Guidance on Infrastructure State Implementation 

Plan (SIP) Elements under Clean Air Act 

Sections 110(a)(1) and 110(a)(2)

September 2013
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List of Selected Acronyms and Abbreviations

AERMOD American Meteorological Society/EPA Regulatory Model

AMTIC Ambient Monitoring Technology Information Center

AQI Air Quality Index

CAA Clean Air Act

CMAQ Community Multi-scale Air Quality [Model]

CAMx Comprehensive Air Quality Model with Extensions

CFR Code of Federal Regulations

CSAPR Cross-State Air Pollution Rule

EPA Environmental Protection Agency

EGU Electric generating unit

FIP Federal implementation plan

FR Federal Register

GHG Greenhouse gases

IBR Incorporation by reference

NAAQS National Ambient Air Quality Standards

NO2 Nitrogen dioxide

NOAA National Oceanic and Atmospheric Administration

NPS National Park Service

NSR New Source Review

OAQPS Office of Air Quality Planning and Standards

Pb Lead

PM2.5 Fine particulate matter

ppm Parts per million

PSD Prevention of significant deterioration

RAVI Reasonably Attributable Visibility Impairment

SHL Significant harm level

SIP State implementation plan (also, if indicated by the context, a tribal 

implementation plan)

SO2 Sulfur dioxide

SSM Startup, shutdown, and malfunction

TAR Tribal Authority Rule

TIP Tribal Implementation Plan

UBR Unavoidable breakdown rule

μg/m3 Micrograms per cubic meter
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Table of Contents

I. Introduction ...........................................................................................................................1

II. General Guidance on Infrastructure SIPs ..........................................................................4

Which elements of CAA 110(a)(2) affect infrastructure SIPs? .........................................4

Developing and Submitting an Infrastructure SIP Submission .........................................5

Certifications...................................................................................................................7

Determining Completeness of an Infrastructure SIP Submission....................................10

Effect of a Federal Implementation Plan on an Infrastructure SIP ..................................12

III. Guidance on Individual Infrastructure SIP Elements ....................................................18

Element A – Section 110(a)(2)(A): Emission Limits and Other Control Measures.........18

Element B – Section 110(a)(2)(B): Ambient Air Quality Monitoring/Data System ........22

Element C – Section 110(a)(2)(C): Programs for Enforcement of Control 

Measures and for Construction or Modification of Stationary Sources................23

Elements D(i)(I) and (II) – Section 110(a)(2)(D)(i): Interstate Pollution Transport.........30

Element D(ii) – Section 110(a)(2)(D)(ii): Interstate Pollution Abatement and 

International Air Pollution..................................................................................35

Element E – Section 110(a)(2)(E): Adequate Resources and Authority, Conflict of 

Interest, and Oversight of Local Governments and Regional Agencies...............39

Element F – Section 110(a)(2)(F): Stationary Source Monitoring and Reporting............45

Element G – Section 110(a)(2)(G): Emergency Episodes...............................................47

Element H – Section 110(a)(2)(H): SIP Revisions .........................................................51

Element I – Section 110(a)(2)(I): Plan Revisions for Nonattainment Areas....................52

Element J – Section 110(a)(2)(J): Consultation with Government Officials, Public 

Notification, and PSD and Visibility Protection..................................................52

Element K – Section 110(a)(2)(K): Air Quality Modeling and Submission of 

Modeling Data ...................................................................................................55

Element L – Section 110(a)(2)(L): Permitting Fees........................................................56

Element M – Section 110(a)(2)(M): Consultation and Participation by Affected 

Local Entities.....................................................................................................56
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Guidance on Infrastructure State Implementation Plan (SIP) Elements under 

Clean Air Act Sections 110(a)(1) and 110(a)(2) 

I. Introduction

Under Clean Air Act (CAA) sections 110(a)(1) and 110(a)(2), each state1 is required to 

submit a state implementation plan (SIP)

2 that provides for the implementation, maintenance, 

and enforcement of each primary or secondary national ambient air quality standard (NAAQS). 

Moreover, section 110(a)(1) and section 110(a)(2) require each state to make this new SIP 

submission within 3 years after promulgation of a new or revised NAAQS.3 This type of SIP 

submission is commonly referred to as an “infrastructure SIP.”

Section 110(a)(1) generally directs each state to submit an infrastructure SIP to the U.S. 

Environmental Protection Agency after reasonable notice and public hearing.4 Section 110(a)(2) 

specifies the substantive elements these submissions need to address, as applicable, for the 

EPA’s approval. The subsections of section 110(a)(2) list a variety of requirements, some of 

which address authority, some of which address substantive requirements, and some of which 

consist of a combination of authority and substantive requirements. The conceptual purpose of an 

 

1 These CAA sections and this guidance may also apply, as appropriate under the Tribal Authority Rule (TAR) in 40 

CFR part 49, to an Indian tribe that receives a determination of eligibility for treatment as a state for purposes of 

administering a tribal air quality management program under section 110(a) of the CAA. Tribes should look to the 

TAR and engage their respective EPA Regional Offices in discussing how this guidance may impact the 

development and approvability of their tribal implementation plans (TIPs). We encourage states to provide outreach 

and engage in discussions with tribes about their SIPs as they are being developed.

2 In the CAA and in this guidance, “plan,” “SIP,” and “TIP” may, depending on context, refer either to (i) all or part 

of the existing state (or tribal) implementation plan (i.e., the collection of all submissions previously approved by the 

EPA as meeting CAA requirements) or (ii) a submission that adds to or modifies the existing plan as directed by 

section 110(a)(l).

3 The Administrator may specify a shorter period.

4 The EPA rules provide that a public hearing must be offered by the air agency but is only required if a request is 

made.
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infrastructure SIP submission is to assure that the air agency’s5 SIP contains the necessary 

structural requirements for the new or revised NAAQS, whether by establishing that the SIP 

already contains the necessary provisions, by making a substantive SIP revision to update the 

SIP, or both. Overall, the infrastructure SIP submission process provides an opportunity for the 

responsible air agency, the public, and the EPA to review the basic structural requirements of the 

air agency’s air quality management program in light of each new or revised NAAQS.

This non-binding guidance6 provides recommendations for air agencies’ development 

and the EPA's review of infrastructure SIPs for the 2008 ozone primary and secondary NAAQS,7

the 2010 primary nitrogen dioxide (NO2) NAAQS,8 the 2010 primary sulfur dioxide (SO2) 

NAAQS,9 and the 2012 primary fine particulate matter (PM2.5) NAAQS,

10 as well as 

 

5 This guidance uses the term “air agency” to generally refer to a state, territory, or tribe that develops and submits 

an infrastructure SIP or TIP, except when quoting or paraphrasing a CAA section or a EPA regulation that uses the 

term “state.” 

6 None of the recommendations contained in this guidance are binding or enforceable against any person, and no 

part of the guidance or the guidance as a whole constitutes final agency action that could injure any person or 

represent the consummation of agency decision making. Only final actions taken to approve or disapprove SIP 

submissions that implement any of the recommendations in this guidance would be final actions for purposes of 

CAA section 307(b). Therefore, this guidance is not judicially reviewable. This document is not a rule or regulation, 

and the guidance it contains may not apply to a particular situation based upon the individual facts and 

circumstances. This guidance does not change or substitute for any law, regulation, or other legally binding 

requirement and is not legally enforceable. The use of non-mandatory language such as “guidance,” “recommend,” 

“may,” “should,” and “can” is intended to describe the EPA’s policies and recommendations. Mandatory 

terminology such as “must” and “required” is intended to describe controlling legal requirements under the terms of 

the CAA and the EPA regulations. Neither such language nor anything else in this document is intended to or 

does establish legally binding requirements in and of itself.

7 The EPA revised the levels of the primary and secondary 8-hour ozone standards to 0.075 parts per million (ppm). 

40 CFR 50.15. 73 FR 16436 (March 27, 2008).

8 The EPA revised the primary NO2 standard by adding a 1-hour level of 100 parts per billion (ppb), while retaining 

the previous annual primary and secondary standards. 40 CFR 50.11(b) and (f). 75 FR 6474 (February 9, 2010). The 

EPA has also recently reviewed the air quality criteria and the secondary NAAQS for nitrogen oxides and sulfur

oxides and retained the current NO2 and SO2 secondary standards, 77 FR 20218 (April 3, 2012).

9 On June 2, 2010, the EPA established a new 1-hour SO2 standard at a level of 75 ppb. 40 CFR 50.17. This rule also 

provided for the automatic future revocation of the previous annual and 24-hour SO2 NAAQS for most areas 

following 1 year after designation under the new NAAQS. 40 CFR 50.4(e). The previous 3-hour secondary standard 

remains in place indefinitely. 40 CFR 50.5. 75 FR 35520 (June 22, 2010). The EPA has also recently reviewed the 

air quality criteria and the secondary NAAQS for nitrogen oxides and sulfur oxides and retained the current NO2 and 

SO2 secondary standards, 77 FR 20218 (April 3, 2012).

10 The EPA revised the annual PM2.5 standard by lowering the level to 12.0 micrograms per cubic meter (μg/m3

). 78 

FR 3086 (January 15, 2013).
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infrastructure SIPs for new or revised NAAQS promulgated in the future. As a result, air 

agencies may continue to rely on this guidance for developing infrastructure SIPs for future new 

or revised NAAQS until this guidance is supplemented or replaced by future guidance. This 

guidance does not address section 110(a)(2)(D)(i)(I), which concerns interstate pollution 

transport affecting attainment and maintenance of the NAAQS. The EPA expects to issue 

guidance in the future with respect to this section of the CAA. 

Section II of this document provides general guidance for the development of 

infrastructure SIPs, and section III presents guidance on the individual elements (and subelements) that constitute an infrastructure SIP. 
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II. General Guidance on Infrastructure SIPs

Which elements of CAA 110(a)(2) affect infrastructure SIPs? 

Infrastructure SIP elements are addressed in portions of section 110(a)(2) of the CAA. 

Under this section, states are required to develop and maintain an air quality management 

program that meets various basic structural requirements, including, but not limited to:

enforceable emission limitations; an ambient monitoring program; an enforcement program; air 

quality modeling capabilities; and adequate personnel, resources, and legal authority.

Although, as stated in section I of this document, infrastructure SIPs are required to be 

submitted within 3 years after the promulgation of a new or revised NAAQS, the EPA interprets 

section 110(a)(2) to exclude two elements that could not be governed by the 3-year submission 

deadline of section 110(a)(1). Both these elements pertain to part D, in title I of the CAA, which 

addresses SIP requirements and submission deadlines for designated nonattainment areas for a 

NAAQS. Therefore, the following elements are considered by the EPA to be outside the scope of 

infrastructure SIP actions: (1) section 110(a)(2)(C) to the extent that it refers to permit programs 

(known as “nonattainment new source review”) under part D; and (2) section 110(a)(2)(I) in its 

entirety, which addresses SIP revisions for nonattainment areas. Both these elements pertain to 

SIP revisions that collectively are referred to as a nonattainment SIP or an attainment plan, which 

would be due by the dates statutorily prescribed under subparts 2 through 5 under part D, 

extending as far as 10 years following area designations for some elements. Because the CAA 

directs states to submit these plan elements on a separate schedule, the EPA does not believe it is 

necessary for states to include these elements in the infrastructure SIP submission due 3 years 

after adoption or revision of a NAAQS. While an infrastructure SIP submission is not expected 

to meet the requirements for a nonattainment SIP, the scope of an infrastructure SIP does not 

exclude geographical areas that have been designated nonattainment for the new or revised 

NAAQS or an earlier NAAQS for the same pollutant. Sections 110(a)(1) and 110(a)(2) reflect 

the congressional intent that each air agency have an air quality program, covering all 
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geographical areas of the state, that includes the specified air agency authorities, requirements, 

and activities. 

The infrastructure SIP submission requirement does not move up the date for any

required submission of a part D plan for areas designated nonattainment for the new NAAQS. 

However, in order to cover all parts of the state or area of Indian country, an infrastructure SIP 

submission may reference pre-existing SIP emission limits or other rules contained in part D 

plans for the predecessor to the relevant new or revised NAAQS. It may also include recently 

adopted emission limits that are intended to be part of the not-yet-submitted part D plan for the 

new or revised NAAQS. To avoid confusion about the legal effect of the EPA’s action on an 

infrastructure SIP submission, we intend to make clear in each final action that EPA approval of

the infrastructure SIP submission is solely with regard to whether the submission meets 

particular infrastructure SIP required elements (as opposed to nonattainment SIP elements). This 

means that the EPA may approve a submission as meeting the air agency’s obligation under 

section 110(a)(1) and 110(a)(2) stemming from the particular new or revised NAAQS, without 

necessarily determining whether the submission meets the applicable requirements for 

nonattainment SIPs under part D of title I of the CAA for the same or any other NAAQS. An 

approval on this basis will make the referenced or newly submitted SIP emission limits or other 

rules federally enforceable, and will make clear that there has been no disapproval of an 

applicable required SIP submission and thus that there is no federal implementation plan (FIP)

obligation stemming from CAA section 110(a)(1) or (2).11

Developing and Submitting an Infrastructure SIP Submission

Upon the promulgation of a new or revised NAAQS, the infrastructure SIP process 

should begin with the air agency’s review of the adequacy of its existing SIP provisions for 

 

11In general, a finding by the EPA that an air agency has failed to submit a complete SIP or an action by the EPA to 

disapprove a SIP or SIP element initiates a FIP obligation, if the submission is required by the CAA. Mandatory 

sanctions would not apply under CAA section 179 because the failure to submit a SIP is neither with respect to a 

submission that is required under CAA title I part D nor in response to a SIP call under CAA section 110(k)(5). 

Some of the sections of this guidance document address FIP implications on individual elements more specifically.
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purpose of meeting the infrastructure SIP requirements for the new or revised NAAQS. In order 

to develop an infrastructure SIP submission, an air agency may cite existing EPA-approved 

provisions and/or adopt new or revised statutory authorities and regulations, as necessary, in 

order to address each element of the infrastructure SIP. Further, with respect to a given NAAQS, 

an air agency may elect to make multiple submissions; each addressing some but not all elements 

or sub-elements of section 110(a)(2) so long as those submissions meet all of the infrastructure 

requirements in the aggregate. An air agency may also elect to make one submission to address 

infrastructure SIP requirements for multiple NAAQS, if it represents the submission as such 

during its adoption process and in its transmittal to the EPA. Of course, such a submission to 

address multiple NAAQS should establish how the air agency believes that the SIP meets each of 

the requirements of section 110(a)(2), as applicable, for each of the relevant NAAQS.

It is important that the SIP submission demonstrate the authority of the responsible air 

agency (or agencies, if responsibility for implementation is shared, e.g., between state and local 

agencies) to implement the new or revised NAAQS that has triggered the need for the 

infrastructure SIP submission. This can be an issue for approval if an older underlying legal 

authority enumerates specific ambient standards by pollutant, indicator, averaging period, level, 

and/or date of promulgation but does not include the new or revised NAAQS in its list. Air 

agencies are encouraged to discuss any situations of this type with their respective EPA Regional 

Offices. 

We encourage each air agency to consult with the appropriate EPA Regional Office, to 

consider the completeness of the submission, and to consider how the submission satisfies the 

applicable EPA regulations governing approval of infrastructure SIP submissions in 40 CFR 

part 51 ("Requirements for Preparation, Adoption, and Submittal of Implementation Plans"). The

regulations are referenced in this document, some with overlapping provisions across subparts, 

and include the following:

• Subpart A – Air Emissions Reporting Requirements

• Subpart F – Procedural Requirements

• Subpart G – Control Strategy

• Subpart H – Prevention of Air Pollution Emergency Episodes
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• Subpart I – Review of New Sources and Modifications

• Subpart J – Ambient Air Quality Surveillance

• Subpart K – Source Surveillance

• Subpart L – Legal Authority

• Subpart M – Intergovernmental Consultation

• Subpart O – Miscellaneous Plan Content Requirements

• Subpart P – Protection of Visibility

• Subpart Q – Reports

Once the air agency has made one or more infrastructure SIP submissions, the EPA will 

evaluate the submission(s) for completeness. The EPA's criteria for determining completeness of 

a SIP submission are codified at 40 CFR part 51 appendix V and are discussed in a later 

subsection of this guidance. An air agency’s familiarity with the EPA's regulatory completeness 

criteria will benefit the air agency during the process of developing an approvable submission.

The EPA’s review can be expedited if a SIP submission includes a detailed explanation 

of how the existing EPA-approved SIP in combination with any newly submitted provisions 

meets each of the applicable requirements of section 110(a)(2). The EPA expects the 

submissions to include a description of the correlation between each infrastructure element and 

an equivalent set of statutory, regulatory, and/or non-regulatory provisions, as appropriate, that 

are part of or (for some elements) are referred to by the existing SIP or the new submission. 

(Refer to section III for more detail on submission requirements for each individual element.)

When an air agency’s infrastructure SIP submission more clearly identifies the CAA element(s) 

being met by the SIP and how they are met, the EPA can more easily determine whether the 

submission is complete and approvable with respect to that element.

Certifications

Where an air agency determines that the provisions in or referred to by its existing EPAapproved SIP are adequate with respect to a given infrastructure SIP element (or subelement) 

even in light of the promulgation of a new or revised NAAQS, the air agency may make a SIP 

submission in the form of a certification. This type of infrastructure SIP submission may, e.g., 
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take the form of a letter to the EPA from the Governor or her/his designee containing a 

"certification" (or declaration) that the already-approved SIP contains or references provisions 

that satisfy all or some of the requirements of section 110(a)(2), as applicable, for purposes of 

implementing the new or revised NAAQS. In such a case, the submission would not need to 

include a paper copy of the relevant pre-existing provisions (e.g., rules or statutes).12 Rather, the 

certification submission should provide citations to the state, local, or tribal statutes, regulations, 

or non-regulatory measures, as appropriate, in or referenced by the already EPA-approved SIP 

that meet particular infrastructure SIP element requirements and should include an explanation as 

to how those existing provisions meet the relevant requirements. The air agency should consult 

with its EPA Regional Office on the wording of this type of infrastructure SIP submission prior 

to making its submission. As for any other SIP submission, an air agency (unless the EPA has 

approved a request for parallel processing) would need to provide reasonable notice and 

 

12 In contrast, where an air agency’s infrastructure SIP submission seeks the EPA’s approval of or references a new

provision (e.g., a rule or statute) that has not already been approved, or submitted for approval, into the SIP, a 

complete SIP submission should include at least one hard copy and an exact duplicate electronic version of the 

adopted provisions (unless otherwise agreed to by the air agency and the Regional Office). Memorandum dated 

April 6, 2011, from Janet McCabe, titled “Regional Consistency for the Administrative Requirements of State 

Implementation Plans and the Use of Letter Notices.” The EPA is investigating means to provide for states a method 

to transmit SIP submissions electronically with no requirement for paper copy submissions.
9

opportunity for comment prior to submitting a certification SIP submission to the EPA.13 This 

"reasonable notice and public hearing" requirement for approvable infrastructure SIP 

submissions appears at sections 110(a)(1) and the introductory text of section 110(a)(2), and it 

has much the same wording as the more generally applicable procedural requirement at 

section 110(l) of the CAA ("Plan Revisions"). See CAA sections 110(a)(1) and (2) and 110(l). 

Compliance with this procedural requirement is verified through an additional certification by 

the air agency that a public hearing (if one was requested) was held in accordance with the EPA's 

regulatory procedural requirements for public hearings.14 See 40 CFR 51.102 and 40 CFR 

part 51, appendix V, paragraph 2.1(g).

 

13 The EPA regulations at 40 CFR part 51 appendix V provide that a public hearing must always be offered and that 

a hearing must be held if requested. The EPA has received comment that when all of the elements in an existing 

infrastructure SIP were previously subject to a public comment process, including the opportunity for public 

hearing(s), when they were first submitted for the EPA's approval and incorporation into the SIP, no public 

comment requirements should apply to a “certification” infrastructure submission. The EPA believes this suggested 

interpretation is inconsistent with the plain text of section 110(a)(1) of the CAA. Section 110(a)(1) first provides that 

“[e]ach State shall, after reasonable notice and public hearings, adopt and submit to the Administrator, within 

3 years (or such shorter period as the Administrator may prescribe) after the promulgation of a [primary NAAQS] 

(or any revision thereof) ... a plan [i.e., infrastructure SIP] which provides for implementation, maintenance, and 

enforcement of such primary standard.” The clause “after reasonable notice and public hearings” is most naturally 

read as imposing that procedure on the immediately following phrase, “adopt and submit,” the direct object of which 

is the infrastructure SIP itself. The suggested interpretation would instead apply the phrase “after reasonable notice 

and public hearings” to SIP revisions submitted before the promulgation of the new or revised primary NAAQS, 

despite the complete absence of a reference to those earlier SIP revisions in section 110(a)(1). Any possible residual 

ambiguity is removed by the last sentence of section 110(a)(1), which requires an infrastructure SIP for a secondary 

NAAQS to be considered (unless a separate public hearing is provided) “at the hearing required by the first sentence 

of this paragraph.” The only possible interpretation of this sentence is that there must be an opportunity for public 

hearing for the infrastructure SIPs for both the primary and secondary NAAQS. This is a reasonable interpretation 

because it informs the public that the SIP is being revised and allows for comment as to whether the air agency’s 

earlier approved regulations also satisfy the relevant obligation stemming from the promulgation of the new or 

revised NAAQS. Furthermore, the next footnote explains that the EPA has recently clarified procedures for 

providing notice and opportunity for comment that reduce the burden on air agencies while still assuring adequate 

notice to the public.

14 Additional guidance regarding how an air agency may submit a SIP or a SIP revision can be found in a 

memorandum dated April 6, 2011, from Janet McCabe, Deputy Assistant Administrator, Office of Air and

Radiation, to Regional Administrators, titled "Regional Consistency for the Administrative Requirements of State 

Implementation Plans and the Use of 'Letter Notices'." Refer also to a memorandum dated Nov. 22, 2011, jointly 

from Janet McCabe, Deputy Assistant Administrator, Office of Air and Radiation, and Becky Weber, Director, Air 

and Waste Management Division, Region 7, to Air Division Directors, Regions 1-10, titled "Guidelines for 

Preparing Letters Submitting State Implementation Plans (SIPs) to EPA and for Preparing Public Notices for SIPs." 

These guidance memos identify certain streamlining approaches that are available to an air agency, depending on the 

situation.
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As with any SIP submission, the EPA’s review can be expedited if a SIP certification 

submission includes a detailed explanation of how the existing SIP meets each of the applicable

requirements of section 110(a)(2). This should include a description of the correlation between 

each infrastructure element and an equivalent set of statutory, regulatory, and/or non-regulatory 

provisions, as appropriate, that are part of or are referenced by the existing SIP. When an air 

agency’s infrastructure certification submission more clearly identifies the CAA element(s) 

being met by the SIP and how they are met, the EPA can more easily determine whether the 

submission is complete and approvable with respect to that element.

Determining Completeness of an Infrastructure SIP Submission

Section 110(k)(2) directs the EPA to take final action on a SIP submission within 1 year

after the submission is determined to be complete under section 110(k)(l). If the EPA makes an 

affirmative finding that a SIP submission is complete, the date of the finding establishes the 

"completeness date" for the submission. If, however, the EPA makes no affirmative 

completeness finding, then the submission is deemed complete by operation of law on the date 

6 months after the submission date. A finding that an infrastructure SIP submission is complete

does not necessarily mean that the submission is approvable; the completeness review only 

addresses whether the air agency has provided information sufficient to commence formal EPA 

review for approvability. Refer to 40 CFR part 51 appendix V ("Criteria for Determining the 

Completeness of Plan Submissions").

Historically, when reviewing infrastructure SIP submissions, the EPA has operated on the 

basis that the elements and sub-elements of section 110(a)(2) for a given NAAQS are, for the 

most part, severable.15 The EPA may elect to make a finding of failure to submit in whole or in 

part, based upon whether a state has made a complete infrastructure SIP submission for the 

relevant elements of section 110(a)(2). For a state that has not made any infrastructure SIP 

 

15 See, e.g., 76 FR 81371 (December 28, 2011), “Approval and Promulgation of Implementation Plans; Texas;

Infrastructure and Interstate Transport Requirements for the 1997 Ozone and the 1997 and 2006 PM2.5 NAAQS, 

Final Rule,” where the EPA approved severable portions of infrastructure SIP revisions submitted by Texas.
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submission, the EPA generally will make a finding with respect to all of the relevant elements.16

For a state that has made a SIP submission but whose submission is incomplete for some of the 

relevant elements, the EPA generally will issue a finding of failure to submit only with respect to 

those elements. This separation makes clear what mandatory EPA duty subsequently exists with 

respect to each element or subelement. If the EPA has made separate findings as to the 

completeness of submissions for two or more elements (and sub-elements), the 12-month 

statutory deadline for EPA action to approve or disapprove the elements for which the air agency 

has made a complete submission and the 24-month statutory deadline for EPA action to 

promulgate FIPs for incomplete elements would apply separately. The EPA intends to continue 

its practice of acting on infrastructure SIP elements together or separately, as appropriate. 

Any SIP submission is deemed by operation of law to be complete six months after 

submission, unless the EPA has before that date made an affirmative finding that the submission 

is complete or incomplete. Any inconsistency between the scope of the submission as described 

in the pre-submission public notice of the SIP submission and the actual submission, or between 

the description of the scope of the submission in the transmittal letter to the EPA and the actual 

substantive coverage of the submission can create ambiguity as to which infrastructure SIP 

elements in fact have been submitted and thus are capable of becoming complete by operation of 

law (and triggering a deadline for the EPA’s action) and which have in fact not yet been 

submitted.17 To provide clarity for all parties, air agencies should be very clear and accurate in 

the wording of their public notices and transmittal letters. It is also advisable for the air agency to 

discuss this wording with its EPA Regional Office before submission. On its part, an EPA 

Regional Office, in receipt of a submission with any inconsistencies of the type described, should 

consider steps it can take or ask the air agency to take prior to the six-month point in order to 

avoid the creation of ambiguity or an incorrect result as to which SIP elements have actually 

 

16 Under the TAR, a tribe is not subject to deadlines for certain planning requirements (including submission of 

infrastructure SIPs). See 63 FR 7254 (Feb. 12, 1998) for more information.

17 The EPA’s experience is that the existence of a FIP for PSD or regional haze may increase the risk of such 

inconsistencies occurring inadvertently. FIP-related aspects are discussed in more detail in the next section of this 

guidance.
12

been submitted and are complete and consequently subject to a statutory deadline for the EPA 

action.

Section 2.3 of 40 CFR part 51 appendix V waives certain completeness requirements if

the EPA has granted an air agency request for parallel processing of the submission. Under the 

parallel processing approach, the EPA proposes to approve a draft SIP submission so that final 

approval can be given more quickly after the final adoption of any new measures as state, local, 

or tribal law and conclusion of the public comment process normally required for any SIP 

submission. The EPA intends to grant requests for parallel processing of infrastructure SIP 

submissions if (1) the only missing elements of completeness are final state adoption of rules or 

other provisions and/or conclusion of the public comment process for the SIP submission, 

including evidence thereof as specified in section 2.3 of appendix V, and (2) the schedule 

provided by the air agency for the conclusion of the adoption process and/or the public comment 

process for the SIP submission is reasonably expeditious.

18 In such a case, the EPA generally 

would also either make a finding of completeness for the submission or allow it to become 

complete by operation of law. If both these conditions are not met, the EPA will not grant the 

parallel processing request. However, the EPA generally will not make a finding of failure to 

submit a complete SIP but may be required to do so if under a court order.

Effect of a Federal Implementation Plan on an Infrastructure SIP

The CAA directs states to submit SIPs to the EPA for approval. In some cases, and for 

various reasons, the EPA may have previously determined that an air agency had not satisfied a 

SIP requirement, and so accordingly promulgated a FIP to address the gap in the SIP. The 

infrastructure SIP process can be affected when an air agency is currently subject to a FIP that is 

related to an infrastructure SIP element. Therefore, this section describes the potential impact of 

pre-existing FIPs on the infrastructure SIP process. This explanation is relevant not only for air 

 

18 With regard to the 1992 EPA Memorandum from John Calcagni, Air Quality Management Division, OAQPS, to 

EPA Air Division Directors, Regions I through X, “State Implementation Plan (SIP) Actions Submitted in Response 

to Clean Air Act (Act) Deadlines,” October 29, 1992, note that the EPA no longer considers the section titled 

“Requests for Parallel Process to Meet Act Deadlines” to be its guidance for infrastructure SIPs that are submitted 

with requests for parallel processing.
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agencies that currently have a FIP in effect but also for air agencies that may be subject to a FIP 

in the future. 

The EPA’s obligation to promulgate a FIP is set out in section 110(c) of the CAA. A FIP 

may be triggered if the EPA takes any of the following actions: (1) the EPA finds that a state has 

failed to make a required SIP submission; (2) the EPA finds that a required submission was 

incomplete; or (3) the EPA disapproves a required SIP submission in whole or in part. If the EPA

takes one of these actions, section 110(c) obligates the EPA to promulgate a FIP within 2 years

of the action, a deadline that is commonly referred to as a "FIP clock." In order to remove the 

EPA's FIP obligation, the state must make a SIP submission that meets the applicable CAA 

requirements and is approved by the EPA prior to the EPA’s promulgation of a FIP. Whenever 

the EPA promulgates a FIP for a state air agency, the FIP rulemaking will identify the specific 

CAA provisions that required the promulgation of the FIP, and the FIP will be codified in the 

appropriate section of 40 CFR part 52.

Under the TAR, a tribe is not subject to deadlines for planning requirements (including 

submission of infrastructure SIPs).

19 In general, the concept of failure to submit a complete 

implementation plan does not apply in tribal situations, and there is no FIP clock started if a tribe 

has not submitted an infrastructure TIP. Under the TAR, in the absence of an approved tribal 

implementation plan the EPA will promulgate a FIP for one or more infrastructure SIP elements 

when and if it is necessary and appropriate to do so. For example, the EPA has promulgated new 

source review FIPs to govern permitting of sources in Indian country.

If the EPA has promulgated a FIP, then this means that the EPA has previously 

determined that the air agency’s SIP did not meet some CAA requirement as of the date of 

promulgation of that FIP. While the intent and effect of the FIP is to achieve the same air quality 

protection as the SIP should have achieved, it is the EPA’s interpretation of sections 110(a)(1) 

and 110(a)(2) that the EPA cannot give “credit” for the FIP when determining whether an air 

agency has met any later obligations under these sections.

 

19 See 63 FR 7254 (February 12, 1998) for more information on the TAR.
14

As an example of a FIP that affects the infrastructure SIP submission process, we note 

that, for various reasons, several states do not have EPA-approved major source preconstruction 

permit programs in their SIPs for prevention of significant deterioration (PSD) as required by 

part C of title I of the CAA. The EPA has promulgated a set of PSD rules which establish 

authority for the EPA (or an air agency to which the EPA has delegated authority to administer 

the federal PSD program)20 to issue preconstruction permits to major stationary sources in any 

area not covered by a PSD program in a SIP.21 The EPA has also promulgated FIPs for each area 

without a SIP-approved PSD program, indicating that this set of federal PSD rules applies in that 

area.

22 Such a PSD FIP may be relevant to infrastructure Element C, Element J, Element D(i)(II), 

and the portion of Element D(ii) related to notification to other states. As another example, the 

EPA has promulgated full or partial FIPs to address reasonably attributable visibility impairment 

(RAVI) and regional haze for some air agencies.23 A RAVI FIP or a regional haze FIP may be 

relevant to Element D(i)(II). These linkages are further discussed in the section pertaining to 

each of these elements.

The infrastructure SIP process will vary to some extent depending on whether or not the 

air agency’s SIP submission purports to, and actually does, satisfy infrastructure SIP 

requirements that are currently being met by means of a FIP, as explained in the following 

paragraphs. 

Consider an air agency that is currently subject to a FIP that is relevant to certain 

infrastructure SIP elements makes a submission and states in a general way in the transmittal 

letter that the submission satisfies all elements of CAA section 110(a)(2), or if it specifically 

states that the submission satisfies the elements to which the FIP is relevant, the EPA would 

 

20 The EPA is planning on extending the opportunity for delegation of new source review permitting to qualified 

tribes.

21 See 40 CFR 52.21; Prevention of Significant Deterioration of Air Quality.

22 See, e.g., 40 CFR 52.738 for the PSD program applicable to sources in Illinois.

23 Some of these regional haze FIPs relied on the Cross-State Air Pollution Rule (CSAPR), which was subsequently 

vacated by the U.S. Court Appeals for the D.C. Circuit. EME Homer City Generation, L.L.P. v. EPA, 696 F.3d 7 

(D.C. Cir. 2012). The Supreme Court has accepted the EPA’s petition for it to review the D.C. Circuit’s decision. 

Air agencies should consult with their EPA Regional Offices regarding the current status of this litigation and the 

implications if any for infrastructure SIP submissions.
15

evaluate whether the submission, in fact, contains existing or new substantive provisions to 

address the section 110(a)(2) requirement presently covered by the FIP. If the submission does 

not substantively address the elements or sub-elements presently covered by the FIP, then the 

EPA Regional Office should encourage the air agency to clarify its intentions as to which 

elements have been submitted. The air agency might then clarify that it has made no submission 

for certain elements, in which case the EPA would not make a finding of complete submission 

for those elements and those elements could not become complete by operation of law. (The 

EPA may make a finding of failure to submit for those elements.) In the absence of such a 

clarification, the EPA Regional Office should determine that the air agency has failed to make a 

complete submission for those elements. Such a finding generally would create an obligation for 

the EPA to adopt a FIP within 24 months. However, based on the PSD FIP example and to the 

extent that the SIP deficiency is addressed by continuing to implement the existing PSD FIP, the 

EPA would have no additional FIP obligation under section 110(c) and the air agency would not 

have to take any further action for the current FIP-based permitting process to continue 

operating. Mandatory sanctions would not apply under CAA section 179 because such a finding 

of failure to submit a complete SIP was made neither with respect to a submission that is 

required under CAA title I part D nor in response to a SIP call under CAA section 110(k)(5).

To provide further clarity, consider how the following three scenarios may prompt 

differing EPA actions. 

First scenario. Under this scenario, the transmittal letter for the infrastructure SIP 

submission makes clear that the submission is not intended to satisfy certain elements that can be

addressed by continuing to apply the FIP. In this situation, the EPA would make a completeness 

finding that extends only to the SIP elements actually submitted by the air agency, and a finding 

that other relevant applicable elements were not submitted.24 The EPA would be required to take 

action only on the elements that were submitted, within 12 months after those elements have 

been determined to be complete. The overall infrastructure SIP would not be approvable with 

 

24 If, instead, the submission that clearly addressed only some required elements has become complete at the 6-

month point by operation of law, the EPA would still consider the air agency to not have made a complete

submission for the missing elements.
16

respect to the elements that were not submitted, and thus the EPA could only partially approve 

the overall infrastructure SIP.

25

Second scenario. Under the second scenario, suppose the air agency makes a SIP 

submission that references the existence of a PSD FIP and asserts that the existence of the FIP is 

a sufficient basis for EPA approval of the submission with respect to these elements. The EPA 

would not consider the existence of the PSD FIP, even if referenced in the submission, as 

meeting completeness or approvability criteria for these elements. This is because a FIP is not a 

state plan and thus cannot serve to satisfy the state’s obligation to submit a SIP. The EPA’s 

action on the SIP submission would indicate that the air agency has not met the underlying 

statutory obligations in section 110(a)(2) with respect to Elements C and J. However, when the 

SIP deficiency is being addressed by the existing PSD FIP, the EPA would have no additional 

FIP obligation under section 110(c) and the state would not have to take any further action for

the current FIP-based permitting process to continue operating. In this example, the EPA may be 

able to approve a state-developed SIP later, if the air agency develops and submits a SIP meeting 

all statutory and regulatory requirements relevant to Elements C and J. 

Third scenario. Under this scenario, the transmittal letter for the infrastructure SIP 

submission explicitly or implicitly indicates that the submission is intended to satisfy all required 

elements (including the elements that may be addressed by continuing to apply the existing PSD 

FIP), and the 6-month point has passed without any clarification by the air agency or any finding 

by the EPA Regional Office regarding completeness. In this situation, the EPA will generally 

treat the submission as having been intended to address all the required elements and to be 

complete for all elements. The 12-month clock for EPA action on the submission would apply to 

all elements and the EPA would proceed to disapprove the submission for the same elements 

with respect to the subject NAAQS that were previously addressed in the context of earlier 

NAAQS by the FIP. However, similar to the first scenario in which the SIP deficiency has 

 

25 Note: Because an infrastructure SIP is not a required plan submission under part D of title I of the CAA, 

disapproval of (or a finding of failure to submit) an infrastructure SIP or element thereof does not trigger mandatory 

sanctions under CAA section 179, unless the submission was required in response to a SIP call under 

section 110(k)(5) of the CAA.
17

already been addressed, to the extent that the existing FIP addresses the deficiency, the EPA 

would have no additional FIP obligation under section 110(c) and the state would not have to 

take any further action for the current FIP-based permitting process to continue operations. As in 

the first scenario, the EPA may be able to approve a state-developed SIP later, if the air agency 

develops and submits a SIP meeting all statutory and regulatory requirements relevant to 

Elements C and J.

For some state air agencies and some sources in Indian country, there are RAVI or 

regional haze FIPs in place that may be relevant to the subelement of Element D(i)(II) related to 

interference with measures by another state to protect visibility. This subelement is sometimes 

referred to as the “visibility transport” prong or simply, as “prong 4.” While fully approved 

RAVI and regional haze SIPs can be relied upon in satisfying this subelement, as explained later 

in this document, it may be possible in some cases for the element to be satisfied even if there is 

a FIP in place. Air agencies in this situation should read the section on Element D(i)(II) and 

consult with their respective EPA Regional Offices on this aspect of their infrastructure SIP 

submission.

If a new submission in fact does address the substance of the element or subelement 

covered by a FIP, the EPA would review the submission and may approve the infrastructure SIP. 

The EPA may also withdraw the FIP that had been addressing that element or subelement for 

previous NAAQS, if all relevant CAA requirements are met by the SIP.
18

III. Guidance on Individual Infrastructure SIP Elements

The EPA interprets section 110(a)(1) and section 110(a)(2) to require infrastructure SIP 

submissions to meet the elements of section 110(a)(2), as applicable. As described in section II, 

the EPA interprets the portion of section 110(a)(2)(C) that pertains to a permitting program that 

applies to nonattainment NSR within nonattainment areas, and the requirements of 

section 110(a)(2)(I) that pertain to the specific requirements for attainment plans for designated 

nonattainment areas, to be outside the scope of the infrastructure SIP requirements because of the 

separate statutory schedules for area designations and submission of attainment plans provided 

elsewhere in the CAA. With respect to the remaining elements of section 110(a)(2), 

subsections (A) through (M), the CAA imposes an obligation on states to address those elements, 

as appropriate, within the 3-year infrastructure SIP submission deadline. This section provides 

recommendations to air agencies about how to make infrastructure SIP submissions to meet 

these remaining relevant elements, as applicable. 

Element A – Section 110(a)(2)(A): Emission Limits and Other Control Measures

Each such plan shall –

(A) include enforceable emission limitations and other control measures, means, 

or techniques (including economic incentives such as fees, marketable permits, 

and auctions of emissions rights), as well as schedules and timetables for 

compliance, as may be necessary or appropriate to meet the applicable 

requirements of this Chapter.

To satisfy Element A, an air agency’s submission should identify existing EPA-approved 

SIP provisions or new SIP provisions that the air agency has adopted and submitted for EPA 

approval that limit emissions of pollutants relevant to the subject NAAQS, including precursors 

of the relevant NAAQS pollutant where applicable. Emissions limitations and other control 

measures needed to attain the NAAQS in areas designated nonattainment for that NAAQS will 

be due on a different schedule from the section 110 infrastructure elements and will be reviewed 

and acted upon with regard to approvability for the specific purposes of such an attainment plan 

under CAA title I part D through a separate process at a later time. See “Which elements of CAA 
19

110(a)(2) affect infrastructure SIPs?” in section II of this guidance for additional discussion of 

this distinction.

There are two issues that relate to Element A for which we are providing general 

guidance. These are whether air agencies would need to correct the following in order for the 

EPA to approve their infrastructure SIP submissions: (1) previously approved emissions 

limitations that may treat startup, shutdown, and malfunction (SSM) events inconsistently with 

the CAA as interpreted by our longstanding guidance on excess emissions (the EPA’s SSM 

Policy) and more recently by multiple courts; and (2) previously approved SIP provisions for 

"director's variance" or "director's discretion" that purport to allow revisions to or exemptions 

from SIP emission limitations with limited public process or without requiring further approval 

by the EPA.26 The guidance provided here is consistent with the EPA interpretations articulated 

in provisions in several recent EPA final actions on SIPs.

27, 28

In recent infrastructure SIP actions, the EPA has drawn an important distinction with 

respect to SSM issues and director’s discretion issues in this particular context. The EPA does 

not interpret section 110(a)(2) to require air agencies and the EPA to address potentially deficient 

 

26 For further description of EPA's SSM Policy, see, e.g., a memorandum dated September 20, 1999, titled, "State 

Implementation Plans: Policy Regarding Excess Emissions During Malfunctions, Startup, and Shutdown," from 

Steven A. Herman, Assistant Administrator for Enforcement and Compliance Assurance, and Robert Perciasepe, 

Assistant Administrator for Air and Radiation. Also, the EPA issued a proposed action on February 12, 2013, titled 

“State Implementation Plans: Response to Petition for Rulemaking; Findings of Substantial Inadequacy; and SIP 

Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown and Malfunction.” 

This rulemaking responds to a petition for rulemaking filed by the Sierra Club that concerns SSM provisions in 

39 states’ SIPs. It clarifies and restates the EPA’s SSM SIP policy.

27 See, e.g., a SIP call issued to Utah (72 FR 21639, Apr. 18, 2010) concerning treatment of malfunction events 

under Utah's "unavoidable breakdown rule" (UBR). The EPA determined that Utah’s SIP was substantially 

inadequate because its UBR allowed operators of CAA-regulated facilities to avoid enforcement actions when they 

suffer an unexpected and unavoidable equipment malfunction. In this SIP call, the EPA called on Utah to 

promulgate a new UBR that conforms to the EPA’s interpretation of the CAA. Litigants maintained that the SIP call 

was arbitrary and capricious and asked the Tenth Circuit Court to vacate it. The Court denied the petition for review 

of the Utah SIP call. U.S. Magnesium, LLC v. EPA, U.S. Court of Appeals, No. 09-1269, January 14, 2011. 

28 As another example that presents the EPA's position on infrastructure SIPs with respect to this issue, see the 

preamble language in the final rule published in the Federal Register on July 13, 2011 (76 FR 41075), "Approval 

and Promulgation of Air Quality Implementation Plans; Illinois; Indiana; Michigan; Minnesota; Ohio; Wisconsin; 

Infrastructure SIP Requirements for the 1997 8-Hour Ozone and PM2.5 National Ambient Air Quality Standards." In 

section II of the preamble, the EPA described at length the position summarized in this guidance regarding existing 

provisions related to excess emissions during periods of SSM and existing provisions related to "director's variance" 

or "director's discretion."
20

pre-existing SIP provisions of these types in the context of acting on an infrastructure SIP 

submission. The EPA considers this a reasonable interpretation of the CAA in such a context. 

The EPA notes that it has alternative tools in the CAA to address existing SIP deficiencies of this 

type, in appropriate circumstances.

However, any “new” provisions in the infrastructure SIP submission that are relevant to 

SSM (e.g., any newly created enforcement discretion provisions, affirmative defense provisions, 

or special emissions limitations that apply during SSM periods but that have not already been 

approved by the EPA) should be consistent with the EPA’s policy on what types of SSM 

provisions are permissible in SIPs under the CAA. For instance, new provisions as part of an 

approvable SIP submission cannot allow an air director the discretion to determine whether an 

instance of excess emissions is a violation of an emission limitation, because such a 

determination could bar the EPA and citizens from enforcing applicable requirements. Similarly, 

new provisions in a SIP for the exercise of enforcement discretion with regard to SSM events 

may only apply to state or tribal government personnel so that they do not limit enforcement by 

the EPA or citizens. Excess emissions, including those occurring during SSM periods, might 

prevent attainment and maintenance of the NAAQS and compliance with other applicable CAA 

requirements. The EPA views all periods of excess emissions as violations of the applicable 

emission limitation. Therefore, if an infrastructure SIP contains provisions that have not already 

been approved by the EPA, and that impermissibly exempt from enforcement excess emissions 

that may occur at a facility during SSM periods or that otherwise are inconsistent with the EPA’s 

interpretation of the CAA as outlined in its SSM Policy, the EPA will not propose to fully

approve the submission as meeting section 110(a)(1) and (2) requirements.

With regard to “director’s discretion” to revise emission limits, any "new" provisions in 

the infrastructure SIP submission (i.e., provisions that have not already been approved by the 

EPA) should be consistent with the EPA's interpretation of the CAA as expressed in its policy

regarding director's discretion.

29

 

29 See 77 FR 34309 and 34311 (June 11, 2012). “Approval and Promulgation of Implementation Plans; Tennessee;

110(a)(1) and (2) Infrastructure Requirements for the 1997 Annual and 2006 24-Hour Fine Particulate National

Ambient Air Quality Standards, Proposed Rule.”
21

The EPA will continue to consider for approval, as it has in recent final SIP actions,30

SIPs that provide for a limited affirmative defense to civil penalties for excess emissions 

occurring during properly demonstrated and documented malfunction periods.

In summary, the EPA in recent final actions on infrastructure SIP submissions has 

maintained that the CAA does not require that new infrastructure SIP submissions address 

existing potentially inadequate provisions concerning SSM or director's discretion in order to be 

approved as meeting the CAA section 110(a)(1) and (2) requirements triggered by the new or 

revised NAAQS. The EPA’s stated position has been that it can approve an infrastructure SIP 

submission, even if the infrastructure SIP may incorporate by reference previously approved SIP 

provisions that are or may not be consistent with the EPA’s SSM Policy and its policy on 

director’s discretion to revise emission limits. The EPA articulated this position in a number of 

infrastructure SIP actions taken in 2011, noting in the preambles for those actions that existing 

provisions for SSM and director's discretion may be dealt with separately, outside the context of 

acting on an air agency’s new infrastructure SIP submission.31 However, if an air agency submits 

an infrastructure SIP submission that would create a new SIP provision related to SSM that is 

inconsistent with the EPA’s interpretation of the requirements of the CAA, the EPA may 

disapprove it. We intend to continue this practice and affirm it as part of this guidance.

 

30 See 75 FR 68989 at 68992 (November 10, 2010), “Approval and Promulgation of Implementation Plans; Texas: 

Excess Emissions During Startup, Shutdown, Maintenance, and Malfunction Activities.” In Luminant Generation 

Co. v. EPA, No. 10-60934, 2012 WL 4841615 (5th Cir. 2012), the Court upheld the EPA’s approval of an 

affirmative defense for malfunctions and disapproval of an affirmative defense provision in a SIP submission that 

pertained to “planned activities,” which included startup, shutdown, and maintenance. The EPA disapproved this 

provision, in part because it provided an affirmative defense for maintenance. The Court rejected challenges to the 

EPA’s disapproval of this provision, holding that under Chevron step 2, the EPA’s interpretation of the CAA was 

reasonable. See also the Federal Register notice signed on February 12, 2013, restating the EPA’s policy on 

affirmative defense provisions and proposing 36 SIP calls to correct affirmative defense and other SSM-related SIP 

provisions.

31 As one example of preamble language that presents the EPA's position on infrastructure SIPs with respect to this 

issue, see the final rule published in the Federal Register on July 13, 2011 (76 FR 41075), "Approval and 

Promulgation of Air Quality Implementation Plans; Illinois; Indiana; Michigan; Minnesota; Ohio; Wisconsin; 

Infrastructure SIP Requirements for the 1997 8-Hour Ozone and PM2.5 National Ambient Air Quality Standards." In 

section II of the preamble, the EPA described at length the position summarized here regarding existing provisions 

related to excess emissions during periods of SSM and existing provisions related to "director's variance" or 

"director's discretion." 
22

Element B – Section 110(a)(2)(B): Ambient Air Quality Monitoring/Data System

Each such plan shall –

(B) provide for establishment and operation of appropriate devices, methods, 

systems, and procedures necessary to –

 (i) monitor, compile, and analyze data on ambient air quality, and 

 (ii) upon request, make such data available to the Administrator.

To meet Element B requirements, the best practice for an air agency submitting an

infrastructure SIP would be to submit, for inclusion into the SIP (if not already part of the SIP),

the statutory or regulatory provisions that provide the air agency or official with the authority 

and responsibility to perform the actions listed in the bullets below along with a narrative 

explanation of how the provisions meet the requirements of this element.32

• Monitor air quality for the relevant NAAQS pollutant(s) at appropriate locations in 

accordance with the EPA's ambient air quality monitoring network requirements. See

the EPA's Ambient Monitoring Technology Information Center (AMTIC) website, 40 

CFR part 53 ("Ambient Air Monitoring Reference and Equivalent Methods"), and 40 

CFR part 58 ("Ambient Air Quality Surveillance"). See also 40 CFR 51.190 

(referencing 40 CFR part 58).33

• Submit data to the EPA's Air Quality System (AQS) in a timely manner in 

accordance with 40 CFR part 58. Under 40 CFR part 58, subpart B ("Monitoring 

Network"), for example, see 40 CFR 58.16 ("Data submittal and archiving 

requirements").

• Provide to the EPA Regional Office information regarding air quality monitoring 

activities, including a description of how the air agency has complied with monitoring 

requirements, and an explanation of any proposed changes to the network. 

 

32 The EPA recognizes that some air agencies may have general authorizing provisions that do not specifically 

enumerate specific activities but do implicitly authorize the air agency to perform such activities, in which case 

inclusion of those provisions would meet the intent of this best practice.

33 Note that despite the recent reorganization of 40 CFR part 58 without a corresponding conforming update of the 

cross-reference to part 58 in 40 CFR 51.190, all requirements under part 58 must still be met.
23

Submission of annual monitoring network plans consistent with the EPA's ambient air 

monitoring regulations is one way of providing this information. Under 40 CFR 

part 58, subpart B, see, e.g., 40 CFR 58.10 ("Annual monitoring network plan and 

periodic network assessment").

• Obtain the EPA’s approval of any planned changes to monitoring sites or to the 

network plan, consistent with applicable requirements in 40 CFR 58.14 (“System 

Modification”).

If an air agency chooses not to include the relevant statute or regulation in its SIP, then 

the air agency should provide a reference or citation to the authority provisions along with a 

narrative explanation of how the provisions meet the requirements of this element, as well as a 

copy of the relevant authority to accompany the SIP as required by 40 CFR 51.231.

For any new or revised NAAQS, the infrastructure SIP submission should provide

assurance that the state will meet changes in monitoring requirements related to the new or 

revised NAAQS.

Element C – Section 110(a)(2)(C): Programs for Enforcement of Control Measures and for 

Construction or Modification of Stationary Sources.

Each such plan shall –

(C) include a program to provide for the enforcement of the measures described 

in subparagraph (A), and regulation of the modification and construction of any 

stationary source within the areas covered by the plan as necessary to assure that 

national ambient air quality standards are achieved, including a permit program 

as required in parts C and D of this Subchapter.

This element consists of three sub-elements; enforcement, state-wide regulation of new 

and modified minor sources and minor modifications of major sources; and preconstruction 

permitting of major sources and major modifications in areas designated attainment or 

unclassifiable for the subject NAAQS as required by CAA title I part C (i.e., the major source 
24

PSD program).34,35 While this section outlines the general requirements for approvability of an 

infrastructure SIP with respect to Element C, air agencies previously subject to FIPs with respect 

to this element for major source PSD in the context of earlier NAAQS have the option, as 

discussed in more detail below and in Section II: “Which elements of CAA 110(a)(2) affect 

infrastructure SIPs?”, to remain subject to those FIPs as the remedy for infrastructure SIP 

deficiencies for a new or revised NAAQS.

Enforcement: To satisfy this subelement, an infrastructure SIP submission should identify 

the statutes, regulations, or other provisions in the existing SIP (or new provisions that are 

submitted as part of the infrastructure SIP to be incorporated into the SIP) that provide for 

enforcement of those emission limits and control measures that the air agency has identified in 

its submission for purposes of satisfying Element A (Emissions limits and other control 

measures). 

Regulation of minor sources and minor modifications: To satisfy the subelement for preconstruction regulation of the modification and construction of minor stationary sources and the 

minor modification of major stationary sources, an infrastructure SIP submission should identify

the existing EPA-approved SIP provisions and/or include new provisions that govern the minor 

source pre-construction program that regulates emissions of the relevant NAAQS pollutant(s).

The EPA rules addressing SIP requirements for pre-construction regulatory programs that apply 

to minor sources and minor modifications are at 40 CFR sections 51.160 through 51.164. 

 

34 The terms "major" and "minor" categorize a stationary source or a modification of a stationary source, for NSR 

applicability purposes, in terms of an annual emissions rate (tons per year) or change in annual emission rate for a 

pollutant. The pre-construction minor NSR program generally applies to minor stationary sources and minor 

modification projects at major stationary sources. A major “stationary source” is defined in the applicable PSD or 

nonattainment NSR regulations. Some air agencies exempt small minor sources and modifications from preconstruction regulatory requirements. 

35 As explained in section II of this document, the EPA considers evaluation of permit provisions that implement 

CAA title I part D (the major source nonattainment NSR program) to generally be outside the scope of infrastructure 

SIP actions. Hence, to address the sub-element regarding major source permitting, only the major source permitting 

program applicable in areas designated attainment or unclassifiable is an issue. In contrast, because part D does not 

impose any special requirements for permitting of minor sources in nonattainment areas, the infrastructure SIP due 

3 years after a new or revised NAAQS should address Element C with regard to minor sources in unclassifiable, 

attainment, and nonattainment areas, without regard to designation.
25

Preconstruction PSD permitting of major sources:36 To satisfy the subelement regarding 

the PSD program required by CAA title I part C, an infrastructure SIP submission should 

demonstrate that one or more air agencies has the authority to implement a comprehensive PSD 

permit program under CAA title I part C, for all PSD-subject sources located in areas that are 

designated attainment or unclassifiable for one or more NAAQS. The infrastructure SIP

submission should also identify the existing SIP provisions that govern the major source PSD 

program. As explained in more detail below, to be approvable the infrastructure SIP submission 

should also address any new or revised PSD permitting program requirements for which the 

deadline for SIP submissions has passed as of the date of EPA’s proposed action on the 

infrastructure submission. 

The SIP permitting provisions that implement CAA title I part C (the PSD program) 

govern preconstruction review and permitting of any new or modified major stationary sources 

of air pollutants regulated under the CAA (as well as any precursors to the formation of those 

pollutants when identified for regulation by the Administrator) in areas designated as attainment 

or unclassifiable. The EPA rules providing the minimum requirements for approvable PSD 

programs can be found generally at 40 CFR 51.166 (general provisions for PSD programs 

approved in SIPs) and 40 CFR 51.307 (specific provisions pertaining to new source review for 

potential impacts on air quality related values in Class I areas).

The EPA interprets Element C to mean that each infrastructure SIP submission for a 

particular NAAQS would need to demonstrate that the air agency has a complete PSD permitting

program in place covering the requirements for all regulated NSR pollutants, including 

greenhouse gases (GHG), in order to demonstrate that the SIP meets Element C.

37

Element C requires that each infrastructure SIP contain a permitting program “as required 

by part C.” CAA title I part C is applicable to all pollutants subject to regulation under the CAA. 

See, e.g., CAA section 165(a)(4). There is no specific language in the last clause of Element C 

 

36 The discussion here of the PSD portion of Element C also applies in full to the PSD portion of Element J.

37 See, e.g., 77 FR 64737 (October 23, 2012), “Partial Approval and Partial Disapproval of Air Quality State

Implementation Plans; Nevada; Infrastructure Requirements for Ozone and Fine Particulate Matter.”
26

that restricts its application to only those provisions of CAA title I part C that pertain to the 

particular new or revised NAAQS addressed by the particular infrastructure SIP action. Because 

the scope of CAA title I part C is comprehensive (covering all pollutants subject to regulation 

under the CAA, including GHG), the EPA likewise reads the unrestricted reference to CAA 

title I part C in Element C to mean that this provision has the same scope as CAA title I part C 

itself. Thus, an infrastructure SIP submission for any one of the recently revised NAAQS must 

be “comprehensive” in that it would need to meet all CAA title I part C requirements for other 

regulated NSR pollutants as well.

The broad scope of Element C with respect to major source PSD permitting raises the 

question of how the EPA will proceed when the timing of requirements for multiple, related SIP 

submissions (e.g., for mandatory PSD SIP revisions) impacts the ability of the air agency and the 

EPA to address certain substantive issues in the infrastructure SIP submission in a reasonable 

fashion. It is appropriate for the EPA to take into consideration the timing of related 

requirements for SIP submissions in determining what an air agency can reasonably be expected

to have addressed in an infrastructure SIP submission for a NAAQS at the time when the EPA 

acts on such submission. The EPA does not consider it reasonable to interpret Element C to

require the EPA to propose to disapprove an air agency’s infrastructure SIP submission because 

the air agency had not submitted a PSD permitting program revision that was not yet due as of 

the date of EPA’s proposed action. Because it would be unreasonable to propose such a 

disapproval, the EPA likewise does not consider it reasonable to take final disapproval action

under such circumstances. In other words, the EPA interprets these CAA sections to allow the 

EPA to approve an infrastructure SIP submission for the major source PSD permitting 

subelement of Element C (and Element J) provided that the EPA has already approved or is 

simultaneously approving the air agency’s SIP submission(s)38 with respect to all structural PSD

permitting program revision requirements that were due under the EPA regulations or the CAA 

on or before the date of the EPA’s proposed action on the infrastructure SIP submission. To 

adopt a different approach, by which the EPA could not act on an infrastructure SIP or at least 

 

38 These submissions may be submitted separately or together with the infrastructure SIP submission on which the 

EPA is proposing action.
27

could not approve an infrastructure SIP whenever there was any impending revision to the PSD 

permitting program regulations required by another collateral rulemaking action, would result in

regulatory gridlock and make it impracticable or impossible for the EPA to act on infrastructure 

SIPs if the EPA had recently revised its PSD permitting regulations but the submission required 

by such revisions was not yet due. The EPA believes that such an outcome would be an 

unreasonable reading of the statutory process for the infrastructure SIPs contemplated in 

sections 110(a)(1) and (2).

Consequently, the EPA generally plans to proceed as follows. The EPA may propose to 

approve an infrastructure SIP submission with respect to the major source PSD permitting 

subelement of Element C if the air agency has submitted, in a timely manner, all structural PSD 

permitting program provisions for which the SIP submission deadline has passed as of the date 

of the proposed approval.39 Subject to consideration of public comments on the proposed action, 

the EPA believes it may proceed to fully approve an infrastructure submission with respect to 

Element C if all such structural PSD permitting program submissions have been or are being 

simultaneously fully approved into the SIP. The EPA does not intend to treat any structural PSD 

permitting program requirement for which the SIP submission deadline falls after the date of the 

EPA’s proposed action on the infrastructure SIP as a required criterion for approval of the 

infrastructure SIP. The PSD permitting program revisions treated in this manner may include not 

only those related to the new or revised NAAQS whose promulgation has triggered the need for 

a new infrastructure SIP submission but also those related to any other regulated NSR pollutants 

as required by CAA title I part C and 40 CFR part 51.166.40

If an air agency lacks a PSD permitting program in its existing EPA-approved SIP 

addressing all regulated NSR pollutants, and it is already subject to a FIP, then major stationary 

 

39 Structural PSD program provisions include provisions necessary for the PSD program to address all regulated 

sources and NSR pollutants, including GHG. Structural PSD program provisions do not include provisions which 

under 40 CFR 51.166 are at the option of the air agency, such as the option for air agencies to provide 

grandfathering of complete permit applications with respect to the 2012 PM2.5 NAAQS. 

40 See, e.g., “Approval and Promulgation of Implementation Plans; Mississippi: New Source Review – Prevention of 

Significant Deterioration; Fine Particulate Matter (PM2.5) National Ambient Air Quality Standards,” 77 FR 59095 

(September 26, 2012), a recent infrastructure SIP approval action that addressed a state’s PSD SIP status with 

respect to the 2008 PM2.5 NSR Rule.
28

sources within its jurisdiction are subject to the federal PSD permitting requirements in 40 

CFR 52.21. Some air agencies are subject to a FIP for PSD permitting of all regulated NSR 

pollutants, and fewer air agencies are subject to a FIP for PSD permitting that is limited to 

particular pollutants (such as GHG). For sources subject to a pre-existing FIP for PSD 

permitting, either the EPA Regional Office issues PSD permits or, in instances where federal 

authority is delegated by the EPA Regional Office to it, the state or local air agency issues the 

PSD permits under the FIP (and tribes might be delegated in the same manner in the future). The 

EPA recognizes that some states have indicated a preference to operate under an EPAadministered PSD permitting program. Many air agencies have for some time been delegated the 

authority to implement a PSD FIP program. Other states have implemented their SIP-approved 

PSD permitting program. When an area is already subject to a FIP for PSD permitting (whether 

or not a state, local, or tribal air agency has been delegated federal authority to implement the 

PSD FIP), the air agency may choose to continue to rely on the PSD FIP to have permits issued 

pursuant to the FIP. If so, the EPA could not fully approve the infrastructure SIP submission with 

respect to Element C; however, the EPA anticipates that there would be no adverse consequences 

to the air agency or to sources from this lack of full approval of the infrastructure SIP. 

Mandatory sanctions would not apply under CAA section 179 because the failure to submit a 

PSD SIP is neither with respect to a submission that is required under CAA title I part D, nor in 

response to a SIP call under CAA section 110(k)(5). This relationship between a pre-existing FIP 

and the EPA’s action on an infrastructure SIP element is also explained in section II of this 

document. 

The EPA has maintained that the CAA allows the EPA to approve infrastructure SIP

submissions that do not implement the NSR Reform Rules promulgated mainly in 2002.

41 We 

articulated this position in a number of infrastructure SIP final actions taken in 2011, noting in 

the preambles for those actions that existing SIP provisions for PSD programs that have not 

 

41 The NSR rules have undergone a series of improvements over many years. Significant reforms were promulgated 

in a rulemaking commonly referred to as the "2002 NSR Reform Rules," which were published in the Federal 

Register at 67 FR 80186 (December 31, 2002).
29

addressed the NSR Reform Rules may be dealt with separately, outside the context of acting on a 

state’s infrastructure SIP.42

Air agencies may wish to reduce the need to amend their major source PSD rules after 

each new or revised NAAQS by writing them so that their coverage of pollutants and NAAQS

automatically updates with the promulgation of a new or revised NAAQS, and/or so that the 

specific PSD program requirements automatically update to stay matched with the federal PSD 

program requirements in 40 CFR 52.21. Depending on state or tribal law provisions, it may be 

possible to do one or both of these through the use of “rolling” incorporation by reference (IBR). 

An advantage of the rolling IBR approach is that it enables air agencies to quickly implement 

requirements of the CAA that may be immediately applicable to regulated sources upon the 

effective date of the new or revised NAAQS and before the deadline for air agencies to make 

infrastructure SIP submissions to the EPA. For example, one of the PSD program requirements is 

the requirement under section 165(a)(3) of the CAA that a permit applicant show it will not 

cause or contribute to a violation of any NAAQS. This requirement generally43 applies to any 

NAAQS in effect on the date a PSD permit decision is issued and is not deferred until an 

infrastructure SIP submission is due. Where permissible under state or tribal law, a rolling IBR 

approach is advisable to enable air agencies to implement this type of CAA requirement 

immediately upon the effective date of a NAAQS, thus ensuring that there is a mechanism in 

place for regulated sources in the state or an area of Indian country to meet CAA requirements 

resulting from a new or revised NAAQS as soon as it becomes applicable.

 

42 As one example of the preamble language that presents the EPA's position on infrastructure SIPs with respect to 

the issue of NSR Reform, see the final rule published in the Federal Register on July 13, 2011, "Approval and 

Promulgation of Air Quality Implementation Plans; Illinois; Indiana; Michigan; Minnesota; Ohio; Wisconsin; 

Infrastructure SIP Requirements for the 1997 8-Hour Ozone and PM2.5 National Ambient Air Quality Standards." 76 

FR 41075. In section II of the preamble, the EPA applied the described position to existing provisions for PSD 

programs in light of the "NSR Reform Rules" that we promulgated mainly in 2002; see 67 FR 80186 (Dec. 31, 

2002).

43 In some circumstances, the EPA has authorized “grandfathering” of pending PSD permit applications. See 78 FR 

3086, January 15, 2012.
30

Elements D(i)(I) and (II) – Section 110(a)(2)(D)(i): Interstate Pollution Transport

Each such plan shall –

(D) contain adequate provisions –

 (i) prohibiting, consistent with the provisions of this subchapter, any source or 

other type of emissions activity within the State from emitting any air pollutant in 

amounts which will –

 (I) contribute significantly to nonattainment in, or interfere with maintenance by, 

any other State with respect to any such national primary or secondary ambient 

air quality standard, or 

 (II) interfere with measures required to be included in the applicable 

implementation plan for any other State under part C of this subchapter to 

prevent significant deterioration of air quality or to protect visibility.

Section 110(a)(2)(D)(i) contains two subsections: (D)(i)(I) and (D)(i)(II).

Section 110(a)(2)(D)(i)(I) addresses any emissions activity in one state that contributes 

significantly to nonattainment, or interferes with maintenance, of the NAAQS in another 

state. The EPA sometimes refers to these requirements as prong 1 (significant 

contribution to nonattainment) and prong 2 (interference with maintenance). Neither 

prong 1 nor prong 2 is addressed in this guidance. This guidance does not modify any 

prior statements by the EPA with respect to prongs 1 and 2 and does not address, discuss, 

or in any way alter any requirements set forth in either prong. 

Element D(i)(II) requires SIPs to include provisions prohibiting any source or other type 

of emissions activity in one state from interfering with measures required of any other state to 

prevent significant deterioration of air quality or from interfering with measures required of any 

other state to protect visibility (referring to visibility in Class I areas). The EPA sometimes refers 

to these requirements under subsection 110(a)(2)(D)(i)(II) as prong 3 (interference with PSD) 

and prong 4 (interference with visibility protection). The EPA interprets section 110(a)(2) to 

require air agencies to address prong 3 and prong 4 as part of each infrastructure SIP submission.

Prong 3: Under section 110(a)(2)(D)(i)(II), SIPs would need to have provisions 

prohibiting emissions that would interfere with measures required to be in any other air agency’s 
31

SIP under part C of the CAA to prevent significant deterioration of air quality. Because part C 

requires an air agency’s PSD permitting program to address all pollutants subject to regulation 

under the CAA, the EPA interprets prong 3 to mean that the infrastructure SIP submission should 

have provisions to prevent emissions of any regulated pollutant from interfering with any other 

air agency’s comprehensive PSD permitting program, in addition to the new or revised NAAQS 

that is the subject of the infrastructure submission. Moreover, the infrastructure SIP should

address the potential for such interference by sources throughout the jurisdiction of the air 

agency.

One way to meet prong 3 (”interference with PSD”), specifically with respect to those 

in-state sources and pollutants that are subject to PSD permitting, is through an air agency’s 

confirmation in its infrastructure SIP submission that new major sources and major modifications 

are subject to a comprehensive EPA-approved PSD permitting program in the SIP that applies to 

all regulated NSR pollutants and that satisfies the requirements of the EPA’s PSD 

implementation rule(s), as discussed above for purposes of Element C. This is because in order 

to be approved by the EPA, a major source PSD permitting program would need to fully 

consider source impacts on air quality in other states.

In-state sources not subject to PSD for any one or more of the pollutants subject to 

regulation under the CAA because they are in a nonattainment area for a NAAQS related to 

those particular pollutants may also have the potential to interfere with PSD in an attainment or 

unclassifiable area of another state. The EPA cannot ignore this potential when reviewing an 

infrastructure SIP for this prong. The EPA will consider and may rely on an air agency’s EPAapproved nonattainment NSR provisions in determining whether a SIP satisfies prong 3 with 

respect to sources located in areas subject to nonattainment NSR for any one or more pollutants 
32

and thus not subject to PSD permitting for those NAAQS pollutants. 44 SIP revisions to address 

nonattainment NSR requirements for any new or revised NAAQS are, however, due on a 

separate timeframe under section 172(b) of the CAA and are not subject to the timeframe for 

submission of infrastructure SIPs under section 110(a)(1). Therefore, a fully approved 

nonattainment NSR program with respect to any previous NAAQS may generally be considered 

by the EPA as adequate for purposes of meeting the requirement of prong 3 with respect to 

sources and pollutants subject to such program. Also, if an air agency makes a submission 

indicating that it issues permits pursuant to 40 CFR part 51 appendix S in a nonattainment area 

because a nonattainment NSR program for a particular NAAQS pollutant has not yet been 

approved by the EPA for that area, that permitting program may generally be considered by the 

EPA as adequate for purposes of meeting the requirements of prong 3 with respect to sources and 

pollutants subject to such program. Such reliance for infrastructure purposes would not constitute 

approval under CAA title I part D, and the EPA will explain this in the preambles to any

proposed or final actions that rely on this rationale to support the conclusion that prong 3 is 

satisfied. 

For an air agency without an EPA-approved major source PSD program and/or, where 

required, an EPA-approved nonattainment NSR program, it may still be possible for the EPA to 

also find, given the facts of the situation, that other SIP provisions and/or physical condition are

adequate to prohibit interference with other air agencies’ measures to prevent significant 

deterioration of air quality.

Prong 4: Under section 110(a)(2)(D)(i)(II), an infrastructure SIP submission cannot be 

approved with respect to prong 4 (visibility transport) until the EPA has issued final approval of 

SIP provisions that the EPA has found to adequately address any contribution of that state's 

 

44 Refer, e.g., to a memorandum issued by William T. Harnett, Director, OAQPS/AQPD, "Guidance for State 

Implementation Plan (SIP) Submissions to Meet Current Outstanding Obligations Under Section 110(a)(2)(D)(i) for 

the 8-Hour Ozone and PM2.5 National Ambient Air Quality Standards," dated August 15, 2006. According to that 

2006 Harnett memo, in section 5, “[t]he implementation of a PSD and NNSR permitting program in each state 

serves to prevent significant deterioration in neighboring states and thus largely satisfies the requirements of 

section 110(a)(2)(D)(i)(II) of the CAA.” Nevertheless, nonattainment-related provisions, although identified in 

section 110(a)(2) of the CAA, are considered by the EPA to be outside the scope of infrastructure SIP actions, as 

discussed in section II of this guidance.
33

sources to impacts on visibility program requirements in other states. The EPA interprets this 

prong to be pollutant-specific, such that the infrastructure SIP submission need only address the 

potential for interference with protection of visibility caused by the pollutant (including 

precursors) to which the new or revised NAAQS applies. Carbon monoxide does not affect 

visibility, so an infrastructure SIP for any future new or revised NAAQS for carbon monoxide 

need only state this fact in order to meet prong 4. Significant impacts from lead (Pb) emissions 

from stationary sources are expected to be limited to short distances from the source and most, if 

not all, Pb stationary sources are located at distances from Class I areas such that visibility 

impacts would be negligible. Although Pb can be a component of coarse and fine particles, Pb 

generally comprises a small fraction of coarse and fine particles. Furthermore, when evaluating 

the extent to which Pb could impact visibility, Pb-related visibility impacts were found to be 

insignificant (e.g., less than 0.10 percent).45 Although we anticipate that Pb emissions will 

contribute only negligibly to visibility impairment in Class I areas, the air agency’s submission 

of an infrastructure SIP for a new or revised Pb NAAQS should include an explanation in 

support of the air agency’s conclusion (and, if appropriate, should include control measures in its 

submission to limit impacts in other states). 

One way in which prong 4 may be satisfied for any relevant NAAQS is through an air 

agency’s confirmation in its infrastructure SIP submission that it has an approved regional haze 

SIP that fully meets the requirements of 40 CFR 51.308 or 51.309. 40 CFR 51.308 and 51.309 

specifically require that a state participating in a regional planning process include all measures 

needed to achieve its apportionment of emission reduction obligations agreed upon through that 

process. See, for example, 40 CFR 51.308(d)(3)(ii). A fully approved regional haze SIP will 

ensure that emissions from sources under an air agency’s jurisdiction are not interfering with 

measures required to be included in other air agencies’ plans to protect visibility. However, if the 

air agency has submitted a 5-year progress report SIP that indicates that the regional haze SIP is 

deficient with respect to ensuring reasonable progress toward natural visibility conditions in a 

 

45 Memorandum from Mark Schmidt, OAQPS, “Ambient Pb’s Contribution to Class I Area Visibility Impairment,”

June 17, 2011.
34

Class I area in another state, the infrastructure SIP submission would need to explain how 

nevertheless the overall SIP satisfies prong 4. 

After the next round of regional haze SIPs become due in 2018, the EPA may find it 

appropriate to supplement the guidance provided here regarding the relationship between 

regional haze SIPs and prong 4.

A number of air agencies do not have fully approved regional haze SIPs in place and 

instead have FIPs in place, which cannot be relied upon to satisfy prong 4.

46 The presence of a 

regional haze FIP does not necessarily require disapproval of the infrastructure SIP for prong 4. 

A state air agency may elect to satisfy prong 4 by providing, as an alternative to relying on its 

regional haze SIP alone, a demonstration in its infrastructure SIP submission that emissions 

within its jurisdiction do not interfere with other air agencies’ plans to protect visibility. Such an 

infrastructure SIP submission would need to include measures to limit visibility-impairing 

pollutants and ensure that the reductions conform with any mutually agreed regional haze 

reasonable progress goals for mandatory Class I areas in other states.47

If the EPA determines the SIP to be incomplete or partially disapproves an infrastructure 

SIP submission for prong 4, a FIP obligation will be created. If a FIP or FIPs are already in effect 

that correct all regional haze SIP deficiencies, there will be no additional practical consequences 

from the partial disapproval for the affected air agency, the sources within its jurisdiction, or the 

 

46 Some approved regional haze SIPs have relied on the fact that electric generating units (EGUs) in the state must 

comply with a FIP previously promulgated by the EPA as part of the CSAPR to satisfy best achievable retrofit 

technology requirements for EGUs. In this limited way, if a regional haze SIP of this type has itself been approved 

by the EPA, it is possible for FIP provisions to be taken into account by the EPA in determining whether an 

infrastructure SIP may be approved for prong 4.

47 As examples of the possibility that an infrastructure SIP submission can satisfy prong 4 even though the regional 

haze SIP has not been fully approved, see: (i) “Approval and Promulgation of State Implementation Plans; State of 

Colorado; Interstate Transport of Pollution Revisions for the 1997 8-Hour Ozone and 1997 PM2.5 NAAQS: 

‘Interference With Visibility’ Requirement – Final Rule”, 76 FR 22036 (April 20, 2011); and (ii) “Approval and 

Promulgation of Implementation Plans; Kentucky; 110(a)(1) and (2) Infrastructure Requirements for the 2008 8-

Hour Ozone National Ambient Air Quality Standards – Final Rule,” 78 FR 14681 (March 7, 2013). In the first 

action, the EPA approved the infrastructure SIP submission with respect to prong 4 without having approved a 

regional haze SIP, based on the state’s demonstration that it does not interfere with other states’ measures to protect 

visibility through their regional haze SIPs. In the second proposed action, the EPA approved Kentucky’s submission 

with respect to prong 4 based on the partial approval of its regional haze SIP and its CSAPR SIP. 
35

EPA. The EPA will not be required to take further action with respect to prong 4 because the FIP

already in place would satisfy the requirements with respect to prong 4. In addition, unless the 

infrastructure SIP submission is required in response to a SIP call under CAA section 110(k)(5), 

mandatory sanctions under CAA section 179 would not apply because the deficiencies are not

with respect to a submission that is required under CAA title I part D. Nevertheless, the EPA 

continues to encourage all air agencies that may be subject to full or partial FIPs for regional 

haze requirements to consider adopting additional SIP provisions that would allow the EPA to 

fully approve the regional haze SIP and thus to withdraw the FIP and approve the infrastructure 

SIP with respect to prong 4.

Element D(ii) – Section 110(a)(2)(D)(ii): Interstate Pollution Abatement and International 

Air Pollution

Each such plan shall –

(D) contain adequate provisions –

 (ii) insuring compliance with the applicable requirements of sections 126 and 

115 (relating to interstate and international pollution abatement).

Element D(ii) is satisfied when an infrastructure SIP ensures compliance with the 

applicable requirements of CAA sections 126(a), 126(b) and (c), and 115. 

Interstate Pollution Abatement:

 Sec. 126. (a) Each applicable implementation plan shall –

(1) require each major proposed new (or modified) source –

 (A) subject to part C (relating to significant deterioration of air quality) or

 (B) which may significantly contribute to levels of air pollution in excess of the 

national ambient air quality standards in any air quality control region outside 

the State in which such source intends to locate (or make such modification), to 

provide written notice to all nearby States the air pollution levels of which may be 

affected by such source at least sixty days prior to the date on which 

commencement of construction is to be permitted by the State providing notice, 

and

(2) identify all major existing stationary sources which may have the impact 

described in paragraph (1) with respect to new or modified sources and provide 

notice to all nearby States of the identity of such sources not later than 

three months after the date of enactment of the Clean Air Act Amendments of 

1977.
36

Under section 126(a)(1) of the CAA, each SIP would need to contain provisions requiring 

each new or modified major source required by CAA title I part C to be subject to PSD to notify 

neighboring air agencies of potential impacts from the source. Consistent with EPA’s 

interpretation of part C with respect to the requirements of Element C, the notification 

requirements apply to potential impacts from all PSD-regulated pollutants, not only the new or 

revised NAAQS for which the infrastructure SIP submission is being made. Section 126(a)(1)

also requires that each SIP contain provisions requiring each new or modified major source to 

provide similar notification if it may significantly contribute to levels of pollution in excess of a 

NAAQS in any air quality control region outside of the state in which the source is located.

Air agencies with PSD programs that have been approved into their SIPs should already 

have a regulatory provision in place, consistent with 40 CFR 51.166(q)(2)(iv), which requires the 

permitting authority to notify air agencies whose lands may be affected by emissions from that 

source. Inasmuch as the information that the permitting authority provides to other air agencies is 

submitted by the source to the permitting authority, the EPA considers the notification by the 

permitting authority to satisfy the requirement of CAA section 126(a)(1)(A) that a new or 

modified major source subject to part C notify neighboring air agencies of its potential 

downwind impact.

A state that is subject to a FIP for its PSD program may not have an infrastructure SIP 

that satisfies Element D(ii) with respect to section 126(a)(1) of the CAA, depending on the scope 

of the gap in the SIP that led to the PSD FIP. Where some or all pollutants in a state are subject 

to a PSD FIP, the EPA may find the infrastructure SIP submission to be incomplete with respect 

to Element D(ii) and could not fully approve the infrastructure SIP submission with respect to 

Element D(ii) if the approved SIP has no other provision meeting the notification requirements 

of section 126(a)(1). Nonetheless, as noted above, the EPA anticipates that there would be no 

adverse consequences to the air agency or to sources within its jurisdiction from this lack of full 

approval. The EPA would not likely be required to take further action with respect to notification 

under this element, because the federal PSD rules should fully address the notification issue

through the requirements of 40 CFR 52.21(q) and 40 CFR 124.10(c)(vii) and thus satisfy the FIP 
37

requirement triggered by the disapproval of the infrastructure SIP.

48 In addition, unless the 

infrastructure SIP submission is required in response to a SIP call under CAA section 110(k)(5), 

mandatory sanctions under CAA section 179 would not apply because the deficiencies are not

with respect to a submission that is required under CAA title I part D.

The EPA notes that the requirement stated in CAA section 126(a)(2) was a one-time 

obligation on states that does not apply to the EPA’s review of infrastructure SIP submissions.

Interstate Pollution Abatement:

Section 126...

(b) Any State or political subdivision may petition the Administrator for a finding 

that any major source or group of stationary sources emits or would emit any air 

pollutant in violation of the prohibition of section 110(A)(2)(D)(ii) or this section. 

Within 60 days after receipt of any petition under this subsection and after public 

hearing, the Administrator shall make such a finding or deny the petition.

(c) Notwithstanding any permit which may have been granted by the State in 

which the source is located (or intends to locate), it shall be a violation of [this 

section and] the applicable implementation plan in such State –

 (1) for any major proposed new (or modified) source with respect to which a 

finding has been made under subsection (b) to be constructed or to operate in 

violation of [this section and] the prohibition of section 110(a)(2)(D)(ii) or this 

section, or 

 (2) for any major existing source to operate more than three months after such 

finding has been made with respect to it.

The Administrator may permit the continued operation of a source referred to in 

paragraph (2) beyond the expiration of such three-month period if such source 

complies with such emission limitations and compliance schedules (containing 

increments of progress) as may be provided by the Administrator to bring about 

compliance with the requirements contained in section 110(a)(2)(D)(ii) as 

expeditiously as practicable, but in no case later than three years after the date of 

such finding. Nothing in the preceding sentence shall be construed to preclude 

any such source from being eligible for an enforcement order under 

section 113(d) after the expiration of such period during which the Administrator 

has permitted continuous operation.

 

48 40 CFR part 124, including 124.10(c)(vii), provides for EPA notification to states whose lands may be affected by 

emissions from the source and applies to all federal PSD permits issued in accordance with 40 CFR 52.21.
38

Please note that the EPA has concluded that the cross-reference in CAA section 126(b) to 

CAA section 110(a)(2)(D)(ii) is a scrivener’s error and that Congress intended to refer to 

section 110(a)(2)(D)(i). See Appalachian Power Co. v. EPA, 249 F.3d -1032, 1040-44 (D.C. Cir. 

2001). Section 110(a)(2)(D)(i), in short, prohibits any source or emissions activity in a state from 

emitting any amount of air pollutant which will contribute significantly to nonattainment or 

interfere with maintenance of the NAAQS in another state. (42 U.S.C. § 7410.)

The required content of an infrastructure SIP with respect to Element D(ii) is affected by

sections 126(b) and 126(c) of the CAA only if: (1) the Administrator has, in response to a 

petition, made a finding under section 126(b) of the CAA that emissions from a source or

sources within the air agency’s jurisdiction emit prohibited amounts of air pollution relevant to 

the new or revised NAAQS for which the infrastructure SIP submission is being made; and (2) 

under section 126(c) of the CAA, the Administrator has required the source or sources to cease 

construction, cease or reduce operations, or comply with emissions limitations and compliance 

schedule requirements for continued operation. Where appropriate, the EPA recommends that an 

infrastructure SIP submission concerning section 126(c) include a statement to the following 

effect: “No source or sources within the state [or tribal area] are the subject of an active finding 

under section 126 of the CAA with respect to the particular NAAQS at issue.” Otherwise, where 

a source or sources within the air agency’s jurisdiction are subject to such a finding and there are 

substantive SIP requirements imposed by the Administrator under section 126(c) of the CAA, 

then we encourage the air agency to consult with its EPA Regional Office. 

International Air Pollution:

 Sec. 115. (a) Whenever the Administrator, upon receipt of reports, surveys or 

studies from any duly constituted international agency has reason to believe that 

any air pollutant or pollutants emitted in the United States cause or contribute to 

air pollution which may reasonably be anticipated to endanger public health or 

welfare in a foreign country or whenever the Secretary of State requests him to do 

so with respect to such pollution which the Secretary of State alleges is of such a 

nature, the Administrator shall give formal notification thereof to the Governor of 

the State in which such emissions originate. 

(b) The notice of the Administrator shall be deemed to be a finding under 

section 110(a)(2)(H)(ii) which requires a plan revision with respect to so much of 

the applicable implementation plan as is inadequate to prevent or eliminate the 

endangerment referred to in subsection (a). Any foreign country so affected by 
39

such emission of pollutant or pollutants shall be invited to appear at any public 

hearing associated with any revision of the appropriate portion of the applicable 

implementation plan.

Section 115 of the CAA authorizes the Administrator to require a state to revise 

its SIP under certain conditions to alleviate international transport into another country. 

Because of the appearance of the phrase “applicable requirements of section[]...115” in 

Element D(ii), the EPA interprets this requirement to be NAAQS-specific. That is, when

acting on an infrastructure SIP submission for a new or revised NAAQS, the EPA will 

look to whether the Administrator has made a finding with respect to emissions of the 

particular NAAQS pollutant and its precursors, if applicable. Where appropriate, the EPA 

recommends that infrastructure SIP submission requirements concerning section 115 

include a statement to the following effect: "There are no final findings under section 115 

of the CAA against this state [or tribal area] with respect to the particular NAAQS at 

issue." If there are one or more final findings under section 115 of the CAA, then we 

encourage the air agency to consult with its EPA Regional Office.

Element E – Section 110(a)(2)(E): Adequate Resources and Authority, Conflict of 

Interest, and Oversight of Local Governments and Regional Agencies

Each such plan shall –

(E) provide (i) necessary assurances that the State (or, except where the 

Administrator deems inappropriate, the general purpose local government or 

governments, or a regional agency designated by the State or general purpose 

local governments for such purpose) will have adequate personnel, funding, and 

authority under State (and, as appropriate, local) law to carry out such 

implementation plan (and is not prohibited by any provision of Federal or State 

law from carrying out such implementation plan or portion thereof), 

(ii) requirements that the State comply with the requirements respecting State 

boards under section 128, and (iii) necessary assurances that, where the State has 

relied on a local or regional government, agency, or instrumentality for the 

implementation of any plan provision, the State has responsibility for ensuring 

adequate implementation of such plan provision.
40

Subelement (i): The SIP should provide necessary assurances49 that the air agency has

adequate personnel and funding to implement the relevant NAAQS. In accordance with the 

EPA's regulations at 40 CFR part 51, subpart M (“Intergovernmental Consultation”), the 

infrastructure SIP submission should identify the organizations that will participate in 

developing, implementing, and enforcing the EPA-approved SIP provisions related to the new or 

revised NAAQS and thus require resources for doing so. The infrastructure SIP submission 

should identify the responsibilities of such organizations and include related agreements among 

the organizations. For compliance with section 110(a)(2)(E), see 40 CFR 51.240 ("General plan 

requirements"). Also, in accordance with the EPA's regulations at 40 CFR part 51, subpart O 

(“Miscellaneous Plan Content Requirements”), the infrastructure SIP submission should describe 

the resources that are available to these organizations for carrying out the SIP. Resources to be 

described should include: (1) those available to these organizations as of the date of 

infrastructure SIP submission; (2) those considered necessary during the 5 years following 

infrastructure SIP submission; and (3) projections regarding acquisition of the described 

resources. For compliance with section 110(a)(2)(E) with respect to resources, see 40 CFR 

51.280 ("Resources"). 

Further, the infrastructure SIP submission should assure that the responsible state, local, 

and/or regional agencies, or a tribal authority, have adequate authority under statutes, rules, and 

regulations to carry out SIP obligations with respect to the relevant NAAQS. See the EPA's 

regulations at 40 CFR part 51, subpart L ("Legal Authority") and subpart O. In accordance with 

the EPA's regulations at subpart L, the infrastructure SIP submission should show that the 

responsible organizations have the legal authority to carry out the provisions identified in the SIP 

submission.

 

49 As with any SIP submission, the EPA’s review can be expedited if a SIP submission for this element includes a 

detailed explanation of how the existing SIP (supplemented by any new provisions included in the submission) 

meets each of the applicable requirements of section 110(a)(2)(E)(i). This should include a description of the 

correlation between the requirements of this element and an equivalent set of statutory, regulatory, and/or nonregulatory provisions, as appropriate. When an air agency’s infrastructure submission more clearly identifies each

CAA element being met by the SIP submission and explains how it is met, the EPA can more easily determine 

whether the submission is complete and approvable with respect to that element.
41

In accordance with 40 CFR 51.231, the infrastructure SIP submission should identify the 

provisions of law or regulations that the air agency determines provide the necessary authority,

and the air agency should submit copies of those laws or regulations with the infrastructure SIP 

submission. If an official, legal copy of a particular law or regulation has already been provided 

to the EPA in an earlier SIP submission, that copy only needs to be referenced with sufficient 

specificity to avoid ambiguity, rather than a new copy submitted.50 For compliance with 

section 110(a)(2)(E) with respect to legal authority, see 40 CFR 51.230 and 40 CFR 51.231.

Having reviewed and approved air agency SIP submissions with respect with this 

element, the EPA expects that it would be unusual for air agencies to need to make SIP revisions 

regarding personnel, funding, or legal authority in order to satisfy this subelement. However, for 

any new or revised NAAQS, the air agency should explain in the infrastructure SIP submission 

how resources and personnel and legal authority are adequate and provide any additional 

assurances needed to meet changes in resource requirements by the new or revised NAAQS.

Subelement (ii): 

State Boards:

The infrastructure SIP submission (possibly in combination with earlier submissions 

already approved by the EPA) would need to include the statutory or regulatory provisions that 

impose the requirements mandated by CAA section 128 pertaining to certain boards, bodies, and 

personnel involved in approving permits or enforcement orders. Because CAA 

section 110(a)(2)(e)(ii) directs states to “provide requirements that the state comply with the 

 

50 Refer to a memorandum dated November 22, 2011, jointly from Janet McCabe, Deputy Assistant Administrator, 

Office of Air and Radiation, and Becky Weber, Director, Air and Waste Management Division, Region 7, to Air 

Division Directors, Regions 1-10, titled "Guidelines for Preparing Letters Submitting State Implementation Plans 

(SIPs) to EPA and for Preparing Public Notices for SIPs."
42

requirements respecting state boards under section 128,”51 the provisions that implement CAA 

section 128 would need to be contained within the SIP. That is, the EPA would not approve an 

infrastructure SIP submission that only provides a narrative description of existing air agency 

laws, rules, and regulations that are not approved into the SIP to address CAA section 128 

requirements. If an existing rule regarding conflict of interest and disclosure requirements has 

been adopted under the authority of a state or tribal law, the rule would need to be included in the 

SIP submission, but the authorizing law would not. If the state or tribal law is self-executing and 

there is no rule that could be included in the SIP, then the law would need to be incorporated into 

the SIP. Inclusion of an existing law in the SIP does not prevent the state legislature or tribal 

council from amending that law at a later date as a matter of state law, although eventually the 

EPA-approved SIP will need to be updated with any such amendment in order to revise the 

federally enforceable SIP. 

All air agencies are subject to the provisions of CAA section 128. However, if there is no

board or body authorized to approve permits or enforcement orders under the CAA, then a 

negative declaration to that effect may serve to satisfy the "board or body" requirements under 

paragraph (a)(1) of CAA section 128. It is the EPA’s stated interpretation that a multi-member 

board or body that has authority under state or tribal law to hear appeals of CAA permits or 

 

51 Sec. 128. (a) Not later than the date one year after the date of the enactment of 

this section, each applicable implementation plan shall contain requirements 

that –

(1) any board or body which approves permits or enforcement orders under this 

Act shall have at least a majority of members who represent the public interest 

and do not derive any significant portion of their income from persons subject to 

permits or enforcement orders under this Act, and

(2) any potential conflicts of interest by members of such board or body or the 

head of an executive agency with similar powers be adequately disclosed.

A State may adopt any requirements respecting conflicts of interest for such 

boards or bodies or heads of executive agencies, or any other entities which are 

more stringent than the requirements of (paragraphs (1) and (2), and the 

Administrator shall approve any such more stringent requirements submitted as 

part of an implementation plan.
43

enforcement orders is considered to have authority to “approve” those permits or enforcement 

orders. Accordingly, the requirements of section 128(a)(1) related to public interest and 

limitations on sources of income are applicable to such a board or body and would need to be 

met through provisions incorporated into the SIP.52,53

The provisions of section 128(a)(2), which concern disclosure of potential conflicts of 

interest, would need to be substantively met by provisions incorporated into the SIP, regardless 

of whether it is a board, some other body, or the head of an executive agency that has 

responsibility for approving permits or enforcement orders in that state or an area of Indian 

country. It is the EPA’s stated interpretation that a multi-member board or body that has 

authority under state or tribal law to hear appeals of CAA permits or enforcement orders is 

considered to have authority to “approve” those permits or enforcement orders. Accordingly, the 

requirement of section 128(a)(2) related to disclosure is applicable to such a board or body and 

would need to be met through provisions incorporated into the SIP.

In 1978, the EPA issued a guidance memorandum recommending ways air agencies 

could meet the requirements of section 128, including suggested interpretations of certain terms 

in section 128.54 EPA has not issued further guidance or regulations of general applicability on 

the subject since that time. However, as part of its actions on several infrastructure SIP 

submissions, the EPA has more recently proposed certain interpretations of section 128 as 

applied to these specific submissions, invited comment on these interpretations, and finalized its 

actions. Within those actions, EPA has thus provided additional interpretation of the terms of 

section 128 given specific facts and circumstances, consistent with the statutory requirements. 

 

52 The EPA expressed this interpretation in a proposed action on the infrastructure SIP for Arizona. June 27, 2012. 

“Partial Approval and Disapproval of Air Quality Implementation Plans; Arizona: Infrastructure Requirement for 

Ozone and Fine Particulate Matter.” 77 FR 38239. This action was finalized on November 5, 2012, 77 FR 66398.

53 “Approval and Promulgation of State Implementation Plans; Hawaii Infrastructure Requirements for the 1997 8-

Hour Ozone and the 1997 and 2006 Fine Particulate Matter National Ambient Air Quality Standards.” 77 FR 47530 

(August 9, 2012). The EPA’s action on the infrastructure SIP for Arizona referenced the proposal for this action on 

the infrastructure SIP for Hawaii.

54 See Memorandum from David O. Bickart to Regional Air Directors, "Guidance to States for Meeting Conflict of 

Interest Requirements of Section 128," Suggested Definitions, March 2, 1978.
44

See, e.g., EPA's proposed (77 FR 44555, July 30, 2012) and final (77 FR 66398, November 5, 

2012) actions on an infrastructure SIP submission from Arizona. Unlike the recommendations of 

the 1978 guidance memorandum, in this action the EPA interpreted the term “state board” to 

exclude an individual official. As in the 1978 guidance memorandum, in this action the EPA 

interpreted the requirement regarding representation of the public interest and limitations on 

income to apply to a board that does not issue permits and compliance orders but does hear 

appeals of permits and compliance orders. The EPA notes that air agencies in different 

jurisdictions may have very different organizational structures and very different allocations of 

authorities and responsibilities with respect to permits and enforcement orders. Thus, the EPA 

recommends that air agencies consult with their respective EPA Regional Offices about the most 

appropriate method for assuring that the requirements of section 110(a)(2)(E)(ii) and section 128 

are met in that jurisdiction under the relevant facts and circumstances.

Subelement (iii): The infrastructure SIP submission should provide necessary 

assurances55 that the state retains responsibility for ensuring adequate implementation of SIP 

obligations with respect to relevant NAAQS. A state may authorize a local or regional agency to 

carry out the SIP or a portion of the SIP within that agency's jurisdiction, if the SIP demonstrates 

that the local agency has the necessary legal authority. However, in these cases the infrastructure 

SIP submission needs to also provide assurances that the state air agency retains responsibility 

for ensuring adequate implementation of the SIP. Under subpart L, see 40 CFR 51.232 

("Assignment of legal authority to local agencies").

 

55 As with any SIP submission, the EPA’s review can be expedited if a SIP submission for this element includes a 

detailed explanation of how the existing SIP meets each of the applicable requirements of section 110(a)(2)(E)(i). 

This should include a description of the correlation between the requirements of this element and an equivalent set 

of statutory, regulatory, and/or non-regulatory provisions, as appropriate, that are part of the existing SIP. When an 

air agency’s infrastructure submission more clearly identifies each CAA element being met by the SIP submission 

and explains how the element is met, the EPA can more easily determine whether the submission is complete and 

approvable with respect to that element.
45

Element F – Section 110(a)(2)(F): Stationary Source Monitoring and Reporting

Each such plan shall –

(F) require, as may be prescribed by the Administrator –

 (i) the installation, maintenance, and replacement of equipment, and the 

implementation of other necessary steps, by owners or operators of stationary 

sources to monitor emissions from such sources, 

 (ii) periodic reports on the nature and amounts of emissions and emissionsrelated data from such sources, and 

 (iii) correlation of such reports by the State agency with any emission limitations 

or standards established pursuant to this Chapter, which reports shall be 

available at reasonable times for public inspection.

Subelement (i): The EPA’s rules regarding how SIPs would need to address requirements 

for source monitoring are contained in 40 CFR 51.212 (“Testing, inspection, enforcement, and 

compliance”). This EPA regulation requires SIPs to provide for a program of periodic testing and 

inspection of stationary sources, to provide for the identification of allowable test methods, and 

to exclude any provision that would prevent the use of any credible evidence of noncompliance. 

The infrastructure SIP submission should describe the air agency’s program for source testing, 

reference the statutory authority for the air agency’s program, and certify the absence of any 

provision preventing the use of any credible evidence. 

Subelement (ii): To address periodic reporting requirements, the infrastructure SIP 

submission should include air agency requirements providing for periodic reporting of emissions 

and emissions-related data by sources to the air agency, as required by the following emissions 

reporting requirements: 40 CFR 51.211 (“Emissions reports and recordkeeping”); 40 CFR 

sections 51.321 through 51.323 (“Source Emissions and State Action Reporting”); and the EPA’s 

Air Emissions Reporting Rule, 40 CFR part 51, subpart A (“Air Emissions Reporting 

Requirements”).56 We note that the section 51.321 requirement that emissions reports from states 

be made through the appropriate EPA Regional Office has been superseded in practice, as these 

data are now to be reported electronically through a centralized data portal pursuant to 40 CFR 

 

56 40 CFR sections 51.321 through 51.323 nominally address emission reporting but merely cross-reference to 

subpart A.
46

51.45(b), which refers to the website http://www.epa.gov/ttn/chief for the latest information on 

data reporting procedures. However, states should consult with the appropriate EPA Regional 

Office as they prepare and submit these data. All states have existing periodic source reporting of 

emissions and emission inventory reporting practices. Thus for any new or revised NAAQS, the 

infrastructure SIP may be able to certify existing authority and commitments and provide any 

additional assurance needed to meet changes in reporting and inventory requirements associated 

with the new or revised NAAQS.

Subelement (iii): The infrastructure SIP submission should reference and describe 

existing air agency requirements that have been approved into the SIP by the EPA, or include air 

agency requirements being newly submitted, that provide for the following: (1) correlation57 by 

the air agency of emissions reports by sources with applicable emission limitations or standards;

and (2) the public availability of emission reports by sources. Under 40 CFR part 51 subpart G, 

40 CFR 51.116 ("Data availability"), contains the requirements for correlating data. Correlation 

with applicable emissions limitations or standards is relevant only for those reports of source 

emissions that reflect the test method(s) and averaging period(s) specified in applicable emission 

limitations or standards. Thus, source reports of annual, ozone season, or summer day emissions 

used by the air agency to create the annual and triennial emission inventory submission to the 

EPA under 40 CFR part 51 subpart A in general would not need to be correlated with specific 

emission limitations or standards, as many sources do not have applicable emission limitations 

defined for those averaging periods. However, if the sources have applicable emissions 

limitations that are defined for these averaging periods, then they would need to be correlated.

 

57 As defined in 40 CFR 51.116(c), the term "correlated" means "presented in such a manner as to show the 

relationship between measured or estimated amounts of emissions and the amounts of such emissions allowable 

under the applicable emission limitations or other measures."
47

Element G – Section 110(a)(2)(G): Emergency Powers

Each such plan shall –

(G) provide for authority comparable to that in section 303 and adequate 

contingency plans to implement such authority.

Section 303 of the CAA provides authority to the EPA Administrator to seek a court 

order to restrain any source from causing or contributing to emissions that present an "imminent 

and substantial endangerment to public health or welfare, or the environment." The EPA has 

interpreted section 110(a)(2)(G) as imposing two basic requirements for purposes of an 

infrastructure SIP submission. 

To meet Element G requirements, the best practice for an air agency submitting an 

infrastructure SIP would be to submit, for inclusion into the SIP (if not already part of the SIP), 

the statutory or regulatory provisions that provide the air agency or official with authority 

comparable to that of the EPA Administrator under section 303 (see, e.g., 40 CFR 51.230(c)),

along with a narrative explanation of how they meet the requirements of this element.

58 If an air 

agency chooses not to include the relevant statute or regulation in its SIP, then the air agency 

should provide a reference or citation to the authority provisions, along with a narrative 

explanation of how the provisions meet the requirements of this element, as well as a copy of the 

relevant authority to accompany the SIP as required by 40 CFR 51.231.

The air agency is also required to submit, for approval into the SIP (if not already part of 

the SIP), an adequate contingency plan to implement the air agency’s emergency episode 

authority. This can be met by submitting a plan that meets the applicable requirements of 40 

CFR part 51, subpart H (40 CFR 51.150 through 51.153) (“Prevention of Air Pollution 

Emergency Episodes”) for the relevant NAAQS if the NAAQS is covered by those regulations.

The EPA’s subpart H regulations provide specific ambient levels for contingency plan 

purposes for most NAAQS. In the case of the 2006 PM2.5 NAAQS, for which the EPA has not 

 

58 The EPA recognizes that some air agencies may have general authorizing provisions that do not specifically 

enumerate specific activities but do implicitly authorize the air agency to perform such activities, in which case 

inclusion of those provisions would meet the intent of this best practice.
48

yet promulgated regulations that provide the ambient levels to classify different priority levels, 

the EPA has recommended these levels through guidance.59

Subpart H includes criteria for classification of areas into priority regions, based on 

ambient air concentrations of the particular pollutant being addressed. The currently applicable 

priority classifications for regions for each state can be found in 40 CFR part 52 subparts B 

through DDD (see sections titled “Classification of Regions”). As noted above, the air agency’s 

infrastructure SIP submission would need to include the contingency plan, if one is required and 

has not yet been approved by the EPA. If an area is classified as a Priority I, IA, or II region for a 

specified pollutant, then the infrastructure SIP should contain an emergency contingency plan 

meeting the specific requirements of 40 CFR 51.151 and 51.152, as appropriate, with respect to 

that pollutant. For such areas, the infrastructure submission should demonstrate that the air 

agency’s existing EPA-approved SIP already contains an adequate contingency plan, if that is the 

case; otherwise, the submission should include the substantive SIP revisions necessary to meet 

the emergency contingency plan requirements with respect to that pollutant.

Specifically, if an area is classified as a Priority I region for a specified pollutant, the 

area’s contingency plan (with respect to that pollutant) would need to include provisions that 

trigger actions to prevent air quality concentrations from reaching a “significant harm level” 

(SHL), which represents an imminent and substantial endangerment to public health. See 40 CFR 

51.151 and the more detailed explanation below. Each implementation plan for a Priority I, IA,

or II region would need to include a contingency plan that provides for taking certain specified 

actions. Specifically, 40 CFR sections 51.152(b) and (c) state that: 

(b) Each contingency plan for a Priority I region must provide for the following: 

(1) Prompt acquisition of forecasts of atmospheric stagnation conditions and of 

updates of such forecasts as frequently as they are issued by the National Weather 

Service. 

(2) Inspection of sources to ascertain compliance with applicable emission

control action requirements. 

 

59 See a memorandum from William T. Harnett, Director, Air Quality Policy Division, OAQPS, to Regional Air 

Division Directors, Regions I through X, “Guidance on SIP Elements Required Under Sections 110(a)(1) and (2) for 

the 2006 Fine Particle (PM2.5) National Ambient Air Quality Standards (NAAQS).” (September 25, 2009).
49

(3) Communications procedures for transmitting status reports and orders as to 

emission control actions to be taken during an episode stage, including 

procedures for contact with public officials, major emission sources, public 

health, safety, and emergency agencies and news media. 

(c) Each plan for a Priority IA and II region must include a contingency plan that 

meets, as a minimum, the requirements of paragraphs (b)(1) and (b)(2) of this 

section. Areas classified as Priority III do not need to develop episode plans.

To satisfy a Priority I, IA, or II region's contingency plan requirements under 40 CFR 

51.152(b)(1) regarding forecasts of atmospheric stagnation conditions, an infrastructure SIP 

submission may cite existing ambient monitoring and forecasting networks (such as AIRNow).60

Areas that maintain air quality at ambient levels lower that the concentrations listed in 

sections 51.150(b), (c), and (d), with respect to the pollutants listed, are classified as Priority III 

regions. These areas are subject to the requirements of CAA Element G. However, according to 

40 CFR 51.152(c), areas classified as Priority III regions are not required to develop emergency 

episode plans, which the EPA has interpreted to mean the contingency plans otherwise required 

under Element G.

In a final rulemaking signed on December 14, 2012, to revise the PM2.5 NAAQS, the 

EPA retained the pre-existing level of 500 μg/m3

, 24-hour average, for the Air Quality Index 

(AQI) value of 500 and did not establish an SHL for PM2.5.

61 In addition, there is currently no 

established SHL for Pb. For those pollutants for which there is an SHL, the SHL is an important 

part of air pollution Emergency Episode Plans. Even in the absence of an SHL, the EPA believes 

that the central components of a contingency plan would be to reduce emissions from the 

source(s) at issue (if necessary by curtailing operations of Pb or PM2.5 sources) and public 

communication as needed. In addition, if an air agency believes, based on its inventory of Pb or 

 

60 The EPA, in partnership with National Oceanic and Atmospheric Administration (NOAA), National Park Service 

(NPS), and tribal, state, and local agencies, developed the AIRNow website (see http://www.airnow.gov) to provide 

easy public access to national air quality information. The website offers daily AQI forecasts as well as real-time 

AQI conditions for over 300 cities across the U.S. and provides links to more detailed state and local air quality 

websites.

61 See 78 FR 3086 (January 15, 2013), “National Ambient Air Quality Standards for Particulate Matter.” The 

published version is posted at http://www.gpo.gov/fdsys/pkg/FR-2013-01-15/pdf/2012-30946.pdf.
50

PM2.5 sources and historic ambient monitoring data, that it does not need a more specific 

contingency plan beyond having authority to restrain any source from causing or contributing to 

an imminent and substantial endangerment, then the air agency could provide such a detailed 

rationale as part of its SIP submission. Additionally, because smoke from fires has the potential 

to be the cause of extremely high levels of PM2.5, the EPA recommends that air quality-triggered 

responses incorporated into an Emergency Episode Plan for PM2.5 be developed through a 

collaborative process working with state and tribal air quality, forestry, and agricultural agencies, 

federal land management agencies, private land managers, and the public.

An episode in which concentrations of NO2 or SO2 approach the SHL is likely to be due 

to a single facility's equipment malfunction. Accordingly, as part of a SIP to satisfy a Priority I 

region's contingency plan requirements, an infrastructure SIP submission for an NO2 NAAQS or 

an SO2 NAAQS may specify the facility-specific or equipment-specific measures to be taken in 

the event of an air pollution emergency. 

In accordance with 40 CFR 51.152(d)(1) and (2), the Administrator may either: (i)

exempt portions of a Priority I, IA, or II region that have been designated as attainment or 

unclassifiable under section 107 of the CAA from the requirements of 40 CFR 51.152 to develop 

an emergency episode contingency plans, or (ii) limit the requirements pertaining to emission 

control actions in Priority I regions to certain areas or to certain major sources. Air agencies 

interested in such an exemption or limitation in appropriate circumstances should contact their 

respective EPA Regional Offices.

Appendix L to 40 CFR part 51 provides example regulations that air agencies could use 

to develop contingency plans and inform decisions concerning air pollution emergency episodes. 

The example regulations provided in appendix L reflect generally recognized ways of preventing 

air pollution from reaching levels that would cause imminent and substantial endangerment to 

the health of persons located within affected areas. States with Priority I, IA, or II areas are 

directed by subpart H to have emergency episode contingency plans that contain alert levels for 

SO2, PM10, carbon monoxide, NO2, and ozone, but air agencies are not required to adopt the 

appendix L example regulations.
51

Element H – Section 110(a)(2)(H): SIP Revisions

Each such plan shall –

(H) provide for revision of such plan –

 (i) from time to time as may be necessary to take account of revisions of such 

national primary or secondary ambient air quality standard or the availability of 

improved or more expeditious methods of attaining such standard, and 

 (ii) except as provided in paragraph (3)(C), whenever the Administrator finds on 

the basis of information available to the Administrator that the plan is 

substantially inadequate to attain the national ambient air quality standard which 

it implements or to otherwise comply with any additional requirements 

established under this chapter.

To demonstrate that the requirements under Element H are met, the best practice for an air agency

submitting an infrastructure SIP would be to submit, for inclusion into the SIP (if not already part of the 

SIP), the statutory or regulatory provisions that provide the air agency or official with the 

authority to perform the following actions along with a narrative explanation of how they meet 

the requirements of this element: (1) revise its section 110 plan from time to time as may be 

necessary to take into account revisions of such primary or secondary NAAQS or the availability 

of improved or more expeditious methods of attaining such standards; and (2) revise the plan in 

the event the Administrator finds the plan to be substantially inadequate to attain the NAAQS or 

otherwise meet all applicable CAA requirements.62

If an air agency chooses not to include the relevant statute or regulation in its SIP, then 

the air agency should provide a reference or citation to the authority provisions, along with a 

narrative explanation of how the provisions meet the requirements of this element, as well as a 

copy of the relevant authority to accompany the SIP as required by 40 CFR 51.231. More 

information may be found under 40 CFR part 51, subpart F ("Procedural Requirements"), 

specifically, 40 CFR 51.104 ("Revisions").

 

62 The EPA recognize that some air agencies may have general authorizing provisions that do not specifically 

enumerate specific activities but do implicitly authorize the air agency to perform such activities, in which case 

inclusion of those provisions would meet the intent of this best practice.
52

Element I – Section 110(a)(2)(I): Plan Revisions for Nonattainment Areas 

Each such plan shall –

(I) in the case of a plan or plan revision for an area designated as a 

nonattainment area, meet the applicable requirements of part D of this 

subchapter (relating to nonattainment areas).

As noted earlier in this document, the EPA does not expect infrastructure SIP 

submissions to address subsection 110(a)(2)(I). The specific SIP submissions for designated 

nonattainment areas, as required under CAA title I part D, are subject to a different submission 

schedule63 than those for section 110 infrastructure elements and will be reviewed and acted 

upon through a separate process. Air agencies do not need to address Element I in an 

infrastructure SIP submission. For clarity’s sake, to better inform the public comment process on 

the SIP submission, the air agency may wish to clearly state that Element I is not being addressed

and reiterate in the infrastructure SIP submission that, according to the EPA’s interpretation of 

the CAA this element does not need to be addressed in the context of an infrastructure SIP 

submission.

Element J – Section 110(a)(2)(J): Consultation with Government Officials, Public 

Notification, and PSD and Visibility Protection

Each such plan shall –

(J) meet the applicable requirements of section 121 (relating to consultation), 

section 127 (relating to public notification), and part C (relating to prevention of 

significant deterioration of air quality and visibility protection)....

This element contains four separable sub-elements: consultation with identified officials 

on certain air agency actions; public notification; prevention of significant deterioration; and 

visibility protection.

Consultation with identified officials on certain actions:

 

63 These elements are typically referred to as nonattainment SIP or attainment plan elements and are due by the dates 

prescribed under subparts 2 through 5 of part D, extending as far as 10 years following designation for some 

elements.
53

 Sec. 121. In carrying out the requirements of this Act requiring applicable 

implementation plans to contain –

(1) any transportation controls, air quality maintenance plan requirements or 

preconstruction review of direct sources of air pollution, or 

(2) any measure referred to –

 (A) in part D (pertaining to nonattainment requirements), or

 (B) in part C (pertaining to prevention of significant deterioration), 

and in carrying out the requirements of section 113(d) (relating to certain 

enforcement orders), the State shall provide a satisfactory process of consultation 

with general purpose local governments, designated organizations of elected 

officials of local governments and any Federal land manager having authority 

over Federal land to which the State plan applies, effective with respect to any 

such requirement which is adopted more than one year after the date of 

enactment of the Clean Air Act Amendments of 1977 as part of such plan. Such 

process shall be in accordance with regulations promulgated by the 

Administrator to assure adequate consultation. The Administrator shall update as 

necessary the original regulations required and promulgated under this section 

(as in effect immediately before the date of the enactment of the Clean Air Act 

Amendments of 1990) to ensure adequate consultation. Only a general purpose 

unit of local government, regional agency, or council of governments adversely 

affected by action of the Administrator approving any portion of a plan referred 

to in this subsection may petition for judicial review of such action on the basis of 

a violation of the requirements of this section.

The infrastructure SIP submission would need to show that there is an established process 

for consultation with general-purpose local governments, designated organizations of elected 

officials of local governments, and any federal land manager having authority over federal land 

to which the plan applies, consistent with CAA section 121, which lists the specific types of 

actions for which such consultation is required. If the relevant statute is self-executing such that 

there is no associated regulation or other documents such as a memorandum of understanding, 

then the statute would need to be included in the SIP. If a regulation or other document meeting 

the CAA requirements exists, then the regulation or other document would need to be included in 

the SIP submission, and the authorizing statute should be referenced but the statute is not 

required to be part of the EPA-approved SIP. Under the requirements of 40 CFR 51.240, the SIP 

would need to identify organizations “that will participate in developing, implementing, and 

enforcing the plan and the responsibilities of such organizations.” The plan should also include 
54

any related agreements or memoranda of understanding among the organizations. See subpart M 

("Intergovernmental Consultation").

Public Notification:

Section 127. (a) Each State plan shall contain measures which will be effective to 

notify the public during any calendar [year] on a regular basis of instances or 

areas in which any national primary ambient air quality standard is exceeded or 

was exceeded during any portion of the preceding calendar year to advise the 

public of the health hazards associated with such pollution, and to enhance public 

awareness of the measures which can be taken to prevent such standards from 

being exceeded and the ways in which the public can participate in regulatory 

and other efforts to improve air quality. Such measures may include the posting of 

warning signs on interstate highway access points to metropolitan areas or 

television, radio, or press notices or information.

(b) The Administrator is authorized to make grants to States to assist in carrying 

out the requirements of subsection (a).

The infrastructure SIP submission would need to show that the air agency does the 

following: regularly notifies the public of instances or areas in which the new or revised primary

NAAQS was exceeded; advises the public of the health hazards associated with such 

exceedances; and enhances public awareness of measures that can prevent such exceedances and 

of ways in which the public can participate in regulatory and other efforts to improve air quality.

40 CFR 51.285 ("Public notification"), repeats the language of CAA section 127.

Prevention of significant deterioration: The approvability of an air agency’s PSD 

program is essential to the approvability of an infrastructure SIP submission with respect to CAA 

section 110(a)(2)(J). The requirements for Element J in relation to a comprehensive PSD 

permitting program are the same as described earlier in this document with respect to Element C. 

Generally, every PSD-related requirement of Element C applies, including the requirement that 

the PSD permitting program address all regulated pollutants. Please refer to that section. 

Visibility protection: Under 40 CFR part 51 subpart P, implementing the visibility 

requirements of CAA title I, part C, states are subject to requirements for RAVI, new source 

review for possible impacts on air quality related values in Class I areas, and regional haze 

planning. Specific requirements stemming from these CAA sections are codified at 40 CFR 
55

part 51 subpart P. However, when the EPA establishes or revises a NAAQS, these requirements

under part C do not change. The EPA believes that there are no new visibility protection 

requirements under part C as a result of a revised NAAQS. Therefore, there are no newly 

applicable visibility protection obligations pursuant to Element J after the promulgation of a new 

or revised NAAQS. Air agencies do not need to address the visibility subelement of Element J in 

an infrastructure SIP submission. For clarity’s sake, to better inform the public comment process 

on the SIP submission, the air agency may wish to clearly state that the visibility subelement of 

Element J is not being addressed, and reiterate in the submission that according to EPA’s 

interpretation of the CAA this element does not need to be addressed.

Element K – Section 110(a)(2)(K): Air Quality Modeling and Submission of Modeling Data

Each such plan shall –

(K) provide for –

 (i) the performance of such air quality modeling as the Administrator may 

prescribe for the purpose of predicting the effect on ambient air quality of any 

emissions of any air pollutant for which the Administrator has established a 

national ambient air quality standard, and 

 (ii) the submission, upon request, of data related to such air quality modeling to 

the Administrator.

To meet Element K, the best practice would be for an air agency to submit, for inclusion 

into the SIP (if not already part of the SIP), the statutory or regulatory provisions that provide the 

air agency or official with the authority to perform the following actions along with a narrative 

explanation of how the provisions meet the requirements of this element64: (1) conduct air 

quality modeling to predict the effect on ambient air quality of any emissions of any air pollutant 

for which a NAAQS has been promulgated, and (2) provide such modeling data to the EPA 

Administrator upon request.

 

64 The EPA recognizes that some air agencies may have general authorizing provisions that do not specifically 

enumerate specific activities but do implicitly authorize the air agency to perform such activities, in which case 

inclusion of those provisions would meet the intent of this best practice.
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If an air agency chooses not to include the relevant statute or regulations in its SIP, then 

the air agency should provide a reference or citation to the authority provisions, along with a 

narrative explanation of how they meet the requirements of this element, as well as a copy of the 

relevant authority to accompany the SIP as required by 40 CFR 51.231. 

Element L – Section 110(a)(2)(L): Permitting Fees

Each such plan shall –

(L) require the owner or operator of each major stationary source to pay to the 

permitting authority, as a condition of any permit required under this chapter, a 

fee sufficient to cover –

 (i) the reasonable costs of reviewing and acting upon any application for such a 

permit, and 

 (ii) if the owner or operator receives a permit for such source, the reasonable 

costs of implementing and enforcing the terms and conditions of any such permit 

(not including any court costs or other costs associated with any enforcement 

action),

until such fee requirement is superseded with respect to such sources by the 

Administrator's approval of a fee program under subchapter V of this chapter.

Currently, every state has an EPA-approved fee program under CAA title V. However, 

this fee program is not required to be part of the EPA-approved SIP. The infrastructure SIP 

should provide citations to the regulations providing for collection of permitting fees under the 

state’s EPA-approved Title V permit program. These citations to the EPA-approved title V 

regulations will not cause the title V program to be treated as part of the EPA-approved SIP, and 

the EPA will not re-review the title V program itself in the context of reviewing infrastructure 

SIP submissions. See 40 CFR 70.9 ("Fee determination and certification") and 40 CFR part 70, 

appendix A ("Approval Status of State and Local Operating Permits Programs"). If the state 

title V program fees cover all CAA permitting, implementation, and enforcement for new and 

modified major sources as well as existing major sources, this reference to the title V program 

will satisfy this element. If a state’s approved title V permit program fees do not cover the 

reasonable costs of reviewing and acting upon applications for PSD and NNSR permits for major 
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sources65 (along with the reasonable costs of implementing and enforcing the terms and 

conditions of PSD and NNSR permits), then the air agency should contact its Regional Office 

regarding what needs to be in the submission to fulfill this Element.

Element M – Section 110(a)(2)(M): Consultation and Participation by Affected Local 

Entities

Each such plan shall –

(M) provide for consultation and participation by local political subdivisions 

affected by the plan.

To satisfy Element M, the SIP should provide for consultation with affected local 

political subdivisions. As part of an infrastructure SIP submission, an air agency may simply 

identify its policies or procedures that allow and promote such consultation. For example, the 

infrastructure SIP submission may cite a policy wherein the air agency, before adopting or 

amending a plan, policy, or program, will consult with the regional planning coalition composed 

of local political subdivisions potentially affected by the action and explain how such 

information is used in the development of a SIP submission to the EPA for approval into the SIP. 

The normal public hearing process prior to adoption and submission of a SIP revision may also 

be cited as a component of the provisions for consultation, since leaders of political subdivisions 

have the opportunity to participate in that public process.

For Further Information

If you have any questions concerning this guidance, please contact Mr. H. Lynn Dail, by 

telephone at (919) 541-2363, or by email at dail.lynn@epa.gov, or Ms. Lisa Sutton, by telephone 

at (919) 541-3450 or by email at sutton.lisa@epa.gov.

 

65 Substantive NNSR provisions will not be reviewed as part of the EPA’s action on the infrastructure SIP 

submission. See discussion in Section II, “Which elements of CAA 110(a)(2) affect infrastructure SIPs?”