## Technical Support Document

Evaluation of the Arizona Infrastructure SIP for

2008 O 3 

## Transport (CAA 110(a)(2)(D))

Evaluation of the Arizona Infrastructure State Implementation Plan for the 2008 Ozone (O 3 ) NAAQS for CAA 110(a)(2)(D) Prongs 1, 2, and 4

U.S. EPA, Region 9

March 15 , 20161

Introduction This document summarizes the U.S. Environmental Protection Agency’s (EPA ’s ) review of the Arizona State Implementation Plan (SIP) provisions and local provisions to meet the requirements of §110(a) (2) (D) of the Clean Air Act (CAA) for the 2008 ozone National Ambient Air Quality Standard (NAAQS). Specifically, this Technical Support Document (TSD) examines

information submitted by the Arizona Department of Environmental Quality (ADEQ) on behalf of ADEQ, Maricopa County Air Quality Department (MCAQD or Maricopa County), Pima County Department of Environmental Quality (PDEQ or Pima County), and Pinal County Air Quality Control Dist rict (PCAQCD or Pinal County) to EPA in 2012 and 2015

.

On December 27, 2012, ADEQ submitted the “Arizona State Implementation Plan Revision under Clean Air Act Section 110(a)(2) and (2); 2008 8

- hour Ozone NAAQS” (2012 submittal) to address all of the CAA section 110(a)(2) requirements for the 2008 8

- hour Ozone NAAQS. On December 3, 2015 ADEQ submitted a supplemental submittal that included analysis for
“infrastructure” SIP (I

- SIP) elements related to several different NAAQS , incl uding a submission
for the 2008 ozone NAAQS for CAA § 110 (a)(2)(D)

. 1 ADEQ subsequently clarified that the portion of the submittal related to the 2008 ozone NAAQS only applied to prongs 1, 2, and 4. 2 For the purposes of this action, we will refer to this as the “ 2015 submittal

. ”

1 Arizona State Implementation Plan Revi sions for 2008 Ozone and 2010 Nitrogen Dioxide Under Clean Air Act Section 110(a)(2)(D) and Revision for All Previous and Future NAAQS Under CAA Section 110(a)(2)(K) signed
Decembe r 3, 2015.

2 Email from Heidi Haggerty of ADEQ to Maeve Clancy of EPA Region 9 . “ AZ 2015 Ozone Transport I

- SIP
Submittal Clarification .” S ent December 9, 2015.2

Evaluation Summary

Element Identification Meets Requirement? Element SubElement

Description ADEQ Maricopa County Pima County Pinal County

D i Interstate transport

- significant

contribution to nonattainment (prongs

1

- 2) YES

Interstate transport

- interference with maintenance (prong 3) NO ACTION Previous Approval/Disapproval

Interstate transport

- visibility transport (prong 4) N O (Regional Haze FIP)

ii Interstate pollution abatement (§126, including requirement to notify states of potential impacts from new sources) NO ACTION Previous Approval/Disapproval

International air pollution (§115) NO ACTION Previous Approval

Background
CAA section s 110(a)(1) and (2) requires states to address basic SIP requirements to implement, maintain and enforce the NAAQS no later than three years after the promulgation of a new or revised standard. Section 110(a)(2) outlines the specific requirements that each state is required to address in this SIP submission that collectively constitute the "infrastructure" of a state's air quality management program. SIP submittals that address these requirements are referred to as “infrastructure SIPs” (I

- SIP)

. In particula r, CAA section 110(a)(2)(D)(i)(I) requires that each SIP for a new or revised NAAQS contain adequate provisions to prohibit any source or other type of emissions activity within the state from emitting air pollutants that will “contribute significantly

to nonattainment” (prong 1) or “interfere with maintenance” (prong 2) of the applicable air quality standard in any other state. CAA section 110(a)(2)(D)(i)(II) requires SIP provisions that prevent interference with measures required to be included in the app licable implementation plan for any other State under part C to prevent significant deterioration of air quality (prong 3) or to protect visibility (prong 4). This action address the section 110(a)(2)(D)(i) requirements of prongs 1, 2 and 4 with respect to Arizona’s SIP submissions.

On March 27, 2008, EPA issued a revised NAAQS for 8

- hour ozone

. 3 This action triggered a requirement for states to submit an infrastructure SIP to address the applicable requirements of section 110(a)(2) within three years of i ssuance of the revised NAAQS. On December 27, 2012,

3 National Ambient Air Quality Standards for Ozone; Final Rule, 73 FR 16436 (March 27, 2008 ).3

ADEQ submitted the 2012 Ozone I

- SIP (2012 submittal) which included the SIP revision, completeness checklist, copies of authorizing statutes, and copies of public process
documentation.

On September 13, 2013, EPA issued “Guidance o n Infrastructure State Implementation Plan (SIP) Elements under Clean Air Act Sections 110(a)(1) and 110(a)(2),” which provides “advice on the development of infrastructure SIPs for the 2008 ozone NAAQS . . . as well as
infrastr ucture SIPs for new or revised NAAQS promulgated in the future.” 4 EPA followed that guidance with an additional memo specific to 110(a)(2)(D) (i)(I) (prongs 1 and 2) requirements
for the 2008 ozone standard on January 22, 2015 entitled, “Information on the Interstate Transport “Good Neighbor” Provision for the 2008 Ozone NAAQS Under CAA Section 110(a)(2)(D)(i)(I) ” (2015 transport memo). 5 While this memo did not provide specific guidance

to western states on interstate transport, it did contain preliminary mo deling information for

western states

. This 2015 transport memo, following the approach used in EPA’s prior Cross

State Air Pollution Rule (CSAPR)

, 6 provided data identifying ozone monitoring sites that were projected to be in nonattainment or have maintenance problems for the 2008 ozone NAAQS in
2018 . Also, EPA provided the projected contribution estimates from 2018 anthropogenic oxides of nitrogen (NO X ) and volatile organic compound (VOC) emissions in each state to ozone

conce ntrations t o each of the projected sites.

On August 4, 2015, EPA published a Federal Register Notice entitled, “ Notice of Availability of the Environmental Protection Agency's Updated Ozone Transport Modeling Data for the 2008 Ozone NAAQS.” 7 This Notice of Data Availability (NODA) is an update of the preliminary air quality modeling data that was released January 22, 2015. The NODA provided data identifying ozone monitoring sites that are projected to be nonattainment or have maintenance prob lems (following the CSAPR approach) for the 2008 ozone NAAQS in 2017

. 8 Also, EPA provided the projected ozone contribution estimates from 2017 anthropogenic NO X and VOC emissions in each state to ozone concentrations at each of the projected monitoring sites. The 2017 modeling released in the NODA was used to support EPA’s proposed update to CSAPR to address CAA section 110(a)(2)(D)(i)(I) requirements with respect to the 2008 ozone NAAQS in the eastern
U.S. (“CSAPR Update Rule”). 9 CSAPR and its predecess or transport rules, the NO X SIP Call and CAIR, were designed to address the collective contributions from the 37 states in the eastern
U.S. ; ozone contribution information was not calculated to or from the 11 states in the western
U.S. The proposed CSAPR U pdate Rule and the supportive modeling released in the NODA include data relevant to the West but do not evaluate potential interstate transport impacts in 11 western states, including Arizona. In this action today, we are utilizing this data to evaluate t he state’s submittals and any interstate transport obligations under section 110(a)(2)(D)(i)(I).

4 Memorandum from Stephen D. Page, Director, Office of Air Quality Planning and Standards, to Regional Air Division Directors, Regions 1

- 10 (September 13, 2013).

5 Memorandum from Stephen D. Page, Director, Office of Air Quality Planning and Standards, to Re gional Air Division Directors, Regions 1

- 10 (January 22, 2015).

6 Cross

- State Air Pollution Rule, 76 Fed. Reg. 48208 (Aug. 8, 2011).

7 Notice of Availability of the Environmental Protection Agency's Updated Ozone Transport Modeling Data for the
2008 Ozone National Ambient Air Quality Standard (NAAQS) , 80 FR 46271 (August 4, 2015).

8 EPA adopted 2017 as the analytic year for the updated ozone modeling information. See 80 FR 46273.

9 Cross

- State Air Pollution rule Update for the 2008 Ozone NAAQS , 80 FR 75706 ( December 3 , 2015).4

EPA is obligated, pursuant to a judgement issued by the Northern District of California in Sierra
Club vs. McCarthy , to take final action on 110(a)(2)(D) pron gs 1, 2, and 4 of Arizona’s December 27, 2012 SIP revision by June 7, 2016. 10 In our July 2015 partial approval and partial disapproval of the 2008 lead and ozone NAAQS for I

- SIP elements C, D, J, and K

, EPA partially approved and partially disapproved Arizona for 11 0(a)(2)(D)(i) prong 3 and partially approved and partially disapproved the SIP for purposes of 110(a)(2)(D)(ii) ( relating to CAA 115 and 126). We also stated our intention to propose action on the I

- SIP for the 2008 ozone NAAQS 110(a)(2)(D)(i ) prongs 1

, 2 , and 4 in a separate action. 11 EPA subsequently took action on I

- SIP elements A, B, E

- H, L, and M for the 2008 Pb and 2008 ozone NAAQS in August 2015. 12

On December 3 , 2015, ADEQ submitted a supplement to the 2012 Ozone I

- SIP for 110(a)(2)(D) (i) prongs 1, 2, and 4

, which included additional SIP revisions reflecting the 2013 I

SIP guidance, 2015 transport memo, and 2015 NODA (2015 submittal )

. 13

We have evaluated the 2012 and 2015 submittals in relation to the infrastructure SIP requirements (or “elements”) of CAA section 110(a)(2) (D) for the 2008 Ozone NAAQS. In the following pages we discuss the requirements of the Act , summarize the State’s submittals, and present our evaluation for CAA section 110(a)(2)(D) (i) prongs 1, 2, and 4

.

CAA Section 110(a)(2)(D)

– Interstate Transport Overview Section 110(a)(2)(D) of the Act requires that each SIP “contain adequate provisions

— (i) prohibiting, consistent with the provisions of this title, 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 mainten ance 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 to prevent signific ant deterioration of air quality or to protect visibility, and (ii) insuring compliance with the applicable requirements of sections 126 and 115 (relating to interstate and international pollution abatement).”

Section 126(a) of the Act requires notificat ion to affected, nearby states of major proposed new or modified sources. Sections 126(b) and (c) pertain to petitions by affected states to EPA regarding sources violating the “interstate transport” provisions of CAA section 110(a)(2)(i).

Section 115 of the Act similarly pertains to international transport of air pollution.

With respect to the first two “prongs” of CAA section 110(a)(D)(i) (regarding significant contribution to nonattainment or interference with maintenance in any other State), EPA

10 See Judgment, Sierra Club v. McCarthy, Case 4:14

- cv

- 05091

- YGR (N.D. Cal. May 15, 2015).

11 Partial Approval and Partial Disapproval of Air Quality State Implementation Plans; Arizona; Infrastructure Requirements for Lead and Ozone. 80 FR 40905 ( July 14, 2015 )

. 12 Approval and Promulgation of State Implementation Plans; Arizona; Infrastructure Requirements for the 2008 Lead (Pb) and the 2008 8

- Hour Ozone National Ambient Air Quality Standards (NAAQS). 80 FR 47859 ( August 10, 2015 )

. 13 See footnotes 1 and 2.5

prev iously approved Arizona’s interstate transport SIP as satisfying the requirements of CAA section 110(a)(2)(D)(i)(I) for the 1997 8

- hour ozone and 1997 PM2.5 NAAQS. 14 As we stated in our July 2015 action on the 2008 O 3 I

- SIP, “ EPA is proposing action on the I

- SIP for the 2008 ozone NAAQS w ith respect to these first two prongs of CAA section 110(a)(D)(i) i n this separate rulemaking and will take final action on these SIP elements no later than June 7,

2016

. ” 15

With respect to the third “prong” of CAA section 110(a)(D)(i) (regarding interference with measures required to be included in the applicable implementation plan for any other State to prevent significant deterioration of air quality), EPA’s evaluation of the Arizona SIP for purposes of the 2008 ozone N AAQS is contained in our July 2015 partial approval and partial disapproval action

. 16 Finally, with respect to the fourth prong of CAA section 110(a)(2)(D)(i),

EPA is proposing action and will take final action no later than June 7, 2016. 17

With respect to the requirement s in CAA section 110(a)(2)(D)(ii) regarding compliance with the applicable requirements of section 126 relating to interstate pollu tion abatement, EPA previously partially approved and partially disapproved this part of the Arizona SIP in Ju ly 2015. 18 We are taking no further action on this portion of Arizona’s transport SIP in today’s action.

CAA section 115 authorizes the Administrator to require a state to revise its SIP, in the case of a belief or allegation that any air pollutant emitted in the United States causes or contributes to air pollution which may reasonably be anticipated to endan ger public health or welfare in a foreign
country. EPA previously app roved this part of the Arizona SIP for the 2008 ozone NAAQS in July 2015. 19

Summary of Arizona’s 110(a)(2)(D) Submittals
Arizona’s 2012 submittal briefly summarized the CAA requirements of sections 110(a)(2)(D)(i) and 110(a)(2)(D)(ii), but as to prongs 1, 2, and 4

, did not address the 2008 ozone NAAQS or potential transport linkages between Arizona and other states.

Arizona’s 2015 submittal represents ADEQ’s comprehensive a nalysis of ozone transport from Arizona to surrounding states and discusses potential interstate transport linkage s between
Arizona and the El Centro and Los Angeles, CA nonattainment receptors that were identified in
the 2015 ozone transport memo and /or t he 2015 NODA. The 2015 submittal also addresses the requirements of prong 4 (interstate transport visibility requirements).

14 Approval and Promulgation of Implementation Plans; States of Arizona and Nevada; Interstate Transport of Pollution, 72 FR 41629 (July 31, 2007).

15 See footnote 11

. 16 Id.

17 See footnote 10

. 18 See footnote 11

. 19 Id.6

Consistent with the 2015 NODA, Arizona notes that its impact on the El Centro and Los Angele s monitor s is above 1%. However, Arizona only potentially impacts on e of seven Los Angeles monitors, and contributes less than 1% to all other maintenance and nonattainment receptors. ADEQ also states that, “In eastern states, the EPA has chosen a 1% of the standard threshold as a signifi cant contribution. However, Arizona considers the southwest to be different.” T hey go on to say that, “It is unclear at this point what threshold is significant for southwestern states.”
EPA’s assessment of these statements is in the next section.

ADEQ th en summarizes sources of volatile organic compounds ( VOCs ) and nitrogen oxides ( NOx ) statewide, aggregated from the 2011 National Emission Inventory . Biogenic contributions
and fires are the large non

- an thropogenic sector of VOC emissions with mobile sourc es, solvents, and gas stations as the largest anthropogenic sector. Electric generating units (EGUs), airports, and miscellaneous source categories are the largest point source contributors. For NOx, mobile sources, EGUs, and fires are the highest contribu tors. Airports and Portland cement operations are also large point sources of NOx emissions in the state.

Arizona outlines the controls on anthropogen ic emission sources in Arizona in the narrative and
in tables included as Appendix B . They focus on their efforts to reduce NOx as a precursor pollutant for downwind ozone through controls implemented through Ariz ona's Regional Haze
SIP and EPA's Regional Haze FIP and Maricopa County stationary source rules included in the
Arizona SIP . The Regional Haze Rule controls NOx emissions from smelters, cement plants, and
coal

- fired EGUs through Best Available Retrofit Technologies (BART) to reduce haze. The cost of control ranges from $2400

- $3400 per tons of NOx reduced for EGUs and $800

- $1100 per ton for cement kilns. Maricopa County is the most populous county in the state and has controls in place on many different NOx and VOC source categories including EGUs, gas stations, and various industrial processes, amongst others . Maricopa County was recent ly reclassified as a moderate nonattainment area for the 2008 ozone NAAQS

, 20 and is updating its NOx rules to meet Reasonably Available Control Technology (RACT)

, so a more stringent level of control will be in place by January 1, 2017.

EPA’s Analysis 110(a)(2)(D) (i) (I) Prong 1 and Prong 2 CAA section 110(a)(2)(D)(i), requires SIPs to contain so called “good neighbor” provisions to prohibit certain adverse air quality effects on neighboring states due to interstate transport of pollution. There are four sub

- elements (or prongs) within CAA section 110(a)(2)(D)(i). Prongs 1

and 2 require that each SIP for a new or revised NAAQS contain adequate provisions to prohibit any source or other type of emissions activity within the state from emitting air pollutants that will “contribute significantly to nonattainment” (prong 1) or “interfere with maintenance” (prong 2) of the applicable air quality standard in a ny other state.

20 Determinations of Attainment by the Attainment Date, Extensions of the Attainment Date, and Reclassification of Several Areas Classified as Marginal for the 2008 Ozone National Ambient Air Quality Standards. 80 FR 51992 (August 27, 2015)

.7

The January 2015 transport memo modeling showed a 1.47 ppb

, or 1.96% contribution from Arizona to a monitor projected to violate the 2008 ozone NAAQS located in El Centro, CA (receptor ID: 60251003). 21 The updated ozone transport modeling released with the August 2015

NODA continued to show the transport linkage between Arizona and El Centro, CA, but this time at a slightly higher level of contribution : 1.78 ppb

, or 2.4% of the NAAQS. 22 It also showed a new linkage between Arizona and a monitor in Los Angeles, CA (receptor ID: 60379033) at a

contribution of 0 .86 ppb

, or 1.1% of the NAAQS. 23

To determine whether the CAA section 110(a)(2)(D)(i)(I) , prongs 1 and 2 requirement is satisfied, EPA first must determine whether a state's emissions will contribute significantly to
nonattainment or interfere with maintenance of a NAAQS in another state. If a state is
determined not to make such contribution or interfere with maintenance of the NAAQS , then EPA can conclude that the state’s SIP complies with the requirements of section 110(a)(2)(D)(i)(I) . In several prior federal rulemakings interpreting section 110(a)(2)(D)(i)(I), EPA has evaluated whether a state will sig nificantly contribute to nonattainment or interfere with maintenance of a NAAQS by first identifying downwind receptors that are expected to have problems attaining or maintaining the NAAQS. 24 EPA has then determined which upwind states
contribute to these identified air quality problems in amounts sufficient to warrant further
evaluation to determine if the state can make emission reductions to reduce its contribution.
CSAPR and the proposed CSAPR Update used a screening threshold ( 1% of the NAAQS) to
ident ify such contributing upwind states warranti ng further review and analysis. EPA’s NODA used air quality modeling to evaluate contributions from upwind states to downward receptors. Applying the methodology used in CSAPR, t he NODA modeling information indic ate s that emissions from Arizona contribute amounts exceeding the CSAPR 1% threshold at two projected
downwind nonattainment sites in El Centro, California and Los Angeles, California.

EPA notes that it disagrees with ADEQ’s contention that it is unclear what screening threshold is significant for southwestern states when addressing interstate transport contributions. EPA
believes contribution from an individual state equal to or above 1 % of the NAAQS could be considered significant where the collective contribution of emissions from one or more upwind states is responsible for a considerable portion of the downwind air quality problem regardless of where the receptor is geographically lo cated. 25

Accordingly, although EPA’s modeling indicates that emissions from Arizona contribute above
the 1% threshold to two projected dow nwind air quality problems, EPA examined several factors to determine whether Arizona should be considered to significantly contribute to nonattainment

21 Air Quality Modeling Technica l Support Document for Memorandum from Stephen D. Page, Director, Office of Air Quality Planning and Standards, to Regional Air Division Directors, Regions 1

- 10 (September 13, 2013).

22 Data file with 2017 Ozone Contributions. Included in docket for: Notice of Availability of the Environmental Protection Agency's Updated Ozone Transport Modeling Data for the 2008 Ozone National Ambient Air Quality Standard (NAAQS), 80 FR 46271 (August 4, 2015).

23 Id.

24 NO
x SIP Call, Final Rule, 63 FR 57371 (October 27, 1998) ; Clean Air Interstate Rule (CAIR), Final Rule, 70 FR 25172 (May 12, 2005); Cross

- State Air Pollution Rule (CSAPR), Final Rule, 76 FR 48208 (August 8, 2011); CSAPR Update Rule, Proposed Rule, 80 FR 75706 (Dec. 3, 2015).

25 However, EPA has previously noted there may be additional criteria to evaluate regarding collective contribution of transported air pollution at certain locations in the West. See footnotes 5 and 7.8

or interfere with maintenance of the NAAQS at those sites, including the air quality and contribution modeling, receptor data, and the statewide measures reduc i ng emissions of VOCs
and NOx. EPA notes that no single piece of information is by itself dispositive of the issue for purposes of this analysis . Instead, EPA has considered the total weight of all the evidence taken together to evaluate whether Arizona sig nificant ly contribut e s to nonattainment or interfere s with
maintenance of the 2008 ozone NAAQS in those areas

.

One such factor that EPA considers relevant to determining the nature of a projected receptor’s interstate transport problem is the magnitude t ransported ozone from all upwind states collectively contributing to the air quality problem. In CSAPR and the CSAPR Update Rule,
EPA used the 1% air quality threshold to identify linkages between upwind states and downwind maintenance receptors. States wh ose contributions to a specific receptor that meet or exceed the
threshold were considered to be linked to that receptor. The linked states emissions (and available emission reductions) were then analyzed further as a second step to EPA’s contribution

anal ysis. States whose contributions to all receptors were below the 1% threshold did not require further evaluation to address interstate transport and therefore, we found those states were determined to make insignificant contributions to downwind air qualit y air quality. Therefore, the states below the threshold do not significantly contribute to nonattainment or interfere with maintenance of the NAAQS in other states. EPA used the 1% threshold in the East because prior analysis showed that, in general, nona ttainment problems result from a combined impact of relatively small individual contributions from upwind states, along with contributions from in

state sources. EPA has observed that a relatively large portion of the air quality problem at most ozone nonattainment and maintenance receptors in the East is the result of the collective contribution from a number of upwind states.

Specifically , EPA found the total upwind states’ contribution to ozone concentration (fro m linked and unlinked states) based on modeling for 2017 ranges from 17% to 67% to identified downwind air quality problems, with between 4 and 12 states each contributing above 1% to the downwind air quality problem. 26

, 27 Thus, irrespective of the 1% air qu ality threshold in the East, EPA has found that the collective contributions from upwind states represent a large portion of the ozone concentrations at projected air quality problems. Further in the East, EPA found that
the 1% threshold is appropriate to capture a high percentage of the total pollution transport affecting downwind receptors. By comparison, according to EPA’s modeling, the total upwind (linked or unlinked) states’ contribution to ozone concentration at the projected nonattainment

sites in E l Centro, California, and Los Angeles, California, is comparatively small with only one state contributing above the 1% threshold.

In particular, Arizona is the only state that contributes greater than the 1% threshold to the projected 2017 levels of the 2008 ozone NAAQS at the El Centro receptor. 28 T he total
contribution from all states to the El Centro receptor is 4.4 % of the total ozone concentration at

26 The stated range is based on the highest nonattainment or maintenance receptor in each ar ea. All nonattainment and maintenance receptors had upwind contributions of well over 17%, except for some receptors in Dallas and

Houston.

27 Memo to Docket from EPA, Air Quality Policy Division. “Contribution Analysis of Receptors in the Updated
CSAPR Pro posal.” March 10 , 2016.

28 See footnote 22.9

this receptor . Arizona is also the only state that cont ributes g reater than 1% to the projected 2017
levels of the 2008 ozone NAAQS at the Los Angeles receptor , and the total contribution from all
states is 2. 5 % of the ozone concentration at th is receptor. EPA believes that a 4.4% and 2.5%
cumulative ozone contribution from all upwind states is negligible, particularly when compared

to the relatively large contributions from upwind states in the East or in certain other areas of the West. For these reasons, EPA believes the emissions that result in transported ozone fro m upwind states have limited impacts on the projected air quality problems in El Centro, California, and Los Angeles, California , and therefore should not be treated as receptors for purposes of determining the interstate transport obligations of upwind st ates under section 110(a)(2)(D)(i)(I).

In Arizona

, the largest sources of VOC emissions are gasoline terminals, commercial cooking, fires, commercial/industrial fuel combustion, EGU fuel combustion, industrial boilers fuel combustion, residential fuel combustion, gas stations, waste disposal, solvents, ai rcraft, locomotives, non

- road equipment, and on

- road mobile sources. In Appendix B of the 2015
submittal , ADEQ lists the statewide controls and programs for these sources and they include permits that limit operations and specify controls, source specific rules, vehicle emissions testing, fuel standards, and implementation of federal programs like NSPS, NESHAPs, and NSR and PSD permitting. The state also list Maricopa County source specific rules and ordinances in addition to rules that incorporate federal NSPS and NESHAP requirements. Finally, they list NSPS rules not incorporated into the state SIP that regulate residential fuel combustion and gas stations; Regional Haze FIP controls; and federal engine, emissions, and fuel standards for
mobile sources.

The largest sources of NOx emissions statewide are fires, commercial/industrial fuel combustion, EGU fuel combustion, industrial boilers fuel combustion, residential fuel combustion, industrial processes, waste disposal, solvents, aircraft, locomotives, no n

- road equipment, and on

- road mobile sources. Similar to VOC emissions, in Appendix B of the 2015 submittal , ADEQ lists the statewide controls and programs for these sources and they include permits that limit operations and specify controls, source specif ic rules, vehicle emissions testing, fuel standards, and implementation of federal programs like NSPS, NESHAPs, and NSR and PSD permitting. They also list Maricopa County source specific rules and ordinances in addition to rules that incorporate federal NS PS and NESHAP requirements. Finally, they list NSPS rules not incorporated into the state SIP that regulate residential fuel combustion and gas stations; Regional Haze FIP controls; and federal engine, emissions, and fuel standards for mobile

sources

. Addi tionally, EPA notes that the Apache Generating Station will be retrofitting 2 units by December 5, 2017, further reducing NOx emissions

— for one, Selective Non

- Catalytic Reduction controls will be installed and the other will replace coal with pipeline natu ral gas as the primary fuel. 29

EPA finds that where Arizona contributes above 1% of the NAAQS to a projected downwind air quality problem in California

, the receptors are not significantly impacted by transported ozone from upwind states . Therefore, additi onal emission reductions from upwind states are not necessary to address interstate transport because the total collective upwind state ozone
contribution to these areas is relative ly low compared to the air quality problems typically

29 “Approval and Promulgation of Air Quality Implementation Plans; Arizona; Regional Haze State and Federal Implementation Plans; Reconsideration” Final Rules (80 FR 19220, April 10, 2015)10

addressed by the good neighbor provision. Additionally, Arizona has demonstrated that emissions from both VOC and NOx sources are going down and will continue to go down . EPA therefore believes that Arizona’s contributions to downwind receptors in California are considered ins ignificant. EPA proposes to find that Arizona does not significantly contribute to nonattainment or interfere with maintenance of the 2008 ozone NAAQS in other states.

110 (a)(2)(D)(i) (II) Prong 4 Prong 4 requires SIP provisions that prevent interfere nce with measures required to be included in the applicable implementation plan for any other State under part C to prevent significant deterioration of air quality or to protect visibility

.

EPA believes that ozone precursor emissions of NOx may contribute t o visibility impairment in

Class I areas. EPA’s 2013 I

- SIP guidance clarifies that a state can rely upon a fully EPA

approved Regional Haze SIP to satisfy the requirements of this sub

- element. Arizona’s Regional Haze SIP shows that sources in Arizona impac t visibility in Colorado (Great Sand Dunes National Monument, Mesa Verde National Park, Black Canyon of the Gunnison National Park, La Garita Wilderness, and Weminuche Wilderness), New Mexico (Bandelier National Monument, San Pedro Parks Wilderness, Pecos Wilderness, Bosque del Apache National Wildlife Reserve, and Gila Wilderness), and Utah (Zion National Park, Bryce Canyon National Park, Capitol Reef National Park, Canyonlands National Park, and Arches National Park) 30

Arizona’s Regional Haze SIP is not fully approved by EPA. Instead Arizona’s 2012 and 2015 submittals rely, in part, on regulations imposed by FIPs to address visibility impairment in Class 1 Areas caused by NOx, SO 2 , and PM. These regulations include contr ol technologies or emission limits on the following facilities: Arizona Public Service Cholla, 31 Salt River Projec t Coronado Generating Station, 32 Freeport McMoran Miami Smelter, 33 ASARCO Hayden Smelter, 34 Sundt Station Unit 4, 35 and Nelson Lime Plant Kilns 1 a nd 2

. 36 Emissions limits and control technology requirements have been implemented through the state SIP, or initially through a FIP, but then incorporated into the SIP, at AEPCO Apa che Station Units 1, 2, and 3. 37

Because Arizona ’s 2012 and 2015 submittals rely in part on FIP s to address interstate transport visibility requirements , they do not meet the requirements of prong 4 for the 2008 ozone NAAQS . However, because FIP s are already in place, no additional FIP obligation would be triggered by a final disapproval of this portion of Arizona’s infrastructure SIP. EPA will continue

30 Arizona State Implementation Plan, Regional Haze Under Section 308 of the Federal Regional Haze Rule (January 2011), section 12.4.1

. 31 FIP promulgated at 77 FR 72514 (December 5, 2012).

32 Id.

33 FIP promulgated at 79 FR 5240 (September 3, 2014).

34 Id.

35 Id.

36 Id.

37 SIP approval promulgated for Unit 1 and FIP promulgated for Units 2 and 3 at 77 FR 72511 (December 5, 2012). SIP revision for emissions limits for Unit 1 and SIP approval for Units 2 and 3 promulgated at 80 FR 19220 (April 10, 2015).11

to work with Arizona to incorporate emission limits to address the requirements of the Regional

Haze Rule into the Ari zona SIP.

Conclusion as to 110(a)(2)(D) EPA is proposing to approve the first two prongs of 110(a)(2)(D)(i) (I) for the 2008 ozone NAAQS for Arizona

. With respect to 110(a)(2)(D)(i)(II) , EPA is proposing to disapprove

Arizona’s 2012 and 2015 submittal s due to their reliance on FIPs to address interstate transport visibility requirements

. However, because FIPs are already in place, no additional FIP obligation would be triggered by a final disapproval of this portion of Arizona’s infrastructure SIP

. 38

38 EPA previously partially approved and partially disapproved the Arizona SIP for 110(a)(2)(D)(i)(I) prong 3. EPA also previously partially approved and partially disapproved the Arizona state SIP for purposes of 110(a)(2)(D)(ii).
See footnote 11

.