Partial Approval and Partial Disapproval of Air Quality State Implementation Plans; Arizona; Infrastructure Requirements To Address Interstate Transport for the 2008 Ozone NAAQS

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

The Environmental Protection Agency (EPA) is proposing to partially approve and partially disapprove a State Implementation Plan (SIP) revision submitted by the Arizona Department of Environmental Quality on December 27, 2012, and supplemented on December 3, 2015, to address the interstate transport requirements of Clean Air Act (CAA or Act) section 110(a)(2)(D) with respect to the 2008 ozone (O₃) national ambient air quality standard (NAAQS). We are proposing to approve the portion of the Arizona SIP pertaining to significant contribution to nonattainment or interference with maintenance in another state and proposing to disapprove the portion of Arizona's SIP pertaining to interstate transport visibility requirements. EPA's rationale for proposing to partially approve and partially disapprove Arizona's December 27, 2012 SIP revision and December 3, 2015 supplement is described in this notice. EPA previously took two separate actions on Arizona's December 27, 2012 submittal, on July 14, 2015 and August 10, 2015. We are taking comments on this proposal and plan to follow with a final action no later than June 7, 2016.

DATES:

Written comments must be received on or before April 21, 2016.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R09-OAR-2015-0793 at http://www.regulations.gov,, or via email to Clancy.Maeve@epa.gov. For comments submitted at Regulations.gov, follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. For either manner of submission, the EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e. on the web, cloud, or other file sharing system). For additional submission methods, please contact the person identified in the FOR FURTHER INFORMATION CONTACT section. For the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT:

Maeve Clancy, EPA Region IX, (415) 947-4105, Clancy.Maeve@epa.gov.

SUPPLEMENTARY INFORMATION:

Throughout this document, the terms “we,” “us,” and “our” refer to EPA.

Table of Contents

I. Background

II. State Submittals

III. EPA's Assessment

IV. Proposed Action

V. Statutory and Executive Order Reviews

I. Background

CAA sections 110(a)(1) and (2) require 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 particular, 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 applicable 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 addresses the section 110(a)(2)(D)(i) requirements of prongs 1, 2 and 4 with respect to Arizona's I-SIP submissions.

On March 27, 2008, EPA issued a revised NAAQS for ozone. This action triggered a requirement for states to submit an I-SIP to address the applicable requirements of section 110(a)(2) within three years of issuance of the revised NAAQS.

On September 13, 2013, EPA issued “Guidance on 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 infrastructure SIPs for new or revised NAAQS promulgated in the future.” EPA followed that guidance with an additional memo specific to 110(a)(2)(D)(i)(I) (prongs 1 and 2) requirements for the 2008 O₃ 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). While this memo did not provide specific guidance to western states on interstate transport, it did contain preliminary modeling information for western states. This 2015 transport memo, following the approach used in EPA's prior Cross-State Air Pollution Rule (CSAPR), 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 concentrations at 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.” This Notice of Data Availability (NODA) is an update of the preliminary air quality modeling data that was released January 22, 2015. This NODA provided data identifying ozone monitoring sites that are projected to be nonattainment or have maintenance problems (following the CSAPR approach) for the 2008 ozone NAAQS in 2017. 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”). CSAPR and its predecessor 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. and ozone contribution information was not calculated to or from the 11 states in the western U.S. The proposed CSAPR Update Rule and the supportive modeling released in the NODA include data relevant to the West but did not evaluate potential interstate transport impacts in 11 western states, including Arizona. In this action, we are utilizing these data to evaluate the state's submittals and any interstate transport obligations under section 110(a)(2)(D)(i)(I).

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) prongs 1, 2, and 4 of Arizona's December 2012 SIP revision by June 7, 2016. In our July 2015 partial approval and partial disapproval of Arizona's I-SIP submittals for the 2008 Pb and 2008 ozone NAAQS, for the I-SIP elements C, D, J, and K, EPA partially approved and partially disapproved the submittals for purposes of 110(a)(2)(D)(i)(II) prong 3 and partially approved and partially disapproved the submittals for purposes of 110(a)(2)(D)(ii) (relating to CAA sections 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. We 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.

II. State Submittals

On December 27, 2012, the Arizona Department of Environmental Quality (ADEQ) submitted its 2008 ozone NAAQS I-SIP (2012 submittal). This submittal briefly summarized the CAA requirements of sections 110(a)(2)(D)(i), 110(a)(2)(D)(ii), and EPA's I-SIP action for the previous 1997 ozone NAAQS, but as to prongs 1, 2, and 4 did not identify or address any potential interstate transport impacts between Arizona and other states or interstate transport visibility requirements for the 2008 ozone NAAQS. On December 3, 2015, ADEQ submitted a supplement to the 2012 submittal addressing 110(a)(2)(D)(i) prongs 1, 2, and 4. For the purposes of this action, we will refer to the supplemental submittal as the “2015 submittal.” The 2015 submittal represents ADEQ's comprehensive analysis of ozone transport from Arizona to surrounding states and addresses potential interstate transport linkages between Arizona and the El Centro, CA and Los Angeles, CA nonattainment receptors that were identified in the 2015 ozone transport memo and the 2015 NODA. The 2015 submittal also addresses the requirements of prong 4 (interstate transport visibility requirements).

In the 2015 submittal, ADEQ summarizes the state's impact on downwind states. While Arizona's impact on the El Centro and Los Angeles monitors is in each case above 1%, Arizona impacts only one of the seven projected nonattainment or maintenance receptors in the Los Angeles area, and contributes less than 1% to all other maintenance and nonattainment receptors. ADEQ further states that, “In eastern states, the EPA has chosen a 1% of the standard threshold as a significant contribution. However, Arizona considers the southwest to be different.” The state goes on to say that, “It is unclear at this point what threshold is significant for southwestern states.” EPA's assessment of these statements is described in the next section. The submittal also summarizes sources of VOCs and NO_X statewide, outlining the controls on anthropogenic emission sources with a focus on efforts to reduce NO_X through controls implemented via Arizona's Regional Haze SIP and EPA's Regional Haze Federal Implementation Plan (FIP) and current and future Maricopa County stationary source controls in the Arizona SIP. For more information on Arizona's source categories and emissions controls, please see the technical support document (TSD) associated with today's proposed rulemaking.

III. EPA's Assessment

110(a)(2)(D)(i)(I) Prong 1 and Prong 2

EPA proposes to approve Arizona's SIP submissions pertaining to CAA section 110(a)(2)(D)(i)(I), prongs 1 and 2, with respect to the 2008 ozone NAAQS. As explained below, EPA's proposal is based on the state's submission and EPA's analysis of several factors and available data.

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 other states. 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 significantly 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. 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 identify such contributing upwind states warranting 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, the NODA modeling information indicates 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 located.

Accordingly, although EPA's modeling indicates that emissions from Arizona contribute above the 1% threshold to two projected downwind air quality problems, EPA examined several factors to determine whether Arizona should be considered to significantly contribute to nonattainment or interfere with maintenance of the NAAQS at those sites, including the air quality and contribution modeling, receptor data, and the statewide measures reducing emissions of VOCs and NO_X. 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 significantly contributes to nonattainment or interferes 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 of ozone attributable to transport 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 whose contributions to a specific receptor 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 analysis. States whose contributions to all receptors were below the 1% threshold did not require further evaluation to address interstate transport and we therefore found those states were determined to make insignificant contributions to downwind 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, nonattainment 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 (from linked and unlinked states) based on modeling for 2017 ranges from 17% to 67% to identified downwind air quality problems in the East, with between 4 and 12 states each contributing above 1% to the downwind air quality problem. Thus, irrespective of the 1% air quality 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 El Centro, California and Los Angeles, California, is comparatively small, with only one state contributing above 1% to the downwind air quality problem.

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. The total contribution from all states to the El Centro receptor is 4.4% of the total ozone concentration at this receptor. Arizona is also the only state that contributes greater 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 this 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 from 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 states under section 110(a)(2)(D)(i)(I).

Additionally, EPA has evaluated the Arizona VOC and NO_X emissions inventory and emissions projections and agrees that emissions will be decreasing over time. Given that emissions within the state are expected to decrease over time due to regional haze measures, Federal engine and fuel standards, and other Federal, State, and local rules, EPA believes that the Arizona SIP contains adequate provisions to ensure that air emissions in Arizona do not significantly contribute to nonattainment or interfere with maintenance of the 2008 ozone NAAQS in California or any other state in the future.

The modeling data show that Arizona contributes either less than 1% of the NAAQS to projected air quality problems in other states, or where it contributes above 1% of the NAAQS to a projected downwind air quality problem in California, EPA proposes to find, based on the overall weight of evidence, that these particular receptors are not significantly impacted by transported ozone from upwind states. Emissions reductions from Arizona are not necessary to address interstate transport because the total collective upwind state ozone contribution to these receptors is relatively low compared to the air quality problems typically addressed by the good neighbor provision. Additionally, Arizona has demonstrated that both VOC and NO_X emissions are going down and will continue to go down. EPA therefore believes that Arizona's contributions to downwind receptors in California are considered insignificant. 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

EPA believes that ozone precursor emissions of NO_X may contribute to 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 impact 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). 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 NO_X, SO₂, and PM. These regulations include emission limits on the following facilities: Arizona Public Service Cholla Power Plant, Salt River Project Coronado Generating Station, Freeport McMoran Miami Smelter, ASARCO Hayden Smelter, Sundt Generating Station Unit 4, and Nelson Lime Plant Kilns 1 and 2. Emissions limits have been incorporated into the state SIP, replacing a previous FIP, at AEPCO Apache Station Units 1, 2, and 3.

Because Arizona's 2012 and 2015 submittals rely in part on FIPs to address interstate transport visibility requirements, they do not meet the requirements of prong 4 for the 2008 ozone NAAQS. 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. EPA will continue to work with Arizona to incorporate emission limits to address the requirements of the Regional Haze Rule into the Arizona SIP. For further discussion of our analysis of prong 4, please see the TSD associated with this proposal and in the docket for today's rulemaking.

IV. Proposed Action

EPA is proposing to approve Arizona's SIP as meeting the interstate transport requirements of CAA section 110(a)(2)(D)(i)(I) prongs 1 and 2 for the 2008 ozone NAAQS. EPA is proposing this approval based on the overall weight of evidence from information and analysis provided by Arizona, as well as the recent air quality modeling released in EPA's August 4, 2015 NODA, and other data analysis that confirms that emissions from Arizona will not contribute significantly to nonattainment or interfere with maintenance of the 2008 ozone NAAQS in California or any other state.

EPA is proposing to disapprove Arizona's SIP with respect to the interstate transport requirements of CAA section 110(a)(2)(D)(i)(II) prong 4 for the 2008 ozone NAAQS. Because Arizona's 2012 and 2015 submittals rely, in part, on FIPs to address interstate transport visibility requirements, they do not meet the requirements of this portion of CAA § 110(a)(2)(D) for the 2008 ozone NAAQS. 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. EPA will continue to work with Arizona to incorporate emission limits to address the requirements of the Regional Haze Rule into the Arizona SIP.

V. Statutory and Executive Order Reviews

Additional information about these statutes and Executive Orders can be found at http://www2.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review

This action is not a significant regulatory action and was therefore not submitted to the Office of Management and Budget (OMB) for review.

B. Paperwork Reduction Act (PRA)

This action does not impose an information collection burden under the PRA because this action does not impose additional requirements beyond those imposed by state law.

C. Regulatory Flexibility Act (RFA)

I certify that this action will not have a significant economic impact on a substantial number of small entities under the RFA. This action will not impose any requirements on small entities beyond those imposed by state law.

D. Unfunded Mandates Reform Act (UMRA)

This action does not contain any unfunded mandate as described in UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect small governments. This action does not impose additional requirements beyond those imposed by state law. Accordingly, no additional costs to State, local, or tribal governments, or to the private sector, will result from this action.

E. Executive Order 13132: Federalism

This action does not have federalism implications. It will not have substantial direct effects on the states, on the relationship between the national government and the states, or on the distribution of power and responsibilities among the various levels of government.

F. Executive Order 13175: Coordination With Indian Tribal Governments

This action does not have tribal implications, as specified in Executive Order 13175, because the SIP is not approved to apply on any Indian reservation land or in any other area where the EPA or an Indian tribe has demonstrated that a tribe has jurisdiction, and will not impose substantial direct costs on tribal governments or preempt tribal law. Thus, Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental Health Risks and Safety Risks

The EPA interprets Executive Order 13045 as applying only to those regulatory actions that concern environmental health or safety risks that the EPA has reason to believe may disproportionately affect children, per the definition of “covered regulatory action” in section 2-202 of the Executive Order. This action is not subject to Executive Order 13045 because it does not impose additional requirements beyond those imposed by state law.

H. Executive Order 13211: Actions That Significantly Affect Energy Supply, Distribution, or Use

This action is not subject to Executive Order 13211, because it is not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

Section 12(d) of the NTTAA directs the EPA to use voluntary consensus standards in its regulatory activities unless to do so would be inconsistent with applicable law or otherwise impractical. The EPA believes that this action is not subject to the requirements of section 12(d) of the NTTAA because application of those requirements would be inconsistent with the CAA.

J. Executive Order 12898: Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Population

The EPA lacks the discretionary authority to address environmental justice in this rulemaking.

List of Subjects in 40 CFR Part 52

• Air pollution control
• Approval and promulgation of implementation plans
• Environmental protection
• Incorporation by reference
• Oxides of nitrogen
• Ozone, and Volatile organic compounds