACT rule (40 CFR part 63 ;
subpart YY) . The EPA considers the semi-annual Summary Report
to be an important addition to the SSM provisions. The EPA -•
believes that the Summary Report would inform the EPA as to the
type and duration of SSMs.
Nevertheless, if the commenter believes that it is easier
to report all SSM periods of SSM and the total duration of
CCM
u V* a ,
is malfunctioning or not operating, or the percentage of
operating time in which SSM events occurred that caused excess
emissions, this is allowed. Therefore, the EPA has clarified
in the final rule that an owner or operator report may report
all SSM periods in lieu of calculating percentages. However,
the EPA does not believe that it is burdensome to calculate
these numbers. All an owner or operator needs is the total
duration of periods of SSM (for the reporting period) , the
total duration of CPMS operating time (for the reporting
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period), the total duration of periods of CPMS
nonoperation/malfunction, the total duration of period of SSM,
and the total operating time duration.
The EPA also agrees that clarification of the information
that must be included in the SSM Periodic Report would be
useful for an owner or operator responsible for preparing such
reports. Therefore, the EPA has specified what must be
included in the SSM Periodic Report in the promulgated rule.
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TECHNICAL REPORT DATA
(Please read Instructions on reverse before completing)
1. REPORT NO.
EPA453/C-9SKX)1
2.
4. TITLE AND SUBTITLE
National Errissicn Standards for Hizardcus Air Pdlutants (NESHAP)
Generic
MACT Background Information for Acetal Resins, Acrylic and Mxkaylic fiber,
Hydrogen Fluorids, and Polycarbonate Production Final Rule
7. AUTHOR(S)
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Emission Standards Division (Mafl Drop 13)
Office of Air Quality Planning and Standards
US. Environmental Protection Agency
Research Triangle Park, NC 27711
12. SPONSORING AGENCY NAME AND ADDRESS
Director
Office of Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSDN NO.
5. REPORT DATE
May 1999
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATDN REPORT NO.
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-D64008
13. TYPE OFREPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/200W
1 5. SUPPLEMENTARY NOTES
16. ABSTRACT
This dDcument contains a sunrrBry of public comments received en the N3SHAP for Acetal Resins, Acrylic and Mxlaoylic Rber,
Hydrogai Fluoride, and Polycarbomte Production Source Categories (40CFR 63, subparts SS, TT, UU, WW, and YY), which \\ere
proposed on October 14, 1998 (63 FR 55178). This document also provides the EPA's response to comments, and outlines the
charges made to theregulationin resporEe to public corrments.
17.
KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
Acetal Kesms ttooucuon, AoyncanaMoaaayncnrjernoauction,
Air Pdludon Control, Air Errissions Control, Qosed Vent Systems,
EnvironrrErtal Protection, Equipment Leaks, Hazardous Air
Pollutants, Hazardous Substances, Hydrogen Fluoride Production,
Polycarbonate Production, Process Vents, Reporting and
'Recordkeeping Requirements, Storage Vessels, Transfer Racks
18. DISTRIBUTION STATEMENT
Release Unlimited
b. IDENTIFIERS/OPEN ENDED TERMS
Hazardous air pouuianrs
19. SECURITY CLASS (Report)
Unclassified
20. SECURITY CLASS (Page)
Unclassified
c. COSATI
Field/Group
21. NO. OFPAGES
238
22. PRICE
EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION IS OBSOLETE
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