Technical Support Document – Sections 110(a)(2)(C), 110(a)(2)(D)(i)(II) (Prong 3) and 

110(a)(2)(J) related to Prevention of Significant Deterioration (PSD) for North Carolina

I. What is EPA’s Approach to the Review of Infrastructure State Implementation 

Plan (SIP) Submissions?

 The requirement for states to make a SIP submission of this type arises out of section 

110(a)(1). Pursuant to section 110(a)(1), states must make SIP submissions “within 3 years (or 

such shorter period as the Administrator may prescribe) after the promulgation of a national 

primary ambient air quality standard (or any revision thereof),” and these SIP submissions are to 

provide for the “implementation, maintenance, and enforcement” of such national ambient air 

quality standards (NAAQS). The statute directly imposes on states the duty to make these SIP 

submissions, and the requirement to make the submissions is not conditioned upon EPA’s taking 

any action other than promulgating a new or revised NAAQS. Section 110(a)(2) includes a list 

of specific elements that “each such plan” submission must address. 

EPA has historically referred to these SIP submissions made for the purpose of satisfying 

the requirements of section 110(a)(1) and (2) as “infrastructure SIP” submissions. Although the 

term “infrastructure SIP” does not appear in the Clean Air Act (CAA), EPA uses the term to 

distinguish this particular type of SIP submission from submissions that are intended to satisfy 

other SIP requirements under the CAA, such as “nonattainment SIP” or “attainment plan SIP” 

submissions to address the nonattainment planning requirements of part D of Title I of the CAA, 

“regional haze SIP” submissions required by EPA rule to address the visibility protection 

requirements of section 169A of the CAA, and nonattainment new source review permit program 

submissions to address the permit requirements of CAA, Title I, part D.
Section 110(a)(1) addresses the timing and general requirements for infrastructure SIP 

submissions and section 110(a)(2) provides more details concerning the required contents of 

these submissions. The list of required elements provided in section 110(a)(2) contains a wide 

variety of disparate provisions, some of which pertain to required legal authority, some of which 

pertain to required substantive program provisions, and some of which pertain to requirements 

for both authority and substantive program provisions.1 EPA therefore believes that while the 

timing requirement in section 110(a)(1) is unambiguous, some of the other statutory provisions 

are ambiguous. In particular, EPA believes that the list of required elements for infrastructure 

SIP submissions provided in section 110(a)(2) contains ambiguities concerning what is required 

for inclusion in an infrastructure SIP submission. 

The following examples of ambiguities illustrate the need for EPA to interpret some 

section 110(a)(1) and section 110(a)(2) requirements with respect to infrastructure SIP 

submissions for a given new or revised NAAQS. One example of ambiguity is that section 

110(a)(2) requires that “each” SIP submission must meet the list of requirements therein, while 

EPA has long noted that this literal reading of the statute is internally inconsistent and would 

create a conflict with the nonattainment provisions in part D of Title I of the CAA, which 

specifically address nonattainment SIP requirements.2 Section 110(a)(2)(I) pertains to 

nonattainment SIP requirements and part D addresses when attainment plan SIP submissions to 

address nonattainment area requirements are due. For example, section 172(b) requires EPA to 

 

1 For example: section 110(a)(2)(E)(i) provides that states must provide assurances that they have adequate legal 

authority under state and local law to carry out the SIP; Section 110(a)(2)(C) provides that states must have a SIPapproved program to address certain sources as required by part C of Title I of the CAA; and section 110(a)(2)(G) 

provides that states must have legal authority to address emergencies as well as contingency plans that are triggered 

in the event of such emergencies. 

2 See, e.g., “Rule To Reduce Interstate Transport of Fine Particulate Matter and Ozone (Clean Air Interstate Rule); 

Revisions to Acid Rain Program; Revisions to the NOx SIP Call; Final Rule,” 70 FR 25162, at 25163 – 65 (May 12, 

2005) (explaining relationship between timing requirement of section 110(a)(2)(D) versus section 110(a)(2)(I)).
establish a schedule for submission of such plans for certain pollutants when the Administrator 

promulgates the designation of an area as nonattainment, and section 107(d)(1)(B) allows up to 

two years or in some cases three years, for such designations to be promulgated.3 This ambiguity 

illustrates that rather than apply all the stated requirements of section 110(a)(2) in a strict literal 

sense, EPA must determine which provisions of section 110(a)(2) are applicable for a particular 

infrastructure SIP submission. 

Another example of ambiguity within section 110(a)(1) and (2) with respect to 

infrastructure SIPs pertains to whether states must meet all of the infrastructure SIP requirements 

in a single SIP submission, and whether EPA must act upon such SIP submission in a single 

action. Although section 110(a)(1) directs states to submit “a plan” to meet these requirements, 

EPA interprets the CAA to allow states to make multiple SIP submissions separately addressing 

infrastructure SIP elements for the same NAAQS. If states elect to make such multiple SIP 

submissions to meet the infrastructure SIP requirements, EPA can elect to act on such 

submissions either individually or in a larger combined action.4 Similarly, EPA interprets the 

CAA to allow it to take action on the individual parts of one larger, comprehensive infrastructure 

SIP submission for a given NAAQS without concurrent action on the entire submission. For 

 

3 EPA notes that this ambiguity within section 110(a)(2) is heightened by the fact that various subparts of part D set 

specific dates for submission of certain types of SIP submissions in designated nonattainment areas for various 

pollutants. Note, e.g., that section 182(a)(1) provides specific dates for submission of emissions inventories for the 

ozone NAAQS. Some of these specific dates are necessarily later than three years after promulgation of the new or 

revised NAAQS.

4 See, e.g., “Approval and Promulgation of Implementation Plans; New Mexico; Revisions to the New Source 

Review (NSR) State Implementation Plan (SIP); Prevention of Significant Deterioration (PSD) and Nonattainment 

New Source Review (NNSR) Permitting,” 78 FR 4339 (January 22, 2013) (EPA’s final action approving the 

structural PSD elements of the New Mexico SIP submitted by the State separately to meet the requirements of 

EPA’s 2008 PM2.5 NSR rule), and “Approval and Promulgation of Air Quality Implementation Plans; New Mexico; 

Infrastructure and Interstate Transport Requirements for the 2006 PM2.5 NAAQS,” 78 FR 4337 (January 22, 2013) 

(EPA’s final action on the infrastructure SIP for the 2006 PM2.5 NAAQS).
example, EPA has sometimes elected to act at different times on various elements and subelements of the same infrastructure SIP submission.5

Ambiguities within section 110(a)(1) and (2) may also arise with respect to infrastructure 

SIP submission requirements for different NAAQS. Thus, EPA notes that not every element of 

section 110(a)(2) would be relevant, or as relevant, or relevant in the same way, for each new or 

revised NAAQS. The states’ attendant infrastructure SIP submissions for each NAAQS 

therefore could be different. For example, the monitoring requirements that a state might need to 

meet in its infrastructure SIP submission for purposes of section 110(a)(2)(B) could be very 

different for different pollutants, because the content and scope of a state’s infrastructure SIP 

submission to meet this element might be very different for an entirely new NAAQS than for a 

minor revision to an existing NAAQS.6

EPA notes that interpretation of section 110(a)(2) is also necessary when EPA reviews 

other types of SIP submissions required under the CAA. Therefore, as with infrastructure SIP 

submissions, EPA also has to identify and interpret the relevant elements of section 110(a)(2) 

that logically apply to these other types of SIP submissions. For example, section 172(c)(7) 

requires attainment plan SIP submissions required by part D to meet the “applicable 

requirements” of section 110(a)(2); thus, attainment plan SIP submissions must meet the 

requirements of section 110(a)(2)(A) regarding enforceable emission limits and control measures 

and section 110(a)(2)(E)(i) regarding air agency resources and authority. By contrast, it is clear 

 

5 On December 14, 2007, the State of Tennessee, through the Tennessee Department of Environment and 

Conservation, made a SIP revision to EPA demonstrating that the State meets the requirements of sections 110(a)(1) 

and (2). EPA proposed action for infrastructure SIP elements (C) and (J) on January 23, 2012 (77 FR 3213) and 

took final action on March 14, 2012 (77 FR 14976). On April 16, 2012 (77 FR 22533) and July 23, 2012 (77 FR 

42997), EPA took separate proposed and final actions on all other section 110(a)(2) infrastructure SIP elements of 

Tennessee’s December 14, 2007 submission.

6 For example, implementation of the 1997 PM2.5 NAAQS required the deployment of a system of new monitors to 

measure ambient levels of that new indicator species for the new NAAQS.
that attainment plan SIP submissions required by part D would not need to meet the portion of 

section 110(a)(2)(C) that pertains to the PSD program required in part C of Title I of the CAA, 

because PSD does not apply to a pollutant for which an area is designated nonattainment and 

thus subject to part D planning requirements. As this example illustrates, each type of SIP 

submission may implicate some elements of section 110(a)(2) but not others. 

Given the potential for ambiguity in some of the statutory language of section 110(a)(1) 

and section 110(a)(2), EPA believes that it is appropriate to interpret the ambiguous portions of 

section 110(a)(1) and section 110(a)(2) in the context of acting on a particular SIP submission. 

In other words, EPA assumes that Congress could not have intended that each and every SIP 

submission, regardless of the NAAQS in question or the history of SIP development for the 

relevant pollutant, would meet each of the requirements, or meet each of them in the same way. 

Therefore, EPA has adopted an approach under which it reviews infrastructure SIP submissions 

against the list of elements in section 110(a)(2), but only to the extent each element applies for 

that particular NAAQS.

Historically, EPA has elected to use guidance documents to make recommendations to 

states for infrastructure SIPs, in some cases conveying needed interpretations on newly arising 

issues and in some cases conveying interpretations that have already been developed and applied 

to individual SIP submissions for particular elements.7 EPA most recently issued guidance for 

infrastructure SIPs on September 13, 2013 (2013 Guidance).8 EPA developed this document to 

provide states with up-to-date guidance for infrastructure SIPs for any new or revised NAAQS. 

 

7 EPA notes, however, that nothing in the CAA requires EPA to provide guidance or to promulgate regulations for 

infrastructure SIP submissions. The CAA directly applies to states and requires the submission of infrastructure SIP 

submissions, regardless of whether or not EPA provides guidance or regulations pertaining to such submissions. 

EPA elects to issue such guidance in order to assist states, as appropriate. 

8

“Guidance on Infrastructure State Implementation Plan (SIP) Elements under Clean Air Act Sections 110(a)(1) and 

110(a)(2),” Memorandum from Stephen D. Page, September 13, 2013.
Within this guidance, EPA describes the duty of states to make infrastructure SIP submissions to 

meet basic structural SIP requirements within three years of promulgation of a new or revised 

NAAQS. EPA also made recommendations about many specific subsections of section 

110(a)(2) that are relevant in the context of infrastructure SIP submissions.9 The guidance also 

discusses the substantively important issues that are germane to certain subsections of section 

110(a)(2). EPA interprets section 110(a)(1) and (2) such that infrastructure SIP submissions 

need to address certain issues and need not address others. Accordingly, EPA reviews each 

infrastructure SIP submission for compliance with the applicable statutory provisions of section 

110(a)(2), as appropriate. 

As an example, section 110(a)(2)(E)(ii) is a required element of section 110(a)(2) for 

infrastructure SIP submissions. Under this element, a state must meet the substantive 

requirements of section 128, which pertain to state boards that approve permits or enforcement 

orders and heads of executive agencies with similar powers. Thus, EPA reviews infrastructure 

SIP submissions to ensure that the state’s implementation plan appropriately addresses the 

requirements of section 110(a)(2)(E)(ii) and section 128. The 2013 Guidance explains EPA’s 

interpretation that there may be a variety of ways by which states can appropriately address these 

substantive statutory requirements, depending on the structure of an individual state’s permitting 

or enforcement program (e.g., whether permits and enforcement orders are approved by a multimember board or by a head of an executive agency). However they are addressed by the state, 

the substantive requirements of Section 128 are necessarily included in EPA’s evaluation of 

 

9 EPA’s September 13, 2013, guidance did not make recommendations with respect to infrastructure SIP 

submissions to address Section 110(a)(2)(D)(i)(I). EPA issued the guidance shortly after the U.S. Supreme Court 

agreed to review the D.C. Circuit decision in EME Homer City, 696 F.3d 7 (D.C. Cir. 2012) which had interpreted 

the requirements of section 110(a)(2)(D)(i)(I). In light of the uncertainty created by ongoing litigation, EPA elected 

not to provide additional guidance on the requirements of section 110(a)(2)(D)(i)(I) at that time. As the guidance is 

neither binding nor required by statute, whether EPA elects to provide guidance on a particular section has no 

impact on a state’s CAA obligations. 
infrastructure SIP submissions because section 110(a)(2)(E)(ii) explicitly requires that the state 

satisfy the provisions of section 128. 

As another example, EPA’s review of infrastructure SIP submissions with respect to the 

PSD program requirements in section 110(a)(2)(C), (D)(i)(II), and (J) focuses upon the structural 

PSD program requirements contained in part C and EPA’s PSD regulations. Structural PSD 

program requirements include provisions necessary for the PSD program to address all regulated 

sources and NSR pollutants, including Greenhouse Gases (GHGs). By contrast, structural PSD 

program requirements do not include provisions that are not required under EPA’s regulations at 

40 CFR 51.166 but are merely available as an option for the state, such as the option to provide 

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

the latter optional provisions are types of provisions EPA considers irrelevant in the context of 

an infrastructure SIP action.

For other section 110(a)(2) elements, however, EPA’s review of a state’s infrastructure 

SIP submission focuses on assuring that the state’s SIP meets basic structural requirements. For 

example, section 110(a)(2)(C) includes, inter alia, the requirement that states have a program to 

regulate minor new sources. Thus, EPA evaluates whether the state has an EPA-approved minor 

new source review program and whether the program addresses the pollutants relevant to that 

NAAQS. In the context of acting on an infrastructure SIP submission, however, EPA does not 

think it is necessary to conduct a review of each and every provision of a state’s existing minor 

source program (i.e., already in the existing SIP) for compliance with the requirements of the 

CAA and EPA’s regulations that pertain to such programs. 

With respect to certain other issues, EPA does not believe that an action on a state’s 

infrastructure SIP submission is necessarily the appropriate type of action in which to address 
possible deficiencies in a state’s existing SIP. These issues include: (i) existing provisions 

related to excess emissions from sources during periods of startup, shutdown, or malfunction 

(SSM) that may be contrary to the CAA and EPA’s policies addressing such excess emissions;10

(ii) existing provisions related to “director’s variance” or “director’s discretion” that may be 

contrary to the CAA because they purport to allow revisions to SIP-approved emissions limits 

while limiting public process or not requiring further approval by EPA; and (iii) existing 

provisions for PSD programs that may be inconsistent with current requirements of EPA’s “Final 

NSR Improvement Rule,” 67 FR 80186 (December 31, 2002), as amended by 72 FR 32526 (June 

13, 2007) (NSR Reform). Thus, EPA believes that it may approve an infrastructure SIP 

submission without scrutinizing the totality of the existing SIP for such potentially deficient 

provisions and may approve the submission even if it is aware of such existing provisions.11 It is 

important to note that EPA’s approval of a state’s infrastructure SIP submission should not be 

construed as explicit or implicit re-approval of any existing potentially deficient provisions that 

relate to the three specific issues just described. 

EPA’s approach to review of infrastructure SIP submissions is to identify the CAA 

requirements that are logically applicable to that submission. EPA believes that this approach to 

the review of a particular infrastructure SIP submission is appropriate, because it would not be 

 

10 Subsequent to issuing the 2013 Guidance, EPA’s interpretation of the CAA with respect to the approvability of 

affirmative defense provisions in SIPs has changed. See “State Implementation Plans: Response to Petition for 

Rulemaking; Restatement and Update of EPA’s SSM Policy Applicable to SIPs; Findings of Substantial 

Inadequacy; and SIP Calls To Amend Provisions Applying to Excess Emissions During Periods of Startup, 

Shutdown and Malfunction,” 80 FR 33839 (June 12, 2015). As a result, EPA’s 2013 Guidance (p. 21 & n.30) no 

longer represents the EPA’s view concerning the validity of affirmative defense provisions, in light of the 

requirements of section 113 and section 304.

11 By contrast, EPA notes that if a state were to include a new provision in an infrastructure SIP submission that 

contained a legal deficiency, such as a new exemption or affirmative defense for excess emissions during SSM 

events, then EPA would need to evaluate that provision for compliance against the rubric of applicable CAA 

requirements in the context of the action on the infrastructure SIP. 
reasonable to read the general requirements of section 110(a)(1) and the list of elements in 

section 110(a)(2) as requiring review of each and every provision of a state’s existing SIP against 

all requirements in the CAA and EPA regulations merely for purposes of assuring that the state 

in question has the basic structural elements for a functioning SIP for a new or revised NAAQS. 

Because SIPs have grown by accretion over the decades as statutory and regulatory requirements 

under the CAA have evolved, they may include some outmoded provisions and historical 

artifacts. These provisions, while not fully up to date, nevertheless may not pose a significant 

problem for the purposes of “implementation, maintenance, and enforcement” of a new or 

revised NAAQS when EPA evaluates adequacy of the infrastructure SIP submission. EPA 

believes that a better approach is for states and EPA to focus attention on those elements of 

section 110(a)(2) of the CAA most likely to warrant a specific SIP revision due to the 

promulgation of a new or revised NAAQS or other factors. 

For example, EPA’s 2013 Guidance gives simpler recommendations with respect to 

carbon monoxide than other NAAQS pollutants to meet the visibility requirements of section 

110(a)(2)(D)(i)(II), because carbon monoxide does not affect visibility. As a result, an 

infrastructure SIP submission for any future new or revised NAAQS for carbon monoxide need 

only state this fact in order to address the visibility prong of section 110(a)(2)(D)(i)(II).

Finally, EPA believes that its approach with respect to infrastructure SIP requirements is 

based on a reasonable reading of section 110(a)(1) and (2) because the CAA provides other 

avenues and mechanisms to address specific substantive deficiencies in existing SIPs. These 

other statutory tools allow EPA to take appropriately tailored action, depending upon the nature 

and severity of the alleged SIP deficiency. Section 110(k)(5) authorizes EPA to issue a “SIP 

call” whenever the Agency determines that a state’s SIP is substantially inadequate to attain or 
maintain the NAAQS, to mitigate interstate transport, or to otherwise comply with the CAA.12

 

Section 110(k)(6) authorizes EPA to correct errors in past actions, such as past approvals of SIP 

submissions.13 Significantly, EPA’s determination that an action on a state’s infrastructure SIP 

submission is not the appropriate time and place to address all potential existing SIP deficiencies 

does not preclude EPA’s subsequent reliance on provisions in section 110(a)(2) as part of the 

basis for action to correct those deficiencies at a later time. For example, although it may not be 

appropriate to require a state to eliminate all existing inappropriate director’s discretion 

provisions in the course of acting on an infrastructure SIP submission, EPA believes that section 

110(a)(2)(A) may be among the statutory bases that EPA relies upon in the course of addressing 

such deficiency in a subsequent action.14

II. What are the PSD Program Requirements for Infrastructure SIPs?

Section 110(a)(2)(C) has three components that must be addressed in infrastructure SIP 

submissions: enforcement, state-wide regulation of new and modified minor sources and minor 

modifications of major sources; and PSD permitting of major sources and major modifications in 

 

12 For example, EPA issued a SIP call to Utah to address specific existing SIP deficiencies related to the treatment of 

excess emissions during SSM events. See “Finding of Substantial Inadequacy of Implementation Plan; Call for Utah 

State Implementation Plan Revisions,” 74 FR 21639 (April 18, 2011). 

13 EPA has used this authority to correct errors in past actions on SIP submissions related to PSD programs. See

“Limitation of Approval of Prevention of Significant Deterioration Provisions Concerning Greenhouse Gas 

Emitting-Sources in State Implementation Plans; Final Rule,” 75 FR 82536 (December 30, 2010). EPA has 

previously used its authority under section 110(k)(6) of the CAA to remove numerous other SIP provisions that the 

Agency determined it had approved in error. See, e.g., 61 FR 38664 (July 25, 1996) and 62 FR 34641 (June 27, 

1997) (corrections to American Samoa, Arizona, California, Hawaii, and Nevada SIPs); 69 FR 67062, November 

16, 2004 (corrections to California SIP); and 74 FR 57051 (November 3, 2009) (corrections to Arizona and Nevada 

SIPs).

14 See, e.g., EPA’s disapproval of a SIP submission from Colorado on the grounds that it would have included a 

director’s discretion provision inconsistent with CAA requirements, including section 110(a)(2)(A). See, e.g., 75 FR 

42342 at 42344 (July 21, 2010) (proposed disapproval of director’s discretion provisions); 76 FR 4540 (January 26, 

2011) (final disapproval of such provisions).
areas designated attainment or unclassifiable for the subject NAAQS as required by the CAA 

title I part C (i.e., the major source PSD program). 

Section 110(a)(2)(D)(i) has two components: 110(a)(2)(D)(i)(I) and 110(a)(2)(D)(i)(II). 

Each of these components have two subparts resulting in four distinct components, commonly 

referred to as “prongs,” that must be addressed in infrastructure SIP submissions. The first two 

prongs, which are codified in section 110(a)(2)(D)(i)(I), are provisions that prohibit any source 

or other type of emissions activity in one state from contributing significantly to nonattainment 

of the NAAQS in another state (“prong 1”), and interfering with maintenance of the NAAQS in 

another state (“prong 2”). The third and fourth prongs, which are codified in section 

110(a)(2)(D)(i)(II), are provisions that prohibit emissions activity in one state interfering with 

measures required to prevent significant deterioration of air quality in another state (“prong 3”), 

or to protect visibility in another state (“prong 4”).

Section 110(a)(2)(J) has four components that must be addressed in infrastructure SIP 

submissions: 1) consultation with government officials, 2) public notification, 3) PSD, and 4)

visibility protection. 

With respect to the PSD elements of 110(C) and (J), EPA interprets the CAA to require 

each state to make, for each new or revised NAAQS, an infrastructure SIP submission that 

demonstrates that the air agency has a complete PSD permitting program meeting the current 

requirements for all regulated new source review (NSR) pollutants. The requirements of element 

110(D)(i)(II) may also be satisfied by demonstrating the air agency has a complete PSD 

permitting program correctly addressing all regulated NSR pollutants.

In order for the PSD elements of infrastructure SIP submissions to be approvable, a

state’s submission must demonstrate that all structural PSD program elements that are currently 
due under the CAA and EPA regulations are either approved into the SIP or are submitted for 

approval, in which case EPA must take final action to approve these elements before or 

simultaneously with its action on the infrastructure SIP. There are four more recent structural 

PSD program requirements that are relevant to EPA’s review of the PSD elements of the 

infrastructure SIP submissions. The EPA regulations that require these SIP revisions are: 1) the

Phase II Rule15; 2) the GHG Tailoring Rule16 as consistent with the holding in Utility Air 

Regulatory Group v. Environmental Protection Agency;

17 3) the NSR Fine Particulate Matter 

(PM2.5) Rule18; and 4) the PM2.5 PSD Increment-Significant Impact Levels (SILs)-Significant 

Monitoring Concentrations (SMC) Rule (only as it relates to PM2.5 Increments).

19

 Specific 

details on these PSD requirements can be found in the respective final rules cited above, 

however, a brief summary of each rule is provided below. 

The Phase II rule established federal NSR permitting requirements for the 

implementation of the ozone NAAQS including recognizing nitrogen oxide as an ozone 

precursor. See 70 FR 71612.

The GHG Tailoring Rule established emission thresholds for determining which new 

stationary sources and modification projects become subject to PSD permitting requirements for 

 

15

“Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard—Phase 2; Final Rule” 

(November 29, 2005, 70 FR 71612) (hereafter referred to as the “Phase II Rule”).

16

“Prevention of Significant Deterioration and Title V Greenhouse Gas (GHG) Tailoring Rule; Final Rule” (June 3, 

2010, 75 FR 31514) (hereafter referred to as the “GHG Tailoring Rule”).

17 Utility Air Regulatory Group v. Environmental Protection Agency, 134 S. Ct. 2427 (2014).

18 Implementation of the New Source Review Program for Particulate Matter Less Than 2.5 Micrometers; Final 

Rule” (May 16, 2008, 73 FR 28321) (hereafter referred to as the “NSR PM2.5 Rule”).

19 “Final Rule on the Prevention of Significant Deterioration (PSD) for Particulate Matter Less Than 2.5 

Micrometers (PM2.5) – Increments, Significant Impact Levels (SILs) and Significant monitoring Concentration 

(SMC); Final Rule” (October 20, 2010, 75 FR 64864) (hereafter referred to as the“PM2.5 PSD Increment-SILs-SMC 

Rule (only as it relates to PM2.5 Increments)”).
their GHG emissions. See 75 FR 31514. EPA notes that on June 23, 2014, the U.S. Supreme 

Court issued a decision addressing the application of PSD permitting requirements to GHG 

emissions. See Utility Air Regulatory Group v. Environmental Protection Agency, 134 S. Ct. 

2427. In that decision, the Supreme Court said that the EPA may not treat GHGs as an air 

pollutant for purposes of determining whether a source is a major source required to obtain a 

PSD permit. The Court also said that EPA could continue to require that PSD permits, otherwise 

required based on emissions of pollutants other than GHGs, contain limitations on GHG 

emissions based on the application of Best Available Control Technology (BACT).

In accordance with the Supreme Court decision, on April 10, 2015, the U.S. Court of 

Appeals for the District of Columbia Circuit (D.C. Circuit) issued an Amended Judgment 

(Coalition for Responsible Regulation, Inc. v. EPA, Nos. 09-1322, 10-073, 10-1092 and 10-

1167), vacating the regulations that implemented Step 2 of EPA’s GHG Tailoring Rule, but not 

the regulations that implement Step 1 of that rule. Step 1 of the GHG Tailoring Rule covers 

sources that are required to obtain a PSD permit based on emissions of pollutants other than 

GHGs. Step 2 applied to sources that emitted only GHGs above the thresholds triggering the 

requirement to obtain a PSD permit. The Amended Judgment preserves, without the need for 

additional rulemaking by EPA, the application of the BACT requirement to GHG emissions from 

Step 1 or “anyway” sources. With respect to Step 2 sources, the D.C. Circuit’s Amended 

Judgment vacated the regulations at issue in the litigation, including 40 CFR 51.166(b)(48)(v) 

and 40 CFR 52.21(b)(49)(v), “to the extent they require a stationary source to obtain a PSD 

permit if greenhouse gases are the only pollutant: (i) that the source emits or has the potential to 

emit above the applicable major source thresholds, or (ii) for which there is a significant 
emission increase from a modification.” The D.C. Circuit simultaneously issued its mandate, 

which means that the Coalition Amended Judgment became final and effective upon issuance.

On August 12, 2015, EPA signed a final rule that removes from the PSD regulations 

certain regulatory provisions that require a stationary source to obtain a PSD permit solely on the 

basis of the source’s GHG emissions (Step 2) and the regulations that require the EPA to 

consider further phasing-in GHG permitting requirements into the PSD. The EPA intends to 

further revise the PSD regulations to fully implement the Coalition Amended Judgment in a 

separate rulemaking. States may submit revisions to their PSD SIP program consistent with

EPA’s amended regulations whenever feasible. At this juncture, EPA is not expecting states to 

have revised their PSD programs for purposes of infrastructure SIP submissions and is only 

evaluating such submissions to assure that the state’s program correctly addresses GHGs 

consistent with the court decisions discussed above and EPA’s revised regulations.

At present, EPA has determined that the North Carolina infrastructure SIPs are sufficient 

to satisfy the PSD elements of 110(a)(2)(C), (D)(i)(II), and (J) with respect to GHGs. This is 

because the PSD permitting programs previously approved by the EPA into these SIPs continue 

to require that PSD permits issued to “anyway sources” contain limitations on GHG emissions 

based on the application of BACT. The approved North Carolina PSD permitting program still 

contains some provisions regarding Step 2 sources that are no longer necessary in light of the 

Supreme Court decision and D.C. Circuit Amended Judgment. Nevertheless, the presence of 

these provisions in the previously-approved plan does not render the infrastructure SIP 

submissions inadequate to satisfy the PSD elements of 110(a)(2)(C), (D)(i)(II), and (J). The SIP 

contains the PSD requirements for applying the BACT requirement to GHG emissions from 

“anyway sources” that are necessary at this time. The application of those requirements is not 
impeded by the presence of other previously-approved provisions regarding the permitting of 

Step 2 sources. Accordingly, the Supreme Court decision and subsequent D.C. Circuit judgment 

do not prevent EPA’s approval of the infrastructure SIPs of North Carolina as to the 

requirements of the PSD elements.

The 2008 NSR PM2.5 Rule20 and 2010 PM2.5 PSD Increment-SILs-SMC Rule (only as it 

relates to PM2.5 Increments) established NSR permitting requirements for the implementation of 

the PM2.5 NAAQS including increments pursuant to section 166(a) of the CAA to prevent 

significant deterioration of air quality in areas meeting the NAAQS. See 73 FR 28321 and 75 FR 

64864. On January 22, 2013, the D.C. Circuit, in Sierra Club v. EPA, 705 F.3d 458 (D.C. Cir. 

2013), issued a judgment that, among other things, vacated the provisions adding the PM2.5 SMC 

to the Federal regulations, at 40 CFR 51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c), that were

 

20 On January 4, 2013, the U.S. Court of Appeals, in Natural Resources Defense Council v. EPA, No. 08-1250, 2013 

WL 45653 (D.C. Cir., filed July 15, 2008) (consolidated with 09-1102, 11-1430), issued a judgment that remanded 

EPA’s 2007 and 2008 rules implementing the PM2.5 NAAQS. The court concluded that since subpart 4 of the CAA 

generally applies to coarse particulate matter (PM10), EPA should have also followed the more prescriptive subpart 4 

structure for the PM2.5 implementation rules. The court ordered EPA to repromulgate the implementation rules 

pursuant to subpart 4. Subpart 4 of part D, title 1 of the CAA establishes additional provisions for particulate matter 

nonattainment areas.

The 2008 implementation rule addressed by the court decision, “Implementation of New Source Review (NSR) 

Program for Particulate Matter Less Than 2.5 Micrometers (PM2.5),” 73 FR 28321 (May 16, 2008), promulgated 

NSR requirements for implementation of PM2.5 in both nonattainment areas (NNSR) and attainment/unclassifiable 

areas (PSD). As the requirements of subpart 4 only pertain to nonattainment areas, EPA does not consider the 

portions of the 2008 rule that address requirements for PM2.5 attainment and unclassifiable areas to be affected by 

the court’s opinion. Moreover, EPA does not anticipate the need to revise any PSD requirements promulgated in the 

2008 rule in order to comply with the court’s decision. Accordingly, EPA’s approval of a state’s infrastructure SIP 

related to elements (C), (D)(i) (prong 3), or (J) with respect to the PSD requirements promulgated in the 2008 NSR 

PM2.5 Rule does not conflict with the court’s opinion.

The court’s decision with respect to the NNSR requirements promulgated by the 2008 implementation rule also does 

not affect EPA’s action on the present infrastructure action. EPA interprets the Act to exclude nonattainment area 

requirements, including requirements associated with a NNSR program, from infrastructure SIP submissions due 

three years after adoption or revision of a NAAQS. Instead, these elements are typically referred to as 

nonattainment SIP or attainment plan elements, which would be due by the dates statutorily prescribed under subpart 

2 through 5 under part D, extending as far as 10 years following designations for some elements. 
promulgated as part of the 2010 PM2.5 PSD Increment-SILs-SMC Rule.21

 See 75 FR 64864; see

also, Sierra Club v. EPA, 705 F.3d 458 (D.C. Cir. 2013). In its decision, the court held that EPA 

did not have the authority to use SMCs to exempt permit applicants from the statutory 

requirement in section 165(e)(2) of the CAA that ambient monitoring data for PM2.5 be included 

in all PSD permit applications. Thus, although the PM2.5 SMC was not a required element of a 

state's PSD program and thus not a structural requirement for purposes of infrastructure SIPs, 

were a SIP-approved PSD program that contains such a provision to use that provision to issue 

new permits without requiring ambient PM2.5 monitoring data, such application of the SIP would 

be inconsistent with the court’s opinion and the requirements of section 165(e)(2) of the CAA. 

Because of the vacatur of the EPA regulations, the SMC provisions included in states’ SIPapproved PSD programs on the basis of EPA’s regulations are unlawful and no longer federally 

enforceable by law. Permits issued on the basis of these provisions as they appear in approved 

SIPs would be inconsistent with the CAA and difficult to defend in administrative and judicial 

challenges. Thus, the SIP provisions may not be applied even prior to their removal from the 

SIPs. States should instead require applicants requesting a PSD permit, including those having 

already been applied for but for which the permit has not yet been received, to submit ambient 

PM2.5 monitoring data in accordance with the CAA requirements whenever either direct PM2.5 or 

any PM2.5 precursor is emitted in a significant amount.22

 

21

“Prevention of Significant Deterioration (PSD) for Particulate Matter Less Than 2.5 Micrometers (PM2.5)—

Increments, Significant Impact Levels (SILs) and Significant Monitoring Concentration (SMC)”; Final Rule, 75 FR 

64864 (October 20, 2010), (hereafter referred to as the “2010 PM2.5 PSD Increment-SILs-SMC Rule”).

22

 In lieu of the applicants’ need to set out PM2.5 monitors to collect ambient data, applicants may submit PM2.5

ambient data collected from existing monitoring networks when the permitting authority deems such data to be 

representative of the air quality in the area of concern for the year preceding receipt of the application. EPA believes 

that applicants will generally be able to rely on existing representative monitoring data to satisfy the monitoring data 

requirement.
On December 9, 2013, EPA issued a final rulemaking to remove the vacated and 

remanded PM2.5 SILs23 and the vacated PM2.5 SMC provisions from 40 CFR 51.166 and 52.21.24 

See 79 FR 73698. Because the Court vacated the PM2.5 SMC provisions in 40 CFR 

51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c), EPA revised the existing concentration for the PM2.5 

SMC listed in sections 51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c) to zero micrograms per cubic 

meter (mg/m3). Were EPA to completely remove PM2.5 from the list of pollutants in sections 

51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c) of the PSD regulations, PM2.5 would no longer be a listed 

pollutant.

EPA did not entirely remove PM2.5 as a listed pollutant in the SMC provisions so as to 

avoid any potential that sections 51.166(i)(5)(iii) and 52.21(i)(5)(iii) could be interpreted as 

giving reviewing authorities the discretion to exempt permit applicants from the requirement to 

conduct monitoring for PM2.5. Such a conclusion would contravene the Court’s decision and the 

CAA.

By continuing to include PM2.5 as a pollutant in the list contained in sections 

51.166(i)(5)(i) and 52.21(i)(5)(i), with the numerical value replaced with zero mg/m3, EPA is

avoiding any concern that paragraph (iii) of the two affected sections could be applied to excuse 

permit applicants from adequately addressing the monitoring requirement for PM2.5.

EPA also advises states to begin preparations to remove the PM2.5 provisions from their 

state PSD regulations and SIPs. As the previously-approved PM2.5 SMC SIP provisions are no 

 

23 The court’s January 22, 2013, decision also vacated and remanded back to EPA the PM2.5 SILs. EPA’s December 

9, 2013 final rule also removed the PM2.5 SILs from the CFR. The PM2.5, SILs are not a required element of a 

State’s PSD program and thus not a structural requirement for purposes of infrastructure SIPs. The PM2.5 SILs are 

not approved into the SIP revisions that are the subject of this proposed rulemaking.

24 Final Rule entitled “Prevention of Significant Deterioration for Particulate Matter Less Than 2.5

Micrometers—Significant Impact Levels and Significant Monitoring Concentration: Removal of Vacated

Elements;” 79 FR 73698 (December 9, 2013)
longer enforceable, EPA does not believe the existence of these provisions in SIPs preclude 

approval of the infrastructure SIP submissions.

III. What is EPA’s Analysis of How North Carolina Addressed Sections 110(a)(2)(C), 

110(a)(2)(D)(i)(II) (prong 3) and 110(a)(2)(J) related to PSD?

As noted in section II. above, four recent structural PSD program requirements that are 

relevant to EPA’s review of the PSD elements of the infrastructure SIP submissions are the

Phase II Rule, GHG Tailoring Rule, NSR PM2.5 Rule, and PM2.5 PSD Increment-SILs-SMC Rule

(only as it relates to PM2.5 Increments). EPA approved North Carolina’s SIP revisions 

addressing the Phase II Rule on August 10, 2011 (76 FR 49313), and the GHG Tailoring Rule on 

October 18, 2011 (76 FR 64240). EPA’s latest action proposes approval of North Carolina’s SIP 

revision addressing the NSR PM2.5 Rule and partially approves and partially disapproves North 

Carolina’s SIP revision addressing the PM2.5 PSD Increment-SILs-SMC Rule. See the proposed 

rulemaking associated with docket number “EPA-R04-OAR-2015-0501” for detailed discussion 

of those actions.