2014-06666. Approval and Promulgation of Implementation Plans; Idaho: Infrastructure Requirements for the 2008 Lead National Ambient Air Quality Standards

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

The Environmental Protection Agency (EPA) is proposing to approve the February 14, 2012, State Implementation Plan (SIP) submittal from Idaho demonstrating that the SIP meets the infrastructure requirements of the Clean Air Act (CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for lead (Pb) on October 15, 2008. The CAA requires that each state, after a new or revised NAAQS is promulgated, review their SIP to ensure that it meets the infrastructure requirements necessary to implement the new or revised NAAQS. The EPA is proposing to find that the Idaho SIP meets the CAA infrastructure requirements for the 2008 Pb NAAQS.

DATES:

Comments must be received on or before April 25, 2014.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R10-OAR-2012-0183, by any of the following methods:

• Email: [e-mail].
• www.regulations.gov: Follow the on-line instructions for submitting comments.
• Mail: Kristin Hall, EPA Region 10, Office of Air, Waste and Toxics (AWT-107), 1200 Sixth Avenue, Suite 900, Seattle WA, 98101.
• Hand Delivery: EPA Region 10 Mailroom, 9th floor, 1200 Sixth Avenue, Suite 900, Seattle WA, 98101. Attention: Kristin Hall, Office of Air, Waste and Toxics, AWT-107. Such deliveries are only accepted during normal hours of operation, and special arrangements should be made for deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-R10-OAR-2012-0183. The EPA's policy is that all comments received will be included in the public docket without change and may be made available online at www.regulations.gov,, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information the disclosure of which is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through www.regulations.gov or email. The www.regulations.gov Web site is an “anonymous access” system, which means the EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an email comment directly to the EPA without going through www.regulations.gov your email address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, the EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If the EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, the EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses.

Docket: All documents in the docket are listed in the www.regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or other information the disclosure of which is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy. Publicly available docket materials are available either electronically in www.regulations.gov or in hard copy during normal business hours at the Office of Air, Waste and Toxics, EPA Region 10, 1200 Sixth Avenue, Seattle WA, 98101.

FOR FURTHER INFORMATION CONTACT:

Kristin Hall at: [phone], [e-mail], or the above EPA, Region 10 address.

SUPPLEMENTARY INFORMATION:

Throughout this document wherever “we,” “us” or “our” is used, it is intended to refer to the EPA. Information is organized as follows:

Table of Contents

I. Background

II. CAA Sections 110(a)(1) and (2) Infrastructure Elements

III. EPA Approach To Review of Infrastructure SIP Submittals

IV. Analysis of the State's Submittal

V. Proposed Action

VI. Statutory and Executive Order Reviews

I. Background

On October 15, 2008, the EPA revised the level of the primary and secondary Pb NAAQS from 1.5 micrograms per cubic meter (µg/m³) to 0.15 µg/m³. The CAA requires SIPs meeting the requirements of sections 110(a)(1) and (2) be submitted by states within three years after promulgation of a new or revised standard. CAA sections 110(a)(1) and (2) require states to address basic SIP requirements, including emissions inventories, monitoring, and modeling to assure attainment and maintenance of the standards, so-called “infrastructure” requirements. States were required to submit such SIPs for the 2008 Pb NAAQS to the EPA no later than October 15, 2011.

To help states meet this statutory requirement, the EPA issued guidance to address infrastructure SIP elements under CAA sections 110(a)(1) and (2).^[1] As noted in the guidance, to the extent an existing SIP already meets the CAA section 110(a)(2) requirements, states may certify that fact via a letter to the EPA. The certification should address all requirements of the CAA section 110(a)(2) infrastructure elements as applicable for the 2008 Pb NAAQS. Such certification should include documentation demonstrating a correlation between each infrastructure element specified at 110(a)(2) and an equivalent state statutory authority in the existing or submitted SIP. As for all SIP submittals, a state should provide reasonable public notice of, and an opportunity for a public hearing on, the certification before it is submitted to the EPA.

CAA section 110(a) imposes the obligation upon states to make a SIP submission to the EPA for a new or revised NAAQS, but the contents of that submission may vary depending upon the facts and circumstances. In the case of the 2008 Pb NAAQS, states typically have met the basic program elements required in CAA section 110(a)(2) through earlier SIP submissions. On February 14, 2012, the State of Idaho made a submittal to the EPA certifying that the Idaho SIP meets the CAA section 110(a)(1) and (2) infrastructure requirements for the 2008 Pb NAAQS. The submittal included an analysis of Idaho's SIP as it relates to each section of the infrastructure requirements with regard to the 2008 Pb NAAQS. Idaho provided notice and an opportunity for public comment on the submittal from November 29, 2011 through December 28, 2011. A notice of public hearing was published in the Idaho Statesman on November 29, 2011. The State held a public hearing on December 28, 2011 in Boise, Idaho. No comments or testimony were received by the State. We have evaluated Idaho's submittal and determined that Idaho met the requirements for reasonable notice and public hearing under section 110(a)(2) of the CAA.

II. CAA Sections 110(a)(1) and (2) Infrastructure Elements

CAA section 110(a)(1) provides the procedural and timing requirements for SIP submissions after a new or revised NAAQS is promulgated. CAA section 110(a)(2) lists specific elements that states must meet for infrastructure SIP requirements related to a newly established or revised NAAQS. These requirements include SIP infrastructure elements such as modeling, monitoring, and enforcement that are designed to assure attainment and maintenance of the NAAQS. The requirements, with their corresponding CAA subsection, are listed below:

• 110(a)(2)(A): Emission limits and other control measures.
• 110(a)(2)(B): Ambient air quality monitoring/data system.
• 110(a)(2)(C): Program for enforcement of control measures.
• 110(a)(2)(D): Interstate transport.^[2]

• 110(a)(2)(E): Adequate resources.
• 110(a)(2)(F): Stationary source monitoring system.
• 110(a)(2)(G): Emergency power.
• 110(a)(2)(H): Future SIP revisions.
• 110(a)(2)(I): Areas designated nonattainment and meet the applicable requirements of part D.
• 110(a)(2)(J): Consultation with government officials; public notification; and Prevention of Significant Deterioration (PSD) and visibility protection.
• 110(a)(2)(K): Air quality modeling/data.
• 110(a)(2)(L): Permitting fees.
• 110(a)(2)(M): Consultation/participation by affected local entities.

The EPA's October 14, 2011 guidance restated our interpretation that two elements identified in CAA section 110(a)(2) are not governed by the three-year submission deadline of CAA section 110(a)(1) because SIPs incorporating necessary local nonattainment area controls are not due within three years after promulgation of a new or revised NAAQS, but rather, are due at the time the nonattainment area plan requirements are due pursuant to CAA section 172 and the various pollutant specific subparts 2-5 of part D. These requirements are: (i) submissions required by CAA section 110(a)(2)(C) to the extent that subsection refers to a permit program as required in part D, title I of the CAA, and (ii) submissions required by CAA section 110(a)(2)(I) which pertain to the nonattainment planning requirements of part D, title I of the CAA. As a result, this action does not address infrastructure elements related to CAA section 110(a)(2)(C) with respect to nonattainment new source review (NSR) or CAA section 110(a)(2)(I). Furthermore, the EPA interprets the CAA section 110(a)(2)(J) provision on visibility as not being triggered by a new NAAQS because the visibility requirements in part C, title I of the CAA are not changed by a new NAAQS.

III. EPA Approach To Review of Infrastructure SIP Submittals

The EPA is acting upon the SIP submission from Idaho that addresses the infrastructure requirements of CAA sections 110(a)(1) and 110(a)(2) for the 2008 Pb NAAQS. The requirement for states to make a SIP submission of this type arises out of CAA 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 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 the EPA's taking any action other than promulgating a new or revised NAAQS. Section 110(a)(2) includes a list of specific elements that “[e]ach such plan” submission must address.

The EPA has historically referred to these SIP submissions made for the purpose of satisfying the requirements of CAA sections 110(a)(1) and 110(a)(2) as “infrastructure SIP” submissions. Although the term “infrastructure SIP” does not appear in the CAA, the 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 the EPA rule to address the visibility protection requirements of CAA section 169A, 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.^[3] The 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, the 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 the 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 the 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.^[4] 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 the EPA to 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.^[5] This ambiguity illustrates that rather than apply all the stated requirements of section 110(a)(2) in a strict literal sense, the EPA must determine which provisions of section 110(a)(2) are applicable for a particular infrastructure SIP submission.

Another example of ambiguity within sections 110(a)(1) and 110(a)(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 the 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, the 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, the EPA can elect to act on such submissions either individually or in a larger combined action.^[6] Similarly, the 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 example, the EPA has sometimes elected to act at different times on various elements and sub-elements of the same infrastructure SIP submission.^[7]

Ambiguities within sections 110(a)(1) and 110(a)(2) may also arise with respect to infrastructure SIP submission requirements for different NAAQS. Thus, the 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, for example 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.^[8]

The EPA notes that interpretation of section 110(a)(2) is also necessary when the EPA reviews other types of SIP submissions required under the CAA. Therefore, as with infrastructure SIP submissions, the 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 that attainment plan SIP submissions required by part D have to meet the “applicable requirements” of section 110(a)(2). Thus, for example, 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 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), the 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, the 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, the 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, the 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.^[9] The EPA most recently issued guidance for infrastructure SIPs on September 13, 2013 (2013 Guidance).^[10] The EPA developed this document to provide states with up-to-date guidance for infrastructure SIPs for any new or revised NAAQS. Within this guidance, the 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. The EPA also made recommendations about many specific subsections of section 110(a)(2) that are relevant in the context of infrastructure SIP submissions.^[11] The guidance also discusses the substantively important issues that are germane to certain subsections of section 110(a)(2). Significantly, the EPA interprets sections 110(a)(1) and 110(a)(2) such that infrastructure SIP submissions need to address certain issues and need not address others. Accordingly, the 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, the EPA reviews infrastructure SIP submissions to ensure that the state's SIP appropriately addresses the requirements of section 110(a)(2)(E)(ii) and section 128. The 2013 Guidance explains the 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 multi-member 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 the EPA's evaluation of infrastructure SIP submissions because section 110(a)(2)(E)(ii) explicitly requires that the state satisfy the provisions of section 128.

As another example, the EPA's review of infrastructure SIP submissions with respect to the PSD program requirements in sections 110(a)(2)(C), (D)(i)(II), and (J) focuses upon the structural PSD program requirements contained in part C and the 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. By contrast, structural PSD program requirements do not include provisions that are not required under the 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 2012 PM_2.5 NAAQS. Accordingly, the latter optional provisions are types of provisions the EPA considers irrelevant in the context of an infrastructure SIP action.

For other section 110(a)(2) elements, however, the 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, the 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, the 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, the 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 that may be contrary to the CAA and the EPA's policies addressing such excess emissions (“SSM”); (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 the EPA; and (iii) existing provisions for PSD programs that may be inconsistent with current requirements of the EPA's “Final NSR Improvement Rule,” 67 FR 80186 (December 31, 2002), as amended by 72 FR 32526 (June 13, 2007). Thus, the EPA believes 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.^[12] It is important to note that the 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.

The EPA's approach to review of infrastructure SIP submissions is to identify the CAA requirements that are logically applicable to that submission. The EPA believes that this approach to the review of a particular infrastructure SIP submission is appropriate, because it would not be reasonable to read the general requirements of section 110(a)(1) and the list of elements in 110(a)(2) as requiring review of each and every provision of a state's existing SIP against all requirements in the CAA and the 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 the EPA evaluates adequacy of the infrastructure SIP submission. The EPA believes that a better approach is for states and the 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, the 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, the EPA believes that its approach with respect to infrastructure SIP requirements is based on a reasonable reading of sections 110(a)(1) and 110(a)(2) because the CAA provides other avenues and mechanisms to address specific substantive deficiencies in existing SIPs. These other statutory tools allow the EPA to take appropriately tailored action, depending upon the nature and severity of the alleged SIP deficiency. Section 110(k)(5) authorizes the EPA to issue a “SIP call” whenever the EPA 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.^[13] Section 110(k)(6) authorizes the EPA to correct errors in past actions, such as past approvals of SIP submissions.^[14] Significantly, the 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 the 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, the 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.^[15]

IV. Analysis of the State's Submittal

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

CAA section 110(a)(2)(A) requires SIPs to include enforceable emission limits and other control measures, means or techniques (including economic incentives such as fees, marketable permits, and auctions of emissions rights), as well as schedules and timetables for compliance, as may be necessary or appropriate to meet the applicable requirements of the CAA.

State submittal: Idaho's submittal cites an overview of the State air quality laws and regulations including portions of the Idaho Environmental Protection and Health Act (EPHA) and the Rules for the Control of Air Pollution located in the Idaho Administrative Procedures Act (IDAPA) 58.01.01. The Idaho Department of Environmental Quality (DEQ) annually updates, and submits to the EPA for incorporation by reference, all NAAQS and updates to 40 CFR part 51, Appendix W—Guidelines on Air Quality Models. Relevant laws include Idaho Code Section 39-105(3)(d) which provides Idaho DEQ with authority to supervise and administer a system to safeguard air quality, and Idaho Code Section 39-115 which provides Idaho DEQ with specific authority for the issuance of air quality permits. Specific regulations referenced in the State's submittal include IDAPA 58.01.01.107.3 (incorporation by reference of federal regulations), IDAPA 58.01.01.200-228 (permit to construct rules), IDAPA 58.01.01.400-410 (operating permit rules), IDAPA 58.01.01.600-623 (control of open burning), IDAPA 58.01.01.650-651 (control of fugitive emissions), IDAPA 58.01.01.625 (visible emissions requirements and testing), and IDAPA 58.01.01.460-461 (banking of emissions).

EPA analysis: Idaho's SIP meets the requirements of section 110(a)(2)(A) for the 2008 Pb NAAQS, subject to the following clarifications. First, this infrastructure element does not require the submittal of regulations or emission limitations developed specifically for attaining the 2008 Pb NAAQS. Furthermore, the State has no areas designated nonattainment for the 2008 Pb NAAQS and generally regulates emissions of Pb through its SIP-approved major and minor new source review (NSR) permitting programs, in addition to rules for the control of open burning, fugitive emissions, activities that generate visible emissions, and emissions banking.

The State of Idaho incorporates by reference the Federal NAAQS promulgated as of July 1, 2012, including the 2008 Pb NAAQS, at IDAPA 58.01.01.107. The EPA most recently approved IDAPA 58.01.01.107 on March 3, 2014 (79 FR 11711). This section also incorporates by reference Federal requirements for preparation, adoption, and submittal of implementation plans, Prevention of Significant Deterioration program provisions, and ambient air monitoring.

The EPA most recently approved changes to the State's major and minor NSR permitting rules on March 3, 2014 (79 FR 11711). The State's NSR rules incorporate the Federal nonattainment NSR regulations and Federal PSD regulations at IDAPA 58.01.204 and IDAPA 58.01.01.205 respectively. In addition, the State's Tier II operating permit rules at IDAPA 58.01.01.400-410 require that to obtain an operating permit, the applicant must demonstrate the source will not cause or significantly contribute to a violation of any ambient air quality standard. IDAPA 58.01.01.401.03 provides Idaho DEQ authority to require an operating permit if the department determines emission rate reductions are necessary to attain or maintain any ambient air quality standard or applicable PSD increment.

In addition to the permitting rules described above, the State has promulgated rules to limit and control emissions from open burning (IDAPA 58.01.01.600-623), fugitive dust (IDAPA 58.01.01.650-651), and activities that generate visible emissions (IDAPA 58.01.01.625). These rules include emission limits, control measures, and opacity limits. The State has also promulgated rules addressing banking of emissions at IDAPA 58.01.01.460-461. Based on the above analysis, the EPA is proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(A) for the 2008 Pb NAAQS.

We note that, in this action, we are not proposing to approve or disapprove any existing State provisions with regard to excess emissions during startup, shutdown, or malfunction (SSM) of operations at a facility. The EPA believes that a number of states may have SSM provisions that are contrary to the CAA and existing EPA guidance ^[16] and the EPA plans to address such state regulations. In the meantime, the EPA encourages any state having a deficient SSM provision to take steps to correct it as soon as possible.

In addition, we are not proposing to approve or disapprove any existing State rules with regard to director's discretion or variance provisions. The EPA believes that a number of states may have such provisions that are contrary to the CAA and existing EPA guidance (52 FR 45109), November 24, 1987, and the EPA plans to take action in the future to address such state regulations. In the meantime, we encourage any state having a director's discretion or variance provision that is contrary to the CAA and the EPA guidance to take steps to correct the deficiency as soon as possible.

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

CAA section 110(a)(2)(B) requires SIPs to include provisions to provide for establishment and operation of ambient air quality monitors, collecting and analyzing ambient air quality data, and making these data available to the EPA upon request.

State submittal: The Idaho submittal references IDAPA 58.01.01.107 and IDAPA 58.01.01.576.05 in response to this requirement. These rules incorporate by reference 40 CFR part 50, National Primary and Secondary Air Quality Standards; 40 CFR part 51, Requirements for Preparation, Adoption, and Submittal of Implementation Plans; 40 CFR part 52, Approval and Promulgation of Implementation Plans; 40 CFR part 53, Ambient Air Monitoring Reference and Equivalent Methods; and 40 CFR part 58, Appendix B Ambient Air Quality Surveillance Quality Assurance Requirements for Prevention of Significant Deterioration. The State submittal states that these rules give the State authority to implement ambient air monitoring surveillance systems in accordance with the requirements of referenced sections of the CAA. The collected information is analyzed and submitted by the State to the EPA.

EPA analysis: A comprehensive air quality monitoring plan, intended to meet the requirements of 40 CFR part 58 was submitted by Idaho on January 15, 1980 (40 CFR 52.670) and approved by the EPA on July 28, 1982. This air quality monitoring plan has been subsequently updated and approved by the EPA on March 10, 2014.^[17] This approved plan meets the EPA's revised ambient monitoring requirements for Pb promulgated on December 14, 2010 (75 FR 81126) as specified in 40 CFR part 58. Idaho provides the State's annual network monitoring plan, air quality monitoring data summaries, and a map of the State air monitoring network at: http://www.deq.idaho.gov/​air-quality/​monitoring/​monitoring-network.aspx. Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(B) for the 2008 Pb NAAQS.

110(a)(2)(C): Program for Enforcement of Control Measures

CAA section 110(a)(2)(C) requires states to include a program providing for enforcement of all SIP measures and the regulation of construction of new or modified stationary sources, including a program to meet PSD and nonattainment NSR requirements.

State submittal: The Idaho submittal refers to Idaho Code Section 39-108 which provides Idaho DEQ with authority to enforce both administratively and civilly the Idaho EPHA, or any rule, permit or order promulgated pursuant to the EPHA. Criminal enforcement is authorized at Idaho Code Section 39-109. Emergency order authority, similar to that under Section 303 of the CAA, is located at Idaho Code Section 39-112. The Idaho submittal also refers to laws and regulations requiring stationary source compliance with the NAAQS discussed in the response to CAA section 110(a)(2)(A).

The Idaho submittal also refers to the annual incorporation by reference (IBR) rulemaking which updates the Idaho SIP to include Federal changes to the NAAQS and PSD program. The submittal states that the annual IBR updates, along with IDAPA sections 200-228 (permitting requirements for new and modified sources) and 575-587 (air quality standards and area classification), provide Idaho DEQ with authority to implement the PSD and NSR program.

EPA analysis: With regards to the requirement to have a program providing for enforcement of all SIP measures, we are proposing to find that the Idaho code provisions described above provide Idaho DEQ with authority to enforce the Idaho EPHA, air quality regulations, permits, and orders promulgated pursuant to the EPHA. Idaho DEQ staffs and maintains an enforcement program to ensure compliance with SIP requirements. Idaho DEQ may issue emergency orders to reduce or discontinue emission of air contaminants where air emissions cause or contribute to imminent and substantial endangerment. Enforcement cases may be referred to the State Attorney General's Office for civil or criminal enforcement. Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(C) related to enforcement for the 2008 Pb NAAQS.

To generally meet the requirements of CAA section 110(a)(2)(C) with regards to the regulation of construction of new or modified stationary sources, a state is required to have PSD, nonattainment NSR, and minor NSR permitting programs adequate to implement the 2008 Pb NAAQS. As explained above, we are not in this action evaluating nonattainment related provisions, such as the nonattainment NSR program required by part D, Title I of the CAA. In addition, Idaho has no designated nonattainment areas for the 2008 Pb NAAQS.

We most recently approved revisions to Idaho's PSD program on March 3, 2014 (79 FR 11711), including updates of the Idaho PSD program for purposes of fine particulate matter implementation in attainment and unclassifiable areas. Previously on July 17, 2012 (77 FR 41916), we approved a revision to the Idaho SIP to provide authority to implement the PSD permitting program with respect to greenhouse gas emissions. The Idaho PSD program implements the 2008 Pb NAAQS and incorporates the Federal PSD program regulations at 40 CFR 52.21 by reference as of July 1, 2012. As a result, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(C) with regards to PSD for the 2008 Pb NAAQS.

The EPA notes that on January 4, 2013, the U.S. Court of Appeals in the District of Columbia, in Natural Resources Defense Council v. EPA, 706 F.3d 428 (D.C. Cir.), issued a judgment that remanded two of the EPA's rules implementing the 1997 PM_2.5 NAAQS, including the “Implementation of New Source Review (NSR) Program for Particulate Matter Less Than 2.5 Micrometers (PM_2.5),” (73 FR 28321, May 16, 2008) (2008 PM_2.5 NSR Implementation Rule). The court ordered the EPA to “repromulgate these rules pursuant to Subpart 4 consistent with this opinion.”Id. at 437. Subpart 4 of part D, title I of the CAA establishes additional provisions for particulate matter nonattainment areas. The 2008 PM_2.5 NSR Implementation Rule addressed by the court's decision promulgated NSR requirements for implementation of PM_2.5 in both nonattainment areas (nonattainment NSR) and attainment/unclassifiable areas (PSD). As the requirements of subpart 4 only pertain to nonattainment areas, the EPA does not consider the portions of the 2008 PM_2.5 NSR Implementation Rule that address requirements for PM_2.5 attainment and unclassifiable areas to be affected by the court's opinion. Moreover, the EPA does not anticipate the need to revise any PSD requirements promulgated in the 2008 PM_2.5 NSR Implementation Rule in order to comply with the Court's decision. Accordingly, the EPA's proposed approval of elements 110(a)(2)(C), (D)(i)(II), and (J), with respect to the PSD requirements, does not conflict with the Court's opinion. The EPA interprets the CAA section 110(a)(1) and (2) infrastructure submittals due three years after adoption or revision of a NAAQS to exclude nonattainment area requirements, including requirements associated with a nonattainment NSR program. Instead, these elements are typically referred to as nonattainment SIP or attainment plan elements, which are due by the dates statutorily prescribed under subparts 2 through 5 under part D, extending as far as ten years following designations for some elements.

In addition, on January 22, 2013, the U.S. Court of Appeals for the District of Columbia, in Sierra Club v. EPA, 703 F.3d 458 (D.C. Cir. 2013), issued a judgment that, inter alia, vacated the provisions adding the PM_2.5 Significant Monitoring Concentration to the Federal regulations, at 40 CFR 51.166(i)(5)(i)(c) and 52.21(i)(5)(i)(c), that were promulgated as part of the “Prevention of Significant Deterioration (PSD) for Particulate Matter Less than 2.5 Micrometers (PM_2.5)—Increments, Significant Impact Levels (SILs) and Significant Monitoring Concentration (SMC); Final Rule” (2010 PSD PM_2.5 Implementation Rule) (75 FR 64864). In its decision, the court held that the 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 PM_2.5 be included in all PSD permit applications. Thus, although the PM_2.5 SMC was not a required element of a state's PSD program, were a state PSD program that contains such a provision to use that provision to issue new permits without requiring ambient PM_2.5 monitoring data, such application of the vacated SMC would be inconsistent with the Court's opinion and the requirements of section 165(e)(2) of the CAA.

This decision also, on the EPA's request, vacated and remanded to the EPA for further consideration the portions of the 2010 PSD PM_2.5 Implementation Rule that revised 40 CFR 51.166 and 40 CFR 52.21 related to SILs for PM_2.5. The EPA requested this vacatur and remand of two of the three provisions in the EPA regulations that contain SILs for PM_2.5, because the wording of these two SIL provisions (40 CFR 51.166(k)(2) and 40 CFR 52.21(k)(2)) is inconsistent with the explanation of when and how SILs should be used by permitting authorities that we provided in the preamble to the Federal Register publication when we promulgated these provisions. The third SIL provision (40 CFR 51.165(b)(2)) was not vacated and remains in effect. The Court's decision does not affect the PSD increments for PM_2.5 promulgated as part of the 2010 PSD PM_2.5 Implementation Rule.

Because of the vacatur of the EPA regulations as they relate to the PM_2.5 SILs and SMC, in our previous action on March 3, 2014, we disapproved Idaho's incorporation by reference of the vacated provisions into the Idaho SIP (79 FR 11711). This action takes no additional action with respect to those SIP provisions that were previously disapproved. In this action we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(C), (D)(i)(II) and (J) as those elements relate to a comprehensive PSD program. The EPA recently amended its regulations to remove the vacated PM_2.5 SILs and SMC provisions from the PSD regulations (December 9, 2013, 78 FR 73698). The EPA will initiate a separate rulemaking in the future regarding the PM_2.5 SILs that will address the Court's remand. In the meantime, the EPA is advising states to begin preparations to remove the vacated provisions from state PSD regulations.

With regard to the minor NSR requirement of this element, we have determined that the Idaho minor NSR program adopted pursuant to section 110(a)(2)(C) of the CAA regulates emissions of Pb. Based on the foregoing, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(C) for the 2008 Pb NAAQS.

110(a)(2)(D): Interstate Transport

CAA section 110(a)(2)(D)(i) requires state SIPs to include provisions prohibiting any source or other type of emissions activity in one state from contributing significantly to nonattainment, or interfering with maintenance of the NAAQS in another state (CAA section 110(a)(2)(D)(i)(I)). Further, this section requires state SIPs to include provisions prohibiting any source or other type of emissions activity in one state from interfering with measures required to prevent significant deterioration (PSD) of air quality, or from interfering with measures required to protect visibility (i.e. measures to address regional haze) in any state (CAA section 110(a)(2)(D)(i)(II)).

State submittal: As suggested by the EPA's October 14, 2011 guidance, Idaho submitted an assessment as to whether or not emissions from Pb sources located in close proximity to the State's borders have emissions that impact neighboring states such that they contribute significantly to nonattainment or interfere with maintenance in those states. The Idaho submittal includes an inventory of Idaho Pb sources from the 2008 National Emissions Inventory, in addition to a map of the largest Pb sources. The submittal states that all Idaho Pb sources emit well below 0.5 tons per year, and that Pb sources are very dispersed and far away from the nearest designated Pb nonattainment areas. The submittal concludes that Idaho's very small Pb emission sources, combined with the distance and terrain between these sources and the closest Pb nonattainment areas, indicate that Idaho is not causing or contributing to any Pb nonattainment or maintenance issues or interfering with any control measures in applicable implementation plans in other states.

The Idaho submittal further states that East Helena, Montana, is the only designated Pb nonattainment area in states surrounding Idaho. Although in 1992 East Helena was designated nonattainment for the 1978 Pb NAAQS, the primary source of Pb emissions in East Helena was the local smelter, which shut down in 2001. In 2011, the entire state of Montana was designated unclassifiable/attainment for the 2008 Pb NAAQS, the level of which is an order of magnitude lower than the level of the 1978 NAAQS. The next closest designated Pb nonattainment area is located in Los Angeles, California. The State submittal references a South Coast Air Quality Management District Pb Monitoring Network Plan which assessed major sources of Pb emissions in Los Angeles, and found that modeled Pb concentrations dropped to low levels within 250-500 meters of the sources.

With regard to provisions prohibiting any source or other type of emissions activity in one state from interfering with measures required to prevent significant deterioration of air quality, the submittal references Idaho's SIP-approved PSD program. Finally, with regard to visibility, the Idaho submittal references the Idaho regional haze SIP submitted to the EPA on October 25, 2010, and the EPA's final Pb NAAQS Rule promulgated on November 12, 2008 that noted Pb particulate does not transport over long distances (73 FR 66964).

EPA analysis: The EPA believes, as noted in the October 14, 2011 guidance, that the physical properties of Pb prevent Pb emissions from experiencing the same travel or formation phenomena as fine particulate matter or ozone. More specifically, there is a sharp decrease in Pb concentrations, at least in the coarse fraction, as the distance from a Pb source increases. Accordingly, while it may be possible for a source in a state to emit Pb in a location and in quantities that may contribute significantly to nonattainment in, or interfere with maintenance by, any other state, the EPA anticipates that this would be a rare situation, e.g., where large sources are in close proximity to state boundaries. The EPA's experience with initial Pb designations suggests that sources that emit less than 0.5 tons per year or that are located more than two miles from a state border generally appear unlikely to contribute significantly to nonattainment in another state. The Idaho submittal indicates that the largest sources of Pb emissions in Idaho emit well below 0.5 tons per year, and are located greater than two miles from the state border. As a result, the EPA believes that the Idaho submittal provides a reasonable basis to conclude that Idaho sources of Pb emissions do not contribute significantly to nonattainment in, or interfere with maintenance of the 2008 Pb NAAQS in any other state. Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(D)(i)(I) for the 2008 Pb NAAQS.

The EPA believes that the CAA section 110(a)(2)(D)(i)(II) PSD sub-element is satisfied where new major sources and major modifications in Idaho are subject to a SIP-approved PSD program that satisfactorily implements the 2008 Pb NAAQS. We most recently approved revisions to the Idaho PSD program on March 3, 2014 (79 FR 11711), updating the program for purposes of fine particulate matter NAAQS implementation in attainment and unclassifiable areas. On July 17, 2012 (77 FR 41916), we approved a revision to the Idaho SIP to provide authority to implement the PSD permitting program with respect to greenhouse gas emissions. The Idaho PSD program implements the 2008 Pb NAAQS and incorporates the Federal PSD program regulations at 40 CFR 52.21 by reference as of July 1, 2012. We believe that our proposed approval of element 110(a)(2)(D)(i)(II) is not affected by recent court vacaturs of Federal PSD implementing regulations. Please see our discussion at section 110(a)(2)(C). Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(D)(i)(II) with regards to PSD for the 2008 Pb NAAQS.

The EPA believes, as noted in the October 14, 2011 guidance, that with regard to the CAA section 110(a)(2)(D)(i)(II) visibility sub-element, significant impacts from Pb emissions from stationary sources are expected to be limited to short distances from the source and most, if not all Pb stationary sources, are located at distances from Class I areas such that visibility impacts would be negligible. Although Pb can be a component of coarse and fine particles, Pb generally comprises a small fraction of coarse and fine particles. Furthermore, when evaluating the extent that Pb could impact visibility, Pb-related visibility impacts were found to be insignificant (e.g., less that 0.10%).^[18] Where a state's regional haze SIP has been approved as meeting all current obligations, a state may rely upon those provisions in support of its demonstration that is satisfies the requirements of CAA section 110(a)(2)(D)(i)(II) as it relates to visibility.

The Idaho submittal points to the Idaho regional haze SIP, submitted on October 25, 2010, which addresses visibility impacts across states within the region. On June 9, 2011, we approved a SIP revision which provides Idaho DEQ authority to address regional haze and to implement best available retrofit technology (BART) requirements (76 FR 33651). Subsequently on June 22, 2011, we approved portions of the Idaho regional haze SIP, including the requirements for BART (76 FR 36329). We approved the remainder of the Idaho regional haze SIP on November 8, 2012 (77 FR 66929). The EPA is proposing to find that as a result of the prior approval of the Idaho regional haze SIP, the Idaho SIP contains adequate provisions to address 110(a)(2)(D)(i)(II) visibility requirements with respect to the 2008 Pb NAAQS.

Interstate and International transport provisions: CAA section 110(a)(2)(D)(ii) requires SIPs to include provisions insuring compliance with the applicable requirements of CAA sections 126 and 115 (relating to interstate and international pollution abatement). Specifically, CAA section 126(a) requires new or modified major sources to notify neighboring states of potential impacts from the source.

State submittal: The Idaho submittal references the Idaho SIP-approved PSD program. The submittal also references IDAPA 58.01.01.209 (procedures for issuing permits) which provides notice and comment procedures for various permit actions with regard to the public and to appropriate Federal, state, international, and local agencies.

EPA analysis: We most recently approved revisions to the Idaho PSD program on March 3, 2014 (79 FR 11711), updating the program for purposes of fine particulate matter NAAQS implementation in attainment and unclassifiable areas. On July 17, 2012, the EPA approved a revision to the Idaho SIP to provide authority to implement the PSD permitting program with respect to greenhouse gas emissions (77 FR 41916). The Idaho PSD program implements the 2008 Pb NAAQS and incorporates the Federal PSD program regulations at 40 CFR 52.21 by reference as of July 1, 2012. IDAPA 58.01.01.209 (procedures for issuing permits) includes required procedures for issuing permits for new sources, including procedures for public processes, and notice to appropriate Federal, state and local agencies, consistent with the requirements of the Federal PSD program. Idaho issues notice of its draft permits and neighboring states consistently receive copies of those drafts. The State also has no pending obligations under section 115 or 126(b) of the CAA. Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(D)(ii) for the 2008 Pb NAAQS.

110(a)(2)(E): Adequate Resources

CAA section 110(a)(2)(E) requires states to provide (i) necessary assurances that the state will have adequate personnel, funding, and authority under state law to carry out the SIP (and is not prohibited by any provision of Federal or state law from carrying out the SIP or portion thereof), (ii) requires that the state comply with the requirements respecting state boards under CAA section 128 and (iii) necessary assurances that, where the state has relied on a local or regional government, agency, or instrumentality for the implementation of any SIP provision, the state has responsibility for ensuring adequate implementation of such SIP provision.

State submittal: The Idaho submittal refers to specific Idaho statutory authority including: Idaho Code 39-105, which lays out the powers and duties of Idaho DEQ's director; Idaho Code 39-106, which gives the Idaho DEQ Director authority to hire personnel to carry out duties of the department; Idaho Code 39-107, which establishes the State's Board of Environmental Quality; Idaho Code 39-107B which establishes the Department of Environmental Quality Fund to receive appropriated funds, transfers from the general fund, Federal grants, fees for services, permitting fees and other program income; and Idaho Code 39-129, which provides authority for Idaho DEQ to enter into binding agreements with local governments that are enforceable as orders.

EPA analysis: We are proposing to find that the above-referenced provisions provide Idaho DEQ with adequate authority to carry out SIP obligations with respect to the 2008 Pb NAAQS as required by CAA section 110(a)(2)(E)(i). With respect to CAA section 110(a)(2)(E)(ii), we previously approved a revision to the Idaho SIP for purposes of meeting CAA section 128 on October 24, 2013 (78 FR 63394). We are proposing to find that Idaho has provided necessary assurances that, where the State has relied on a local or regional government, agency, or instrumentality for the implementation of any SIP provision, the State has responsibility for ensuring adequate implementation of the SIP with regards to the 2008 Pb NAAQS as required by CAA section 110(a)(2)(E)(iii). Therefore we are proposing to approve the Idaho SIP as meeting the requirements of CAA sections 110(a)(2)(E) for the 2008 Pb NAAQS.

110(a)(2)(F): Stationary Source Monitoring System

CAA section 110(a)(2)(F) requires (i) the installation, maintenance, and replacement of equipment, and the implementation of other necessary steps, by owners or operators of stationary sources to monitor emissions from such sources, (ii) periodic reports on the nature and amounts of emissions and emissions-related data from such sources, and (iii) correlation of such reports by the state agency with any emission limitations or standards established pursuant to the CAA, which reports shall be available at reasonable times for public inspection.

State submittal: The Idaho submittal states that Idaho statutes and regulations provide DEQ with authority to monitor stationary source emissions for compliance purposes and make them available to the public. The submittal references the following regulatory provisions: IDAPA 58.01.01.121, which outlines the authority of Idaho DEQ to require monitoring, recordkeeping and periodic reporting related to source compliance; IDAPA 58.01.01.122, which provides Idaho DEQ authority to issue information orders and orders to conduct source emissions monitoring, record keeping, reporting and other requirements; and IDAPA 58.01.01.157, which outlines test methods and procedures for source testing and reporting to the Idaho DEQ.

EPA analysis: The provisions cited by the Idaho submittal establish compliance requirements for sources subject to major and minor source permitting to monitor emissions, keep and report records, and collect ambient air monitoring data. The provisions cited by the submittal also provide Idaho DEQ authority to issue orders to collect additional information as needed for Idaho DEQ to ascertain compliance. In addition, IDAPA 58.01.01.211 (conditions for permits to construct) and 58.01.01.405 (conditions for tier II operating permits) provide Idaho DEQ authority to establish permit conditions requiring instrumentation to monitor and record emissions data, and instrumentation for ambient monitoring to determine the effect emissions from the stationary source or facility may have, or are having, on the air quality in any area affected by the stationary source or facility. This information is made available to the public through public processes outlined at IDAPA 58.01.01.209 (procedures for issuing permits) for permits to construct and 58.01.01.404 (procedures for issuing permits) for Tier II operating permits.

Additionally, Idaho is required to submit emissions data to the EPA for purposes of the National Emissions Inventory (NEI). The NEI is the EPA's central repository for air emissions data. The EPA published the Air Emissions Reporting Rule (AERR) on December 5, 2008, which modified the requirements for collecting and reporting air emissions data (73 FR 76539). The AERR shortened the time states had to report emissions data from 17 to 12 months, giving states one calendar year to submit emissions data. All states are required to submit a comprehensive emissions inventory every three years and report emissions for certain larger sources annually through the EPA's online Emissions Inventory System. States report emissions data for the six criteria pollutants and their associated precursors—nitrogen oxides, sulfur dioxide, ammonia, lead, carbon monoxide, particulate matter, and volatile organic compounds. Many states also voluntarily report emissions of hazardous air pollutants. The EPA compiles the emissions data, supplementing it where necessary, and releases it to the general public through the Web site http://www.epa.gov/​ttn/​chief/​eiinformation.html.

Based on the analysis above, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(F) for the 2008 Pb NAAQS.

110(a)(2)(G): Emergency Episodes

CAA section 110(a)(2)(G) requires states to provide for authority to address activities causing imminent and substantial endangerment to public health, including adequate contingency plans to implement the emergency episode provisions in their SIPs.

State submittal: The Idaho submittal cites Idaho air quality laws and regulations which provide authority and rules for identifying air pollution emergency episode contingency plans and abatement strategies. Relevant sections include Idaho Code Section 39-112, which provides emergency order authority; and IDAPA 58.01.01.550-561, the air pollution emergency rules section in the Idaho SIP.

EPA analysis: As noted in the October 14, 2011 guidance, based on the EPA's experience to date with the Pb NAAQS and designating Pb nonattainment areas, the EPA expects that an emergency episode associated with Pb emissions would be unlikely and, if it were to occur, would be the result of a malfunction or other emergency situation at a relatively large source of Pb. Accordingly, the EPA believes that the central components of a contingency plan would be to reduce emissions from the source at issue and public communication as needed. We note that 40 CFR part 51, subpart H (51.150-51.152) and 40 CFR part 51, Appendix L do not apply to Pb.0

Section 303 of the CAA provides authority to the EPA Administrator to restrain any source from causing or contribution to emissions which present an “imminent and substantial endangerment to public health or welfare, or the environment.” We find that Idaho Code Section 112 provides the Idaho DEQ Director with comparable authority.

The Idaho air pollution emergency rules at IDAPA 58.01.01.550-561 were previously approved by the EPA on January 16, 2003 (68 FR 2217). In addition, the EPA approved IDAPA 58.01.01.562 (specific emergency episode abatement plans for point sources) on January 16, 2003 (68 FR 2217). This provision requires that specific point sources adopt and implement their own emergency episode abatement plans in accordance with the criteria set forth in IDAPA 58.01.01.551 through 556. Accordingly, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(G) for the 2008 Pb NAAQS.

110(a)(2)(H): Future SIP Revisions

CAA section 110(a)(2)(H) requires that SIPs provide for revision of such plan (i) from time to time as may be necessary to take account of revisions of such national primary or secondary ambient air quality standard or the availability of improved or more expeditious methods of attaining such standard, and (ii), except as provided in paragraph 110(a)(3)(C), whenever the Administrator finds on the basis of information available to the Administrator that the SIP is substantially inadequate to attain the NAAQS which it implements or to otherwise comply with any additional requirements under the CAA.

State submittal: The Idaho submittal refers to Idaho Code Section 39-105(2) and (3)(d) which provides Idaho DEQ with authority to revise rules, in accordance with Idaho administrative procedures for rulemaking, to meet national ambient air quality standards as incorporated by reference in IDAPA 58.01.01.107. The submittal also refers to provisions at IDAPA 58.01.01.575-.587, which include area classifications, designations, PSD classifications, and references to the State's incorporation by reference of the Federal NAAQS and Federal PSD increments.

EPA analysis: We find that Idaho has adequate authority to regularly update the SIP to take into account revisions of the NAAQS and other related regulatory changes. In practice, the State regularly submits SIP revisions to the EPA to revise the SIP for recent Federal regulatory changes. We most recently approved revisions to the Idaho SIP on March 3, 2014 (79 FR 11711), April 3, 2013 (78 FR 20001), and March 19, 2013 (78 FR 16790). Accordingly, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(H) for the 2008 Pb NAAQS.

110(a)(2)(I): Nonattainment Area Plan Revision Under Part D

There are two elements identified in CAA section 110(a)(2) not governed by the three-year submission deadline of CAA section 110(a)(1) because SIPs incorporating necessary local nonattainment area controls are not due within three years after promulgation of a new or revised NAAQS, but are rather due at the time of the nonattainment area plan requirements pursuant to section 172 and the various pollutant specific subparts 2-5 of part D. These requirements are: (i) Submissions required by CAA section 110(a)(2)(C) to the extent that subsection refers to a permit program as required in part D, title I of the CAA, and (ii) submissions required by section 110(a)(2)(I) which pertain to the nonattainment planning requirements of part D, title I of the CAA. As a result, this action does not address infrastructure elements related to CAA section 110(a)(2)(C) with respect to nonattainment NSR or CAA section 110(a)(2)(I).

110(a)(2)(J): Consultation With Government Officials

CAA section 110(a)(2)(J) requires states to provide a process for consultation with local governments and Federal Land Managers carrying out NAAQS implementation requirements pursuant to CAA section 121. CAA section 110(a)(2)(J) further requires states to notify the public if NAAQS are exceeded in an area and to enhance public awareness of measures that can be taken to prevent exceedances. Lastly, CAA section 110(a)(2)(J) requires states to meet applicable requirements of Part C, title I of the CAA related to prevention of significant deterioration and visibility protection.

State submittal: The Idaho submittal refers to laws and regulations relating to authority to carry out the PSD part C requirements and the consultation process and notification to the public, the EPA and Federal Land Managers. Specific provisions referenced include IDAPA 58.01.01.209, 364, and 404 which provide for public processes for SIPs and permitting under IDAPA 58.01.01.200-223 (permit to construct rules); Idaho Code 39-129 which provides Idaho DEQ authority to enter into agreements with local governments; Idaho Code 39-105.03(c) which promotes outreach with local governments; IDAPA 58.01.01.563-574 (transportation conformity); IDAPA 58.01.23.800-860 (rulemaking); and IDAPA 58.01.01.667 (regional haze). In addition, the Idaho submittal states that Idaho DEQ submits information to the EPA's AIRNOW program and provides daily air quality index scores for locations throughout the state on the Web site at http://www.deq.idaho.gov/​air/​aqindex.cfm.

EPA analysis: The Idaho SIP includes specific provisions for consulting with local governments and Federal Land Managers as specified in CAA section 121, including the Idaho rules for major source PSD permitting. The EPA most recently approved Idaho permitting rules at IDAPA 58.01.01.209 and 58.01.01.404, which provide opportunity and procedures for public comment and notice to appropriate Federal, state and local agencies, on November 26, 2010 (75 FR 47530) and January 16, 2003 (68 FR 2217) respectively. We most recently approved the Idaho rules that define transportation conformity consultation on April 12, 2001 (66 FR 18873). While transportation conformity requirements do not apply for Pb because of the nature of the standard, the consultation procedures that Idaho has in place to implement transportation conformity requirements provides evidence of the State's ability to consult with other governmental agencies on air quality issues.

In practice, Idaho DEQ routinely coordinates with local governments, states, Federal Land Managers and other stakeholders on air quality issues including permitting action, transportation conformity, and regional haze. Therefore, we are proposing to find that the Idaho SIP meets the requirements of CAA section 110(a)(2)(J) for consultation with government officials for the 2008 Pb NAAQS.

Section 110(a)(2)(J) also requires the public be notified if NAAQS are exceeded in an area and to enhance public awareness of measures that can be taken to prevent exceedances. The EPA calculates an air quality index for five major air pollutants regulated by the CAA: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. This air quality index provides daily information to the public on air quality. While Pb is not specifically part of the air quality index, we note that Idaho actively participates and submits information to the EPA's AIRNOW and Enviroflash Air Quality Alert programs which provide information to the public on the air quality in their locale. In addition, Idaho provides air quality reports and forecasts to the public on the Idaho DEQ Web site at http://www.deq.idaho.gov/​air-quality/​monitoring/​daily-reports-and-forecasts.aspx,, as well as measures that can be taken to prevent exceedances.

Idaho provides the State's annual network monitoring plan, annual air quality monitoring data summaries, and a map of the state air monitoring network to the public on their Web site at http://www.deq.idaho.gov/​air-quality/​monitoring/​monitoring-network.aspx. The monitoring plans and data summaries include information on Pb monitoring. In addition, the Idaho SIP provides authority at IDAPA 58.01.01.557 through 560 for notifying the public when air quality is degrading, as determined by the Director of Idaho DEQ, and that the Director will utilize appropriate news media to insure that information is announced to the public about the definition of the extent of the problem, the action taken by the Director, the air pollution forecast for the next few days, notice of when the next statement from DEQ will be issued, a listing of all general procedures which the public, commercial, institution and industrial sectors are required to follow, and specific warnings and advice to those persons who because of acute or chronic health problems may be most susceptible. Therefore, we are proposing to find that the Idaho SIP meets the requirements of CAA section 110(a)(2)(J) for public notification for the 2008 Pb NAAQS.

Turning to the requirement in CAA section 110(a)(2)(J) that the SIP meet the applicable requirements of part C of title I of the CAA, we have evaluated this requirement in the context of CAA section 110(a)(2)(C) with respect to permitting. The EPA most recently approved revisions to Idaho's PSD program on March 3, 2014 (79 FR 11711), updating the program for purposes of fine particulate matter NAAQS implementation in attainment and unclassifiable areas. On July 17, 2012 (77 FR 41916), we approved a revision to the Idaho SIP to provide authority to implement the PSD permitting program with respect to greenhouse gas emissions. The State's PSD program implements the 2008 Pb NAAQS and incorporates the Federal PSD program regulations at 40 CFR 52.21 by reference as of July 1, 2012. We believe that our proposed approval of element 110(a)(2)(J) is not affected by recent court vacaturs of Federal PSD implementing regulations. Please see our discussion at section 110(a)(2)(C). Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA 110(a)(2)(J) with regards to PSD for the 2008 Pb NAAQS.

With regard to the applicable requirements for visibility protection, the EPA recognizes that states are subject to visibility and regional haze program requirements under part C of the CAA. In the event of the establishment of a new NAAQS, however, the visibility and regional haze program requirements under part C do not change. Thus we find that there is no new applicable requirement relating to visibility triggered under CAA section 110(a)(2)(J) when a new NAAQS becomes effective.

Based on the above analysis, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(J) for the 2008 Pb NAAQS.

110(a)(2)(K): Air Quality and Modeling/Data

CAA section 110(a)(2)(K) requires that SIPs provide for (i) the performance of such air quality modeling as the Administrator may prescribe for the purpose of predicting the effect on ambient air quality of any emissions of any air pollutant for which the Administrator has established a national ambient air quality standard, and (ii) the submission, upon request, of data related to such air quality modeling to the Administrator.

State submittal: The Idaho submittal states that air quality modeling is conducted during development of revisions to the SIP, as appropriate for the State to demonstrate attainment with required air quality standards. Modeling is also addressed in the permitting process (see discussion at CAA section 110(a)(2)(A) above). Estimates of ambient concentrations are based on air quality models, data bases and other requirements specified in 40 CFR part 51, Appendix W (Guidelines on Air Quality Models) and incorporated by reference at IDAPA 58.01.01.107.

EPA analysis: The EPA most recently approved IDAPA 58.01.01.107, which incorporates by reference the following EPA regulations: Requirements for Preparation, Adoption, and Submittal of Implementation Plans, 40 CFR part 51; National Primary and Secondary Ambient Air Quality Standards, 40 CFR part 50; Approval and Promulgation of Implementation Plans, 40 CFR part 52; Ambient Air Monitoring Reference and Equivalent Methods, 40 CFR part 53; and Ambient Air Quality Surveillance, 40 CFR part 58 revised as of July 1, 2012, on March 3, 2014 (79 FR 11711). Idaho has incorporated by reference the 2008 Pb NAAQS into State regulations. While Idaho has no nonattainment areas for the 2008 Pb NAAQS, the State has submitted modeling data to EPA related to other pollutants. For example, Idaho submitted to the EPA the PM₁₀ Maintenance Plan for Northern Ada County/Boise Idaho Area which contained air quality modeling data. We approved the maintenance plan as a SIP revision on October 27, 2003 (68 FR 61106). Therefore, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(K) for the 2008 Pb NAAQS.

110(a)(2)(L): Permitting Fees

CAA section 110(a)(2)(L) requires SIPs to require each major stationary source to pay permitting fees to cover the cost of reviewing, approving, implementing and enforcing a permit.

State submittal: The State submittal references the regulatory requirements for annual registration of title V sources through the Idaho Tier I permitting program and the annual assessment and payment of fees to support the Tier I permitting program.

EPA analysis: The EPA approved the Idaho title V program on October 4, 2001 (66 FR 50574) with an effective date of November 5, 2001. While the State's operating permit program is not formally approved into the State SIP, it is a legal mechanism the state can use to ensure that Idaho DEQ has sufficient resources to support the air program, consistent with the requirements of the SIP. Before the EPA can grant full approval, a state must demonstrate the ability to collect adequate fees. The Idaho title V program included a demonstration that fees were adequate, and the State will collect a fee from title V sources above the presumptive minimum in accordance with 40 CFR 70.9(b)(2)(i). In addition, Idaho regulations require fees for purposes of major and minor NSR permitting, as specified in IDAPA 58.01.01.224 through 227. Therefore, we are proposing to conclude that Idaho has satisfied the requirements of CAA section 110(a)(2)(L) for the 2008 Pb NAAQS.

110(a)(2)(M): Consultation/Participation by Affected Local Entities

CAA section 110(a)(2)(M) requires states to provide for consultation and participation in SIP development by local political subdivisions affected by the SIP.

State submittal: The Idaho submittal states that Idaho DEQ follows the consultation and participation process outlined in 40 CFR 51.102 and incorporates 40 CFR part 51 by reference at IDAPA 58.01.01.107. The submittal also references the following regulations: IDAPA 58.01.01.209, which provides for public comment and notice related to proposed actions on permit applications to construct; IDAPA 58.01.01.404, which provides for public comment and notice on actions related to Tier II operating permits; and IDAPA 58.01.01.563-574, which provides for transportation conformity consultation process and procedures.

EPA analysis: We most recently approved IDAPA 58.01.01.107, which incorporates by reference EPA regulations at 40 CFR part 51—Requirements for Preparation, Adoption, and Submittal of Implementation Plans on March 3, 2014 (79 FR 11711). In addition, we most recently approved Idaho permitting rules at IDAPA 58.01.01.209 and 58.01.01.404 which provide opportunity and procedures for public comment and notice to appropriate Federal, state and local agencies on November 26, 2010 (75 FR 47530) and January 16, 2003 (68 FR 2217) respectively. Finally, we approved the State rules that define transportation conformity consultation on April 12, 2001 (66 FR 18873). While transportation conformity requirements do not apply for Pb because of the nature of the standard, the consultation procedures that Idaho has in place to implement transportation conformity requirements provides evidence of the State's ability to consult with other governmental agencies on air quality issues.

Based on the analysis above, we are proposing to approve the Idaho SIP as meeting the requirements of CAA section 110(a)(2)(M) for the 2008 Pb NAAQS.

V. Proposed Action

The EPA is proposing to approve the February 14, 2012, submittal from the State of Idaho to demonstrate that the SIP meets the requirements of sections 110(a)(1) and (2) of the CAA for the Pb NAAQS promulgated on October 15, 2008. Specifically, we are proposing to find that the Idaho SIP meets the following CAA section 110(a)(2) infrastructure elements for the 2008 Pb NAAQS: (A), (B), (C), (D), (E), (F), (G), (H), (J), (K), (L), and (M).

VI. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this proposed action merely approves the state's law as meeting Federal requirements and does not impose additional requirements beyond those imposed by the state's law. For that reason, this proposed action:

• Is not a “significant regulatory action” subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);
• does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
• does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
• is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
• is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);
• is not subject to the requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because this action does not involve technical standards; and
• does not provide the EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, this rule does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP is not approved to apply in Indian country located in the State, and the EPA notes that it will not impose substantial direct costs on tribal governments or preempt tribal law.

List of Subjects in 40 CFR Part 52

• Environmental protection
• Air pollution control
• Incorporation by reference
• Intergovernmental relations
• Lead
• Particulate matter, and Reporting and recordkeeping requirements

Authority: 42 U.S.C. 7401 et seq.

Dated: March 13, 2014.

Dennis J. McLerran,

Regional Administrator, Region 10.

Footnotes

1.  Stephen D. Page, Director, Office of Air Quality Planning and Standards. “Guidance on Infrastructure State Implementation Plan (SIP) Elements Required Under Sections 110(a)(1) and (2) for the 2008 Lead (Pb) National Ambient Air Quality Standards.” Memorandum to EPA Air Division Directors, Regions I-X, October 14, 2011.

2.  In accordance with the D.C. Circuit decision in EME Homer City, the EPA at this time is not treating the 110(a)(2)(D)(i)(I) SIP submission from Idaho for the 2008 Pb NAAQS as a required SIP submission. See EME Homer City Generation, L.P. v. EPA, 696 F .3d 7 (D.C. Cir. 2012), cert. granted, 2013 U.S. Lexis 4801 (2013). However, even if the submission is not considered to be “required,” the EPA must act on the 110(a)(2)(D)(i)(I) SIP submission from Idaho because section 110(k)(2) of the CAA requires the EPA to act on all SIP submissions. Unless the EME Homer City decision is reversed or otherwise modified by the Supreme Court, which granted review of the case on June 24, 2013, states are not required to submit 110(a)(2)(D)(i)(I) SIPs until the EPA has quantified their obligations under that section. The portions of the SIP submission relating to 110(a)(2)(D)(i)(II) and 110(a)(2)(D)(ii), in contrast, are required. In this notice, we are proposing to act on all portions of Idaho's 110(a)(2)(D) submission.

3.  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 SIP-approved 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.

4.  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 NO_X 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)).

5.  The 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.

6.  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) (the EPA's final action approving the structural PSD elements of the New Mexico SIP submitted by the State separately to meet the requirements of the EPA's 2008 PM_2.5 NSR rule), and “Approval and Promulgation of Air Quality Implementation Plans; New Mexico; Infrastructure and Interstate Transport Requirements for the 2006 PM_2.5 NAAQS,” (78 FR 4337) (January 22, 2013) (the EPA's final action on the infrastructure SIP for the 2006 PM_2.5 NAAQS).

7.  On December 14, 2007, the State of Tennessee, through the Tennessee Department of Environment and Conservation, made a SIP revision to the EPA demonstrating that the State meets the requirements of sections 110(a)(1) and (2). The 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), the EPA took separate proposed and final actions on all other section 110(a)(2) infrastructure SIP elements of Tennessee's December 14, 2007 submittal.

8.  For example, implementation of the 1997 PM_2.5 NAAQS required the deployment of a system of new monitors to measure ambient levels of that new indicator species for the new NAAQS.

9.  The EPA notes, however, that nothing in the CAA requires the 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 the EPA provides guidance or regulations pertaining to such submissions. EPA elects to issue such guidance in order to assist states, as appropriate.

10.  “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.

11.  The 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). The 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.3d7 (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, the 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 the EPA elects to provide guidance on a particular section has no impact on a state's CAA obligations.

12.  By contrast, the 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 for excess emissions during SSM events, then the 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.

13.  For example, the 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).

14.  The 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). The EPA has previously used its authority under CAA section 110(k)(6) 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).

15.  See, e.g., the 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 (Jan. 26, 2011) (final disapproval of such provisions).

16.  For further description of the EPA's SSM Policy, see, e.g., a memorandum dated September 20, 1999, titled “State Implementation Plans: Policy Regarding Excess Emissions During Malfunctions, Startup, and Shutdown,” from Steven A. Herman, Assistant Administrator for Enforcement and Compliance Assurance, and Robert Perciasepe, Assistant Administrator for Air and Radiation. Also, the EPA issued a proposed action on February 12, 2013, titled “State Implementation Plans: Response to Petition for Rulemaking: Findings of Substantial Inadequacy; and SIP Calls to Amend Provisions Applying to excess Emissions During Periods of Startup, Shutdown and Malfunction.” This rulemaking responds to a petition for rulemaking filed by the Sierra Club that concerns SSM provisions in 39 states' SIPs (February 22, 2013, 78 FR 12460).

17.  Idaho Air Monitoring Network Plan Approval Letter, dated March 10, 2014.

18.  Analysis by Mark Schmidt, OAQPS. “Ambient Pb's Contribution to Class 1 Area Visibility Impairment,” November 7, 2011.