United States Office of Air Quality EPA-453/R-02-002

Environmental Protection Planning and Standards February 2002

Agency Research Triangle Park, NC 27711 http://www.epa.gov/ttn/atw/gp/gppg.html

National Emission Standards for

Hazardous Air Pollutants for Source

Categories: General Provisions and

Requirements for Control Technology

Determinations for Major Sources in

Accordance with Clean Air Act

Sections, Sections 112(g) and 112(j)-

Background Information for

Promulgated Standards

National Emission Standards for

Hazardous Air Pollutants for Source

Categories: General Provisions and

Requirements for Control Technology

Determinations for Major Sources in

Accordance with Clean Air Act

Sections, Sections 112(g) and 112(j)-

Background Information For

Promulgated Standards

EPA 453/R-02-002

Emissions Standards Division (ESD)

Office of Air Quality Planning and Standards

U. S. Environmental Protection Agency

Research Triangle Park, NC 27711

February 2002
This document has been reviewed by the Emissions Standards Division of the Office of

Air Quality Planning and Standards, U.S. Environmental Protection Agency (EPA), and

approved for publication. Mention of trade names or commercial products is not intended

to constitute endorsement or recommendation for use. Copies of this report are available

through the Library Services Office (C267-03), U.S. EPA, Research Triangle Park NC

27711, (919) 541-2777, or from National Technical Information Service, 5285 Port Royal

Road, Springfield VA 22161. You may also access this document on EPA’s website at

http://www.epa.gov/ttn/atw/gp/gppg.html.
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Table of Contents

Chapter 1- Introduction .............. .............. .............. . . 1

Chapter 2 - Comments and Responses on Part 63 General Provisions ...... 5

2.1 Overview .............. .............. .............. . . 5

2.2 General Comments on Subpart A .............. ........... 5

2.3 Comments on §63.1, Applicability .............. ........... 7

2.4 Comments on §63.2, Definitions .............. ........... 11

2.5 Comments on §63.3, Units and Abbreviations .............. 18

2.6 Comments on §63.4, Prohibited Activities and Circumvention

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

2.7 Comments on §63.5, Preconstruction Review and Notification

Requirements .............. .............. ........... 19

2.8 Comments on Startup, Shutdown, and Malfunction Provisions . 24

2.9 Other Comments on §63.6, Compliance with Standards and

Maintenance Requirements .............. .............. 33

2.10 Comments on §63.7, Performance Testing Requirements ..... 36

2.11 Comments on §63.8, Monitoring Requirements ............. 42

2.12 Comments on §63.9, Notification Requirements ............. 45

2.13 Comments on §63.10, Recordkeeping and Reporting

Requirements .............. .............. ........... 49

Chapter 3 - Comments and Responses on Section 112(j) ........... 52

3.1 Overview .............. .............. .............. . 52

3.2 General Comments on Section 112(j) .............. ....... 52

3.3 Comments on §63.50, Applicability .............. ......... 56

3.4 Comments on §63.51, Definitions .............. .......... 58

3.5 Comments on §63.52, Approval Process ............. 58

3.6 Comments on §63.53, Application Content for Case-by-Case

MACT Determinations .............. .............. ..... 67

3.7 Comments on §63.54, Preconstruction Review Procedures .... 68

3.8 Comments on §63.55, Case-by-case MACT Determinations ... 69

3.9 Comments on §63.56, Case-by-Case Determination After MACT

Promulgated .............. .............. ............ 69

3.10 Comments on 112(j) Guidance Document .............. ... 70

Chapter 4 - Other Comments .............. .............. .......... 75

4.1 Overview .............. .............. .............. . 75

4.2 Miscellaneous Comments .............. .............. . . 75
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Acronym List

BACT Best Available Control Technology

CAA Clean Air Act

CAR Consolidated Air Rule

CBI Confidential Business Information

CEMS Continuous Emission Monitoring System

CERCLA Comprehensive Environmental Response, Compensation, and

Liability Act

CFR Code of Federal Regulations

CMS Continuous Monitoring System

COMS Continuous Opacity Monitoring System

CPMS Continuous Parameter Monitoring System

EPA United States Environmental Protection Agency

FR Federal Register

HAP Hazardous Air Pollutant

HON Hazardous Organic NESHAP

LAER Lowest Achievable Emissions Rate

MACT Maximum Achievable Control Technology

NESHAP National Emission Standard for Hazardous Air Pollutants

NSPS New Source Performance Standards

OAQPS Office of Air Quality Planning and Standards

OECA Office of Enforcement and Compliance Assurance

OPPT Office of Prevention, Pesticides, and Toxic Substances

PSD Prevention of Significant Deterioration

SARA Superfund Amendments and Reauthorization Act

SIC Standard Industrial Classification

SIP State Implementation Plan

SSM Startup, Shutdown, and Malfunction

SSMP Startup, Shutdown, and Malfunction Plan

STAPPA/ALAPCO State and Territorial Air Pollution Program

Administrators/Association of Local Air Pollution Control

Officials

VOC Volatile Organic Compound
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Chapter 1- Introduction

On March 23, 2001, we proposed to amend the regulations in 40 CFR part 63,

subpart A, the General Provisions for National Emission Standards for Hazardous Air

Pollutants for Source Categories (66 FR 16318). In the same notice, we also proposed

amendments to 40 CFR part 63, subpart B, Requirements for Control Technology

Determinations in Accordance with Clean Air Act sections 112(g) and 112(j). These

amendments were proposed in part as a result of decisions reached in settlement

negotiations conducted between petitioners, who filed for review of the General

Provisions and the 112(j) rule, and the EPA. The proposed amendments also reflect

internal EPA discussions on issues regarding implementation of the General Provisions

and the 112(j) rule. 

The opportunity for written and oral public comment on the regulations was

announced with the proposal. No one requested to speak at a public hearing, therefore,

none was held. The period for written public comments on the proposed changes ended

on May 22, 2001. 

There were 27 comment letters (see Table 1) submitted by facility owners and

operators, trade associations, and State and local air pollution control agencies (IV-D-01

through IV-D-27). 

This document summarizes the written comments that were submitted in response

to the March 23 Federal Register Notice. These include comments on proposed

amendments to subparts A and B, as well as comments on the section 112(j) Guidelines

Document. This comment summary and our responses served as the basis for the

revisions made to the standards between proposal and promulgation. 
1- Introduction

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Table 1- Public Comments

Docket

Number

Commenter

IV-D-01 J.A. Hudspeth, P.E., Environmental Analyst IV, Environmental Services, Xcel Energy,

Amarillo, TX

IV-D-02 R.V. Vantuyl, Corporate Environmental Manager, Ash Grove Cement Company,

Overland Park, KS

IV-D-03 D.L. Arfmann, Attorney for the Colorado Association of Commerce and Industry (CACI),

Denver, CO

IV-D-04 R.H. Colby, Chair, ALAPCO Air Toxics Committee and B.L. Higgins, STAPPA Air

Toxics Committee, State and Territorial Air Pollution Program Administrators

(STAPPA)/Association of Local Air Pollution Control Officials (ALAPCO), Washington,

D.C.

IV-D-05 K. Garbin, Executive Director, National Coil Coating Association, Chicago, IL

IV-D-06 N. Dee, Ph.D., Director, Environmental Affairs, National Petrochemical & Refiners

Association (NPRA), Washington, D.C.

IV-D-07 D.C. Ailor, P.E., Director of Regulatory Affairs, National Oilseed Processors Association

(NOPA), Vegetable Oil MACT Coalition, Washington, D.C.

IV-D-08 R. Wood, Environmental Services, Health, Safety and Environment, Eastman Kodak

Company, Rochester, NY

IV-D-09 M.L. Fleischaker and D.M. Ottaviano, Arent Fox Kintner Plotkin & Kahn, P.L.L.C.,

Washington, D.C. counsel to the Motor and Equipment Manufacturers Association

(MEMA) and the Original Equipment Suppliers Association (OESA), Washington, D.C.

IV-D-10 L.S. Ritts, Counsel, National Environmental Development Association’s Clean Air

Regulatory Project (NEDA/CARP), Washington, D.C.

IV-D-11 K.B. Isakower, Chair, Coalition for Clean Air Implementation (CCAI)

IV-D-12 W.H. Lewis, Counsel, Morgan, Lewis & Bockius, L.L.P., Washington, D.C. representing

the Clean Air Implementation Project (CAIP)

IV-D-13 V. Ughetta, Director, Stationary Sources, Alliance of Automobile Manufacturers (AAM),

Washington, D.C.

IV-D-14 A.T. O’Hare, Vice President, Regulatory Affairs, American Portland Cement Alliance

(APCA), Washington, D.C.

IV-D-15 M.E. Keener, Ph.D., Executive Director, Coalition for Responsible Waste Incineration

(CRWI), Washington, D.C.

IV-D-16 W.F. Pedersen, Counsel, Composites Fabricators Association (CFA), Washington, D.C.
Docket

Number

Commenter

3

IV-D-17 M.H. Levin, Leonard Hurt Frost Lilly & Levin, P.C., Counsel, Can Manufacturers

Institute (CMI), Washington, D.C.

IV-D-18 R.B. Thompson, Manager, Air Toxics Section, Compliance Management Division,

Bureau of Air Quality, Department of Health and Environmental Control, State of South

Carolina, Columbia, SC

IV-D-19 L. Swaim, Regulatory Management Expertise Center, The Dow Chemical Company,

Freeport, TX

IV-D-20 B.L. Higgins, Assistant Secretary, Department of Environmental Quality, State of

Louisiana, Baton Rouge, LA

IV-D-21 M.G. Lusk, Director, Government Affairs, Cement Kiln Recycling Coalition (CKRC),

Washington, D.C.

IV-D-22 M.Y. Kinter, Vice president - Government Affairs, Screenprinting and Graphic Imaging

Association International and G. Jones, Manager, Environmental, Health and safety

Services, Graphic Arts Technical Foundation

IV-D-23 C.L. Phillips, P.E., Bureau of Air Regulation, Department of Environmental Protection,

State of Florida

IV-D-24 J. Sell, Senior Counsel, National Paint and Coatings Association (NPCA)

IV-D-25 M.A. McCord, Counsel, Morgan, Lewis & Bockius, L.L.P., Washington, D.C.

representing the American Chemistry Council

IV-D-26 Valerie Ughetta, Alliance of Automobile Manufacturers

IV-D-27 Michael McCord, Counsel, Morgan, Lewis & Bockius, L.L.P., Washington, D.C.,

representing the American Chemistry Council and the Clean Air Implementation Project

IV-D-28 Alison Keane, Counsel, National Paint & Coatings Association, Washington, D.C.

IV-D-29 James S. Pew, EarthJustice Legal Defense Fund, Washington, D.C.
4
2-GP Comments

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Chapter 2 - Comments and Responses on Part 63

General Provisions

2.1 Overview

The public comments on the proposed amendments to the General Provisions

concerned applicability, definitions, preconstruction review and notification, startup,

shutdown, and malfunction (SSM) provisions, compliance, performance testing,

monitoring, and notifications. These comments are summarized and responded to below.

2.2 General Comments on Subpart A 

2.2.1 Support Proposal

Comment:

Several commenters endorsed all of the proposed changes to 40 CFR part 63,

subpart A, the General Provisions. These commenters urged EPA to promulgate the

proposal with no substantial changes. They believed it would clarify obligations,

streamline procedures, provide greater certainty for sources and permitting authorities,

and reduce administrative burdens. (IV-D-06, 11, 12, 25) A few commenters generally

endorsed the proposal. (IV-D-02, 03, 10, 14, 17, 19, 22, 24)

Response:

We appreciate the support of these commenters.

2.2.2 Uniform Language

Comment:

One commenter stated that EPA sometimes uses traditional legal language in the

proposed amendments and sometimes uses plain language. The Agency should use one

or the other form consistently. (IV-D-19) Another commenter opposed the use of plain

language, believing it too difficult for the regulated community to interpret. (IV-D-01)

Response:

Plain language is used in the preamble, while the more traditional regulatory

language is used in the regulatory amendments. Because we are amending a regulation
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that was written prior to President Clinton’s June 1, 1998 executive memorandum on

plain language, we proposed the amendments in the traditional regulatory style for

consistency. Furthermore, since only regulatory language is used in the amendments,

commenter IV-D-01's concern about the use of plain language in the rule is not valid. 

Since issuance of the executive memorandum on plain language, which requires the use

of plain language in most government documents, we have incorporated plain language

wherever possible, such as in preambles. For the commenter’s concerns over the use of

the term “source” see comment 4.2.7 in this document.

2.2.3 Remove Universally Non-Applicable Requirements

Comment:

One commenter maintained that certain requirements in subpart A are consistently

removed from specific Maximum Achievable Control Technology (MACT) standards

because the MACT standards each have language that supersedes subpart A. The

commenter advocated that EPA remove these sections from the General Provisions. (IVD-19)

Response:

We do not agree with the commenter’s suggestion. The intent behind presumptive

applicability of the General Provisions is to avoid the repetition of common provisions in

each subpart, and this intention should be preserved, as discussed in the proposal

preamble at 16321/2. The regulatory development process for each NESHAP provides

the best mechanism for deciding which General Provisions are technically infeasible or

otherwise inappropriate. For example, many NESHAP regulate emissions of HAP that

are VOC, and in such cases, opacity requirements are moot and therefore overridden by

the individual standard. The proposed amendments clarify how to best communicate

these decisions, through the inclusion in each individual NESHAP of a table that

specifies whether requirements in the General Provisions are or are not applicable to the

rule in question. The commenter did not identify which provisions were “consistently

removed.”

2.2.4 Once In, Always In

Comment:

One commenter stated that the General Provisions should include language to

reflect agreements reached between EPA and the commenter regarding the effect of the

“once in, always in” policy on sources interested in reducing emissions through pollution

prevention. (IV-D-04)
2-GP Comments

7

Response:

We stated in Enclosure B, Response to STAPPA/ALAPCO Recommendations on

MACT/Title V Interface Issues, of our May 20, 1999 policy memo to Robert Hodanbosi

from John Seitz (http://www.epa.gov/ttn/oarpg/t5pgm.html), that “a workgroup

consisting of representatives from STAPPA/ALAPCO, OECA, OPPT, and OAQPS has

been established to address this issue. Our staff continues to work on this issue with the

workgroup. Once the workgroup has completed its efforts and has made a

recommendation, a decision will be made by EPA and sent to STAPPA/ALAPCO.” Any

amendments to this policy will be proposed in a separate action, and are not part of these

amendments.

2.3 Comments on §63.1, Applicability

2.3.1 More Stringent Emission Limitation [§63.1(a)(3)]

Comment:

One commenter preferred that EPA replace the last sentence in §63.1(a)(3) with

the following text: “. . .a facility need only comply with a single set of provisions of a

standard as determined by the Administrator.” The commenter stated that this approach

would clarify the source’s obligations and reduce the burden and confusion that could

result from having multiple standards apply to a source. (IV-D-19)

Response:

We agree with the commenter’s intent but do not believe the comment’s suggested

language is necessary. The proposed language clearly states that the Administrator may

do what the commenter suggests. Individual subparts will specify which emission

limitations and other requirements will apply and which will not. This will clarify

requirements for sources and reduce the burden of potentially duplicative requirements.

Comment:

One commenter believed that the phrase “more stringent” in §63.1(a)(3) is

ambiguous and open to interpretation. The commenter maintained that it is unclear

whether that clause may apply only to the applicability or emission control provisions in

the standard, or if it also applies to inspection, monitoring, recordkeeping and reporting

requirements. The commenter maintained that evaluating the stringency of all parts of a

standard for each emission point would be difficult, if not impossible. (IV-D-19)
2-GP Comments

8

Response:

The language referred to by the commenter was not proposed to be amended in

this action. We disagree with the commenter’s statement that evaluating the stringency

of all parts of a standard would be unduly difficult. Furthermore, monitoring,

recordkeeping, reporting, and inspection requirements are an integral part of any

regulation and must be considered in a stringency determination (for example, averaging

time affects the stringency of an emission limit).

Comment:

One commenter requested that EPA add language to §63.1(a)(3) to clarify that

when an affected source subject to a MACT standard no longer produces the primary

product, or changes the primary product so that it becomes subject to another standard,

the original MACT standard no longer applies to the source. In such cases, the

requirement in §63.1(a)(3) to meet the more stringent standard would not apply. (IV-D19)

Response:

The language referred to by the commenter was not proposed to be amended in

this action. We disagree with the commenter’s requested language change. The primary

product concept applies only in limited cases (for example, the Polyether Polyols

Production NESHAP), and it would not be appropriate to incorporate language

addressing this issue in the General Provisions. Individual NESHAP may address this

issue when appropriate.

2.3.2 NESHAP Identifies Applicable GP Requirements [§63.1(a)(4)(i)]

Comment:

One commenter supported EPA’s proposal that each NESHAP developed under

Clean Air Act (CAA) section112 (d) must identify the specific parts of the part 63

General Provisions that apply to sources subject to that NESHAP. (IV-D-19)

One commenter opposed §63.1(a)(4)(i), which they viewed as substantively

amending promulgated standards. The commenter stated that EPA cannot revise

Maximum Achievable Control Technology (MACT) standards that have already been

promulgated without reopening them and taking public comment. The commenter was

concerned that the proposed amendments would apply to the Vegetable Oil NESHAP (40

CFR part 63, subpart GGGG), which they did not want changed. They enumerated a
2-GP Comments

9

number of specific provisions in subpart GGGG, especially those relating to SSM, that

differed from those in the proposal. The commenter requested that EPA state in the

preamble to the final regulations that the SSM provisions do not apply to the Vegetable

Oil NESHAP. (IV-D-07)

Response:

We appreciate the support of commenter IV-D-19.

We agree with commenter IV-D-07’s assessment that certain startup, shutdown,

and malfunction provisions in the proposed amendments are inconsistent with the

promulgated Vegetable Oil NESHAP (see section 2.8.7) . We had previously reviewed

the existing rules and did not identify any substantive problems. However, the Vegetable

Oil NESHAP were promulgated after proposal of the General Provision amendments. 

We have discussed the implications with the commenter and as a result are editing

subpart GGGG to correct the inconsistencies.

We did not find, and the commenters did not note, any other instances in which

promulgated standards were substantively affected by §63.1(a)(4)(i). Therefore we are

promulgating §63.1(a)(4)(i) as proposed.

2.3.3 NESHAP Incorporates Other Requirements [§63.1(a)(4)(ii)]

Comment:

One commenter strongly supported proposed §63.1(a)(4)(ii). (IV-D-19) 

The commenter advocated that where a part 63 subpart supersedes the monitoring,

testing, recordkeeping, and reporting requirements of a part 60 subpart, the initial

notification requirements in §60.7(a)(1), (3), (4), and the reconstruction requirements in

§60.15(d) should not apply because these requirements would be overlapping, 

duplicative, and burdensome. The commenter maintained that it would be pointless to

notify EPA of construction or reconstruction commencing [§60.7(a)(1)], the actual date of

initial startup [§60.7(a)(3)], a physical or operational change [§60.7(a)(4)], or

reconstruction [§60.15(d)] when the Agency would be receiving such information in the

reports required under part 63. Any new process units or new emission points added to

an existing affected source would be included in a periodic report or in the application for

approval of construction or reconstruction.

The commenter also stated that EPA should provide general guidelines on how to

implement the standards when a part 63 standard incorporates a part 60, 61, or 63

standard, and there is contradicting, unclear, or absent information. The commenter 
2- GP Comments

10

requested clarification on how several specific provisions under the vinyl chloride

NESHAP in part 61 would apply to their source, which is subject to the HON in part 63,

subparts F and H. The commenter also asked several specific questions about

implementing §63.523(c) of subpart W (National Emission Standards for Hazardous Air

Pollutants for Epoxy Resins Production and Non-nylon Polyamides Production), which

says that owners or operators of existing, new, or reconstructed affected basic liquid resin

lines must comply with the HON subpart H requirements for equipment leaks. The

commenter explained that there are minor differences between the definition of

equipment leaks in subpart W at §63.522 and the definition of equipment in §63.161. 

(There is no definition of equipment leaks in the HON.) 

Response:

We agree with the commenter that where a part 63 standard overlaps another

standard, the part 63 standard must be clear which provisions apply or don’t apply in the

other standard. For this reason, we proposed to revise §63.1(a)(4)(ii). Subsequent

NESHAP should incorporate this concept and should be clear which provisions of

overlapping standards apply or don’t apply . The public, including facilities that may be

affected by the proposed NESHAP, is encouraged to identify any contradicting, unclear,

or absent information for any part 63 standards proposed in the future during the public

comment period so that any such issues may be resolved before promulgation.

We agree generally with the commenter that multiple notification and reporting

requirements for the same emission unit under different standards is burdensome and

undesirable. For part 63 standards that have already been promulgated, as well as other

applicable requirements under parts 60 and 61, we have articulated our policy on

streamlining multiple requirements that apply to a single emission unit in the March 5,

1996 policy memo, “White Paper Number 2 for Improved Implementation of the Part 70

Operating Permits Program,” which you may find at

http://www.epa.gov/ttn/oarpg/t5wp.html. This memo provides general guidelines on how

to implement standards when there are duplicative or overlapping requirements as

follows:

“... Multiple emissions limits may be streamlined into one limit if that limit is at

least as stringent as the most stringent limit. If no one requirement is unambiguously

more stringent than the others, the applicant may synthesize the conditions of all the

applicable requirements into a single new permit term that will assure compliance with

all requirements. The streamlined monitoring, recordkeeping, and reporting

requirements would generally be those associated with the most stringent emissions limit,

providing they would assure compliance to the same extent as any subsumed monitoring. 

Thus, monitoring, recordkeeping, or reporting to determine compliance with subsumed

limits would not be required where the source implements the streamlined approach.” 
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The White Paper 2 also discusses in detail the procedures for permitting authority

and source owner/operator involvement in developing, issuing, and implementing a title

V permit containing streamlined permit terms and conditions. 

2.3.4 Applicability Determinations For Source Category Only

[§63.1(b)(3)]

Comment:

Two commenters supported the proposed changes to §63.1(b)(3) that would

require a record of applicability determinations only for sources within the source

category that the relevant standard regulates. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.4 Comments on §63.2, Definitions

2.4.1 Affected Source

Comment:

A few commenters supported the definition of affected source, believing it would

clarify the applicability of each NESHAP. (IV-D-12, 25).

A few commenters believed EPA still needed to clarify in the definition of affected

source that sources that do not emit HAP are not part of the affected source. For

example, transfer points and other manufacturing elements at a facility are totally

enclosed, don’t emit HAP, and should not be included in the affected source. 

(IV-D-02, 14)

Response:

We appreciate the support of commenters IV-D-12 and 25. We disagree with the

suggestion by commenters IV-D-02 and 14 that the definition of “affected source”

requires further revision. The issue about sources that do not emit HAP will be

addressed, if appropriate, in each NESHAP, which must clearly define the affected

source. Each NESHAP should make clear what parts of the facility have reporting,

recordkeeping, monitoring, or other compliance requirements. Not all of the processes in

the affected source will necessarily have requirements; however, it may not always be
2- GP Comments

12

technically feasible or practical to separate sources that do not emit HAP from the

affected source.

2.4.2 Construction 

Comment:

A few commenters supported EPA’s proposed definition of construction, stating

that sources should be allowed to move existing equipment without triggering new source

requirements. (IV-D-16)

Two commenters believed relocated sources should be subject to standards for new

sources. (IV-D-04, 23) One of the commenters stated that if a source owner/operator

knows that equipment will be relocated, they don’t have to plan how to accommodate it. 

Therefore, they don’t need the longer time that existing sources have before complying

with the NESHAP. (IV-D-23) The other commenter noted that the only time that EPA

has issued a policy statement that relocated sources were not new sources was in the dry

cleaning MACT, where consolidation of machines at other locations would not constitute

a new source.) This commenter requested that EPA clarify this issue in the rule by

treating relocation as a new source. (IV-D-04)

Another commenter preferred that EPA either delete the word “all” from the

definition of construction or reword the definition, explaining that in some instances it

wouldn’t make sense to relocate every single piece of equipment in the affected source. 

For example, an owner/operator might choose to eliminate a spare storage tank and the

piping that runs to it. Since they would not be removing and reinstalling “all” of the

equipment, they may not meet the definition of construction. (IV-D-19)

Response:

We disagree with the commenters who stated that relocation means a source

should be treated as a new source. An existing source that relocates and makes no other

changes is still an existing source. Changes to the source means changes to the source’s

process or control equipment, method of operation, or emissions. This is clear in the

Part 60 rules at 60.14(e)(6) and the same logic applies here. This was also further

clarified in section 2.3.1 of “General Provisions for 40 CFR Part 63; Background

Information Document for Promulgated Regulations,” EPA-450-3-91-019b, February

1994:

“...affected sources for which construction or reconstruction is commenced before

the proposal date would be considered existing sources subject to MACT for

existing sources, and affected sources for which construction or reconstruction is
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13

commenced after the proposal date would be considered new sources subject to

MACT for new sources. If a new or existing source subsequently is relocated, and

if no other changes are made to the source (other than a change of ownership) as a

result of the relocation or in the process of relocation, that source generally would

continue to be subject ot the same emission standard requirements that it was

subject to under th relevant standard before the relocation took place.”

The source would be subject to new source requirements if, in the process of relocating,

the source was reconstructed, that is there was significant replacement of components

according to the definition of reconstructed.

Our intent in revising the definition of construction is to allow existing sources

that may need to move for various reasons (losing a lease, change in ownership, etc.) to

do so without being subject to standards for new sources. We originally anticipated that

this might apply to smaller, discrete emission units such as tanks for electroplating or

other uses. However, as the commenters have pointed out, in some cases there may be a

need to move a more complex affected source comprising a process unit or units,

including various pieces of minor ancillary equipment. 

Our intent in including the word “all” in the definition of construction in proposed

§63.2 was to ensure that an owner/operator could not “fragment” the affected source

such that the standards no longer applied. We believe it is reasonable for an

owner/operator to move an existing affected source and to reinstall the existing affected

source at another location without being subject to new source standards, as long as the

existing source is not changed such that it is reconstructed as defined in §63.2. We agree

with the commenters that in some instances it would not make sense to relocate every

single piece of equipment in the affected source. When an existing affected source is

relocated, the owner/operator should be able to replace minor ancillary equipment in the

affected source, such as piping, ductwork, valves, and wiring for monitoring systems,

without triggering the standards for new sources. However, the costs of reinstalling such

new minor ancillary equipment must be considered in determining whether the source

has been reconstructed. If the costs of reinstalling minor ancillary equipment meet the

definition of reconstruction as defined in §63.2, the existing affected source that is

relocated is reconstructed and subject to the standards for new sources. Determination

of whether an existing affected source that is relocated has been reconstructed must be

made by the permitting authority on a case-by-case basis.

We also note that relocation does not mean that the source gets three years to

come into compliance at the new location. If an existing source is relocated after the

compliance date has passed, it is an existing source and must remain in compliance.
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14

We have revised the definition of construction in §63.2 to allow the replacement of 

minor ancillary equipment in the affected source, as long as the cost of reinstalling the

minor ancillary equipment does not constitute a reconstruction. We have retained the

word “all” in the definition, as otherwise it would be unclear if the relocation exemption

applies to a situation where portions of several defunct plants were used to create a new

plant.

2.4.3 Compliance Plan

Comment:

Two commenters supported deleting the definition of compliance plan. 

(IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.4.4 Federally Enforceable

Comment:

One commenter requested that EPA delete “adequate” from paragraph (6)(v) of the

definition of federally enforceable. The commenter maintained that adding the word

adequate introduces an ambiguity into the rule that could subject many such requirements

to legal challenge. (IV-D-10)

Response:

There was no substantive change made to the definition of “federally

enforceable.” In the General Provisions promulgated on March 16, 1994 at 15 FR

12430, paragraph (b)(6) of the definition of “federally enforceable” referenced the

provisions for federal enforceability of requirements under the State Implementation Plan

(SIP). These criteria were published in the Federal Register on June 28, 1989 at 54 FR

27274. In the proposed amendments, these criteria were incorporated verbatim into the

definition. Therefore, we disagree with the commenter’s suggestion.
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2.4.5 Major Source

Comment:

One commenter appreciated EPA’s discussion in the preamble of the effect of a

public right of way on the definition of major source. (See 66 FR 16324-5.) The

commenter requested that EPA change the definition of major source in the rule such that

only facilities that are physically next to each other, or would be next to each other but for

an intervening public right of way, are contiguous for purposes of regulations under

section 112. The commenter maintained that both the statutory language and the

legislative intent confirm this meaning. The commenter pointed out that often fabricators

cannot expand at the same location and have therefore constructed new facilities. Their

experience is that regulators have attempted to interpret facilities that were not next to

each other, but were “close enough” in the judgment of the regulators, as contiguous. 

This view led to disputes and uncertainty. (IV-D-16)

Another commenter, however, requested that EPA revise the definition of major

source by replacing “located within a contiguous area with “located on one or more

contiguous or adjacent properties.” The commenter noted that EPA policy is that two

pieces of property do not have to be touching to be adjacent, they can just be near or close

by. The commenter also recommended that EPA add language clarifying that properties

do not actually have to be touching to be contiguous. (IV-D-23)

Response:

As commenter IV-D-16 noted, we discussed the definition of “major source” and

the possible effects of a public right of way on the determination of whether facilities

constitute a major source in the preamble at 16324-5. Because it is impossible to

anticipate all possible situations that may occur regarding major source determinations

and contiguous facilities, these decisions must be made by the permitting authority on a

case-by-case basis. For this reason, it is not necessary or appropriate to amend the

“major source” definition as the commenter suggests.

We also disagree with commenter IV-D-23's suggestion to add the word

“adjacent” to the definition of “major source” and to clarify that properties do not have

to be touching to be contiguous. “Adjacent” is a regulatory concept that applies to part

51, not part 63. New Source Review and MACT programs have different objectives;

therefore it is reasonable that these definitions are distinct. Furthermore, as we noted

above, the meaning of contiguous was discussed in the preamble. Further modifications

to the definition are not necessary.
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2.4.6 Malfunction

Comment:

Two commenters requested that EPA clarify the terms “sudden,” “infrequent,” and

“not reasonably predictable” in the definition of malfunction. Otherwise, the definition of

malfunction could be so broadly interpreted that there would never be a violation.

(IV-D-04, 18)

Response:

The terms “sudden,” “infrequent,” and “not reasonably preventable” (not

“predictable”) are included in the General Provisions as promulgated on March 16,

1994 at 15 FR 12430. They were not part of the litigation discussions or decisions, and

were not proposed to be amended. We appreciate the commenters’ concern that

malfunctions must be appropriately defined in the SSMP to avoid circumvention of the

regulatory requirements. The permitting authority will make case-by-case

determinations where necessary, and owners or operators can discuss the meaning of

these terms with the permitting agency if necessary. Individual rules may choose to

provide examples of SSM, or what would not be considered SSM for the specific source

category. The rule is not being changed as the commenters requested.

2.4.7 Monitoring

Comment:

One commenter suggested that EPA add the words “or to verify a work practice

standard” be inserted after the word device in the definition of monitoring. This change

would cover monitoring for work practice standards. (IV-D-03).

Response:

We agree that definition of monitoring should be revised to ensure that our intent

of including monitoring for work practice standards is clear. We have, therefore, revised

the definition to include the suggested phrase as well as included several additonal

clarifying examples in the text of the definition.
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2.4.8 New Affected Source

Comment:

A few commenters supported adding a definition for new affected source,

believing it would clarify when the new source MACT standards apply. These

commenters advocated the logic and the specific criteria that EPA identified for

determining when the new affected source would be different from the affected source. 

(IV-D-12, 17, 25).

Response:

We appreciate the commenters’ support.

2.4.9 Part 70 Permit

Comment:

Two commenters supported deleting the definition of “part 70 permit.” 

(IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.4.10 Reconstruction

Comment:

One commenter supported adding the phrase “unless otherwise defined in a

relevant standard” to the definition of “reconstruction.” The commenter further stated

that EPA should establish guidelines for evaluating technical and economic feasibility in

determining the fixed capital cost basis for reconstruction. The commenter recommended

that EPA clarify that, at a minimum, reconstruction is the replacement of at least 50% of

the fixed capital cost of a source. (IV-D-19).

Response:

We appreciate the commenter’s support. We did not propose to further amend this

definition, and will not be promulgating a change.
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2.5 Comments on §63.3, Units and Abbreviations

2.5.1 Corrections

Comment:

One commenter provided corrections for the symbols for microgram and microliter

and suggested adding an abbreviation for cubic meters at standard conditions per minute.

(IV-D-19)

Response:

We appreciate the commenter’s corrections and have made the recommended

changes.

2.6 Comments on §63.4, Prohibited Activities and

Circumvention 

2.6.1 Fragmentation

Comment:

Two commenters requested that EPA identify in the regulation a specific period of

time over which replacing components would be considered upgrading a project rather

than fragmenting it. The commenter noted EPA’s statement in the preamble in the

middle column of 16325 that “However, if the same process unit were expanded,

debottlenecked, or upgraded over time by replacing these various components, the

projects should not be considered together to determine whether the 50 percent of fixed

capital cost is eventually exceeded since the projects were not phased (or fragmented) to

avoid new source MACT. The commenter also requested that the Agency provide

criteria for determining when a facility may be intentionally circumventing MACT

requirements by phasing in a project. (IV-D-04, 18)

Response:

The determination of whether fragmentation (or deliberate circumvention) has

occurred must be made by the permitting authority on a case-by-case basis, because the

specific criteria will vary depending upon the sources involved, and it is not reasonable

or possible to establish criteria for this determination that will adequately address all

circumstances. For this reason, we decline to specify a period or specific criteria as the
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commenters requested. Individual rules may provide specific timeframes or additional

criteria if appropriate.

2.7 Comments on §63.5, Preconstruction Review and

Notification Requirements

2.7.1 Use of Term Nonmajor Emitters

Comment:

One commenter opposed EPA’s use of the term nonmajor emitters in §63.5(a)(2)

and other paragraphs. The commenter preferred that EPA use the term area source. If

EPA does not use the term area source, then the Agency should define nonmajor emitters

in §63.2. (IV-D-19)

Response:

A nonmajor emitter in this context is not the same as an area source. The term

“nonmajor emitters” refers only to affected sources (the collection of equipment and

emission points subject to the standard) that do not have the potential to emit,

considering controls, in the aggregate 10 tons per year or more of any hazardous air

pollutant or 25 tons per year or more of any hazardous air pollutants. Area and major

sources are determined by the HAP emissions from all emission points at the plant site,

not just the affected source, which is sometimes only a small part of the overall source. 

However, there are some instances in the preamble and in the proposed

regulations where we inadvertently omitted the term “affected source” when discussing

nonmajor emitters. This omission may have created confusion regarding nonmajor

emitters. Therefore, we have revised the regulations at §63.5(a) and (b) to clarify that we

are referring to nonmajor-emitting affected sources. 

2.7.2 Preconstruction Review Requirements [§63.5(a)(1)]

Comment: 

One of the commenters stated that section 112(i)(1) as written would require

preconstruction review for new sources affected by a MACT standard, regardless of

whether the source starts up before or after the effective date of the MACT standard. The

commenter maintained that this establishes unnecessary administrative burdens, because

the source must comply with MACT in either case. The commenter recommended a

“postcard notice” instead for these cases. (IV-D-24).
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Response:

Section 63.5(a)(1) of the General Provisions implements section 112(i)(1) of the

Act. We do not have the authority to alteror override the statutory provisions. The

proposed preconstruction review and approval requirements apply to new affected

sources or reconstructed sources that start up after the effective date of a relevant

standard.

2.7.3 Construction and Reconstruction Requirements [§63.5(b)]

Comment: 

One commenter stated that the proposed amendments would require full

preconstruction review for any “major-emitting” unit or process within an affected

source, even when the unit is not within any listed source category. The commenter

disagreed with this approach and maintained that sources within categories or

subcategories that have not been listed under section 112(c) should not be subject to

preconstruction MACT determinations under section 112(g). (IV-D-24)

Response:

The meaning of the comment is not clear to us. Preconstruction review under

§63.5 applies only to new or reconstructed affected sources. By definition, affected

sources are subject to standards developed under section 112 and thus are part of the

listed source categories. The commenter did not provide adequate information regarding

the provisions that were of concern, and thus we are unable to adequately respond. The

commenter appears to be concerned with section 112(g) provisions, rather than the

General Provisions or section 112(j) and as such is not within the scope of these

amendments. 

Comment: 

One commenter suggested that EPA reorder the phrase at the end of §63.5(b)(3),

“without obtaining written approval in advance, from the Administrator in accordance

with the procedures specified in paragraphs (d) and (e) of this section.” The commenter

recommended moving this phrase in front of the colon, before §63.5(b)(3)(i), so that it is

clear that the phrase applies to §63.5(b)(3)(i) and (ii). (IV-D-03)

Response:

We agree with the commenter and have revised the rule accordingly.
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2.7.4 Notification of Construction or Reconstruction for Nonmajor

Emitters [§63.5(b)(4)]

Comment: 

Several commenters recommended deleting the requirement that nonmajor emitters

submit a notification of construction or reconstruction. (IV-D-02, 14, 19, 24) 

Response:

We disagree with the commenters’ recommendation that the notification of

construction or reconstruction requirement be eliminated. This notification is not

particularly burdensome to a source; yet it is important for the permitting authority to be

aware of this information. The rule has not been changed in this regard.

2.7.5 Compliance Extension Requirements [§63.5(b)(5)]

Comment: 

Two commenters supported the proposal to reserve §63.5(b)(5) concerning

compliance extensions, as these requirements are covered elsewhere in the rule. (IV-D02, 14)

Response:

We appreciate the commenters’ support.

2.7.6 Adding Equipment and Making Process Changes [§63.5(b)(6)]

Comment: 

One commenter requested that EPA clarify in §63.5(b)(6) that adding new

equipment or making a process change does not trigger new source requirements. (IV-D19) Another commenter suggested that EPA revise the proposed language by replacing

the phrase “considered part of the affected source” with “ considered part of the existing

affected source.” The commenter maintained that this change would clarify that

something less than reconstruction will not subject the affected source to new source

MACT. (IV-D-03)
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Response:

Individual NESHAP will define what constitutes a new or reconstructed affected

source for the purpose of such determinations. It is not appropriate to revise the rule as

the commenter suggests, because the provisions in §63.5(b)(6) apply to both new and

existing sources. If equipment is added to an existing affected source, that equipment

becomes part of the existing affected source if such equipment is part of the affected

source definition. Similarly, if equipment is added to a new affected source, that

equipment becomes part of the new affected source. The determination of whether

reconstruction has occurred is separate from the provisions in this paragraph.

2.7.7 Commence Construction

Comment:

A few commenters expressed support for EPA’s amendments to §63.5(d)(1) of the

General Provisions to specify the beginning, rather than commencement, of construction

where appropriate. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.7.8 Information in Construction or Reconstruction Application

[§63.5(d)(2)]

Comment: 

One commenter preferred that general expressions (for example, organic HAP

from combustion of distillate fuels) be used in the approval of construction form in

§63.5(d)(2), rather than listing each type of hazardous air pollutant emitted. (IV-D-03)

Response:

Section 63.5(d)(2) lists the requirements for the application for approval of

construction. This paragraph states “Each application for approval of construction shall

include...technical information...including an identification of each type of emission point

for each type of hazardous air pollutant that is emitted...” We believe that this language

adequately addresses the commenter’s request, as the phrase “each type of hazardous air

pollutant” does not require that each specific HAP be itemized, but rather it permits

broader categorization of the HAP that are emitted.
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2.7.9 Substantially Equivalent Preconstruction Review [§63.5(f)(1)]

Comment:

One commenter supported the concept in §63.5(f)(1) that construction and

reconstruction approval for MACT standards can occur under State preconstruction

review programs. (IV-D-03) 

A few commenters disagreed with the provisions in proposed §63.5(f)(1)(i) and

(ii), which they interpreted as requiring each owner/operator to demonstrate that the State

or local agency review is substantially equivalent to the relevant requirements in §63.5. 

The commenters instead believed that EPA should determine which State or local air

permit programs have substantially equivalent preconstruction review requirements. (IVD-03, 19) One of the commenters noted that if EPA has delegated authority to a State or

local agency to implement subpart A of part 63 and part 70, then EPA has already agreed

that the preconstruction review and approval process is substantially equivalent to the

federal requirements. (IV-D-19) Another commenter said that the construction and

reconstruction approval requirements in §63.5(e) would ensure that the permitting

authority was enforcing adequate preconstruction review absent the notification

requirements in §63.5(f)(1). (IV-D-03) The commenter also believed that the

notification requirement was duplicative and burdensome, as EPA would already be

receiving a copy of all notifications submitted to the permitting authority, as required

under §63.13.

(IV-D-03)

Response:

We appreciate the commenter’s support for the concept of allowing construction or

reconstruction approval under State preconstruction review programs.

We generally agree with commenter IV-D-19 that a State or local agency that has

taken delegation of part 63 standards has already probably demonstrated that their

preconstruction review process is substantially equivalent to the Federal requirements. 

However, State requirements may differ from Federal requirements, and delegation of a

Federal requirement does not ensure equivalency of a State requirement. When a State is

the delegated authority, the State implements §63.5; we do not require two

preconstruction review processes when the State and Federal requirements are

substantially equivalent.

However, we believe the commenters have misconstrued the intent of these

provisions. The burden is not on the source to demonstrate the equivalency of a State

preconstruction review program. The intent of the provisions is to allow owners or
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operators of affected sources to notify the Regional Office of a State’s finding that their

preconstruction review program requirements are substantially equivalent to the General

Provisions’ preconstruction review requirements. Nonetheless, we agree that the

proposed language in §63.5(f)(1) could lead to potential confusion. Therefore, in order

to eliminate any potential for confusion, we have amended §63.5(f)(1) to no longer

require that an owner or operator demonstrate to the Administrator’s satisfaction that

the conditions of §63.5(f)(1)(i) and (ii) are met. Instead, §63.5(f)(1) specifies that the

Administrator will approve an application for construction or reconstruction if an owner

or operator meets the conditions of §63.5(f)(1)(i) and (ii). Additionally, §63.5(f)(1)(ii)

has been amended to require that an owner or operator provide a statement from “the

State or other evidence (such as State regulations) that it considered the factors specified

in §63.5(e)(1)” rather than requiring “the State (in it’s finding) consider factors

substantially equivalent to those specified in §63.5(e)(1).” 

Paragraph 63.5(f)(1) states that preconstruction review procedures that a State

utilizes for other purposes may be utilized if the procedures are substantially equivalent

to those specified in the General Provisions. We believe this adequately refers to

§63.5(e)(1) where the criteria for approval of construction or reconstruction are

described. 

Finally, we do not agree with the commenters’ suggestion that we determine which

State or local programs have substantially equivalent preconstruction review

requirements. Individual States or local agencies are in a better position to make such a

determination. 

2.8 Comments on Startup, Shutdown, and Malfunction

Provisions

2.8.1 General Duty to Comply [§63.6(e)(1)(i)]

Comment:

A few commenters supported the proposed changes to §63.6(e)(1)(i). (IV-D-02,

12, 14, 19, 25) The commenters noted that the proposed change clarifies that compliance

with the Startup, Shutdown, and Malfunction Plan (SSMP) during SSM constitutes

compliance with the standards. (IV-D-02, 12, 14, 19, 25) They also supported the

recognition that worker safety should be considered in determining what actions are taken

during a SSM event. (IV-D-12, 25) Two of the commenters noted that the changes

would not expose a source to double penalties for simultaneous violations or to

enforcement liability every time the source failed to follow an instruction in an owner’s

manual. (IV-D-02, 14)
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Two commenters questioned whether an action that is inconsistent with the SSMP

is a violation of the requirement in §63.6(e)(1)(i) to operate and maintain the affected

source to minimize emissions to the levels of the relevant standard. The commenters

requested that EPA identify the criteria (other than minimizing emissions) that 

implementing agencies should use in determining whether the requirements in

§63.6(e)(1)(i) are met. (IV-D-04, 18)

Response:

We appreciate the commenters’ support for changes made to the SSMP provisions.

The question of whether an action that is inconsistent with the SSMP is a violation

of the requirement to minimize emissions is for the enforcement agency to evaluate on a

case-by-case basis. The General Provisions require that actions taken that are

inconsistent with the SSMP be reported when the source exceeds the relevant emission

standard. The purpose of this notification is to provide the State with an opportunity to

evaluate whether the incident had an effect on the source’s requirement to minimize

emissions to the levels required by the relevant standard. It is possible to be inconsistent

and still minimize emissions. The SSMP can be revised as necessary when new SSM

procedures are warranted. In this way, the source owner/operator can minimize the

likelihood of operating in a manner that is inconsistent with the SSMP. For these

reasons, we have declined to identify general criteria for violation of minimizing

emissions as the commenters request. Instead, we believe these determinations are best

made by each implementing agency.

Comment:

One commenter believed that EPA should clarify control requirements for the time

between the process shutdown (ceasing operation) and startup (putting into operation). 

The commenter requested that EPA accomplish this by revising the definitions of startup

and shutdown. (IV-D-19) 

Response:

Once a source is subject to a NESHAP that includes a requirement for a SSMP, the

source must either meet the requirements of the standard or operate under the SSMP. It

is the source’s responsibility to determine how to operate during periods of SSM, and to

specify such procedures in the SSMP.

“Shutdown” specifically means only the process of shutting off equipment or a

process, and does not refer to the period of non-operation. Thus, during this period when

a process is offline or between production runs, the source must meet the standard,
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including emission limits, as well as monitoring, recordkeeping, and reporting

requirements. An owner or operator may apply to the Administrator for alternatives to

monitoring during these periods. Other provisions may be waived during longer periods

of non-operation, upon request. 

2.8.2 Do Not Incorporate SSMP Into Title V Permit [§63.6(e)(3)] 

Comment:

A few commenters supported removing the requirement in §63.6(e) that the SSMP

be incorporated into the title V permit. The commenters noted that incorporating the

SSMP into the title V permit is burdensome for sources and permitting authorities, as it

requires revisions to the title V permit whenever the SSMP is changed. (IV-D-02, 12, 14,

21, 25)

Response:

We appreciate the commenters’ support.

2.8.3 Criteria for Requiring SSMP Revisions [§63.6(e)(3)(vii)]

Comment:

Two commenters requested that EPA add a fourth instance in which a permitting

authority may require a facility to revise its SSMP in §63.6(e)(3)(vii), which would be if

the permitting authority determines that an event listed in the plan does not meet the

definition of startup, shutdown, or malfunction outlined in the General Provisions. The

commenter also requested that EPA specify whether any of the conditions in

§63.6(e)(3)(vii) constitute a violation of the SSMP provisions. (IV-D-04, 18)

Response:

We believe that §63.6(e)(3)(vii) (A) already implicitly gives permitting agencies the

authority to require a facility to revise its SSMP if an event listed in the SSMP does not

meet the definition of startup, shutdown, or malfunction in §63.2. However, we are

adding §63.6(e)(3)(vii) (D) to state this authority explicitly. The malfunction provisions

in subpart A are not intended to allow a source to willingly or inadvertently circumvent

the requirement to meet an emissions limitation or standard by labeling an event a

malfunction when it does not meet the definition of malfunction in §63.2.
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2.8.4 SSMP Revisions [§63.6(e)(3)(viii)]

Comment:

A few commenters opposed the requirement in §63.6(e)(3)(viii) that revisions to

the SSMP be reported to the permitting authority in the semiannual report. (IV-D-03, 19)

One commenter considered the new requirements in §63.6(e)(3)(viii) burdensome

and duplicative. The commenter believed that the requirements to submit reports of

actions taken that are consistent or inconsistent with the SSMP, to revise the SSMP, and

to keep copies of superseded SSMP on site were sufficient to ensure the permitting

authority is aware of changes to the SSMP. (IV-D-03)

One commenter stated that if the source can revise the plan without prior approval,

it makes no sense to have to send a file copy to EPA and the requirement for revisions to

be maintained on site in §63.6(e)(3)(v) should suffice. If EPA does mean that a revised

SSMP must be submitted, the Agency should give more detail on how it should be

formatted, including how the specific procedure or methodology relates to a particular

SSM event. The commenter also recommended that the date on the new SSMP should be

its effective date. On the other hand, if EPA only wants a notice that the SSMP has been

revised in the semiannual report, then §63.6(e)(3)(viii) should be revised to state that. 

The commenter also requested clarification on what the “scope of activities” in 

§63.6(e)(3)(viii) means. (IV-D-19).

The commenter also recommended that EPA explain how malfunctions that meet

the definition of SSM under §63.2, but are not covered in the existing SSMP, should be

reported. EPA should add language to §63.6(e)(3)(viii) to cover this situation. The

commenter cited §63.8(c)(1)(ii) and §63.10(d)(5)(ii) as requiring reports of malfunctions

not covered by the SSMP, but noted that subpart A does not specify how these

malfunctions should be reported. (IV-D-19)

Two commenters requested that EPA remove the last sentence of proposed

§63.6(e)(3)(ix) regarding the permit shield. The commenter believed the sentence could

be misconstrued to mean that the SSMP is part of the title V permit and yet ineligible for

the permit shield. (IV-D-12, 25)

Response:

We disagree that the requirements in §63.6(e)(3)(viii) are burdensome. This

section requires that EPA be notified in the semiannual report that revisions were made

to the SSMP, but it does not require that a file copy of the entire revised plan be

submitted.
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“Scope of activities” generally refers to the equipment and activities at the source

covered by the SSMP. It is the owner or operator’s responsibility to define the specific

scope of activities that the SSMP covers, as this is source-dependent. Moreover, these

provisions are designed to give the source owner/operator flexibility. Generally, the

scope of activities would include all operations and equipment specified by the owner or

operator that should be included in the SSMP. To the extent that these activities are

changed in the plan, we are requiring that the permitting authority be notified.

To comply with the rule, sources must either meet the standard or comply with the

SSMP. If a malfunction not covered by the SSMP occurs and the source meets the

standard, there is no need to report. If a malfunction not covered by the SSMP occurs

and the source does not meet the standard, the deviation must be reported. In any case,

when a malfunction occurs that was not included in the SSMP, the plan should be revised

to include the previously unincluded malfunction.

Finally, with respect to the comment regarding the applicability of the permit

shield, these commenters have misinterpreted the provisions of the rule. The proposed

amendments to the General Provisions concerning SSM plans were intended in part to

address concerns expressed by the petitioners, who believe that the language in the

current General Provisions requiring that the SSM plan be “incorporated by reference

into the source’s Title V permit” could be construed to require that permit revision

procedures be followed whenever an SSM plan is revised. We do not construe the

existing General Provisions in this manner, but we understand the concern expressed by

the petitioners. The amendments indicate that the permit must require that the owner or

operator adopt an SSM plan and then operate and maintain the source in accordance

with the plan, but they cannot reasonably be construed as requiring that each element of

the SSM plan be made an element of the permit. The provisions within the SSM plan will

not be terms and conditions of the permit except in the limited instance where a

permitting authority elects to incorporate them. Since the SSM plan is not itself part of

the operating permit, and it can be revised without revision of the permit, the SSM plan is

not eligible for the permit shield.

2.8.5 Immediate SSM Reports [§63.6(e)(3)(iv)]

Comment:

One commenter preferred that reports of SSM actions not consistent with the

SSMP be submitted with the periodic report, rather than within 2 working days after

commencing actions and 7 working days after the end of the event, as in §63.6(e)(3)(iv). 

The commenter maintained that most MACT standards allowed this, and EPA should be

consistent in its approach. Also, title V, the Superfund Amendments and Reauthorization
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Act (SARA), and Comprehensive Environmental Response, Compensation, and Liability

Act (CERCLA) already require immediate reporting, so the MACT requirements are

redundant anyway. (IV-D-19)

Response:

We decline to make the timeline change suggested by commenter. Each individual

NESHAP has the discretion to change this requirement. The consequences of not being

consistent with the SSMP vary for different sources and under different circumstances,

and developers of each NESHAP are in the best position to evaluate appropriate actions,

including the need to immediately report such inconsistencies, based on these

consequences.

2.8.6 SSMP Requirements Apply to Monitoring Equipment

[§63.6(e)(3)(iv)]

Comment:

Two commenters supported applying the SSMP provisions in §63.6(e)(3) to

monitoring equipment as well as air pollution control equipment. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.8.7 SSM Requirements Should Not Apply

Comment:

One commenter noted numerous specific provisions of proposed 40 CFR part 63,

subpart GGGG, National Emission Standards for Hazardous Air Pollutants: Solvent

Extraction for Vegetable Oil Production, conflicted with the proposed SSM requirements

for the General Provisions. The commenter urged EPA to clarify in the preamble to the

final General Provisions that the SSM requirements in the General Provisions do not

apply to sources subject to subpart GGGG. The commenter noted that EPA cannot

effectively reopen each affected regulation without taking and responding to public

comment on the changes. 

The commenter indicated that proposed §63.6(e)(3)(iii), which requires records

related to malfunctions under §63.10(b), should not apply to subpart GGGG, as subpart
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GGGG states that §63.10(b)(2)(ii-iii) relating to malfunction records do not apply. Also,

proposed §63.6(e) (3)(iv), which requires reporting of actions inconsistent with the SSMP

if the emissions exceed the relevant standard, does not comport with subpart GGGG. The

Vegetable Oil NESHAP require reporting of such actions regardless of whether the

standard was exceeded. The commenter also specifically noted that proposed

§63.6(e)(3)(viii), requirement to report modifications to the SSM plan in the semiannual

report, should not apply to sources subject to subpart GGGG, as subpart GGGG does not

require a semiannual report. (IV-D-07) 

Response:

We agree that the proposed amendments would have had a substantive impact on

the Vegetable Oil NESHAP. However, the commenter has misinterpreted the intent of the

changes, which was to reduce burden.

We agree with commenter IV-D-07’s assessment that certain startup, shutdown,

and malfunction provisions in the proposed amendments are inconsistent with the

promulgated Vegetable Oil NESHAP. We had previously reviewed the existing rules and

did not identify any substantive problems. However, the Vegetable Oil NESHAP were

promulgated after our review and subsequent proposal of the amendments. We have

discussed the implications with the commenter and as a result, we are amending, in a

separate Federal Register notice, several provisions in the Vegetable Oil NESHAP

related to SSM requirements to eliminate unintended inconsistencies. The Vegetable Oil

NESHAP include specifically tailored SSM provisions and, thus, sources covered by the

Vegetable Oil NESHAP should look to that rule for their applicable SSM provisions. 

Specifically, we are correcting the explanation column of Table 1 of §63.2870 as it

applies to §63.6(e) to state, “implement your plan as specified in §63.2852.” Table 1

also now indicates specifically that (§63.6( e)(3)(iii), (iv), and (viii) do not apply to

Vegetable Oil NESHAP affected sources; this clarifies that not all of §63.6(e) applies, as

the rule was originally promulgated.

We are also amending the first sentence of §63.2861(d) to clarify that

owner/operators must submit an immediate SSM report if an SSM is handled differently

from the procedures in the SSM plan and the emission standards are exceeded. We are

amending the first sentence of §63.2861(d) to read as follows: 

(d) Immediate SSM reports. If you handle a SSM during an initial startup period

subject to §63.2850(c)(2) or (d)(2) or a malfunction period subject to

§63.2850(e)(2) differently from procedures in the SSM plan and the relevant

emission requirements in §63.2840 are exceeded, then you must submit an

immediate SSM report.
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We are also amending the third sentence of §63.2852 to clarify that the SSMP does

not have to be incorporated into the title V permit. We are amending the third sentence

of §63.2852 as follows:

§63.2852 What is a startup, shutdown, and malfunction plan?

You must develop a written SSM plan in accordance with §63.6(e)(3) and

implement the plan when applicable. You must complete the SSM plan before the

compliance date for your source. You must also keep the SSM plan on-site and

readily available as long as the source is operational. 

These changes will ensure the minimization of emissions at all times, clarify the

SSM requirements, and specify the relationship of the General Provisions to Vegetable

Oil NESHAP affected sources. 

2.8.8 Availability of SSMP

Comment:

A few commenters strongly opposed the statements in the proposal preamble on

page 16326 that the SSMP must be submitted to the permitting authority and made

publicly available if someone requests it. (IV-D-02, 03, 14) One of the commenters

believed it would be burdensome to prepare a SSMP without Confidential Business

Information (CBI) in it. Also, such a plan would be uninformative without the CBI. (IVD-03)

Two other commenters preferred that the rule specifically state that the permitting

agency has the authority to request a copy of the facility’s SSMP and to review and

comment on it. This commenter also preferred that State and local agencies have

discretion to approve or disapprove the SSMP. (IV-D-04, 18)

Response:

We believe that the proposal preamble discussion on page 16326 accurately

reflects §70.4(b)(3)(viii) of the title V permit program, which requires that the permitting

authority has legal authority to: “Make available to the public any permit application,

compliance plan, permit, and monitoring and compliance certification report pursuant to

section 503(e) of the Act, except for information entitled to confidential treatment

pursuant to section 114(c) of the Act. The contents of a part 70 permit shall not be

entitled to protection under section 114(c) of the Act.” For this reason, we do not agree

with the commenters who oppose the requirements for the SSMP to be made publicly

available if requested. Owners or operators may still identify the portions of the SSMP
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32

that are considered Confidential Business Information (CBI); material claimed as CBI

would not be available for public disclosure except as provided under the process

established by 40 CFR Part 2. 

We further believe, pursuant to §70.4(b)(3)(viii), that the authority for permitting

agencies to request a facility’s SSMP already exists. Therefore, we do not believe it is

appropriate at the present time to revise the regulation as commenters IV-D-04 and 18

request.

2.8.9 Contents of SSMP

Comment:

One commenter requested that EPA require that facilities provide the number and a

description of malfunctions that occurred in the semiannual report. The commenter

stated that this information would be necessary to evaluate a facility’s compliance with

the SSMP, as regular site visits are infeasible due to limited resources. (IV-D-04)

Response:

We agree with the commenter and we have modified the provisions at

§63.10(d)(5)(i) to state “Periodic startup, shutdown, and malfunction reports . . . .

Reports shall only be required if a startup, shutdown, or malfunction occurred during the

reporting period, and they shall include the number, duration, and a brief description

of each startup, shutdown, and malfunction...” This change provides the implementing

agency with adequate information, without placing an undue additional burden on the

source. The types of malfunctions will already have been identified in the SSMP, so a

brief description could consist of simply identifying which types of malfunctions occurred

during the reporting period, as well as the number and the duration of each. 

Comment:

One commenter requested that EPA identify in the regulation the minimum

required elements of a SSMP. (IV-D-04) 

Response:

The minimum criteria that are generally applicable for a SSMP are included in

§63.6(e)(3)(i). Other requirements may be specified in an individual NESHAP if

necessary, because the possible requirements for a SSMP are too varied depending on

the particular source categories and sources concerned to specify all such elements in the
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33

General Provisions. If the permitting authority is not satisfied with a particular SSMP,

the permitting authority may require that it be revised.

2.9 Other Comments on §63.6, Compliance with Standards and

Maintenance Requirements

2.9.1 Compliance Requirements for Area Sources That Become

Major [§63.6(b)(7) and (c)(5)]

Comment: 

Two commenters supported the proposed revisions to §63.6(b)(7) and (c)(5)

regarding compliance requirements for area sources that become major. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

Comment:

One commenter requested that EPA clarify its statements in the preamble on page

16328 regarding area sources that become major. The commenter believed that EPA had

improperly characterized the regulatory requirements for such sources. The commenter

believed that EPA was incorrect in stating that §63.6(b)(7) and (c)(6) were being revised

regarding the applicability of MACT to area sources. The commenter stated that the

current rule is that when minor sources become major, they are subject to MACT for

existing sources. The commenter believed that making minor sources subject to new

source MACT would effectively shut down such sources because they would not be able

to operate with new source MACT on the date that they became major. (IV-D-10)

Response:

We agree with the commenter that the preamble improperly characterized the

requirements for area sources that become major in the following text from page 16328 :

“The current General Provisions require new source MACT for area sources that

become major after the effective date of the relevant standard, regardless of when the

portion of the source affected by the standard (the affected source) actually commenced

construction (including those that commenced construction long before the proposal date

of the NESHAP).” The commenter is correct that under the General Provisions

promulgated on March 16, 1994 at 59 FR 12430, an existing area source that becomes a
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major source is subject to existing source standards. [§63.6(c)(5)]. Under the 1994

regulations, an unaffected new area source (that is, an area source for which

construction or reconstruction was commenced after the proposal date of the standard)

that becomes a major source is subject to the new source standards. 

However, the changes were made to §63.6(c)(5), not §63.6(c)(6), as the commenter

indicated. Our statements in the preamble regarding the proposed changes to

§63.6(b)(7) and §63.6(c)(5) are accurate.

2.9.2 Compliance Extension 120 Days Before Compliance Date

[§63.6(i)(4)(i)(B)]

Comment:

Several commenters supported allowing compliance extension requests to be

submitted as late as 120 days before the compliance date, rather than 1 year out. (IV-D03, 12, 15, 20, 21, 25) One commenter believed this change would reduce the number of

compliance extension requests. (IV-D-15) Another commenter outlined many

circumstances that could arise that would necessitate a late request for a compliance

extension, such as vendor strikes, acts of God, or damaged equipment. (IV-D-03) 

One commenter supported the proposed provision in §63.6(i)(4)(i)(B) postponing

the applicability of MACT standards until the permitting authority either approves or

denies a compliance extension request. This commenter noted that the proposed

compliance extension revisions were extremely important for sources subject to 40 CFR

part 63, subpart EEE, National Emission Standards for Hazardous Air Pollutants for

Hazardous Waste Incinerators. Amendments to the performance test requirements of the

Hazardous Waste Incinerator rule have not been completed. The commenter noted that

the amendments would have had to be promulgated by December 2001 for facilities to

complete their comprehensive performance test plans by the March 2002 deadline. The

ability to apply for a compliance extension would be critical if the amendments were not

final by December 2001. (IV-D-21) 

Response:

We appreciate the commenters’ support.
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2.9.3 Compliance Extension Later Than 120 Days Before

Compliance Date [§63.6(i)(4)(i)(C)]

Comment:

A few commenters supported allowing compliance extension requests to be

submitted even later than 120 days before the compliance date when the need arose due to

circumstances beyond the reasonable control of the owner/operator. (IV-D-12, 20, 25)

One of the commenters identified various unforeseen and uncontrollable problems that

would create a need for a compliance extension later than 120 days before the compliance

date, including strikes, transportation delays, acute labor shortages, software glitches, and

natural disasters. In such circumstances, the ability to submit a compliance extension

request later than 120 days before the compliance date would help to avoid facility

shutdowns. (IV-D-25)

Response:

We appreciate the commenters’ support.

2.9.4 Criteria for Compliance Extension [§63.6(i)]

Comment:

A few commenters requested that EPA add specific minimum criteria for granting

a compliance extension in the regulations at §63.6(i). The commenter recommended that

the criteria include a good faith effort to comply (that is, a list of actions taken to date),

circumstances beyond the reasonable control of the facility, and a reasonable compliance

schedule. The commenter noted that minimum criteria would ensure consistency,

especially when a company owns sources in multiple States. (IV-D-04, 18)

Response:

Some of the criteria mentioned by the commenter are included in the General

Provisions at §63.6(i)(6)(i). Beyond the elements identified in that paragraph, which

include a description of controls, compliance schedule, and interim emission control

steps, it is at the permitting authority’s discretion to evaluate compliance extension

requests on a case-by-case basis. If the permitting authority does not agree that a

compliance extension is warranted, they have the authority to disapprove the request. 
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2.9.5 Routine Maintenance Not During Scheduled Downtime

Comment:

A few commenters applauded EPA’s recognition on page 16327 of the proposal

preamble that there are times when planned routine maintenance of an air pollution

control device cannot be scheduled to coincide with scheduled downtime of the process

equipment. (IV-D-02, 03, 14, 20) One of the commenters urged EPA to indicate whether

they intend to revise the regulations to incorporate this concept. (IV-D-03) Another

commenter endorsed the preamble language asking affected sources to suggest potential

allowances for routine maintenance in individual MACT standards (for example,

allowing the use of thermal oxidizers to control emissions from Group 1 process vents

under the HON). (IV-D-20)

Another commenter advised EPA to require offsets for any excess emissions

occurring during routine maintenance by using a back-up control device or by reducing

emissions elsewhere in the plant if there is no back-up control device. The offset

amounts must be equal or greater than the excess emissions. Risk assessments or hazard

evaluations would not be required. The definition of shutdown in the General Provisions

does not include air pollution control equipment, so this definition would need to be

revised. (IV-D-18)

Response:

We appreciate the commenters’ support. As we indicated in the preamble, there is

no uniform approach to this issue that will be appropriate for every MACT standard. 

Therefore, this issue will be addressed if needed during regulatory development for the

various MACT standards. As we also indicated in the preamble, we encourage the public

to actively participate in the development of each MACT by suggesting potential

allowances for routine maintenance if appropriate.

2.10 Comments on §63.7, Performance Testing Requirements

2.10.1 Conduct Performance Test Within 180 Days of Compliance

Date [§63.7(a)(2)]

Comment:

A few commenters supported the proposed change to §63.7(a)(2), which would

require performance tests to be conducted within 180 days of the compliance test date in

all cases. (IV-D-02, 14, 19)
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37

Response:

We appreciate the commenters’ support for the proposed changes.

Comment:

One commenter recommended that EPA add a paragraph to allow extensions of the

performance test date for control devices that have already demonstrated initial

compliance but need to be retested. The commenter stated that §63.6(i) provides some

allowances for performance test extensions (such as for existing sources demonstrating

compliance with early reductions, BACT or LAER requirements, or for existing sources

that need additional time to install controls), but does not address the situation where an

existing source has already installed controls and demonstrated compliance. The

commenter expressed two concerns: (1) lack of clarity regarding compliance dates or

testing requirements under particular circumstances; and (2) reaching representative

operating conditions during initial start-up. For example:

• Some MACT standards (like the HON) specify the compliance

date for process units added to existing affected sources for which

new source requirements do not apply, while others do not. The

commenter recommended that EPA clarify this. Further, some

MACT standards permit the use of previous performance tests for

demonstrating compliance, provided that either no process changes

have occurred or the test can “reliably demonstrate compliance”

despite process changes. The commenter assumed that a re-test is

needed when this standard is not met, but requested clarification

from EPA.

• The commenter noted that initial startup is a process whose length

can vary depending on the equipment involved, and that it is not

defined in the regulation. To meet the requirement to conduct

performance testing within 180 days, affected sources may be

required to test under conditions that are not representative of

normal operating conditions, and then to re-test at a later date when

the source is running as intended. The commenter stated that such

additional testing is expensive and gave several examples of

situations where representative operating conditions might not

occur in the 180-day time period.

The commenter maintained that the circumstances described above illustrate the

need for provisions to allow sources to request performance test extensions. The

commenter suggested that one or a combination of the following options could be used: 
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• Add a paragraph to §63.7(a)(2) to allow EPA or the permitting

agency to grant requests to extend the date for performance testing

(or re-testing) of existing control devices that have already

demonstrated initial compliance.

• Add language to §63.6(i) or §63.7(h)(3)(ii) to provide such

performance test date extensions.

• Clarify that §63.7(e)(1) allows an affected source to delay a

performance test when representative operating conditions are not

reached during initial start-up.

The commenter recommended that the first option be implemented. (IV-D-19)

Response:

While we acknowledge the commenter’s concerns, we do not agree that a

regulatory change to the General Provisions is warranted to address these issues. As the

commenter noted, some MACT standards, such as the HON, specify compliance dates for

additions or changes to existing affected sources that do not result in new source

requirements. Where a situation is particularly complex, the individual standard will

address the question of compliance dates, and we believe that this is the appropriate way

to handle such concerns. A source owner/operator can always request a determination

from the permitting agency if the compliance or performance testing requirements are in

doubt.

With respect to the commenter’s concern about performance testing under

representative operating conditions, we believe that this issue is already adequately

addressed. First of all, for existing sources, the source has already been in operation for

some time, and thus, representative operating conditions are known by the

owner/operator. For new sources, the compliance date is sufficiently far in the future

that the question of reaching representative operating conditions should be moot.

Furthermore, most of the 10-year MACT standards are being written to address these

types of situations. Again, this is a matter best addressed by individual rules when

necessary. 

Finally, a source owner/operator also has the discretion to apply for permission to

use an alternative test method under §63.7(f), or for the waiver of a performance test

under §63.7(h). 
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2.10.2 Notify of Performance Test Delay As Soon As Practicable

[§63.7(b)(2)]

Comment:

Two commenters supported the proposed change in §63.7(b)(2) that would allow

owners to notify EPA as soon as practicable rather than 60 days prior when a performance

test date must be rescheduled. The commenters noted that it is often difficult to give

advance notice of testing dates, as operators are often at the mercy of overburdened

testing facilities in scheduling a test. (IV-D-02, 14) 

One commenter noted a discrepancy between the preamble language discussing

performance testing notification requirements and the actual proposed language. The

commenter quoted text from the preamble that indicated that when an owner/operator was

unable to provide at least 60 days calendar notice before a performance test was

scheduled, notification must be submitted within 5 days of the test date. However, the

commenter pointed out that the rule language in question discusses only notification

periods for the case when a performance test cannot be conducted on the scheduled date.

The commenter requested that EPA clarify its intent. (IV-D-19)

Response:

We appreciate the commenters’ support for the proposed changes.

Commenter IV-D-19 is correct regarding the discrepancy between the preamble

statement and the proposed requirements in §63.7(b)(2). The proposal preamble (see

page 16330, section J.2) stated: “Section 63.7(b) of the General Provisions provides

performance test notification requirements that we and/or the delegated State agencies be

notified at least 60 calendar days before the scheduled date of the performance test.” 

Our intent is reflected in the rule language of §63.7(b)(2). However, to better distinguish

between the requirements of §63.7(b)(1) and (2), we amended §63.7(b)(1) to state that an

owner or operator must notify the Administrator of his or her intent to conduct a

performance test at least 60 calendar days before the performance test is “initially”

scheduled to begin. 

2.10.3 Use Alternative Method If Not Approved Within 45 Days

[§63.7(c)(3)(ii)(B)]
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Comment:

One commenter supported the proposed changes to §63.7(c)(3)(ii)(B), which

would allow the owner/operator to conduct a performance test using an alternative

method if the Administrator has not notified the owner of approval within 45 days after

the request or a site-specific test plan containing the proposed alternative method was

submitted. (IV-D-21)

Response:

We appreciate the commenter’s support.

2.10.4 Alternatives to Method 301 [§63.7(f)(2)(ii)]

Comment:

A few commenters supported the proposed changes to §63.7(f)(2)(ii) allowing the

use of specific procedures in Method 301, rather than the entire Method. (IV-D-02, 14,

19)

Response:

We appreciate the commenters’ support.

2.10.5 Permitting Authority Approves Alternative Test Methods

[§63.7(f)(2)(i) and §63.7(f)(3)]

Comment:

One commenter believed the permitting authority should be able to approve the use

of alternative test methods after a title V permit has been issued to the source

owner/operator. The commenter suggested specific language for §63.7(f)(2)(i) and (3) to

implement this change. The commenter believed the State agency would be more

familiar with the facility since they are closely involved with the facility during the

construction permit phase. The commenter asserted that the permitting authority should

have the same goals and objectives as EPA does for considering alternative requests, as

the title V permit must meet federal requirements. Having the permitting authority

approve the alternative test methods would relieve the facility of the burden to submit

requests to both the permitting authority and EPA. (IV-D-19)
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Response:

We stated our policy regarding approval of alternative test methods in our

November 12, 1986 memo from Jack Farmer, New Section for all NSPS and NESHAP

Regulations: Delegation of Authority. A memorandum from John Seitz on July 10, 1998,

Delegation of 40 CFR Part 63 General Provisions Authorities to State and Local Air

Pollution Control Agencies, updated the policy. This policy is also included in

Delegation 7-121, Performance Test, of our Delegations Manual. All of these documents

are included in our publication 305-B-99-004, How to Review and Issue Clean Air Act

Applicability Determinations and Alternative Monitoring, which you can find at 

http://www.epa.gov/clariton/clhtml/pubtitle.html. We also made changes to the

regulations at 40 CFR Part 63, Subpart E, Approval of State Programs and Delegation

of Federal Authorities to allow EPA to approve the use of alternative test methods. The

preamble to the final rule discusses our rationale for this change. You’ll find the

preamble at 65 FR 55810. As these documents and the promulgated regulations state,

only the Administrator may approve alternatives to test methods for demonstrating

compliance with emission limitations under section 112(d). We disagree with the

commenter that the permitting authority is in the best position to make these decisions.

Intermediate changes without a thorough review have the potential to decrease the

stringency of the standard, and typically require substantial technical information. 

Major changes or alternatives to test methods have national significance, and therefore

must be reviewed and approved by the Administrator. Furthermore, §63.7(f) requires

Method 301 validation for intermediate and major changes to test methods; this is an

extensive validation method for which the permitting authority generally does not have

adequate time or resources. Finally, for the permitting authority to make these decisions

could result in different decisions for similar sources.

2.10.6 Definition of Minor, Intermediate and Major Changes

[§63.7(e)(2)(i) and (ii), §63.8(b)(i) and (ii), 63.8(f)(1)]

Comment:

One commenter stated that the definitions of minor, intermediate, and major

changes were not included in §63.90(a), and it is therefore difficult to understand the

criteria for each. If the definitions are not available in a currently promulgated rule, EPA

should add them to subpart A. (IV-D-19)

Response:

The definitions are included in amended §63.90(a), which was promulgated on

September 14, 2000 at 65 FR 55810.
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2.11 Comments on §63.8, Monitoring Requirements 

2.11.1 CMS Operation and Maintenance [§63.8(b)(2)]

Comment:

Two commenters supported the proposed changes to §63.8(b)(2) that allow the use

of a single CMS for monitoring combined emission streams. The commenters noted that

this provision would reduce cost and burden. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.11.2 CMS Operation and Maintenance [§63.8(c)(1)]

Comment:

A few commenters supported EPA’s proposal to delete the requirement in

§63.8(c)(1)(ii) for reporting actions not consistent with the SSMP with 24 hours. The

commenters appreciated making the requirements consistent with initial reporting within

2 working days and final reporting within 7 working days, as required in §63.6(e)(3),

which §63.8(c)(1) now references. (IV-D-02, 14, 19)

Response:

We appreciate the commenters’ support.

2.11.3 Readily Accessible Readout [§63.8(c)(2)]

Comment:

Two commenters supported the requirement for readouts to be readily accessible. 

(IV-D-02, 14)

Several commenters proposed deleting the requirement that readout from the

monitoring equipment be “readily accessible onsite for operational control or inspection

by the operator of the equipment.” (IV-D-10, 13, 19) One commenter maintained that
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43

the provision was unnecessary because §63.10(b) already requires files of all information

to be readily available. (IV-D-19) A few of the commenters maintained this requirement

was technically infeasible, as the readout depends on the configuration of the source, type

of control equipment, frequency, and whether monitoring data are read in central control

booths or computers. (IV-D-10, 13, 19) One commenter (IV-D-13) stated that the

optimal location of the readout should be left to the source.

One of the commenters stated that if EPA does not remove the phrase, it should be

reworded to change the regulatory text from “read out” to “indication of operation,” as

audible or visual alarms may also alert the operator that a problem has occurred with the

continuous monitoring system (CMS). The commenter further suggested removing the

terms “in plain view” and “close proximity,” as CMS readouts may be readily accessible

but may not meet these requirements. For example, they may be in the control room but

not in the line-of-sight of an operator, in the process unit operating block but not where

the “operators are normally operated,” or operated by a different process unit and

monitoring unit. The commenter proposed the following language if EPA does not delete

§63.8(c)(2)(ii) entirely. (IV-D-19)

“Unless the individual subpart states otherwise, the owner/operator shall ensure

that the response (indication of operation) from each CMS required for compliance

with the standard is readily accessible on-site for operational control or inspection

by the operator of the equipment.” 

Response:

We recognize the commenters’ concerns with the provisions governing the

availability of information from monitoring equipment. We have revised §63.8(c)(2)(ii)

to refer to “read out or other indication of operation.” This addresses the point made by

commenter IV-D-19, who pointed out that audible or visual alarms may be in use rather

than a “read out.” The terms “in plain view” and “close proximity” were used in the

preamble, although not in the regulatory text, to explain what was meant by readily

accessible and to assure that inspectors would have easy access to monitoring

information. However, we agree with the commenter that the required information may

be readily accessible although not in plain view. “Readily accessible” is the source

owner/operator’s responsibility to ensure that monitoring information is easily available. 

No rule changes were made to address this issue.
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2.11.4 Zero and High Level Calibration Checks [§63.8(c)(6)] 

Comment:

A few commenters suggested that EPA revise §63.8(c)(6) to clarify that the zero

and high-level calibration checks only apply to continuous emission monitoring systems

(CEMS) and continuous opacity monitoring systems (COMS), not to all CMS. Some

continuous parameter monitoring systems (CPMS), such as thermocouples and weight

devices, cannot be automatically calibrated. (IV-D-08, 12, 15, 25)

One commenter preferred that EPA delete §63.8(c)(6), as promulgated MACT

standards already contain calibration requirements and daily system checks for CPMS. 

The commenter cited §63.118(a)(2) and §63.152(f). (IV-D-19)

Response:

To address the commenters’ concern about CPMS that cannot be automatically

calibrated, we have revised §63.8(c)(6) as follows: “The owner or operator of a CMS

that is not a CPMS, which is installed in accordance with the provisions of this

 part . . .” The calibration specifications for a CPMS are described in the last sentence

of this paragraph.

It is not appropriate to delete §63.8(c)(6) as commenter IV-D-19 suggests.

Individual standards may change this as appropriate or necessary, but these monitoring

provisions will remain in the General Provisions.

2.11.5 Permitting Authority Approves Alternative Monitoring

[§63.8(f)(1)]

Comment:

One commenter believed the permitting authority should be able to approve the use

of alternative monitoring after a title V permit has been issued to the source

owner/operator. The commenter suggested specific language for §63.8(f)(1) to

implement this change. The commenter believed the State agency would be more

familiar with the facility since they are closely involved with the facility during the

construction permit phase. The commenter asserted that the permitting authority should

have the same goals and objectives as EPA does for considering alternative requests, as
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45

the title V permit must meet federal requirements. Having the permitting authority

approve the alternative monitoring would relieve the facility of the burden to submit

requests to both the permitting authority and EPA. (IV-D-19)

Response:

We stated our policy regarding approval of alternatives to any monitoring 

methods in Delegation 7-121, Alternative Methods, of our Delegations Manual. A

memorandum from John Seitz on July 10, 1998, Delegation of 40 CFR Part 63 General

Provisions Authorities to State and Local Air Pollution Control Agencies, updated the

policy. These documents are included in our publication 305-B-99-004, How to Review

and Issue Clean Air Act Applicability Determinations and Alternative Monitoring, which

you can find at http://www.epa.gov/clariton/clhtml/pubtitle.html. We also made changes

to the regulations at 40 CFR Part 63, Subpart E, Approval of State Programs and

Delegation of Federal Authorities to allow EPA to approve the use of alternative test

methods. The preamble to the final rule discusses our rationale for this change. You’ll

find the preamble at 65 FR 55810. As these documents and the promulgated regulations

state, only the Administrator may approve alternatives to any monitoring methods for

demonstrating compliance with emission limitations under section 112(d). We disagree

with the commenter that the permitting authority is in the best position to make these

decisions. Intermediate changes without a thorough review have the potential to

decrease the stringency of the standard, and typically require substantial technical

information. Major changes or alternatives to monitoring methods have national

significance, and therefore must be reviewed and approved by the Administrator. 

Finally, for the permitting authority to make these decisions could result in different

decisions for similar sources. For discussion of major, intermediate, and minor changes

to testing and monitoring, please see our July 10, 1998 policy memo, Delegation of 40

CFR Part 63 General Provisions Authorities to State and Local Air Pollution Control

Agencies, which is Attachment 1 of our publication 305-B-99-004.

2.12 Comments on §63.9, Notification Requirements

2.12.1 Initial Notifications [§63.9(b)]

Comment:

A few commenters supported removing the requirements to include design

capacity and information about each emission point in the Initial Notification under

§63.9(b)(2)(iv). (IV-D-02, 14, 19) 
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46

One of the commenters preferred that EPA remove the Initial Notification

requirements completely. The commenter maintained that EPA identifies all potential

existing sources in the MACT rule development process and has made that information

available to the permitting authorities and the public. The few and relatively small

sources that EPA does not identify in the regulatory development process will have to file

precompliance reports. Sources that are to be constructed, reconstructed, or that become

major by increasing emissions are already required to submit an application for

preconstruction review and approval; therefore EPA will have information about sources

that become subject to the standards after promulgation. The commenter explained that

the start-up date and whether the source was an area source were the only two pieces of

information that EPA would not have if the Initial Notification report were deleted. Each

MACT rule could address whether this information was needed. The commenter also

stated that removing the Initial Notification requirement from subpart PPP, Polyether

Polyols Production, has not created a problem. (IV-D-19)

Another commenter opposed the initial notification requirements, stating that they

are superfluous because the same information is required in the application for a new or

revised permit. (IV-D-22) 

One commenter also believed the provisions in §63.9(b)(1), (2), and (5) concerning

submitting applications for approval of construction or reconstruction were intended to

apply to nonmajor emitters. The commenter preferred that EPA clarify that these

provisions do not apply to nonmajor emitters. (IV-D-19)

Response:

We disagree with the commenters’ suggestions to remove all or part of the Initial

Notification requirements. Individual NESHAP may remove the initial notification

requirements but it is not appropriate to take them out of the General Provisions. It is

not our experience that every rule development process identifies every source that a

NESHAP affects; furthermore, sources may change over time. Therefore, initial

notification is a valid requirement, and does not impose an undue burden on source

owners or operators.

The requirements in §63.9(b)(1), (2), and (5) referred to by commenter IV-D-19

refer to notifications of the intent to construct or reconstruct, not applications for

approval of construction or reconstruction. These notifications apply to nonmajoremitting affected sources, although the applications for approval do not.
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2.12.2 No Analysis of Area Source Status in Notification of

Compliance Status [§63.9(h)(2)(i)(E)]

Comment:

Two commenters supported the proposed changes to §63.9(h)(2)(i)(E), in which

area sources are no longer required to submit an analysis demonstrating that the source is

an area source. (IV-D-02, 14)

Response:

We appreciate the commenters’ support.

2.12.3 Notification Requirements for Nonmajor Sources

Comment:

One commenter requested clarification on the notification requirements for

nonmajor-emitting sources. The commenter believed text was missing from the

following sentence in the last sentence of column 1 of the preamble on page 16330: “...we

are proposing to revise §63.9(b)(5) to allow a nonmajor-emitting sources that is not

subject to the requirements to submit an application for preconstruction review and

approval...” The commenter noted that a nonmajor source would not be subject to the

General Provisions and would not have to submit any notification. (IV-D-03)

Response:

We agree with the commenter that the sentence in question is confusing, because it

did not specify that the sources being discussed were nonmajor-emitting affected sources.

The text should have read “ ... we are proposing to revise §63.9(b)(5) to allow a

nonmajor-emitting affected source that is not subject to the requirements to submit an

application for preconstruction review and approval to request a reduction in the

information required in the application to construct or reconstruct.” Also, the proposal

preamble discussion at 16325/3 explains these requirements in §63.9(b)(5) further. A

nonmajor-emitting affected source is not required to submit an application for approval

of construction or reconstruction. However, a nonmajor-emitting affected source must

notify the Administrator of its intent to construct or reconstruct. Note that a nonmajor

emitting affected source could be part of a major source.

2.12.4 Timing of Notification of Compliance Status [§63.9(h)(2)(ii)]

Comment:
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48

One commenter requested revisions to the timing of submittal of compliance status

reports. This commenter noted that §63.9(h)(2)(ii) requires that the Notification of

Compliance Status report be submitted within 60 days of completing a compliance

demonstration as specified in the relevant standard. However, the commenter stated that

a typical affected source may consist of more than one device that requires performance

testing or other compliance demonstrations. This would then result in the need for

multiple compliance status reports. The commenter recommended that §63.9(h)(2)(ii) be

revised to require only a single Notification of Compliance Status for an affected source,

to be submitted 60 days after the completion of all required compliance demonstrations. 

Where opacity or visible emission observations are required, the commenter suggested

that the notification be required within 30 days of completion of the observations. The

commenter further recommended adding language to specify that the notification is due

by these dates “or as stated in the relevant standard.” (IV-D-19)

Response:

We believe that the commenter has misinterpreted the provisions of the rule. Our

intent in the rule is to do what the commenter suggests, as long as the requirements have

a common compliance date. The notification of compliance status is to demonstrate

compliance with the emission limitations and standards in their entirety, not just a

portion of them. This does not mean that if one portion of a standard has a different

compliance date (for example, the 6 month compliance period for equipment leaks under

the HON) that compliance with those requirements can be delayed until the later

compliance dates. Although not part of the proposal, we are making a clarification. We

have revised §63.9(h)(2)(ii) to state “ ...following completion of the relevant compliance

demonstration activity (or activities that have the same compliance date) specified in the

relevant standard...” to clarify. In addition, as a matter of EPA policy, all the 10-year

MACT standards will include a specific compliance date, which will further clarify these

requirements.

2.12.5 Adjustments to Timelines [§63.9(i)(3)]

Comment:

One commenter noted that §63.9(i)(3) contains provisions for approvals of requests

for adjustments to time periods or postmark deadlines and requires the Administrator to

respond to such a request “within 15 calendar days of receiving sufficient information to

evaluate the request.” The commenter stated that in practice this process does not work

well and gave examples of where this has resulted in lengthy delays between the request

and approval. The commenter recommended that §63.9(i)(3) be modified to allow the
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49

owner/operator to assume approval of the request if written disapproval is not received

within 90 days. (IV-D-19)

Response:

The language referred to by the commenter was not proposed to be amended in

this action, and will not be modified here. We appreciate the commenter’s concern

regarding timely review of requests to alter time periods or deadlines, and we are making

every effort to meet these time periods. We regret any inconvenience or difficulty that

occurs when review and approval are late.

2.13 Comments on §63.10, Recordkeeping and Reporting

Requirements

2.13.1 Applicability Determinations [§63.10(b)(3)]

Comment:

Two commenters supported the proposed changes to §63.10(b)(3) that would

require a record of applicability determinations only for sources within the source

category that the relevant standard regulates. (IV-D-02, 14)

One commenter requested that EPA clarify specifically what the applicability

determination certification must state. (IV-D-02) 

Response:

We appreciate the support of commenters IV-D-02 and 14. In general, the

applicability determination must state that the stationary source is in the source category

regulated by a relevant standard, for the reasons identified in an analysis or other

information prepared by the owner/operator.

2.13.2 Quarterly Reporting After Excess Emissions [§63.10(e)(3)]

Comment:

One commenter opposed increasing the reporting frequency for CMS under

§63.10(e)(3)(i)(C) when excess emissions occur. The commenter believed this change

would double the regulatory burden without improving compliance. The commenter also
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requested that EPA drop the term “directly for compliance purposes” since it is unclear

what data are used directly for compliance purposes. (IV-D-03)

Response:

We agree with the commenter. Section 63.10(e)(3)(i)(C), containing the

requirement to increase the reporting frequency after the occurrence of excess emissions,

was reserved in the General Provisions during burden reduction efforts. (See 64 FR

7467, 2/12/1999). We inadvertently, and incorrectly, reinstated it in the proposed

amendments. We have reserved this paragraph in the promulgated rule.

Comment:

One commenter requested that EPA delete the summary report items listed in

§63.10(e)(3)(vi)(I) - (J), which include emissions and CMS performance summary data,

and the criteria under §63.10(e)(3)(vii)-(viii), which explain whether the summary report

or the full report must be submitted. The commenter stated that the criteria for

calculating percentages of excess emissions and CMS downtime were vague enough that

it is difficult and burdensome to calculate the total duration of excess emissions. Also,

the term excess emissions is never really defined in subpart W, National Emission

Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon

Polyamides Production. The commenter recommended that the percentages in the

summary report [items §63.10(e)(3)(vi)(I) -(J) and criteria in §63.10(e)(3)(vii)-(viii)] be

deleted and the sources be required to submit the full excess emissions and monitoring

system performance report. If excess emissions occur during SSM, the report would

include actions taken for the event, circumstances of the event, reasons for not following

the SSMP, and whether excess emissions or parameter monitoring exceedances are

believed to have occurred. The commenter noted that EPA eliminated the requirement to

calculate the percentage of time an SSM event occurs and the reporting exemption

associated with it in the Consolidated Air Rule (CAR).

Next, the commenter stated that if EPA does retain the Summary Report items and

criteria, then EPA should clarify what SSM information the source must include in the

excess emissions and monitoring system performance report. Specifically, EPA should

clarify what to report if there are multiple CMS within a process unit, what periods of

CMS inoperation or malfunction should be included in the percentage calculation, and

which periods of CMS inoperation or malfunction should be included in the excess

emissions and monitoring system performance reports. The EPA should also clarify what

periods of SSM should be included in the percentage calculation, and which periods of

SSM should be included in the excess emissions and monitoring system performance

report. The commenter recommended that the percentage of excess emissions be
51

calculated for each emission point, considering the operating time of each individual

emission point. If only one emission point exceeds 1 percent of the affected source’s

operating time, the report would only contain the information for that emission point. 

(IV-D-19)

Response:

The provisions referred to by the commenter were not proposed to be amended in

this rulemaking, and will not be changed at this time. While we appreciate the

commenter’s concern, we believe that, in practice, this concern will be alleviated by the

fact that individual NESHAP have the discretion to override these requirements as

appropriate.
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Chapter 3 - Comments and Responses on Section 112(j)

3.1 Overview

The comments on the proposed amendments to subpart B of 40 CFR part 63

[Requirements for Control Technology Determinations for Major Sources in Accordance

with Clean Air Act Sections, Sections 112(g) and 112(j)] were primarily concerned with

the relationship between MACT determinations under different sections of the Act,

changes to the title V permit application and approval process, and the Agency’s

proposed prohibition on backsliding.

3.2 General Comments on Section 112(j)

3.2.1 Support Proposal

Comment:

Several commenters generally endorsed the proposed amendments to section

112(j). (IV-D-06, 11, 12, 17, 24, 25) A few of these commenters also stated that the

proposed regulations reasonably reflect the resolution of issues negotiated between EPA

and industry petitioners. (IV-D-06, 11, 12, 25) 

Response:

We appreciate the commenters’ support.

3.2.2 Agency Authority to Defer Case-by-Case MACT 

Comment:

Two commenters requested that EPA explicitly confirm its discretionary authority

to defer case-by-case MACT proceedings under section 112(j) when a national MACT

standard is under development. (IV-D-17, 24) Furthermore, one commenter maintained

that EPA should codify its intent to do this and the criteria it would use to grant such

deferrals. (IV-D-17) The commenter believed that without this provision, many case-bycase MACT determinations could be unnecessarily triggered for certain facilities before

the section 112(d) MACT standard is final. This commenter gave specific examples of

why this is of particular concern to the can manufacturing industry. 
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As a related matter, the commenter suggested that for cases where a section 112(d)

MACT standard has not been proposed by, for example, January 2002, the application

deadline for submittal of the Part 2 MACT application should be 12 months, rather than 6

months, after submittal of the Part 1 application. (IV-D-17)

Another commenter (IV-D-26) requested two changes regarding application

submittals to reduce burden on facilities and permitting authorities. The commenter

asked that EPA revise the rule to provide that the Part 2 application is due 12 months, not

6 months after the Part 1 MACT is submitted. The commenter noted that this would

move the deadline from November 15, 2002 ro May 15, 2003. This change would be

necessary for MACT rules for which it is unlikely that promulgation will occur by May

15, 2002 due to delays created by lawsuits. The commenter noted that a Part 2

application is a substantial effort. Due to the delay, facilities would have to submit the

Part 2 application, a costly and time consuming effort that would be moot as soon as the

112(d) rule is completed. The commenter believed that extending the Part 2 application

submittal date would reduce the risk of burdening facilities and permitting authorities

while giving EPA more time to promulgate the 112(d) standards.

The commenter (IV-D-26) also requested that the final rule state that a Part 1

notification is unnecessary if EPA proposes a MACT standard before the statutory

hammer date of May 15, 2002. The commenter believed this approach would eliminate

the need for fruitless paperwork to be developed.

The commenter (IV-D-26) also proposed an alternative to changing the rules,

which would be to incorporate by reference or repeat the terms of any settlement

extending the schedule for 112(d) promulgation and a schedule for extensions of the

section 112(j) applications. The commenter explained that this approach would be

preferable if there will have to be a staggered schedule in which proposals cannot all be

published by May 15, 2002, or completed before May 15, 2003. (the date an additional 6-

month extension for Part II applications would provide) 

The commenter explained that the publication of either approach in a final rule

would need to occur before May 15, 2002.

Still another commenter (IV-D-27) argued for an 18-month period between Parts 1

and 2 applications to alleviate the burden faced by sources and permitting authorities.

Response:

We appreciate the commenters’ concerns, and we are making every effort to

promulgate the remaining MACT standards as soon as possible. However, we note that

the previous permit application extensions for the 4- and 7-year MACT rules were
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54

established because the standards were to be issued very shortly after the deadline. This

is not the situation now, with a significant number of the 10-year MACTstandards not

scheduled for promulgation until well after the deadline. The intent of the 2-part section

112(j) application process which we proposed was to alleviate unnecessary burdens by

deferring the collection of the more detailed information necessary for a complete caseby-case MACT application until after the “hammer” date had passed. However, it is

now apparent that the process for submission of section 112(j) applications as we

proposed it will not significantly alleviate the burden on sources and permitting

authorities.

Section 112(j) of the CAA was designed to be a “backstop” to our failure to issue

MACT standards. Clearly, we will not complete promulgation of all scheduled MACT

standards in the 10-year bin by the section 112(j) deadline of May 15, 2002, and in fact,

we will miss the schedule for numerous source categories. The task to develop MACT

standards on schedule to cover all the listed source categories has been enormous, and

our past schedules projecting issuance by the hammer date have proved to be unduly

optimistic. However, we are still committed to completing all MACT standards in as

timely a manner as practicable. Although numerous standards will be late, we currently

anticipate that many of the remaining standards in the 10-year bin will be proposed

before the hammer date, and that all standards in that bin will be promulgated before any

case-by-case MACT determinations would be required under the 24 month timetable for

permit issuance which we proposed (consisting of 6 months for submission of the Part 2

application and 18 additional months for action by the permitting authority).

We agree with the commenters that a process in which the source must gather

detailed information and then prepare and submit a Part 2 title V permit application and

the permitting authorities must then review each of the submitted applications and

prepare for issuance of a case-by-case MACT determination represents an unnecessary

burden if all MACT standards will be promulgated before any actual permits will be

issued. We conclude that such resources would be better spent preparing for and

implementing the MACT standards when they are promulgated. Thus, we have decided

to revise the proposed rule to extend the amount of time between the Part 1 and Part 2

section 112(j) application to 24 months which coincides with the time period in which we

expect to promulgate MACT standards for the remaining categories.

As the preamble to our proposal makes clear, we based our proposal to provide a

6 month period between the Part 1 and Part 2 applications in part on the concept that

every applicant would automatically be given the maximum extension to supplement an

incomplete application which is explicitly provided for by CAA section 112(j)(4). 

However, as one commenter noted, there is another provision in the statute which may be

construed as providing authority to establish an incremental process for the submission

of section 112(j) applications. The hammer provision in section 112(j)(2) itself

establishes the requirement to submit permit applications “beginning 18 months after”

the statutory date for promulgation of a standard. Reading this provision in context, we
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believe that the statute can be reasonably construed as authorizing us to provide a period

of time after the hammer date in which the information necessary for a fully informative

section 112(j) application can be compiled. This alternate construction also makes more

practical sense, because it retains the statutory process in which the permit authority can

determine whether or not an application is complete and provides the applicant the

extension of up to 6 months contemplated by section 112(j)(4). This assures that the time

required to supplement an incomplete application will not be deducted from the time in

which the permitting authority must complete its work.

While we recognize that compilation of the information needed for a Part 2

application is not likely to take 24 months, we are nevertheless reluctant to mandate that

significant resources be devoted to an exercise which will ultimately be futile and

unproductive. The burden of compiling a Part 2 application for simple sources

containing only a small number of emission points may not be particularly onerous, but

the burden on more complex sources containing numerous sources and emission points

could be significant. The sheer number of affected sources that would have to submit a

Part 2 application by November 15, 2002, under the rule as proposed is very large,

estimated at over 80,000. Such an exercise would also needlessly divert resources

needed for other critical tasks at already overworked permitting authorities. We do not

believe such an outcome was envisioned or intended by the drafters of section 112(j),

particularly in the circumstance where the Federal MACT standards will actually be

issued prior to the deadline for issuance of the case-by-case MACT determinations by the

permitting authorities.

Accordingly, we have decided to revise our proposal to provide for a 24 month

period between submission of the Part 1 application and submission of the Part 2

application. The 18 month period for issuance of the permit after receipt of a complete

application which is provided by the current section 112(j) rule and by section 503(c) of

title V will be retained. We are also restoring the statutory process in which the

permitting authority may review the application for completeness and grant an extension

of up to 6 months to remedy any deficiencies.

We received no adverse comment on requiring that the first portion (Part 1) of the

section 112(j) application be due on the hammer date. We think that this is the minimum

required by the statute. The Part 1 application is very short and simple, and we believe

the burden is minimal. The Part 1 application will also help permitting authorities to

identify sources potentially subject to the upcoming MACT standards. Sources must note

that our decision to extend the time between the Part 1 and Part 2 applications is no

excuse for not submitting a Part 1 application if the source can reasonably determine it is

in one of the source categories or subcategories subject to the section 112(j)

requirements. Failure to meet the section 112(j) requirements, including failure to make

a timely Part 1 application, can lead to enforcement action. If a source is unsure about

its applicability, it should submit a Part 1 application requesting an applicability
3-112(j) Com ments

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determination to the permitting authority, which will then make a determination of MACT

applicability. 

3.2.3 Avoid Triggering Section 112(j)

Comment:

A few commenters strongly encouraged EPA to continue striving to meet all the

section 112(d) or (h) deadlines so that the provisions of section 112(j) might never be

necessary. (IV-D-06, 11, 13) A few commenters urged EPA to meet the deadlines for

promulgating the 112(d) standards due in 2002 for various combustion sources. (IV-D06, 11) One commenter emphasized that this is the most efficient use of EPA resources

with the greatest public benefit, and that avoiding use of section 112(j) should be a top

Agency priority. (IV-D-13) One commenter hoped that these provisions might never be

implemented, but expressed concerns about their implementation if they are necessary.

(IV-D-03)

Response:

As we stated above, we appreciate the commenters’ concern, and we are making

every effort to meet the statutory deadlines so that section 112(j) is not triggered. 

Nevertheless, at this point, it will not be feasible for us to complete all the MACT

standards by the section 112(j) deadline. For an update on the status of section 112

rulemakings, see our website at http://www.epa.gov/ttn/atw/eparules.html.

3.3 Comments on §63.50, Applicability

3.3.1 Clarification of General Applicability [§63.50(a)]

Comment:

One commenter supported the proposed change to clarify that MACT standards

will apply only to the affected sources within a subject category or subcategory. The

commenter also recommended that EPA specify in each MACT standard’s applicability

statement those subcategories of equipment or processes that are not covered by the

standard. This would help facilities clearly define their compliance obligations. The

commenter believed that discussion of such applicability issues in the preamble is not

adequate, and failure to include this information in regulations could result in

inappropriate application of the rule by permitting authorities. (IV-D-22) 
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Response:

We appreciate the commenter’s support. We agree also that each standard should

be as specific and clear as possible as to what is covered. We do not agree that listing

everything at a source that is not covered is necessary. Individual MACT standards may

specify what is not covered, if appropriate. If there is a question regarding what is

covered, it should be raised during the public comment period or with the permitting

authority.

3.3.2 Imposition of More Stringent Requirements Than MACT

[§63.50(b)]

Comment:

One commenter stated that EPA should clarify that State or local agencies can

impose more stringent requirements than MACT only as a matter of State or local law,

not as a matter of federal law. The commenter cited language in the Act that specifies

that section 112(j) limitations be equivalent to those that would be in effect under a

section 112(d) standard. The commenter maintained that EPA’s proposed language

exceeds the Agency’s statutory authority, because it does not reflect this explicit

limitation. The commenter proposed adding the phrase “as a matter of State or local law”

to §63.50(b) to explicitly clarify that more stringent limitations are permitted only under

State or local law, not federal law. (IV-D-03) 

Response:

We agree with the commenter that the statute specifies that section 112(j)

limitations must be equivalent to those that would be in effect under a section 112(d)

standard. We also agree with the commenter and the petitioners that States can be more

stringent only as a matter of State law. Although we believe that the ability of a State to

establish a more stringent emission limitation was already implicit in the promulgated

and proposed regulations, we have revised proposed §63.50(b) by adding the phrase “as

a matter of State or local law” to read “Nothing in §§63.50 through 63.56 shall prevent

a State or local regulatory agency from imposing more stringent requirements as a

matter of State or local law than those contained in these subsections.”

If we fail to promulgate a 112(d) standard by the statutory deadline, the State or

local permitting authority must make a case-by-case determination of MACT. The

revision to §63.50(b) does not change this statutory requirement. As a matter of State

law, the emission limitation or standard may be more stringent than the MACT. In such

a case, the portion of the limitation or standard that is more stringent than MACT would

only be enforceable by the State. However, it should be noted that the permitting
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authority defines MACT in the absence of a 112(d) standard. Until a section 112(d)

standard is established, one cannot determine whether case-by-case MACT is more

stringent than the 112(d) standard.

3.4 Comments on §63.51, Definitions

3.4.1 Affected Source

Comment:

Two commenters believed EPA still needed to clarify in the definition of affected

source that sources that do not emit HAP are not part of the affected source. For

example, many conveying system transfer points and other manufacturing elements at a

facility are totally enclosed, do not emit HAP, and should not be included in the affected

source. (IV-D-02, 14)

Response:

We disagree with the commenters’ assessment that the definition of “affected

source” requires further revision. The issue about sources that do not emit HAP will be

addressed in each NESHAP, which must clearly define the affected source. Each

NESHAP should make clear what parts of the facility have reporting, recordkeeping,

monitoring, or other compliance requirements. Not all of the processes in the affected

source will necessarily have requirements; however it may not always be technically

feasible or practical to separate sources that do not emit HAP from the affected source.

3.5 Comments on §63.52, Approval Process

3.5.1 Relationship of Regulations under

Sections 112(g), (j), (d), and (h) [§63.52(a)(3) and 63.56(c)(1)]

Comment:

Two commenters supported the proposed approach for addressing sequential

MACT determinations under different sections of the Act through application of the

“substantially as effective” test. (IV-D-12, 25) One commenter stated that this

clarification to case-by-case MACT determinations constitutes a commonsense, workable

approach to handling transitions from one type of MACT limitation to another. The

commenter believed that without such an approach, permitting authorities might impose

new MACT requirements that would be burdensome, yet achieve no environmental
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benefits. Requiring a source to make capital expenditures to meet a new MACT standard

when the existing MACT determination is “substantially as effective” in controlling HAP

would be unreasonable. (IV-D-25)

Response:

We appreciate the commenters’ support.

Comment:

One commenter maintained that State determinations of what constitutes

“substantially as effective” requirements when integrating case-by case MACT

limitations with section 112(d) MACT standards should be driven by practical

considerations of compliance and emissions reduction rather than “regulatory legalisms

and forms.” (IV-D-24)

Response:

We agree with the commenter. Our intent in proposing the ‘substantially as

effective” test is to do exactly what the commenter suggests: provide a means to avoid

“...substantial additional burdens...imposed...regardless of the significance of the

resultant impact on emission reductions.” See the detailed discussion of this test in the

proposal preamble at 16339. The proposal preamble also described the results of

implementing the substantially as effective test using several examples on pages 16340-1.

“By evaluating the actual effect from both sets of requirements, the decision is focused on

the practical benefit to the environment rather than an exercise in paperwork.” 

Comment:

One commenter maintained that compliance with a case-by-case MACT

determination under section 112(g) should constitute compliance with any subsequent

case-by-case requirement under section 112(j). This commenter stated that requiring a

section 112(j) determination subsequent to a section 112(g) determination is overly

burdensome and is unlikely to achieve any environmental benefits. The commenter said

that EPA’s proposed approach of determining whether a prior section 112(g) emission

limitation is “substantially as effective” as a section 112(j) requirement will not

significantly alleviate that burden and will still require considerable resources from

sources. (IV-D-13)
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Response:

We disagree with the commenter’s evaluation that applying the “substantially as

effective” test will not alleviate burden on sources. Again, see our extensive discussion

of this policy in the proposal preamble at 16339. Also, case-by-case MACT

determinations under 112(g) are only applicable to major source construction or

reconstruction and require compliance with new source MACT. Sources under section

112(g) may not be the same as sources under section 112(j). Any source subject to

subsequent standards pursuant to sections 112(j) or (d) or (h) will likely be considered an

existing source under those standards. 

We believe that in most, if not all, situations section 112(g) determinations should

suffice for section 112(j) determinations. The case-by-case process should be replicable

and when done by the same permitting authority should lead to essentially the same

results, unless new information has come to light after a section 112(g) determination. 

The amendments provide that if a permitting authority concludes that the section 112(g)

determination is substantially as effective as what the permitting authority would have

established under section 112(j), then the permit would be revised to simply reflect that

fact and retain the section 112(g) requirements to satisfy section 112(j). 

Comment:

One commenter stated that the final rule should more vigorously encourage States

to adopt prior section 112(g) or (j) MACT determinations. This commenter

recommended that the final rule adopt the rebuttable presumption that the first MACT

determination is “substantially as effective” as any subsequent MACT determination in

order to protect sources from multiple MACT determinations. The commenter believed

that this would be consistent with the intent of the proposed changes, and that it would be

consistent with other rebuttable presumptions in the proposal (such as the assumption that

the new affected source is the entire affected source unless a different approach is

justified). (IV-D-17)

Response:

We disagree with the commenter. While it may be that the first MACT is

substantially as effective as any subsequent MACT determinations, it is possible to have

better information at a later date and important “...to afford the permitting authority

some discretion to consider the substantive adequacy of section 112(g) requirements

when it makes a subsequent decision concerning...section 112(j)” and the same is true for

subsequent 112(d) or (h) standards. The rule has not been changed in this regard.
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Comment:

One commenter questioned the section 112(j) permit application process for

sources with a pending permit application under section 112(g). The commenter

interpreted §§63.52(a) (3) and (b) (2) to require that the source wait for the section 112(g)

permit to be issued, then apply for a change to the permit to incorporate section 112(j)

requirements. The commenter was concerned about the situation where a MACT

standard is promulgated before issuance of the source’s 112(g) permit, but after the

section 112(j) deadline. The commenter recommended that a provision be added to

specify that in such a case, the source could forgo the section 112(j) application and

request a determination of whether the section 112(g) requirements are “substantially as

effective as” the promulgated MACT standard. (IV-D-03)

Response:

The commenter is correct. Pending section 112(g) applications must be completed

and then the owner or operator must apply for a section 112(j) permit within 30 days

after the section 112(g) permit is issued. However, the permitting authority may deem the

section 112(g) requirements substantially as effective as what section 112(j) would

require. In this case, the permit would be revised to reflect that the section 112(j)

requirements are the same as the section 112(g) requirements. 

Comment:

A few commenters maintained that EPA had not clearly specified what actions the

permitting agency should take when a new major source is constructed or reconstructed

after the section 112(j) deadline and both sections 112(g) and 112(j) apply. These

commenters stated that a facility should be allowed to submit a single application to meet

both sets of requirements, and that the section 112(j) regulation should clearly outline the

permitting procedure for this situation. (IV-D-04, 18)

Response:

Section 112(j) would apply only to major sources in source categories listed

pursuant to section 112(c). Section 112(g) applies to any major source with potential to

emit HAP. Therefore, section 112(g) does not necessarily apply to the same sources that

would be subject to case-by-case determinations under section 112(j). However, in the

instances where sections 112(g) and 112(j) both apply, the source owner/operator would

still need to submit separate permit applications to satisfy the requirements of each

program. Nothing in section 112(j) allows it to be waived when an application pursuant

to section 112(g) has been submitted.
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We believe the number of occasions where both applications would need to be

submitted will be limited. We do not believe these requirements would be burdensome. 

In the instances where a source is required to submit both applications, the section

112(g) application should contain most of the information necessary for a Part 2 section

112(j) permit application. However, we encourage the permitting authority to streamline

the specific permit application forms for sections 112(g) and 112(j) where possible to

reduce any potential burden on source owner/operators and on permitting authority staff. 

Section 112(j) requirements can be deemed substantially as effective as the section 112(g)

requirements. 

3.5.2 Permit Application Process [§63.52(a) and (b)]

Comment:

A few commenters supported the proposed permit application procedures, which

consist of a Part 1 and Part 2 application. (IV-D-12, 18, 25)

Response:

We appreciate the commenters’ support.

3.5.3 Timing of Title V Permit Applications [§63.52(a) and (b)]

Comment:

A few commenters expressed concern about the requirement for permitting

authorities to notify affected sources within 120 days of the section 112(j) deadline. (IVD-04, 18, 20) These commenters noted that States do not always have up-to-date

information on sources and that 120 days is not sufficient time for such notifications.

Furthermore, these commenters recommended that this requirement be deleted because

States may choose to identify and notify affected sources but should not be required to do

so. A few commenters recommended that the final rule specify that owners or operators

of affected sources must submit a title V permit application whether or not they receive

notification. (IV-D-04, 20) One commenter believed that State notification, if required,

would be most appropriate before the Part 1 MACT deadline; thus, EPA should give

States sufficient notice of which MACT standards are unlikely to be promulgated by the

deadline. This commenter also suggested that §63.52(a)(2) should specify whether a Part

1 or Part 1 and 2 application is required after notification by the State. Finally, this

commenter stated that 30 days may be insufficient for facilities to submit a Part 1 and

Part 2 application. (IV-D-18)
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Response:

We agree with the commenters that it is the responsibility of the affected source to

submit a title V permit application regardless of notification if it can reasonably

determine that it falls within a source category for which a standard has not been

promulgated by the section 112(j) deadline. We believe in most instances that the

owner/operator will be able to reasonably determine whether the source is in the

category or subcategory subject to section 112(j), generally from the provisions in the

proposal rule or on EPA’s Air Toxic’s Website, http://www.epa.gov/ttn/atw/. If an

owner/operator is unable to make this determination, they may, at their discretion,

contact the permitting authority for assistance in making the determination or submit a

Part 1 application with an applicability determination request. If there is doubt, the

owner or operator must submit the Part 1 application. Most MACT standards will be

proposed by the section 112(j) deadline of May 15, 2002, and applicability criteria will

be specified in those proposals. In addition, we are posting applicability criteria on

EPA’s Air Toxics Website for all source categories for which MACT standards have not

yet been proposed (see www.epa.gov/ttn/atw/eparules.html). The EPA project leads may

also be directly contacted for additional information. Thus, owners or operators should

know for all source categories whether or not their sources will be subject to the section

112(j) requirements. Therefore, we are retaining §63.52(a)(1) as proposed, which

requires an owner or operator to submit an application for a title V permit or permit

revision if the owner or operator can reasonably determine that one or more sources at

the major source belong in the category or subcategory subject to section 112(j). The

obligation is on the source owner or operator to submit the application. Failure to

submit a Part 1 application when it can reasonably be determined the source is in an

applicable source category would be considered a violation. 

Moreover, we also agree with the commenters that 120 days may not be sufficient

time to notify owner or operators of affected sources subject to section 112(j) if those

sources did not submit a title V permit application because they could not reasonably

determine if they were part of a source category on which the section 112(j) “hammer”

fell. As the commenter pointed out, State agencies may not necessarily already have this

information and would not be able to identify each and every affected source within 120

days, especially those in source categories that contain tens of thousands of sources. We

do not want to create an opportunity to potentially circumvent the requirements of the

rule when the State fails to notify the source owner/operator by a specified time because

it does not have adequate information. Therefore, in the final rule amendments we have

removed from proposed §63.52(a)(2) the requirement that the permitting authority must

notify the source owner or operator within 120 days of the section 112(j) deadline. States

may still choose to identify and notify affected sources and we encourage them to do so

when they have the available information.
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The Part 1 application is intentionally brief so that completing it will not be a

complicated, burdensome requirement. If there are isolated instances where a Part 1

application is erroneously submitted where none is required, it would be the

responsibility of the permitting authority to notify the owner or operator that the source

is not in a category or subcategory subject to section 112(j). In addition, the permitting

authorities have the obligation to determine MACT applicability if requested in a Part 1

application.

Comment:

A few commenters supported the 120-day notification period for permitting

authorities to notify sources that do not submit an application by the section 112(j)

deadline. These commenters believed that this is an adequate period for permitting

authorities to act, and should not be extended, as a longer period might result in lingering

questions about applicability. (IV-D-12, 25)

Response:

See previous response. If there are any questions about applicability, the source

should contact the permitting authority prior to the section 112(j) deadline or submit a

Part 1 application with a request for applicability determination.

3.5.4 MACT Applications for Area Sources That Become Major

[§63.52(b)(3) and (4)]

Comment:

One commenter suggested that §63.52(b)(3) should be revised to more clearly

distinguish its provisions from those in §63.52(b)(1). The commenter stated that an area

source that becomes major through the installation of equipment [as discussed in

§63.52(b)(1)] would also require a relaxation in its emission limitation to allow the

installation to occur. Thus, the commenter proposed that §63.52(b)(3) be revised to say

“...due to a modification or solely to a relaxation in any federally enforceable emission

limitation.” (IV-D-03)

Response:

 Section 63.52(b)(3) specifically refers to a relaxation of a federally enforceable

emission limitations on potential to emit, and §63.52(b)(1) does not. Thus, we believe

that the section is clear as written, and it has not been changed.
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Comment:

One commenter supported EPA’s retention of the 6-month timeline established in

§63.52(b)(4) for submitting a Part 1 MACT application for sources who become subject

to a MACT standard due to the establishment of a lesser quantity emissions rate. The

commenter believed that implementing a 30-day timeline would be too short, because

nonmajor sources operate under the assumption that they will not be subject to a MACT

standard. When a lesser quantity emissions rate is established, they become subject to a

standard through no action of their own. Unless these sources were already major for a

criteria pollutant, they would not have submitted a title V permit application, and could

therefore be required to prepare the permit and the MACT application in a short time

period. For all these reasons, the commenter urged EPA to give such sources 6 months to

submit a Part 1 MACT application. (IV-D-03)

Response:

We appreciate the commenter’s support.

3.5.5 Compliance Extensions [§63.52(d)(1)]

Comment:

A few commenters observed that the section 112(j) regulation identified a permit

as the only mechanism for granting a compliance extension. However, some agencies use

compliance or consent agreements to grant MACT compliance extensions; therefore, the

commenters recommended that §63.52(d)(1) be revised to include such written

agreements as valid mechanisms for compliance extensions. (IV-D-04, 18).

Response:

Section 112(i)(3)(B) of the Act states that the title V permit is the only mechanism

for compliance extensions; thus, we have no authority to change the rule as

recommended by the commenters.

The paragraph referred to by the commenters was amended, and compliance

extension provisions are no longer contained within the section 112(j) regulation.

Instead, these provisions are all found in §63.6 of the General Provisions. 
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3.5.6 Permit Application Review [§63.52(e)(2)(ii)]

Comment:

One commenter disagreed with the requirement to submit a Part 2 MACT

application within 6 months after receiving a negative determination that its section

112(g) requirements are substantially as effective as what section 112(j) would require.

The commenter proposed that if a petition for review of a negative determination is filed,

the requirement to submit a Part 2 MACT application should be stayed until a court

decides the case, because it is unlikely that such a review would be complete within 6

months. (IV-D-03)

Response:

The section 112(j) requirements, including the requirement to submit a Part 2

MACT application, apply in this case. Section 63.52(e)(2)(ii) states that “A negative

determination under this section constitutes final action for purposes of judicial

review...” The rule has been revised to allow 24 months to submit a Part 2 application

after receiving a negative determination.

3.5.7 Enhanced Monitoring Requirements [§63.52(h)]

Comment:

One commenter stated that the preamble language that refers to “posting all

compliance reports on a publicly available bulletin board” (page 16336) as an example of

what §63.52(h) requires, should be retracted in the preamble to the final rule. The

commenter maintained that this statement exceeds EPA’s authority to specify such

requirements. (IV-D-03)

Response:

We included the statement in the preamble that the commenter referred to as an 

example of a way to ensure that States incorporate monitoring, recordkeeping and

reporting mechanisms that comport with enhanced monitoring provisions. The rule does

not require that this specific suggestion be implemented. We do not believe the statement

exceeds our authority, nor is it necessary to retract the statement in the preamble to the

final rule.
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3.6 Comments on §63.53, Application Content for Case-by-Case

MACT Determinations

3.6.1 Content of MACT Application [§§63.53(a) and (b)]

Comment:

A few commenters supported the content specified in the proposed rule for each

portion of the application. (IV-D-12, 25) 

Response:

We appreciate the commenters’ support.

Comment:

One commenter recommended that the description of information required in the

Part 1 MACT application would be clearer if the word “sources” in §63.53(a)(3) was

replaced with “emission points.” The commenter also recommended revising

§63.53(b)(1)(iv) to specify the control technology in place for each “affected emission

point or group of affected emission points” instead of “each piece of equipment or

activity or source.” The commenter believed that EPA’s proposed language would result

in a burdensome requirement to list every single valve, flange or pump controlled by a

leak detection and repair program, instead of noting that there are valves, flanges and

pumps controlled by such a program. Finally, this commenter recommended that

§63.53(b)(2)(ii) be changed to refer to control technologies that “would” be applied to

meet the emission limitation rather than “shall” be applied, since the source completing

the MACT application is not the final judge of whether the proposed controls will be

acceptable. (IV-D-03)

Response:

We agree that the changes recommended by the commenter clarify, and are

consistent with, the provisions of the rule, so we have revised §§63.53(a)(3), (b)(1)(iv),

and (b)(2)(ii) as the commenter suggested.

Comment:

Representatives of the State and Territorial Air Pollution Program Administrators

(STAPPA) and the Association of Local Air Pollution Control Officials (ALAPCO)

commented that most agencies would want to receive the information listed in
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§63.53(b)(2) and wondered why EPA had designated it as an optional part of the Part 2

MACT application. (IV-D-04)

Response:

The information listed in §63.53(b)(2) includes information and analyses about

appropriate emission limitations and control technologies to meet those limitations.

While the source owner/operator may choose to submit this information, it is not their

responsibility to conduct the research and analysis necessary to make MACT

determinations. This responsibility resides with the State or other designated permitting

authority. For this reason, it is appropriate that the information listed in this paragraph

be an optional part of the Part 2 MACT application. 

3.7 Comments on §63.54, Preconstruction Review Procedures

3.7.1 Preconstruction Review Plan

Comment:

One commenter supported the provisions established in §63.54(a)(2), which allow

an owner/operator to seek a Notice of MACT approval before constructing a source. The

commenter requested assurance that such an approval would ensure that a new source

meets MACT, and would not be subject to additional requirements subsequent to

construction. The commenter stated that this was particularly important because MACT

limitations will be part of a title V permit, which is issued after construction. The

commenter believed that a MACT determination that took place only during the title V

permit process could result in a facility being subject to more stringent limitations than it

was built to meet. (IV-D-01)

Response:

We appreciate the commenter’s support, but believe that the concern expressed is

unwarranted. The substance of these provisions was not proposed to be amended; only a

minor change in phraseology from “emission unit” to “affected source.” 
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3.8 Comments on §63.55, Case-by-case MACT Determinations 

3.8.1 Reference to National Database [§63.55(c)]

Comment:

One commenter stated that the section 112(j) regulation mentions a “National Data

Base” at §63.55(c) and the section 112(g) regulation mentions a MACT data base at

§63.43(m). The commenter requested that these statements be clarified. (IV-D-18)

Response:

The title of paragraph 63.55(b) (not §63.55(c) as the commenter stated) has been

revised from “Reporting to national database” to “Reporting to EPA” to address the

commenter’s concern and more accurately reflect the contents of the paragraph.

3.9 Comments on §63.56, Case-by-Case Determination After

MACT Promulgated

3.9.1 Prohibition of Backsliding [§63.56(c)(2)]

Comment:

Several commenters disagreed with EPA’s proposed prohibition of backsliding,

which prevents a State from adopting any section 112(d) emission limitations that are

less stringent than emission controls already required by the permitting authority [such as

those adopted under section 112(j) or 112(g)]. (IV-D-01, 5, 10, 17, 24) The commenters

maintained that this policy is inconsistent with the plain language of the Act and prior

EPA policy. The commenters stated that this policy should not be adopted. Instead, one

commenter proposed that the rule be revised to require States to revise permits to

conform to MACT standards issued after other emission limitations have been adopted. 

(IV-D-05) This commenter believed that the prohibition on backsliding would create

unnecessary burden and uncertainty because permitting authorities and sources would

have to spend significant time and resources to determine when a MACT standard is less

stringent. One commenter maintained that implementing the anti-backsliding policy

would result in uneven requirements for similar industries in different States and would

also require Federal enforcement of regulations that were not subject to national review. 

(IV-D-01)
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Response:

The current section 112(j) rule does not include any prohibition on backsliding,

and the current section 63.56(c) allows the permitting authority to exercise its discretion

in determining whether or not to retain more stringent provisions from a prior section

112(j) MACT determination in the operating permit. Similarly, the rule governing caseby-case MACT determinations under section 112(g) does not contain any prohibition on

backsliding, and section 63.44(c) provides that the permitting authority may exercise its

discretion in deciding whether or not to retain more stringent provisions from a section

112(g) case-by-case MACT determination as applicable requirements in the operating

permit.

After considering the concerns raised by the commenters, we have decided that it

is best to retain this basic policy in the amended section 112(j) rule. As reflected by the

provisions in the existing section 112(j) rule, we do not agree with the argument by some

commenters that the statute requires the permitting authority to backslide, but we do

believe that the decision whether or not to retain any more stringent provisions of a

section 112(j) determination as applicable legal requirements following issuance of a

section 112(d) standard should be committed to the discretion of the permitting authority

that made the case-by-case determination in the first place. Accordingly, we have

amended the proposed language to delete the prohibition on backsliding and to afford the

permitting authority the discretion to determine whether or not backsliding is

appropriate. The revisions in the language we proposed make it essentially identical to

the language we adopted previously for section 112(g) determinations.

3.10 Comments on 112(j) Guidance Document

3.10.1 No Case-by-Case MACT

Comment:

One commenter requested that EPA emphasize its authority to state in section

112(j) guidance that States should not start case-by-case 112(j) MACT determinations

through title V permits because such costly determinations would be superseded by a

national MACT standard. (IV-D-24)

Response:

Although the MACT standards will come out eventually, section 112(j) exists to put

MACT provisions in place if standards are not issued in a timely manner. Once section

112(j) applies, permitting authorities have a non-discretionary statutory duty to develop
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case-by-case MACT until a standard is actually issued. The EPA has no authority to

nullify the statutory requirements. We recognize the burden and scheduling implications

of the section 112(j) process and hope to avoid or minimize this whenever possible. For

an update on the progress of regulations, see our website at

http://www.epa.gov/ttn/atw/eparules.html.

3.10.2 Separate Comment Process for Guidance Document

Comment:

One commenter was unaware of the request for comments on the section 112(j)

guidance document until late in the comment period, because this request was not

highlighted in the beginning of the preamble. This commenter suggested that requests for

comments on such documents be made separately from the proposed rule changes in

order to ensure that the public is adequately notified and has time to develop comments.

The commenter noted that they would be unable to submit comments by the May 22,

2001 deadline. (IV-D-21) 

Similarly, another commenter stated that the guidance document is an important

part of the section 112(j) process; therefore, any further information or changes proposed

to the guidance should undergo a public notice and comment process. (IV-D-03)

Response:

We believe that the public was given adequate notice and opportunity to comment

on the draft guidance document. There is no requirement under the Administrative

Procedures Act for public comment on guidance, but we chose to provide that

opportunity in this proposed rulemaking.

3.10.3 Guidance Document on EPA Website

Comment:

One commenter requested that EPA remove the old section 112(j) guidance

document from the Unified Air Toxics Website and replace it with the updated guidance

referenced in this proposal. (IV-D-10)

Response:

This has been done.
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3.10.4 MACT Database

Comment:

A few commenters stated that the MACT database referred to in the section 112(j)

Guidance Document is not functional and therefore all references to it should be deleted.

The commenters further noted that some states do provide information to EPA for posting

on the “112(g) MACT Determination State Permit Engineers Clearinghouse” on EPA’s

website, and that providing this information is optional. The commenters requested that

if this is what the guidelines refer to, they should be revised to not mistakenly refer to it

as a database. (IV-D-04, 18)

Response:

The commenters are correct, and we have revised the guidance document

accordingly. The MACT database has not been fully developed.

3.10.5 Compliance Provisions [Section 2.2]

Comment:

One commenter stated that in section 2.2, EPA notes that short term emission

limits are appropriate when operating parameters cannot be imposed. The commenter

suggested that under these circumstances, rolling averages are more appropriate than

absolute pound per hour limits, because rolling averages consider all operating variables

over the averaging time, are easier to calculate, and are more accurate. Furthermore,

measurement errors are magnified in a short-term emission limit, but are less significant

in a rolling average. The commenter recommended that rolling averages be considered

the preferred alternative when operating parameters cannot be imposed. (IV-D-03) 

Response:

The decision whether to require rolling averages rather than other types of

emission limits would be made in individual MACT determinations, as each MACT

determination will include requirements for compliance demonstration, emission

limitations, performance testing, and work practice standards. In many cases short-term

limits are preferred because compliance can be determined contemporaneously. A short-
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term limit is easier to enforce and provides the source with immediate feedback. Rolling

averages have been and will be used where appropriate. 

3.10.6 Similar Emission Units [Section 3.4]

Comment:

One commenter agreed with the EPA that the two questions laid out in section 3.4

should both be answered in the affirmative for emission units to be considered similar,

and suggested that this be clarified in the final guidelines. (IV-D-03)

Response:

We appreciate the commenter’s support.
74
4 - Other Comments

75

Chapter 4 - Other Comments

4.1 Overview

Other comments on the General Provisions and section 112(j) generally concerned

issues that affect MACT standards more generally, such as the definition of 

“source”among different regulations, the basis for the MACT floor, the interaction

between MACT standards and the title V permit program, and other EPA policies. 

4.2 Miscellaneous Comments

4.2.1 Definition of Source Among Various Air Regulations

Comment:

One commenter suggested that EPA clarify the definition of source among the

various regulations. The commenter noted that the New Source Performance Standards

(NSPS) and Prevention of Significant Deterioration (PSD) regulations both initially

considered a discrete piece of equipment or individual process. In recent regulations,

however, the term source has come to mean all of the equipment at one or more plant

properties. The commenter believed that EPA’s revision of the definition of source had

expanded applicability and regulatory requirements, which is confusing and burdensome. 

(IV-D-01)

Response:

While we appreciate the commenter’s concerns, the different definitions of

“source”are necessitated by the different statutory requirements that exist for NSPS,

PSD, and MACT programs. Applicability is not determined in the same way under these

different programs. 

Under the MACT program, a “major source” is defined as any stationary source

or group of stationary sources located within a contiguous area and under common

control that emits or has the potential to emit considering controls, in the aggregate, 10

tons per year or more of any HAP or 25 tons per year or more of any combination of

HAP.

An “area source” under the MACT program is any source that is not a major

source.
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76

The term “stationary source” is defined the same under both the NSPS and MACT

programs as any building, structure, facility, or installation which emits or may emit any

air pollutant. In the NSPS program, a stationary source has been further termed an

“affected facility” and in the MACT program it is referred to as an “affected source.”

In the NSPS and MACT programs, the affected facility or affected source is

decided for each rule - this may be the entire plant site or part of the plant site, but has

often been defined at less than the plant site level.

In the PSD program, the definition of major stationary source is a stationary

source in a given 2-digit Standard Industrial Classification (SIC) code, on contiguous

and adjacent property under common control. Once subject to PSD for a particular

pollutant, the permitting authority makes a case-by-case determination regarding the

emission limitation that reflects BACT. These emission limitations to meet PSD

requirements have sometimes been applied to one or more discrete emission units. 

However, some of the PSD limits are plantwide. In addition, monitoring, recordkeeping,

and reporting requirements may be established for one, several, or many emission units.

We have recently clarified in the proposal preamble the meaning of “contiguous”

for the MACT program to improve a source owner/operator’s understanding of when

sources that are separated by a public right of way are part of the same affected source.

Comment:

One commenter requested that EPA specifically identify in each NESHAP which

subcategories are not affected by the standards. The commenter explained that the

Printing and Publishing NESHAP did not cover screen printing or offset lithographic

operations. The commenter maintained that these processes should have been clearly

exempt from the NESHAP, not just discussed in the preamble, as some permitting

authorities are inappropriately applying the standards to these operations. By including

the exemptions in the rule, it would be clear what the compliance obligations for the

facility are. Also, outreach materials for NESHAP should include which units are

covered and not covered. (IV-D-22)

Response:

Each NESHAP will specifically identify the source category and the affected

source to which the standard applies. As discussed in the proposal preamble at 16323/3:

“...for each future relevant standard...we will explicitly define the terms “affected

source” and “new affected source.” The use of two terms will clarify the applicability of

existing source MACT and determine where new source MACT should apply.”
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77

Listing or identifying everything to which a standard does not apply would be

practically impossible. Proposed rules should be read closely and obvious questions

regarding applicability and clarity should be raised during the public comment period.

In the case of the Printing and Publishing NESHAP discussed by the commenter,

these issues must be resolved with the permitting authority or elevating them to EPA.

4.2.2 Definition of Affected Source in MACT Standards

Comment:

One commenter encouraged EPA to adopt a policy of defining affected source

broadly in all MACT standards. This approach would allow emissions averaging across

all process units and emission points throughout the facility. (IV-D-24)

Response:

In general, we agree with the commenter about a broad definition of “affected

source,” and this has been adopted in the General Provisions’ definition of “affected

source.” As discussed in the proposal preamble at 16323, we proposed, as a general

matter, that the affected source will consist of all existing HAP-emitting equipment and

activities at a single contiguous site within a specific source category; however, it may be

appropriate under any individual NESHAP to consolidate, or subdivide, or distinguish

among affected sources in other ways; if so, additional rational must be provided for

doing so. 

When we do adopt a broader definition of affected source, we will still determine

the MACT floor for the entire affected source by evaluating emissions and the feasibility

of controls separately for particular types of “emission units” within the affected source. 

This approach can afford owners and operators the option of demonstrating separate

compliance by individual emission units within the affected source or by adopting more

flexible control strategies and demonstrating compliance for the affected source as a

whole. Moreover, a standard for a larger affected source may still be a composite of

sublimits or other elements expressly directed at particular types of equipment or

activities, for which compliance would be determined separately.

In light of this flexibility, we agreed with the industry petitioners that it would be

feasible to adopt a broader definition of affected source on a more consistent basis. 

Thus, we proposed to change the General Provisions to indicate that future MACT

standards will generally adopt a definition of affected source which consists of all

existing HAP-emitting equipment and activities which are at a single contiguous site and

are within a specific category or subcategory. We do not believe we are required to
4 - Other Comments

78

adopt this policy, but we agree with the industry petitioners that it will foster greater

predictability and consistency in regulatory outcomes.

We also proposed to permit a narrower definition of affected source in particular

future MACT standards when a broad definition will result in significant administrative,

practical, or implementation problems, and a narrower definition would resolve these

problems. For example, in some instances, the facilities within a category or

subcategory which must develop appropriate compliance strategies may consider a

broader definition of affected source to be confusing. In other instances, the facilities

may operate dissimilar equipment or processes which do not emit the same HAP or type

of HAP, and a broader definition will have little or no utility in promoting more flexible

or efficient control strategies. These examples are only illustrative and are not intended

to limit our discretion to adopt a narrower affected source definition in particular future

MACT standards. However, when we adopt a narrower definition of “affected source,”

we will identify the specific problems created by the broader definition and specify why a

narrower definition will resolve them.

We also proposed to develop and adopt a separate definition of “new affected

source” for each future MACT standard after evaluating facilities in the category or

subcategory according to eight factors. These eight factors are: (1) emission reduction

impacts of controlling individual sources versus groups of sources, (2) cost effectiveness

of controlling individual equipment, (3) flexibility to accommodate common control

strategies, (4) cost/benefits of emissions averaging, (5) incentives for pollution

prevention, (6) feasibility and cost of controlling processes that share common

equipment, (7) feasibility and cost of monitoring, and (8) other relevant factors. Under

this process, the definition of “new affected source” for a particular MACT standard

may be the same as “affected source” or it may differ. The factors which we deem most

important in this assessment will differ from standard to standard. When we deem it

appropriate based on our evaluation of the eight factors to establish a definition of “new

affected source” less inclusive than “affected source,” we will do so.

We did not receive any comments opposing the new definitions and procedures for

specifying the affected source and new affected source for future MACT standards. 

Accordingly, we have decided to adopt these definitions and procedures as proposed.

Each future MACT standard subject to these new procedures will explicitly define

“affected source” and “new affected source.” Any decision to adopt a narrower

definition of affected source or to adopt a definition of new affected source differing from

the definition of affected source will be explained in the individual standard.
4 - Other Comments

79

4.2.3 Surface Coating Regulations for Motor and Equipment

Manufacturers

Comment: 

One commenter urged EPA not to regulate HAP from coatings through two

separate source categories, one for metal parts and one for plastic parts. Instead, it would

be more appropriate and more technologically feasible for EPA to regulate these HAP

sources using subcategories within the category destinations, including one or more

subcategories for automotive applications, such as thermo plastic olefin (TPO) olefin

systems, lighting fixture coatings, and certain other automotive applications. The

commenter noted that vehicle equipment manufacturers often apply coatings to both

metal parts and plastic parts in the same space. It would be difficult to follow two sets of

requirements, especially when those rules are likely to develop different HAP limits and

different MACT for each application. The commenter believed that the section 114 data

are not accurate. The commenter further stated that even if the data were accurate, the

covered industries are so divergent that the average HAP limit from the top performers

would be technically infeasible for many automotive companies. The commenter urged

EPA to subcategorize adhesives, glues, and putties, as these are different types of

materials that would not be able to meet the same emission limits as paints. (IV-D-09)

Response:

The regulations discussed by the commenter will be proposed in a separate

Federal Register Notice. The commenter’s concerns should be articulated in comments

on that rulemaking.

4.2.4 MACT Floor Based on 94th percentile

Comment: 

One commenter disagreed with EPA’s decision to base the MACT floor on the

emission limitations achieved by the 94th percentile for each class of equipment. The

commenter characterized this policy as an arbitrary reinterpretation of the statutory

requirement that the MACT floor be based on the average emission limitation achieved

by the best performing 12 percent of the existing sources. The commenter preferred that

MACT emission limits be based on the technology achieved by the median performer. 

(IV-D-01)
4 - Other Comments

80

Response:

The MACT floor policy was not discussed or proposed to be changed in these

amendments. We disagree with the commenter’s assessment of the policy. We have

determined that “average” means any measure of central tendency, whether it be the

arithmetic mean, median, or mode, or some other measure base on the best measure

decided for determining the central tendency of a data set. For further information, see

our discussion of this policy at 59 FR 29196 on June 6, 1994.

4.2.5 Enforcing More Stringent State NESHAP through Title V

Comment:

If a State promulgates a NESHAP that is more restrictive than the federal

regulations, the provisions of that NESHAP should not be included in a Title V permit. 

The commenter believed this would create an uneven playing field for similar industries

in different states. (IV-D-01)

Response:

State or local agencies may establish emission limitations more stringent than

those promulgated under 112(d), a process which has and continues to be the prerogative

of State and local agencies. This prerogative is codified in §63.12(a)(1). In such a case,

the portion of the limitation or standard that is more stringent than MACT would only be

enforceable by the State. However, the portion of the emission limitation required under

112(d) would still be an applicable requirement under §70.2 that must be included in the

title V permit according to §70.1(b).

4.2.6 Applicability of NESHAP to Minor Sources

Comment:

One commenter believed that many permitting authorities were incorrectly

interpreting the applicability of NESHAP to minor sources (either true minor sources or

minor sources collocated at major sources) and requested EPA clarification on this issue. 

The commenter believed that each affected source, as identified in the NESHAP, must be

major itself to be subject to the NESHAP. Minor HAP sources or minor HAP sources at

a major facility should not necessarily be subject to NESHAP. The commenter believed

many permitting authorities were improperly interpreting NESHAP applicability such that

if a source is major for one NESHAP, it is subject to all NESHAP covered emission units

at the source, even if the emission units were minor sources and would not otherwise be

subject. (IV-D-22)
4 - Other Comments

81

Response:

The commenters are incorrect in their assertion that affected sources must be

major by themselves in order to be classified as a major source. Standards apply to

major sources (and sometimes area sources when so stated) regardless of the size or

potential to emit of the affected source located at the major source. Thus, to qualify as a

major source, an affected source may be major by itself or may be located at or part of a

contiguous facility that emits or has the potential to emit 10 tons per year or more of any

individual HAP or 25 tons per year or more of any combination of HAP. This

interpretation is affirmed in National Mining Association, et al. v. EPA. (95-1006, U.S.

District Court of Appeals for the D.C. Circuit.)

4.2.7 Use of Term “Source” in Preamble

Comment:

One commenter found the use of the term “source” in the preamble confusing. The

commenter indicated two sentences in the preamble in which source was used in two

different ways. These included the last sentence beginning on page 16334 (“...the source

installs a major-emitting source after the section 112(j) deadline for sources in the same

category or subcategory.”) and the first sentence of Part F. on page 16337 (...sources

which have not been clearly identified as sources within the particular source category.) 

The commenter requested that EPA clarify its use of source in the preamble. (IV-D-01)

Response:

We agree with the commenter that these concepts are not easy to understand. We

have summarized the different source definitions in our response to comment 4.2.1.

The discussion on page 16334 to which this commenter refers deals with sources

affected by the section 112(g) requirements. These are sources that meet the definition of

major source in section 112(a)(1) of the CAA or are major-emitting units by themselves. 

The section 112(g) requirements do not apply to processes or units that fall below the

major source emission thresholds.

In the commenter’s second example, referring to page 16337, “source” in this

context refers to a source within a source category (that is, an“affected source”), and

whether or not such sources would be part of the source category affected by 112(j). 
4 - Other Comments

82

Until a 112(d) standard is promulgated, the “affected source” has not been actually

established, and the source owner or operator must rely on the source category

description or a proposed rule. In such cases, it may not be clear if a particular source is

part of a source category affected by 112(j).

4.2.8 Delisting Policy

Comment:

A few commenters disagreed with EPA’s policy that only a final, formal delisting

of a source category will terminate preconstruction MACT determinations under section

112(g). The commenters maintained that sources within categories or subcategories that

have received a grant of a delisting petition should not be subject to these requirements.

(IV-D-17, 24)

Response:

Until a source category has been formally delisted, all requirements of the

NESHAP apply. The fact that a delisting petition has been granted merely indicates that

the process has begun.
83

TECHNICAL REPORT DATA

(Please read Instructions on reverse before completing)

1. REPORT NO.

 EPA-453/R-02-002

2. 3. RECIPIENT' S ACCESSION NO.

4. TITLE AND SUBTITLE

National Emission Standards for Hazardous Air Pollutants for

Source Categories: General Provisions and Requirements for

Control Technology Determinations for Major Sources in

Accordance with Clean Air Act Sections, Sections 112(g) and

112(j) - Background Information Document for Promulgated

Standards 

5. REPORT DATE

 February 2002

6. PERFORMING ORGANIZATION CODE

7. AUTHOR(S) 8. PERFORMING ORGANIZATION REPORT NO.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

 Emission Standards Division (C504-03)

 Office of Air Quality Planning and Standards

 U.S. Environmental Protection Agency

 Research Triangle Park, NC 27711

10. PROGRAM ELEMENT NO.

11. CONTRACT/GRANT NO.

 68-D1-0118 

12. SPONSORING AGENCY NAME AND ADDRESS

 Office of Air Quality Planning and Standards

 U.S. Environmental Protection Agency

 Research Triangle Park, NC 27711

13. TYPE OF REPORT AND PERIOD COVERED

 Final

14. SPONSORING AGENCY CODE

 EPA/200/04

15. SUPPLEMENTARY NOTES

16. ABSTRACT

The General Provisions, 40 CFR 63 subpart A, and the section 112(j) rule, 40 CFR 63 subpart B, are

amended as the result of a litigation settlement agreement. The General Provisions establish general

requirements that apply to each subpart under part 63, where indicated. The section 112(j) rule establishes

the process for developing case-by-case maximum achievable control technology for major sources in

source categories for which standards are not promulgated within 18 months after the date established

under section 112(e). This document responds to comments received on the March 23, 2001 proposal of

the amendments. 

17. KEY WORDS AND DOCUMENT ANALYSIS

a. DESCRIPTORS b. IDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group

 Hazardous Air Pollutants

 General Provisions

 Section 112(j) 

Air Pollution Control

18. DISTRIBUTION STATEMENT

 Release Unlimited

19. SECURITY CLASS (Report)

 Unclassified

21. NO. OF PAGES

83

20. SECURITY CLASS (Page)

 Unclassified

22. PRICE

 EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION IS OBSOLETE